Daniel Lemire's blog

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Science and Technology links (April 21st, 2017)

Can we trust software? Lance Fortnow, a famous computer scientist, answers

Sometimes I feel we put to much pressure on the machines. When we deal with humans, for example when we hire people, we have to trust them, assume they are fair, play by the rules without at all understanding their internal thinking mechanisms. And we’re a long way from figuring out cause and effect in people.

Luc Charlebois is a real-life Deus Ex character. He lost his leg ten years ago in a bike accident. The leg was just pulled off. He went to Australia where they remade his leg from scratch. He has an artificial leg that is directly connected to his skeleton. He can now walk and says that he when he does so, it “feels” like a true leg. That last part is critically important: we are a long way from wood pegs. But he had to spent a quarter of a million dollars to get it done. That’s not crazily expensive, but clearly out of reach to too many people. Given that this is now possible how long before we all ask for such high-quality artificial limbs?

Apple (the company) is allowed to test self-driving cars in California. “Siri, bring me back home.”

Daniel Lakens, an academic with a brilliant publication record, writes that blog posts are of higher scientific quality than journal articles. What he actually demonstrates is that it is quite easy to outdo scientific articles with something as silly as a blog post.

Using genetic engineering, we could one day selectively kill just one type of bacteria. This would turn modern-day antibiotics into blunt tools.

Want a growing industry? What about plastic surgery?

Somewhat mysteriously, obesity is a risk factor for bone health. Basically, beyond a certain point, the fatter you are, the more likely it is that your bones will break. That’s true even though heavier individuals tend to have higher bone mineral density. What is interesting is that we do not know why that is.

Currently, anesthesia is full of negative side-effects. Scientists are finding out that we could design better drugs that are free of these inconvenient side-effects.

The lens in our eyes tend to darken with age leading to a loss of vision, called cataracts. It is considered more or less unavoidable meaning that if you are old enough, you will have cataracts. We can simply replace the natural lens of your eyes, so it is not a crippling condition. There are several risk factors such as diabetes, age, sunlight… but wearing sunglasses, avoiding donuts, and staying inside won’t prevent cataracts. So what causes it? According to Beebe et al. it is the exposure of the lens to oxygen. Under normal conditions, in healthy young individuals, there is very little oxygen around the lens. But a liquefaction of the vitreous body of the eye or hyperbaric oxygen therapy can cause the lens to become exposed to oxygen, leading up to cataracts. Basically, your lens don’t interact well with oxygen. There is some evidence that if we can stop the exposure to oxygen, the lens could recover. Interestingly, we know how to repair the vitreous body with synthetic gels. So it is conceivable that we could one day develop preventive therapies against cataracts. At a high level, it might be as simple as keeping the vitreous body of the eye intact. The problem right now is that no doctor can tell you how much oxygen your lens are exposed to. So it is a difficult problem to study and catalog.

Netflix is reaching 100 million subscribers. This is far, far ahead of any cable TV company. In fact, cable TV companies are losing subscribers. Television is dying.

Following speculative claims that bees were being wiped out by the newest pesticides, neonicotinoids, the European Union banned these pesticides. Contrary to pesticides that you spray on the field, neonicotinoids are applied specifically on the seeds. These pesticides remain in wide use in Australia and North America, where both wild and honey bees are doing fine. Here is Matt Ridley on the consequences of the European ban in the Times:

In Britain, (…) farmers have more than quadrupled the number of insecticide applications on oil-seed rape (from 0.7 to 3.4 per growing season), but pest pressure has increased. Meanwhile, recent studies have demonstrated that declines among wild bees are driven mostly by land use changes and have not increased since neonics were introduced in the 1990s (…) This makes sense because neonics are mostly used as seed dressings, absorbed into the plant from germination, rather than sprayed on a growing crop. This makes them more lethal to pests such as flea beetles that eat the crop but less dangerous to innocent bystanders, including bees that collect pollen and encounter lower doses.

We ought to be critical of new technologies, but there is a difference between rejecting progress and being cautious. Some people do not want technological progress and they have much clout. In diseases like Alzheimer’s, the environment of the brain deteriorates to the point that brain cells die. This lead to brain shrinkage and to cognitive decline. We are having a really like time fixing the environment of the brain. However, some clever scientists found out that we could stop the cells from dying. The brain might still be full of bad proteins, but the brain cells can still be coerced into surviving. In early work, the researchers achieved this effect but using a drug that would be toxic to human beings. However, Halliday et al. have now shown that we can get the same good effect with safe drugs that are already used in human beings. Speculatively, this means that if we can find in time that the environment of your brain is getting toxic for some cells, we could give you one of these drugs to prevent your cells from dying. This would not qualify as a cure for, say, Alzheimer’s, but it could turn it from a death sentence to something we can manage with medication and monitoring.

For a time, it looked like the blood (actually the plasma) of your people could rejuvenate older people. This lead to a good deal of unwarranted mockery. There is still much ongoing work in this direction, but I expect that it will end up being a dead end because, as suggested by work from the Conboy laboratory in Berkeley, it seems that we have “aging factors” in our blood… and not so much “youth factors”. Specifically, as we age, we might get too much of some factors in our blood. Thus, we could age younger people with the blood of older folks, but the other way around is unlikely to work. What we might need to do is to identify and normalize the aging signals in our blood.

The classic game Starcraft is now available for free, for both PCs and Macs.

We have this model of reality where we are this one person throughout time. So I remember the teenager I once was. I think of him as “me”. This may actually only be true in a very teneous manner. Psychologists have found out that there is very little correlation (none at all) between your personality as a kid and your personality as an elderly person. On the short term, you remain who you are, but your personality progressively changes and there does not seem to be any solid long-term anchor. The teenager I was? In a very real sense, he is dead. I no longer think like he did. Not in a meaningful way. It also means that even if I remain healthy for a very long time, who I am today will die over time and be replaced by someone else. Thus you cannot endure as an individual. I view this as a good thing.

Apple co-founder, Steve Wozniak, predicts that by 2075, we will have a colony on Mars.

Naked mole rates are long-lived tiny mammals. We still do not quite understand why they live so long. Interestingly, they can survive without any oxygen at all:

When the oxygen was completely removed and replaced with nitrogen, the mice died after 45 seconds. The naked mole rats passed out. But even after 18 minutes of no oxygen, they recovered when they were put back in normal air.

Why should you care about naked mole rats? Well. They are mammals not very different from us. They mostly have the same genes we do, plus/minus a few. If we can better understand how the cells of naked mole rates, we could use technology to mimick them. So, eventually, our cells could be taught to survive with very little oxygen. This would make us far more robust.