New report: Children exposed to pornography might get the impression that sex is pleasurable.

Is sex pleasurable? As I young teenager I had no idea, because the "sex education" I received from my school (and my nervous father) omitted that critical topic. I was given information that amounted to "plumbing," devoid of any social context. That's how it was back in the 60's for many of us. For personal historical reasons, then, I especially enjoyed this new report by Onion Network News: Study: Children Exposed To Pornography May Expect Sex To Be Enjoyable

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I once saw Lex Luther do it . . .

Can human beings cause earthquakes? Scientists are seriously debating this issue. Some are suggesting that the immense amount of water piled behind the Zipingpu Dam triggered a nearby fault that killed 80,000 people in China. The story is covered in the January 16, 2009 edition of Science (available online only to subscribers.). The reservoir began filling in 2004 and the 7.9 earthquake occurred in 2008. The article cites seismologists who claim that you don't need much mechanical disturbance to trigger it an earthquake.

Removing fluid or rock from the crust, as in oil production or coal mining, could do it. So might injecting fluid to store waste or sequester carbon dioxide, or adding the weight of 100 meters or so of water behind the dam.

Some scientists suggest other possible occurrences. For instance, they suggest that the water piled behind the Koyna Dam caused a 6.3 trembler that killed 200 people in India in 1967. I do realize that earthquakes can be lethal, so I shouldn't sound as though I'm making light of them. The reason for the title is a chapter of the original Christopher Reeve Superman Movie. In the movie, Villain Lex Luthor started an earthquake by aiming an atomic warhead cruise missile along the San Andreas fault. That part of the movie is something I wondered about for many years. Can humans set off earthquakes? Based on this article in Science, the notion is at least plausible.

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Bacteria that talk to each other

Bonnie Bassler, who teaches molecular biology at Princeton, explains that bacteria don't just grow and divide, grow and divide. They speak to each other and with other species of bacteria through their chemicals. Bassler studies how bacteria use chemical signals to act as coordinated social units. In this delightful TED talk, Bassler discusses how her research group has studied the manner in which bacteria talk to each other. They make chemical "words" to enable group activities (such as triggering the timing for effective virulence attacks), sensing each other through their "quorum-sensing molecules." They can also sense the difference between themselves and other bacteria. Note that each of us is 99% bacterial. Our human body consists of about one trillion of "our own" cells, but ten trillion bacteria. We have about 30,000 of "our own" genes, but we carry about 100 times more bacterial DNA than human DNA. Bacteria live as "mutualists" with us. They help us digest our food, make our vitamins, protects us from other pathogens and help us survive in numerous other ways. Rather than using antibiotics to kill bacteria (which inevitably selects for more virulent strains), Bassler suggests that a better understanding of the communications schemes used by bacteria is allowing scientists to develop potent new medicines. This is an upbeat and informative talk regarding a most ancient form of life.

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Flimsy eyewitness testimony

You often hear people claiming that the case is strong because there was an "eyewitness." It's becoming increasingly clear, however, that eyewitness testimony is often worse than useless. Modern DNA testing has exposed just how weak eyewitness testimony can be, as presented Radley Balko, in Reason:

Law and Human Behavior, false eyewitness testimony contributed to 77 percent of the 230 wrongful convictions exposed by DNA evidence over the last decade (the number of exonerations has grown since the study was conducted). These of course are only those cases for which DNA testing was available, which are usually murder and rape cases—crimes for which, generally speaking, there is also usually other evidence available. In crimes where investigators are more likely to rely only on eyewitnesses, robberies or muggings, for example, it’s likely that the problem is even more pronounced.

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