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Science

Ask Slashdot: What Are the Most Dangerous Lines of Scientific Inquiry? 456

Posted by samzenpus
from the don't-even-ask dept.
gbrumfiel writes "The battle over whether to publish research into mutant bird flu got editors over at Nature News thinking about other potentially dangerous lines of scientific inquiry. They came up with a non-definitive list of four technologies with the potential to do great good or great harm: Laser isotope enrichment: great for making medical isotopes or nuclear weapons. Brain scanning: can help locked-in patients to communicate or a police state to read minds. Geoengineering: could lessen the effects of climate change or undermine the political will to fight it. Genetic screening of embryos: could spot genetic disorders in the womb or lead to a brave new world of baby selection. What would Slashdotters add to the list?"
Earth

Organics Can't Match Conventional Farm Yields 452

Posted by timothy
from the that's-what-they-want-you-to-think dept.
scibri writes "A comprehensive analysis published in Nature (abstract) suggests that organic farming could supply needs in some circumstances. But yields are lower than in conventional farming, so producing the bulk of the globe's diet will still require chemical fertilizers and pesticides. The meta-analysis reviewed 66 studies comparing the yields of 34 different crop species in organic and conventional farming systems. The researchers included only studies that assessed the total land area used, allowing them to compare crop yields per unit area. Many previous studies that have showed large yields for organic farming ignore the size of the area planted — which is often bigger than in conventional farming. Crop yields from organic farming are as much as 34% lower than those from comparable conventional farming practices, though in some cases, notably with strawberries and soybeans, the gap is as small as 3%."
NASA

Is Extraterrestrial Life More Whimsical Than Plausible? 344

Posted by timothy
from the eeeehhhlliott dept.
coondoggie writes "Princeton University researchers are throwing some cold water on the hot notion that astrobiologists and other scientists expect to one day find life on other planets. Recent discoveries of planets similar to Earth in size and proximity to the planets' respective suns have sparked scientific and public excitement about the possibility of also finding Earth-like life on those worlds, but the expectation that life — from bacteria to sentient beings — has or will develop on other planets as on Earth might be based more on optimism than scientific evidence."
Math

Study Suggests the Number-Line Concept Is Not Intuitive 404

Posted by samzenpus
from the learning-to-count dept.
An anonymous reader writes "The Yupno people of New Guinea have provided clues to the origins of the number-line concept, and suggest that the familiar concept of time may be cultural as well. From the article: 'Tape measures. Rulers. Graphs. The gas gauge in your car, and the icon on your favorite digital device showing battery power. The number line and its cousins – notations that map numbers onto space and often represent magnitude – are everywhere. Most adults in industrialized societies are so fluent at using the concept, we hardly think about it. We don't stop to wonder: Is it 'natural'? Is it cultural? Now, challenging a mainstream scholarly position that the number-line concept is innate, a study suggests it is learned."
Science

Insects Develop Pesticide Resistance Through Symbiosis With Gut Flora 144

Posted by samzenpus
from the with-a-little-help-from-my-little-friends dept.
First time accepted submitter blinkin247 writes "The indiscriminate spraying of pesticides has probably caused as many problems as it has solved, but here's one that was not expected: some bacteria have decided that insecticide is a very tasty meal. Unfortunately for us, one of the strains of bacteria that has evolved the ability to digest the toxin happens to be able to find a home in an insect's gut. When it does so, it provides the insect with resistance."
Science

Solar Cells That Emit Light Break Efficiency Record 139

Posted by samzenpus
from the shine-on dept.
benfrog writes "Researchers at the University of California-Berkeley say they have come up with a counter-intuitive way of making solar cells more efficient — making them emit light. In a press release the scientists claim to be the first to demonstrate that the better solar cells are at emitting photons (the more LED-like they are), the more efficient they are at generating electricity. However, 'unlike an LED, the electrons in a solar cell are absorbing photons from an exterior source as well as emitting their own.'"
Space

World's Largest Digital Camera Project Passes Critical Milestone 73

Posted by samzenpus
from the have-some-funding dept.
An anonymous reader writes in with a link about the progress of one of the coolest astronomy projects around. "A 3.2 billion-pixel digital camera designed by SLAC National Accelerator Laboratory is now one step closer to reality. The Large Synoptic Survey Telescope camera, which will capture the widest, fastest and deepest view of the night sky ever observed, has received 'Critical Decision 1' approval by the U.S. Department of Energy (DOE) to move into the next stage of the project. The Large Synoptic Survey Telescope (LSST) will survey the entire visible sky every week, creating an unprecedented public archive of data – about 6 million gigabytes per year, the equivalent of shooting roughly 800,000 images with a regular eight-megapixel digital camera every night, but of much higher quality and scientific value. Its deep and frequent cosmic vistas will help answer critical questions about the nature of dark energy and dark matter and aid studies of near-Earth asteroids, Kuiper belt objects, the structure of our galaxy and many other areas of astronomy and fundamental physics."
Moon

NASA and Astrobotic Investigating Ice Hunting Mission to the Moon 46

Posted by Unknown Lamer
from the repurposed-as-newt's-moon-scooter dept.
Zothecula writes, quoting Gizmodo "While the Moon may or may not contain life forms, precious metals or even green cheese, recent satellite missions have indicated that it does nonetheless contain something that could prove quite valuable — water ice. NASA has estimated that at least 650 million tons (600 million tonnes) of the stuff could be deposited in craters near the Moon's north pole alone. If mined, it could conceivably serve as a source of life support for future lunar bases, or it could be used to produce fuel for spacecraft stopping at a "lunar gas station." Before any mining can happen, however, we need to learn more about the ice. That's why NASA has contracted Pittsburgh-based Astrobotic Technology to determine if its Polaris rover robot could be used for ice prospecting."
It's funny.  Laugh.

Travelling Salesman, Thriller Set In a World Where P=NP 165

Posted by Unknown Lamer
from the very-serious-faces-throughout dept.
mikejuk writes with this excerpt from I Programmer: "A movie that features science and technology is always welcome, but is it not often we have one that focuses on computer science. Travelling Salesman is just such a rare movie. As you can guess from its name, it is about the Travelling Salesman problem, more precisely about the P=NP question. Written and directed by Timothy Lanzone, and produced by Fretboard Pictures, it should premiere on June 16. As the blurb to the movie trailer says: 'Travelling Salesman is an intellectual thriller about four of the world's smartest mathematicians hired by the U.S. government to solve the most elusive problem in computer science history — P vs. NP. The four have jointly created a "system" which could be the next major advancement for humanity or the downfall of society.'"
Censorship

Avian Flu Researcher Backs Down On Plan To Defy Publishing Ban 54

Posted by Unknown Lamer
from the would-like-to-see-family-live dept.
ananyo writes "Ron Fouchier, a researcher at the Erasmus Medical Center in Rotterdam, the Netherlands, whose work on the H5N1 avian flu virus has been embroiled in controversy, has now agreed to apply for an export permit to submit his work to the journal Science. Fouchier's paper is one of two reporting the creation of forms of the H5N1 virus capable of spreading between mammals. The other, by Yoshihiro Kawaoka of the University of Wisconsin, Madison, and the University of Tokyo, and his colleagues, has already been submitted to Nature. Fouchier had said last week that he intended to defy the government and submit the work to Science without seeking the export permit that the Dutch government says is required." In related news, renek noted that the U.S. NIH director supports publishing the papers in full.
Medicine

Mad Cow Disease Confirmed In California 274

Posted by Soulskill
from the denny-crane dept.
New submitter wave9x writes "The United States Department of Agriculture confirmed today that the nation's fourth case of bovine spongiform encephalopathy, sometimes referred to as 'mad cow disease' was found in a dairy cow in California. The animal has been euthanized and the carcass is being being held under State authority at a rendering facility in California and will be destroyed."
Biotech

Scientists Clone Sheep With 'Good' Fat 233

Posted by Soulskill
from the pulling-the-wool-over-your-stomach's-eyes dept.
redletterdave writes "Chinese scientists have cloned a genetically modified sheep containing a 'good' type of fat found naturally in nuts, seeds, fish and leafy greens that helps reduce the risk of heart attacks and cardiovascular disease. The gene, which is linked to the production of polyunsaturated fatty acids, was inserted into a donor cell taken from the ear of a Chinese Merino sheep. The cell was then inserted into an unfertilized egg and implanted into the womb of a surrogate sheep. With any luck, this process could be replicated in the future to clone more animals for safe and healthy consumption."
Medicine

Childhood Stress Leaves Genetic Scars 334

Posted by Soulskill
from the stories-told-in-base-pairs dept.
sciencehabit writes "Traumatic experiences in early life can leave emotional scars. But a new study suggests that violence in childhood may leave a genetic mark as well. Researchers have found that children who are physically abused and bullied tend to have shorter telomeres — structures at the tips of chromosomes whose shrinkage has been linked to aging and disease."
Earth

How Nearby Supernovae Affected Life On Earth 109

Posted by Soulskill
from the made-of-star-stuff dept.
sycodon writes with news of research into how nearby supernovae affected the development of life on Earth. "[Professor Henrik Svensmark] found that the changing frequency of nearby supernovae seems to have strongly shaped the conditions for life on Earth. Whenever the Sun and its planets have visited regions of enhanced star formation in the Milky Way Galaxy, where exploding stars are most common, life has prospered. Prof. Svensmark remarks in the paper, "The biosphere seems to contain a reflection of the sky, in that the evolution of life mirrors the evolution of the Galaxy.' ... The data also support the idea of a long-term link between cosmic rays and climate, with these climatic changes underlying the biological effects. And compared with the temperature variations seen on short timescales as a consequence of the Sun's influence on the influx of cosmic rays, the heating and cooling of the Earth due to cosmic rays varying with the prevailing supernova rate have been far larger.""
Science

Quantum Experiment Shows Effect Before Cause 465

Posted by Soulskill
from the enjoy-the-headache dept.
steveb3210 writes "Physicists have demonstrated that making a decision about whether or not to entangle two photons can be made after you've already measured the states of the photons." Here's the article's description of the experiment: 'Two independent sources (labeled I and II) produce pairs of photons such that their polarization states are entangled. One photon from I goes to Alice, while one photon from II is sent to Bob. The second photon from each source goes to Victor. Alice and Bob independently perform polarization measurements; no communication passes between them during the experiment—they set the orientation of their polarization filters without knowing what the other is doing. At some time after Alice and Bob perform their measurements, Victor makes a choice (the "delayed choice" in the name). He either allows his two photons from I and II to travel on without doing anything, or he combines them so that their polarization states are entangled. A final measurement determines the polarization state of those two photons. ... Ma et al. found to a high degree of confidence that when Victor selected entanglement, Alice and Bob found correlated photon polarizations. This didn't happen when Victor left the photons alone.'

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