Arhiiv kuude lõikes: May 2020

Metsavendlus oleks tänapäevase tehnoloogia vastu edutu

Infrapunakaameratega droonid ja luurelennukid avastaksid metsast inimesesuurused soojad objektid, eriti talvel lehtedeta puude vahelt ja lume taustal. Veel lihtsam oleks lõket avastada, kuna temperatuurikontrast ümbrusega on suurem, nii et talvel oleks metsavendadel valik külmunud toidu ja oma asukoha äraandmise vahel. Isegi maa-aluses punkris tuld tehes peab sooja suitsu kusagile välja laskma, mis infrapunakaameraga näha on. Kui suits välisõhu temperatuurile jahutada, siis on selle tihedus ka välisõhuga sama, nii et see ei tõuse enam ülespoole.

Maastikul liikuva inimkeha soojust on raske varjata, sest ennast soojusisolatsioonimaterjali sisse mähkides läheb palavaks. Võibolla kivivillast ja hõbepaberist vihmavari aitaks vältida ülespoole kiirgavat soojust, aga see vihmavari võib mõnel teisel elektromagnetilise spektri osal näha olla.

Masinõppimine suurelt valimilt aero- ja satelliidifotodelt aitaks loodusest inimtegevuse jälgi tuvastada. Seda valimit tehisintellekti treenimiseks saab tekitada, käskides paljudel väikestel sõdurirühmadel Venemaa avarustes varjatud laagreid ja punkreid ehitada, preemiatega parimatele varjajatele. Siis pildistada õhust neid teadaolevatel koordinaatidel laagreid ja negatiivse kontrollgrupina laagrivaba loodust, lasta arvutil klassifitseerida, kumb on kumb ja seeläbi õppida, mis tunnused tegelikku laagrit tavalisest loodusest eristavad.

USA ebaedu Afganistanis tuleb demokraatliku riigi soovimatusest liiga palju tsiviilelanikke tappa – õhust võib küll tuvastada looduses liikuvad inimesed, aga vaenlase võitlejate eristamine neutraalsetest karjustest on keeruline. Mägisel maastikul pole ka õhust kõik punktid vaadeldavad, näiteks rada eenduva kaljuserva all.

Ka Nõukogude Liit ei tahtnud Afganistani liiga inimtühjaks teha, sest soovis jätta muljet, et on seal afgaanide kutsel sõbralikult kommunismi ehitamas. Lenin või Stalin oleks Afganistanis võitnud oma tavalise taktikaga: küüditada liiga palju vastu hakkavate piirkondade inimesed Siberisse. Tänapäeval saaks geriljasid maha suruda ka vähemdrastiliste vahenditega – keelata loata looduses viibimine, ettekäändeks näiteks maastikupõlengute ennetamine või looduskaitse, siis tuvastada õhust looduses viibijad, jälitada drooniga neid koduni või punkrini ja nad kas kodus arreteerida või punkris droonirünnakuga tappa. Afganistani koopad on õhulöökidele üsna vastupidavad, nii et seal peaks maastikul hulkuvad inimesed enne koobast neutraliseerima. Kodus istuv rahvas jääks enamasti puutumata, mis suurendaks motivatsiooni asulas püsida. Seevastu valimatu tapmine või küüditamine paneks inimesed vastu hakkama põhimõttel „surm siin või Siberis”.

Eesti-taolisel tasasel maal on mägede analoogiks linnad: katuseserva all kõndijad on õhust raskestinähtavad, hoonete sisemused on nagu koopad paljude sissepääsudega. Võitlejate eristamine linnaelanikest on keeruline. Selleks oleks vaja tuvastada, kes kannab kaasas tulirelvakujulisi metallobjekte, aga need saaks maskeerida metallkarkudeks, järelveetava kohvri käepidemeks, jalgrattaraamiks jne. Lennujaamastiilis metallidetektorväravad tänavatel oleksid üsna kulukad ja neist saaks läbi majade, aedade ja kanalisatsiooni ümber liikuda.

Tissue sampling by piggybacking on vaccination or testing campaigns

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Obtaining tissue samples from a large population of healthy individuals is useful for many research and testing applications. Establishing the distribution of genes, transcriptomes, cell distributions and morpologies in a normal population allows comparing clinical laboratory findings to reference values obtained from this baseline. The genetic composition of the population can be used to estimate historical migration patterns in paleoanthropology and selective pressures in evolutionary biology.

Gathering tissue samples from many people is expensive and time-consuming, unless it happens as a byproduct of existing programs. Collecting used vaccination needles or coronavirus nasal swabs that have a few cells attached allows anonymous tissue sampling of almost the entire population. A few cells per person are enough for many analyses in modern biology. Bulk collection of needles or swabs has built-in untraceability of biological material to an individual, which should alleviate privacy concerns and reduce the bureaucratic burden of ethics approvals.

Flight cameras for environmental and traffic monitoring

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Recordings from the downward-pointing cameras on commercial airliners that provide inflight belly-cam views could be downloaded after landing to use for research, for example on vegetation cover, traffic density on roads, night-time light which measures economic development. The flight paths are saved on flight tracking websites anyway, which enables localising the video at any point of time to the GPS coordinates the flight was at. The recordings are not much use for military spying because countries ban overflights of sensitive sites anyway. Thus security and privacy arguments should not stop research in this case.

The resolution of the belly cameras is low and the wavelengths cover only visible light, not infrared which would be useful for vegetation measurements. The compensating upside is the frequent overflights of many parts of the globe, thus the dense temporal coverage. The videos are almost costless to obtain – just plug an external hard drive into the existing inflight entertainment system to and later upload its contents at the airport. The low cost contrasts with specialised satellite and aerial surveys.

Algae tattooed for doping and oxygen administration

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The paper by Qiao et al. (2020) in Science Advances shows that unicellular algae injected near a hypoxic tumour photosynthesise oxygen in the body in response to infrared light with wavelength 660nm that penetrates >4mm into tissues. The oxygen saturation of the tumour rises from 6.2% to 30% in 2 hours after the algae receive a 5-minute laser exposure. The oxygen sensitises the tumour to radiation therapy. No side effects were found from the algae in this or previous research. The performance of the algae stayed the same when these were coated with red blood cell membranes to delay their clearance from the body.

Another application of algae that can produce oxygen in the organism is doping in sports. The algae can be tattooed under skin that is exposed to light containing enough of the wavelengths which the algae use and which can penetrate under the skin. For example, long-distance runners outdoors in warm weather have most of their skin exposed to sunlight, thus have a large surface area suitable for algal oxygen production. The additional oxygen from photosynthesis improves athletic performance. The only question is whether the oxygen generation is quantitatively fast enough to make a difference. In elite sports, every little advantage counts, so athletes are probably willing to use algae tattoos.

The algae are not dangerous even in deep blood vessels and tissues. Eventually the organism clears the algae, but the clearance of foreign particles is slower in the skin than in deep tissues, as evidenced by the persistence of ordinary tattoos. So the algae will last for a daylong competition.

Patients with breathing problems, for example with coronavirus-induced lung inflammation, may also benefit from algae tattooed on a large area of skin which is then illuminated with 660nm light. Such oxygen supplementation reduces the need for mechanical ventilation. Again, the question is the amount of oxygen from a whole-body algal tattoo.

Clock and ads projected on the ceiling

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At a public swimming pool, the clocks on the wall are usually small, far and hard to see through droplet-covered goggles. The clock is relevant for planning to finish by a certain time and for tracking one’s speed (lap time). A solution is to use a projector to show a large clock on the ceiling, or to draw the numbers on the ceiling with a laser – essentially a programmed pointer.

The ceiling is also an untapped advertising display space, not just at swimming pools and gyms, but in any building. Ceiling ads are more valuable in swimming pools, gyms and yoga studios than in most other structures, because people doing backstroke, bench press or fish pose are facing the ceiling, which is not the case in a majority of buildings.

The floor is also mostly unused ad space. Projecting ads on the floor is not as useful as the ceiling, because people walking through the projector beam block the display.

Spordiriiete higihaisu vältimisest

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Spordiriided on enamasti polüestrist või nailonist, mida ei tohiks väga kuumalt ega valgendajaga pesta. Tavalise pesuga ei tule higihais päris maha kui higi on riietel juba kuivanud ja paar päeva seisnud kuni pesumasinatäis koguneb. Pesule allumatu higilõhna ennetamiseks tasub riided läbi loputada enne kui higi neil kuivab. Seda on lihtne teha, võttes riided pärast trenni duši alla kaasa. Seal põrandal vedeledes ligunevad need enamvähem läbi ja pärast saab need näiteks dušiotsiku külge kuivama riputada kuni enam ei tilgu.

Veel niiskena loputamine võib ennetada ka kaenlaaluseid higiplekke, mis tavalises pesus maha ei tule. Sama kehtib vereplekkide kohta mitmesugustest kriimustustest, jalgratta pealt kukkumisest jne – kui riided näiteks haava pestes kraanikaussi või duši alla ligunema panna, siis veri ei hüübi riietele ja plekid ei kinnistu.

Food refused by the most people

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Which food would the greatest fraction of the world population refuse to eat? To make the question interesting, focus on widespread food items, not „interesting” local specialties like surstromming, fermented shark, maggot cheese. My guess is that pork and beef would be the most widely refused, by Muslims and Hindus respectively. Meat in general is considered objectionable by more people than vegan dishes. Refusal of plant-based food is mostly due to allergies, so soy and wheat would be the least popular. In light of this, it is interesting that the main components of the British Airways snack box on 17 May 2020 were made of wheat and pork (Jamon Iberico and a spread made of 57% bacon and 18% pork jowl). The box replaced the usual airline meal. According to British Airways, the reason was to reduce food heating on the plane during the Covid-19 pandemic. I am not sure how reducing cooking is supposed to avoid infection, but even supposing that, the pork-based snacks do not seem optimal by any criterion.

Vegan food is generally cheaper, and among animal-source foods, chicken is the cheapest, followed by turkey. So price cannot be the reason for serving pork. Airlines may try to signal wealth or that they care about passengers by offering „premium” foods, e.g. meat, and not the cheapest kind. However, this signal is undermined by the plastic boxes for the meals, the sloppy mixture of foods in the main box and the small quantities. The goal is clearly not to feed people or to keep them healthy. It does not seem reasonable for the airline to expect that it will give passengers a good taste experience.

Exercise is better than working to buy health insurance

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Health insurance does not insure health, but wealth. Exercising to prevent disease is often better than working to buy health insurance to cover treating that disease. For example, cancer, stroke and cardiovascular disease predominantly occur in old age, so insurance against these is highly substitutable with exercise.

The American Association for Critical Illness Insurance in 2011 listed the following average annual premiums by age group for a male nonsmoker based on a $40,000 benefit for treatment of cancer, stroke or heart attack. Age 40: $575 to $610; age 45: $745 to $785; age 50: $940 to $980. Similar premiums in 2019 only buy cancer insurance.

At an after-tax hourly wage of $20, paying these premiums requires 30-50 work hours per year, about 0.6-1 hour per week, or 0.6-1% of waking hours. From a baseline of zero sports, one hour per week of exercise increases lifespan by one year, or by about 1/80 of life expectancy. Whether switching an hour per week from work to exercise (and cutting health insurance to compensate for the lost hourly wage) is a good investment in terms of lifespan depends on how much treatment lengthens life and how much health insurance increases the probability or quality of treatment. Data is difficult to find on both the effect of treatment on lifespan and the effect of health insurance on treatment.

The median survival rate to hospital discharge after EMS-treated out-of-hospital cardiac arrest with any first recorded rhythm is 7.9%. So for serious heart conditions, treatment and thus health insurance does not make much difference. Lung cancer treatment is said to prolong survival by about three months, which also seems small. Even if no health insurance implies no treatment, which is not the case because emergency care is still provided, investing worktime to buy health insurance seems to have a low benefit. People with cancer survive with a probability about 2/3 of the survival probability of a comparable population without cancer, so the upper bound on the benefit of treatment is 2/3 times the probability of getting cancer times the remaining life expectancy. This upper bound is loose, because zero treatment does not reduce the 5-year survival probability to zero.

Preventing overeating by advance cooking

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A commitment device that prevents overeating is to only buy food that needs cooking (raw meat or fish, dry goods such as rice, flour, beans), and only buy drinks with zero calories. After each meal, measure out the ingredients for the next meal. The ingredients may be put into a pressure cooker, slow cooker, microwave or other gadget with a timer to cook, so the food is ready at the next mealtime, but not before. This procedure leaves no ready-to-eat food to snack on between mealtimes and no option to eat a larger portion than planned. The reason to portion out the next meal right after the previous meal is to do it while not hungry, thereby preventing oneself from increasing the portion size.

Sufficiently fast food delivery breaks the commitment, because it permits ordering a snack that arrives before the next mealtime. Such delivered food is typically processed and unhealthy. Vending machines, convenience stores, takeout restaurants or other sources of ready food in or near the building also weaken the commitment. Quarantine strengthens the commitment, reducing the temptation to go out seeking food.

Eating a balanced diet is more difficult when restricting food to only categories that need significant preparation time. Fruits and most vegetables can be eaten raw and juices give quick calories due to their high glycaemic index. Frozen fruits and vegetables are more difficult to snack on immediately, thus ease commitment without compromising health. Frozen fruit juice concentrate similarly delays gratification for at least a few minutes. Small berries thaw very quickly in water, so are a temptation.

Lifehacks to prevent overeating (from Youtube): eat in front of a mirror, avoid distractions like a computer, TV or smartphone while eating, use small dishes (Japanese style).

Riiete voldid peaksid olema tahapoole suunatud

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Sissevõtuvoltidega (plisseeritud) pükstel on voldid suunatud tahapoole (eesmised voldid külgede suunas), mis on hea, sest edasisuunas liikudes ei jää sellised voldid asjade taha kinni. Samal põhjusel peaksid lõõtstaskute voldid olema taha suunatud, aga olen näinud ja kandnud ette suunatud voltidega lõõtstaskutega pükse. Aeg-ajalt haarasid sahtlid ja käepidemed nendel taskuvoldist. Sarnane probleem tekkis jopetaskutega, mille klapid olid ette suunatud ja mis seetõttu näiteks ukselingiga haakusid kui uksest lähedalt mööduda. Kinnijäämise vähendamiseks peaks taskuklapp olema kinnitatud tasku eesmisele poolele, kuna inimene liigub enamasti edasisuunas. Tasku tagaküljel oleva klapi loogika on ilmselt, et klapp peaks olema tasku ülemisel küljel, mis diagonaalse tasku puhul on tagakülg (kõigil diagonaaltaskutel, mida näinud olen, on avaus ees kõrgemal).