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Justin's Linklog Posts

Links for 2021-03-23

Published March 23, 2021

  • The impact of population-wide rapid antigen testing on SARS-CoV-2 prevalence in Slovakia | Science

    Well done, Slovakia — massive decrease in prevalence after 2 rounds of mass testing.

    Slovakia conducted multiple rounds of population-wide rapid antigen testing for SARS-CoV-2 in late 2020, combined with a period of additional contact restrictions. Observed prevalence decreased by 58% (95% CI: 57-58%) within one week in the 45 counties that were subject to two rounds of mass testing, an estimate that remained robust when adjusting for multiple potential confounders. Adjusting for epidemic growth of 4.4% (1.1-6.9%) per day preceding the mass testing campaign, the estimated decrease in prevalence compared to a scenario of unmitigated growth was 70% (67-73%). Modelling indicated that this decrease could not be explained solely by infection control measures, but required the additional impact of isolation and quarantine of household members of those testing positive.

    (tags: testing slovakia via:luke-oneill covid-19 screening mass-testing)

Links for 2021-03-18

Published March 18, 2021

Links for 2021-03-16

Published March 16, 2021

  • Chicken Story

    ‘tl;dr: The time when Microsoft banned my entire country for cheating at Club Bing.’ This is a great story — though it must have been driving the MS Asirra anti-abuse team up the wall. Quite interesting to hear about low-cost/grassroots ways to accomplish some of the tech tasks, e.g. instead of firing up a farm of EC2 instances to crack a Captcha, he farmed out that work using thumbdrives, manually distributed to his friends.

    (tags: coding asirra microsoft club-bing bing cheating usb-drives)

Links for 2021-03-12

Published March 12, 2021

Links for 2021-03-10

Published March 10, 2021

  • The human footprints of Ojo Guareña | CENIEH

    Amazing well-preserved human footprints from between 4200 and 4600 years ago:

    The Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) has participated in chapter 17, which covers the prints of bare feet preserved in the soft floor sediment of Palomera Cave in the Ojo Guareña Karst Complex (Merindad de Sotoscueva, Burgos, Spain). These footprints, ascribed to traces left by about ten individuals who explored the caves between 4200 and 4600 years ago, were discovered in 1969 by Grupo Espeleológico Edelweiss (GEE) at the Sala y Galerías de las Huellas site, some 1200 m from the entrance to Palomera Cave. The fragility of the footprints and their environment meant it was not possible to study them, and doing so has had to await the development of the new non-invasive teledetection techniques.

    (tags: footprints history humans prehistory archaeology spain)

Links for 2021-03-04

Published March 4, 2021

Links for 2021-02-26

Published February 26, 2021

  • How Competitive Matchmaking and Rating Works In Overwatch

    Reverse-engineered by an external user, it seems: ‘This information below is gathered from sporadic developer posts and videos, salted with my own experience and experiments, various forum threads, and watching streams. Note that since Blizzard does not give exact algorithms, I do have to fill in some gaps, or leave some items unknown.’ The matchmaking systems are very complex and a key component of what makes games like Overwatch playable, so this is interesting stuff. (via Shevaun)

    (tags: matchmaking overwatch gaming games pvp player-rating)

Links for 2021-02-24

Published February 24, 2021

  • Amulet version 1

    This is great. An amulet is ‘a kind of poem that depends on language, code, and luck. To qualify, a poem must satisfy these criteria: Its complete Unicode text is 64 bytes or less; and the hexadecimal SHA-256 hash of the text includes four or more 8s in a row.’

    The hash is a cold hexadecimal spew – 9a120001cc88888363fc67c45f2c52447ae64808d497ec9d699dba0d74d72aab – and, like a fingerprint, it doesn’t tell you anything about the entity it identifies. That’s by design, but even so, it feels strange for a value so pivotal to be totally disconnected from the underlying content, especially when it is this value that’s being collected and traded in cryptographic marketplaces. Ostensibly, the hash provides an immutable link between unique cryptographic object and free-floating digital media. The amulet asks: what if we took that link seriously? In a sense, the definition of the SHA-256 hash function created, at a stroke, all amulets of all rarities. Common to mythic, trashy to lovely, they have been hiding in the manifold combinations of language; we just didn’t know we ought to be looking for them. Until now!

    (tags: poetry blockchain amulets poems sha-256 crypto)

Links for 2021-02-22

Published February 22, 2021

Links for 2021-02-19

Published February 19, 2021

  • Facebook knew for years ad reach estimates were based on ‘wrong data’ but blocked fixes over revenue impact, per court filing | TechCrunch

    Via Colman Reilly — this really sounds like outright fraudulent behaviour by FB:

    The filing also reveals that a Facebook product manager for the “potential reach” tool warned the company was making revenue it “should never have” off of “wrong data”. The unsealed documents pertain to a U.S. class action lawsuit, filed in 2018, which alleges that Facebook deceived advertisers by knowingly including fake and duplicate accounts in a “potential reach” metric. Facebook denies the claim but has acknowledged accuracy issues with the “potential reach” metric as far back as 2016 — and also changed how it worked in 2019. […] Redacted documents from the lawsuit, reported by the WSJ last year, included the awkward detail that a Facebook employee had asked “how long can we get away with the reach overestimation?”

    (tags: fraud facebook ads ad-fraud bots revenue metrics via:colman)

Links for 2021-02-17

Published February 17, 2021

  • UK ONS data showing school transmission of COVID-19

    This is pretty solid real-world data, IMO — even if they’re not testing correctly to find it, it’s there in the ONS data

    (tags: ons uk covid-19 schools education)

  • ‘Classic triad’ of symptoms misses positive COVID-19 cases, study finds

    Testing people with any of the three ‘classic’ symptoms would have spotted 69% of symptomatic cases, with 46 people testing negative for every person testing positive. However, testing people with any of seven key symptoms – cough, fever, anosmia, fatigue, headache, sore throat and diarrhoea – in the first three days of illness would have detected 96% of symptomatic cases. In this case, for every person with the disease identified, 95 would test negative. Researchers also found users of the Symptom Study App were more likely to select headache and diarrhoea within the first three days of symptoms, and fever during the first seven days, which reflects different timings of symptoms in the disease course. Data from the ZOE app shows that 31% of people who are ill with COVID-19 don’t have any of the triad of symptoms in the early stages of the disease when most infectious.

    (tags: covid-19 symptoms medicine diseases)

Links for 2021-02-13

Published February 13, 2021

Links for 2021-02-09

Published February 9, 2021

Links for 2021-02-08

Published February 8, 2021

  • Variants v. Vaccines – Tomas Pueyo

    Excellent article from Tomas Pueyo on the new COVID-19 variants:

    In the race between the variants and the vaccines, the variants are the hare and the vaccines are the tortoise. We all know that, in the end, the vaccines will win. Like the tortoise. By this summer, in developed countries, vaccination rates will likely range between 50% and 80%. Since there will also be some herd immunity, and summer means outdoors in the Northern hemisphere, it’s likely that the pandemic will die down some time during the summer. The question is: Will they also be rolled out in time to prevent the new variants from taking over? Now we have our answer: Unfortunately, no.
    TBH, though, I am not so sanguine about the results for the Northern hemisphere. With open borders, no mandatory quarantine, and the rest of the world suffering without sufficient access to vaccines, new variants will keep passaging and keep emerging, risking putting our vaccine progress back to square one. (via Cormac)

    (tags: tomas-pueyo virology covid-19 sars-cov-2 variants vaccines herd-immunity via:cormac)

Links for 2021-02-04

Published February 4, 2021

Links for 2021-02-01

Published February 1, 2021

Links for 2021-01-28

Published January 28, 2021

  • Brazil coronavirus variant crushes Manaus – The Washington Post

    Jaysus, this is terrifying.

    Galvão, the lead physician in the coronavirus ward at a public hospital in the Brazilian city of Manaus, had been haunted by the wave that crashed last spring. In less than 10 days, it ruptured the city’s bewildered medical system. Sick patients were turned away. The dead were piled into mass graves. So Galvão’s hospital organized contingency plans. Additional beds were reserved, and a detailed schedule for opening them was created. But the new surge, when it came, was different. The virus had mutated, with a suite of alterations that probably made it more transmissible — and perhaps more lethal. Manaus was hit by what scientists call the P.1 variant. This time, it didn’t take 10 days to overwhelm Galvão’s hospital. It took 24 hours.

    (tags: p.1 variants covid-19 manaus brazil medicine)

  • pascalw/kindle-dash: Power efficient dashboard for Kindle 4 NT devices

    oh my, I didn’t realise you could jailbreak a Kindle and do this! Simple dashboard that HTTP fetches a rendered PNG periodically and refreshes the Kindle screen with it

    (tags: e-ink kindle jailbreak hacks dashboards e-paper)

Links for 2021-01-26

Published January 26, 2021

Links for 2021-01-25

Published January 25, 2021

  • Badger Seal (Mask Fitter)

    What is a mask fitter? A soft, flexible and adjustable “frame” that significantly improves the outer seal of a mask. Why use it? Adding the Badger Seal to a 3-ply disposable mask reduces the effective particle penetration by typically 15x (see the Performance section below). What makes the Badger Seal unique? It’s cheap (< $1 in materials), easy to assemble, made from readily available materials and tools, comfortable, quickly customizable and open source. There are other fitters out there, though none seem to excel in all of these areas.

    (tags: masks diy covid-19 badger-seal facemasks aerosols transmission makers)

Links for 2021-01-20

Published January 20, 2021

  • Association between survival rates in intensive care and the level of ICU occupancy on the day of admission

    Recent preprint paper from the UK —

    Adjusting for patient-level factors, mortality was higher for admissions during periods of high occupancy (>85% occupancy versus the baseline of 45 to 85%) [OR 1.19 (95% posterior credible interval (PCI): 1.00 to 1.44)]. In contrast, mortality was decreased for admissions during periods of low occupancy (<45% relative to the baseline) [OR 0.75 (95% PCI: 0.62 to 0.89)]. [...] The results of this study suggest that survival rates for patients with COVID-19 in intensive care settings appears to deteriorate as the occupancy of (surge capacity) beds compatible with mechanical ventilation (a proxy for operational pressure), increases. Moreover, this risk doesn’t occur above a specific threshold, but rather appears linear; whereby going from 0% occupancy to 100% occupancy increases risk of mortality by 92% [...]
    As Andrew Kunzmann noted – “To aid interpretation, the difference in risk for a 70-year-old man with no comorbidities being admitted during a period of high versus low occupancy is equivalent to the risk if they were approximately a decade older”.

    (tags: risk icu hospitals covid-19 pandemics medicine papers preprints mortality)

  • 6-month consequences of COVID-19 in patients discharged from hospital: a cohort study – The Lancet

    A recent preprint from China — lots of “long COVID” impact, still:

    Fatigue or muscle weakness (63%, 1038 of 1655) and sleep difficulties (26%, 437 of 1655) were the most common symptoms. Anxiety or depression was reported among 23% (367 of 1617) of patients. The proportions of median 6-min walking distance less than the lower limit of the normal range were 24% for those at severity scale 3, 22% for severity scale 4, and 29% for severity scale 5–6.

    (tags: covid-19 long-covid china preprints papers)

Links for 2021-01-18

Published January 18, 2021

Links for 2021-01-14

Published January 14, 2021

  • Seasonality of Respiratory Viral Infections | Annual Review of Virology

    tl;dr: temperature, humidity, vitamin D are all important:

    The seasonal cycle of respiratory viral diseases has been widely recognized for thousands of years, as annual epidemics of the common cold and influenza disease hit the human population like clockwork in the winter season in temperate regions. Moreover, epidemics caused by viruses such as severe acute respiratory syndrome coronavirus (SARS-CoV) and the newly emerging SARS-CoV-2 occur during the winter months. The mechanisms underlying the seasonal nature of respiratory viral infections have been examined and debated for many years. The two major contributing factors are the changes in environmental parameters and human behavior. Studies have revealed the effect of temperature and humidity on respiratory virus stability and transmission rates. More recent research highlights the importance of the environmental factors, especially temperature and humidity, in modulating host intrinsic, innate, and adaptive immune responses to viral infections in the respiratory tract. Here we review evidence of how outdoor and indoor climates are linked to the seasonality of viral respiratory infections. We further discuss determinants of host response in the seasonality of respiratory viruses by highlighting recent studies in the field.

    (tags: infection viruses colds flu covid-19 seasonality diseases)

Links for 2021-01-13

Published January 13, 2021

  • 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)

Links for 2021-01-11

Published January 11, 2021

Links for 2021-01-10

Published January 10, 2021

  • 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)

Links for 2021-01-08

Published January 8, 2021

Links for 2021-01-07

Published January 7, 2021

  • 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)

Links for 2021-01-06

Published January 6, 2021

Links for 2020-12-31

Published December 31, 2020

  • 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)

Links for 2020-12-28

Published December 28, 2020

  • 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)

Links for 2020-12-23

Published December 23, 2020

  • “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)

Links for 2020-12-17

Published December 17, 2020

  • 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)