
99.Sex Secrets of the Bi-Gender Chicken: These bizarre gynandromorphic birds are bizarre on the cellular level, too.

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This past year, two independent groups made notable advances in that direction. At the University of California, Berkeley, electrical engineer Ali Javey and his team attached a grid of nanowire transistors to a polyimide film placed atop a layer of rubber. The resulting electronic skin recognizes pokes and prods as changes in electric resistance. Meanwhile, at Stanford University, materials scientist Zhenan Bao and collaborators cut pyramid-shaped holes in an elastic polymer to produce variations in capacitance, the ability to hold an electric charge. In tests, the material could “feel” objects as light as a butterfly.
Beyond robots and artificial limbs, synthetic skin might be used someday in extremely responsive touch screens or in car devices that alert drivers if their hands slip off the wheel. “It would be nice if the machines we interact with could interact with human beings intelligently,” Bao says.

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Now the reason for this inconsistency is becoming clear. In October a team of scientists published the sequences of the genomes of 13 strains of Borrelia burgdorferi, the bacterium that causes Lyme disease. “Different strains have different capacity to cause disease,” explains infectious-diseases physician Benjamin Luft of the State University of New York at Stony Brook. “We now have a more complete picture of the pathogen and the genes that may be related to the disease.”,

Our immune system cannot always make antibodies —proteins that surround and deactivate pathogens— quickly enough to neutralize aggressive viruses. Vaccines prime the system to build antibodies before infection, but they can be expensive to develop, slow to produce, or elusive. In March chemists created a promising alternative: a synthetic antibody that can disable a pathogen in a living animal.
Ken Shea and colleagues at the University of California, Irvine, used melittin, the toxin in bee venom, as the antigen (the substance triggering an immune reaction). Melittin particles hold a positive charge, so Shea created a negatively charged polymer. He added melittin so the polymer particles formed with a molecular imprint of the toxin’s shape. The plastic nanoparticle attracted the toxin and fit it like a cast, neutralizing it.
Shea gave mice a lethal dose of melittin, then injected half the animals with his plastic antibodies. All the unprotected mice died, but almost 60 percent of the treated ones survived. The experiment shows how antibodies might be built quickly in the lab, “a decided advantage if some unknown horrible disease might appear,” Shea says.
Berger thinks Karabo and an adult female found nearby represent a new hominid species, Australopithecus sediba, that may have been the first to walk upright the way modern humans do. A. sediba had long, apelike arms; a braincase one-third the size of a modern human’s; and a modern-looking pelvis that suggests it was a better upright walker than previous australopithecines.
Others contend the two are not human ancestors at all because they appeared around 400,000 years after the first evidence of H. habilis, the earliest in the Homo line. “Sediba is too late to sit on the lineage,” says paleoanthropologist Tim White of the University of California, Berkeley. Berger counters that the only fossils that can be definitively classified as H. habilis showed up after A. sediba. “Australopithecus sediba is the best candidate for a transitional species,” he argues. “It’s more advanced than Homo habilis, which appears later. It probably means Homo habilis is not really an ancestor of anything.”
Earlier efforts to hunt down disease-causing genes—so-called genomewide association studies—frequently came up empty-handed because medical researchers had to take cost-saving shortcuts. Instead of trolling an individual’s entire genome, they limited their search to dna regions where variations are most often seen across large populations. “It was assumed that common variants might be responsible for common diseases, but many diseases turn out to have many different rare variants at their root,” says James Lupski, a medical geneticist at Baylor College of Medicine in Houston. “That’s why the power of whole-genome sequencing blows us away. It’s the only way we can get at these rare variants”...

The massive gush of oil that started on April 20 and ran for 86 days was a disaster, obviously, but it was also a grimly informative experiment. In its wake we are learning all kinds of lessons about deep-drilling technology, about the environment and ecology of the Gulf of Mexico, and about the future direction of our energy supply.
It may be hard to appreciate now, but 2010 started as a banner year for oil. The world’s energy giants were on the move, dispatching their sharpest petroleum engineers, sophisticated seismic probes, and huge rigs to some of the most forbidding places on the planet, from the Gulf of Mexico to Greenland. Corporate boardrooms gushed with confidence. “BP operates at the frontiers of the energy industry,” the company announced in its 2009 annual report. “We are exceptionally well placed to sustain our success in the deepwater Gulf of Mexico over the long term.”
The economic message from all of this exploration still holds true: The world is not running out of oil—it is running out of easy oil. By using the new technology, remote stashes of oil long dismissed as too difficult or expensive to plumb (in the 30- to 65-million-year-oldLower Tertiary crust below the Gulf, or in the even more ancient Cretaceous sedimentary rocks off the coasts of Ghana and Brazil) are within reach. Innovative prospecting techniques like three-dimensional sonar, which emits sound waves from multiple angles, help discovery crews see through opaque and shifting layers of geological salt to pinpoint oil hidden four miles or more beneath the Gulf of Mexico and off the Atlantic coasts of South America and Africa. Ultra-strong flexible pipes, remote flow-control valves, and vibration-resistant drill rigs can protect the prospecting equipment against corrosion, thermal shock, and crushing water pressure at the ocean floor.
The environmental message of the worst offshore oil spill on record (4.4 million barrels) is less clear and still unfolding...
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