29th December 2018, 2 min read

Science and Technology links (December 29th, 2018)

1. Low-dose radiation from A-bombs elongated lifespan and reduced cancer mortality relative to un-irradiated individuals (Sutou, 2018):
   

The US National Academy of Sciences (NAS) presented the linear no-threshold hypothesis (LNT) in 1956, which indicates that the lowest doses of ionizing radiation are hazardous in proportion to the dose. This spurious hypothesis was not based on solid data. (…) A-bomb survivors (…) showed longer than average lifespans. Average solid cancer death ratios of(…) A-bomb survivors (…) were lower than the average for Japanese people (…), essentially invalidating the LNT model. Nevertheless, LNT has served as the basis of radiation regulation policy. If it were not for LNT, tremendous human, social, and economic losses would not have occurred in the aftermath of the Fukushima Daiichi nuclear plant accident. For many reasons, LNT must be revised or abolished, with changes based not on policy but on science.

This is important work. I am surprised at how few people know about hormesis. Many people assume that if you avoid stress, toxins and challenges, you will maximize your health and longevity. That is just flat out wrong.

1. In climate talks, we use year 1850 as a reference: the implicit goal is to maintain Earth’s global temperature close to the global temperature that existed in year 1850 (say within 1.5 degrees). To my knowledge, nothing makes year 1850 special. In fact, in the absence of both ancient and recent carbon emissions from agriculture and industrialization, current global average temperatures would likely have been about 1.3 degrees lower than they were around 1850 (Vavrus et al., Nature 2018). We were headed down toward another glaciation and, instead, due to human beings, we are headed toward warmer and warmer temperatures. Left unchecked, neither direction is desirable. As argued by Deutsch in the Beginning of Infinity, we have no choice but to accept that there is no such thing as “sustainability” (which assumes an ideal steady state) and that we must learn to engineer our climate.
2. Human beings do not originate from a single region in Africa: the story of our origin is complicated, involving a mix of different populations and cultures.
3. McGuff and Litte (2009) write:

there is no additional physiological advantage afforded to one’s body, including endurance or cardio benefits, by training that lasts more than six to nine minutes a week.

1. The videogame Fortnite lead to 3 billion dollars in profit for its creators. It has 200 million players.
2. In older mammals, the skin loses fat. Zhang et al. restored the ability of skin in older mice to store fat, thus making the skin more resistant to some infections.
3. Students who make friends and study with them tend to do better. This is painfully obvious to anyone who has given serious thought to how schooling works.