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Smaller is Stronger -- Now Scientists Know Why |
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Topic: Science |
5:37 am EST, Feb 21, 2008 |
As structures made of metal get smaller — as their dimensions approach the micrometer scale (millionths of a meter) or less — they get stronger. Scientists discovered this phenomenon 50 years ago while measuring the strength of tin "whiskers" a few micrometers in diameter and a few millimeters in length. Many theories have been proposed to explain why smaller is stronger, but only recently has it become possible to see and record what's actually happening in tiny structures under stress.
Read on the post is very detailed ... Does this apply to humans too? Smaller is Stronger -- Now Scientists Know Why |
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Feeling the Heat: Berkeley Researchers Make Thermoelectric Breakthrough in Silicon Nanowires |
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Topic: Science |
5:35 am EST, Feb 21, 2008 |
Energy now lost as heat during the production of electricity could be harnessed through the use of silicon nanowires synthesized via a technique developed by researchers with the U.S. Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) at Berkeley. The far-ranging potential applications of this technology include DOE’s hydrogen fuel cell-powered “Freedom CAR,” and personal power-jackets that could use heat from the human body to recharge cell-phones and other electronic devices. Science image spacer image Rough silicon nanowires synthesized by Berkeley Lab researchers demonstrated high performance thermoelectric properties even at room temperature when connected between two suspended heating pads. In this illustration, one pad serves as the heat source (pink), the other as the sensor. “This is the first demonstration of high performance thermoelectric capability in silicon, an abundant semiconductor for which there already exists a multibillion dollar infrastructure for low-cost and high-yield processing and packaging,” said Arun Majumdar, a mechanical engineer and materials scientist with joint appointments at Berkeley Lab and UC Berkeley, who was one of the principal investigators behind this research.
Feeling the Heat: Berkeley Researchers Make Thermoelectric Breakthrough in Silicon Nanowires |
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Research News: Debut of TEAM 0.5, the World's Best Microscope |
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Topic: Science |
5:34 am EST, Feb 21, 2008 |
TEAM 0.5, the world's most powerful transmission electron microscope — capable of producing images with half‑angstrom resolution (half a ten-billionth of a meter), less than the diameter of a single hydrogen atom — has been installed at the Department of Energy's National Center for Electron Microscopy (NCEM) at Lawrence Berkeley National Laboratory. Science image spacer image TEAM 0.5, the world's best transmission electron microscope, is being assembled at the National Center for Electron Microscopy. (Photo Roy Kaltschmidt, Berkeley Lab CSO) "We have beam down the column," announced Uli Dahmen of Berkeley Lab's Materials Sciences Division, who is head of NCEM and director of DOE's collaborative TEAM Project, when the TEAM 0.5 microscope first delivered its ultrabright electron beam at Berkeley Lab in late December. The TEAM Project (TEAM stands for Transmission Electron Aberration-corrected Microscope) is led by Berkeley Lab in a collaboration with DOE's Argonne and Oak Ridge National Laboratories, the Frederick Seitz Materials Laboratory of the University of Illinois, and two private companies specializing in electron microscopy, the FEI Company headquartered in Portland, Oregon, and CEOS of Heidelberg, Germany. Now that TEAM 0.5's basic systems are operational, additional components and facilities are being completed and tuned, including a state-of-the-art control room display that shows the sample under the microscope on a flat panel resembling a wide-screen, high-definition TV. After a long series of rigorous tests and adjustments, TEAM 0.5 will become available to outside users by October, 2008.
Research News: Debut of TEAM 0.5, the World's Best Microscope |
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Why Did The Tornado Skip Nashville & Davidson County - A Meteorologist Theory |
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Topic: Science |
2:32 am EST, Feb 17, 2008 |
I know alot of people are probably wondering why the tornado lifted as it approached Davidson County Tuesday Night February 5th, 2008. I'm not sure that we will ever know the complete answer but here are my thoughts as what may have caused it to lift as it moved through Davidson County. Over the years there have been alot of studies of supercell tornadoes and their environment. One concept that I think could have played a role is that of the Rear Flank Downdraft. The Rear Flank Downdraft is a prominent feature of tornadic supercells. The Rear Flank Downdraft forms on the backside of the supercell storm and can be observed visually as a clear slot. The Rear Flank Downdraft is a region of dry air wrapping around the back of a mesocyclone in a supercell thunderstorm. These areas of descending air are essential in the production of supercellular tornadoes. Warm Rear Flank Downdrafts promote tornadoes, while Cold Rear Flank Downdrafts discourage them. Cold air downbursts impinging upon the tornado as it approached Davidson County would have caused the tornado funnel to tilt increasingly from the vertical, becoming a funnel cloud as it lifted above the ground and possibly dissipating over Davidson County to only reform in Sumner County a short while later as warmer air got entrained. Spotter reports of strong, warm inflow winds Southeast of the wall cloud (area of strongest updraft) would suggest a higher tornado risk than the case where the wall cloud is undercut by cold air outflow. -Bobby Boyd Meteorologist NWS/Nashville, TN
Why Did The Tornado Skip Nashville & Davidson County - A Meteorologist Theory |
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Scientists Feel Miscast in Film on Life’s Origin |
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Topic: Science |
7:03 pm EST, Feb 8, 2008 |
A few months ago, the evolutionary biologist Richard Dawkins received an e-mail message from a producer at Rampant Films inviting him to be interviewed for a documentary called “Crossroads.” The film, with Ben Stein, the actor, economist and freelance columnist, as its host, is described on Rampant’s Web site as an examination of the intersection of science and religion. Dr. Dawkins was an obvious choice. An eminent scientist who teaches at Oxford University in England, he is also an outspoken atheist who has repeatedly likened religious faith to a mental defect. But now, Dr. Dawkins and other scientists who agreed to be interviewed say they are surprised — and in some cases, angered — to find themselves not in “Crossroads” but in a film with a new name and one that makes the case for intelligent design, an ideological cousin of creationism. The film, “Expelled: No Intelligence Allowed,” also has a different producer, Premise Media. The film is described in its online trailer as “a startling revelation that freedom of thought and freedom of inquiry have been expelled from publicly-funded high schools, universities and research institutions.” According to its Web site, the film asserts that people in academia who see evidence of a supernatural intelligence in biological processes have unfairly lost their jobs, been denied tenure or suffered other penalties as part of a scientific conspiracy to keep God out of the nation’s laboratories and classrooms. Mr. Stein appears in the film’s trailer, backed by the rock anthem “Bad to the Bone,” declaring that he wants to unmask “people out there who want to keep science in a little box where it can’t possibly touch God.” If he had known the film’s premise, Dr. Dawkins said in an e-mail message, he would never have appeared in it. “At no time was I given the slightest clue that these people were a creationist front,” he said. Eugenie C. Scott, a physical anthropologist who heads the National Center for Science Education, said she agreed to be filmed after receiving what she described as a deceptive invitation. “I have certainly been taped by people and appeared in productions where people’s views are different than mine, and that’s fine,” Dr. Scott said, adding that she would have appeared in the film anyway. “I just expect people to be honest with me, and they weren’t.”
More FUD.. Scientists Feel Miscast in Film on Life’s Origin |
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The Flight 800 Investigation |
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Topic: Science |
1:26 am EST, Feb 2, 2008 |
Glen Schulze, a noted expert witness in Aviation Accident Tape Analysis, has completed an extensive analysis of the limited data released by the NTSB on the Flight Data Recorder (FDR), its numerous revisions by the NTSB and a recently obtained segment of the analog tape waveform at the end of the tape. In this detailed analysis he proves beyond any doubt that the NTSB is withholding data from the end of the FDR tape. The analysis shows that the printed data released by the NTSB, which was revised several times, does not match the analog tape segment waveform received under the Freedom of Information Act. Glen's analysis shows that there could be up to 4 seconds missing from the end of the tape, or in the alternative, the end of the tape was edited to remove some data, causing the difference between the printed data and the waveform data. Although this is very technical reading, it is worth a look. He supports his analysis with numerous exhibits from the NTSB docket public record. The final graphic shows a transient spike, which is consistent with electronic editing. This new information is troubling and demands and explanation from the NTSB. Perhaps we will finally get one with the new Administration.
The Flight 800 Investigation |
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Pleasant Hill Starlight Observatory Clear Sky Clock |
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Topic: Science |
9:09 pm EST, Jan 27, 2008 |
It's the astronomers forecast. At a glance, it shows when it will be cloudy or clear for up to the next two days. It's a prediction of when Pleasant Hill Starlight Observatory, TN, will have good weather for astronomical observing. The forecast data comes from those very cool guys at the Canadian Meteorological Center. CMC's numerical weather forecasts are unique because they are specifically designed for astronomers. But they have 763 forecast maps. It can be a chore to find the one you want. So, I (Attilla Danko) wrote a script to generate the images like the one above which summarizes CMC's forecast images just for Pleasant Hill Starlight Observatory and the surroundings out to about 10 miles. There are also clocks for 3308 other locations.
This is one of the net oddities that might be useful... Pleasant Hill Starlight Observatory Clear Sky Clock |
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US Satellite could plummet to Earth |
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Topic: Science |
8:43 pm EST, Jan 27, 2008 |
Officials speaking on condition of anonymity said the satellite had lost power and propulsion, and could contain hazardous materials. The White House said it was monitoring the situation. A spokesman said "numerous" satellites had come out of orbit and fallen back to Earth harmlessly over the years. "We are looking at potential options to mitigate any possible damage this satellite may cause," said Gordon Johndroe, who speaks for the US National Security Council. Questioned by The Associated Press, he would not be drawn on whether the US would try to destroy the satellite, perhaps with a missile. An unnamed official quoted by AP said the US government was keeping lawmakers and other countries abreast of the situation. Fuel hazard The satellite contains the rocket fuel hydrazine, a government official told AP on condition of anonymity. A colourless liquid with an ammonia-like odour, the fuel is a toxic chemical and can cause harm to anyone who comes in contact with it. John Pike, director of the defence research group GlobalSecurity.org, said an uncontrolled re-entry could risk exposure of US secrets. Spy satellites typically are disposed of through a controlled re-entry into the ocean so that no one else can access the spacecraft, he was quoted by AP as saying. The military expert believes that shooting the satellite down would create debris that would then re-enter the atmosphere and burn up or hit the ground. In his estimate, the satellite weighs about 20,000 pounds (9,072kg) and is the size of a small bus. It is possible, he adds, that this one died as long as a year ago and is just now getting ready to re-enter the atmosphere. Another expert, Jeffrey Richelson of the National Security Archive, said the satellite is probably a photo reconnaissance satellite. Into the ocean AP notes that the largest uncontrolled re-entry by a US space agency (Nasa) craft was Skylab. The 78-tonne abandoned space station fell from orbit in 1979. Its debris dropped harmlessly into the Indian Ocean and across a remote section of western Australia, the US news agency says. In 2002, officials believe debris from a 7,000-pound (3,175-kg) science satellite hit the Earth's atmosphere. It rained down over the Gulf, a few thousand miles from where they first predicted it would crash.
Lookout! US Satellite could plummet to Earth |
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Researchers Take Step Toward Synthetic Life |
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Topic: Science |
1:06 am EST, Jan 25, 2008 |
Taking a significant step toward the creation of synthetic forms of life, researchers reported Thursday that they had manufactured the entire genome of a bacterium by stitching together its chemical components. Scientists had previously constructed the complete DNA of viruses, but this is the first time it has been done for bacteria, which are far more complex. The genome is more than 10 times as long as the longest piece of DNA ever synthesized. The feat is a watershed for the emerging field called synthetic biology, which involves the design of organisms to perform particular tasks, like making biofuels. Synthetic biologists envision being able to design an organism on a computer, press the “print” button to have the necessary DNA made and then put that DNA into a cell to produce a custom-made creature. “What we are doing with the synthetic chromosome is going to be the design process of the future,” said J. Craig Venter, the boundary-pushing gene scientist. Dr. Venter assembled the team that made the bacterial genome as part of his well-publicized quest to create the first synthetic organism. The work was published online Thursday by the journal Science.
Researchers Take Step Toward Synthetic Life |
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Does Radiation Exposure Make Boys Disappear? |
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Topic: Science |
7:39 pm EST, Jan 17, 2008 |
As a rule, more boys than girls are born. But in November 1986 in the eastern regions of the Czech Republic, the reverse was true – more girls than boys. It appears that radiation exposure released by the Chernobyl nuclear accident in April 1986, brought to earth by rain over the area, increased radiation exposure. Fetuses that were approximately three months old at the time appear to have been effected, resulting in a reduction of newborn boys six months later. According to the authors, “A greater vulnerability is known of male fetuses to prenatal damage by environmental stress. That is why the long-standing higher male birth fraction is considered as a sensitive indicator of stability and health in human reproduction. In this case, the authors hypothesize that “a large release of iodine-131 and other shorter-lived isotopes of iodine resulted in damage of the thyroid gland in fetuses and/or their mothers. A serious damage of the thyroid gland in three months old fetuses in end of April - beginning of May by radioiodine might be one of the main reasons for their loss detected as a decrease in male birth fraction in November 1986.”
Does Radiation Exposure Make Boys Disappear? |
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