My Love Of Shortwave Radio - 1 views
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anonymous on 23 Aug 12How I got interested in shortwave and ham radio by building a crystal radio kit as a child.
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SETILive - 0 views
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SETILive is taking the Search for Extraterrestrial Intelligence (SETI) directly to you by presenting radio frequency signals LIVE from the SETI Institute's Allen Telescope Array (ATA) while it's pointed at stars that, based on Kepler exoplanet discoveries, have the best chances of being home to an alien civilization. We'll also be putting you "in the loop" where if enough of you see a potential extraterrestrial (ET) signal in the same data, then within minutes, the ATA will be interrupted and sent back to take a second look. The data you see will be from frequencies where human-made Radio Frequency Interference (RFI) crowds them and we believe the human eye will have a better chance than SETI's computer algorithms to find ET signals there.
Quantum Computers and Parallel Universes - YouTube - 0 views
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Complete video at: http://fora.tv/2009/05/23/Marcus_Chown_in_Conversation_with_Fred_Watson Marcus Chown, author of Quantum Theory Cannot Hurt You: A Guide to the Universe, discusses the mechanics behind quantum computers, explaining that they function by having atoms exist in multiple places at once. He predicts that quantum computers will be produced within 20 years. ----- The two towering achievements of modern physics are quantum theory and Einsteins general theory of relativity. Together, they explain virtually everything about the world in which we live. But almost a century after their advent, most people havent the slightest clue what either is about. Radio astronomer, award-winning writer and broadcaster Marcus Chown talks to fellow stargazer Fred Watson about his book Quantum Theory Cannot Hurt You. - Australian Broadcasting Corporation Marcus Chown is an award-winning writer and broadcaster. Formerly a radio astronomer at the California Institute of Technology, he is now cosmology consultant of the weekly science magazine New Scientist. The Magic Furnace, Marcus' second book, was chosen in Japan as one of the Books of the Year by Asahi Shimbun. In the UK, the Daily Mail called it "a dizzy page-turner with all the narrative devices you'd expect to find in Harry Potter". His latest book is called Quantum Theory Cannot Hurt You.
Chromoscope - View the Universe in different wavelengths - 0 views
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Chromoscope lets you explore our Galaxy (the Milky Way) and the distant Universe in a range of wavelengths from gamma-rays to the longest radio waves.
Patricia Springfield: Technology and Informal Education: What Is Taught, What Is Learned - 0 views
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"Formal education must adapt to these changes, taking advantage of new strengths in visual-spatial intelligence and compensating for new weaknesses in higher-order cognitive processes: abstract vocabulary, mindfulness, reflection, inductive problem solving, critical thinking, and imagination. These develop through the use of an older technology, reading, which, along with audio media such as radio, also stimulates imagination. Informal education therefore requires a balanced media diet using each technology's specific strengths in order to develop a complete profile of cognitive skills. "
How to break into science writing using your blog and social media (#sci4hels) | The SA... - 0 views
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"It is important to be aware that 20th century media ecosystem is a very unusual aberration in the way people communicated throughout history. Means of production were expensive. Very few people could afford to own printing presses, radio and TV studios, etc. Running all that complicated equipment required technical expertise and professional training. Thus media became locked up in silos, hierarchical, broadcast-only with little-to-none (and then again centrally controlled) means for feedback. There was a wealthy, vocal minority that determined what was news, and how to frame it, and the vast majority was consuming the news in silence"
WWF Species Tracker - All species - - 0 views
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"WWF supports research on wildlife populations throughout the Arctic and around the world. Using radio devices, which transmit location data by satellite, researchers can follow individual animals to learn more about their habitats, behaviour and migration patterns. The researchers share this data with WWF regularly, so check back often to see where the animals are going!"
Moon may reveal elusive cosmic neutrinos - New Scientist - 0 views
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Hunting for the elusive neutrino typically involves treks to Antarctica, the Mediterranean, and Lake Baikal. But a growing number of projects are looking for the most energetic neutrinos by aiming radio telescopes at the moon.
Explained: Gallager codes - 0 views
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"In the 1948 paper that created the field of information theory, MIT grad (and future professor) Claude Shannon threw down the gauntlet to future generations of researchers. In those predigital days, communications channels - such as phone lines or radio bands - were particularly susceptible to the electrical or electromagnetic disruptions known as "noise.""
GPS Jamming Devices Pose Many Threats (w/ Video) - 0 views
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GPS jammers send out a radio signal that’s the same frequency as the satellite signal. Since GPS satellite signals are weak, a GPS jamming device that puts out approximately 2 watts is sufficient to disrupt a GPS signal in a vehicle that’s approximately within 10 feet of the device. This leaves the in-vehicle system unable to establish its position and report back to a GPS tracking center, where the vehicle is registered. There are also fears that terrorists can use these devices to disrupt air traffic and cause severe safety and economic damage to the US. More powerful jammers could disrupt GPS signals in close proximity of airports, causing safety concerns. Our military overseas use GPS extensively to record their position as well as the position of the enemy. With GPS jamming devices in the hands of our enemy, U.S. and allied forces can be severely impacted when launching ground and air-strikes.
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The latest GPS jamming devices are now being used by car thieves in the UK to render stolen cars and trucks undetectable by law enforcement. These devices also pose a threat to airlines and US military overseas.
Peak Oil and a Changing Climate | The Nation - 2 views
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Peak Oil is the point at which petroleum production reaches its greatest rate just before going into perpetual decline. In "Peak Oil and a Changing Climate," a new video series from The Nation and On The Earth productions, radio host Thom Hartmann explains that the world will reach peak oil within the next year if it hasn't already. As a nation, the United States reached peak oil in 1974, after which it became a net oil importer. Bill McKibben, Noam Chomsky, Nicole Foss, Richard Heinberg and the other scientists, researchers and writers interviewed throughout "Peak Oil and a Changing Climate" describe the diminishing returns our world can expect as it deals with the consequences of peak oil even as it continues to pretend it doesn't exist. These experts predict substantially increased transportation costs, decreased industrial production, unemployment, hunger and social chaos as the supplies of the fuels on which we rely dwindle and eventually disappear. Chomsky urges us to anticipate the official response to peak oil based on how corporations, news organizations and other institutions have responded to global warming: obfuscation, spin and denial. James Howard Kunstler says that we cannot survive peak oil unless we "come up with a consensus about reality that is consistent with the way things really are." This documentary series hopes to help build that consensus. Click here to watch the introductory video, and check back here for new videos each Wednesday.
Dr. Daniel G. Nocera - YouTube - 0 views
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The supply of secure, clean, sustainable energy is arguably the most important scientific and technical challenge facing humanity in the 21st century. Rising living standards of a growing world population will cause global energy consumption to double by mid-century and triple by the end of the century. Even in light of unprecedented conservation, the additional energy needed is simply not attainable from long discussed sources these include nuclear, biomass, wind, geothermal and hydroelectric. The global appetite for energy is simply too much. Petroleum-based fuel sources (i.e., coal, oil and gas) could be increased. However, deleterious consequences resulting from external drivers of economy, the environment, and global security dictate that this energy need be met by renewable and sustainable sources. The dramatic increase in global energy need is driven by 3 billion low-energy users in the non-legacy world and by 3 billion people yet to inhabit the planet over the next half century. The capture and storage of solar energy at the individual level personalized solar energy drives inextricably towards the heart of this energy challenge by addressing the triumvirate of secure, carbon neutral and plentiful energy. This talk will place the scale of the global energy issue in perspective and then discuss how personalized energy (especially for the non-legacy world) can provide a path to a solution to the global energy challenge. Daniel G. Nocera is the Henry Dreyfus Professor of Energy at the Massachusetts Institute of Technology, Director of the Solar Revolutions Project and Director of the Eni Solar Frontiers Center at MIT. His group pioneered studies of the basic mechanisms of energy conversion in biology and chemistry. He has recently accomplished a solar fuels process that captures many of the elements of photosynthesis outside of the leaf. This discovery sets the stage for a storage mechanism for the large scale, distributed, deployment of solar energy. He has b
Human cells exhibit foraging behavior like amoebae and bacteria - 0 views
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"As far as we can tell, this is the first time this type of behavior has been reported in cells that are part of a larger organism," says Peter T. Cummings, John R. Hall Professor of Chemical Engineering, who directed the study that is described in the March 10 issue of the Public Library of Science journal PLoS ONE. The discovery was the unanticipated result of a study the Cummings group conducted to test the hypothesis that the freedom with which different cancer cells move - a concept called motility - could be correlated with their aggressiveness: That is, the faster a given type of cancer cell can move through the body the more aggressive it is. "Our results refute that hypothesis—the correlation between motility and aggressiveness that we found among three different types of cancer cells was very weak," Cummings says. "In the process, however, we began noticing that the cell movements were unexpectedly complicated." Then the researchers' interest was piqued by a paper that appeared in the February 2008 issue of the journal Nature titled, "Scaling laws of marine predator search behaviour." The paper contained an analysis of the movements of a variety of radio-tagged marine predators, including sharks, sea turtles and penguins. The authors found that the predators used a foraging strategy very close to a specialized random walk pattern, called a Lévy walk, an optimal method for searching complex landscapes. At the end of the paper's abstract they wrote, "...Lévy-like behaviour seems to be widespread among diverse organisms, from microbes to humans, as a 'rule' that evolved in response to patchy resource distributions." This gave Cummings and his colleagues a new perspective on the cell movements that they were observing in the microscope. They adopted the basic assumption that when mammalian cells migrate they face problems, such as efficiently finding randomly distributed targets like nutrients and growth factors, that are analogous to those faced by single-celled organisms foraging for food. With this perspective in mind, Alka Potdar, now a post-doctoral fellow at Case Western Reserve University and the Cleveland Clinic, cultured cells from three human mammary epithelial cell lines on two-dimensional plastic plates and tracked the cell motions for two-hour periods in a "random migration" environment free of any directional chemical signals. Epithelial cells are found throughout the body lining organs and covering external surfaces. They move relatively slowly, at about a micron per minute which corresponds to two thousandths of an inch per hour. When Potdar carefully analyzed these cell movements, she found that they all followed the same pattern. However, it was not the Lévy walk that they expected, but a closely related search pattern called a bimodal correlated random walk (BCRW). This is a two-phase movement: a run phase in which the cell travels primarily in one direction and a re-orientation phase in which it stays in place and reorganizes itself internally to move in a new direction. In subsequent studies, currently in press, the researchers have found that several other cell types (social amoeba, neutrophils, fibrosarcoma) also follow the same pattern in random migration conditions. They have also found that the cells continue to follow this same basic pattern when a directional chemical signal is added, but the length of their runs are varied and the range of directions they follow are narrowed giving them a net movement in the direction indicated by the signal.
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When cells move about in the body, they follow a complex pattern similar to that which amoebae and bacteria use when searching for food, a team of Vanderbilt researchers have found. The discovery has a practical value for drug development: Incorporating this basic behavior into computer simulations of biological processes that involve cell migration, such as embryo development, bone remodeling, wound healing, infection and tumor growth, should improve the accuracy with which these models can predict the effectiveness of untested therapies for related disorders, the researchers say.
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