- Oct 2024
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www.coastal.edu www.coastal.edu
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HazingHazing is any reckless or intentional act, occurring on or off campus, that produces physical, mental, or emotionalpain; discomfort; humiliation; embarrassment; or ridicule directed toward other students or groups (regardless oftheir willingness to participate), that is required or expected of new or current members and which is not related
after learning about all of the horrible effects of hazing I am glad it is talked about in the code of conduct
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If the student believes that due process has failed or that substantive issues related to the case were notreviewed at the CAIC hearing, the student may submit a written appeal to the dean of the college in whichthe course under consideration was offered
If the student disagrees with the allegation, they can submit an appeal that can be reviewed
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viewer.athenadocs.nl viewer.athenadocs.nl
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Power distance:
cultures with high power distance tend to have hierarchical structures and clear authority roles, while low power distance cultures value equality and open dialogue
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viewer.athenadocs.nl viewer.athenadocs.nl
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Sternberg identifies three main forms of intelligence: analytical, creative and practical intelligence.
Sternberg's 3 vormige intelligentie: - Analytisch. - Creatief. - Praktisch.
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This general intelligence factor forms the basis for various mental skills, such as verbal reasoning, quantitative reasoning, abstract visual reasoning and short-term memory.
Algemene intelligentiefactor (=G); - Verbaal redeneren. - Kwantitatief redeneren. - Abstract visueel redeneren. - Kortetermijngeheugen.
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Flynn Effect
Flynn Effect=omgevingsfactoren die IQ verhogen over generaties heen.
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Bell Curve
Bell Curve=genetische factoren.
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However, this is a big over generalization
Redenen van culturele verschillen in cognitie:<br /> - Situationele factoren/ experimentele onderzoeksontwerpen. - Attributiebiases zijn universeler dan gedacht. - Analytische waarnemingen werden niet gekoppeld aan interne locus of contral/ holistische waarnemingen werden niet gekoppeld aan externe locus of control. - Sommige geheugendelen zijn universeler. - Trainingseffecten worden niet in overweging genomen.
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This implies that Western cultures look more to paper, pictures and flat screens, or 2D shapes, so they may be more accustomed to recognizing such pictures as a Muller-Lyer illusion.
3 dimensies symboliseren in 2: westerse culturen zien vaker in 2d; meer gewend aan afbeeldingen zoals bij deze illusies.
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social-media-ethics-automation.github.io social-media-ethics-automation.github.io
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In 2016, when Donald Trump was running a campaign to be the US President, one twitter user pointed out that you could see which of the Tweets on Donald Trump’s Twitter account were posted from an Android phone and which from an iPhone, and that the tone was very different. A data scientist decided to look into it more and found: “My analysis … concludes that the Android and iPhone tweets are clearly from different people, “posting during different times of day and using hashtags, links, and retweets in distinct ways, “What’s more, we can see that the Android tweets are angrier and more negative, while the iPhone tweets tend to be benign announcements and pictures. …. this lets us tell the difference between the campaign’s tweets (iPhone) and Trump’s own (Android).” (Read more in this article from The Guardian) Note: we can no longer run code to check this ourselves because first, Donald Trump’s account was suspended in January 2021 for inciting violence, then when Elon Musk decided to reinstate Donald Trump’s account (using a Twitter poll as an excuse, but how many of the votes were bots?), Elon Musk also decided to remove the ability to look up a tweet’s source.
I believe that the contrast between the 2 different types of tweets, the ones made on Android and Apple truly highlight how the tone and the message can really differ depending on who is managing the account. This difference also shows how data analysis can play a role in finding patterns in tweets and forms of communication. It also can highlight the difference between personal and campaign driven tweets and posts.
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using a Twitter poll as an excuse, but how many of the votes were bots?
I thought this was interesting just because of all the misinformation that led Trumps twitter to get banned in the first place, bots could've been the reason for reinstating him. it's just an interesting thought of how so much cannot be trusted from the internet. Even previously stated, with the Android and iPhone, it's hard to tell what's true and what's not.
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social-media-ethics-automation.github.io social-media-ethics-automation.github.io
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Inauthentic behavior is when the reality doesn’t match what is being presented. Inauthenticity has, of course, existed throughout human history, from Ea-nasir complaining in 1750 BCE that the copper he ordered was not the high quality he had been promised, to 1917 CE in England when Arthur Conan Doyle (the author of the Sherlock Holmes stories) was fooled by photographs that appeared to be of a child next to fairies
I feel like this issue is magnified in today's information environment. People portray themselves online, which often leads to a disconnect that can damage relationships and self-perception. We need more authentic interactions and more honesty between people.
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Schrodinger’s asshole: the guy who says awful shit, and decides if he was “only kidding” depending on your reaction.
I have had a Schrodinger's asshole account harass me as an Asian individual during Covid one time and he pulled this move after I took matters into my own hands. I don't see too many of these types of accounts anymore, but there were a lot of them back in 2020.
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Astroturfing: An artificially created crowd to make something look like it has popular support
This reminds me of Kpop fans who buy robots to like their idols' posts in order to make their idols look more popular. Because people have a herd mentality, when people find that an idol's post has a lot of likes, they may choose to like it as well.
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social-media-ethics-automation.github.io social-media-ethics-automation.github.io
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he way we present ourselves to others around us (our behavior, social role, etc.) is called our public persona. We also may change how we behave and speak depending on the situation or who we are around, which is called code-switching. While modified behaviors to present a persona or code switch may at first look inauthentic, they can be a way of authentically expressing ourselves in each particular setting. For example: Speaking in a formal manner when giving a presentation or answering questions in a courtroom may be a way of authentically sharing your experiences and emotions, but tailored to the setting Sharing those same experiences and emotions with a close friend may look very different, but still can be authentic Different communities have different expectations and meanings around behavior and presentation. So what is appropriate authentic behavior depends on what group you are from and what group you are interacting with, like this gif of President Obama below:
I believe that code-switching and our public personas allow us to navigate different social contexts and situations that we may be put in while also still being able to express authentic versions of ourselves. Adjusting our behavior to match different social situations reflects our understanding of social expectations and our ability to communicate in different ways.
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On social media, context collapse is a common concern, since on a social networking site you might be connected to very different people (family, different groups of friends, co-workers, etc.). Additionally, something that was shared within one context (like a private message), might get reposted in another context (publicly posted elsewhere).
the paragraph introduces an important and complex issue concisely. Adding a few more details about its effects on behavior, specific examples, and emotional impact could make it even more insightful.
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social-media-ethics-automation.github.io social-media-ethics-automation.github.io
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Parasocial relationships are when a viewer or follower of a public figure (that is, a celebrity) feel like they know the public figure, and may even feel a sort of friendship with them, but the public figure doesn’t know the viewer at all.
This happens so often even with creators that don't have a big following, and I personally find this quite concerning. There are even individuals going as far as getting cosmetic surgery to look like a person or even finding their address.
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Another phenomenon related to authenticity which is common on social media is the parasocial relationship. Parasocial relationships are when a viewer or follower of a public figure (that is, a celebrity) feel like they know the public figure, and may even feel a sort of friendship with them, but the public figure doesn’t know the viewer at all. Parasocial relationships are not a new phenomenon, but social media has increased our ability to form both sides of these bonds. As comedian Bo Burnham put it: “This awful D-list celebrity pressure I had experienced onstage has now been democratized.”
The explanation of parasocial relationships impressed me the first time since it could explain why viewers feel like they "know" the public figure. Also, I feel surprised about that parasocial relationships appears from intimate-seeming interactions over time, often via media that simulate personal engagement. But in my perspective, this interactivity blurs the line between public and personal.
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What are the ways in which a parasocial relationship can be authentic or inauthentic?
I suppose the different between authentic or inauthentic parasocial relationship in streamers-followers sense is whether the celebrity consider a specific follower as "fans". However, this judgement often based on whether followers spend enough money on streamers and streamers don't their fans' names (even username) in most circumstance. Therefore, I don't see any difference for follower between authentic and inauthentic parasocial relationship.
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Where do you see parasocial relationships on social media?
The relationship between streamers and their followers has became the one of the most common parasocial relationship, nowadays. In some sense, this kind of parasocial relationship was built by streamers on purpose. They will pick nicknames for their followers' group and responds to chat like they are talking like friends.
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shange-fall24.dhcbarnard.org shange-fall24.dhcbarnard.org
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visual artist
ok
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Ridin' the Moon
here
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thank
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in contact
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Michael Denneny
Mr. Denneny's archive is now at Brown University
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rsginc.github.io rsginc.github.io
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left_join(tbi$hh) %>%
As written it will return NA for entire sample_segment column. Instead put left_join(tbi$hh, by = c("survey_year", "hh_id")) %>%
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left_join(tbi$hh, by = "hh_id") %>%
If you join it like this, survey_year will become survey_year.x. Instead do left_join(tbi$hh, by = c("hh_id", "survey_year")) %>%
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left_join(tbi$hh, by = "hh_id") %>%
If you join it like this, survey_year will become survey_year.x. Instead do left_join(tbi$hh, by = c("hh_id", "survey_year")) %>%
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left_join(tbi$hh, by = "hh_id") %>%
If you join it like this, survey_year will become survey_year.x. Instead do left_join(tbi$hh, by = c("hh_id", "survey_year")) %>%
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mode_type = value_labels_upcoded[variable == "mode_type", value],
mode_type = values_list[variable_unified == "mode_type", value_upcoded],
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shange-fall24.dhcbarnard.org shange-fall24.dhcbarnard.org
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Word Paintings
i like the phrase
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www.biorxiv.org www.biorxiv.org
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Author response:
The following is the authors’ response to the original reviews.
Reviewer #1 (Recommendations For The Authors):
Figures 1 and 2. How do the authors know that the lysine mutations are specific to constitutive activity and not because it is causing the channel to be now voltage sensitive?
As shown in the revised Figs. 1b, S2a, and 3b, TMEM16F I521K/M522K, TMEM16F I521E, and TMEM16A I546K/I547K spontaneously expose PS, respectively. Neither membrane depolarization nor calcium stimulation was introduced under these conditions and the cells were grown in calcium-free media after transfection to limit calcium-dependent activation. Our new experiments further demonstrate that TMEM16F T526K (Fig. 1b) and TMEM16A E551K (Fig. 3b), which are further away from the activation gate, exhibit either strongly attenuated or lack spontaneous lipid scrambling activity. According to these results, the gain-of-function mutants (TMEM16F
I521K/M522K/I521E and TMEM16A I546K/I547K) are indeed constitutively active. This constitutive scramblase activity is not due to a gain of voltage sensitivity as ion channel activity is also minimal around the resting membrane potential of a HEK cell (Fig. 1d, e and Fig. 3d, e).
The authors see very large currents of 5 -10 nA in their electrophysiology experiments in Figures 2D and 3D. I understand that Figure 2D are whole-cell recordings but are the authors confident that the currents that they are recordings from the mutants are indeed specific to TMEM16A. More importantly, in Figure 3D they see 3-5nA currents in insideout patches, which is huge. They have no added divalent in their bath solution, which could lead to larger single-channel amplitudes, but 3-5nA seems excessive. Some control to demonstrate that these are indeed OSCA1.2 currents is important.
TMEM16A and TMEM16F are well-known for their high cell surface expression. Therefore, the current amplitude is usually huge even in excised inside-out or outside-out patches—please see our previous publications for details: 1) 10.1016/j.cell.2012.07.036, 2) 10.7554/eLife.02772, 3) 10.1038/s41467-019-11784-8, 4) 10.1038/s41467-019-09778-7, 5) 10.1016/j.celrep.2020.108570, 6) 10.1085/jgp.202012704, and 7) 10.1085/jgp.202313460.
HEK293 cells do not have endogenous TMEM16A (https://doi.org/10.1038/nature07313, 10.1016/j.cell.2008.09.003 , DOI: 10.1126/science.1163518). It therefore serves as a widely used cell line for studying TMEM16A biophysics. As overexpressing the WT control barely elicited any obvious current in 0 Ca2+ (Fig. 3d), there is no doubt that the large outward-rectifying current (hallmark of CaCC) in the revised Fig. 3d (previous Fig. 2D) was elicited from the mutant TMEM16A channels. The strong outward rectification also rules out the possibility of this being leak current.
Regarding Fig. 4d (previous Fig. 3D), OSCA1.2 has excellent surface expression as shown in Fig. 4b. OSCA1.2 also has much higher single channel conductance (121.8 ± 3.4 pS, 10.7554/eLife.41844) than TMEM16A (~3-8 pS) and TMEM16F (<1 pS). Therefore, recording nA OSCA1.2 current from excised patches is normal given larger OSCA1.2 current at depolarized voltages than the current recorded at hyperpolarized voltages (please see our explanation in the next response). As the reviewer pointed out, lack of divalent ions in our experimental conditions may also partially contribute to the large conductance. To further verify, we conducted mock transfection recordings (please see Author response image 1 below). WT- but not mock (GFP)transfected cells gave rise to large current, further supporting that the recorded current was indeed through OSCA1.2.
Author response image 1.
Representative inside-out currents for mock (GFP)- and OSCA1.2 WT-transfected cells. OSCA1.2 is responsible for nA currents elicited by the pressure and voltage protocols shown.
Figure 3D and 5D. Most of the traces and current quantification is done at positive potentials and is outward current. Do the authors observe inward currents? It is difficult to judge by the figures since currents are so large. OSCA/TMEM63s are cationic channels and all published data on these channels have demonstrated robust inward currents at negative, physiologically relevant potentials. The lack of inward currents but only large outward currents suggests that these mutations could be doing something else to the channel.
Yes. We indeed observe inward current at negative holding potentials under pressure clamp (Author response image 2). However, mechanosensitive OSCA and TMEM63A channels are also voltage dependent. Their outward current is an order of magnitude larger at depolarized voltages (e.g., Author response image 2, also 10.7554/eLife.41844, see Fig. 1H).
Author response image 2.
Voltage-dependent rectification of OSCA1.2 current. a. Representative OSCA1.2 trace (bottom) elicited by a voltage-ramp under -50 mmHg (top). b. The difference in inward and outward current amplitudes.
We found that quantifying the OSCA1.2 outward current has advantages over the inward current. Usually, using the gold standard pressure clamp protocol at negative holding voltages, peak inward current amplitude is quantified. However, OSCA inward current quickly inactivates (10.7554/eLife.41844, see Fig. 1C). This makes robust quantification and comparison with mutant channels difficult. Holding the membrane at a constant pressure and measuring OSCA1.2 G-V overcomes these issues associated with the classical inward current measurements. The large depolarization-driven outward current does not inactivate, and robust tail current (Response Fig. 1, 2) allows us to construct G-V relationships. We found quantifying mutants’ voltage dependence at constant pressure is more consistent than quantifying pressure dependence at constant voltage. These advantages make our new protocol preferable to the commonly used gold standard pressure clamp protocol for characterizing and comparing the gating mutations identified in this manuscript.
Figure 3 and 5. Why are mechanically activated currents being recorded at random pressure stimuli (-50 mmHg for OSCA) and (-80 mmHg for Tmem63a)? The gold standard in the field is to run an entire pressure response curve. Given that only outward currents are observed at membrane potentials +120mV and above at 0mmHg, this questions whether they are indeed constitutively active.
As we explained in the previous response, both voltage and membrane stretch activate OSCA/TMEM63A channels. We found measuring voltage dependence under constant pressure provided more consistent quantification than the gold standard pressure response protocol. This may be due to the variability of applied membrane tension under repeated stretches versus the more consistent applied voltage. Additionally, we chose -50 mmHg and -80 mmHg to reflect the reported differences in half-maximal pressures between OSCA1.2 and TMEM63A (e.g., P50 ~55 mmHg for 1.2 and ~61 mmHg for 63A in 10.7554/eLife.41844 versus ~86 mmHg for 1.2 and -123 mmHg for 63A in 10.1016/j.neuron.2023.07.006).
We also used higher pressure in cell attached mode to increase TMEM63A current amplitudes, which are usually tiny. We have updated our method section (Lines 329334) to further clarify why we used these protocols.
Please note that in TMEM16 proteins, ions and lipids might not always co-transport.
This means that under certain conditions, only one type of substrate may go through. For instance, in WT TMEM16F, Ca2+ stimulation can easily trigger PS exposure at resting membrane potential. No ionic currents are elicited until strong depolarization is applied. Similarly, the TMEM16F GOF mutations spontaneously transport lipids, leading to loss of lipid asymmetry (Fig. 1b, c). However, in 0 Ca2+, these TMEM16F mutant channels still need strong depolarization for ion conduction (Fig. 1d, e). Although the detailed mechanism still needs to be further investigated, the OSCA1.2 and TMEM63A GOF mutations share similar features with TMEM16 proteins, exhibiting ion conduction under high pressures and depolarizing voltages, yet constitutively active scrambling.
Some clarity is needed for their choice of residues. I understand that a lot of this is also informed by the structures of these ion channels. According to the alignment shown in Supplementary Figure 1, they chose LA for OSCA1.2, which is in line with the IM (TMEM16F) and II(TMEM16A) residues but for Tmem63a they chose the hydrophobic gate residue W and S. Was the A476 tested? Also, OSCA1.2 already has a K in the hydrophobic gating residue region. How do the authors reconcile this with their model?
We appreciate this critical comment. We have included the characterization of TMEM63A A476K (Fig. 6, corresponding to M522 in 16F, I547 in 16A, and A439 in OSCA1.2). Interestingly, A476K transfected cells did not show obvious spontaneous PS exposure yet exhibited a modest shift in V50 comparable to W472K and S475K. These differences may reflect the high-tension activated nature of the TMEM63 proteins (10.1016/j.neuron.2023.07.006) as compared to OSCA1.2, where the corresponding mutation (A439K, Fig. 4b, c) showed very little spontaneous activity and required hypotonic stimulation to promote more robust PS exposure (Fig. 5).
Furthermore, as we showed in Figs. 1b-c and 3b-c, there is a lower limit (towards the Cterminus) of the TM 4 lysine mutation effect, which becomes insufficient to cause a constitutively open pore for spontaneous lipid scrambling. It is possible that TMEM63A A476K represents the lower limit of TM 4 mutations that can convert TMEM63A into a spontaneous lipid scramblase.
Regarding OSCA1.2 K435 and TMEM63A W472, these sites correspond to the hydrophobic gate residues on TM 4 in TMEM16F (F518, Fig. 1a) and TMEM16A (L543, Fig. 3a) so it is unsurprising to us that a lysine mutation at this site causes constitutive scramblase activity in TMEM63A (Fig. 6b, c). For OSCA1.2, it is more intriguing since this residue is already a lysine (K435). In Supplementary Fig. 5 our new experiments show that neutralizing K435 with leucine (K435L) in the background of L438K significantly attenuates spontaneous PS exposure from ~63% PS positive for L438K alone (two lysine residues) to ~31% for K435L/L438K (one lysine). One the other hand, the K435L mutation by itself is also insufficient to induce PS exposure. Therefore, the endogenous lysine at residue 435 has an additive effect on the spontaneous scramblase activity of L438K. We believe the explanation for this result lies in experiments conducted in model transmembrane helices, which have shown that stacking hydrophilic side chains within the membrane interior promotes trans-bilayer lipid flipping (see 10.1248/cpb.c22-00133).
These same studies also support our observation (10.1038/s41467-019-09778-7) that highly hydrophilic side chains (such as lysine or glutamic acid) accelerate trans-bilayer lipid flipping more effectively than hydrophobic side chains such as isoleucine or alanine (Author response image 3, see also 10.1021/acs.jpcb.8b00298).
Author response image 3.
Trans-bilayer lipid flipping rates (kflip) accelerate with increasing side chain hydropathy for a residue placed in the center of a model transmembrane helical peptide
How do the authors know that osmotic shock is indeed activating OSCA1.2 and TMEM63A? If they can record from the channels then electrophysiology data that confirms activation of the channel in the presence of hypoosmotic shock will strengthen the osmolarity active scramblase activity demonstrated in Figure 4. So far, there is conclusive data showing that they are mechanically activated but conclusive electrophysiological data for OSCA/TMEM63 osmolarity activation is not described yet, including the reference (38) they indicate in line 132. Although osmotic shock can perturb mechanical properties of the membrane it can also activate volume-regulated anion channels, which are also present in HEK cells.
Thank you for raising this important question. While reference 38, (now reference 39) shows direct electrophysiological evidence of hypertonicity-induced current (e.g., Fig. 4 f, g, i, and j in 10.1038/nature13593), direct electrophysiological evidence that OSCA/TMEM63 can be activated by hypotonic stimulation is still missing. To address this question, we conducted whole-cell patch clamp experiments on mocktransfected and OSCA1.2 WT-transfected cells stimulated with 120 mOsm/kg hypotonic solution, comparable to the same conditions as hypotonic-induced scrambling shown in Fig. 5. As shown in Supplementary Fig. 6, our whole-cell recording detected a slowly evolving yet robust outward rectifying current in OSCA1.2-transfected cells, which was not observed in mock transfected cells.
To avoid the contamination from endogenous SWELL osmo-/volume-regulated chloride channels, our new experiment used 140 mM Na gluconate to replace NaCl in both the pipette and the bath solution. Because SWELL/VRAC channels are minimally permeable to gluconate anions (e.g., 10.1007/BF00374290), we conclude that hypotonic stimulation can indeed activate OSCA1.2 albeit with perhaps lower efficiency compared to mechanical stimulation.
Minor comments
What is the timeline for the scramblase assay for all the experiments (except Figure 4)? How long is the AnnexinV incubated before imaging?
Thank you for pointing out this point where we have not provided sufficient detail. Cells were imaged in the scramblase assay (including in Fig. 4, now revised Fig. 5) in AnnexinV-containing buffer immediately and without a formal incubation period because AnnexinV binding to exposed PS proceeds rapidly. We have included additional detail in the methods section to eliminate any confusion (Lines 310-312).
In some places of the document, it says OSCA/TMEM63, and in other places, it is denoted as TMEM63/OSCA. The literature so far has always called the family OSCA/TMEM63- please stay consistent with the field.
Thank you for pointing this out, we have corrected these instances to be consistent with the field.
Reviewer #2 (Recommendations For The Authors):
(1) The authors' statement that the channel/scramblase family members have a relatively low "energetic barrier for scramblase" activity needs further support. While mutating the hydrophobic channel gate certainly could destabilize ion conduction to cause a GOF effect on channel activity, it is still not clear why scramblase activity, which is tantamount to altered permeation, happens in the mutant channels. Are permeation and channel gating (opening) coupled in these channels? If so, what is the basis for the coupling? Is scramblase activity only observed when the gating is destabilized or are they separable?
We appreciate these great questions. For the question about the ‘energetic barrier’ statement, please see our response to point (3) where we have carried out MD simulations of the OSCA1.2 WT and L438K mutant to provide insight into how the permeation pathway is altered by these mutations.
Regarding why TMEM16A can be converted into a scramblase, we use the extensively studied TMEM16 proteins as examples to improve our current understanding of OSCA/TMEM63 proteins. For further details please see our original paper (10.1038/s41467-019-09778-7) and our review (10.3389/fphys.2021.787773), which are summarized as follows:
(1) The “neck region”, consisting of the exofacial halves of TMs 3-6, form the poregate region for both ion and lipid permeation (Author response image 4B). In the closed state, the neck region is constricted and TMs 4 and 6 interact with each other, preventing substrate permeation. The hydrophobic inner activation gate that we identified (10.1038/s41467-019-09778-7) resides right underneath the inner mouth of the neck region, controlling both ion and lipid permeation scrambling.
(2) Based on our functional observations and the available scramblase structures of TMEM16 proteins in multiple conformations, we proposed a clamshell-like gating model to describe TMEM16 lipid scrambling (Author response image 4D). According to this model, Ca2+-induced conformational changes weaken the TM 4/6 interface. This promotes the separation of the two transmembrane segments, analogous to the opening of a clam shell, allowing a membrane-spanning groove to facilitate permeation of the lipid headgroup.
(3) For the CaCC, TMEM16A, Ca2+ binding dilates the pore. However, the binding energy likely cannot open the TM 4/6 interface at the neck region so, in the absence of groove formation, only Cl- ions but not lipids can permeate. (Pore dilation model, Author response image 4C).
(4) Introducing charged residues near the inner activation gate disrupts the neck region, potentially by weakening the hydrophobic interactions between TMs 4 and 6. This mutational effect results in constitutively active TMEM16F scramblases and enables spontaneous lipid permeation in the TMEM16A CaCC.
(5) In our revision, we tested additional mutations with different side chain properties (Supplementary Fig. 2), validating previous findings by us (10.1038/s41467-01909778-7) and others (10.1038/s41467-022-34497-x) that gate disruption increases with the side chain hydropathy of the mutation.
(6) We further extended lysine mutations to two helical turns below the inner activation gate on TM 4 and identified a lower limit for mutation-induced spontaneous scramblase activity in TMEM16F and TMEM16A (Figs. 1b, c and 3b, c, respectively). Together, all these points lend additional support to our proposed gating models for TMEM16 proteins, which we postulate may also relate to the OSCA/TMEM63 family based on the evidence provided in our manuscript.
Author response image 4
Model of gating (and regulatory) mechanisms in the TMEM16 family. (B) overall architecture and proposed modules, (C) pore-dilation gating model for CaCCs, (D) Clamshell gating model for CaPLSases.
Regarding the relationship between ion and lipid permeation through TMEM16 scramblases, the following is the summary of our current understanding:
(1) Functionally, ion and lipid permeation are not necessarily obligatory to each other. This is evidenced by our previous biophysical characterizations of TMEM16F ion channel and lipid scramblase activities. Ca2+ can trigger TMEM16F lipid scrambling at resting membrane potentials, however, Ca2+ alone is insufficient to record TMEM16F current. Strong membrane depolarization synergistically with elevated intracellular Ca2+ is required to activate ion permeation. Based on these observations, we postulate that ions and lipids may have different extracellular gates, despite sharing an inner activation gate (10.1038/s41467-019-09778-7). Ca2+ alone may sufficiently open the inner gate (and extracellular gate) for lipids, whereas depolarization is likely required to open the extracellular gate and allow ion flux. Further structure-function studies are needed to test this hypothesis.
(2) Structurally, the open conformation of TMEM16 scramblases such as the fungal orthologs and human TMEM16K (Supplementary Fig. 1 b-d) are widely open, which allows lipid and ion co-transport. Ion and lipid co-transport has also been demonstrated in various MD simulations (e.g., 10.7554/eLife.28671, 10.3389/fmolb.2022.903972, and 10.1038/s41467-021-22724-w)
(3) Functionally, we (10.1085/jgp.202012704) and others (10.7554/eLife.06901.001) have measured dual recording of channel and scramblase activities, also demonstrating that ions and lipids are co-transported simultaneously when the proteins are fully activated.
(4) In this manuscript, we also provide multiple examples (TMEM16F in Fig. 1, TMEM16A in Fig. 3, OSCA1.2 in Fig. 4, and TMEM63A in Fig. 6) of mutations showing spontaneous phospholipid scramblase activities, yet their channel activities require strong depolarization or, in the case of TMEM63A, high pressures to be elicited.
Together, this new evidence further supports our hypothesis that there might be multiple gates for ion and lipid permeation, in addition to the shared inner gate we previously identified. We hope these detailed explanations help convey the intricacy of these intriguing questions. Of course, future studies are needed to test our hypothesis and elucidate the complex relationship between ion and lipid permeation of these proteins.
(2) One weakness in the experimental approach is the very limited number of substitutions used to infer the conclusion regarding the energetic barrier and other conclusions relating to scramblase activity. Additional substitutions of charged and polar amino acids at the hydrophobic gate would be helpful in illuminating the molecular determinants of the GOF phenotype and also reveal varying patterns of lipid permeation which could be enormously informative. These additional mutations for analysis of TMEM16F and OSCA should be added to the study.
We appreciate these great suggestions which were shared by multiple reviewers. We have included our duplicated response below.
“Response to reviewers 2 & 3: In our 2019 paper (10.1038/s41467-019-09778-7), we have systematically tested the side chain properties at the inner activation gate of TMEM16F on lipid scrambling activity (Response Fig. 6) and, since then, these results have been supplemented by others as well (10.1038/s41467-022-34497-x). In summary, mutating the inner activation gate residues to polar or charged residues generally results in constitutively activated scramblases without requiring Ca2+ (Fig 5a in 10.1038/s41467-019-09778-7). Because these residues form a hydrophobic gate, introducing smaller side chains via alanine substitution are also gain-of-function with the Y563A mutant as well as the F518A/Y563A/I612A variant being constitutively active (Fig. 3a in 10.1038/s41467-019-09778-7). Meanwhile, mutating these gate residues to hydrophobic amino acids causes no change for I612W, a slight gain-of-function for F518W, slight loss-of-function of F518L, and complete loss-of-function for Y563W (Fig. 4b in 10.1038/s41467-01909778-7). These findings clearly demonstrate that the side-chain properties are critical for regulating the gate opening. Charged mutations including lysine and glutamic acid are the most effective to promote gate opening (Fig 5a in 10.1038/s41467-019-09778-7).
Similarly, others have observed that side chain hydropathy at the F518 site in TMEM16F correlates with shifts in the Ca2+ EC50 (Fig. 2 of 10.1038/s41467-022-34497-x). Note that this publication resolved the structure of the TMEM16F F518H mutant, revealing a previously unseen conformation that we have highlighted in Supplementary Fig. 1e and discussed in lines 235-238. Please also see our response to Reviewer #1 above, where we discuss discoveries in model transmembrane helical peptide systems showing that transbilayer lipid flipping rates correlate with side chain hydropathy (Author response image 3), distance between stacked hydropathic residues (schematic in 10.1248/cpb.c22-00133), and even helical angle between stacked side chains (not show).
Following the reviewers’ suggestions, we have tested additional mutations in alternative locations and with different side chains.
(1) We have added data for TMEM16F I521A and I521E to demonstrate a similar effect of alternative side chains to what has previously been reported by us and others. We found that I521A failed to show spontaneous scrambling activity (Supplementary Fig. 2), yet I521E (Supplementary Fig. 2) is a constitutively active lipid scramblase, similar to I521K (Fig. 1). This further demonstrates that gate disruption correlates with the side chain hydropathy and that this site lines a critical gating interface.
(2) We also added lysine mutations two helical turns below the conserved inner activation gate for TMEM16F T526 (Fig. 1), TMEM16A E551 (Fig. 3). We found that there is indeed a lower limit for the observed effect in TMEM16, where lysine mutations no longer induce spontaneous lipid scrambling activity. This indicates that when TM 4/6 interaction is weaker toward intracellular side (Figs. 1a, 3a), the TM 4 lysine mutation loses the ability to promoting lipid scrambling by disrupting the TM 4/6 interface to enable clamshell-like opening of the permeation pathway.
(3) We added a TMEM16F lysine mutation on TM 6 at residue I611 (Fig. 2). Similar to I612K (Response Fig. 6), I611K also leads to spontaneous lipid scrambling and enhanced channel activity in the absence of calcium (Fig. 2). This shows that charged mutations along TM 6 can also promote lipid scrambling, strengthening our model that hydrophobic interactions along the TM 4/6 interface are critical for gating and lipid permeation.”
(3) Related to the above point, it would be enormously useful to perform even limited computational modelling to support the "energetic barrier" statement. Specifically, can the authors model waters in the putative pore to examine water occupancy in the WT and mutant channels to better understand how the barrier for ions and lipids is altered in the TMEM16?
We appreciate this suggestion and have now conducted atomistic MD simulations of OSCA1.2 WT and L438K mutant for ~1 μs (Supplementary Fig. 4). The simulations revealed, elevated water occupancy in the pore region of the L438K mutant, likely due to a widening at the TM 4/6 interface. Conversely, the WT interface remained constricted, largely disallowing water occupancy. These computational results support our previously proposed clamshell-like gating model for TMEM16 scramblases and provide strong support that the L438K mutation is disrupting the interaction of the TM 4/6 interface, in turn reducing the energetic barrier for both ion and lipid permeation.
(4) I am puzzled about the ability of OSCA and the TMEM63 proteins which are cation channels to conduct negatively charged lipids. How can the pore be selective for cations and yet permeate negatively charged molecules when lipids are presented?
This is a great question. TMEM16 scramblase (as well as other known scramblases, such as the Xkr and Opsin families) are surprisingly non-selective to phospholipids (all major phospholipid species, not just anionic lipids like PS). It is still debated whether lipid headgroups indeed insert into an open pore or hydrophilic groove (Response Fig. 5), or if they may traverse the bilayer by the so-called ‘out-of-groove’ model. Regardless of the model, the consensus is that Ca2+-induced conformational changes catalyze lipid permeation and the mutations we have introduced are designed to mimic these conformational changes by separating the TM 4/6 interface.
Additionally, TMEM16F channel activity was first characterized as cation non-selective (10.1016/j.cell.2012.07.036), similar to OSCA/TMEM63s, which may even exhibit some chloride permeability (10.7554/eLife.41844.001). Thus, it appears as though scramblase activity is agnostic to headgroup charge and compatible with both a mutant anion channel (TMEM16A) and mutant cation channels (TMEM16F, OSCA1.2, and TMEM63A), however, more detailed structural, functional, and computational studies are needed to further clarify ion and lipid co-transport mechanisms.
(5) Do pore blockers like Gd3+ which block permeation also inhibit the scramblase activity of the mutant channels? This should be tested for the mutant channels.
While extracellular Gd3+ has been previously reported as an inhibitor of OSCA1.2 (10.7554/eLife.41844.001), we did not observe this effect (Author response image 5), but instead saw inhibition by intracellular Gd3+ (Author response image 6). Given this discrepancy, we did not test Gd3+ inhibition of the OSCA1.2 scramblases, but instead tested Ani9, a paralog-specific inhibitor of TMEM16A, on the TMEM16A I546K gain-offunction and found it attenuated both ion channel and phospholipid scramblase activities (Supplementary Fig. 3).
Author response image 5.
200 µM Gd3+ext fails to inhibit OSCA1.2 currents in cell-attached patches. Pressure-elicited peak currents (n=6 each). Statistical test is an unpaired Student’s t-test.
Author response image 6.
200 µM Gd3+int completely inhibits OSCA1.2 currents in inside-out patches. (a) representative traces in before (black), during (red), and after (blue) Gd3+ application. (b) Representative application timecourse. (c) Quantification of peak currents (n=8 each). Statistical test is one-way ANOVA.
Minor:
- Some of the current amplitudes shown in Figures 2 and 3 are enormous. Is liquid junction potential corrected in these experiments? If not, it would be preferable to correct this to avoid voltage errors.
Thanks for the question. The large current amplitude is due to 1) great surface expression of the proteins; 2) large single channel conductance of OSCA channels, 3) much larger current at positive voltages for OSCA channels. Our control experiment showed that WT TMEM16A at 0 Ca2+ did not give rise to any current (Fig. 3d), further demonstrating that the large current was not due to liquid junction potential. For the OSCA recordings, we also did not observe current in mock-transfected cells, further excluding the possible interference of liquid junction potential (Response Fig. 1)
- Related, authors could consider adding some evidence using selective pharmacology to support the conclusions that the observed currents arise from TMEM or OSCA channels.
Thanks for the suggestion. As mentioned above, we have added experiments with Ani9, a specific inhibitor of TMEM16A, in Supplementary Fig. 3. We found that Ani9 robustly attenuated both ion channel and phospholipid scramblase activities for the TMEM16A I546K gain-of-function mutant. This is also consistent with our previous publication (10.1038/s41467-019-09778-7), where Ani9 efficiently inhibited the TMEM16A L534K mutant scramblases. Additionally, we have provided mock controls (Response Fig. 1, Fig. 6d, e) to show that the observed currents are indeed attributable to OSCA1.2 and TMEM63A.
Reviewer #3 (Recommendations For The Authors):
Given that the authors postulate that the introduction of a positive charge via the lysine side chain is essential to the constitutive activity of these proteins, additional mutation controls for side chain size (e.g. glutamine/methionine) or negative charge (e.g. glutamic acid), or a different positive charge (i.e. arginine) would have strengthened their argument. To more comprehensively understand the TM4/TM6 interface, mutations at locations one turn above and one turn below could be studied until there is no phenotype. In addition, the equivalent mutations on the TM6 side should be explored to rule out the effects of conformational changes that arise from mutating TM4 and to increase the strength of evidence for the importance of side-chain interactions at the TM6 interface.
We appreciate these great suggestions which were shared by multiple reviewers. We have included our previous responses below.
“Response to reviewers 2 & 3: In our 2019 paper (10.1038/s41467-019-09778-7), we have systematically tested the side chain properties at the inner activation gate of TMEM16F on lipid scrambling activity (Response Fig. 6) and, since then, these results have been supplemented by others as well (10.1038/s41467-022-34497-x). In summary, mutating the inner activation gate residues to polar or charged residues generally results in constitutively activated scramblases without requiring Ca2+ (Fig 5a in 10.1038/s41467-019-09778-7). Because these residues form a hydrophobic gate, introducing smaller side chains via alanine substitution are also gain-of-function with the Y563A mutant as well as the F518A/Y563A/I612A variant being constitutively active (Fig. 3a in 10.1038/s41467-019-09778-7). Meanwhile, mutating these gate residues to hydrophobic amino acids causes no change for I612W, a slight gain-of-function for F518W, slight loss-of-function of F518L, and complete loss-of-function for Y563W (Fig. 4b in 10.1038/s41467-01909778-7). These findings clearly demonstrate that the side-chain properties are critical for regulating the gate opening. Charged mutations including lysine and glutamic acid are the most effective to promote gate opening (Fig 5a in 10.1038/s41467-019-09778-7).
Similarly, others have observed that side chain hydropathy at the F518 site in TMEM16F correlates with shifts in the Ca2+ EC50 (Fig. 2 of 10.1038/s41467-022-34497-x). Note that this publication resolved the structure of the TMEM16F F518H mutant, revealing a previously unseen conformation that we have highlighted in Supplementary Fig. 1e and discussed in lines 235-238. Please also see our response to Reviewer #1 above, where we discuss discoveries in model transmembrane helical peptide systems showing that transbilayer lipid flipping rates correlate with side chain hydropathy (Author response image 3), distance between stacked hydropathic residues (schematic in 10.1248/cpb.c22-00133), and even helical angle between stacked side chains (not show).
Following the reviewers’ suggestions, we have tested additional mutations in alternative locations and with different side chains.
(1) We have added data for TMEM16F I521A and I521E to demonstrate a similar effect of alternative side chains to what has previously been reported by us and others. We found that I521A failed to show spontaneous scrambling activity (Supplementary Fig. 2), yet I521E (Supplementary Fig. 2) is a constitutively active lipid scramblase, similar to I521K (Fig. 1). This further demonstrates that gate disruption correlates with the side chain hydropathy and that this site lines a critical gating interface.
(2) We also added lysine mutations two helical turns below the conserved inner activation gate for TMEM16F T526 (Fig. 1), TMEM16A E551 (Fig. 3). We found that there is indeed a lower limit for the observed effect in TMEM16, where lysine mutations no longer induce spontaneous lipid scrambling activity. This indicates that when TM 4/6 interaction is weaker toward intracellular side (Figs. 1a, 3a), the TM 4 lysine mutation loses the ability to promoting lipid scrambling by disrupting the TM 4/6 interface to enable clamshell-like opening of the permeation pathway.
(3) We added a TMEM16F lysine mutation on TM 6 at residue I611 (Fig. 2). Similar to I612K (Response Fig. 6), I611K also leads to spontaneous lipid scrambling and enhanced channel activity in the absence of calcium (Fig. 2). This shows that charged mutations along TM 6 can also promote lipid scrambling, strengthening our model that hydrophobic interactions along the TM 4/6 interface are critical for gating and lipid permeation.”
The experiments for OSCA1.2 osmolarity effects on gating and scramblase in Figure 4 could be improved by adding different levels of osmolarity in addition to time in the hypotonic solution.
We thank the reviewer for this excellent suggestion. We extensively tested this idea and found evidence (Response Fig. 10) that intermediate osmolarity (220 and 180 mOso/kg) also can enhance the scramblase activity of the A439K mutant, albeit to a milder extent compared to 120 mOso/kg stimulation. This suggests that swellinginduced membrane stretch may proportionally induce A439K activation and lipid scrambling. Due to the relatively mild sensitivity of OSCA to osmolarity and the variations induced by the experimental conditions, we believe it is better to not include this data to avoid overclaiming. We hope the reviewer would agree.
Author response image 7.
AnV intensities of WT- and A439K-transfected cells after 10 minutes of hypotonic stimulation at the listed osmolarities.
Some confocal images appear to be rotated relative to each other (e.g. Figures 2b and 3b).
Thank you for identifying these errors, they are corrected in the revision.
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eLife Assessment
This important study advances our understanding of the mechanisms controlling lipid flux and ion permeation in the TMEM16 and OSCA/TMEM63 family channels. The study provides compelling new evidence indicating that side chains along the TM4/6 interface play a key role in gating lipid and ion fluxes in these channels. The authors suggest that the transmembrane channel/scramblase family proteins may have originally functioned as scramblases but lost this capacity over evolution.
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Reviewer #1 (Public review):
Summary:
TMEM16, OSCA/TMEM63, and TMC belong to a large superfamily of ion channels where TMEM16 members are calcium activated lipid scramblases and chloride channels, whereas OSCA/TMEM63 and TMCs are mechanically activated ion channels. In the TMEM16 family, TMEM16F is a well characterized calcium activated lipid scramblase that play an important role in processes like blood coagulation, cell death signaling, and phagocytosis. In a previous study the group has demonstrated that lysine mutation in TM4 of TMEM16A can enable the calcium activated chloride channel to permeate phospholipids too. Based on this they hypothesize that the energy barrier for lipid scramblase in these ion channels is low, and that modification in the hydrophobic gate region by introducing a charged side chain between TM4/6 interface in TMEM16 and OSCA/TMEM63 family can allow lipid scramblase. In this manuscript, using scramblase activity via Annexin V binding to phosphatidylserine, and electrophysiology, the authors demonstrate that lysine mutation in TM4 of TMEM16F and TMEM16A can cause constitutive lipid scramblase activity. The authors then go on to show that analogous mutations in OSCA1.2 and TMEM63A can lead to scramblase activity. The revised version does a thorough characterization of residues that form the hydrophobic gate region in TM4/6 of this superfamily of channels. Their results indicated that disrupting the TM4/6 interaction can reduce energy barrier for this channels to scramblase lipids.
Strengths:
Overall, the authors introduce an interesting concept that this large superfamily can permeate ions and lipids.
Weaknesses:
none noted in the revised version.
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Reviewer #2 (Public review):
This focused study by Lowry and colleagues that identifies a key molecular motif that controls ion permeation vs combined ion permeation and lipid transport in three families of channel/scramblase proteins, in TMEM16 channels, in the plant-expressed and stress-gated cation channel OSCA, and in the mammalian homolog and mechanosensitive cation channel, TMEM63. Between them, these three channels share low sequence similarity and have seemingly differing functions, as anion (TMEM16 channels), or stress-activated cation channels (OSCA/TMEM63). The study finds that in all three families, mutating a single hydrophobic residue in the ion permeation pathway of the channels confers lipid transport through the pores of the channels, indicating that TMEM16 and related OSCA and TMEM63 channels have a conserved potential for both ion and lipid permeation. The authors interpret the findings as revealing that these channel/scramblase proteins have a relatively low "energetic barrier for scramblase" activity. The experiments are done with a high level of rigor and the revised paper is very well written and addresses the previous concerns.
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Reviewer #3 (Public review):
This study was focused on the conserved mechanisms across the Transmembrane Channel/Scramblase superfamily, which includes members of the TMEM16, TMEM63/OSCA, and TMC families. In previous work, the authors have studied the role of the inner activation gate of these proteins. Here, the authors show that the introduction of mutations at the TM4-TM6 interface, which are close to the inactivation gate, can disrupt gating and confer scramblase activity to non-scramblases proteins.
Overall, the confocal imaging experiments, patch clamping experiments, and data analysis are performed well and in line with standard methods. The molecular dynamics simulation work is focused but adds supportive evidence to their findings. Although there could have been more extensive molecular analysis to bolster the authors' arguments on the role of the TM4-TM6 interface (e.g. evaluate effects of size/hydrophobicity, double mutants, cross-linking, more in-depth simulation data), there is adequate evidence to conclude that certain residues at this interface is critical to ion conduction and phospholipid scramblase activity. The data presented only adds incremental depth of knowledge for each individual channel, but together, they show this to be true for conserved TM4 residues across TMEM16F, TMEM16A, OSCA1.2, and TMEM63A proteins. This breadth of data is a major strength of this paper, and provides strong evidence for a coupled pathway for ion conduction and phospholipid transport, though the underlying biophysical mechanism is still speculative and remains to be elucidated.
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ucla-biostat-216.github.io ucla-biostat-216.github.io
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a set of vectors
Change to "... a non-empty set of vectors" for clarity?
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social-media-ethics-automation.github.io social-media-ethics-automation.github.io
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Anonymity can also encourage authentic behavior.
It is for this reason I feel that people are resistant to ID requirements to sign up for a social media. Many countries are considering requiring a driver's license or ID to access 18+ or even 13+ material. While even an email could possibly provide a name via a thorough investigation, it's still a manual barrier that prevents a hacker to easily dox large groups of people. However providing legal name and address to a third-party platform holder, even if secure, gives each user 1 less layer of protection in case of a data breach. (Not to mention that people already view platform holders as THE antagonistic force.)
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6.6.3. Is authentic self-expression good?#
It's important to think about the circumstances in which this genuine behavior occurs. People can express their "true" opinions and sentiments in an anonymous setting, but there may be no real repercussions. In a more accountable, face-to-face setting, impulsive, raw emotion may not always be indicative of an individual's basic principles, and the lack of responsibility may make it difficult to distinguish between the two types of self-expression.
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Does anonymity discourage authenticity and encourage inauthentic behavior?
Anonymity can both discourage authenticity and encourage inauthentic behavior, depending on the context and the individuals involved. On one hand, anonymity can create a sense of freedom, allowing people to express thoughts and opinions they might suppress in real life due to fear of judgment or consequences. On the other hand, the lack of accountability that comes with anonymity can also lead to inauthentic or even harmful behavior.
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Local file Local file
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HEENT
HEENT = everything normal, non-remkarable
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www.planalto.gov.br www.planalto.gov.br
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Defensoria Pública
Entendimento do STF: é devido o pagamento de honorários sucumbenciais à Defensoria Pública, quando representa parte vencedora em demanda ajuizada contra qualquer ente público, inclusive aquele que integra → ⚠ cancelamento da Súmula 421 do STF
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social-media-ethics-automation.github.io social-media-ethics-automation.github.io
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(lonelygirl15)
lonelygirl15 was one of the first major examples of the "Unreality" genre on the internet, following the footsteps of Blair Witch Project and inspiring future works like Slenderman. The appeal of unreality is similar to satire, tricking the audience into believing what they were watching was real, but for suspense or horror instead of comedy. But understandably, for those who aren't "in on it" can feel betrayed if what they were being fed was a lie, especially in the infancy of a new medium (online video).
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Early in the days of YouTube, one YouTube channel (lonelygirl15) started to release vlogs (video web logs) consisting of a girl in her room giving updates on the mundane dramas of her life. But as the channel continued posting videos and gaining popularity, viewers started to question if the events being told in the vlogs were true stories, or if they were fictional. Eventually, users discovered that it was a fictional show, and the girl giving the updates was an actress. Many users were upset that what they had been watching wasn’t authentic. That is, users believed the channel was presenting itself as true events about a real girl, and it wasn’t that at all. Though, even after users discovered it was fictional, the channel continued to grow in popularity.
This reminds me of an internet celebrity I knew before. She uploaded a video about picking up elementary school students' homework in Paris, and this video caused a big sensation on the video website. But later it was discovered that her video was self-directed and self-acted. She gained huge traffic with a video, but in the end her social platform account was blocked for spreading false facts.
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That means that both of us have an incentive not to betray or take advantage of each other, for our mutual protection.
Long-standing social relations have led to the result that direct communication between people and cooperation is based on honesty, so that society can develop in the long term, therefore, when one of the two parties has a problem with honesty, it will immediately lead to a breakdown of the relationship and the transaction stops, which is why the society has to make rules to restrain people.
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Though, even after users discovered it was fictional, the channel continued to grow in popularity.
When people have realized that the girl's behavior is acting, virtual and not real, why do they continue to watch while allowing the girl's channel to continue to explode in popularity, my personal opinion is that on the internet, the line of judging authenticity has become relatively blurred as most of the views are that most of the content on the internet is virtual, and that when the girl's behavior doesn't live up to the fraudulent When the girl's behavior does not amount to fraud, people will choose to forgive her.
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docdrop.org docdrop.org
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Helena provides an example of how Asian Americans are often classed together by others. Some white classmates did not bother to find out that she was Korean. When discussing such events, Helena, like other respondents, is still in pain from them and has a difficult time making eye contact. She keeps her head down and speaks softly, crying a few times as she recounts painful memories. She was not accepted for being the smart, high-achieving youngster she was, but was ostra-cized for her intelligence and identity
This statement is deeply impactful as it highlights the pain and alienation that Helena, as an Asian American, has experienced due to being grouped together with others based on superficial perceptions and stereotypes. It emphasizes how often people don't take the time to understand individual differences in Asian American communities, leading to feelings of being misunderstood and isolated. Helena's experience demonstrates the emotional toll and the profound sense of exclusion that can result from such stereotyping and ignorance.
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are gradually introduced to racial socialization in peer groups. Young children’s racist behavior is often excused by adults on the grounds that children are naïve innocents and often slip and fall in the realm of social behavior, yet the assumption that children’s racist comments and actions are innocuous is incorrect. Based on extensive field research in a large child-care center, Debra Van Ausdale and Joe Feagin concluded that the “strongest evidence of white adults’ conceptual bia
I’m all for recognising that racist attitudes in children aren’t harmless. It makes me afraid of these behaviors being unchecked without early intervention. Children do experience this period of development of learning from and imitating. If we simply reject them as childish in the sense of not learning anything, then we are cutting off critical opportunities to teach them how to embrace difference.
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online.clackamas.edu online.clackamas.edu
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Picture 1
Concentration is measured in percentage, not g/mL (which represents density).
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www.youtube.com www.youtube.com
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Successful Secretary Presented by Royal Office Typewriters. A Thomas Craven Film Corporation Production, 1966. https://www.youtube.com/watch?v=If5b2FiDaLk.
Script: Lee Thuna<br /> Educational Consultant: Catharine Stevens<br /> Assistant Director: Willis F. Briley<br /> Design: Francisco Reynders<br /> Director & Producer: Carl A. Carbone<br /> A Thomas Craven Film Corporation Production
"Mother the mail"
gendered subservience
"coding boobytraps"
"I think you'll like the half sheet better. It is faster." —Mr. Typewriter, timestamp
A little bit of the tone of "HAL" from 2001: A Space Odyssey (1968). This is particularly suggestive as H.A.L. was a one letter increment from I.B.M. and the 1966 Royal 660 was designed to compete with IBM's Selectric
This calm voice makes suggestions to a secretary while H.A.L. does it for a male astronaut (a heroic figure of the time period). Suddenly the populace feels the computer might be a bad actor.
"We're living in an electric world, more speed and less effort."—Mr. Typewriter<br /> (techno-utopianism)
Tags
- typewriter shortcuts
- IBM selectric
- typewriter ads
- power over
- H.A.L.
- 1966
- typewriters
- Royal 660
- voice over
- Mr. Typewriter
- secretaries
- gendered subservience
- techno-utopianism
- efficiency
- Royal typewriters
- effort
- quotes
- artificial intelligence as overlord
- 2001: A Space Odyssey (1968)
Annotators
URL
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docdrop.org docdrop.org
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White Americans may prize Asian Americans relative to African Americans in certain limited ways so as to ensure white dominance over both. Whites may sometimes place or consider Asians “nearer to whites,” a relative valorization, because of Asian American achieve-ments in certain educational and economic areas. Yet this middling status is possible only because other Americans of color, such as African Americans or Mexican Americans, have been allowed fewer opportunities by whites. Whites’ use of Asian Americans as a measuring stick for other Americans of color is highly divisive, for it pits groups of color against each other, as well as isolates Asian Americans from white Americans.Kim underscores well the price paid
I find it odd that sometimes white Americans frame Asian Americans in such a way that makes them seem superior to other people of colour, particularly African Americans, as an extension of maintaining control over them. And yes, this strategy can divide minority groups into competing or competing for status or recognition in a white world order. Asian Americans being "nearer to whites" is often driven by a combination of academic and economic accomplishments that contrast the resentment against structural inequality among African Americans and other minorities who have enjoyed less.
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social science
I see that a number of Asian American researchers have indeed played a significant role in explaining Asian Americans’ adaptive disadvantages. It has been an innovator in illuminated racism and the oppressions faced by this community. Moreover, the fact that we’re less likely to explicitly cite whites as critical to generating and maintaining racist spaces parallels a trend in scholarship generally.
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These students have never been taught Asian American history, or been privy to significant events that have shaped these communities in the United States.
Something i found interesting was something is the way people still discriminate or push aside others peoples history which is still as important as any other history. I'm happy to see that in the school i work in because we are a diverse school, we tend to incorporate everyones culture, and we have the kids do culture projects in which they present where they're from and parents bring in food from their culture in which everyone gets to try.
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The white-created “suc-cessful model minority” stereotype made it difficult for non-Asians around her to see her illness and encouraged silence among the Asian Americans who knew her.
The fact that the reading calls out the standards Asian groups have to meet because it's a standard is interesting. It is something i've always hear of what people say from these groups, but the Asians i've met have always been the most hard working, but over work themselves through pressure because of their parents of their enviroment.
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often encourage my students to feel when we learn about inequality, because oppression works in a way so that we no longer feel empathy for target groups
This is something sad but important to know because suicide groups do not just focus on a certain groups but it can be any one generally. Here specifically talking about the Asian American groups, as of what i know or learned from, these groups are held to a high standard and discipline where it is sad seeing the results of it.
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As you all noticed I haven't given too much attention to this project in recent years, which I regret, but realistically I probably won't be the best maintainer given I haven't been using Ruby for years now, lost the contact with the ecosystem whatsoever.
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Local file Local file
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t’s why works can be organized by genre and subgenre; academics can propose grand unified theories ofliterature; folklorists can systematically classify thousands of recurring motifs in myths, legends, andfables around the world; and friends and algorithms can curate playlists of songs and stories just for you.And when repetition tends toward the formulaic, it’s also why AI can be used by Hollywood to “predict”a film’s performance based on its screenplay, by writers to churn out novels, and by researchersto manifest scientific papers.
author provided sources, is planned
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o claim that AI models like ChatGPT and DALL-E will replace art created bypeople is to ignore both the ineffable qualities of the human touch and the critical flaws of thesemodels—or so say the artists and writers.
Testing ideas
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beta.poetryfoundation.org beta.poetryfoundation.org
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The other kids stare like I’m some kind of freak—
Deserved if you messed something this important up
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I look like I’m recently back from the dead.
That he is ready for halloween
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I dyed my hair black, and I cut off my bangs.
This quote explains how dedicated the character was to their Halloween costume.
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Man, I look cool!
he was so excited to show off his costume.
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the halloween party ain't till next week. so he embbrassed himself??
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google.github.io google.github.io
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请注意,for 循环只迭代到 4。现在展示使用 1..=5 语法表示一个包含边界的范围。
有点特别
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www.nytimes.com www.nytimes.com
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Noch nicht peer-reviewte Studien sprechen dafür, dass die globale Erhitzung die Niederschläge durch den Hurrikan Milton um 20 und seine Windgeschwindigkeit um 10% gesteigert hat. Dles führte zu etwa doppelt so großen Zerstörungen als bei einem nicht von der Erhitzung beteuerten Sturm gleicher Seltenheit. https://www.nytimes.com/2024/10/11/climate/milton-climate-change.html
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Local file Local file
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Another reason why it saves time is that here you canimply things instead of having to express them in full,for your Card-System and its Headings need only to beclear to yourself (see p. 67), whereas a complete Essayor Speech must be in Sentences and must be clear toyour readers or hearers as well. In the Cards you canuse all kinds of Abbreviations (p. 70) : these, again,need only be clear to yourself.
Miles touches on the interplay of knowledge written down on index cards and the knowledge which is kept only in one's mind. Some practitioners in the space from 2013-2024 seem to imply that they're writing almost everything out in far deeper detail than Miles would indicate. In his incarnation, much of the knowledge might be more quickly indicated by a short sentence or heading which the brain can associate to longer explanations.
This sort of indexing is akin to some of the method potentially seen in Marshall Mathers' zettelkasten.
I'm creating a tag here for "card index for productivity" to track the idea of productivity in writing which I'm specifically using separately from the tag "card index as productivity system" which is used to describe their use for project tracking systems in systems like GTD, Memindex, etc.
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resulted in limiting inflammation
How would degranulation limit inflammation? The MCs are releasing pro-inflammatory cytokines, as you pointed out.
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Additionally, mast cells (MCs) were increased in the lungs of macaques with PTB
Consider including a quantification of the increase reported by Esaulova et al? It's always difficult to evaluate the importance of a finding like this without some appreciation of the magnitude of the change.
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x.com x.com
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The similarity is because they are all saying roughly the same thing: Total (result) = Kinetic (cost) + Potential (benefit) Cost is either imaginary squared or negative (space-like), benefit is real (time-like), result is mass-like. Just like physics, the economic unfavourable models are the negative results. In economics, diversity of products is a strength as it allows better recovery from failure of any one, comically DEI of people fails miserably at this, because all people are not equal. Here are some other examples you will know if you do physics: E² + (ipc)² = (mc²)² (relativistic Einstein equation), mass being the result, energy time-like (potential), momentum the space-like (kinetic). ∇² - 1/c² ∂²/∂t² = (mc/ℏ)² (Klein-Gordon equation), mass is the result, ∂²/∂t² potential, ∇² is kinetic. Finally we have Dirac equation, which unlike the previous two as "sum of squares" is more like vector addition (first order differentials, not second). iℏγ⁰∂₀ψ + iℏγⁱ∂ᵢψ = mcψ First part is still the time-like potential, second part is the space-like kinetic, and the mass is still the result though all the same. This is because energy is all forms, when on a flat (free from outside influence) worksheet, acts just like a triangle between potential, kinetic and resultant energies. E.g. it is always of the form k² + p² = r², quite often kinetic is imaginary to potential (+,-,-,-) spacetime metric, quaternion mathematics. So the r² can be negative, or imaginary result if costs out way benefits, or work in is greater than work out. Useless but still mathematical solution. Just like physics, you always want the mass or result to be positive and real, or your going to lose energy to the surrounding field, with negative returns. Economic net loss do not last long, just like imaginary particles in physics.
in reply to Cesar A. Hidalgo at https://x.com/realAnthonyDean/status/1844409919161684366
via Anthony Dean @realAnthonyDean
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www.youtube.com www.youtube.com
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Advanced Typing: Duplicating and Manuscript. Vol. MN-1512d, 1943. https://www.youtube.com/watch?v=7ve5JnTUzvo.
Stencils
Before writing stencils, be sure to clean your type. (Don't use liquid solvent.)
Be sure to place the cushion sheet properly behind the stencil.
Place the paper bail rollers at the extreme left and right of the stencil to prevent them from marking the master.
For errors, rub individual characters separately with a burnisher using a circular motion.
Hectograph masters, Hectograph ribbon (ditto ribbon)
Wax pencils
Typefaces
20% more type on a page with elite than 10 inch pica.
Pica allows approximately 26-40 lines on standard letterhead giving 300-450 words to a page.
Special characters: - o for degrees ' and " for feet and inches or minutes and seconds along with superscript - division: - backspace colon - pound sterling: L backspace f - exclamation point: period backspace ' - equal sign: hyphen backspace variable hyphen - paragraph mark: P backspace I
proofreaders' marks<br /> # followed by a number is used to mean insert that number of spaces
Centering timestamp 19:37
Tags
- wax pencils
- Underwood justifying typewriter
- typewriter stencils
- type styles
- burnisher
- offset masters
- Varityper
- Lenor Fenton
- typewriters
- elite
- watch
- dublicating
- Hectograph pencils
- Electromatic proportional spacing machine (typewriter)
- proofreading
- pica
- direct offset process
- ditto machines
- centering
- Hectograph masters
Annotators
URL
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www.calligraphr.com www.calligraphr.com
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https://www.calligraphr.com/en/
Can be used to digitize typewriter typefaces.
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doc-04-1g-prod-01-apps-viewer.googleusercontent.com doc-04-1g-prod-01-apps-viewer.googleusercontent.com
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"exemplary prophet.
ethical vs. exemplary prophet
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The prophet may be primarily, as in thelast cases, an instrument for the proclamation of a god and his will, bethis a concrete command or an abstract norm. Preaching as one who hasreceived a commission from god, he demands obedience as an ethical duty.This type we shall term the "ethical prophet." On the other hand, theprophet may be an exemplary man who, by his personal example,demonstrates to others the way to rdigious salvation, as in.the case of theBuddha.
Prophet can demand obedience on higher beings behalf or spread doctrine through exemplary lifestyles
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Ethical doctrine was lacking in the mystagogue, whodistributed magical salvation, or at least doctrine played only a verysubordinate role in his work. Instead, his primary gift waS hereditarilytransmitted magical art
Prophets require a mystical doctrine alongside magical acts- which mystagogues (or magicians) lack
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him
prophets gather people around them? Mystagouges don't?
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mystagogue
from internet- teacher or producer of mystical doctrine
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But the prophet, in our specialsense, is never to be found where the proclamatiQn of a religious truth ofsalvation through personal revelation is lacking. In our view, this quali6-cation must be regarded as the decisive hallmark of prophecy
No matter the semblance, religious truth and salvations defines prophetic schools from the most abstract schools of thought
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hat primarily differentiates such figures from the prophets is theirlack of that vital emotional preaching which is distinctive of prophecy,regardless of whether this is disseminated by the spoken word, thepamphlet, or any other type of literary compositio
philosophy or efforts towards social reform unattached to a doctrine can not be considered prophetic teachings
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t is characteristic of the prophets that they do not receive theirmission from any human agency, but seize it, as i~ were.
Not protecting human rights for the sake of human rights
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On the other hand, there are various transitional phases linking theprophet to the teacher of ethics, especially the teacher of social ethics.
teacher of ethics outgrowth of prophets??
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A merchant, he was first a leader of pietisticbourgeois conventicles in Mecca, until he realized more and more clearlythat the ideal external basis for his missionizing would be provided by theorganization of the interests of the warrior dans in the acquisition of booty
social reform all has charismatic orientation
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warriors
Jesus not concerned with social reform but other propehts of different religions were
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The Israelite prophets were concernedwith social and other types of injustice as a violation of the Mosaic codeprimarily in order to explain god's wrath, and not in order to institute aprogram of social reform
Most prophets trying to explain God's wrath through social injustice, not initiate social reform
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ut it must not be forgotten that in the motivation of the Israeliteprophets theSe social reforms were only means to an end. Their primaryconcern was with foreign politics, chieBy because it constituted thetheater of their god's activity.
all Israelite social reforms was for the sake of foreign policy
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Not only were none of the prophets aisymnetai in this sense, but ingeneral what ncnnally passes for prophecy does not belong to this cate-gory.
but, this behavior is not common among prophets
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It was Moses' great achieve-ment to find a compromise solution of, or prophylactic for, these conflicts(e.g., the seisachtheia of the Year of Release)4 and to o!':"ganize the Israeliteconfederacy with an integral national god
Moses transitioned from a prophet to lawgiver, finding solutions to economic conflict and oriented Israelites as a nation towards a god.
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The typical prophet propagates ideas for their own sake andnot for fees, at least not in any obvious or regulated form. The provisionsenjoining the non-remunerative character of prophetic propaganda havetaken various forms. Thus developed the carefully cultivated postulatethat the apostle, prophet, or teacher of ancient Christianity must not"trade on" his religious proclamations.
prophets are characteristically, not capitalizing on their skills and abilities
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On the other hand, .it was only under very unusual circumstancesthat a .prophet succeeded in establishing his authority without charis-matic authentication, which in practice meant" magic
Although not magicians, magic almost always involved in proving prophets legitimacy
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nd the core of his mission is doctrine or com-mandment, not magic
Prophets orientation is to a doctrine nit magic, self-interested supernatural actions
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The latter lays claim tt>authority by virtue of his service in a sacred tradition, while theprophet's daimis based on personal revelation and charisma
Priest gains credibility through servitude Prophet gains credibility through personal revelations and interpretations as well as charisma
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For our purposes here, the personal call is the decisive elementdistinguishing the prophet from the priest.
what we care about- what makes a prophet and what makes a priest?
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pletely new deliverances.
position of individual within the movement of a religion not relevant
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Along with the ideology of loyalty, which iscertainly by no means unimportant, allegiance to hereditary monarchy inparticular is very strongly influenced by the consideration that all in-herited and legitimately acquired property would be endangered ifpeople stopped believing in the sanctity of hereditary succession to th,ethrone.
fascinating- everything would go bad in a very physical and material sense if belief in whatever no longer existed, promotes people to give
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he most important ell:amples of deSignation of a successor by thecharil;matic followers of the leader are to be found in the election ofbishops, and particularly of the Pope, by the original system of designa-tion by the clergy and recognition by the lay community.
pop is the og designation of successor
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as held originally only by personal charismatic martyrs orascetics, hut became transfonned into a power of the office of bishopor priest
power to absolve people from sins passed down from ___ to the office individuals, bishop or priest
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It is thus a matter of the type of prestige enjoyed by rulinggroups. A hereditary monarch by "divine right" is not a simple patrimo-nial chief, patriarch, or sheik; a vassal is not a mere household retaineror official. Further details must be deferred to the analysis of statusgroups.
same groups different fonts? can't attain there power through rational or simply traditional means, charismatic involved somehow
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For charisma
charisma can only remain anti-economic for so long
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transformation
charismatic admin can become bureacratic
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benefices
charismatic admin can tax or require fees of members
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structure
begin to build other economic structures, less based on charismatic power
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The result is that all powers and advantages ofaU sorts become traditionalized, The heads of families, who al\t tradi-tional gerontocrats or patriarchs without personal charismatic~legitimacy,regulate the exercise of these powers which cannot be taken away fromtheir family. It is not the type of position he occupies which determinesthe rank of a man or of his family, but rather the hereditary charismaticrank of his family determines the position he will occupy
charismatic power transfers to traditionalized hereditary power over time
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Charismacan only be "awakened" and "tested"; it cannot be "learned" or "taught."
all charisma must be awakened (differ from like a monk)
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The concept that· charisma may be transmitted by ritual meansfrom one bearer to another or may be created in a new person. Theconcept was Originally magical. It involves a dissociation of charismafrom a particular individual" making it an objective, transferrable entity.In particular, it may become the charisma of office.
charisma can be transferable- making the charisma an object independent of the individual
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he conception that charisma is a quality transmitted by heredity;thus that it is participated in by the kinsmen of its bearer, particularly byhis dosest relatives.
sometimes charisma is hereditary
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Designation of a ~'.lCcessor by the charismatically qualified ad-ministrative staff and his recognition by the community.
can be designated by larger community
Annotators
URL
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viewer.athenadocs.nl viewer.athenadocs.nl
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GloCal was designed for this purpose and combines global (etic) and local (emic) elements.
Glocal (=globale en lokale elementen): - Etic: woordenboeken, eigenschappen reduceren via vertrouwdheid, persoonlijkheidseigenschappen verzamelen via andere instrumenten. - Emic: aanvullende metingen ter reducatie/ andere woorden mogelijk verwijderen, kwalitatieve gegevens via gesproken eigenschappen, en gegevens vergelijken met andere culturen.
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Nine distinct clusters were eventually found: • Conscientiousness • Emotional stability Tip! Remember that the CPAI is a combination of emic and etic approaches. The emic approach focuses on culture-specific characteristics, such as the unique factor of interpersonal connectedness in Chinese culture. The etic approach then tests these characteristics in other cultures, such as Chinese and European Americans. The exam may ask about how these approaches work together to understand personality differences across cultures. Week 3 – Personality 10 • Extraversion • Facilitation/relief (guiding others) • Integrity (honesty, reliability, loyalty) • Intellect (creativity, talent) • Openness • Relationship harmony (approachability, accessibility) • Gentleness (agreeableness, kindness)
9 clusters van SAPI: 1. Gewetensvolheid. 2. Emotionele stabiliteit. 3.. Extraversie. 4. Ontspanning. 5. Integriteit. 6. Intellect. 7. Openheid. 8. Relatieharmonie. 9. Zachtmoedigheid.
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Develop an indigenous theoretical model of personality, and • Develop a personality test that is not biased toward particular languages or ethnic groups in South Africa. This personality test would therefore comply with labor laws in South Africa.
Doelen van SAPI-project: - Inheemse theoretische model van persoonlijkheid ontwikkelen. - Persoonlijkheidstest ontwikkelen die onbevooroordeeld is.
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derived four factors: social potency, dependence, leniency and interpersonal connectedness
4 factoren van zelfbeschrijving: - Sociale potentie. - Afhankelijkheid. - Clementie (=zachtaardigheid). - Interpersoonlijke verbondenheid.
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Week 3 – Personality 9 Combined emic-etic approach
Perspectief van zowel binnenuit als buitenaf; hoe iemand iets zelf ervaart maar ook hoe iemand anders naar bepaalde realiteit kijkt.
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Emic approaches
Emic=perspectief van binnenuit; hoe iemand iets zelf ervaart, specifiek voor bepaalde groep.
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Selective migration of similar individuals.
Selectieve migratie van vergelijkbare individuen= (woon)plaatsen opzoeken op basis van vergelijkbare mensen (=qua persoonlijkheid).
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Culture forms personality through learning.
Cultuur maakt persoonlijkheid= gedrag aanleren door wat om je heen hierover gedeeld wordt.
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Methods are often not rigorous enough o It must be considered whether the new instrument actually adds something to relative to already existing instruments, this is called incremental validity
Twijfelpunten emic approach: - Methoden zijn vaak niet rigoureus (=streng) genoeg. - Nieuwe instrument heroverwegen; incrementele validiteit.
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Emic
Emic=perspectief van binnenuit... m=meubels.
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Etic
Etic=perspectief van buitenaf... t=tuin.
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Many instruments are adopted from the English language, which is a risk for ethnocentrism. o With many comparing and looking for similarities between cultures, important details are quickly skipped, creating a blind spot
Twijfelpunten etic approach: - Oorspronkelijke Engelse instrumenten leiden tot etnocentrisme (=minder kijken naar andere culturen). - Vergelijken en overeenkomsten zoeken leidt tot belangrijke details overslaan (=blinde vlek).
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Participants were then assessed on whether they looked more at the individual or the group using a task in which a number of fish were shown and participants had to indicate why one fish swam in front. Participants who had received the Chinese primes primarily indicated that the fish was being chased by the group (a situational explanation). Participants who had received the USA primes primarily indicated that the fish was the leader of the group (a dispositional statement). The control group, in which no primes were used, was in between. Frame switching not only happens here, but also more generally in cognition, emotions and behavio
Morris & Peng; Aquarium onderzoek: - Chinese prikkel: situationele verklaring=vis achtervolgd. - Amerikaanse prikkel: dispositionele verklaring= vis leider. - Controle groep: tussenin...
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dispositions
Dispositions=persoonlijke staat..
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prejudice
Prejudice=vooroordelen.
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cultural identity, racial identity, ethnic identity and national identity.
Culturele identiteit: biologisch (?) construct. Ras identiteit: sociaal construct. Ethische identiteit: sociaal construct. Nationale identiteit: biologisch construct.
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social categories
Collective=cultureel/ groepsniveau.
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The state self-esteem scale contains three types of self-esteem, namely performance, social and appearance
Zelfverzekerdheid schaal: - Prestaties. - (sociaal) gedrag. - Uiterlijk.
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The studies document these differences without looking at whether the self actually mediates the outcomes. In addition, the concepts are used to characterize cultures, but individual-level data are needed to make statements about causality and mediation. Furthermore, self-construal is used as a dichotomous concept, whereas it can also be viewed as dimensional.
Twijfelpunten omtrent onderzoek 20-statments test: - Verschillen documenteren zonder uitkomst te checken. - - Concepten inzetten om cultuur te labelen, zonder op individueel niveau te checken. - Zelfconstructie gebruiken als dichotoom, in plaats van dit zien als iets dimensioneels.
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university.pressbooks.pub university.pressbooks.pub
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toolbar
took out the paragraph with they keyboard shortcuts. they don't work on Mac.
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edisciplinas.usp.br edisciplinas.usp.br
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deprivation of resources neededfor physical survival, like clean water, food (e.g., buffalo), clothing, shelteror medical services. This definition also includes actions targeting womenspecifically, like involuntary sterilization, forced abortion, prohibition ofmarriage, and long-term separation of men and women, all of whichthreaten the ability to produce future generations
direct UN def violation
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Crazy Horseand Spotted Tail came to represent two traditions of Indigenous resistance;one would follow a path of armed struggle, the other the path of diplomacy.
Crazy Horse and Spotted Tail came to represent two traditions of Indigenous resistance; one would follow a path of armed struggle, the other the path of diplomacy.
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“Wasicu” became synonymous withthe United States, a nation that behaved as if it had no relatives.
very eye catching statement
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General WilliamS. Harney
horrible person
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digitalcommons.usf.edu digitalcommons.usf.edu
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Group A: Low placement score, developmental math not required, enhanced section● Group B: High placement score, developmental math not required, enhanced section● Group C: Low placement score, developmental math required, enhanced section● Group D: Low placement score, developmental math required, non-enhanced section
I assume that the "not required" means it was waived.
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athematics.In 2017–2018, the developmental mathematics instructional requirement as aformal prerequisite was waived for a subset of student
OK WHOA .... so far, far from random selection. So the whole idea that "they did better" mgiht have been because htey were in this cohort.
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In other words, the student populationnecessary to address RQ1 exists only for QL1 and CA
Welp, ql1 was the more "mathy' version.
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MSU also regularly offers several summer experiences for matriculatingstudents
yup!!!
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Oneformer option was a formal, one-semester developmental mathematics courselargely offered online.
I bet it was procedural.
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he authors were not involvedin the design of the enhanced course sections.
Interesting. Very interensting. Would they have done differently?
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recitation
(what's recitation?)
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. All of this is to saythat many of the students whom we work with and discuss in this paper arrive withcumulative disadvantages that no special program can remove altogether.
**RIGHT **
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Before transitioning to specific details about embedded remediation at MSU,we believe it is important to note that neither the pathways nor the embeddedremediation approach inherently leads to socially just outcomes. If we substitutethe word pathways for tracks, for example, this point becomes salient.
Amen.
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Understandably, the corequisite model has gained traction forits alluring removal of the necessity of multiple semesters for students
More interesting language but boy do I appreciate the "alluring." And hey, it's "successful"! THe CA law is like the IL law.
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he approach benefits students’ affect in relation to mathematics,timeline to graduation, and required mathematical skills
... so it improves student attitude....
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This abridged version of developmental mathematicsincludes only the content that students will need to be successful in latercoursework, jettisoning other topics (e.g., polynomial long division) that tend tohinder student success and that bear little import for students’ future coursework orcareers
Think of the lots and lots of meetings discussing this :P Note it doesn't say "just use a calculator to figure out percents."
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reatingalternatives is challenging,
(yup, challenging.... )
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gained notoriety
lol not loaded language or anything
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Students encountering the university mathematicsgraduation requirement given their resources—in some cases, low mathematicsplacement scores and room for improvement in their mathematical knowledge andskills—have a similar problem of access
"room for improvement..." yes.
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drive.google.com drive.google.com
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Beautiful vision.
(Having a human voice read the words would be even more compelling.)
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www.medrxiv.org www.medrxiv.org
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Author response:
The following is the authors’ response to the current reviews.
Public Reviews:
Reviewer #2 (Public review):
Weaknesses:
The authors have clarified that the first features available for each patient have been used. However, they have not shown that these features did not occur before the time of post-stroke epilepsy. Explicit clarification of this should be performed.
The data utilized in our analysis were collected during the first examination or test conducted after the patients' admission. We specifically excluded any patients with a history of epilepsy, ensuring that all cases of epilepsy identified in our study occurred after admission. Therefore, the features we analyzed were collected after the patients' admission but prior to the onset of post-stroke epilepsy.
Reviewer #3 (Public review):
Weaknesses:
The writing of the article may be significantly improved.
Although the external validation is appreciated, cross-validation to check robustness of the models would also be welcome.
Thank you for your helpful advice. Performing n-fold cross-validation is a crucial step to ensure the reliability and robustness of the reported results, especially when dealing with the datasets which don't have sufficient quantity. We revised our code and did a 5 fold cross-validation version ,it didn’t have much promote(because our model has reach the auc of 0.99).Considering that we have sufficient quantity of more than 20000 records, we think split the dataset by 7:3 and train the model is enough for us. We have uploaded the code of 5 fold cross-validation version and ploted the 5 fold test roc on GitHub at https://github.com/conanan/lasso-ml/lasso_ml_cross_validation.ipynb as an external resource. We trained the 5 fold average model and ploted the 5 fold test roc curves, the results show some improvement, but it is not substantial because the best model are still tree models in the end.
External validation results may be biased/overoptimistic, since the authors informed that "The external validation cohort focused more on collecting positive cases 80 to examine the model's ability to identify positive samples", which may result in overoptimistic PPV and Sensitivity estimations. The specificity for the external validation set has not been disclosed.
Thank you for your valuable feedback regarding the external validation results. We appreciate your concerns about potential bias and overoptimism in our estimations of positive predictive value (PPV) and sensitivity.
To clarify, we have uploaded the code for external validation on GitHub at https://github.com/conanan/lasso-ml. The results indicate that the PPV is 0.95 and the specificity is 0.98.
While we focused on collecting more positive cases due to their lower occurrence rate, this approach allows us to better evaluate the model's ability to predict positive samples, which is crucial in clinical settings. We believe that emphasizing positive cases enhances the model's utility for practical applications(So a little overoptimism is acceptable ).
The following is the authors’ response to the original reviews.
Public Reviews:
Reviewer #1 (Public Review):
Weaknesses 1:
The methodology needs further consideration. The Discussion needs extensive rewriting.
Thanks for your advice, we have revised the Discussion
Reviewer #2 (Public Review):
Weaknesses 2:
There are many typos and unclear statements throughout the paper.
There are some issues with SHAP interpretation. SHAP in its default form, does not provide robust statistical guarantees of effect size. There is a claim that "SHAP analysis showed that white blood cell count had the greatest impact among the routine blood test parameters". This is a difficult claim to make.
Thank you for your suggestion that the SHAP analysis is really just a means of interpreting the model. In our research, we compared the SHAP analysis with traditional statistical methods, such as regression analysis. We found the SHAP results to be consistent with the statistical results from the regression for variables like white blood cell count (see Table 1). This alignment leads us to believe the SHAP analysis is providing reliable insights in this context
The Data Collection section is very poorly written, and the methodology is not clear.
Thanks for your advice, we have revised the Data Collection section.
There is no information about hyperparameter selection for models or whether a hyperparameter search was performed. Given this, it is difficult to conclude whether one machine learning model performs better than others on this task.
Thank you for the advices of performing hyperparameter. We used the package of sklearn, xgboost, lightgbm of python 3.10 to construct the model and didn’t change the default settings before. It is not proper and may lead to less certain conclusions. Now we carry out grid search to select and optimize hyperparameters and they make the model better. The best model is still RF.
The inclusion and exclusion criteria are unclear - how many patients were excluded and for what reasons?
The procedure of selection is in figure1. Total there are 42079 records from the stroke database, 24733 patients were diagnosed as ischemic stroke or lacular stoke with new onset. Then we excluded hemorrage stroke(4565),history of stroke(2154), TIA(3570), unclear cause stroke(561) and records who missed important data(6496). Then we excluded patients whose seizure might be attributed to other potential causes (brain tumor, intracranial vascular malformation, traumatic brain injury,etc)(865). Then we exclude patient who had a seizure history(152) or died in hospital (1444). Then we excluded patients who were lost in follow-up (had no outpatient records and can’t contact by phone )or died within 3 months of the stroke incident(813). Finally 21459 cases are involved in this research.
There is no sensitivity analysis of the SMOTE methodology: How many synthetic data points were created, and how does the number of synthetic data points affect classification accuracy?
Thanks for your remind, we have accept these advice and change the SMOTE to SMOTEENN (Synthetic Minority Over-sampling Technique combined with Edited Nearest Neighbors) technique to resample an imbalanced dataset for machine learning. The code is
smoteenn = SMOTEENN(samplingstrategy='auto', randomstate=42)
the SMOTEENN class comes from the imblearn library. The samplingstrategy='auto' parameter tells the algorithm to automatically determine the appropriate sampling strategy based on the class distribution. The randomstate=42 parameter sets a seed for the random number generator, ensuring reproducibility of the results.
Did the authors achieve their aims? Do the results support their conclusions?
Yes, we have achieve some of the aims of predicting PSE while still leave some problem.
The paper does not clarify the features' temporal origins. If some features were not recorded on admission to the hospital but were recorded after PSE occurred, there would be temporal leakage.
The data used in our analysis is from the first examination or test conducted after the patients' admission, retrieved from a PostgreSQL database. First, we extracted the initial admission date for patients admitted due to stroke. Then, we identified the nearest subsequent examination data for each of those patients.
The sql code like follows:
SELECT TO_DATE(condition_start_date, 'DD-MM-YYYY') AS DATE
FROM diagnosis
WHERE person_id ={} and (condition_name like '%梗死%' or condition_name like '%梗塞%') and(condition_name like '%脑%'or condition_name like '%腔隙%'))
order by DATE limit 1
The authors claim that their models can predict PSE. To believe this claim, seeing more information on out-of-distribution generalisation performance would be helpful. There is limited reporting on the external validation cohort relative to the reporting on train and test data.
Thank you for the advice. The external validation is certainly very important, but there have been some difficulties in reaching a perfect solution. We have tried using open-source databases like the MIMIC database, but the data there does not fit our needs as closely as the records from our own hospital. The MIMIC database lacks some of the key features we require, and also lacks the detailed patient follow-up information that is crucial for our analysis. Given these limitations, we have decided to collect newer records from the same hospitals here in Chongqing. We believe this will allow us to build a more comprehensive dataset to support robust external validation. While it may not be a perfect solution, gathering this additional data from our local healthcare system is a pragmatic step forward. Looking ahead, we plan to continue expanding this Chongqing-based dataset and report on the results of the greater external validation in the future. We are committed to overcoming the challenges around data availability to strengthen the validity and generalizability of our research findings.
For greater certainty on all reported results, it would be most appropriate to perform n-fold cross-validation, and report mean scores and confidence intervals across the cross-validation splits
Thank you for your helpful advice. Performing n-fold cross-validation is a crucial step to ensure the reliability and robustness of the reported results, especially when dealing with the datasets which don't have sufficient quantity. While we have sufficient quantity of more than 20000 records, so we think split the dataset by 7:3 and train the model is enough for us. We revised our code and did a 5 fold cross-validation version ,it had little promote(because our model has reach the auc of 0.99), we may use this great technique in our next study if there is not enough cases.
Additional context that might help readers
The authors show force plots and decision plots from SHAP values. These plots are non-trivial to interpret, and the authors should include an explanation of how to interpret them.
Thank you for your helpful advice. It is a great improve for our draft, we have added the explanation that we use the force plot of the first person to show the influence of different features of the first person, we can see that long APTT time contribute best to PSE, then the AST level and others, the NIHSS score may be low and contribute opposite to the final result. Then the decision plot is a collection of model decisions that show how complex models arrive at their predictions
Reviewer #3 (Public Review):
Weaknesses3:
There are issues with the readability of the paper. Many abbreviations are not introduced properly and sometimes are written inconsistently. A lot of relevant references are omitted. The methodological descriptions are extremely brief and, sometimes, incomplete.
Thanks for your advice, we have revised these flaws.
The dataset is not disclosed, and neither is the code (although the code is made available upon request). For the sake of reproducibility, unless any bioethical concerns impede it, it would be good to have these data disclosed.
Thank you for your recommendations. We have made the code available on GitHub at https://github.com/conanan/lasso-ml. While the data is private and belongs to the hospital. Access can be requested by contacting the corresponding author to apply from the hospitals and specifying the purpose of inquiry.
Although the external validation is appreciated, cross-validation to check the robustness of the models would also be welcome.
Thank you for your valuable advice. Performing n-fold cross-validation is crucial for ensuring the reliability and robustness of results, especially with limited datasets. However, since we have over 20,000 records, we believe that a 70:30 split for training and testing is sufficient.
We revised our code and implemented 5-fold cross-validation, which provided minimal improvement, as our model has already achieved an AUC of 0.99. We plan to use this technique in future studies if we encounter fewer cases.
Recommendations for the authors:
Reviewer #1 (Recommendations For The Authors):
My comments include two parts:
(1) Methodology<br /> a-This study was based on multiple clinical indicators to construct a model for predicting the occurrence of PSE. It involved various multi-class indicators such as the affected cortical regions, locations of vascular occlusion, NIHSS scores, etc. Only using the SHAP index to explain the impact of multi-class variables on the dependent variable seems slightly insufficient. It might be worth considering the use of dummy variables to improve the model's accuracy.
Thank you for the detailed feedback on the study methodology. The SHAP analysis is really just a means of interpreting the model, which we compared with the combination of SHAP and traditional statistics, so we think SHAP analysis is reliable in this research. We have used the dummy variables, expecially when dealing with the affected cortical regions, locations of vascular occlusion, for example if frontal region is involved the variable is 1. But they have less impact in the machine learning model
b-The study used Lasso regression to select 20 features to build the model. How was the optimal number of 20 features determined?
Lasso regression is a commonly used feature screening method. Since we extract information from the database and try to include as many features as possible, the cross-verification curve of lasso regression includes 78 features best, but it will lead to too complex model. We select 10,15,20,25,30 features for modeling according to the experiment. When 20 features are found, the model parameters are good and relatively concise. Improve the number of features contribute little to the model effect, decrease the number of features influence the concise of model ,for example the auc of the model with 15 features will drop under 0.95. So we finally select 20 features.
c-The study indicated that the incidence rate of PSE in the enrolled patients is 4.3%, showing a highly imbalanced dataset. If singly using the SMOTE method for oversampling, could this lead to overfitting?
Thanks for your remind, singly using the SMOTE method for oversampling is inproper. Now we have find this improvement and change the SMOTE to SMOTEENN (Synthetic Minority Over-sampling Technique combined with Edited Nearest Neighbors) technique to resample an imbalanced dataset for machine learning. First, oversampling with SMOTE and then undersampling with ENN to remove possible noise and duplicate samples. The code is
smoteenn = SMOTEENN(sampling_strategy='auto', random_state=42)
the SMOTEENN class comes from the imblearn library. The sampling_strategy='auto' parameter tells the algorithm to automatically determine the appropriate sampling strategy based on the class distribution. The random_state=42 parameter sets a seed for the random number generator, ensuring reproducibility of the results.
(2) Clinical aspects:
Line 8, history of ischemic stroke, this is misexpression, could be: diagnosis of ischemic stroke.
Line 8, several hospitals, should be more exact; how many?
Line 74 indicates that the data are from a single centre, this should be clarified.
Line 4 data collection: The criteria read unclear; please clarify further.
Thanks for your remind, we have revised the draft and correct these errors.
Line 110, lab parameters: Why is there no blood glucose?
Because many patients' blood sugar fluctuates greatly and is easily affected by drugs or diet, we finally consider HBA1c as a reference index by asking experts which is more stable.
Line 295, The author indicated that data lost; this should be clarified in the results part, and further, the treatment of missing data should be clarified in the method part.
Thanks for your remind, we have revised the draft and correct these errors.
I hope to see a table of the cohort's baseline characters. The discussion needs extensive rewriting; the author seems to be swinging from the stoke outcome and the seizure, sometimes losing the target.
Figure1 is the procedure of the selection of patients. Table1 contains the cohort's baseline characters
For the swinging from the stoke outcome and the seizure, that is because there are few articles on predicting epilepsy directly by relevant indicators, while there are more articles on prognosis. So we can only take epilepsy as an important factor in prognosis and comprehensively discuss it, or we can't find enough articles and discuss them
Reviewer #2 (Recommendations For The Authors):
There are typos and examples of text that are not clear, including:
"About the nihss score, the higher the nihss score, the more likely to be PSE, nihss score has a third effect just below white blood cell count and D-dimer."
"and only 8 people made incorrect predictions, demonstratijmng a good predictive ability of the model."
"female were prone to PSE"
" Waafi's research"
"One-heat' (should be one-hot)
Thanks for your remind, we have revised the draft and correct these errors.
The Data Collection section is poorly written, and the methodology is not clear. It would be much more appropriate to include a table of all features used and an explanation of what these features involve. It would also be useful to see the mean values of these features to assess whether the feature values are reasonable for the dataset.
Thanks for your remind. All data are from the first examination or test after admission, presented through the postgresql database . First we extract the first date of the patients who was admitted by stroke ,then we extract informations from the nearest examination from the admission. We extract by the SQL code by computer instead of others who may extract data by manual so we get as much data as possible other than only get the features which was reported before .The table of all features used and their mean±std is in table1.
The paper does not clarify the features' temporal origins. If some features were not recorded on admission to the hospital but were recorded after PSE occurred, there would be temporal leakage. I would need this clarified before believing the authors achieved their claims of building a predictive model.
All relevant index results were from the first examination after admission, and the mean standard deviation was listed in the statistical analysis section in table1.
The authors claim that their models can predict PSE. To believe this claim, seeing more information on out-of-distribution generalisation performance would be helpful. There is limited reporting on the external validation cohort relative to the reporting on train and test data.
Thank you for the advice, the external validation is very important but there are some difficulties to reach a perfect one. We have tried some of the open source database like the mimic database ,but these data don't fit our request because they don't have as much features as our hospital and lack of follow-up of the relevant patients. In the end we collected the newer records in the same hospitals in Chongqing and we will collect more and report a greater external validation in the future.
For greater certainty on all reported results, It would be most appropriate to perform n-fold cross-validation, and report mean scores and confidence intervals across the cross-validation splits.
Thank you for your helpful advice. Performing n-fold cross-validation is a crucial step to ensure the reliability and robustness of the reported results, especially when dealing with the datasets which don't have sufficient quantity. While we have sufficient quantity of more than 20000 records, so we think split the dataset by 7:3 and train the model is enough for us. We revised our code and did a 5 fold cross-validation version ,it had little promote, we will use this great technique in our next study.
The authors show force plots and decision plots from SHAP values. These plots are non-trivial to interpret, and the authors should include an explanation of how to interpret them.
It is a great improve for our draft, we have added the explanation we use the force plot of the first person to show the influence of different features of the first person, we can see that long APTT time contribute best to PSE, then the AST level and others, the NIHSS score may be low and contribute lower to the final result. Then the decision plot is a collection of model decisions that show how complex models arrive at their predictions
Reviewer #3 (Recommendations For The Authors):
Abbreviations should not be defined in the abstract )or only in the abstract).
Please explicit what are the purposes of the study you are referring to in "Currently, most studies utilize clinical data to establish statistical models, survival analysis and cox regression."
Authors affirm: "there is still a relative scarcity of research 49 on PSE prediction, with most studies focusing on the analysis of specific or certain risk factors ." This statement is especially curious since the current study uses risk factors as predictors.
It is not clear to me what the authors mean by "No study has proposed or established a more comprehensive and scientifically accurate prediction model." The authors do not summarize the statistical parameters of previously reported model, or other relevant data to assess coverage or validity (maybe including a Table summarizing such information would be appropriate. In any case, I would try to omit statements that imply, to some extent, discrediting previous studies without sufficient foundation.
"antiepileptic drugs" is an outdated name. Please use "antiseizure medications"
Thanks for your remind, we have revised the draft and correct these errors.
The authors say regarding missing data that they "filled the data of the remaining indicators with missing values of more than 1000 cases by random forest algorithm". Please clarify what you mean by "of more than 1000 cases." Also, provide details on the RF model used to fill in missing data.
Thanks for your remind. "of more than 1000 cases" was a wrong sentence and we have corrected it. Here is the procedure, first we counted the values of all laboratory indicators for the first time after stroke admission( everyone who was admitted because of stroke would perform blood routine , liver and kidney function and so on), excluded indicators with missing values of more than 10%, and filled the data of the remaining indicators with missing values by random forest algorithm using the default parameter. First, we go through all the features, starting with the one with the least missing (since the least accurate information is needed to fill in the feature with the least missing). When filling in a feature, replace the missing value of the other feature with 0. Each time a regression prediction is completed, the predicted value is placed in the original feature matrix and the next feature is filled in. After going through all the features, the data filling is complete.
Please specify what do you mean by negative group and positive group, Avoid tacit assumptions.
Thanks for your remind, we have revised the draft and correct these errors.
Please provide more details (and references) on the smote oversampling method. Indicate any relevant parameters/hyperparameters.
Thanks for your remind, we have accept these advice and change the SMOTE to SMOTEENN (Synthetic Minority Over-sampling Technique combined with Edited Nearest Neighbors) technique to resample an imbalanced dataset for machine learning. The code is
smoteenn = SMOTEENN(sampling_strategy='auto', random_state=42)
the SMOTEENN class comes from the imblearn library. The sampling_strategy='auto' parameter tells the algorithm to automatically determine the appropriate sampling strategy based on the class distribution. The random_state=42 parameter sets a seed for the random number generator, ensuring reproducibility of the results.
The methodology is presented in an extremely succinct and non-organic manner (e.g., (Model building) Select the 20 features with the largest absolute value of LASSO." Please try to improve the narrative.
Lasso regression is a commonly used feature screening method. Since we extract information from the database and try to include as many features as possible, the cross-verification curve of lasso regression includes 78 features best, but it will lead to too complex model. We select 10,15,20,25,30 features for modeling according to the experiment. When 20 features are found, the model parameters are good and relatively concise. Improve the number of features contribute little to the model effect, decrease the number of features influence the concise of model ,for example the auc of the model with 15 features will drop under 0.95. So we finally select 20 features.
Many passages of the text need references. For example, those that refer to Levene test, Welch's t-test, Brier score, Youden index, and many others (e.g., NIHSS score). Please revise carefully.
Thanks for your remind, we have revised the draft and correct these errors.
"Statistical details of the clinical characteristics of the patients are provided in the table." Which table? Number?
Thanks for your remind, we have revised the draft and correct these errors, it is in table1.
Many abbreviations are not properly presented and defined in the text, e.g., wbc count, hba1c, crp, tg, ast, alt, bilirubin, bua, aptt, tt, d_dimer, ck. Whereas I can guess the meaning, do not assume everyone will. Avoid assumptions.
ROC is sometimes written "ROC" and others, "roc." The same happens for PPV/ppv, and many other words (SMOTE; NIHSS score, etc.).
Please rephrase "ppv value of random forest is the highest, reaching 0.977, which is more accurate for the identification of positive patients(the most important function of our models).". PPV always refer to positive predictions that are corroborated, so the sentences seem redundant.
Thanks for your remind, we have revised the draft and correct these errors.
What do you mean by "Complex algorithms". Please try to be as explicit as possible. The text looks rather cryptic or vague in many passages.
Thanks for your remind, "Complex algorithms" is corrected by machine learning.
The text needs a thorough English language-focused revision, since the sense of some sentences is really misleading. For instance "only 8 people made incorrect predictions,". I guess the authors try to say that the best algorithm only mispredicted 8 cases since no people are making predictions here. Also, regarding that quote... Are the authors still speaking of the results of the random forest model, which was said to be one of the best performances?
Thanks for your remind, we have revised the draft and correct these errors.
The authors say that they used, as predictors "comprehensive clinical data, imaging data, laboratory test data, and other data from stroke patients". However, the total pool of predictors is not clear to me at this point. Please make it explicit and avoid abbreviations.
Thanks for your remind, we have revised the draft and correct these errors.
Although the authors say that their code is available upon request, I think it would be better to have it published in an appropriate repository.
Thanks for your remind, we showed our code at https://github.com/conanan/lasso-ml.
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blessings of liberty
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eLife Assessment
This study aims to analyse the effect of polymorphism on meiotic recombination in subspecies of Saccharomyces. The detection of reciprocal and non-reciprocal events is based on sequencing the haploid products of meiosis, and frequencies are compared between strains having introgressed genomic segments and strains lacking such segments. Unfortunately, the method used are inadequate for quantifying the non-reciprocal events.
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Reviewer #1 (Public review):
Summary:
The authors explored how the presence of interspecific introgressions in the genome affects the recombination landscape. This research aims to shed light on the genetic phenomena influencing the evolution of introgressed regions. However, it is important to note that the study is based on examining only one generation, which limits the scope for making broad evolutionary conclusions. In this study, yeast hybrids with large introgressions (ranging from several to several dozen percent of the chromosome length) from another yeast species were crossed. The products of meiosis were then isolated and sequenced to examine the genome-wide distribution of both crossovers (COs) and noncrossovers (NCOs). The authors found a significant reduction in the frequency of COs within the introgressed regions, which is a phenomenon well-documented in various systems. They also report that introgressed regions exhibit an increased frequency of NCOs. Unfortunately, this conclusion seems flawed, as there is no accurate method for correcting the detection level of NCOs when the compared regions (introgressed and non-introgressed) differ drastically in SNP density. The authors further confirmed that introgressions significantly limit the local shuffling of genetic information, and while NCOs contribute slightly to this shuffling, they do not compensate for the loss of CO recombination. This is widely known fact.
In summary, the study makes a limited contribution to the understanding of how polymorphism impacts meiotic recombination. The conclusion regarding the increase in NCO frequency in polymorphic regions is likely incorrect.
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Reviewer #3 (Public review):
When members of two related but diverged species mate, the resulting hybrids can produce offspring where parts of one species' genome replace those of the other. These "introgressions" often create regions with a much greater density of sequence differences than are normally found between members of the same species. Previous studies have shown that increased sequence differences, when heterozygous, can reduce recombination during meiosis specifically in the region of increased difference. However, most of these studies have focused on crossover recombination, and have not measured noncrossovers. The current study uses a pair of Saccharomyces uvarum crosses: one between two natural isolates that, while exhibiting some divergence, do not contain introgressions; the other is between two fermentation strains that,<br /> when combined, are heterozygous for 9 large regions of introgression that have much greater divergence than the rest of the genome. The authors wished to determine if introgressions differently affected crossovers and noncrossovers, and, if so, what impact that would have on the gene shuffling that occurs during<br /> meiosis.
While both crossovers and noncrossovers were measured, assessing the true impact of increased heterology (inherent in heterozygous introgressions) is complicated by the fact that the increased marker density in heterozygous introgressions also increases the ability to detect noncrossovers. The authors now use a revised correction aimed at compensating for this difference, and based on that correction, conclude that, while as expected crossovers are decreased by increased sequence heterology, noncrossovers neither increase nor decrease substantially. They then show that genetic shuffling overall is substantially reduced in regions of heterozygous introgression, which is not surprising given that one type of event is reduced and the other remains at similar levels. However, the correction currently used remains poorly justified, tests of its validity are not presented. Thus, the only possibly novel conclusion, that noncrossovers are less affected by heterology than crossovers, remains to be adequately tested.
In conclusion, of the three main conclusions as stated in the abstract, one (that crossovers go down) has been shown in many systems, one (that noncrossovers increase) is wrong, and the third (that allele shuffling is reduced) is obvious. Given this, the impact of this work on the field will be minimal at best, and negative to the extent that readers are led astray.
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Author response:
The following is the authors’ response to the original reviews.
Public Reviews:
Reviewer #1 (Public Review):
Summary:
The authors investigated how the presence of interspecific introgressions in the genome affects the recombination landscape. This research was intended to inform about genetic phenomena influencing the evolution of introgressed regions, although it should be noted that the research itself is based on examining only one generation, which limits the possibility of drawing far-reaching evolutionary conclusions. In this work, yeast hybrids with large (from several to several dozen percent of the chromosome length) introgressions from another yeast species were crossed. Then, the products of meiosis were isolated and sequenced, and on this basis, the genome-wide distribution of both crossovers (COs) and noncrossovers (NCOs) was examined. Carrying out the analysis at different levels of resolution, it was found that in the regions of introduction, there is a very significant reduction in the frequency of COs and a simultaneous increase in the frequency of NCOs. Moreover, it was confirmed that introgressions significantly limit the local shuffling of genetic information, and NCOs are only able to slightly contribute to the shuffling, thus they do not compensate for the loss of CO recombination.
Strengths:
- Previously, experiments examining the impact of SNP polymorphism on meiotic recombination were conducted either on the scale of single hotspots or the entire hybrid genome, but the impact of large introgressed regions from another species was not examined. Therefore, the strength of this work is its interesting research setup, which allows for providing data from a different perspective.
- Good quality genome-wide data on the distribution of CO and NCO were obtained, which could be related to local changes in the level of polymorphism.
Weaknesses:
(1) The research is based on examining only one generation, which limits the possibility of drawing far-reaching evolutionary conclusions. Moreover, meiosis is stimulated in hybrids in which introgressions occur in a heterozygous state, which is a very unlikely situation in nature. Therefore, I see the main value of the work in providing information on the CO/NCO decision in regions with high sequence diversification, but not in the context of evolution.
While we are indeed only examining recombination in a single generation, we respectfully disagree that our results aren't relevant to evolutionary processes. The broad goals of our study are to compare recombination landscapes between closely related strains, and we highlight dramatic differences between recombination landscapes. These results add to a body of literature that seeks to understand the existence of variation in traits like recombination rate, and how recombination rate can evolve between populations and species. We show here that the presence of introgression can contribute to changes in recombination rate measured in different individuals or populations, which has not been previously appreciated. We furthermore show that introgression can reduce shuffling between alleles on a chromosome, which is recognized as one of the most important determinants for the existence and persistence of sexual reproduction across all organisms. As we describe in our introduction and conclusion, we see our experimental exploration of the impacts of introgression on the recombination landscape as complementary to studies inferring recombination and introgression from population sequencing data and simulations. There are benefits and challenges to each approach, but both can help us better understand these processes. In regards to the utility of exploring heterozygous introgression, we point out that introgression is often found in a heterozygous state (including in modern humans with Neanderthal and/or Denisovan ancestry). Introgression will always be heterozygous immediately after hybridization, and depending on the frequency of gene flow into the population, the level of inbreeding, selection against introgression, etc., introgression will typically be found as heterozygous.
- The work requires greater care in preparing informative figures and, more importantly, re-analysis of some of the data (see comments below).
More specific comments:
(1) The authors themselves admit that the detection of NCO, due to the short size of conversion tracts, depends on the density of SNPs in a given region. Consequently, more NCOs will be detected in introgressed regions with a high density of polymorphisms compared to the rest of the genome. To investigate what impact this has on the analysis, the authors should demonstrate that the efficiency of detecting NCOs in introgressed regions is not significantly higher than the efficiency of detecting NCOs in the rest of the genome. If it turns out that this impact is significant, analyses should be presented proving that it does not entirely explain the increase in the frequency of NCOs in introgressed regions.
We conducted a deeper exploration of the effect of marker resolution on NCO detection by randomly removing different proportions of markers from introgressed regions of the fermentation cross in order to simulate different marker resolutions from non-introgressed regions. We chose proportions of markers that would simulate different quantiles of the resolution of non-introgressed regions and repeated our standard pipeline in order to compare our NCO detection at the chosen marker densities. More details of this analysis have been added to the manuscript (lines 188-199, 525-538). We confirmed the effect of marker resolution on NCO detection (as reported in the updated manuscript and new supplementary figures S2-S10, new Table S10) and decided to repeat our analyses on the original data with a more stringent correction. For this we chose our observed average tract size for NCOs in introgressed regions (550bp), which leads to a far more conservative estimate of NCO counts (As seen in the updated Figure 2 and Table 2). This better accounts for the increased resolution in introgressed regions, and while it's possible to be more stringent with our corrections, we believe that further stringency would be unreasonable. We also see promising signs that the correction is sufficient when counting our CO and NCO events in both crosses, as described in our response to comment 39 (response to reviewer #3).
(2) CO and NCO analyses performed separately for individual regions rarely show statistical significance (Figures 3 and 4). I think that the authors, after dividing the introgressed regions into non-overlapping windows of 100 bp (I suggest also trying 200 bp, 500 bp, and 1kb windows), should combine the data for all regions and perform correlations to SNP density in each window for the whole set of data. Such an analysis has a greater chance of demonstrating statistically significant relationships. This could replace the analysis presented in Figure 3 (which can be moved to Supplement). Moreover, the analysis should also take into account indels.
We're uncertain of what is being requested here. If the comment refers to the effect of marker density on NCO detection, we hope the response to comment 2 will help resolve this comment as well. Otherwise, we ask for some clarification so that we may correct or revise as appropriate.
(3) In Arabidopsis, it has been shown that crossover is stimulated in heterozygous regions that are adjacent to homozygous regions on the same chromosome (http://dx.doi.org/10.7554/eLife.03708.001, https://doi.org/10.1038/s41467-022-35722-3).
This effect applies only to class I crossovers, and is reversed for class II crossovers (https://doi.org/10.15252/embj.2020104858, https://doi.org/10.1038/s41467-023-42511-z). This research system is very similar to the system used by the authors, although it likely differs in the level of DNA sequence divergence. The authors could discuss their work in this context.
We thank the reviewer for sharing these references. We have added a discussion of our work in the context of these findings in the Discussion, lines 367-376.
Reviewer #2 (Public Review):
Summary:
Schwartzkopf et al characterized the meiotic recombination impact of highly heterozygous introgressed regions within the budding yeast Saccharomyces uvarum, a close relative of the canonical model Saccharomyces cerevisiae. To do so, they took advantage of the naturally occurring Saccharomyces bayanus introgressions specifically within fermentation isolates of S. uvarum and compared their behavior to the syntenic regions of a cross between natural isolates that do not contain such introgressions. Analysis of crossover (CO) and noncrossover (NCO) recombination events shows both a depletion in CO frequency within highly heterozygous introgressed regions and an increase in NCO frequency. These results strongly support the hypothesis that DNA sequence polymorphism inhibits CO formation, and has no or much weaker effects on NCO formation. Eventually, the authors show that the presence of introgressions negatively impacts "r", the parameter that reflects the probability that a randomly chosen pair of loci shuffles their alleles in a gamete.
The authors chose a sound experimental setup that allowed them to directly compare recombination properties of orthologous syntenic regions in an otherwise intra-specific genetic background. The way the analyses have been performed looks right, although this reviewer is unable to judge the relevance of the statistical tests used. Eventually, most of their results which are elegant and of interest to the community are present in Figure 2.
Strengths:
Analysis of crossover (CO) and noncrossover (NCO) recombination events is compelling in showing both a depletion in CO frequency within highly heterozygous introgressed regions and an increase in NCO frequency.
Weaknesses:
The main weaknesses refer to a few text issues and a lack of discussion about the mechanistic implications of the present findings.
- Introduction
(1) The introduction is rather long. | I suggest specifically referring to "meiotic" recombination (line 71) and to "meiotic" DSBs (line 73) since recombination can occur outside of meiosis (ie somatic cells).
We agree and have condensed the introduction to be more focused. We also made the suggested edits to include “meiotic” when referring to recombination and DSBs.
(2) From lines 79 to 87: the description of recombination is unnecessarily complex and confusing. I suggest the authors simply remind that DSB repair through homologous recombination is inherently associated with a gene conversion tract (primarily as a result of the repair of heteroduplex DNA by the mismatch repair (MMR) machinery) that can be associated or not to a crossover. The former recombination product is a crossover (CO), the latter product is a noncrossover (NCO) or gene conversion. Limited markers may prevent the detection of gene conversions, which erase NCO but do not affect CO detection.
We changed the language in this section to reflect the reviewer’s suggestions.
(3) In addition, "resolution" in the recombination field refers to the processing of a double Holliday junction containing intermediates by structure-specific nucleases. To avoid any confusion, I suggest avoiding using "resolution" and simply sticking with "DSB repair" all along the text.
We made the suggested correction throughout the paper.
(4) Note that there are several studies about S. cerevisiae meiotic recombination landscapes using different hybrids that show different CO counts. In the introduction, the authors refer to Mancera et al 2008, a reference paper in the field. In this paper, the hybrid used showed ca. 90 CO per meiosis, while their reference to Liu et al 2018 in Figure 2 shows less than 80 COs per meiosis for S. cerevisiae. This shows that it is not easy to come up with a definitive CO count per meiosis in a given species. This needs to be taken into account for the result section line 315-321.
This is an excellent point. We added this context in the results (lines 180-187).
(5) In line 104, the authors refer to S. paradoxus and mention that its recombination rate is significantly different from that of S. cerevisiae. This is inaccurate since this paper claims that the CO landscape is even more conserved than the DSB landscape between these two species, and they even identify a strong role played by the subtelomeric regions. So, the discussion about this paper cannot stand as it is.
We agree with the reviewer's point. We also found that the entire paragraph was unnecessary, so it and the sentence in question have been removed.
(6) Line 150, when the authors refer to the anti-recombinogenic activity of the MMR, I suggest referring to the published work from Martini et al 2011 rather than the not-yet-published work from Copper et al 2021, or both, if needed.
Added the suggested citation.
Results
(7) The clear depletion in CO and the concomitant increase in NCO within the introgressed regions strongly suggest that DNA sequence polymorphism triggers CO inhibition but does not affect NCO or to a much lower extent. Because most CO likely arises from the ZMM pathway (CO interference pathway mainly relying on Zip1, 2, 3, 4, Spo16, Msh4, 5, and Mer3) in S. uvarum as in S. cerevisiae, and because the effect of sequence polymorphism is likely mediated by the MMR machinery, this would imply that MMR specifically inhibits the ZMM pathway at some point in S. uvarum. The weak effect or potential absence of the effect of sequence polymorphism on NCO formation suggests that heteroduplex DNA tracts, at least the way they form during NCO formation, escape the anti-recombinogenic effect of MMR in S. uvarum. A few comments about this could be added.
We have added discussion and citations regarding the biased repair of DSB to NCO in introgression, lines 380-386.
(8) The same applies to the fact that the CO number is lower in the natural cross compared to the fermentation cross, while the NCO number is the same. This suggests that under similar initiating Spo11-DSB numbers in both crosses, the decrease in CO is likely compensated by a similar increase in inter-sister recombination.
Thank you to the reviewer for this observation. We agree that this could explain some differences between the crosses.
(9) Introgressions represent only 10% of the genome, while the decrease in CO is at least 20%. This is a bit surprising especially in light of CO regulation mechanisms such as CO homeostasis that tends to keep CO constant. Could the authors comment on that?
We interpret these results to reflect two underlying mechanisms. First, the presence of heterozygous introgression does reduce the number of COs. Second, we believe the difference in COs reflects variation in recombination rate between strains. We note that CO homeostasis need not apply across different genetic backgrounds. Indeed, recombination rate is appreciated to significantly differ between strains of S. cerevisiae (Raffoux et al. 2018), and recombination rate variation has been observed between strains/lines/populations in many different species including Drosophila, mice, humans, Arabidopsis, maize, etc. We reference S. cerevisiae strain variability in the Introduction lines 128-130, and have added context in the Results lines 180-187, and Discussion lines 343-350.
(10) Finally, the frequency of NCOs in introgressed regions is about twice the frequency of CO in non-introgressed regions. Both CO and NCO result from Spo11-initiating DSBs.
This suggests that more Spo11-DSBs are formed within introgressed regions and that such DSBs specifically give rise to NCO. Could this be related to the lack of homolog engagement which in turn shuts down Spo11-DSB formation as observed in ZMM mutants by the Keeney lab? Could this simply result from better detection of NCO in introgressed regions related to the increased marker density, although the authors claim that NCO counts are corrected for marker resolution?
The effect noted by the reviewer remains despite the more conservative correction for marker density applied to NCO counts (as described in the response to Reviewer 1, comment #2). Given that CO+NCO counts in introgressed regions are not statistically different between crosses, it is likely that these regions are simply predisposed to a higher rate of DSBs than the rest of the genome. This is an interesting observation, however, and one that we would like to further explore in future work.
(11) What could be the explanation for chromosome 12 to have more shuffling in the natural cross compared to the fermentation cross which is deprived of the introgressed region?
We added this text to the Results, lines 323-327, "While it is unclear what potential mechanism is mediating the difference in shuffling on chromosome 12, we note that the rDNA locus on chromosome 12 is known to differ dramatically in repeat content across strains of S. cerevisiae (22–227 copies) (Sharma et a. 2022), and we speculate that differences in rDNA copy number between strains in our crosses could impact shuffling."
Technical points:
(12) In line 248, the authors removed NCO with fewer than three associated markers.
What is the rationale for this? Is the genotyping strategy not reliable enough to consider events with only one or two markers? NCO events can be rather small and even escape detection due to low local marker density.
We trust the genotyping strategy we used, but chose to be conservative in our detection of NCOs to account for potential sequencing biases.
(13) Line 270: The way homology is calculated looks odd to this reviewer, especially the meaning of 0.5 homology. A site is either identical (1 homology) or not (0 homology).
We've changed the language to better reflect what we are calculating (diploid sequence similarity; see comment #28). Essentially, the metric is a probability that two randomly selected chromatids--one from each parent--will share the same nucleotide at a given locus (akin to calculating the probability of homozygous offspring at a single locus). We average it along a segment of the genome to establish an expected sequence similarity if/when recombination occurs in that segment.
(14) Line 365: beware that the estimates are for mitotic mismatch repair (MMR). Meiotic MMR may work differently.
We removed the citation that refers exclusively to mitotic recombination. The statement regarding meiotic recombination is otherwise still reflective of results from Chen & Jinks-Robertson
(15) Figure 1: there is no mention of potential 4:0 segregations. Did the authors find no such pattern? If not, how did they consider them?
The program we used to call COs and NCOs (ReCombine's CrossOver program) can detect such patterns, but none were detected in our data.
Reviewer #3 (Public Review):
When members of two related but diverged species mate, the resulting hybrids can produce offspring where parts of one species' genome replace those of the other. These "introgressions" often create regions with a much greater density of sequence differences than are normally found between members of the same species. Previous studies have shown that increased sequence differences, when heterozygous, can reduce recombination during meiosis specifically in the region of increased difference. However, most of these studies have focused on crossover recombination, and have not measured noncrossovers. The current study uses a pair of Saccharomyces uvarum crosses: one between two natural isolates that, while exhibiting some divergence, do not contain introgressions; the other is between two fermentation strains that, when combined, are heterozygous for 9 large regions of introgression that have much greater divergence than the rest of the genome. The authors wished to determine if introgressions differently affected crossovers and noncrossovers, and, if so, what impact that would have on the gene shuffling that occurs during meiosis.
(1) While both crossovers and noncrossovers were measured, assessing the true impact of increased heterology (inherent in heterozygous introgressions) is complicated by the fact that the increased marker density in heterozygous introgressions also increases the ability to detect noncrossovers. The authors used a relatively simple correction aimed at compensating for this difference, and based on that correction, conclude that, while as expected crossovers are decreased by increased sequence heterology, counter to expectations noncrossovers are substantially increased. They then show that, despite this, genetic shuffling overall is substantially reduced in regions of heterozygous introgression. However, it is likely that the correction used to compensate for the effect of increased sequence density is defective, and has not fully compensated for the ascertainment bias due to greater marker density. The simplest indication of this potential artifact is that, when crossover frequencies and "corrected" noncrossover frequencies are taken together, regions of introgression often appear to have greater levels of total recombination than flanking regions with much lower levels of heterology. This concern seriously undercuts virtually all of the novel conclusions of the study. Until this methodological concern is addressed, the work will not be a useful contribution to the field.
We appreciate this concern. Please see response to comments #2 and #38. We further note that our results depicted in Figure 3 and 4 are not reliant on any correction or comparison with non-introgressed regions, and thus our results regarding sequence similarity and its effect on the repair of DSBs and the amount of genetic shuffling with/without introgression to be novel and important observations for the field.
Recommendations for the authors:
Reviewer #1 (Recommendations For The Authors):
(1) Line 149 - this sentence refers to a mixture of papers reporting somatic or meiotic recombination and as these processes are based on different crossover pathways, this should not be mixed. For example, it is known that in Arabidopsis MSH2 has a pro-crossover function during meiotic recombination.
Corrected
(2) What is unclear to me is how the crosses are planned. Line 308 shows that there were only two crosses (one "natural" and one "fermentation"), but I understand that this is a shorthand and in fact several (four?) different strains were used for the "fermentation cross". At least that's what I concluded from Fig. 1B and its figure caption. This needs to be further explained. Were different strains used for each fermentation cross, or was one strain repeated in several crosses? In Figure 1, it would be worth showing, next to the panel showing "fermentation cross", a diagram of how "natural cross" was performed, because as I understand it, panel A illustrates the procedure common to both types of crosses, and not for "natural cross".
We thank the reviewer for drawing our attention to confusion about how our crosses were created. We performed two crosses, as depicted in Figure 1A. The fermentation cross is a single cross from two strains isolated from fermentation environments. The natural cross is a single cross from two strains isolated from a tree and insect. Table S1 and the methods section "Strain and library construction" describe the strains used in more detail. We modified Figure 1 and the figure legend to help clarify this. See also response to comment #37.
(3) The authors should provide a more detailed characterization of the genetic differences between chromosomes in their hybrids. What is the level of polymorphism along the S. uvarum chromosomes used in the experiments? Is this polymorphism evenly distributed? What are the differences in the level of polymorphism for individual introgressions? Theoretically, this data should be visible in Figure 2D, but this figure is practically illegible in the present form (see next comment).
As suggested, we remade Figure 2D to only include chromosomes with an introgression present, and moved the remaining chromosomes to the supplements (Figure S11). The patterns of markers (which are fixed differences between the strains in the focal cross) should be more clear now. As we detail in the Methods line 507-508, we utilized a total of 24,574 markers for the natural cross and 74,619 markers for the fermentation cross (the higher number in the fermentation cross being due to more fixed differences in regions of introgression).
(4) Figure 2D should be prepared more clearly, I would suggest stretching the chromosomes, otherwise, it is difficult to see what is happening in the introgression regions for CO and NCO (data for SNPs are more readable). Maybe leave only the chromosomes with introgressions and transfer the rest to the supplement?
See previous comment.
(5) How are the Y scales defined for Figure 2D?
Figure 2D now includes units for the y-axis.
(6) Are increases in CO levels in fermentation cross-observed at the border with introgressions? This would indicate local compensation for recombination loss in the introgressed regions, similar to that often observed for chromosomal inversions.
We see no evidence of an increase in CO levels at the borders of introgressions, neither through visual inspection or by comparing the average CO rate in all fermentation windows to that of windows at the edges of introgressions. This is included in the Discussion lines 360-366, "While we are limited in our interpretations by only comparing two crosses (one cross with heterozygous introgression and one without introgression), these results are in line with findings in inversions, where heterozygotes show sharp decreases in COs, but the presence of NCOs in the inverted region (Crown et al., 2018; Korunes & Noor, 2019). However, unlike heterozygous inversions where an increase in COs is observed on freely recombining chromosomes (the inter-chromosomal effect), we do not see an increase in COs on the borders flanking introgression or on chromosomes without introgression."
(7) Line 336 - "We find positive correlations between CO counts..." - you should indicate here that between fermentation and natural crosses, it was quite hard for me to understand what you calculated.
We corrected the language as suggested.
(8) The term "homology" usually means "having a common evolutionary origin" and does not specify the level of similarity between sequences, thus it cannot be measured. It is used incorrectly throughout the manuscript (also in the intro). I would use the term "similarity" to indicate the degree of similarity between two sequences.
We corrected the language as suggested throughout the document.
(9) Paragraph 360 and Figure 3 - was the "sliding window" overlapping or non-overlapping?
We added clarifying language to the text in both places. We use a 101bp sliding window with 50bp overlaps.
(10) Line 369 - what is "...the proportion of bases that are expected to match between the two parent strains..."?
We clarified the language in this location, and hopefully changes associated with the comment about sequence similarity will make the comment even clearer in context.
(11) Line 378 - should it refer to Figure S1 and not Figure 4?
Corrected.
(12) Line 399 - should refer to Figure 4, not Figure 5.
Corrected
(13) Line 444-449 - the analysis of loss of shuffling in the context of the location of introgression on the chromosome should be presented in the result section.
We shifted the core of the analysis to the results, while leaving a brief summary in the discussion.
(14) The authors should also take into account the presence of indels in their analyses, and they should be marked in the figures, if possible.
We filtered out indels in our variant calling. However, we did analyze our crosses for the presence of large insertions and deletions (Table S2), which can obscure true recombination rates, and found that they were not an issue in our dataset.
Reviewer #2 (Recommendations For The Authors):
This reviewer suggests that the authors address the different points raised in the public review.
(1) This reviewer would like to challenge the relevance of the r-parameter in light of chromosome 12 which has no introgression and still a strong depletion in r in the fermentation cross.
We added this text to the Results, lines 377-381, "While it is unclear what potential mechanism is mediating the difference in shuffling on chromosome 12, we note that the rDNA locus on chromosome 12 is known to differ dramatically in repeat content across strains of S. cerevisiae (22–227 copies) (Sharma et a. 2022), and we speculate that differences in rDNA copy number between strains in our crosses could impact shuffling."
(2) This reviewer insists on making sure that NCO detection is unaffected by the marker density, notably in the highly polymorphic regions, to unambiguously support Figure 1C.
We've changed our correction for resolution to be more aggressive (see response to comment #2), and believe we have now adequately adjusted for marker density (see response to comment #38).
Reviewer #3 (Recommendations For The Authors):
I regret using such harsh language in the public review, but in my opinion, there has been a serious error in how marker densities are corrected for, and, since the manuscript is now public, it seems important to make it clear in public that I think that the conclusions of the paper are likely to be incorrect. I regret the distress that the public airing of this may cause. Below are my major concerns:
(1) The paper is written in a way that makes it difficult to figure out just what the sequence differences are within the crosses. Part of this is, to be frank, the unusual way that the crosses were done, between more than one segregant each from two diploids in both natural and fermentation cases. I gather, from the homology calculations description, that each of these four diploids, while largely homozygous, contained a substantial number of heterozygosities, so individual diploids had different patterns of heterology. Is this correct? And if so, why was this strategy chosen? Why not start with a single diploid where all of the heterologies are known? Why choose to insert this additional complication into the mix? It seems to me that this strategy might have the perverse effect of having the heterology due to the polymorphisms present in one diploid affect (by correction) the impact of a noncrossover that occurs in a diploid that lacks the additional heterology. If polymorphic markers are a small fraction of total markers, then this isn't such a great concern, but I could not find the information anywhere in the manuscript. As a courtesy to the reader, please consider providing at the beginning some basic details about the starting strains-what is the average level of heterology between natural A and natural B, and what fraction of markers are polymorphic; what is the average level of heterology between fermentation A and fermentation B in non-introgressed regions, in introgressed regions, and what fraction of markers are polymorphic? How do these levels of heterology compare to what has been examined before in whole-genome hybrid strains? It also might be worth looking at some of the old literature describing S. cerevisiae/S. carlsbergensis hybrids.
We thank the reviewer for drawing our attention to confusion about the cross construction. These crosses were conducted as is typical for yeast genetic crosses: we crossed 2 genetically distinct haploid parents to create a heterozygous diploid, then collected the haploid products of meiosis from the same F1 diploid. Because the crosses were made with haploid parents, it is not possible for other genetic differences to be segregating in the crosses. We have revised Figure 1 and its caption to clarify this. Further details regarding the crosses are in the Methods section "Strain and library construction" and in Supplemental Table S1. We only utilized genetic markers that are fixed differences between our parental strains to call CO and NCO. As we detail in the Methods line 507-508, we utilized a total of 24,574 markers for the natural cross and 74,619 markers for the fermentation cross (the higher number in the fermentation cross being due to more fixed differences in regions of introgression). We additionally revised Figure 2D (and Figure S11) to help readers better visualize differences between the crosses.
(2) There are serious concerns about the methods used to identify noncrossovers and to normalize their levels, which are probably resulting in an artifactually high level of calculated crossovers in Figure 2. As a primary indication of this, it appears in Figure 2 that the total frequency of events (crossovers + noncrossovers) in heterozygous introgressed regions are substantially greater than those in the same region in non-introgressed strains, while just shifting of crossovers to noncrossovers would result in no net increase. The simplest explanation for this is that noncrossovers are being undercounted in non-introgressed relative to introgressed heterozygous regions. There are two possible reasons for this: i. The exclusion of all noncrossover events spanning less than three markers means that many more noncrossovers in introgressed heterozygous regions than in non-introgressed. Assuming that average non-homology is 5% in the former and 1% in the latter, the average 3-marker event will be 60 nt in introgressed regions and 300 nt in non-introgressed regions - so many more noncrossovers will be counted in introgressed regions. A way to check on this - look at the number of crossover-associated markers that undergo gene conversion; use the fraction that involves < 3 markers to adjust noncrossover levels (this is the strategy used by Mancera et al.). ii. The distance used for noncrossover level adjustment (2kb) is considerably greater than the measured average noncrossover lengths in other studies. The effect of using a too-long distance is to differentially under-correct for noncrossovers in non-introgressed regions, while virtually all noncrossovers in heterozygous introgressed regions will be detected. This can be illustrated by simulations that reduce the density of scored markers in heterozygous introgressed regions to the density seen in non-introgressed regions. Because these concerns go to the heart of the conclusions of the paper, they must be addressed quantitatively - if not, the main conclusions of the paper are invalid.
We adjusted the correction factor (See also response to comment #2) and compared the average number of CO and NCO events in introgressed and non-introgressed regions between crosses (two comparisons: introgression CO+NCO in natural cross vs introgression CO+NCO in fermentation cross; non-introgression CO+NCO in natural cross vs non-introgression CO+NCO in fermentation cross). We found no significant differences between the crosses in either of the comparisons. This indicates that the distribution of total events is replicated in both crosses once we correct for resolution.
(3) It is important to distinguish the landscape of double-strand breaks from the landscape of recombination frequencies. Double-strand breaks, as measured by uncalibrated levels of Spo11-linked oligos, is a relative number - not an absolute frequency. So it is possible that two species could have a similar break landscape in terms of topography but have absolute levels higher in one species than in the other.
We agree with this statement, however, we have removed the relevant text to streamline our introduction.
(4) Lines 123-125. Just meiosis will produce mosaic genomes in the progeny of the F1; further backcrossing will reduce mosaicism to the level of isolated regions of introgression.
Adjusted the language to be more specific.
(5) Please provide actual units for the Y axes in Figure 2D.
We have corrected the units on the axes.
(6) Tables (general). Are the significance measures corrected for multiple comparisons?
In Table 3, the cutoff was chosen to be more conservative than a Bonferroni corrected alpha=0.01 with 9 comparisons (0.0011). In text, any result referred to as significant has an associated hypothesis test with a p-value less than its corresponding Bonferroni-corrected alpha of 0.05. This has been clarified in the caption for Table 3 and in the text where relevant.
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drive.google.com drive.google.com
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Para criar atividades de aprendizagem em ambientes digitais temos de combinar objetivos pedagógicos com as oportunidades oferecidas pela tecnologia, promovendo interação e colaboração entre os estudantes. Acho essencial definir metas claras e propor atividades relevantes que incentivem uma participação ativa,Os momentos síncronos e assíncronos, permite um maior envolvimento dos estudantes, Uma aprendizagem ativa, baseada na resolução problemas, também deve ser incentivada, com desafios práticos que permitam aplicar o conhecimento de forma crítica. Devemos contar com um feedback contínuo, tanto por parte do professor como dos colegas, que ajuda os estudantes a atingir uma aprendizagem mais rica e reflexiva. Para garantir a inclusão e acessibilidade, devemos criar atividades flexíveis, que se adaptem às necessidades de todos os estudantes. Ao usarmos ferramentas tecnológicas adequadas facilitamos a criação de um ambiente interativo e estimulante.
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scontent.ftlv16-1.fna.fbcdn.net scontent.ftlv16-1.fna.fbcdn.net
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Task & Talk
Task and Talk is Clearly based in the Lewis signaling game. However this setup seems to lead to entangled solutions at least for the minimal number of required signals.<br /> A needs to send one of three signals - the one he does not need. Then B needs to send one of four symbols for the state of one then the other (order is selected by symmetry breaking and learned thoroug reinfocement.) In this minimal version the signals are reused. If agent A has 8 signals he can respond fully without needed a second round.
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64
so 64 states and an state space that both symmetrical and has three normal subgroups - so agent could learn to choose composable representations if one provides that right incentives to pick these over other equilibria.
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Specifically, in a sequence of ‘negative’ resultsculminating in a ‘positive’ one, we find that whileagents always successfully invent communicationprotocols and languages to achieve their goalswith near-perfect accuracies, the invented lan-guages are decidedly not compositional, inter-pretable, or ‘natural’;
so AFAIK this is what we expect in RL - a quick and efficent solution not the Oxford English dictionary. Or that solving a maze should be done with style.
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at are the conditions that lead to theemergence of human-interpretable or composi-tional grounded language?
so they just mean compsitional language
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social-media-ethics-automation.github.io social-media-ethics-automation.github.io
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This trend brought complicated issues of authenticity because presumably there was some human employee that got charged with running the company’s social media account. We are simultaneously aware that, on the one hand, that human employee may be expressing themselves authentically (whether playfully or about serious issues), but also that human is at the mercy of the corporation and the corporation can at any moment tell that human to stop or replace that human with another.
This paragraph effectively captures the tension between authenticity and corporate control in social media management. It highlights the duality where an employee may express genuine thoughts but remains bound to the corporation's directives, making their authenticity conditional and fragile.
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university.pressbooks.pub university.pressbooks.pub
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Edit Image.
The xyz window opens up. add screen shot of that window (without clicking any of the options first)
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Perform one or more of the following edit actions: Crop, Scale, Image Rotation
I am not sure how much detail we want to give here. Not sure how frequently this feature is being used. If we want to give more info, we could list the steps for each edit action. They differ a lot and have some slightly tricky steps. Especially the last step differs (sometimes it's enough to click Apply, sometimes it's necessary to click Save Edits
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⚠️ Editing an image may break how the image appears where you had already inserted it before.
We are not sure in what cases already inserted images are affected.
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www.tumblr.com www.tumblr.com
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La Importancia de una Calefacción Eficiente
Eficiencia Energética y Sostenibilidad
Las soluciones modernas de calefacción, como bombas de calor y sistemas de aislamiento avanzados, permiten un consumo energético reducido, mejorando el confort y minimizando el impacto ambiental. Adoptar prácticas conscientes, como el uso adecuado de termostatos y la optimización de la ventilación, complementa estos esfuerzos.
Mantenimiento y Reparación
El mantenimiento regular de sistemas de calefacción es esencial para garantizar su eficiencia. La limpieza de radiadores, revisión de tuberías y mantenimiento de calderas son cruciales para prevenir fallos y optimizar el rendimiento.
Tipos de Sistemas de Calefacción
Los sistemas disponibles incluyen calderas de gas, bombas de calor y calefacción eléctrica. La elección del sistema adecuado depende del consumo energético, emisiones, costos de mantenimiento y necesidades específicas del hogar.
Aislamiento y Ventilación
Un buen aislamiento y una ventilación eficiente son vitales para reducir el consumo energético y mantener la salud del hogar. Controlar la humedad también ayuda a evitar problemas estructurales y de salud.
Consejos Prácticos
Los termostatos inteligentes optimizan el uso de la calefacción, programando su funcionamiento de manera eficiente y evitando el desperdicio de energía. Invertir en estos dispositivos contribuye a reducir significativamente las facturas energéticas.
En conjunto, el artículo enfatiza la importancia de una combinación de tecnologías avanzadas y prácticas adecuadas para lograr una calefacción eficiente y sostenible.
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www.repubblica.it www.repubblica.it
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Carlo Buontempo, der Leiter des europäischen Copernicus-Programms, setzt sich in einem Interview der Repubblica mit dem bei Klimaleugner:innen beliebten Argument auseinander, früher sei es auch oft heiß gewesen. Er verweist auf öffentlich zugängliche Daten zur globalen Erhitzung wie die von ERA5.
ERA5 Climate Data Store: https://cds.climate.copernicus.eu/datasets/reanalysis-era5-single-levels?tab=overview
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docs.google.com docs.google.com
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vxcbvbxvcbxcvxcvxc
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hcommons.org hcommons.org
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ScholarlyHub (scholarlyhub.org)
Oh this was such a nice project... so sad it dissappeared...
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Below I discuss several examples of infrastructural experiments groupedaround four areas: (1) “who has access?”; (2) “what counts?”; (3) “whatmatters?”; and (4) “how are relations reconfigured?” They are intendedto be taken as illustrative rather than exhaustive, overlapping rather thanmutually exclusive.
Not sure I am following this step...
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Rather than focusingsimply on optimizing systems through feedback loops or composing newimproved ones that will recede into the background, such experiments mayserve to facilitate collective inquiry into who and what research is for, aswell as “infrastructural imagination” about how it may be organized differ-ently.16 Infrastructures may thus serve as experimental “sites and devicesfor intervention in the ‘composition of the world,’”17 as well as “wheremultiple agents meet, engage, and produce new worlds.”18
Experiments both make existingn 'natural' systems more visible while providing new imaginaries. Quite similar
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“infrastructural experiments,
Sounds similar to how we perceive experimental publishing
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padlet.com padlet.com
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Who will this research benefit, and how?
The managers of water companies.
They could formulate corresponding strategic plans for the enterprise in a more macro-level.
Customers.
They will pay more attention to the conservation and use of water resources and provide necessary and timely feedback and suggestions to relevant departments to ensure the maximum water quality safety.
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How many sources are cited in the ‘deficiency/research gap’ section?
5
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slejournal.springeropen.com slejournal.springeropen.com
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branding
I also wonder about this on the departmental level. Some faculty will be more comfortable or experienced with these approaches than others, so, I think it's important for chairs and directors to be having these conversations with faculty as well.
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www.biorxiv.org www.biorxiv.org
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Reviewer #1 (Public review):
Assessment:
This fundamental work advances our understanding of navigation and path integration in mammals by using a clever behavioral paradigm. The paper provides compelling evidence that mice are able to create and use a cognitive map to find "short cuts" in an environment, using only the location of rewards relative to the point of entry to the environment and path integration, and need not rely on visual landmarks.
Summary:
The authors have designed a novel experimental apparatus called the 'Hidden Food Maze (HFM)' and a beautiful suite of behavioral experiments using this apparatus to investigate the interplay between allothetic and idiothetic cues in navigation. The results presented provide a clear demonstration of the central claim of the paper, namely that mice only need a fixed start location and path integration to develop a cognitive map. The experiments and analyses conducted to test the main claim of the paper -- that the animals have formed a cognitive map -- are conclusive and include many thoughtfully designed control experiments to eliminate alternatives.
Strengths:
The 90 degree rotationally symmetric design and use of 4 distal landmarks and 4 quadrants with their corresponding rotationally equivalent locations (REL) lends itself to teasing apart the influence of path integration and landmark-based navigation in a clever way. The authors use a complete set of experiments and associated controls to show that mice can use a start location and path integration to develop a cognitive map and generate shortcut routes to new locations.
Weaknesses:
There were no major weaknesses identified that were not addressed during revisions.
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Reviewer #3 (Public review):
Summary:
How is it that animals find learned food locations in their daily life? Do they use landmarks to home in on these learned locations or do they learn a path based on self-motion (turn left, take ten steps forward, turn right, etc.). This study carefully examines this question in a well-designed behavioral apparatus. A key finding is that to support the observed behavior in the hidden food arena, mice appear to not use the distal cues that are present in the environment for performing this task. Removal of such cues did not change the learning rate, for example. In a clever analysis of whether the resulting cognitive map based on self-motion cues could allow a mouse to take a shortcut, it was found that indeed they are. The work nicely shows the evolution of the rodent's learning of the task, and the role of active sensing in the targeted reduction of uncertainty of food location proximal to its expected location.
Strengths:
A convincing demonstration that mice can synthesize a cognitive map for the finding of a static reward using body frame-based cues. Showing that uncertainty of final target location is resolved by an active sensing process of probing holes proximal to the expected location. Showing that changing the position of entry into the arena rotates the anticipated location of the reward in a manner consistent with failure to use distal cues.
Weaknesses:
Weaknesses: The Reviewing Editor felt that previously identified weaknesses from Reviewer #3 were adequately addressed in the final manuscript.
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Author response:
The following is the authors’ response to the previous reviews.
I have added a paragraph that addresses the issue of how landmarks might be used and why they are not. The suggestions made in the "Weaknesses" paragraph were concise and excellent and have directly incorporated them into my revised manuscript. This text appears on Page 21 and is shown below. I hope that this is what the editors and reviewers were looking.
The requested revision is the second paragraph.
The first paragraph was not written in response to reviews but inspired by a recent paper by Mahdev et al (2024) - https://doi.org/10.1038/s41593-024-01681-9. I had already requested to add this reference and was encouraged to do so by the Editors. The Mahdev et al paper was very surprising in that it showed that path integration is not constant but that its "gain" can be recalibrated by selfmotion signals. I wondered whether this unexpected capacity extended to path integration also recalibrating the cognitive map and thereby generating the shortcutting behavior we observe. I suggested that, at an abstract level, this would correspond to "coordinate transformation" of the cognitive map. I realize that this is entirely speculative. If the Editors feel that it does not add much to the manuscript and that the speculation goes to far, I will remove the first paragraph and re-submit.
Added text. P21 and just before the heading: " Implications for theories of hippocampal representations of spatial maps" There were no other changes made in the paper.
"Path integration uses self-motion signals to update the animal's estimated location on its internal cognitive map. Path integration gain has been shown to be plastic and regulated by landmarks (52). Remarkably, a recent study has revealed that path integration gain can also be directly recalibrated by self-motion signals alone (53), albeit not as effectively as by landmarks (52, 53). An interesting question for future research is whether self-motion signals can also recalibrate the coordinates of a cognitive map. From this perspective, the Target B to Target A shortcut requires a transformation of the cognitive map coordinates so that the start point is now Target B.
Extensive research has shown that external cues can control hippocampal neuron place fields (11, 12, 54) and the gain of the path integrator (52), making the failure of mice in our study to use such cues puzzling. The failure to use landmarks may be related to our task being low stakes and our pretraining procedure teaching the mouse that such cues are not necessary. Our results may not generalize to more natural conditions where many reliable prominent cues are available, and where there is urgency to find food or water while avoiding predation (55). Under these more naturalistic conditions the use of distal cues to rapidly find a food reward is more likely to be observed."
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www.biorxiv.org www.biorxiv.org
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eLife Assessment
This study presents a valuable finding in understanding the role of plectin in the development and progression of hepatocellular carcinoma (HCC). The evidence supporting the conclusions is convincing because multiple orthogonal ways were used to demonstrate the requirement of this target in liver cancer models. However, the study is incomplete as the downstream molecular activities of plectin that mediate the cancer phenotypes were not fully evaluated.
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Reviewer #1 (Public review):
Summary:
This study investigated the role of plectin, a cytoskeletal crosslinker protein, in liver cancer formation and progression. Using the liver-specific Plectin knockout mouse model, the authors convincingly showed that PLECTIN is critical for hepatocarcinogenesis, as functional inhibition of plectin suppressed tumor formation in several models. They also provided evidence to show that inhibition of plectin inhibited HCC cell invasion and reduced metastatic outgrowth in the lung. Mechanistically, they suggested that plectin inhibition attenuated FAK, MAPK/ERK, and PI3K/AKT signaling.
Strengths:
The authors generated a liver-specific plectin knockout mouse model. By using DEN and sgP53/MYC models, the authors convincingly demonstrated an oncogenic role of PLECTIN in HCC development. plecstatin-1 (PST), as a plectin inhibitor, showed promising efficacy in inhibiting HCC growth, which provides a basis for potentially treating HCC using PST.
The MIR images for tracking tumor growth in animal models were compelling. The high-quality confocal images and related qualifications convincingly showed the impact of plectin functional inhibition on contractility and adhesions in HCC cells.
Weaknesses:
The conclusions of this paper are primarily well supported by data. However, some claims were not fully supported by the data presented.
The authors suggest that plectin controls oncogenic FAK, MAPK/Erk, and PI3K/Akt signaling in HCC cells, representing the mechanisms by which plectin promotes HCC formation and progression. However, the effect of plectin inactivation on these signaling was inconsistent in Huh7 and SNU-475 cells (Figure 3D), despite similar cell growth inhibition in both cell lines (Figure 2G). For example, pAKT and pERK were only reduced by plectin inhibition in SNU-475 cells but not in Huh7 cells. In addition, pFAK was not changed by plectin inhibition in both cells, and the ratio of pFAK/FAK was increased in both cells. Thus, it is hard to convince me that plectin promotes HCC formation and progression by regulating these signalings. Overall, the mechanistic studies in this manuscript lack sufficient depth.
The authors claimed that plectin inactivation inhibits HCC invasion and metastasis using in vitro and in vivo models. However, the results from in vivo models were not as compelling as the in vitro data. The lung colonization assay is not an ideal in vivo model for studying HCC metastasis and invasion, especially when plectin inhibition suppresses HCC cell growth and survival. Using an orthotopic model that can metastasize into the lung or spleen could be much more convincing for an essential claim. Also, in Figure 6H, histology images of lungs from this experiment need to be shown to understand plectin's effect on metastasis better. Figure 6G, it is unclear how many mice were used for this experiment. Did these mice die due to the tumor burdens in the lungs?
The whole paper used inhibition strategies to understand the function of plectin. However, the expression of plectin in Huh7 cells is low (Figure 1D). It might be more appropriate to overexpress plectin in this cell line or others with low plectin expression to examine the effect on HCC cell growth and migration.
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Reviewer #2 (Public review):
Summary:
Plectin is a cytolinker that associates with all three main components of the cytoskeleton and intercellular junctions and is essential for epithelial tissue integrity. Previous reports showed that PLEC regulates tumor growth and metastasis in different cancers. In this manuscript, the authors described PLEC as a target in the initiation and growth of HCC. They showed that inhibiting PLEC reduced tumorigenesis in different in vitro and in vivo HCC models, including in a xenograft model, DEN model, oncogene-induced HCC model, and a lung metastasis model. Mechanistically, the authors showed that inhibiting PLEC results in a disorganized cytoskeleton, deficiency in cell migration, and changes in relevant signaling pathways.
Strengths:
In general, the data are shown in multiple ways and support the main conclusion of the manuscript. The results add to the field by highlighting the importance of cellular mechanics in cancer progression.
Weaknesses:
(1) The annotation of mouse numbers is confusing. In Figures 2A B D E F, it should be the same experiment, but the N numbers in A are 6 and 5. In E and F they are 8 and 3. Similarly, in Figure 2H, in the tumor size curve, the N values are 4,4,5,6. In the table, N values are 8,8,10,11 (the authors showed 8,7,8,7 tumors that formed in the picture).
(2) In Figure 3D and Figure S3C, the changes in most of the proteins/phosphorylation sites are not convincing/consistent. These data are not essential for the conclusion of the paper and WB is semi-quantitative. Maybe including more plots of the proteins from proteomic data could strengthen their detailed conclusions about the link between Plectin and the FAK, MAPK/Erk, PI3K/Akt pathways as shown in 3E.
(3) Figure S7A and B, The pictures do not show any tumor, which is different from Figure 7A and B (and from the quantification in S7A lower right). Is it just because male mice were used in Figure 7 and female mice were used in Figure S7? Is there literature supporting the sex difference for the Myc-sgP53 model?
(4) Figure 2F, S2A, PleΔAlb mice more frequently formed larger tumors, as reflected by overall tumor size increase. The interpretation of the authors is "possibly implying reduced migration or increased cohesion of plectin-depleted cells". It is quite arbitrary to make this suggestion in the absence of substantial data or literature to support this theory.
(5) Mutation or KO PLEC has been shown to cause severe diseases in humans and mice, including skin blistering, muscular dystrophy, and progressive familial intrahepatic cholestasis. Please elaborate on the potential side effects of targeting plectin to treat HCC.
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Reviewer #3 (Public review):
Summary:
In this manuscript, Outla Z et al described the analysis of plectin in HCC pathogenesis. Specifically, it was found that elevated plectin levels in liver tumors, correlated with poor prognosis for HCC patients. Mechanistically, it showed that plectin-dependent disruption of cytoskeletal networks leads to the attenuation of oncogenic FAK, MAPK/Erk, and PI3K/AKT signals. Finally, the authors showed that plectin inhibitor plecstatin-1 (PST) is well-tolerated and capable of overcoming therapy resistance in HCC.
Strengths:
The studies of plectin are not entirely novel (Pubmed: 36613521). Nevertheless, the current manuscript provides a much more detailed mechanistic study and the results have translational implications. Additional strengths include convincing cell biology data, such as plectin regulates cytoskeletal networks, and HCC migration/invasion.
Weaknesses:
Multiple major issues are noted, and the conclusion is not well supported by the data presented.
(1) The rationale for using Huh7 cells in the manuscript is not well explained as it has the lowest plectin expression levels.
(2) The KO cell experiments should be supplemented with overexpression experiments.
(3) There is significant concern that while ablation of Ple led to reduced tumor number, these mice had larger tumors. The data indicate that plectin may have distinct roles in HCC initiation versus progression. The data are not well explained and do not fully support that plectin promotes hepatocarcinogenesis.
(4) Figure 3 showed that plectin does not regulate p-FAK/FAK expression. Therefore, the statement that plectin regulates the FAK pathway is not valid. Furthermore, there are too many variables in turns of p-AKT and p-ERK expression, making the conclusion not well supported.
(5) The studies of plecstatin-1 in HCC should be expanded to a panel of human HCC cells with various plectin expression levels in turns of cell growth and cell migration. The IC50 values should be determined and correlate with plectin expression.
(6) One of the major issues is the mechanistic studies focusing on plectin regulating HCC migration/metastasis, whereas the in vivo mouse studies focus on HCC formation (Figures 3 and 7). These are distinct processes and should not be mixed.
(7) Figure 7B showed that Ple KO mice were treated with PST, but the data are not presented in the manuscript. Tumor cell proliferation and apoptosis rates should be analyzed as well.
(8) The status of FAK, AKT, and ERK pathway activation was not analyzed in mouse liver samples. In Figure 7D, most of the adjusted p-values are not significant.
(9) There is no evidence to support that PST is capable of overcoming therapy resistance in HCC. For example, no comparison with the current standard care was provided in the preclinical studies.
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drive.google.com drive.google.com
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"Ultimately, government policies should aim to both maximize the development gains of migration—for the migrants, origin societies, and destination societies—and provide refugees with adequate international protection."
Annotation #3: This quote made me see migration not just as an economic or humanitarian issue but as a way to boost development. The author shows that when migration is well-managed, it benefits both the country migrants come from and the one they move to, which can help reduce inequality. This links to today’s question about whether migration increases inequality by suggesting that, with the right policies, migration can actually lower inequality.
Related Article: The article "Migration and Development" discusses how migration helps development through remittances and sharing ideas, supporting the view that policies can turn migration into a tool for reducing inequality. https://migrationobservatory.ox.ac.uk/resources/primers/migration-and-development/
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"Climate change is compounding the economic drivers of migration. About 40 percent of the world’s population—3.5 billion people—live in places highly exposed to the impacts of climate change."
Annotation #2: This section makes me wonder how international rules will need to change to handle the growing number of people moving because of climate change. Will these climate migrants increase inequality in rich countries, or could this be a chance for better opportunities if it's managed well? This connects to the question about migration and trade, showing how things like climate change could affect inequality, depending on how countries set up their policies.
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"Where migrants stand in the Match and Motive Matrix is determined in part by destination countries’ policies."
Annotation #1: This part shows the author’s point that migration results don’t just depend on the migrants themselves but also a lot on the rules of the countries they move to. The author explains that these rules decide how well the migrants’ skills fit the needs of the country they move to. If they fit well, migration can be more helpful for both the migrants and the country. This connects to today’s question about how migration and free trade can cause more inequality because these rules can either make inequality better or worse, depending on how they’re set up.
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"When destination countries adopt restrictive policies, their neighbors can also be affected, especially those through which migrants are transiting. Transit countries become substitute destinations when barriers prevent migrants from moving onward. Distressed migrants stay for months, and at times years"
Epiphanies:
This section reminded me of AP microeconomics when we learned about substitute goods and services. When the main target destination increases its restrictive policies, the demand for the substitute/ transition countries increases because the migrants have to go somewhere.
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"When migrants do not bring skills and attributes in demand at their destination, the costs to destination countries exceed the benefits. If there are gains for migrants and origin countries, these gains are not sustainable unless destination countries take action to reduce and manage their own costs"
Questions:
How can the costs and benefits for destination countries of migrant workers be modelled? Similarly, what are the efforts that destination countries can employ to reduce and manage their costs as stated in the article?
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www.gmm1.co.uk www.gmm1.co.uk
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A Mistake of Wrong Fuelling Could Cause Big Damage
This is why diesel in petrol tanks damages the system and the car stops running A mistake of filling the wrong fuel in the tank of your car can prove lethal if you fail to realise it soon. Fuel is used by mechanical parts of a car to produce energy and run it, so damage is mainly done to the engine and its parts. Always pay attention to fuelling and never take it for granted.
The problem of not accepting the mistake also makes the problem gigantic. Whenever you get a hint of committing a mistake after filling the wrong fuel, stop persisting with it. Check the possibility, and try to fix it without any delay. In routine, you do not pay attention and start filling the car tank, but if the car is not yours, then be careful.
Similarly, when you go abroad and do not know about fuel dispenser codes, the possibility of making a mistake increases. It means anything other than routine could lead you to the blunder of the wrong fuel. People in a hurry could do this and keep continuing with the mistake without realising the blunder. Petrol in diesel tank causes erosion of mechanical parts’ surfaces due to high friction.
Solutions are present, but first, avoid this blunder because the cost could be very high and you may need to change the car or its engine. Petrol engine cars make use of fuel differently, so diesel does not suit its mechanism of producing energy. Petrol burns and gives the energy to pull, but diesel does not burn.
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docdrop.org docdrop.orgview2
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Billings, 1994). Conclusion Schools such as Seguin High School are faced with a special challenge. To significantly alter the stubborn pattern of underachievement, they need to become authentically caring institutions. To become authentically caring institutions, the'y need to at once stop sub-tracting resources from youth and deal with th~ effects of subtraction. Although it is up to each school to determine what a more additive perspective might entail, my study suggests that an important point of departure is a critical examination of the existing curriculum. The operant model of schooling structurally deprives acculturated, U.S.-born youth o
Combatting the problem of poor achievement in institutions such as Seguin High School requires real attention to the students. In creating true, loving schools, schools can meet the needs of diverse students and counteract the consequences of subtraction of resources. The suggestion that we must evaluate the curriculum as we know it is important. This ensures that schools offer a broader and more fulfilling educational experience that is more responsive to the cultural and personal desires of US-born children.
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tried to talk to as many of them as possible and to incorporate their voices and experiences into this ethnographic account. Although my study makes use of quantitative data, the key modes of data collection are based on participant observation and open-ended interviews with individuals and with groups of students. Group interviews enabled me not only to tap into peer-group culture but also to investigate the social, cultural, and linguistic divisions that I observed among teenagers at Seguin. Before elaborating my framework, I will first address relevant survey findings that pertain to parental education, schooling orientations, and generational differences in achievement.~ First, students' parental education levels are very low, hovering around nine years of schooling completed for th
A diverse sample of voices and experiences is arguably valuable in an ethnographic analysis. Participant observation and open-ended interviewing – both one-to-one and in groups – allows researchers to better appreciate the subtle social dynamics involved. Group interviews are especially useful since they allow one to get inside peer-group cultures and reveal the social, cultural and linguistic fractures that might be invisible from other methods.
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www.biorxiv.org www.biorxiv.org
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eLife Assessment
This study presents a valuable examination of the prevalence of interactions between amino acids from different periods of Earth's history and coenzymes. While the premise of this work is well founded and the analysis is solid, with more data, the interpretation could change. This manuscript would be of interest to evolutionary biologists and biophysicists.
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hcommons.org hcommons.org
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it is never changed from above.
It is never changed well from above...
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Modified by scope and often by conflicting con-ventions, infrastructure takes on transparency by plugging into other infrastruc-tures and tools in a standardized fashion.
This is where I struggle with folks implementing infrastructures. I am not sure infrastructures need to rely on standardisation
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Infrastructure both shapes and is shapedby the conventions of a community of practice (e.g., the ways that cycles ofday-night work are affected by and affect electrical power rates and needs).
This also reflects infrastructures' inherent conservatism.
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Perhaps most important of all,what values and ethical principles do we inscribe in the inner depths of the builtinformation environment (Goguen, 1997; Hanseth & Monteiro, 1996; Hanseth,Monteiro, & Hatling, 1996)?
Lots of our project work concerned with this question of course.
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www.biorxiv.org www.biorxiv.org
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eLife Assessment
This revised study provides valuable information on the single nucleus RNA sequencing transcriptome, pathways, and cell types in pig skeletal muscle in response to conjugated linoleic acid (CLA) supplementation. Based on the comprehensive data analyses, the data are considered compelling and provide new insight into the mechanisms underlying intramuscular fat deposition and muscle fiber remodeling. The revised study clarifies major aspects of its methodology and analysis, addresses previous reviewer concerns, and contributes significantly to the understanding of nutritional strategies for fat infiltration in pig muscle.
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Reviewer #1 (Public review):
In this revised manuscript, the authors aim to elucidate the cytological mechanisms by which conjugated linoleic acids (CLAs) influence intramuscular fat deposition and muscle fiber transformation in pig models. They have utilized single-nucleus RNA sequencing (snRNA-seq) to explore the effects of CLA supplementation on cell populations, muscle fiber types, and adipocyte differentiation pathways in pig skeletal muscles. Notably, the authors have made significant efforts in addressing the previous concerns raised by the reviewers, clarifying key aspects of their methodology and data analysis.
Strengths:
(1) Thorough validation of key findings: The authors have addressed the need for further validation by including qPCR, immunofluorescence staining, and western blotting to verify changes in muscle fiber types and adipocyte populations, which strengthens their conclusions.
(2) Improved figure presentation: The authors have enhanced figure quality, particularly for the Oil Red O and Nile Red staining images, which now better depict the organization of lipid droplets (Figure 7A). Statistical significance markers have also been clarified (Figure 7I and 7K).
Weaknesses:
(1) Cross-species analysis and generalizability of the results: Although the authors could not perform a comparative analysis across species due to data limitations, they acknowledged this gap and focused on analyzing regulatory mechanisms specific to pigs. Their explanation is reasonable given the current availability of snRNA-seq datasets on muscle fat deposition in other human and mouse.
(2) Mechanistic depth in JNK signaling pathway: While the inclusion of additional experiments is a positive step, the exploration of the JNK signaling pathway could still benefit from deeper analysis of downstream transcriptional regulators. The current discussion acknowledges this limitation, but future studies should aim to address this gap fully.
(3) Limited exploration of other muscle groups: The authors did not expand their analysis to additional muscle groups, leaving some uncertainty regarding whether other muscle groups might respond differently to CLA supplementation. Further studies in this direction could enhance the understanding of muscle fiber dynamics across the organism.
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Reviewer #2 (Public review):
Summary:
This study comprehensively presents data from single nuclei sequencing of Heigai pig skeletal muscle in response to conjugated linoleic acid supplementation. The authors identify changes in myofiber type and adipocyte subpopulations induced by linoleic acid at depth previously unobserved. The authors show that linoleic acid supplementation decreased the total myofiber count, specifically reducing type II muscle fiber types (IIB), myotendinous junctions, and neuromuscular junctions, whereas type I muscle fibers are increased. Moreover, the authors identify changes in adipocyte pools, specifically in a population marked by SCD1/DGAT2. To validate the skeletal muscle remodeling in response to linoleic acid supplementation, the authors compare transcriptomics data from Laiwu pigs, a model of high intramuscular fat, to Heigai pigs. The results verify changes in adipocyte subpopulations when pigs have higher intramuscular fat, either genetically or diet-induced. Targeted examination using cell-cell communication network analysis revealed associations with high intramuscular fat with fibro-adipogenic progenitors (FAPs). The authors then conclude that conjugated linoleic acid induces FAPs towards adipogenic commitment. Specifically, they show that linoleic acid stimulates FAPs to become SCD1/DGAT2+ adipocytes via JNK signaling. The authors conclude that their findings demonstrate the effects of conjugated linoleic acid on skeletal muscle fat formation in pigs, which could serve as a model for studying human skeletal muscle diseases.
Strengths:
The comprehensive data analysis provides information on conjugated linoleic acid effects on pig skeletal muscle and organ function. The notion that linoleic acid induces skeletal muscle composition and fat accumulation is considered a strength and demonstrates the effect of dietary interactions on organ remodeling. This could have implications for the pig farming industry to promote muscle marbling. Additionally, these data may inform the remodeling of human skeletal muscle under dietary behaviors, such as elimination and supplementation diets and chronic overnutrition of nutrient-poor diets. However, the biggest strength resides in thorough data collection at the single nuclei level, which was extrapolated to other types of Chinese pigs.
Weaknesses:
Although the authors compiled a substantial and comprehensive dataset, the scope of cellular and molecular-level validation still needs to be expanded. For instance, the single nuclei data suggest changes in myofiber type after linoleic acid supplementation, but these findings need more thorough validation. Further histological and physiological assessments are necessary to address fiber types and oxidative potential. Similarly, the authors propose that linoleic acid alters adipocyte populations, FAPs, and preadipocytes; however, there are limited cellular and molecular analyses to confirm these findings. The identified JNK signaling pathways require additional follow-ups on the molecular mechanism or transcriptional regulation. However, these issues are discussed as potential areas for future exploration. While various individual studies have been conducted on mouse/human skeletal muscle and adipose tissues, these have only been briefly discussed, and further investigation is warranted. Additionally, the authors incorporate two pig models into their results, but they only examine one muscle group. Exploring whether other muscle groups respond similarly or differently to linoleic acid supplementation would be valuable. Furthermore, the authors should discuss how their results translate to human and pig nutrition, such as the desirability and cost-effectiveness for pig farmers and human diets high in linoleic acid. Notably, while the single nuclei data is comprehensive, there needs to be a statement on data deposition and code availability, allowing others access to these datasets.
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docdrop.org docdrop.orgview2
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part of her pedagogy. Teachers must not merely take courses that tell them how to treat their students as multicultural clients, in ocher words, those that cell them how co identify differences in interac-tional or communicative strategies and remediate appropri-ately. They muse also learn about the brilliance the students bring with them "in their blood." Until they appreciate the wonders of the cultures represented before them - and they cannot do chat without extensive study most appropriately begun in college-level courses - they cannot appreciate the potential of those who sit
It’s important to know that all students are different in their learning preferences and social orientation. If we design the classroom to accommodate these differences, including the demand for movement and interaction, we can promote the inherent talents of African-American boys. This helps to make the learning more diverse and participatory as well as less likely to incur negative consequences from such students in a classroom environment that doesn’t offer such an opportunity.
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earcher Harry Morgan documents in a 1990 study what most of us who have worked with African-American children have learned intuitively: that African-American children, more than white, and boys more than girls, initiate interac-tions with peers in the classroom in performing assigned tasks. Morgan concludes that a classroom that allows for greater movement and interaction will better facilitate the learning and social styles of African-American boys, while one that disallows such activ
There is an important point that each student may have different learning styles and social needs. If we are able to set up a classroom to support these difference and most importantly to accommodate the need for movement and interaction, we can nurture African-American boys’ inherent qualities. Not only does it create an inclusive and engaging learning experience, but it also helps reduce negative repercussions these students may receive in a more traditional classroom environment.
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www.biorxiv.org www.biorxiv.org
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eLife Assessment
This important study addresses two questions: (i) how danger signaling is altered for people with childhood adversities, and (ii) how this differs across different operationalizations of adversity. The latter is of particularly broad interest to multiple fields, given that childhood adversity is operationalized very differently across the literature. The study provides compelling evidence using a large sample size and rigorous statistical methods. These data will be of interest to scientists and clinicians interested in early life adversity, statistical approaches for quantifying stress exposure, or aversive learning.
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