22 Matching Annotations
  1. May 2021
    1. If she goes offline, we may still be able to get the same photo from Grace or another peer.

      this is interesting: so we actually do want some amount of duplication and redundancy. i wonder if it is enough to assume that some of this is going to happen, or whether we want to also incentivize or make it happen in some way.

    2. hashes can prevent malicious actors from deceiving us about the content of files

      a very specific sense of trust. i wonder how this might be generalized, if at all. this is a form of proof.

    3. trust the information that's shared

      in a specific sense, i think, namely that the "location" actually contains the thing it says it has.

    4. Cryptographic hashes can be derived from the content of the data itself, meaning that anyone using the same algorithm on the same data will arrive at the same hash. If Ada and Grace are both using the same decentralized web protocol, such as IPFS, to share the exact same photo of a kitten, both images will have exactly the same hash. By comparing those hashes and confirming that they're the same, we can guarantee that every single pixel of those two photos is identical.

      I wonder whether this is all or nothing, or whether there is any room for fuzzy / approximate matching. Could hashes derived from "similar" data (e.g., picture of the same kitten, but from a slightly different angle) be "similar" in some sense?

  2. Apr 2021
    1. Last year the futurist Ayesha Khanna even described smart contact lenses that could make homeless people disappear from view

      Worth noting that this description was in the context of a warning against the temptation of "deletive reality": https://www.ayeshakhanna.com/blog/welcome-to-the-hybrid-age

  3. Jan 2021
    1. building theories of capacities is a daunting task. The space of possible theories is, prima facie, at least as large as the space of effects: For any finite set of (naturalistic or controlled) observations about capacities, there exist (in principle) infinitely many theories consistent with those observations. However, we argue that theories may be built by following a constructive strategy and meeting key plausibility constraints to rule out from the start theories that are least likely to be true: We refer to this as the theoretical cycle

      effective synthesis is hard.

      here they offer strategies for dealing with this difficulty. note here that plausibility constraints are empirical!

    1. PredicTER is a tool for estimating how long a review will take to complete. The tool calculates the time requirements for various tasks involved in reviewing evidence, from planning and coordination to quantitative synthesis and reporting.  The tool contains default values provided by an assessment of 5 years of systematic reviews and maps published by the Collaboration for Environmental Evidence, but users can tailor the tool based on what they know about their own subject.

      estimates based on 5 years of experience with systematic reviews/maps at Collaboration for Environmental Evidence (but details of the estimation approach aren't known here)

  4. Dec 2020
    1. Clusters of infections within families living in Bnei Brak were identified and investigated. The parents were asked regarding the first case of the infection in the family and regarding the pre-sumed source of the infection.In addition, household members underwent polymerase chain reaction (PCR) testing whether they were symptomatic or not

      testing regime: exhaustive (whether symptomatic or not)

    2. Thirteen family clusters were investigated; all families reside in the city of Bnei Brak.

      N=13 families

    3. Mayenei Hayeshuah Medical center is located in the city of Bnei Brak, Central Israel.Bnei Brak is a “young” city. Children of 0–19 years of age comprise almost 50% of its 200,000 population, and the average number of children in a family is 4.57

      setting: central Israel

    4. SARS-CoV-2 positive PCR was documented in the different age groups as follows:1. In 21 of 36 adults (>18 years) (58.3%).2. In 13 of 40 children, 5–17 years (32.5%), (P = 0.037 for the difference between group 1 and group 2, risk ratio: 0.61, 95% confidence interval [CI]: 0.39–0.96).3. In 2 of 18 children, 0–4 (<5) years of age (11.8%), (P < 0.002 for the difference between group 1 and group 3, risk ratio: 0.47, 95% CI: 0.30–0.71)

      main result: children ~half as likely to get infected given equivalent exposure in same household

  5. Nov 2020
    1. young children in particular are approximately half as likely as adults to acquire the infection given equivalent exposure.

      Current belief on children's susceptibility to COVID

  6. Sep 2020
    1. While so much about the virus and how it operates remains unclear, sub-Saharan Africa so far has dodged a deadly wave of coronavirus cases. Many factors have contributed to this. A number of West African nations already had a pandemic response infrastructure in place from the Ebola outbreak of late 2013 to 2016. Just six years ago, Liberia lost nearly 5,000 people to Ebola. At the beginning of this year, Liberia began screening for covid-19 at airports. Travelers coming in from countries with more than 200 cases were quarantined. To date, Liberia, a country of some 5 million, has 1,335 cases and around 82 deaths.

      example-of the importance of [[infrastructure]]

  7. Jul 2020
    1. in the unexposed patients, 40 to 60% had CD4+ cells that already respond to the new coronavirus

      cross-reactivity of cd4+ t-cell responses from previous coronaviruses?

    2. 100% of the exposed patients had CD4+ cells that responded to all three of these. There were also significant CD4+ responses to other viral proteins: nsp3, nsp4, ORF3s, ORF7a, nsp12 and ORF8

      good cd4+ t-cell responses in COVID patients

    1. The difference between detecting COVID antibodies and detecting T cells with an effective anti-COVID response is kind of like the difference between detecting guns and detecting assassins. One of these is relatively straightforward; the other one requires extensive investigation.

      Good analogy to explain why it's hard to detect (and therefore study) T cells

    1. just because antibodies in plasma wane over time doesn’t mean that individual’s aren’t protected right, Derek? What’s really important is Memory B-Cells, which can rapidly reproduce antibodies if the antigen is seen again? Have peoeple tested individuals with SARS-CoV-2 for Memory B-Cell formations?

      memory B cells are important, even if antibodies are gone, can produce antibodies again quite quickly if needed

    2. BUT there is a hidden assumption, an artefact of the initial model’s simplified reality assumptions, the Susceptible and Recovered must be randomly spread out. This randomisation is the mechanism that extinguishes the virus (in the model !). In observable reality, these two populations are not perfectly intermixed.

      herd immunity works differently for vaccination scenarios vs. population infection, due to distribution of susceptible vs. recovered (near random / equitable with vaccination, systematically nonrandom with population infection)

    3. antigen specific memory B cells themselves–by definition fairly low abundance and difficult to distinguish from standard B cells using assays robust enough to handle large numbers of samples.

      memory B cells are important to immune responses, but can be hard to detect reliably at scale

    4. There are hundreds of viruses that can cause common cold symptons. Endemic coronaviruses, enteroviruses, rhinoviruses, coxsackie viruses, parainfluenza – probably a bunch that are unknown at this point.

      common cold is caused by many other kinds of viruses, not just coronaviruses

    5. Highly conserved sections of the virus are also often highly protected. Look at the effort that’s been put into the universal influenza vaccine. The parts that are stable enough to dependably target are also usually hidden, and only revealed briefly when the virus activates.

      reasons to doubt that targeting aspects of viruses that are "conserved" (i.e., remain stable across mutations / strains) is a viable strategy for a vaccine

  8. Feb 2020
    1. “I can imagine a scenario where this becomes a fifth endemic human coronavirus,” said Stephen Morse of Columbia University’s Mailman School of Public Health, an epidemiologist and expert on emerging infectious diseases. “We don’t pay much attention to them because they’re so mundane,” especially compared to seasonal flu.

      Can imagine != likely == possible