Tatyana Deryugina (Twitter: @TDeryugina)

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Posted 21 Jul 10 by Tatyana in Science

I just read a book about polio in the United States (don’t ask why). It has some amusing anecdotes…

When researchers were trying to study how polio is spread in the early 20th century, they infected monkeys through the mouth, nose, or other means to see what the disease passageways were. Monkeys only became infected through the nose, which was bad news because it seemed as though the virus didn’t need to pass through the blood to infect people, as most viruses do. Coming up with a vaccine was thus made that much more difficult.

Unfortunately, the researchers chose a monkey in whose stomach the virus couldn’t multiply. Had they chosen another species, they would have seen that the virus is perfectly capable of being spread through the mouth.

In another polio-related blunder, researchers were trying to produce a lot of the virus in hopes of using it for a vaccine. The way virus cultivation was done back then was through growing it in animal tissues. The researchers discovered that the virus only grew in monkey nerve cells, but not any other tissues. This meant that vaccine production would be very very very expensive and impossible to do quickly. They published their results in a scientific journal and the study was so well-documented that no one doubted its accuracy and discouraging implication.

Unfortunately, the researchers used a particular strain that only multiplied in nerve cells. Years later, when another set of researchers tried replicating a different strain, mostly for the hell of it, they found that it grew perfectly fine in kidney tissues (which can themselves be replicated, thus making virus-making very affordable).

Lesson of the day:  thoroughness counts.

Posted 09 Jul 10 by Tatyana in Science

While reading Scientific American, I came upon an article titled "Under Threat, Women Bond, Men Withdraw”. It describes the result of a controlled study comparing the responses of men and women to a stressful situation. Guess what situation they used. Tiger or mugger attacks? Nope. Confederates yelling at them? Nope. Taking a test? Nope. They put the hands of some volunteers in extremely cold water, then analyzed their brain activity. They found that brain activity in a certain region (responsible for empathy) was increased in women but suppressed in men.

The fact that the brain responds differently is interesting. But how do you go from that to concluding that this is evidence of women "engaging in nurturing and social networking, perhaps as a way to protect their offspring”? Sure, theory can allow you to make conclusions about the world based on abstract and artificial situations, but in this case the leap is astronomical. It might make a nice story roughly consistent with stereotypes of gender roles in hunter-gatherer societies, but that should be relevant for fiction books, not good science.

Posted 30 Apr 10 by Tatyana in General

Apparently, Larry Summers has a protege, a 3L who wrote an email asserting the possibility that intellectual performance differences between races might be partly genetic. As much as the writer tried to be politically correct (if there is a politically correct way to say something like this), the email got passed around (you can read about it here).

What is it about nature arguments that makes them so appealing? (By the way, when I say "nature”, I mean the unexplained gap AFTER you’ve accounted for observable characteristics of individuals).

Posted 01 Mar 10 by Tatyana in Science

A recent Scientific American article (you need to be a subscriber to read it though) demonstrated one of my favorite caveats about inferring whether something is good or bad for you by giving huge doses of it to lab rats (e.g. saccharin, which allegedly causes cancer, and tannins, which allegedly are good for you). As it turns out, hydrogen sulfide, nitrogen oxide, and carbon monoxide, which are all normally considered poisonous, play a vital role in regulating dilation in blood vessels, among other things.

The human body contains (and needs) trace amounts of gold and other things that in large quantities would kill us. What people are doing when they claim something is bad or good based on large amounts of a substance is assuming that the effect is linear (or at least monotonic). However, it seems that lots of things are bad in large amounts but good or necessary in small amounts. Something could also be bad (or neutral) in small amounts but good in larger doses, although it’s not as easy to think of an example. The key point is that it’s important to test comparable dosages.

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