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POPSZebra's Stripes, Butterfly's Wings: How Do Biological Patterns Emerge? Previous work identified a specific signal necessary for getting these fly egg cells to move; the problem is that this signal is “graded.” Like drops of ink spreading out on wet paper, this signal travels in between surrounding cells, gradually fading away as it moves outwards. But clear lines are required for pattern formation — there is no grey area between a zebra’s black and white stripes, between heart and liver cells and, in this case, between migrating cells and those that stay put. How are graded signals converted to a clear move or stay signal? By examining flies containing mutations in different genes, the researchers discovered that one gene in particular, called apontic, is important for converting a graded signal.
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POPSMy stroke of Insight "How many brain scientists have been able to study the brain from the inside out? I've gotten as much out of this experience of losing my left mind as I have in my entire academic career." Jill Bolte Taylor (TED talk video at source)
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POPSGetting coffee at A.placebetween.us This is brilliant. I can't tell you how many times I've bounced between google maps, citysearch, and menupages trying find something convenient to both me and the person I was meeting.
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POPSStaying alive: the women who are immune to Aids This is a long piece, and it's difficult in places. But it's worth it. More from the piece. I lay down to test the mattress: it was lumpy and totally unyielding, not the sort of place one would want to spend much time, which seemed a little odd, given the purpose of this room. Agnes Munyiva saw my wince, laughed and patted the bed. 'You need it to be hard, because otherwise you could get hurt when the men are pushing on you,' she explained. The mattress, stuffed with lumpy cotton and resting on a plain metal frame, fills most of her room, just one metre by two. The walls are made of mud, the roof of scraps of tin. The air has a tang from the raw sewage and rotting food scraps in the alley outside, and Agnes tries to keep the clouds of flies at bay with a crisp white muslin curtain in the doorway. Remnants of linoleum, pieced together like a quilt, cover most of the dirt floor. She has a kerosene burner for making tea and a gas lantern.
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POPSThe Relative Nature of Space and Time Okay, I'm sure you know what the two principles are, but just in case, let's go over them. Light, it has been determined, always travels at a constant speed, regardless of its source or the frame of reference. The other is the principle of relativity, which basically states that motion is relative. The combination of these two principles show that time is also relative. And as previously discussed, you can't separate time from space. So if time is relative, space must be also. How is it that time is relative?
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POPSIsrael's NAZI Kingmaker: Russian, Israeli, French, Canadian, Angolan.
He travels on an Angolan diplomatic passport to avoid arrest. His Jerusalem soccer team has a notoriously racist, anti-Arab fan base. Chant of "Death to Arabs" are regular. He has said, "Any politician that I will support will be the prime minister." Yet a Knesset committee has openly took issue with his actions during the war, accusing him of acting entirely for political reasons. To his supporters, he is simply the natural result of an Israeli establishment that is so wrapped up in corruption and cronyism that it is unable to care for its citizens. One important opponent said, "There is a sense among some people," he said, "that democracy just didn't work for us, and we should be like the rest of the Middle East -- that we tried democracy and failed. He's an oligarch. Don't forget that a lot of his supporters are Russians. They're not familiar with democracy." Handling of Moscow News is widely viewed as hostile to free speech and raised questions about his ties to Russia.
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POPSCan information get back out of black holes? With this assumption in hand, the team recalculated what the centre of a black hole might look like. To simplify their equations, they used only two dimensions instead of the three dimensions of space and one of time that exist in our Universe. In a two-dimensional system, they found that the singularity vanished and was replaced by a bizarre region where quantum fluctuations ran wild. Space-time in that part of the hole would become so unpredictable that all conventional ideas of cause and effect would break down. "Classical intuition fails in that region, but quantum mechanics is definitely happy," says Ashtekar, who will report the results in the 20 May issue of Physical Review Letters 1. If black holes behave in the way Ashtekar predicts, information will never be lost and quantum mechanics will continue to function, even in the extreme environment beyond the event horizon.
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