27th January 2019, 4 min read

Science and Technology links (January 26th, 2019)

1. We are training many more doctors (PhDs) than we need, when looking at the number of new faculty positions. In science, this has been true since at least the 1980s. It is not uncommon for even so-so faculty positions to receive dozens of top-notch applicants with PhDs. Yet it is often believed that for a new PhD, anything short of a professorship is a failure. Logically, PhD students should prepare for a job in industry and I often try to prepare my own students in this way. Some students believe that hinting that they need to prepare for an industry job is an insult. Jeff Dean is probably one of the ten most famous computer scientists in the world. He works for Google and he has a PhD. He wrote on Twitter:
   

When I was finishing grad school, I was applying for both academic faculty positions and industrial research positions. Only got one academic interview (& offer), and not from a top- or even mid-tier place, so I went into industrial research. It’s turned out okay.

My own unpopular view is that governments put too much money toward funding new PhDs. We confuse too easily training new PhDs with doing science. We generate many, many PhDs that are too often poorly prepared for the actual jobs they may find.

1. Cape Town (South Africa) and Magadan (Russia) are 22 thousands kilometers apart. It would take two years to walk the distance. Though it is a long time, it also puts in perspective the fact that it often took hundreds of years for technological innovations to spread from one corner of the Earth to the other.
2. We have no serious evidence that artificial sweeteners are harmful.
3. The Guardian tells us that up to 1,500 private flights will bring world leaders to Davos to take urgent action on climate change. Al Gore, the author of the celebrated “Inconvenient Truth” documentary on climate change resides in a 10,000 square-foot home with eight bathrooms, he uses orders of magnitude more electricity than regular folks. He also charters private flights. Similarly, in my experience, climate-change researchers (including some close colleagues of mine) routinely fly to remote locations. The counterargument is usually that people buy carbon offsets. Roughly speaking, what these offsets do is, for example, pay for a poor village to receive a solar panel, thus replacing their inefficient CO2-emitting generator. That is what happens when these carbon offset programs are genuine and well managed. However, do these offets really work? That is, will the poor village with subsized electricity now use this new wealth to buy a new car? Who gets to measure the environmental effect of these carbon offsets, and what are their incentives? Anderson wrote an essay for Nature a few years ago on this topic:
   

Offsetting is worse than doing nothing. It is without scientific legitimacy, is dangerously misleading and almost certainly contributes to a net increase in the absolute rate of global emissions growth.

Corbera and Martin are similarly skeptical:

carbon-offsetting activities have (…) not been able to meet their stated goals (…) the carbon-offset market is designed to serve polluters

A major initiative to offset climate change is REDD: in short, rich countries pay poor countries to preserve their forests. The key idea, just like other carbon offsets, is that the rich country does not need to change its practices. In Why REDD will fail, DeShazo et al. explain why it may not work as you expect:

the eventual goal of REDD is that developed countries will pay developing countries to protect and enhance their forests in order to offset carbon emissions. This practice allows developed countries to claim that they are reducing emissions when no actual reduction has taken place (…) should a developing country adopt REDD (…) this does not equate to a reduction in deforestation.

Carbon offsets work in specific ways: they make some people feel better and allow virtue signalling. However, you should not believe that we could all live in mansions with eight bathrooms and fly private jets without increasing our carbon emissions, if only we paid for carbon offsets. You should not believe that researchers and world leaders can keep on organizing conferences at Davos without significant environmental impacts. These are extraordinary claims that require extraordinary evidence. They just happen to be convenient beliefs.

1. As we age, our bones tend to break more easily. We also accumulate senescent cells: cells that should be dead but somehow survive. Though it is not yet ready for actual therapies, we now have technology to remove senescent cells. Farr and Khosla find that removing senescent cells in old mice prevent age-related bone loss and frailty.
2. A bacteria that causes gum disease might cause Alzheimer’s.
3. Scandinavians with weird names were more likely to emigrate to the United States. People with weird names would be more individualistic. Both times my wife was pregnant, I insisted on us picking original first names. I would define myself as an individualist.