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Justin Mason's Weblog Posts

Links for 2021-01-13

  • Endemic SARS-CoV-2 will maintain post-pandemic immunity

    This article in _Nature Reviews Immunology_ suggests that “SARS-CoV-2 is likely to become the fifth endemic common cold virus, causing largely asymptomatic infections.”

    Endemic SARS-CoV-2 will ensure maintenance of seroprevalence and mucosal immunity in the population, which will increase over time in new generations. As such, most infected individuals will ultimately endure a largely asymptomatic or mild course of disease, although similarly to the other common cold HCoVs, SARS-CoV-2 may cause fatalities in extremely vulnerable elderly or immunocompromised individuals. SARS-CoV-2 mutants will arise as already reported, but new variants will unlikely differ sufficiently to escape established immunity. Cross-reactive immunity, critically boosted by natural reinfections, should conserve good levels of population protection also against new variants, thereby preventing the occurrence of severe disease, including in the vulnerable. Therefore, we predict that the need for large-scale vaccination programmes will be transient until an endemic state for SARS-CoV-2 is reached.

    (tags: sars-cov-2 covid-19 diseases immunology nature)

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Links for 2021-01-11

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Links for 2021-01-10

  • Derctuo

    Kragen’s followup to Dercuano:

    a book of notes on various topics, mostly science and engineering with some math, from the first year of the COVID-19 pandemic, 02020 CE.  Its primary published form is a gzipped tarball of 9MB of HTML files and sources, although there’s also an inferior PDF version of about 1000 pages for reading on hand computers or printing. It uses a page size slightly smaller than standard for improved readability on hand computers. [….] It contains some novel discoveries, but some of it is just my notes from exploring the enormous feast of knowledge now available on the internet to anyone who takes the time to taste of it, and some other parts are explorations that didn’t pan out — left here only as a cautionary tale to the next explorer. There are lots of notes in here that aren’t “finished” in the usual sense; they end in the middle of a sentence, or say “XXX”, or have a note in them that the foregoing is wrong in such-and-such a way.  But I am publishing the final version of Derctuo today.  I might make future versions of some of these notes, but not of Derctuo itself.

    (tags: derctuo kragen notes books reading essays)

  • A large scale analysis of hundreds of in-memory cache clusters at Twitter | USENIX

    Modern web services use in-memory caching extensively to increase throughput and reduce latency. There have been several workload analyses of production systems that have fueled research in improving the effectiveness of in-memory caching systems. However, the coverage is still sparse considering the wide spectrum of industrial cache use cases. In this work, we significantly further the understanding of real-world cache workloads by collecting production traces from 153 in-memory cache clusters at Twitter, sifting through over 80 TB of data, and sometimes interpreting the workloads in the context of the business logic behind them. We perform a comprehensive analysis to characterize cache workloads based on traffic pattern, time-to-live (TTL), popularity distribution, and size distribution. A fine-grained view of different workloads uncover the diversity of use cases: many are far more write-heavy or more skewed than previously shown and some display unique temporal patterns. We also observe that TTL is an important and sometimes defining parameter of cache working sets. Our simulations show that ideal replacement strategy in production caches can be surprising, for example, FIFO works the best for a large number of workloads.

    (tags: caching memcached memory twitter usenix via:marc-brooker)

  • Is there a tool that tells you which IAM actions to allow if you give it an API operation? : aws

    ‘For example, say I want to allow an IAM role to aws s3 sync to a given S3 bucket. Is there a tool that will tell me the list of actions to permit on the bucket, if I input that command to the tool?’ tl;dr: nope there is not. Good list of links to related tools to ameliorate the IAM shitfest though

    (tags: iam aws permissions security apis)

  • The PHIA probability yardstick

    the UK government’s official terminology to clearly describe the probability of events occurring, ranging from “REMOTE CHANCE” to “ALMOST CERTAIN”

    (tags: chance probability terminology words uk phia odds)

  • Mason, Thomas Holmes (1877-1958)

    My illustrious great-grandfather:

    Mason was a keen cyclist; his tours through the Irish countryside as a youth, as well as his interest in photography from the age of twelve (he would take over 20,000 pictures by his death), led him to the study of the natural world and Irish archaeology. This culminated in his publication of The islands of Ireland: their scenery, people, life and antiquities (1936), visually recording the minutiae of Irish folk life and the natural beauty of the island landscapes. Mason did not restrict his interests to any one discipline and was involved in a multifarious range of organisations: member of the Dublin Field Club, one-time president of the Irish Society for the Protection of Birds, member of the Dublin Zoological Council (serving as honorary vice-president from 1952), member and president (1926) of the Photography Society of Ireland, member of the Geographical Society of Ireland, and member of the National Monuments Council as well as president (1951) of An Taisce. He was also president of the Dublin Mercantile Association (1923) and the Dublin Rotary Club and a fellow of the RSAI. He was elected MRIA (1931) and contributed numerous articles to the Academy’s Transactions and Proceedings on subjects ranging from the history of the optical profession in Dublin to Celtic archaeology. Mason provided meteorological information to Irish newspapers from his home observatory at 39 Kenilworth Square before the establishment of the Irish meteorological service (1936). His other interests included Irish moths as well as Irish lantern slides, on which he published Catalogue of photographic lantern slides of Irish scenery and antiquities [n.d.] and Catalogue of lantern slides of Irish antiquities (1928). Mason was the seventh member of his family to be made an honorary freeman of the city of Dublin (29 April 1903), one of the last such hereditary appointments. His wife Margaret Evelyn, whom he married c.1909, was a fellow presbyterian. Three of his four sons succeeded him in the family business, which celebrated its bicentenary in 1980 and traded into the third millennium. He died on 12 February 1958, leaving his library to the Old Dublin Society and TCD.

    (tags: family thomas-mason history ireland archaeology photography)

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Links for 2021-01-08

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Links for 2021-01-07

  • Practical tips for if you test positive for COVID-19

    good video from MedCram (“Evidence based updates on COVID-19 and CME for clinicians.”) — I don’t need it — yet — but bookmarking just in case…

    Practical tips from Dr. Seheult if you test positive for COVID-19: – Use of a pulse oximeter at home; – Who gets monoclonals? – Immune boosting vitamins: D, NAC, C, Quercetin, Zinc; – The data on sleep (& melatonin); – Data on core temp. elevation (Sauna etc)

    (tags: medcram medicine covid-19 treatment immunity)

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Links for 2021-01-06

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Links for 2020-12-31

  • Derek Lowe on the UK authorities’ plan to spread out the two doses of the Pfizer/BioNTech vaccine

    ‘The UK government is thus running a real-time experiment on its population in the hopes that the benefits of a first dose of its available vaccines (AZ/Oxford, Pfizer/BioNTech) will outweigh the risks of then messing with the dosing schedule. The horrible part is that there’s a good case to be made that running this big experiment (and taking on the risk of lowering the overall effect of the two-dose schedule) is still the right decision. Things are bad. But don’t pretend it’s not an experiment, or that we know what the outcome will be. This is a desperation move, and it’s a terrible thing that such a strategy has made it to the top of the list. I hope it works.’

    (tags: vaccines vaccination covid-19 uk dosing)

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Links for 2020-12-28

  • I’m a consultant in infectious diseases. ‘Long Covid’ is anything but a mild illness | Long Covid | The Guardian

    With the excitement of the Covid vaccine’s arrival, it may be easy to forget and ignore those of us with “long Covid”, who are struggling to reclaim our previous, pre-viral lives and continue to live with debilitating symptoms. Even when the NHS has managed the herculean task of vaccinating the nation, Covid-19 and the new mutant variants of the virus will continue to circulate, leaving more people at risk of long Covid. Data from a King’s College London study in September suggested as many as 60,000 people in the UK could be affected, but the latest statistics from the Office for National Statistics suggest it could be much higher.
    (via Shane Dempsey)

    (tags: via:sdempsey long-covid covid-19 health medicine)

  • Characterizing Long COVID in an International Cohort: 7 Months of Symptoms and Their Impact | medRxiv

    ‘From a cohort of 3762 Long COVID respondents, probability of symptoms lasting >35 weeks was 91.8%’; ‘Most frequent lingering symptoms reported after 6 months were: fatigue 77.7%, post-exertional malaise* 72.2% and cognitive dysfunction 55.4%.’

    (tags: long-covid covid-19 health medicine papers)

  • The carbon footprint sham

    BP created the concept of a ‘carbon footprint’ as a devious, manipulative PR tactic:

    A few years after BP began promoting the “carbon footprint,” MIT researchers calculated the carbon emissions for “a homeless person who ate in soup kitchens and slept in homeless shelters” in the U.S. That destitute individual will still indirectly emit some 8.5 tons of carbon dioxide each year. “Even a homeless person living in a fossil fuel powered society has an unsustainably high carbon footprint,” said Stanford’s Franta. “As long as fossil fuels are the basis for the energy system, you could never have a sustainable carbon footprint. You simply can’t do it.”

    (tags: carbon co2 bp emissions climate-change pr)

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Links for 2020-12-23

  • “Glutamate plumes” as a potential origin for migraines

    Mice that get migraines have helped scientists in the US to uncover what might be going on in the more than 10 per cent of us who suffer from the condition. What K.C. Brennan at the University of Utah has done is to make a genetic change in his mice, so they mimic the make-up of one group of humans who suffer regular migraines. By watching the brains of these animals, they’ve found that, periodically, surges appear of an excitatory nerve signal called glutamate. This, they speculate, causes overstimulation of the nearby nerve cells, starting the neurological equivalent of a Mexican wave that ripples across the brain. As it does so, it activates pain pathways that cause the ensuing headache.

    (tags: glutamate neurotransmitters neurology brains health medicine mice migraines headaches)

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Links for 2020-12-17

  • Rocky Flats

    Absolutely bananas Twitter thread — it is frankly miraculous that they didn’t have multiple criticality incidents on their hands. TIL about “infinity rooms”:

    ‘They made plutonium “pits” for nuclear bombs, either from new plutonium sources or reprocess parts of old bombs, from 1957 until 1988. In 1988, the EPA investigated the site, shrieked in horror, and shut the place down. the DOE stuck their fingers in their ears and went LA LA LA DON’T WANNA DEAL WITH IT for about five years afterward, but finally started cleanup in ’94. Among the tasks: cleaning 13 “infinity rooms” – areas so radioactive that plant instruments went off the scale, and were just sealed in place. One had been welded shut and abandoned as far back as ’72. One had been piled full of contaminated equipment and filled with concrete. US Gov: your task is finding the 1,100 pounds of plutonium that somehow became lost in ductwork, drums and industrial gloveboxes. The amount of missing plutonium at Rocky Flats is enough to build 150 Nagasaki strength bombs. “Occasionally you’d feel a drip on your head and you’d be contaminated with plutonium nitrate,” DeMaiori said.”‘

    (tags: infinity-rooms horror military-industrial-complex us-politics nuclear nuclear-weapons plutonium environment history bombs epa doe)

  • How to Send SMS Messages with Google Sheets and your Android Phone – Digital Inspiration

    Particularly impressive demo of MIT AppInventor, which lets you build an Android app with block-based GUI programming

    (tags: appinventor apps android mit coding blocks gui sms google-sheets texting)

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Links for 2020-12-16

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Links for 2020-12-14

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Links for 2020-12-09

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Links for 2020-12-08

  • Amazon, Amex to Fund Software Developers in New GitHub Program – Bloomberg

    ‘ Inc., American Express Co., Daimler AG and Stripe Inc. are among those joining a new GitHub program that will let companies directly fund open-source projects and software developers that are key to their businesses.’ interesting

    (tags: github funding open-source oss work software)

  • Ventilation | CDC

    This is significant — the CDC is _finally_ detailing mitigation strategies against airborne SARS-CoV-2.

    When indoors, ventilation mitigation strategies help to offset the absence of natural wind and reduce the concentration of viral particles in the indoor air. The lower the concentration, the less likely some of those viral particles can be inhaled into your lungs; contact your eyes, nose, and mouth; or fall out of the air to accumulate on surfaces. Protective ventilation practices and interventions can reduce the airborne concentration, which reduces the overall viral dose to occupants. Below is a list of ventilation interventions that can help reduce the concentration of virus particles in the air, such as SARS-CoV-2. They represent a list of “tools in the mitigation toolbox,” each of which can be effective on their own.  Implementing multiple tools at the same time is consistent with CDC mitigation strategies and increases overall effectiveness. These ventilation interventions can reduce the risk of exposure to the virus and reduce the spread of disease, but they will not eliminate risk completely.

    (tags: covid-19 advice cdc best-practices ventilation air air-quality sars-cov-2)

  • dropbox/setsum

    Via Robert Escriva – ‘the set-based checksum algorithm we made. Add items in any order and still get the same checksum. Union two independently created sets and get the same result as having done it as one iteration.’

    (tags: checksums hashing dropbox sums summarising algorithms streaming)

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Links for 2020-12-04

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Links for 2020-12-03

  • Hammerspoon

    ‘a tool for powerful automation of OS X. At its core, Hammerspoon is just a bridge between the operating system and a Lua scripting engine. What gives Hammerspoon its power is a set of extensions that expose specific pieces of system functionality, to the user. You can write Lua code that interacts with OS X APIs for applications, windows, mouse pointers, filesystem objects, audio devices, batteries, screens, low-level keyboard/mouse events, clipboards, location services, wifi, and more.’ (via Tony Finch)

    (tags: via:fanf automation osx mac lua scripting hammerspoon)

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Links for 2020-12-01

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Links for 2020-11-26

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Links for 2020-11-25

  • Gnome launched into space in a real-life reenactment of a Half Life 2 achievement

    A new achievement called “Gnome Alone” was added to [Half-Life 2: Episode Two, Half-Life: Alyx, and Left 4 Dead 2], and the description sums up exactly what’s going on. “If you are reading this achievement, Gabe Newell has successfully launched Gnome Chompski into space. If you did not also receive the achievement ‘Manufacturing Ascent’, Newell has abandoned his plans to shoot Noam Chomsky into space.” …There’s an Amelie-inspired achievement for picking up the gnome at the start of [Half Life 2: Episode Two] and bringing it all the way to the rocket at White Forest Base, an arduous task involving lots of item juggling and repeated cramming of the gnome into a crevice in Episode Two’s muscle car. Similar challenges made their way into Alyx and Left 4 Dead 2 as well.

    (tags: garden-gnomes gnomes funny noam-chomsky achievements games half-life history gabe-newell rockets space)

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Links for 2020-11-24

  • Home Assistant Data Science

    Great feature:

    The Home Assistant Data Science portal is your one stop shop to get started exploring the data of your home. We will teach you about the data that Home Assistant tracks for you and we’ll get you up and running with Jupyter Lab, a data science environment, to explore your own data.

    (tags: docs data home-assistant iot data-science graphs o11y home han)

  • Excel error causes 1,500 deaths

    Excerpted from _Does contact tracing work? Quasi-experimental evidence from an Excel error in England_: ‘we find 120,000 COVID-19 cases & 1,500 deaths linked to those cases that were not referred to contact tracing in time. This represents ~20% of all new COVID19 cases [in England] during weeks 39-44.’ Twitter thread:

    (tags: excel fail public-health contact-tracing england nhs covid-19 deaths papers)

  • misleading reliance on pointing to “household transmission” for COVID-19 in Ireland

    This article is a perfect example. It’s headlined: “Virus spread: How a single household transmission led to 46 Covid-19 cases”

    A team of public health specialists in the midlands traced how a case of household transmission led to 26 cases of Covid-19 in a manufacturing plant and a further 20 cases in other households, a nursing home and a school. The first case, or “index case” they became aware of was a woman who worked in a manufacturing plant. Household transmission of the virus occurred when a person she was living with, who had acquired Covid in a pub, passed the virus to her.
    So in other words — the true index case was the person in the pub, or at the very least, her housemate who picked up COVID-19 in the pub, and this was a case where the pub was the initial cluster location, leading to 47 further cases. But for some reason, the article chooses “household transmission” as the headline…

    (tags: pubs restaurants covid-19 safety epidemiology ireland contact-tracing public-health households transmission)

  • What Facebook Fed the Baby Boomers – The New York Times

    The feed goes on like this — an infinite scroll of content without context. Touching family moments are interspersed with Bible quotes that look like Hallmark cards, hyperpartisan fearmongering and conspiratorial misinformation. Mr. Young’s news feed is, in a word, a nightmare. I know because I spent the last three weeks living inside it.

    (tags: grim-meathook-future facebook newsfeed america nytimes)

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Links for 2020-11-24

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Links for 2020-11-19

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Links for 2020-11-18

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Links for 2020-11-16

  • OSHA issues ventilation guidance to workplaces for airborne SARS-CoV-2

    OSHA issues ventilation guidance to workplaces for airborne #SARSCoV2: – HVAC systems should be fully functional; – Prevent personal fans from blowing air from one worker to another; – Use HVAC filters w/MERV rating 13 or higher; – Increase HVAC’s outdoor air intake; – Open windows/sources of fresh air; – Be sure exhaust air isn’t pulled back into the building from HVAC air intakes or open windows; – Use portable HEPA fan/filtration to increase clean air; – Restrooms fans should operate max capacity, and remain on.
    These are all eminently sensible. Now to see if anything equivalent happens on this side of the pond.

    (tags: aerosols covid-19 airborne diseases sars-cov-2 transmission air fans hvac air-conditioning workplaces work)

  • Can’t open apps on macOS: an OCSP disaster waiting to happen | CryptoHack Blog

    Finally, a good take on Apple’s OCSP crapfest over the past weekend.

    If Apple’s OCSP check was built to soft-fail [which is apparently the case], then why did apps hang when the OCSP Responder was down? Probably because this was actually a different failure case: the OCSP Responder was not completely down, it was performing badly. Due to the load added by millions of users worldwide upgrading to macOS “Big Sur”, Apple’s servers slowed to a crawl, and although they weren’t properly answering OCSP queries, they were working just enough that the soft-fail didn’t trigger.
    IMO — this is a big fail by Apple. Network callouts to perform OCSP checks on app startup are a critical case where a Hystrix-level infrastructure of timeouts and short-circuits were appropriate to fail safely in as many situations as possible. The article goes on:
    By adding several mundane failure modes to the verification process, OCSP spoils any cryptographic elegance the code signing and verifying process has. While OCSP is also widely used for TLS certificates on the internet, the large number of PKI certificate authorities and relaxed attitude of browsers means that failures are less catastrophic. Moreover, people are accustomed to seeing websites become unavailable from time to time, but they don’t expect the same from apps on their own devices. macOS users were alarmed at how their apps could become collateral damage for an infrastructure issue at Apple. Yet this was an inevitable outcome arising from the fact that certificate verification depends on external infrastructure, and no infrastructure is 100% reliable. Scott Helme also has concerns about the power that Certificate Authorities gain when certification revocation actually works effectively. Even if you aren’t bothered about the potential for censorship, there will be occasional mistakes and these must be weighed against the security benefits. As one developer discovered when Apple mistakenly revoked his certificate, the risk of working within a locked down platform is that you may get locked out.

    (tags: apple ocsp fail fail-safe hystrix osx macos)

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Links for 2020-11-13

  • Risk Assessment and Management of COVID-19 Among Travelers Arriving at Designated U.S. Airports, January 17–September 13, 2020 | MMWR

    MMWR from the CDC on passenger entry screening at US airports (via Anthony Staines):

    Passenger entry screening was resource-intensive with low yield of laboratory-diagnosed COVID-19 cases (one case per 85,000 travelers screened). Contact information was missing for a substantial proportion of screened travelers in the absence of manual data collection. What are the implications for public health practice? Symptom-based screening programs are ineffective because of the nonspecific clinical presentation of COVID-19 and asymptomatic cases. Reducing COVID-19 importation has transitioned to enhancing communication with travelers to promote recommended preventive measures, strengthening response capacity at ports of entry, and encouraging predeparture and postarrival testing. Collection of contact information from international air passengers before arrival would facilitate timely postarrival management when indicated.

    (tags: screening travel air air-travel airports via:astaines cdc mmwr covid-19)

  • Inky Impression

    Wow, this looks spectacular!

    5.7″, 600 x 448 pixel 7 colour electronic paper (ePaper / eInk / EPD) display for Raspberry Pi. plenty of screen real estate for text or graphics. The low power consumption e-paper display is crisp and readable in bright sunlight and the image will persist when unpowered. In a first for the Inky series, we’ve also added four tactile buttons on the back, so you can control what’s on the screen without the need for extra hardware. But the best bit is that this time you get seven whole colours to play with, which means this Inky is very suitable for displaying graphics, drawings or art – we’ve found pixel art, panels from comics and retro video game art look particularly good.

    (tags: e-ink displays raspberry-pi hacking video devices e-paper)

  • Charles proxy for web scraping

    wow, Charles is nifty. must give it a go next time I’m scraping something

    (tags: scraping mitm charles web http proxies web-scraping automation)

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Links for 2020-11-13

  • Risk Assessment and Management of COVID-19 Among Travelers Arriving at Designated U.S. Airports, January 17–September 13, 2020 | MMWR

    MMWR from the CDC on passenger entry screening at US airports (via Anthony Staines):

    Passenger entry screening was resource-intensive with low yield of laboratory-diagnosed COVID-19 cases (one case per 85,000 travelers screened). Contact information was missing for a substantial proportion of screened travelers in the absence of manual data collection. What are the implications for public health practice? Symptom-based screening programs are ineffective because of the nonspecific clinical presentation of COVID-19 and asymptomatic cases. Reducing COVID-19 importation has transitioned to enhancing communication with travelers to promote recommended preventive measures, strengthening response capacity at ports of entry, and encouraging predeparture and postarrival testing. Collection of contact information from international air passengers before arrival would facilitate timely postarrival management when indicated.

    (tags: screening travel air air-travel airports via:astaines cdc mmwr covid-19)

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Links for 2020-11-12

  • Covid Winter is Coming. Could Humidifiers Help? | WIRED

    Add humidity to the list:

    after three months of data crunching, they found that the most powerful correlation between national numbers of daily new coronavirus cases and daily Covid-19 deaths was indoor relative humidity. Even controlling for dozens of other factors, the data showed that as indoor relative humidity went up during the summer months in the northern hemisphere, deaths plummeted. In the southern hemisphere, the opposite was true—as humidity fell during those nations’ winter months, deaths began to climb. “It’s so powerful, it’s crazy,” says [Stephanie] Taylor. That work has not yet been published. But Taylor believes it’s the strongest evidence yet that humidity needs to be as much a part of the conversation about containing Covid-19 as is discussion of ventilation, masks, and hand hygiene. “It’s hard to prioritize one intervention over another; we need all of them,” says Taylor. “Humidifiers aren’t a replacement for masks or social distancing or ventilation. But when you have more humidification, it enhances all these other things we’re already doing.” At higher humidities, respiratory particles grow faster and fall to the ground earlier, so there’s a better chance that staying 6 feet apart from infectious people really will dilute how many bits of their aerosolized virus you might happen to inhale. In a recent modeling study, Japanese researchers found that air with 30 percent relative humidity can carry more than twice the number of infectious aerosols, compared to air with relative humidity levels of 60 percent or higher. That also means masks are more likely to block more of the particles coming out of people’s noses and mouths, because they tend to be better at trapping bigger particles than smaller ones. And it means that air purifiers (even cheap, DIY ones) will filter out a larger proportion of potentially infectious particles.

    (tags: covid-19 aerosols humidity humidifiers air air-quality health infection)

  • 50 beautiful Irish crafts to buy, and the people who make them

    so many good things here

    (tags: crafts art ireland irish gifts xmas)

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Links for 2020-11-09

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Links for 2020-11-09

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Links for 2020-11-03

  • COVID-19 IFR is estimated at 0.97%

    Florian Krammer on Twitter: “Our NYC serosurvey paper is now out in Nature: if extrapolated to the NYC population we found [more than] 1.7 million infected and IFR at 0.97” That’s high! Nearly 1 in 100.

    (tags: ifr covid-19 florian-krammer mortality deaths pandemics)

  • Fault in NHS Covid app meant thousands at risk did not quarantine

    Somebody, somewhere, will have died needlessly due to this bug.

    The root of the error, the Guardian has learned, was a decision to incorporate a measure of “infectiousness” into the app’s code. While the app was undergoing testing in the Isle of Wight, it used a simple metric that recommended isolation for anyone who had been in contact – closer than 2 metres – with a potentially infectious person for 15 minutes or more in a single day. But shortly before the app was launched nationally, it was updated to account for the fact that people are most infectious shortly after their symptoms show. The maths was changed so that people outside that period of peak infectiousness counted for just two-fifths of the risk. Since that meant the overall score was likely to be lower, the intention was to reduce the risk threshold correspondingly to ensure that someone of maximum infectiousness would need just three minutes of contact before they triggered an alert. But that change never happened, and as a result, users were only told to isolate if they had spent 15 minutes close to a very infectious person, or nearly 40 minutes near someone who was pre-symptomatic but still thought to be shedding the virus. The error was only discovered when a new version of the contact-tracing app, which can better account for exposures at mid-range (over a metre away) was created. The unfeasibly high risk score also explained another problem plaguing the app: “ghost notifications” warning users that they may have been exposed to someone with Covid, but which never resulted in advice to isolate. The app’s initial advice to users was that these notifications could be safely ignored, since they reflected a contact below the risk threshold; now that the NHS risk threshold is known to have been artificially low, one insider said, it is likely that the vast majority of those ghost notifications should in fact have been advice to self-isolate.

    (tags: bluetooth nhs bugs failure ble covid-19 uk)

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Links for 2020-11-02

  • I Lived Through Collapse. America Is Already There. | by Indi Samarajiva

    In the last three months America has lost more people than Sri Lanka lost in 30 years of civil war. If this isn’t collapse, then the word has no meaning. You probably still think of Sri Lanka as a shithole, though the war ended over a decade ago and we’re (relatively) fine. Then what does that make you? America has fallen. You need to look up, at the people you’re used to looking down on. We’re trying to tell you something. I have lived through collapse and you’re already there. Until you understand this, you only have further to fall.

    (tags: collapse usa politics columbo sri-lanka history civil-war)

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Links for 2020-10-27

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Links for 2020-10-23

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