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Biotech

Submission + - Evidence found for Earliest Modern Humans

Hugh Pickens writes: "Researchers at Arizona State University report that they have pushed back the date for the earliest modern humans to 164,000 years ago, far earlier than previously documented. Paleoanthropologists now say that genetic and fossil evidence suggests that modern human species — Homo sapiens — evolved in Africa between 100,000 and 200,000 years ago and in seeking the "perfect site" to explore for remains of the earliest populations, researchers analyzed ocean currents, climate data, geological formations and other data to pin down a location. "The world was in a glacial stage 125,000 to 195,000 years ago, and much of Africa was dry to mostly desert; in many areas food would have been difficult to acquire. The paleoenvironmental data indicate there are only five or six places in all of Africa where humans could have survived these harsh conditions," said Curtis Marean, a professor in ASU's School of Human Evolution and Social Change. Photos from the cave at Pinnacle Point in South Africa show where the team found ochre, bladelets and evidence of shellfish — findings that reveal the earliest dated evidence of modern humans."
The Internet

Submission + - Infrequent Anonymous Cowards Reliable on Wikipedia

Hugh Pickens writes: "Researchers at Dartmouth University have recently discovered that infrequent anonymous contributors, so called "Good Samaritans," are as reliable as registered users who update constantly and have a reputation to maintain.

By subdividing their analysis by registered versus anonymous contributors, the researchers found that among those who contribute often, registered users are more reliable. And they discovered that among those who contribute only a little, the anonymous users are more reliable. The researchers were most surprised to find that the reliability of Good Samaritans' contributions were at least as high as that of the more reputable registered users' contributions. "This finding was both novel and unexpected," says Denise Anthony, associate professor of sociology. "In traditional laboratory studies of collective goods, we don't include Good Samaritans, those people who just happen to pass by and contribute, because those carefully designed studies don't allow for outside actors. It took a real-life situation for us to recognize and appreciate the contributions of Good Samaritans to web content."
A graph from page 31 of the group's original paper (pdf file) shows that the quality of contributions of anonymous users goes down as the number of edits increases while quality goes up with the number of edits for registered users."
Networking

Submission + - Attacking Criminal Networks on the Internet

Hugh Pickens writes: "Computer Scientists at Carnegie Mellon University are developing techniques to analyze and disrupt black markets on the internet, where criminals sell viruses, stolen data and attack services estimated to total more than $37 million for the seven-month period under study. To stem the flow of stolen credit cards and identity data, researchers have proposed two technical approaches to reduce the number of successful market transactions. One approach to disrupting the network is a slander attack where an attacker eliminates the verified status of a buyer or seller through false defamation. Another approach undercuts the cyber-crooks' network by creating a deceptive sales environment. "Just like you need to verify that individuals are honest on E-bay, online criminals need to verify that they are dealing with 'honest' criminals," says Jason Franklin, one of the researchers. "The scary thing about all this is that you do not have to be in the know to find black markets, they are easy to find, easy to join and just a mouse click away," Franklin added."
Security

Submission + - Disrupting Internet Black Markets

Hugh Pickens writes: "Computer Scientists at Carnegie Mellon University are developing techniques to analyze and disrupt online black markets, where internet attackers use well-developed business practices to sell viruses, stolen data and attack services. To stem the flow of stolen credit cards and identity data, researchers have developed an attack to undercut the cyber-crooks by creating a deceptive sales environment. "Just like you need to verify that individuals are honest on E-bay, online criminals need to verify that they are dealing with 'honest' criminals," says Jason Franklin, one of the researchers. The team has developed a technique to establish fake verified-status identities making it hard for buyers to identify the honest verified-status sellers. "By eliminating the verified status of the honest individuals, an attacker establishes a lemon market where buyers are unable to distinguish the quality of the goods or services," says Franklin."
Biotech

Submission + - What does it feel like to die?

Hugh Pickens writes: "The New Scientist reports that individuals who have had a brush with death can offer us some insight into what it feels like to die.

None of us can know the answers for sure until our own time comes, but the few individuals who have their brush with death interrupted by a last-minute reprieve can offer some intriguing insights. Advances in medical science, too, have led to a better understanding of what goes on as the body gives up the ghost. Whether as a result of a heart attack, drowning or suffocation, for example, people ultimately die because their neurons are deprived of oxygen, leading to cessation of electrical activity in the brain — the modern definition of biological death. If the flow of freshly oxygenated blood to the brain is stopped, through whatever mechanism, people tend to have about 10 seconds before losing consciousness. They may take many more minutes to die, though, with the exact mode of death affecting the subtleties of the final experience. If you can take the grisly details, read on for a brief guide to the many and varied ways death can suddenly strike.
"
Space

Submission + - The Dark Side of Iapetus 1

Hugh Pickens writes: "The difference in coloring between Iapetus' leading and trailing hemispheres is striking. NASA's Jet Propulsion Labs has just released a report on a bizarre "runaway" process that may explain the strange and dramatically two-toned appearance recently revealed in images collected during a close flyby by the Cassini spacecraft. Scientists believe that initially dark material on one side of Iapetus may have come from other moons orbiting Saturn in the opposite direction. Since Iapetus is locked in synchronous rotation about Saturn, as dusty material from the outer moons spiraled in and hit Iapetus head-on, the forward-facing side began to look different. Once the forward side began to darken, it absorbed more sunlight, its surface water evaporated, and vapor was transported from the dark side to the white side of Iapetus. Thermal segregation then proceeded in a runaway process as the the dark side lost its surface ice and got darker."
Google

Submission + - Google Hopes to Disaggregate Carriers with gPhone

Hugh Pickens writes: "The New York Times is publishing a story about Google's plan to loosen the carriers' control over their mobile phone networks in an effort to bring the dynamics of the PC-oriented Internet to the mobile Internet hoping that it can beat competitors in an open environment. The Google Phone or gPhone which is expected to be unveiled later this year will not compete with the iPhone but will help Google distribute their online services. Google intends to provide software that will be built into phones sold by many manufacturers and, unlike Microsoft's Windows Mobile, Google is not expected to charge phone makers a licensing fee for their software. Google will make its money brokering ads on the mobile phones and even envisions a free phone service one day supported entirely through ad revenue, people familiar with the matter say. But Google's plans are a double-edged sword for mobile operators. While Google's brand and services could help operators sign up more subscribers to data packages, on which they increasingly rely as voice revenue declines, operators have been wary about losing control over the mobile-ad market."
Biotech

Submission + - Scientists Poised to Create Artificial Life

Hugh Pickens writes: "Controversial DNA researcher Craig Venter, founder of Celera Genomics, which became famous for running a parallel version of the Human Genome Project of its own for commercial purposes, told the Guardian that his team of 20 top scientists led by the Nobel laureate Hamilton Smith has built a synthetic chromosome out of laboratory chemicals and is poised to announce the creation of the first new artificial life form on Earth. The team stitched together a chromosome that is 381 genes long and contains 580,000 base pairs of genetic code based on the bacterium Mycoplasma genitalium which the team pared down to the bare essentials needed to support life, removing a fifth of its genetic make-up. The team then transplanted the synthetic chromosome into a living bacterial cell where it is expected to take control of the cell and in effect become a new life form. The new life form will depend for its ability to replicate itself and metabolise on the molecular machinery of the cell into which it has been injected however, its DNA will be artificial, and it is the DNA that controls the cell and is credited with being the building block of life."
It's funny.  Laugh.

Submission + - New Nonstick Chewing Gum

Hugh Pickens writes: "About 600,000 metric tons of chewing gum are manufactured in the world every year and a large percentage ends up on streets and pavements becoming a pollution issue costing millions of dollars to remove. The MIT Technology Review reports that scientists have developed a new gum that easily comes off roads, shoes, and hair. Traditional chewing gum contains a gum base that is a mixture of synthetic petroleum-derived polymers, natural latex, resins, and waxes that are are hydrophobic — they stay away from water — and stick to the grease and grime on sidewalks. The new "Clean Gum" has polymers with a hydrophobic part that's wrapped inside a hydrophilic, or water-attracting, part. so a film of water can form around it making it easy to wash away with water. When researchers stuck the gum on sidewalks, rainwater or street cleaning would wash it off within 24 hours. Subjects in blind taste tests say that the gum tastes just as good as leading brands although the texture is slightly softer because the hydrophilic polymer interacts with saliva."
Biotech

Submission + - New Plastic Strong as Steel

Hugh Pickens writes: "Individual nano-size building blocks such as nanotubes, nanosheets and nanorods are ultrastrong but scientists have had difficulty transferring the strength of individual nanosheets to the entire material. Now researchers at the University of Michigan have created a new composite plastic made of layers of clay nanosheets and a water-soluble polymer with a machine they developed that builds materials layer by layer like mother of pearl, one of the toughest natural mineral-based materials. The layers are stacked like bricks, in an alternating pattern. "When you have a brick-and-mortar structure, any cracks are blunted by each interface," explained Nicholas Kotov adding that further development could lead to lighter, stronger armor for soldiers or police and their vehicles and could also be used in microelectromechanical devices, microfluidics, biomedical sensors and valves and unmanned aircraft."
Censorship

Submission + - Howl Against Censorship

Hugh Pickens writes: ""I saw the best minds of my generation destroyed by madness, starving hysterical naked," begins Allen Ginsberg's classic poem "Howl" now celebrating the 50th anniversary of a court ruling that found the poem had "redeeming social importance" and was thus not obscene. But Ginsberg, who died in 1997, might be surprised to learn that when Pacifica radio station WBAI considered broadcasting his poem to celebrate the anniversary, they decided against it fearing they could run afoul of the FCC's interpretation of indecency and incur bankrupting fines of up to $325,000 for every violation of its standards. "Since 2004 there's really been a sea change," said one first amendment lawyer. "The FCC made it clear it has a zero-tolerance policy for offensive language and images." In June the Second Circuit Court of Appeals in New York ruled against the FCC in the Janet Jackson Superbowl case, but the FCC has indicated that it will appeal to the Supreme Court. Meanwhile Ginsberg's protege Lawrence Ferlinghetti noted that the trial judge in the original Howl obscenity case once wrote: "Would there be any freedom of press or speech if one must reduce his vocabulary to vapid innocuous euphemism? An author should be real in treating his subject and be allowed to express his thoughts and ideas in his own words.""
Censorship

Submission + - Burma Shuts Down Internet 3

Hugh Pickens writes: "MIT Technology Review reports that in the aftermath of pro-democracy protests, Burma's military rulers have physically disconnected their country from the internet:

Last week — after images of the beatings of Buddhist monks and the killing of a Japanese photographer leaked out via the Internet — Burma's military rulers took the ultimate step, apparently physically disconnecting primary telecommunications cables in two major cities, in a drastic effort to stop the flow of information from Burma to the rest of the world. It didn't completely work: some bloggers apparently used satellite links or cellular phone services to get information outside the country.
One Burmese blogger reported last week that "Myanmar main ISP has been shut down by so-called "maintenance reasons" and most of the telecommunication services have been cut off or tapped. ""
Space

Submission + - Weather on Titan Is Tropical in Nature

Hugh Pickens writes: "Climate researchers Ray Pierrehumbert and Jonathan Mitchell at the University of Chicago say that Titan, the only moon in the solar system large enough to support an atmosphere, has many of the same weather features as Earth, but with completely different substances that work at temperatures that plunge down to minus 170 degrees Celsius. Pierrehumbert and Mitchell call Titan's climate tropical, a climate that is warm to hot and wet year-round, because on Titan methane assumes the role of water and exists in enough abundance to condense into rain and form puddles on the surface. Titan's tropical nature means that scientists can observe the behavior of its clouds using theories they've developed to understand Earth's tropics. For example, Titan's atmosphere produces an updraft where surface winds converge to lift evaporated methane up to cooler temperatures and lower pressures, where much of it condenses and forms clouds, "a well-known feature on Earth called an ITCZ, the inter-tropical convergence zone," Mitchell says."
Biotech

Submission + - Mutant Algae to Fuel Cars of Tomorrow?

Hugh Pickens writes: "Algae has long been known as a promising source of biodiesel, however algae also produce a small amount of hydrogen during photosynthesis. The MIT Technology Review reports that now researchers have created a mutant algae that makes better use of sunlight to increase the amount of hydrogen that the algae produce. In a commercial bioreactor, the top layers of algae absorb most of the sunlight but can only use a fraction of it. Anastasios Melis and his team at the University of California have manipulated the genes that control the amount of chlorophyll in the algae's chloroplasts reducing the chlorophyll so that the algae absorb less sunlight. This lets more light penetrate into the deeper algae layers so that more cells use the sunlight to make hydrogen. Although the process is still at least five years from being used for hydrogen generation, Melis estimates that if 50% of capacity of the photosynthesis of the algae could be directed toward hydrogen production, an acre could produce 40 kilograms of hydrogen per day bringing the cost of producing hydrogen to $2.80 a kilogram. At this price, hydrogen could compete with gasoline, since a kilogram of hydrogen is equivalent in energy to a gallon of gasoline."
Power

Submission + - First New Nuclear Plant in US in 30 years

Hugh Pickens writes: "With backing from the White House and congressional leaders, and subsidies like the $500 million in risk insurance from the Department of Energy, the nuclear industry is experiencing a revival in the US. Scientific American reports that this week NRG Energy filed an application for the first new nuclear power plant in the US in thirty years to build two advanced boiling water reactors (ABWR) at its South Texas nuclear power plant site doubling the 2700 megawatts presently generated at the facility. The ABWR, based on technology already operating in Japan, works by using the heat generated by the controlled splitting of uranium atoms in fuel rods to directly boil water into steam to drive turbines producing electricity. Improvements over previous designs include removing water circulation pipes that could rupture and accidentally drain water from the reactor, exposing the fuel rods to a potential meltdown, and fewer pumps to move the water through the system. NRG projects it will spend $6 billion constructing the two new reactors and hopes to have the first unit online by 2014."

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