Elledge’s group studied human cells in culture and mapped their response to ionizing radiation and ultraviolet light. Specifically, the group looked to see which proteins in the cell were chemically altered by the enzymes ATM and ATR, finding 900 sites on 700 proteins that changed in response to DNA damage. The discovery that so many proteins are involved in the process, Elledge said, was a big surprise.

Despite the abuse our DNA endures, our individual genomes usually stay basically intact because DNA has a remarkable capacity for repair. Our cells have built-in, highly efficient machinery that finds and fixes “genetic typos.”
…
Researchers have learned much about the complex genetic machinery that cells deploy to fix broken, cut, mutated, and misplaced genetic materials. Out of that evolving understanding has emerged a deeper awareness that DNA is truly dynamic and that responses to genetic damage are nearly as fundamental to life—and health—as is the genetic code itself.

Our mission is to improve education around the world by empowering teachers, students and parents with user-created, open source curricula, and it’s all free! We believe that access to knowledge and learning tools is a basic right of every child. Our goal is to make curricula and learning resources available to everyone.

Georgia Tech, which has branded the robot the “new face of computing,” is hoping that the class can be a new national model to teach students computing. To Microsoft Corp., which is investing $1 million to jump-start the program at Georgia Tech and Bryn Mawr, it’s investment in what could become its work force.

Outside groups have applauded the effort, too. “In fact, computing is a tool that can be used for virtually every application — from entertainment to medicine,” said Virginia Gold of the Association for Computing Machinery. “And the Scribbler helps show how pervasive computers are in everything.” The computing industry has a reason to be concerned about the future.

The number of new computer science majors has steadily declined since 2000, falling from close to 16,000 students to only 7,798 in fall 2006, according to the Computing Research Association. And the downward trend isn’t expected to reverse soon. The association says about 1 percent of incoming freshmen have indicated computer science as a probable major, a 70 percent drop from the rate in 2000.

And what do I now hear from PLOS? Do I hear the grinding of lawyerly knives? No. I hear the blissful silence of Open Access, a slowly-spreading trend in the journal world. PLOS makes it very clear on their web site that “everything we publish is freely available online throughout the world, for you to read, download, copy, distribute, and use (with attribution) any way you wish.” No muss, no fuss. If I want to blog about this paper right now, I can grab a relevant image right now from it.

Next morning, I woke up to a comment by the Managing Editor of PLoS ONE asking if my blog-post should be considered as a formal job application. My comment in response was a Yes.

Most students coming into a high school computer science course are expecting to be able to program mind blowing 3D games within a semester. When most find out that they won’t be able to come close to doing so within their single course of computer science class, most bid adieu to it and move on. Students learn that playing video games is a very small subset of computer science, and find this fact discouraging. This is where many students also lose a lot of interest in computer science. They don’t care about sorting through arrays or lists of data, or coming up with algorithms to solve problems. For this reason, a balance must be found between teaching computer science concepts, and applying the learned concepts in an engaging manner.

My kids and I actually had the first successful test flight of the sub-$1,000 UAV two weekends ago, but I haven’t had time to edit the video properly until now. The good news is that a) it didn’t crash, and b) it works. We tested stabilization, autonomous navigation (only using compass headings this time, although GPS is in the works), and the real-time video downlink. Everything worked well enough that we’re able to see what we have to improve, which is the definition of a successful test.
…
The main aim of this project is to both make the world’s cheapest full-featured UAV and the first one designed to be within the reach of high school and below kids, as a platform for an aerial robotics contest. Like the Lego FIRST league, but in the air.

the way they watched the process was to sequence the whole genome of each bacterial isolate. What they found were a total of 35 mutations, which developed sequentially as the treatment continued (and the levels of resistance rose). Here’s natural selection, operating in real time, under the strongest magnifying glass available. And it’s in the service of a potentially serious problem, since resistant bacteria are no joke. (Reading between the lines of the PNAS abstract, for example, it appears that the patient involved in this study may well not have survived).

The technology involved here is worth thinking about. Even now, this was a rather costly experiment as these things go, and it’s worth a paper in a good journal. But a few years ago, needless to say, it would have been a borderline-insane idea, and a few years before that it would have been flatly impossible. A few years from now it’ll be routine, and a few years after that it probably won’t be done at all, having been superseded by something more elegant that no one’s come up with yet. But for now, we’re entering the age where wildly sequence-intensive experiments, many of which no one even bothered to think about before, will start to run.

The journey to Dr. Moll’s terrifying discovery began in early 2005, when he noticed something peculiar. The staff at his hospital had become accustomed to the marvellous “Lazarus effect” of anti-retroviral treatment for AIDS: seeing desperately sick people quickly start gaining weight and return home or go back to work. But now, in his ward, he had two men in their 30s on ARVs whose HIV infections were suppressed to undetectable levels. Yet their TB, which would normally have cleared up in a matter of weeks, kept getting worse.

He suspected multidrug-resistant TB, or MDR, believed at the time to be as bad as the disease could get. So he collected sputum from 45 patients and sent it off to a lab in Durban for cell culturing. (The only way to tell if a TB strain is drug-resistant is to grow cultures from a patient sample, zap it with the different drugs and see which, if any, fail to kill it.) The process takes six to eight weeks. “In that time, we more or less forgot about it,” Dr. Moll said. One of his two young men died.

But the phone call from the lab, when it eventually came, slammed the issue to the top of their agenda: Of the 45 samples, 10 were indeed drug-resistant. But they weren’t resistant to just one or two of the drugs used against TB. They were resistant to all six medications available for use in Tugela Ferry. In other words, there was nothing to cure that TB at all.

Using a retrovirus that targets dividing, or reproducing, cells, the team tracked new neurons in the hippocampus (a midbrain structure involved with learning and memory) from their births to their deaths. The scientists could determine the behavior of cells by measuring their electrophysiological activity during different phases. “In young animals, cells are very active, very plastic, and they can change their properties readily,” he says. “This whole process [also] happens in the environment of adult circuitry.”

The team found that there is a two-week window, or critical period, about a month after these new cells hatch during which they act like the neurons of a newborn baby. The researchers cued the new cells with a pattern of electrical activation that mimics the sequence that takes place in the brain of a mouse as it learns about a special spot (such as a corner in its cage where it may receive food or a shock). During this time, the cell synapses (connections that allow neurons to communicate with each other) that are artificially stimulated become stronger.

The Curious Cat is a blog collecting news on science and engineering — but if the old saw is true, than that poor cat’s days are numbered. Or maybe the cat belongs to Schrodinger, and so exists in a quantum state between life and death, and as such artfully avoids the fate that excessive curiosity would usually visit upon a feline.

Most likely, the computer you’re using wastes 30-40% of the electrical power it consumes because it is using an inefficient power supply. It’s difficult to believe that something as basic as a power supply could be responsible for that amount of waste, but it’s true.
…
The opportunity for savings is immense — we estimate that if deployed in 100 million PCs running for an average of eight hours per day, this new standard would save 40 billion kilowatt-hours over three years, or more than $5 billion at California’s energy rates.
…
The net result of these changes is a dramatic improvement in efficiency (including the power supply and the regulators) to about 85%, at virtually no cost. In other words, you won’t have to pay more for a higher-efficiency PC, because the power supply is actually getting simpler, not more complicated. By spending another $20 or so extra, it is possible to use higher-quality components and achieve efficiencies well over 90%.

A team of American and Irish researchers have discovered that some female sharks can reproduce without having sex, the first time that scientists have found the unusual capacity in such an ancient vertebrate species. The[y] report that sharks can reproduce asexually through the process known as parthenogenesis
…
Though the three females had been caught before they reached sexual maturity and held in captivity for more than three years, researchers initially thought one had stored sperm from a male shark before fertilizing an egg. But the team — which included scientists at Nova Southeastern University in Florida, Queen’s University Belfast and the zoo — determined that the baby shark’s genetic makeup perfectly matched one of the females in the tank, with no sign of a male parent.

Mahmood Shivji — Nova Southeastern’s Guy Harvey Research Institute director and one of the paper’s authors — said that he and his colleagues determined that a byproduct formed when sharks produce eggs, known as a sister polar body, had fused with an unfertilized egg to produce the baby shark, whose DNA had only half as much genetic variability as the mother.

Carnegie Mellon University’s Randy Pausch…argues, many computer science departments are a quarter century behind on adapting their instructional methods for the purpose of attracting and retaining students, continuing to teach the gateway course to the field — introductory programming — just as they did 25 years ago.
…
About 10 percent of the nation’s colleges now use Alice, an open-source, graphical software program available free online that allows users to learn the very basics of programming — concepts like iteration, if statements and methods — while making 3-D animations. Alice’s growth within college computer science departments has been impressive: Most colleges only began incorporating Alice in their introductory CS0 or CS1 courses within the past 18 months, since the release of an accompanying textbook.

But the software, currently readable to users in plain old English (a major drawback for many faculty who of course teach programming in standard computer languages like Java and C++), is potentially poised to penetrate far more colleges in 2008, when Alice 3.0 comes out in Java — featuring, this time around, sophisticated graphics, made available free by Electronic Arts Inc., from “The Sims,” the best-selling PC video game of all time. (And significantly, Pausch adds, one of the few games more popular with girls than boys. Computer science, he notes drily, has the unfortunate distinction of being the only discipline in the sciences to actually face declining female enrollments percentage-wise in the last 25 years).

These remote-controlled submarines fit into the palm of your hand and have dual propeller propulsion systems that allow omnidirectional movement underwater in a bathtub, swimming pool, or in shallow ponds. The submarines dive and surface like an actual naval submarine, and the three high-powered motors ensure rapid movement forward, backward, left, right, and while performing 360 progressive rolls. The submarines have dual LED headlights and each unit operates on a unique radio frequency, allowing underwater races with multiple submarines. Includes rechargeable batteries that run for three minutes after a three minute charge.