Tag: virus

Air Pollution


Tiles to reduce air pollution in a city, respiratory oases. I love it when architecture solves problems instead of creating them (ie suburbia):

The tiles are coated with titanium dioxide (TiO2), a pollution-fighting technology that is activated by ambient daylight. TiO2 is a photo-catalyst already known for its self-cleaning and germicidal qualities; it requires only small amounts of naturally occurring UV light and humidity to effectively reduce air pollutants into harmless amounts of carbon dioxide and water. When positioned near pollution sources, the tiles neutralize NOx and VOCs (volatile organic compounds) directly where they are generated. They transform previously inert urban surfaces into active surfaces, re-appropriate polluted spaces for safer pedestrian use, and invert problem spaces – dark, polluted, uninhabitable – to benevolent spaces that benefit communities.

2007-01-03: PigeonBlog

PigeonBlog enlists homing pigeons to participate in a grassroots scientific data gathering initiative designed to collect and distribute information about air quality conditions to the general public. Pigeons are equipped with custom-built miniature air pollution sensing devices enabled to send the collected localized information to an online server without delay. Pollution levels are visualized and plotted in real-time over Google’s mapping environment, thus allowing immediate access to the collected information to anyone with connection to the Internet.


2007-09-13: World’s most polluted places as a MyMap.
2014-06-29: US Air Quality Improvement. I like to highlight the occasional good news when it comes to the environment.

Air pollution has decreased even though population and the number of cars on the roads have increased. The shift is the result of regulations, technology improvements and economic change. New York City has seen a 32% decrease in nitrogen dioxide between the 2005-2007 and 2009-2011 periods.


2014-11-26: Pollution can be cleaned up quickly. This should make China’s pledge to improve air quality / reduce greenhouse gases quite feasible.

In 2002, South Korea was ranked 120th for air quality, and 43rd in 2014

2015-09-23: VW 1M tons of pollution. It is time to get tough, and destroy VW.

Volkswagen’s intentional fraud resulted in an extra 1M metric tons of air pollution being spewed into the skies over America; if they’d extended the con to Europe (where there are far more diesels), it would have been orders of magnitude worse.

2017-06-01: Electric Vehicles Are Cleaning Up

In regions that lean heavily on coal-fired power plants, plug-in cars can end up polluting more heavily at the smokestack than gasoline cars at their tailpipes. But as grids get greener, that’s becoming less true nationwide.

2017-06-17: Schlieren Imaging. This is what the world would look like if you could see invisible air currents, temperature gradients, and differences in pressure or composition of the air

2018-01-22: Far UVC disinfection. There’s part of the uv spectrum that kills viruses & bacteria, but does not damage skin.

2018-08-23: Too much CO2 affects sleep

If CO2 can affect sleep quality, that would explain how it could produce a whole-day effect. Strøm-Tejsen tests this on 16 subjects and finds that “objectively measured sleep quality and the perceived freshness of bedroom air improved significantly when the CO2 level was lower, as did next-day reported sleepiness and ability to concentrate and the subjects’ performance of a test of logical thinking.” Good things about this study: subjects were blinded to condition, the paper contains a pilot experiment and a main experiment which mostly replicate each other’s results. Bad things about this study: the experiments were about n = 15 each, the researchers didn’t correct for multiple comparisons, and they admit to manipulating the statistics surrounding their logical reasoning tests to get better results.

2020-08-23: Health benefits of clean air

Ditching fossil fuels would pay for itself through clean air alone. Over the next 50 years, keeping to the 2°C pathway would prevent 4.5m premature deaths, 3.5m hospitalizations and emergency room visits, and 300m lost workdays in the US.

2021-09-28: UV is very effective.

air filtration and UV disinfection can greatly reduce SARS-COV-II in hospital wards. The authors installed portable air filters with UV disinfection on 2 COVID hospital wards in the UK. The air was tested for viruses, bacteria and fungi before the filters were turned on, during the time the filters were on and then again after the filters were turned off. Airborne SARS-CoV-2 was detected in the ward on all 5 days before activation of air/UV filtration, but on 0 of the 5 days when the air/UV filter was operational; SARS-CoV-2 was again detected on 4 out of 5 days when the filter was off.


2022-03-28: 98% reduction in 5 minutes

“Far-UVC rapidly reduces the amount of active microbes in the indoor air to almost 0, making indoor air essentially as safe as outdoor air” The lamps inactivated more than 98% of the airborne microbes in 5 minutes. The low level of viable microbes was maintained over time, even though microbes continued to be sprayed into the room. The efficacy of different approaches to reducing indoor virus levels is usually measured in terms of equivalent air changes per hour. In this study, far-UVC lamps produced the equivalent of 184 equivalent air exchanges per hour. This surpasses any other approach to disinfecting occupied indoor spaces, where 5-20 equivalent air changes per hour is the best that can be achieved practically.

2022-08-19: Startups are entering this space to bring the cost down.

Beam ($5000) is an LED-based, upper room disinfection device that uses 265-nanometer ultraviolet light to create a disinfection zone located above people in a room. Vive ($3000), meanwhile, uses a wavelength known as far-UVC at 222-nanometers to inactivate harmful microorganisms in the air and on surfaces, even while people are present. While the Beam works in large open spaces, like classrooms and office lobbies, the Vive can be installed in smaller spaces, such as conference rooms and bathrooms. “What we have come to realize is that there is not one-size, fits-all for infection protection. What Arc competes with is some form of chemical intervention. For Beam and Vive, it’s HVAC upgrades.”

2022-10-28: Without massive improvements to LEDs, far UVC is not practical due to cost. Unclear what the deal with these startups is but I suspect they don’t output enough power to be effective.

$2000 is a ballpark retail price for a lamp installed by specialists, and the lamps have an expected lifetime of 15 months if they run continuously. There’s hope that far-UV lamps based on LEDs will eventually provide cheaper and longer-lived alternatives to the gas lamps currently being used, but prototype LED far-UV lamps are currently restricted to impractically low levels of power.

2023-09-15: Giant progress in China

China’s pollution levels in 2021 had fallen 42% from 2013. The improvement means the average Chinese citizen’s lifespan is now 2.2 years longer. Chinese cities used to dominate global rankings of the world’s worst air quality; while some are still on those lists, in many cases they have been overtaken by cities in South Asia and the Middle East. In 2021, Beijing recorded its best monthly air quality since records began in 2013. There is still work to do as China remains the world’s 13th most polluted country. And Beijing’s particulate pollution – the tiny but highly dangerous pollutants that can evade the human body’s usual defenses – is still 40% higher than in the most polluted county in the United States.

2024-05-08: What’s needed to make far UVC viable

Light in the 200-235 nm range, or far-UVC, is one of the most promising tools for dramatically reducing airborne transmission from day one of almost any pandemic caused by airborne pathogens. If adopted widely, it could also have a dramatic impact on seasonal flu, colds, and endemic COVID-19.

Unfortunately, progress on development and adoption has been much slower than one would have hoped. One bottleneck is the high cost and low efficiency of the only commercially available source at this wavelength range, 222 nm krypton chloride excimer lamps. For example, by our calculations, equipping a classroom with far-UVC would cost >$10k/classroom/year in lamps alone.
While directly supporting solid-state far-UVC R&D to accelerate availability is important, growing the far-UVC market in general and enabling greater private investment is even more critical.

Obesity

Riding on the metro in DC, I was informed that the 69M obese in the US are hype. I’m glad the food industry is looking out for me and even providing me with helpful cartoons.
2007-03-31: The obesity gas connection

US citizens are burning 3.7B liters of gas a year more than they did in 1960, because they are much heavier. That’s about $2.2B worth of fuel, and a lot of greenhouse gas emissions.

2007-04-27: Congress promotes obesity through agricultural subsidies. Ever heard of HFCS?
2007-09-11: plus the reduction in burger and fries consumption would cause less brazilian forest to be burned, further reducing emissions.

$1 in real gasoline prices would reduce obesity in the US by 15% after 5 years.

2007-09-18: No comment necessary.

Many 5-passenger vehicles are rated 385 kg, maxing out if their 5 occupants weigh more than 77 kg each. 6 90 kg people would overload the 7-passenger Dodge Grand Caravan minivan.

2008-03-29: More fatties are found, unsurprisingly.

More than 50% of American adults considered to have normal body weight have high body fat percentages — greater than 20% for men and 30% for women — as well as heart and metabolic disturbances. The finding conflicts with the widely held belief that maintaining a normal weight automatically guards against disorders such as high levels of circulating blood fats and a tendency to develop metabolic syndrome, which often leads to type 2 diabetes.

2008-12-22: The war against fat people has begun.
2010-06-08: Fighting obesity with that other staple, security. brilliant!

27% of all Americans ages 17 to 24 are too overweight to join the military. Now, the group of retired military officers that prepared the report is asking Congress to pass a nutrition bill that would make school lunches healthier.

2011-03-25: Obesity deaths

Since 2001, premature death from obesity has exceeded death from malnutrition.

2015-07-27: a large part of the decline is due to people drinking fewer sodas.

Calories consumed daily by the typical American adult, which peaked around 2003, are in the midst of their first sustained decline since federal statistics began to track the subject, more than 40 years ago.

2015-08-11: There are few public health interventions as beneficial as destroying the soft drinks industry.

Coca-Cola, the world’s largest producer of sugary beverages, is backing a new “science-based” solution to the obesity crisis: To maintain a healthy weight, get more exercise and worry less about cutting calories.

The beverage giant has teamed up with influential scientists who are advancing this message in medical journals, at conferences and through social media. To help the scientists get the word out, Coke has provided financial and logistical support to a new nonprofit organization called the Global Energy Balance Network, which promotes the argument that weight-conscious Americans are overly fixated on how much they eat and drink while not paying enough attention to exercise.

2016-03-23: soda taxes are very odd:

Why not just target the output, rather than some random subset of inputs? We could tax obesity if we wanted to. Or if we want to seem less punitive, we could award tax credits to obese people who lose weight. A tax directly pegged to reduced obesity would certainly be a much more efficient way to achieve the stated policy goal of reducing obesity. We are unwilling to humiliate the obese by taxing them directly, and so our chosen policies do less to help…the obese.

2016-12-31: Viral components of obesity?

During the experiment, both groups of chickens consumed the same amount of food. By the end of the experiment, only the chickens infected with the SMAM-1 virus had become fat. However, even though the infected chickens were fatter, they had lower cholesterol and triglyceride levels in their blood than the uninfected birds. “It was quite paradoxical,because if you have a fatter chicken, you would expect them to have greater cholesterol and circulating triglycerides, but instead those levels went in the wrong direction.” Though Dhurandhar and Atkinson have conducted several strong studies showing the contribution of Ad-36 to fatness, skepticism remains. “I remember giving a talk at a conference where I presented 15 different studies in which Ad-36 either caused or was correlated to fatness. At the end of it, a good friend said to me, ‘I just don’t believe it.’ He didn’t give a reason; he just didn’t believe it. People are really stuck on eating and exercise as the only contributors to fatness. But there is more to it.”

2018-08-16: Sugar is everywhere

Yes, we ate more in 1976, but differently. Today, we buy 50% as much fresh milk per person, but 5x more yoghurt, 3x more ice cream and – wait for it – 39x as many dairy desserts. We buy 50% as many eggs as in 1976, but a 33% more breakfast cereals and 2x the cereal snacks; 50% the total potatoes, but 3x the crisps. While our direct purchases of sugar have sharply declined, the sugar we consume in drinks and confectionery is likely to have rocketed (there are purchase numbers only from 1992, at which point they were rising rapidly. Perhaps, as we consumed just 9kcal a day in the form of drinks in 1976, no one thought the numbers were worth collecting.) In other words, the opportunities to load our food with sugar have boomed. As some experts have long proposed, this seems to be the issue.

2022-01-29: The energy balance theory is bogus

“People get fat because they take in more calories than they expend” is wrong. “Consider using the identical logic to describe, say, why people get wealthy. Economists would be embarrassed by a money-balance theory of wealth: People get rich because they take in more money than they spend. Clearly wealthy people did. We know that because they’re wealthy. The increase in wealth is the positive money balance. But this says nothing about how or why they accumulate such wealth. In obesity research, this tautological logic — saying the same thing in two different ways but offering no explanation for either — was allowed to become the central dogmatic truth.“ Then what does cause obesity? “People don’t get fat because they eat too much, consuming more calories than they expend, but because the carbohydrates in their diets — both the quantity of carbohydrates and their quality — establish a hormonal milieu that fosters the accumulation of excess fat.“

2022-08-14: Wegovy uses a hormone to regulate hunger. It’s wildly effective.

Once it becomes obese, the human body tends to push itself to rebound to its previous highest weight. Scientists don’t fully understand why, or how to stop it. Many speculate that our brains have not adjusted to living in a time of plenty. “There’s been a selection bias towards those people who could better protect body weight during times of famine. But now we don’t have a shortage of food.” When a patient stops taking Wegovy, their appetite returns within weeks and they pack on weight. Patients who came off the drug regained 7% of their body weight. “We used to think that behavior causes the weight state, but now we think the weight state actually causes the behavior”.

Fatality risk

we are experiencing “a disease that spreads like the common cold but kills 4% of its victims”. As far as I can tell, SARS is here to stay, and it will continue to spread. Will we be able to develop a vaccine or treatment before every person on earth experiences the disease?

will we have to mostly abolish international travel to stop an important vector of the disease? will globalization be one of goods and services only? will we shift more of our existence into cyberspace to reduce contagion? a 4% risk has to be put into perspective.

0.0005 %
risk of death on a dive
0.004 %
risk of death from mountain hiking
0.05 %
risk of death from motor vehicle accident
100 %
risk of eventual death

a master list of infectious diseases is available too.

Bangkok Day 3

After a nice breakfast at the incredible Atlanta, I head to town to work on my emails. At 14.00, I decide to go to a spa to make use of the 555 baht special deal where you can have massage, sauna, body scrub, manicure, haircut, for 20 bucks.

At 14.10, I call Siemens Thailand. They invite me over for an interview (so no spa today). I have a nice chat with them, resulting in a job offer around 16.00. Afterwards, I finish Bill Gates “Business @ the speed of thought:”. I then head back to the Atlanta, chill out until 20.00. On the street, I then get bitten by a stray dog. 22.00: Sun arrives at Oliver’s apartment. 24.00:Ii am in the hospital to get vaccination against rabies (which that stupid dog surely had) 1.00: I eat noodles with chicken on the street. 1.30: We are shaking it at Bangkok bar.
2022-07-27: I may have dodged a huge bullet on that day. Rabies is scary.