The mechanism of superlubricity at the sliding interfaces of materials is studied. Dienwiebel and co-researchers have investigated the superlubricity of graphite using a home built frictional force microscope. They have also investigated the role of incommensurability in the origin of the ultralow friction of graphite.

Diamond like carbon (DLC) film is a widely researched material to combat friction and wear in a number of applications, owing to its impressive tribological properties and low deposition costs. Tribological properties of DLC films sliding against each other are investigated and they are found to display super low friction under specific conditions.

Moving mechanical assemblies’ failure due to friction and wear are a major concern in today's world. Different types of lubricants are employed to minimize friction. Though this helps to improve the lifetime of mechanical systems, researchers quest for a perfect lubricant to achieve lowest friction and wear possible with no harmful additives or chemicals.

The arcuate nucleus, a subregion of the hypothalamus has been shown to be a very important brain region that controls food intake

Neurons within this region have been shown to control feeding in a reciprocal manner. POMC-expressing neurons are activated by satiety signals are reduce food intake while AgRP-expressing neurons are activated by starvation and increase food intake.

These neurons have been proposed to be the neural substrate for satiety and hunger respectively.

The application of macroscopic laws of friction to the nanoscale region remained controversial. Mo and his team used molecular dynamics simulations to study friction laws in dry nanoscale contacts. They have investigated the effect of number of atoms in chemical contact in friction and reported the relationship between contact area and friction force at the nanoregime.

Research in superlubricity is gaining interest due to its potential applications in mechanical systems to reduce the friction and wear related failures. Various researchers proposed different materials to achieve near zero friction. Eventhough these materials shows some promise, most materials are perfectly crystalline (which is not the case in real life) and the effect occurs mostly at the nanoscale regime.

Materials with perfect atomic structures and long periodicity are traditionally sought for superlubricity. Carbon compounds such as carbon nanotubes, graphite and graphene are investigated for this purpose. One concern is the difficulty in attaining sustainable superlubricity at the engineering scale.

The structural analysis of graphene wrapped nanodiamonds by Electron energy loss spectra reported in this study are analogous to the previously reported structure of detonated nanodiamonds by other researchers.

Size plays a major role in superlubricity and many researchers have investigated the dependence of size of materials in friction reduction. Liu and co-workers reported one such size dependent study of superlubricity on graphite. They have detailed the probability percentages of superlubric state for different contact areas and also the mechanism of superlubricity (self retraction) of graphite layers.

This is awesome. It's confrontational but also empowering -- definitely keeping her audience in mind.

That's the point. How can one interviewer assume to be more competent than the interviewed or assume to be able to judge objectively some other's work?

Interviewers should start from a place of humbleness and understand they can't spot a person quickly.

Getting to know and trust somebody is a process that requires time; that's true for any kind of human relationship. It can just start with faith, plus a trial period. There's no shortcut that can keep the same judging reliability of a judgment during time.

From the title of the article it's apparent that in the opinion of the author there is need for reviving work ethic in America.

High priority = job and work.

We're at it again friends. This time, as you annotate, concentrate on the moves you see--even if you can't name them--and how they work to produce an effect on you the reader.

Now that GTAs are unionizing, will caps on the amount they can teach continue to drop?

The amount of incoming energy from the sun changes drastically between night and day, and varies throughout the year, yet these variations don't affect Earth's surface temperatures as much as would be expected. Tyndall linked the ability of the atmosphere to absorb infrared radiation (heat) to this dampening of temperature variation.

Interaction of time (tempo/pace) and breakdowns in articulation work.

Evokes Schmidt and Bannon's articulation work in CSCW.

Definition of experimentation.

Describes the use of comment/feedback boxes, ratings, polls, etc. to generate ideas for new coordination workflows, design ideas, workarounds, etc.

Definition of recombinability.

Cites Lessig in describing recombinability "as both a technology design issue and a community governance principle" for reusing/remixing/recombining knowledge

Definition of reviewability.

Faraj et al offer the example of Wikipedia edit log to track changes.

Ways that technology affordances can influence/motivate change in social coordination practices.

Interesting perspective on how technology affordances are a generative response to coordination tensions.

Cites Bowker and Star

Good examples of how boundaries co-evolve and take on new meanings follow this paragraph.

Cites Goffman and the performative vs invisible aspects of social coordination work.

Productive responses to experienced tensions.

Evokes boundary objects (dynamically changing boundaries) and design affordances/heuristics (evolving technology affordances)

Positive consequences: The temporary nature can advance creative uses of the knowledge without hewing to structures, norms or histories of online collaboration.

Negative consequences: Lack of P2P feedback may lead to withdrawal from the group. Pace of knowledge building can be slow and frustrating due to temporary, fleeting convergence dynamics of the group.

Positive consequences: Attention helps to advance the reuse/remix/recombination of knowledge

Negative consequences: "Old-timers" crowd out newcomers

Tension can lead to "unpredictable fluctuations in the collaborative process" such as labor shortages, lack of fresh ideas, in-balance between positive/negative consequences that catalyzes healthy fluidity

Need to consider other possibilities for time/temporal consequences. These examples seem lacking.

Faraj et al identify 5 tensions that have received little attention in the literature (doesn't mean these are the only tensions):

passion, time, socially ambiguous identities, social disembodiment of ideas, and temporary convergence.

Tension as a catalyst for knowledge work/collaboration

Fluidity vs material resources

Evokes LPP

Evokes boundary objects and boundary infrastructures.

Definition of fluidity: "Fluid OCs are ones where boundaries, norms, participants, artifacts, interactions, and foci continually change over time..."

Faraj et al argue that OCs extend the definition of fluid objects in the existing literature.

Motivations include: self-interest, identity, social capital, and social exchange, per org studies researchers.

Strange that Benkler, Kittur, Kraut and others' work is not cited here.

Differences between offline and online knowledge work

Online communities operate with fewer constraints from "social conventions, ownership, and hierarchies." Further, the ability to remix/reuse/recombine information into new, innovative forms of knowledge are easier to generate through collaborative technologies and ICT.

Definition of knowledge work

Definition of online communities

This is an important and relevant point for SBTF/DHN work. Each activation is situated and emergent but there are similarities -- even though the workflows tend to change for reasons unknown.

Cites Orlikowski

Need to think more about how subgroups in SBTF (Core Team/Coords, GIS, locals/diaspora, experienced vols, new vols, etc.) act as communities of practice. How does this influence sensemaking, epistemic decisions, synchronization, contention, negotiation around boundaries, etc.?

Evokes the improvisation of synchronization efforts found in coordination of knowledge work in a pluritemporal setting

More design challenges

The high-tempo, non-routine, highly situated knowledge work of SBTF definitely falls into this category. Design systems/workarounds is challenging.

Differences in boundary work can lead to contentiousness.

Cites Star (boundary objects) and Strauss, Bourdieu (trajectory)

Differences between expertise and dialogic coordination processes.

"1. expertise coordination practices"

"2. dialogic coordination practices"

What would be the SBTF equivalent here?

Faraj and Xiao offer two important points: Context and trajectories "First, the definition emphasizes the temporal unfolding and contextually situated nature of work processes. It recognizes that coordinated actions are enacted within a specific context, among a specific set of actors, and following a history of previous actions and interactions that necessarily constrain future action."

"Second, following Strauss (1993), we emphasize trajectories to describe sequences of actions toward a goal with an emphasis on contingencies and interactions among actors. Trajectories differ from routines in their emphasis on progression toward a goal and attention to deviation from that goal. Routines merely emphasize sequences of steps and, thus, are difficult to specify in work situations characterized by novelty, unpredictability, and ever-changing combinations of tasks, actors, and resources. Trajectories emphasize both the unfolding of action as well as the interactions that shape it. A trajectory-centric view of coordination recognizes the stochastic aspect of unfolding events and the possibility that combinations of inputs or interactions can lead to trajectories with dreadful outcomes—the Apollo 13 “Houston, we have a problem” scenario. In such moments, coordination is more about dealing with the “situation” than about formal organizational arrangements."

Full quote (page break)

"The primary goal is patient stabilization and initiating a treatment trajectory—a temporally unfolding sequence of events, actions, and interactions—aimed at ensuring patient medical recovery"

Knowledge trajectory is a good description of SBTF's work product/goal

Also a good description of digital humanitarian work

Definition and background on practice.

Cites Bourdieu

Complex knowledge work coordination demands attention to how coordination is managed, as well as what (content) and when (temporality).

"This distinction becomes increasingly important in complex knowledge work where there is less reliance on formal structure, interdependence is changing, and work is primarily performed in teams."

Traditional theories of coordination are not entirely relevant to fast-response teams who are more flexible, less formally configured and use more improvised decision making mechanisms.

These more flexible groups also are more multi-disciplinary communities of practice with different epistemic standards, work practices, and contexts.

"Thus, because of differences in perspectives and interests, it becomes necessary to provide support for cross-boundary knowledge transformation (Carlile 2002)."

Evokes boundary objects/boundary infrastructure issues.

Faraj and Xiao contend that coordination practices of fast-response organizations differ from typical groups' structures, decision-making processes and cultures.

1) Expertise is distributed 2) Coordination practices are cross-boundary 3) Knowledge differences are magnified

Summary of paper focus

Evokes Schmidt and Bannon's articulation work

Has this design challege been adequately addressed in CSCW (and CHI, for that matter) in the last 30-ish years?

What role does system meta data (version control, user history, etc.) play in bounding the visibility of decision making?

This also seems to be an area ripe for more collaborative design approaches (participatory, reflective, feminist, etc.)

This seems to still be a major challenge in information system design as well as collaborative workflow. Even if the information/meta context is made available, do people use it?

Ways to better integrate people engaged in distributed work are needed.

Is this still true some 27 years later?

Three particular information quality problems are raised by Schmidt and Bannon:

1) provenance (originator) of the information and his/her/its reliability

2) context of the information

3) politics of the information

This dilemma also applies to the complexity of representing time in information systems.

Source credibility is a complex problem for SBTF. it is not always clear how/why a person on social media has certain information, how they interpret it, and how they summarize it.

This would be good to explore with SBTF in the interviews. Particularly, whether there are different meanings to time modes, time meta data, etc., applied by Core Team, Coordinators, GIS Team, experienced volunteers, new volunteers, etc.

Is this part of the problem with articulating the information extracted from social media and entering it in the Google Sheet in order to become an artifact?

Here Schmidt and Bannon describe the basis for articulation work in a common information space -- which encompasses interactions and breakdowns between information, metaphors, sensemaking, and artifacts.

From a time mode perspective, this gets at what I describe as synchronization.

Pretty much a nutshell of the SBTF time study challenges.

People apply "mechanisms of interaction" to reduce the complexity of the articulation work.

Schmidt and Bannon use these examples:

• Formal and informal organizational structures • Planning and scheduling • Standard operating procedures (see Suchman's work on situated action) • Indexes and classifications for organizational and retrieval (see Bowker and Star on boundary objects/infrastructures)

Schmidt and Bannon posit that organizational models in CSCW should be flexible enough to support new interpretations/evaluations of the model (contingent on circumstances), as well as capture decisions to "adapt, circumvent, execute, modify, etc. the underlying model".

A quick scan of ACM library papers that tag "articulation work" seems to indicate the "common information space" problem still has not attracted a lot of study. This could be a good entry point for my work with CSCW because time cuts across both workflow and information space.

Nicely bundles boundary infrastructure, sense-making and distributed work

Definition of articulation work: "Articulation work arises as a integral part of cooperative work as a set of activities required to manage the distributed nature of cooperative work. In the words of Strauss (1985, p. 8), articulation work is ‘a kind of supra-type of work in any division of labor, done by the various actors’:

Characteristics of cooperative work:

(Taken verbatim from the paper)

• "Cooperative ensembles are either large, or they are embedded within larger ensembles."

• "Cooperative ensembles are often transient formations, emerging to handle a particular situation after which they dissolve again".

• "Membership of cooperative ensembles is not stable and often even non-determinable. Cooperative ensembles typically intersect."

• "The pattern of interaction in cooperative work changes dynamically with the requirements and constraints of the situation."

• "Cooperative work is distributed physically, in time and space."

• "Cooperative work is distributed logically, in terms of control, in the sense that agents are semi-autonomous in their partial work."

• "Cooperative work involves incommensurate perspectives (professions, specialties, work functions, responsibilities) as well as incongruent strategies and discordant motives."

• "There are no omniscient agents in cooperative work in natural settings."

cooperative work arrangements include:

(verbatim from paper) • "augment the mechanical and information processing capacities of human individuals"

• "combine the specialized activities of multiple workers"

• "application of multiple problem solving strategies and heuristics to a given problem"

• "application of multiple perspectives and conceptions on a given problem"

Three many take-aways from cooperative work:

1. It involves people doing work with specific characteristics, e.g., distributed, formed as ensembles, etc.

2. Cooperative work occurs to produce a product or service together because of "technical necessities or economic requirements"

3. is not limited by specific forms of interaction between workers

Circa 1992 this description of CSCW as a design-oriented research area made sense to find some common ground between the CS groupware faction and the org studies, designers, social science, etc. Does this still hold up today?

Definition of CSCW (per Schmidt and Bannon). This is contested.

Schmidt and Bannon argue later (pg 49) that "If CSCW is to be taken seriously, the basic approach of CSCW research should not be descriptive but constructive."

Croll's work made important contributions to the understanding of Earth's climate. However, one problem with his theory was that it led to the conclusion that glacial periods occurred at different times in the Northern and Southern hemispheres.

We now know this is not correct; ice ages are global. But at the time Arrhenius wrote this paper, the geological record of the ice ages was not understood well enough to rule out this possibility of separate glacial periods in the hemispheres.

A study in 2 June 2009 conducted by Philip P. Molloy explored the relations with the age of the marine reserves and of the recovery of different species of fish. The studies showed that older marine reserves (15 years and older) were more effective than younger ones. They harbored more fish.

The open program does this, to an extent. How can this be improved upon?

The speaker regrets her past relationships and realizes they were so meaningless that she does not even remember them. She wishes she could have stayed with the one person she truly did love

The authors recognize the significant achievement and potential of what others have done, but also note the ways in which the previous work can be improved. The goal of this paper is to build upon others' results and to develop new ideas to try to improve upon what has been done.

Is this simply a restatement of the idea that most of "the interesting things" happen at the border or edge of chaos? The Catholic ethic is firmly inside the stable arena while that of the Protestant ethic is pushing the boundaries.

Work around for a design fail

In other words, the customer/user had to make changes (process, use of fields, etc) due to the defects of the design.

neoliberalism and the transformation of knowledge and knowledge work

Proposed framework to address crowdwork management challenges: shared resources, relationships, and crowd labor.

Human computation definition.

This process improvement idea has some interesting design implications for improving temporal qualities of SBTF data: • How is the volunteer thinking about time? • Where does temporality enter into the data collection workflow? • What metadata do they rely on? • What is their temporal sensemaking approach?

Quality control processes is definitely a tension for SBTF.

A better integrated task design and verification process at the end of activations could be more effectively address information quality concerns.

In Kittur's example, synchronous collaboration describes a temporal aspect (timescale and tempo of the work) related to how the collaboration is structured or not.

"Short periods of intense crowd collaboration call for fast teambuilding and may require the automatic assignment of group members to maximize collective intelligence."

Could this be a theme of the SBTF time study?

One aspect of temporality in Kittur's study is related to "realtime" which they describe as the time need to scale up workers and efficiency speed of workers.

The other temporal aspect is synchronicity of workers.

Examples of hierarchical decision-making by both volunteer and paid crowd workers.

Characteristics of complex crowd work.

Later, Kittur refers to complex crowd work as those involving "creativity, brainstorming, essay writing, music composition or civic planning."

Temporality is definitely a work flow issue for SBTF.

However, "realtime" is the only temporal attribute noted in this study but it seems to relate only to completion speed and present/immediacy of tasks.

Research foci

Crowd work processes: Workflow, task assignment, hierarchy, realtime crowd work, synchronous collaboration. quality control

Crowd computation: Crowds guiding AI, AIs guiding crowds, crowdsourcing platforms

Crowd worker future: Job design, reputation/credentials, motivation/rewards

In the literature, quality tends to be used as an attribute of the output (content, HIT, etc.) but could/should it also refer to the crowd worker experience, as Kittur notes: "job satisfaction, direction-setting, coordination, and quality control"?

How are these factors incorporated into the process and incentive system?

time factors in crowd work include speed, scheduling, and sequencing

Crowd work offers flexibility to both workers and requesters to overcome labor shortages, need for expertise, and geographic boundaries.

However, they are very real concerns about exploitation, piecemeal wages, unethical/dubious work, emphasis on speed over quality, and dehumanizing work conditions.

Kittur's definition of crowd work:

"...performance of online tasks by crowd workers who are financially compensated by requesters."

Other early work focused on organizational attributes, like how information goods were produced with flat/informal hierarchies, community values/norms, and governance structures.

Benkler's early work studied "the role of non-exclusive property regimes and more permeable organizational boundaries" for knowledge products.

Maladapative/problematic studies of time include: multitasking, time-switching, presence bleed (work-life convergence), morality, agency and power, individual vs organizational choices, 24/7 availability, etc.

Classic CSWC literature on time includes: groupware calendaring systems, temporal rhythm, temporal trajectories, temporal ordering, temporal artifacts.

With this key phrase of legal discourse, Cuff's takes on the role of a prosecutor in a courtroom, shouldering the burden of proof in the case at hand. What is the relationship between detective work and legal argumentation? How does the novel's language put various characters on trial, not only before other characters, but also before the novel's jury of readers? A word collocation analysis of words and phrases with legal significance would help us to determine whether or not legal language shapes standards of evidence in The Moonstone.

Once again, we encounter the language of detective work, which often involves the uncovering and probing of underlying motives. What distinguishes Betteredge's "detective fever" from Ezra Jennings's understanding of detection? We could operationalize this comparative question into a word collocation study of target words that are associated with detective work (e.g., "detective," "suspect," "motive," etc.).

Vygotsky- social interaction is fundamental in learning- group work is the perfect way to do this- 2 heads are better than one:)

Vocation and avocation again...

Amazing parallel here.

I have a lot of criticisms of the self-occupation link. But this is really interesting connecting self-occupation-community-social contract.

In this study, it was discovered that balsam fir, the island's original dominant tree species, was not able to recruit as it was a favorite food for deer. White spruce, and several companion species, have replaced the fir as deer do not find them palatable.

It was observed that the loss of coyotes as an apex predator control on smaller vertebrate predators, along with habitat fragmentation, led to trophic cascades in the ecosystem.

Predatory sea stars regularly graze the rocky intertidal and are not prey-specific. Their grazing opens new substrate for multiple species, preventing the dominant species from colonizing all of the rocks.

A number of different factors led to the success of the brown tree snake in Guam: barrier-free dispersal, few safe areas for avian prey, lifestyle of the predator (nocturnal and arboreal), and ability of predator to find prey under varying conditions.

A metastudy of 45 replicated and 35 unreplicated field experiments found that introduced predators had double the negative effect than native predators on their vertebrate prey:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1950296/

Researchers found that after wolves were reintroduced to Yellowstone, there was a net decline in soil nitrogen, likely due to fewer large herbivores. In addition, the spatial nature of nitrogen renewal changed due to new use patterns by the herbivores.

Herbivores produce large amounts of methane, a potent greenhouse gas, as a by-product of their diet. By losing so many of these organisms during the Pleistocene and early Holocene, the methane concentration in the atmosphere would have dropped rapidly, helping to cause the global cooling of the Younger-Dryas.

In this case, researchers found that certain types of predatory fish, while consumers of mosquito larvae, also regularly consumed the mosquito's main predators, leading to increased malaria infections.

By allowing the expansion of the predator population (spiny lobster), the prey population size (sea urchins) were held in check and individual urchins suffered from disease less often.

Because of overuse of antibiotics in livestock, the vulture population declined, leading to more scavenging by feral dogs of carcasses throughout the region. As the dog populations grew, and due to their proximity to humans, the risk of transmission of rabies to humans has increased greatly.

In this case, the apex predators have been overhunted by humans for bushmeat, for trophies, or as pests to their livestock.

In a metastudy of 41 papers and 60 independent tests, it was found that terrestrial trophic cascades occurred with more frequently than previously thought across systems and were on par with aquatic environments. While the strength of the cascade response varied across systems based on several factors (type of carnivore, plant antiherbivore defenses, type of damage measured, etc.), trophic cascades were common, although not universal.

To see the effects of one such natural experiment, read: http://science.sciencemag.org/content/294/5548/1923

There have been 5 mass extinctions on Earth in the past. These were caused by various natural events, from gamma-ray bursts to megavolcanic eruptions to meteor strikes. During each mass extinction, species diversity diminished significantly in a short period of time. Each mass extinction was followed by the evolution of novel forms of organisms that transformed their habitats in new ways.

Most scientists agree that we are currently in the 6th mass extinction event, this one largely caused by human activities such as climate change, habitat loss/fragmentation, pollution, invasive species, and human consumption/overexploitation.

In this study, it was noted that ungulates above 150 kg were regularly limited by food availability instead of predation, due to their large body sizes.

Conversely, small ungulates (<150 kg) were regular prey items of the several large carnivores on the Serengeti and their populations, and the trophic levels below them, were controlled by the apex predators.

Loss of predators in these systems caused much greater impacts on the smaller herbivores than the larger ones.

Childers and colleagues demonstrated that Everglades hydrology was co-varying with changes in greenhouse warming potentials, energy fluxes and C dynamics which proved that hydrology is important for creating and maintaining conditions sufficient for wetland ecosystem and structure

Jimenez and colleagues studied the effects of carbon balance in wetland ecosystems before the planned Everglades restoration of historical water flow. They trajected that there would be an alteration on the carbon dynamics of the Everglades as a whole.

Dugan examined wetlands in the United States and the total loss of thus ecosystem. This atlas was able to divide the world’s regions into 19 sections and develop information on the wetlands.

Interesting work on the complex impacts of trophic cascades can be found here: http://science.sciencemag.org/content/314/5801/963

Here: http://science.sciencemag.org/content/277/5325/500

and here: http://science.sciencemag.org/content/315/5820/1846

There are a number of different impacts of humans on the biosphere but loss of apex predators is thought to be one of the widest ranging issues of the planet.

An overview of the threats to the planet's largest 31 carnivores an implications can be found here: http://science.sciencemag.org/content/343/6167/1241484

A person who influences the purchase of a product; they don't only consume it, they convince others to buy it by consuming it themselves. e.g. a you-tuber who is sent clothing, wears that clothing in a video, and then links it in their video as a product for purchase and gets money for it.

Schein, H. (1975). Aspects of the aggressive and sexual behaviour of alpheus heterochaelis say. Marine Behaviour and Physiology, 3(2), 83–96. https://doi.org/10.1080/10236247509378498

This previous work studies aggressive and sexual behavior in snapping shrimp. Although the snapping shrimps studied were found in North Carolina, their behavior reflects the behavior of the genus. Here they established that males seek females using chemical cues, and in general a male with a larger claw/larger body size favors larger females that can produce more offspring. Also, males with larger claws are stronger and can out compete smaller males. In relation to this publication, this previous work establishes a background of the behavior of the snapping shrimp. Understanding their natural behavior helps in understanding how the authors of this publication reached their conclusion. (JP)

Knowlton, N. (1986). Cryptic and Sibling Species among the Decapod Crustacea. Journal of Crustacean Biology, 6(3), 356-363. doi:10.2307/1548175

This previous work defines the term sibling species. According to Knowlton, sibling species are species that have been shown to be very closely related using biochemical techniques such as electrophoretic analysis. Sibling species are not the same species. This publication also uses electrophoretic analyses, known as starch gel electrophoresis, to differentiate between species of snapping shrimp. (JP)

Knowlton, Nancy & Mills, DeEtta. (1992). The Systematic Importance of Color and Color Pattern: Evidence for Complexes of Sibling Species of Snapping Shrimp (Caridea: Alpheidae: AZ'heus) from the Caribbean and Pacific Coasts of Panama. Proceedings of the San Diego Society of Natural History. 18.

This past publication explains how loosely related, or distantly related, species in the genus Afpheus Fabricius (snapping shrimp) can be distinguished based on color morphology such as differences in color patterns. This relates with this publication because both are related to the speciation of snapping shrimp in the Isthmus of Panama. Both publications find methods to differentiate between species; while this paper uses mtDNA and allozymes to compare genetic distance, the other paper uses careful analyses of color patterns to separate species. (JP)

Sexual selection and dimorphism in two demes of a symbiotic, pair-bonding snapping shrimp Knowlton, N. (1980), SEXUAL SELECTION AND DIMORPHISM IN TWO DEMES OF A SYMBIOTIC, PAIR-BONDING SNAPPING SHRIMP. Evolution, 34: 161–173. doi:10.1111/j.1558-5646.1980.tb04802.x

This previous work provides evidence on how differences between mates affects mate choice and, with environmental constraints, can lead to sexual dimorphism which is a distinct difference in size or appearance between the sexes of the same species. This study found that snapping shrimp are very aggressive and territorial to other shrimps of the same sex. By having these type of aggressive traits, compatibility would decrease as species are more separated. This supports one of the results found in this publication. (JP)

Svitil, K.A. (1993). "Oceans Divided". Discover, pp.1-2.

A magazine article by Kathy Svitil talks about the closure of the Isthmus of Panama. She talked about how the rise of Panama 3.5 million years ago separated Atlantic and Pacific species before the land-bridge could even form. This was caused by the shift in tetonic plates, where the Pacific Ocean floor shifted underneath the Carribean plate before melting/solidifying by lava. She states how animals felt the influence of the rifts coming together, even quoting Nancy Knowlton on the speciation of snapping shrimps on either sides of Isthmus since these shrimps used to live in deeper depths of the ocean.

~(J.D.A.)

Knowlton, N. & Keller, B.D. (1982). "Symmetric Fights as a Measure of Escalation Potential in a Symbiotic, Territorial Snapping Shrimp." Behavioral Ecology And Sociobiology, 10(4): 289-292.

This journal goes into detail the behavioral aspect of the Alpheus shrimp. This species readily defends its territory using its large snapping claw. Results gathered focused on symmetric fights of shrimps in regards to sex, size, and resources. According to this study, larger females are more likely to defend their anemone territories and showed more aggressiveness than the male shrimps. The losers of these contests experienced severe injuries by these large females than any other type of shrimps.

~(J.D.A.)

Glynn, P.W. (1985). “El Nino-Associated disturbance to coral reefs and post disturbance mortality by Acanthaster planci.” Marine Ecology Progress Series, 26(17): pp. 295–300.

Another study shows how in 1985 the coral reefs in eastern Pacific (Panama included) got ruined by El Nino due to very high water temperatures (average of 31 Celsius) and depth penetration (over 100 m). Since most habitats in coral reefs were destroyed, many species were easily exposed to predators. This may affect the results obtained by Mills and co. because barely a decade has passed for the marine habitats in Panama to recuperate.

~(J.D.A.)

Read, A., McTeague, J., & Govind, C. (1991). "Morphology and behavior of an unusually flexible thoracic limb in the snapping shrimp, Alpheus heterochelis". The Biological Bulletin, 181(1): pp. 158-168.

This journal explains the morphology of the snapping shrimp Alpheus. Their second thoracic limb is thinner, flexible, bilaterally symmetrical, and possess larger ganglion. This type of limb is almost always active in regards to grooming and foraging for food. The major cheliped, or the larger claw, is used to produce loud popping noises as a defense mechanism against predators.

~(J.D.A.)

Bermingham, E. & Lessios, H.A. (1993). “Rate Variation of Protein and Mitochondrial DNA Evolution as Revealed by Sea Urchins Separated by the Isthmus of Panama.” Proceedings of the National Academy of Sciences, 90(7): pp. 2734–2738.

Another research was made in regards to the closure of Isthmus of Panama 3 MA based on changes in oxygen/carbon ratios in sea water. The main subject studied was sea urchins. Bermingham and Lessios compared mtDNA and protein divergence among three differ species of sea urchins--Diadema, Echinometra, & Eucidaris. Results concluded that protein divergence between Atlantic and Pacific sea urchin species only differed by 1 order of magnitude, so no significant difference. The Diadema species had an overlap of allele frequencies whereas the other two species displayed fixed loci for differ alleles of both shores, which may hint towards gradual genetic drift or mutations.This proves that other marine life besides the Alpheus shrimp community were also affected by a change in the environment via closure of Panama Isthmus.

~(J.D.A.)

Amyloid beta accumulation creates synaptic impairment and learning and memory deficits in AD patients. The impairment of neurons as opposed to neuronal loss maybe the mechanism behind cognitive impairment in AD patients. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3385944/)

Phase amplitude coupling measures the coupling between theta and gamma waves in the hippocampus. The theta and gamma waves are associated with learning and memory. Figure I shows virtually no phase amplitude frequency in the mice with Alz compared to Alz free mice, especially in the APP23p38𝛾-/- mice. Such low frequencies would suggest those mice would have the most problems with learning and memory.

http://www.physiology.org/doi/abs/10.1152/jn.00106.2010

Researchers have found the binding of tau and fyn have been associated with Alzheimer’s disease pathology. Fyn is a kinase that phosphorylates tau and co-localizes with tau in the neurons of Alzheimer’s patients with tau tangles. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4870772/

E. S. Musiek, D. M. Holtzman, Nat. Neurosci. 18, 800–806 (2015). Amyloid-beta is a key initiator of all the downstream processes that cause Alzheimer’s. One process Aβ leads to is initiating tau tangles. Even though Aβ is a key player, Aβ can not cause Alzheimer’s by itself.

K. Iqbal, F. Liu, C.-X. Gong, A del C. Alonso, I. Grundke-Iqbal, Acta Neuropathol. 118, 53–69 (2009). Neurodegeneration from tau implications can be caused from different protein kinases hyperphosphorylating tau. Hyperphosphorylated tau can misfold, create tangles, and not able to stabilize microtubules, all which can all lead to loss of connectivity between neurons.

L. M. Ittner et al., Cell 142, 387–397 (2010)

APP23 mice have increased Aβ toxicity which is the main contributor to the deficits seen in APP23 mice. Deficits include premature death, increased Aβ at young ages, decreased memory, and irregular neuronal circuits.

Hardingham and Bading show that NMDAR responses depend on receptor location. Synaptic NMDARs promotes cell survival, while stimulation of extrasynaptic NMDARs promotes cell death. The unequal stimulation of these receptors cause neuronal dysfunction, while stimulation of synaptic receptors could be used a protective therapy.

In normal physiological conditions tau is used to stabilize microtubular cytoplasmic components in neurons.

APP23 is a version of APP that will develop into AB plaques and aggregates that are associated with Alzheimer’s disease. The APP23 mouse in the experiment overexpressed the APP23 protein.

Previous work: Animals can produce amyloid-beta independently of using APP precursor protein. However, when animals have APP23 mutation, the APP is overexpressed and amyloid beta plaques and intracellular amyloid beta aggregates form. The APP23 has been linked to synapse loss and dendrite degeneration. The APP23 is a Swedish mutation in CNS neurons. (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4046770/ )

Ittner and Gӧtz review new findings showing the interactions of tau and amyloid beta. Tau can shift from the axon to the dendrite helping to increase amyloid beta toxicity.

L. M. Ittner et al., Cell 142, 387–397 (2010).: In this article, Ittner and others show that the absence of tau in amyloid beta-forming mice lessens the severity of amyloid beta toxicity. These results suggest that tau and amyloid beta together increases the symptoms and progression of Alzheimer’s disease.

Beall, C. M. (2007). Two routes to functional adaptation: Tibetan and Andean high-altitude natives. Proceedings of the National Academy of Sciences, 104(Supplement 1), 8655-8660. doi:10.1073/pnas.0701985104

These are some of the physiological traits that were found to be different between populations of Tibetan highlanders and Han Chineese. These include but are not limited to: less oxygen in the arteries, higher breathing rate at rest, loss of low oxygen induced blood vessel constriction, and lower occurrences of decreased birth weight, as well as decreased hemoglobin concentrations.

This paper discusses the effect of gender on hemoglobin levels in Han Chinese and Tibetan Plateau inhabitants as a mechanism for high altitude adaptation. In Han populations a correlation was seen between increased altitude and increased hemoglobin levels (men having higher hemoglobin concentration than women), this correlation was not see in Tibetan highland inhabitants, or between genders of Tibetan highland individuals.

It has been noted that protein divergence increases as divergence time increases, thus being said as time increases more protein divergence occurs. To learn more click here. http://www.pnas.org/content/94/24/13028.full.pdf

• Jake Barbee

S.F. Oberbauer's previous work:

National Science Foundation – Ecosystems. Causes and implications of dry season control of tropical wet forest tree growth at very high water levels: direct vs. indirect limitations (CARBONO - VERANO project).

National Science Foundation – Polar Programs. Arctic Observing Networks: Collaborative Research: Sustaining and amplifying the ITEX AON through automation and increased interdisciplinarity of observations (AON-ITEX).

NSF-Arctic Natural Sciences. Collaborative Research; cold-season gas exchange of arctic plants - resolving winter carbon and water balances of Alaskan arctic tundra (Coldseason project).

NSF -IPY Arctic Observing Networks � Study of Arctic ecosystem changes in the IPY using the International Tundra Experiment. (ITEX-IPY)

DOE-NICCR. Response of carbon dioxide, water, and energy exchange of peat and marl wetlands in the Florida Everglades to changes in hydroperiod (Evergladesflux).

NSF-Biocomplexity. Biocomplexity Associated with the Response of Tundra Carbon Balance to Warming and Drying Across Multiple Scales. Barrowbiocomplexity (this project has sunsetted). Effects of increased season length on plant phenology, community composition, productivity, and ecosystem carbon fluxes in Alaskan tundra Season project (this project has sunsetted)

Carbon stockes and fluxes in a tropical rain forest in Costa Rica Carbono project

NSF- Integrated carbon program. Understanding interannual NEE variability in a tropical rain forest using constrained estimates of carbon exchange. S.F. Oberbauer, D.A. Clark, M. Ryan, D.B. Clark. Carbono-Towers

National Science Foundation - Biocomplexity of the Environment Coupled Biogeochemical Cycles. Complex interactions among water, nutrients and carbon stocks and fluxes across a natural fertility gradient in tropical rain forest. (CICLOS PROJECT).

RW

The way that organisms respond to their environment is ultimately through gene expression. For example, growth is caused by production of growth hormones, among other factors, which are turned on and off. Eukaryotic organisms use histone regulation as one way to respond to environmental changes. It has been found that exchange of histones can occur due to changes in temperature and season, during conflict, movement, learning, and more. AT

H2A.Z.1 is a well documented histone variant. It plays a role in keeping genome integrity, They are highly conserved, even more than H2A.X. AT

Recent research on mollusc DNA has found that they do use methylation systems to regulate their expression. This was determined by using bisulfate PCR. The bisulfate creates a tag on a methylated amino acid in the protein sequence, and PCR is a way to generate many different copies of a single strand of DNA. Using different mapping techniques the locations of methyl group were determined. A methyl group added to a DNA structure serves to wrap the DNA tighter around the histone in order to block transcription. AT

The histone variant H2A.Z Is the most important regarding environmental epigenetic responses. environmental epigenetic are everyday factors in an organism’s life that affect how their genes are expressed that does not create a change in their DNA. AM

H2A.Z was found to have four different subtypes in the Cyprinus carpio, due to the organisms high sense of acclimatization (an individual organisms ability to adjust to a change in its environment such a s a change in altitude, temperature, and humidity). The four subtype variants aid in the thermoregulation (process that allows the body to maintain a core internal temperature) and stability of the organism. KM

H2A.Z.2.2 is found in all human (and some primate species) cell lines but it is found mostly in the brain. It is achieved through alternative splicing of the H2AZ variant. Through biochemical fractionation, the paper results suggest that Z.2.2 causes major structural changes and significantly destabilizes nucleosomes. The findings add to the list of known variants of the H2A.Z family. EM

The papers research clear differences in the structure of the two H2A variants: one in amino acid 38 and one in the structures of the L1 loop. Through mutational analysis, the paper concluded that the amino acid difference at position 38 is partially responsible for the unique functional specializations of H2AZ.1 and H2AZ.2. EM

H2AZ has experienced multiple rounds of specialization which gave rise to new variants. Most vertebrates exhibit the H2AZ.1 and H2AZ.2 variants encoded by independent genes. While their protein products are similar, their promoter regions are very different, suggesting they are each tasked with different roles. The research utilized phylogenetic analysis of the promoter regions to conclude that they evolved separately during vertebrate evolution. EM

They determined that the H2A.Z.1 and H2A.Z.2 are functionally different by individually turning them off and on by knocking out/deleting the gene that codes for the protein. By doing this they discovered that each gene codes for a different protein. Then they discovered that the knockout of each protein resulted in the loss of a distinct function. This work was done in several different studies using different types of cells, such as chicken and human. AT

Highly dynamic chromatin state means that the chromatin is quickly unraveling and raveling to allow transcription, this happens because the histones are rapidly being exchanged from a core to a variant. The variants each give different functions and change the rate of transcription. AM

H2A.Z was derived from H2A through a series of mutations that resulted in it being 60% different from the core H2A. This was determined using a system called GWLA methodology which synthesizes two protein structure determining methods. It breaks the protein into fragments and then sequences it. The H2A.Z is highly conserved throughout eukaryotes meaning that the sequence is the same. Because there are few or no mutations this means that the function is very important and a mutation would be lethal. AT

The family of H2A histone proteins are essential in understanding the biochemistry of chromatin-associated proteins in Mollusca. H2AZ is a variant form of the histone protein that regulates a mediated thermosensory response. The H2A.X variant form contributes to the formation of the nucleosome and its structural integrity.

KM

The papers discuss several structural studies on core histones and linker histone variants. The papers focused on the roles of nucleosome stability, with data showing that histone variability plays an important role in regulation of chromatin metabolism. EM

They determined the structure of histone proteins through crystallography which uses a computer modeling system to determine the atomic structure and how it assembles to form a superhelix model. KM

The author states that it's difficult to examine the exploratory behavior of a free moving fish because the data typically used does not accurately describe the fish's behavior. The EOD geometry and the electric images are complex because they can change based on the fish's movement. The movement changes the source of the electric organs and in laboratory setting the behavior that use electrorepection are hard to maintain preparations for . The difficulty experienced in a control laboratory setting to examine the certain behaviors, makes collecting and analyzing data of a free moving fish ,a challenge .

• Michelle Oriana Gomez-Guevara

In the Drosophila group, members of the Drosophila group have either one or two X chromosomes and two sets of autosomes. Sex determination is determined for females by having balanced female determinants on the X chromosome. For males of the Drosophila group sex determination is based on the determinants on the autosomes. If there is only one X chromosome present in a diploid cell the member of the Drosophila group is male, this is shown by the ratio of (1X:2A). To learn more click here https://www.ncbi.nlm.nih.gov/pubmed/18956315 -Jake Barbee

Heck, K. L. (1977). Comparative species richness, composition, and abundance of invertebrates in Caribbean seagrass (Thalassia testudinum) meadows (Panamá). Marine Biology, 41(4), 335–348. https://doi.org/10.1007/BF00389099

This previous work compares the species composition and abundance of invertebrates in the Caribbean coast of Panama and the Panama Canal Zone. While discussing some factors that could have affected this experiment, the author of this publication noted that the Panama Canal zone could have led to the displacement and death of many snapping shrimp. This previous work observed that species composition of invertebrates (which include snapping shrimp) were the same in tropical and subtropical seagrass meadows, however, different species of shrimp had a lower total abundance. This could mean that the formation of the Isthmus of Panama, followed by the construction of the Panama Canal, had an effect on speciation of several species of shrimp. (JP)

Knowlton, N. (1986). Cryptic and Sibling Species among the Decapod Crustacea. Journal of Crustacean Biology, 6(3), 356-363. doi:10.2307/1548175

This previous work defines the term sibling species. According to Knowlton, sibling species are species that have been shown to be very closely related using biochemical techniques such as electrophoretic analysis. Sibling species are not the same species. This publication also uses electrophoretic analyses, known as starch gel electrophoresis, to differentiate between species of snapping shrimp. (JP)

Schein, H. (1975). Aspects of the aggressive and sexual behaviour of alpheus heterochaelis say. Marine Behaviour and Physiology, 3(2), 83–96. https://doi.org/10.1080/10236247509378498

This previous work studies aggressive and sexual behavior in snapping shrimp. Although the snapping shrimps studied were found in North Carolina, their behavior reflects the behavior of the genus. Here they established that males seek females using chemical cues, and in general a male with a larger claw/larger body size favors larger females that can produce more offspring. Also, males with larger claws are stronger and can out compete smaller males. In relation to this publication, this previous work establishes a background of the behavior of the snapping shrimp. Understanding their natural behavior helps in understanding how the authors of this publication reached their conclusion. (JP)

Sexual selection and dimorphism in two demes of a symbiotic, pair-bonding snapping shrimp Knowlton, N. (1980), SEXUAL SELECTION AND DIMORPHISM IN TWO DEMES OF A SYMBIOTIC, PAIR-BONDING SNAPPING SHRIMP. Evolution, 34: 161–173. doi:10.1111/j.1558-5646.1980.tb04802.x

This previous work provides evidence on how differences between mates affects mate choice and, with environmental constraints, can lead to sexual dimorphism which is a distinct difference in size or appearance between the sexes of the same species. This study found that snapping shrimp are very aggressive and territorial to other shrimps of the same sex. By having these type of aggressive traits, compatibility would decrease as species are more separated. This supports one of the results found in this publication. (JP)

Knowlton, Nancy & Mills, DeEtta. (1992). The Systematic Importance of Color and Color Pattern: Evidence for Complexes of Sibling Species of Snapping Shrimp (Caridea: Alpheidae: AZ'heus) from the Caribbean and Pacific Coasts of Panama. Proceedings of the San Diego Society of Natural History. 18.

This past publication explains how loosely related, or distantly related, species in the genus Afpheus Fabricius (snapping shrimp) can be distinguished based on color morphology such as differences in color patterns. This relates with this publication because both are related to the speciation of snapping shrimp in the Isthmus of Panama. Both publications find methods to differentiate between species; while this paper uses mtDNA and allozymes to compare genetic distance, the other paper uses careful analyses of color patterns to separate species. (JP)

Bermingham, E. & Lessios, H.A. (1993). “Rate Variation of Protein and Mitochondrial DNA Evolution as Revealed by Sea Urchins Separated by the Isthmus of Panama.” Proceedings of the National Academy of Sciences, 90(7): pp. 2734–2738.

Another research was made in regards to the closure of Isthmus of Panama 3 MA based on changes in oxygen/carbon ratios in sea water. The main subject studied was sea urchins. Bermingham and Lessios compared mtDNA and protein divergence among three differ species of sea urchins--Diadema, Echinometra, & Eucidaris. Results concluded that protein divergence between Atlantic and Pacific sea urchin species only differed by 1 order of magnitude, so no significant difference. The Diadema species had an overlap of allele frequencies whereas the other two species displayed fixed loci for differ alleles of both shores, which may hint towards gradual genetic drift or mutations.This proves that other marine life besides the Alpheus shrimp community were also affected by a change in the environment via closure of Panama Isthmus.

~(J.D.A.)

Read, A., McTeague, J., & Govind, C. (1991). "Morphology and behavior of an unusually flexible thoracic limb in the snapping shrimp, Alpheus heterochelis". The Biological Bulletin, 181(1): pp. 158-168.

This journal explains the morphology of the snapping shrimp Alpheus. Their second thoracic limb is thinner, flexible, bilaterally symmetrical, and possess larger ganglion. This type of limb is almost always active in regards to grooming and foraging for food. The major cheliped, or the larger claw, is used to produce loud popping noises as a defense mechanism against predators.

~(J.D.A.)

Knowlton, N. & Keller, B.D. (1982). "Symmetric Fights as a Measure of Escalation Potential in a Symbiotic, Territorial Snapping Shrimp." Behavioral Ecology And Sociobiology, 10(4): 289-292.

This journal goes into detail the behavioral aspect of the Alpheus shrimp. This species readily defends its territory using its large snapping claw. Results gathered focused on symmetric fights of shrimps in regards to sex, size, and resources. According to this study, larger females are more likely to defend their anemone territories and showed more aggressiveness than the male shrimps. The losers of these contests experienced severe injuries by these large females than any other type of shrimps.

~(J.D.A.)

Svitil, K.A. (1993). "Oceans Divided". Discover, pp.1-2.

A magazine article by Kathy Svitil talks about the closure of the Isthmus of Panama. She talked about how the rise of Panama 3.5 million years ago separated Atlantic and Pacific species before the land-bridge could even form. This was caused by the shift in tetonic plates, where the Pacific Ocean floor shifted underneath the Carribean plate before melting/solidifying by lava. She states how animals felt the influence of the rifts coming together, even quoting Nancy Knowlton on the speciation of snapping shrimps on either sides of Isthmus since these shrimps used to live in deeper depths of the ocean.

~(J.D.A.)

Glynn, P.W. (1985). “El Nino-Associated disturbance to coral reefs and post disturbance mortality by Acanthaster planci.” Marine Ecology Progress Series, 26(17): pp. 295–300.

Another study shows how in 1985 the coral reefs in eastern Pacific (Panama included) got ruined by El Nino due to very high water temperatures (average of 31 Celsius) and depth penetration (over 100 m). Since most habitats in coral reefs were destroyed, many species were easily exposed to predators. This may affect the results obtained by Mills and co. because barely a decade has passed for the marine habitats in Panama to recuperate.

~(J.D.A.)

Sox10 is expressed in melanoblasts, which are the precursors of melanocytes, that do not contain Ednrb. Ednrb is expressed in embryos that do not contain Sox10. Therefore, Sox10 expression does not depend on the expression of Ednrb. (DB)

Studies show that there is a high expression of VEGF in human melanoma tumors, indicating that VEGF can serve as a marker for melanoma prognosis. Moreover, tumors with a high vascular density (VD) were also associated with poor prognosis. (DB)

Exposure to ultraviolet (UV) radiation is a risk factor for the development of melanoma. Researchers have shown that people who sunburned in childhood are at a greater risk of developing melanoma than are people who sunburned in adulthood. This study suggests that age is associated with the susceptibility of skin to environmental carcinogens. (DB)

There is an increase in the amount of Ednrb in most cell lines. This is significant because Ednrb expression is increased in melanoma metastases. (DB)

Ednrb encodes a G-protein-coupled receptor that is necessary for the development of melanocytes. Studies have shown that Ednrb is not necessary for the development of early melanoblasts but is essential for the expression of the differentiation marker tyrosinase. Ednrb wild-type cultures must be able to generate the KIT ligand. Moreover, a soluble KIT ligand allows tyrosinase to be expressed in cultures that do not contain sufficient amounts of Ednrb. (DB)

Mutations in genes that code for Edn3 result in deficiencies in melanocytes. Edn3 serves as a stimulator of melanoblast proliferation and differentiation. When melanoblasts differentiate, they become melanocytes. (DB)

Researchers have shown that individual melanocytes produce multipotent cells that are able to regenerate during consecutive subcloning. This indicates that the multipotent cells display stem cell qualities. Edn3 encourages the maintenance of the multipotent cells. Moreover, Edn3 stimulates the proliferation of melanoblasts, which are the precursors of melanocytes. (DB)

Cells proliferate in the presence of Edn3. The cells that are produced are melanoblasts, which subsequently become melanocytes. (DB)

Researchers isolated Edn1 to determine its function. Edn1 was shown to be responsible for an increase in blood pressure. Expression of the gene was controlled by factors that affect blood vessels, suggesting that there is a cardiovascular control system. (DB)

A study in 2 June 2009 conducted by Philip P. Molloy explored the relations with the age of the marine reserves and of the recovery of different species of fish. The studies showed that older marine reserves (15 years and older) were more effective than younger ones. They harbored more fish.

Our social work education accrediting organization fetishizes competencies, thereby inducing stress in instructors, which then gets passed along to the students. I use hypothes.is extensively and can directly observe the students transition from coping to engagement.

Step 1 in any process: decide how you are going to make decisions.