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Post by kiek on Jun 13, 2009 0:52:58 GMT 4
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Post by kiek on Jun 13, 2009 1:12:35 GMT 4
This was sent to me by a friend. Please take a moment to review and sign the petition. It's important.Breast Cancer PetitionProtect Breast Cancer Patients from "Drive-Through" MastectomiesLifeTime TVwww.mylifetime.com/my-lifetime-commitment/breast-cancer/petition/breast-cancer-petitionThe Bipartisan Breast Cancer Patient Protection Act Needs Your Support! Representatives Rosa DeLauro (D-Connecticut) and Joe Barton (R-Texas) and Senators Mary Landrieu (D-Louisiana) and Olympia Snowe (R-Maine) recently re-introduced the bipartisan Breast Cancer Patient Protection Act in Congress. Thanks to its viewers, Lifetime has so far collected more than 23 million online petition signatures urging Congress to pass this critical legislation, which would end the practice of so-called "drive-through" mastectomies when women are forced out of the hospital only hours after invasive breast cancer surgery. Help restore patient and consumer rights to breast cancer patients and their families: - Sign Lifetime's growing petition. Lifetime will continue to deliver the signatures to Congress and make your voice heard.
- Share your story. If you or someone you love has experienced a drive-through mastectomy, we want to know. Tell us in the official Breast Cancer Survivor community discussion.
- Call or write your members of Congress and ask them to support the Breast Cancer Patient Protection Act. You may reach your member of Congress by calling the U.S. House of Representatives switchboard at 202-225-3121. To find your representative in Congress, go to: www.house.gov/house/MemberWWW.shtml.
(The information you provide here is intended for this petition only. We will pass the information along to Congress. Lifetime will not use the information for any commercial or other purpose. However, Lifetime cannot be responsible for the use of this information by Congress.)[Note: The "Congress" isn't even responsible for themselves. It's a given that they wouldn't claim "responsibility" for any "data" or "information" and/or its use.] Cannot sign either, but I would have if I could! This is outragous!  But more and more we will see this happening, here in NL as well, because the healthcarecosts are skyrocketing ('goobers' filling their pockets)! It's too expensive to keep you there, the bed must be used for yet another 'victim'! Grrrr...makes me very angry and sad  |
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Post by avid on Jun 13, 2009 1:36:45 GMT 4
Absolutely real - but if one looks into scalar cloud distortions this is indicative of unnatural weather manipulations. Avid x |
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Post by chaliceman on Jun 13, 2009 1:43:07 GMT 4
What the heck is Fulford talking with Zagami for? Zagami was compromised last year so badly that Project Camelot had to publicly disavow any further contact or association with him. Seems he went over the deep end with paranoid rants about unrealistic claims he could influence events, enlisting his private militia to effect change, and much more. Has he been taking magical pills to get better?
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Post by avid on Jun 13, 2009 3:53:34 GMT 4
What the heck is Fulford talking with Zagami for? Zagami was compromised last year so badly that Project Camelot had to publicly disavow any further contact or association with him. Seems he went over the deep end with paranoid rants about unrealistic claims he could influence events, enlisting his private militia to effect change, and much more. Has he been taking magical pills to get better? I must admit that I felt uneasy about his appearance on these videos, as the last 'live skype-talk' with Bill and Kerry was quite disturbing. He was under some 'influence' and his language was quite insulting. He had supposedly turned his back on the 'Illuminati' to tell all, now he's representing them.... Something isn't balancing out. Pinch of salt then...?  |
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Post by nodstar on Jun 13, 2009 5:05:54 GMT 4
Sally Anne ..
Please stand by for PM .. ;D
Love
Nod
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Post by nodstar on Jun 13, 2009 5:12:26 GMT 4
FORUM NOTICE
ALL NEW REGISTRATIONS HAVE BEEN TEMPORARILY SUSPENDED
PENDING FORUM REVAMP AND NEW RULES FOR MEMBERSHIP
MEMBERS WHO HAVE JOINED AND NOT POSTED WITH THE EXCEPTION
OF EDO MEMBERS HAVE BEEN DELETED
IF YOU ARE ONE OF THOSE PEOPLE YOU WILL HAVE A CHANCE TO REAPPLY
FOR MEMBERSHIP IN THE VERY NEAR FUTURE
SUBJECT TO THE THE APPROVAL OF THE MEMBERSHIP COMMITTEE
THERE WILL BE BIG CHANGES COMING TO THIS FORUM ;D
BEST WISHES TO YOU ALL 
POST SCRIPT ..
THOSE WHO HAVE JOINED IN THE LAST 24 HOURS WILL HAVE TO REAPPLY
TO THE MEMBERSHIP COMMITTEE
THE ADDRESS WILL BE POSTED FOR APPLICATIONS [/size][/b] Nodstar* admin and mod
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Post by avid on Jun 13, 2009 23:30:06 GMT 4
A small divergence here - today was full of sunshine, so we did the giant hedges (now that small birdies hatched and no nests left occupied)! 20 wood pidgeons awaited their 'organic seeds' at 4.00pm (they 'know' the time!!!). I've raked up all detritus from under hedges so little birdies can find their way again, hanging birdy feeders stuffed with baby birdies (10 in one 'squirrel-proof' cage ;D ;D) Life is so much fun in my garden - apart from puddy cats pointing desperately into mouth (get in here) to no avail ;D ;D Puddy cats stuffed with luxury fud so really not that hungry - especially as we don't have doggy visitors (at the mo)' We had a BBQ tonight, and await rain in the morning.... Isn't life normal in nature... Aye-up P u s s y c a t s were turned into girl thingies - so changed them to puddy cats! ;D ;D Love Avid x |
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Post by towhom on Jun 14, 2009 3:33:11 GMT 4
Greenland Ice Sheet Melting Faster Than Expected; Larger Contributor To Sea-level Rise Than ThoughtScienceDaily
June 13, 2009www.sciencedaily.com/releases/2009/06/090612092741.htmThe Greenland ice sheet is melting faster than expected, according to a new study led by a University of Alaska Fairbanks researcher and published in the journal Hydrological Processes. Study results indicate that the ice sheet may be responsible for nearly 25 percent of global sea rise in the past 13 years. The study also shows that seas now are rising by more than 3 millimeters a year--more than 50 percent faster than the average for the 20th century.UAF researcher Sebastian H. Mernild and colleagues from the United States, United Kingdom and Denmark discovered that from 1995 to 2007, overall precipitation on the ice sheet decreased while surface ablation--the combination of evaporation, melting and calving of the ice sheet--increased. According to Mernild’s new data, since 1995 the ice sheet lost an average of 265 cubic kilometers per year, which has contributed to about 0.7 millimeters per year in global sea level rise. These figures do not include thermal expansion--the expansion of the ice volume in response to heat--so the contribution could be up to twice that.The Greenland ice sheet has been of considerable interest to researchers over the last few years as one of the major indicators of climate change. In late 2000/early 2001 and in 2007, major glacier calving events sent up to 44 square miles of ice into the sea at a time. Researchers are studying these major events as well as the less dramatic ongoing melting of the ice sheet through runoff and surface processes. Ice melt from a warming Arctic has two major effects on the ocean. First, increased water contributes to global sea-level rise, which in turn affects coastlines across the globe. Second, fresh water from melting ice changes the salinity of the world’s oceans, which can affect ocean ecosystems and deep water mixing.“Increasing sea level rise will be a problem in the future for people living in coastal regions around the globe,” said Mernild. “Even a small sea level rise can be a problem for these communities. It is our hope that this research can provide people with accurate information needed to plan for protecting people and communities.” Journal reference:
Sebastian H. Mernild, Glen E. Liston, Christopher A. Hiemstra, Konrad Steffen, Edward Hanna, Jens H. Christensen. Greenland Ice Sheet surface mass-balance modelling and freshwater flux for 2007, and in a 1995-2007 perspective. Hydrological Processes, 2009; n/a DOI: 10.1002/hyp.7354
Adapted from materials provided by University of Alaska Fairbanks.
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Post by towhom on Jun 14, 2009 3:56:02 GMT 4
Life May Extend Planet's 'Life': Billion-year Life Extension For Earth Also Doubles Odds Of Finding Life On Other PlanetsScienceDaily
June 13, 2009www.sciencedaily.com/releases/2009/06/090612203303.htmRoughly a billion years from now, the ever-increasing radiation from the sun will have heated Earth into inhabitability; the carbon dioxide in the atmosphere that serves as food for plant life will disappear, pulled out by the weathering of rocks; the oceans will evaporate; and all living things will disappear. Or maybe not quite so soon, say researchers from the California Institute of Technology (Caltech), who have come up with a mechanism that doubles the future lifespan of the biosphere—while also increasing the chance that advanced life will be found elsewhere in the universe. A paper describing their hypothesis was published June 1 in the early online edition of the Proceedings of the National Academy of Sciences (PNAS). Earth maintains its surface temperatures through the greenhouse effect. Although the planet's greenhouse gases—chiefly water vapor, carbon dioxide, and methane—have become the villain in global warming scenarios, they're crucial for a habitable world, because they act as an insulating blanket in the atmosphere that absorbs and radiates thermal radiation, keeping the surface comfortably warm. As the sun has matured over the past 4.5 billion years, it has become both brighter and hotter, increasing the amount of solar radiation received by Earth, along with surface temperatures. Earth has coped by reducing the amount of carbon dioxide in the atmosphere, thus reducing the warming effect. (Despite current concerns about rising carbon dioxide levels triggering detrimental climate change, the pressure of carbon dioxide in the atmosphere has dropped some 2,000-fold over the past 3.5 billion years; modern, man-made increases in atmospheric carbon dioxide offset a fraction of this overall decrease.) The problem, says Joseph L. Kirschvink, the Nico and Marilyn Van Wingen Professor of Geobiology at Caltech and a coauthor of the PNAS paper, is that "we're nearing the point where there's not enough carbon dioxide left to regulate temperatures following the same procedures." Kirschvink and his collaborators Yuk L. Yung, a Caltech professor of planetary science, and graduate students King-Fai Li and Kaveh Pahlevan, say that the solution is to reduce substantially the total pressure of the atmosphere itself, by removing massive amounts of molecular nitrogen, the largely nonreactive gas that makes up about 78 percent of the atmosphere. This would regulate the surface temperatures and allow carbon dioxide to remain in the atmosphere, to support life, and could tack an additional 1.3 billion years onto Earth's expected lifespan. In the "blanket" analogy for greenhouse gases, carbon dioxide would be represented by the cotton fibers making up the blanket. "The cotton weave may have holes, which allow heat to leak out," explains Li, the lead author of the paper. "The size of the holes is controlled by pressure," Yung says. "Squeeze the blanket," by increasing the atmospheric pressure, "and the holes become smaller, so less heat can escape. With less pressure, the holes become larger, and more heat can escape," he says, helping the planet to shed the extra heat generated by a more luminous sun. Strikingly, no external influence would be necessary to take nitrogen out of the air, the scientists say. Instead, the biosphere itself would accomplish this, because nitrogen is incorporated into the cells of organisms as they grow, and is buried with them when they die. In fact, "This reduction of nitrogen is something that may already be happening," says Pahlevan, and that has occurred over the course of Earth's history. This suggests that Earth's atmospheric pressure may be lower now than it was earlier in the planet's history. Proof of this hypothesis may come from other research groups that are examining the gas bubbles formed in ancient lavas to determine past atmospheric pressure: the maximum size of a forming bubble is constrained by the amount of atmospheric pressure, with higher pressures producing smaller bubbles, and vice versa. If true, the mechanism also would potentially occur on any extrasolar planet with an atmosphere and a biosphere. "Hopefully, in the future we will not only detect Earth-like planets around other stars but learn something about their atmospheres and the ambient pressures," Pahlevan says. "And if it turns out that older planets tend to have thinner atmospheres, it would be an indication that this process has some universality." Adds Yung: "We can't wait for the experiment to occur on Earth. It would take too long. But if we study exoplanets, maybe we will see it. Maybe the experiment has already been done." Increasing the lifespan of our biosphere—from roughly 1 billion to 2.3 billion years—has intriguing implications for the search for life elsewhere in the universe. The length of the existence of advanced life is a variable in the Drake equation, astronomer Frank Drake's famous formula for estimating the number of intelligent extraterrestrial civilizations in the galaxy. Doubling the duration of Earth's biosphere effectively doubles the odds that intelligent life will be found elsewhere in the galaxy. "It didn't take very long to produce life on the planet, but it takes a very long time to develop advanced life," says Yung. On Earth, this process took four billion years. "Adding an additional billion years gives us more time to develop, and more time to encounter advanced civilizations, whose own existence might be prolonged by this mechanism. It gives us a chance to meet." Journal reference:
Li et al. Atmospheric pressure as a natural climate regulator for a terrestrial planet with a biosphere. Proceedings of the National Academy of Sciences, 2009; DOI: 10.1073/pnas.0809436106
Adapted from materials provided by California Institute of Technology, via EurekAlert!, a service of AAAS.
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Post by towhom on Jun 14, 2009 4:11:02 GMT 4
Ginkgo Reduces Neuropathic Pain In Animal StudiesScienceDaily
June 12, 2009www.sciencedaily.com/releases/2009/06/090605175332.htmAn extract of ginkgo biloba shows scientific evidence of effectiveness against one common and hard-to-treat type of pain, according to animal data reported in the June issue of Anesthesia & Analgesia, official journal of the International Anesthesia Research Society (IARS). Dr. Yee Suk Kim and colleagues of The Catholic University of Seoul, South Korea, performed experiments in rats to evaluate the effectiveness of ginkgo against neuropathic pain, a common pain problem associated with herpes zoster, limb injury, or diabetes. Affected patients may feel severe pain in response to harmless stimuli like heat, cold, or touch. Objective Evidence of Pain Reduction with GinkgoIn the experiments, rats with neuropathic pain were treated with different doses of a standardized ginkgo biloba extract or with an inactive solution. Objective tests were performed to see how ginkgo affected neuropathic pain responses to cold and pressure. For both cold and pressure stimuli, pain responses were significantly reduced in ginkgo-treated rats. This was so on before-and-after treatment comparisons and on comparison of ginkgo-treated versus placebo-treated animals. The higher the dose of ginkgo extract, the greater the pain-relieving effect. Pain was reduced for at least two hours after ginkgo treatment. The study provides no evidence as to how ginkgo works to reduce pain. Several mechanisms are possible, including antioxidant activity, an anti-inflammatory effect, or protection against nerve injury—perhaps in combination. Many herbs and "alternative" drugs are commonly used without prescriptions for a wide range of purposes, despite a lack of scientific evidence for health claims. Ginkgo, one of the most popular herbal products, is widely used as a memory enhancer, among other purposes. The new study provides the first scientific evidence that ginkgo has a real effect in reducing neuropathic pain. New treatments are needed for neuropathic pain, which does not always respond well to available treatments. "It's still too early to stock up on ginkgo biloba if you have chronic pain," comments Dr. Steven L. Shafer of Columbia University, Editor-in-Chief of Anesthesia & Analgesia. Many treatments that are effective in animals do not prove to be effective in humans, or prove to have unacceptable toxic effects when given to patients, Dr. Shafer reminds. "However," he adds, "it is at least reassuring to know that scientists are investigating the properties of this ancient oriental herbal medication in an effort to determine what chemical constituents account for the many beneficial effects traditionally ascribed to it."Adapted from materials provided by International Anesthesia Research Society (IARS), via Newswise.
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Post by towhom on Jun 14, 2009 4:36:22 GMT 4
Lab-on-a-Chip
Brain-on-a-Chip
Now we have....Manipulating Light On A Chip For Quantum TechnologiesScienceDaily
June 10, 2009www.sciencedaily.com/releases/2009/06/090608095042.htmA team of physicists and engineers at Bristol University has demonstrated exquisite control of single particles of light — photons — on a silicon chip to make a major advance towards long-sought-after quantum technologies, including super-powerful quantum computers and ultra-precise measurements.The Bristol Centre for Quantum Photonics has demonstrated precise control of four photons using a microscopic metal electrode lithographically patterned onto a silicon chip. The photons propagate in silica waveguides — much like in optical fibres — patterned on a silicon chip, and are manipulated with the electrode, resulting in a high-performance miniaturized device. “We have been able to generate and manipulate entangled states of photons on a silicon chip” said PhD student, Jonathan Matthews, who together with Alberto Politi performed the experiments. “These entangled states are responsible for famously ‘weird’ behaviour arising in quantum mechanics, but are also at the heart of powerful quantum technologies.”“This precise manipulation is a very exciting development for fundamental science as well as for future quantum technologies.” said Prof Jeremy O’Brien, Director of the Centre for Quantum Photonics, who led the research. The team reports its results in the June issue of Nature Photonics, a sister journal of the science journal Nature, and in a Postdeadline Paper at 'The International Quantum Electronics Conference (IQEC)' on June 4 in Baltimore, USA [IQEC Postdeadline Papers]. Quantum technologies with photonsQuantum technologies aim to exploit the unique properties of quantum mechanics, the physics theory that explains how the world works at microscopic scales. For example a quantum computer relies on the fact that quantum particles, such as photons, can exist in a “superposition” of two states at the same time — in stark contrast to the transistors in a PC which can only be in the state “0” or “1”.Photons are an excellent choice for quantum technologies because they are relatively noise-free; information can be moved around at the speed of light; and manipulating single photons is easy. Making two photons “talk” to each other to generate the all-important entangled states is much harder, but Professor O’Brien and his colleagues at the University of Queensland demonstrated this in a quantum logic gate back in 2003 [Nature 426, 264 (2003)]. Last year, the Centre for Quantum Photonics at Bristol showed how such interactions between photons could be realised on a silicon chip, pointing the way to advanced quantum technologies based on photons [Science 320, 646 (2008)]. Photons are also required to “talk” to each other to realise the ultra-precise measurements that harness the laws of quantum mechanics. In 2007 Professor O’Brien and his Japanese collaborators reported such a quantum metrology measurement with four photons [Science 316, 726 (2007)]. Manipulating photons on a silicon chip“Despite these impressive advances, the ability to manipulate photons on a chip has been missing,” said Mr Politi. “For the last several years the Centre for Quantum Photonics has been working towards building fully functional quantum circuits on a chip to solve these problems,” added Prof O’Brien. The team coupled photons into and out of the chip, fabricated at CIP Technologies, using optical fibres. Application of a voltage across the metal electrode changed the temperature of the silica waveguide directly beneath it, thereby changing the path that the photons travelled. By measuring the output of the device they confirmed high-performance manipulation of photons in the chip. The researchers proved that one of the strangest phenomena of the quantum world, namely “quantum entanglement”, was achieved on-chip with up to four photons. Quantum entanglement of two particles means that the state of either of the particles is not defined, but only their collective state, and results in an instantaneous linking of the particles.This on-chip entanglement has important applications in quantum metrology and the team demonstrated an ultra-precise measurement in this way. “As well as quantum computing and quantum metrology, on-chip photonic quantum circuits could have important applications in quantum communication, since they can be easily integrated with optical fibres to send photons between remote locations,” said Alberto Politi. “The really exciting thing about this result is that it will enable the development of reconfigurable and adaptive quantum circuits for photons. This opens up all kinds of possibilities,” said Prof O’Brien. A commentary on the work that appeared in the same issue [Nature Photonics 3, 317 (2009)] described it as “an important step in the quest for quantum computation” and concluded: “The most exciting thing about this work is its potential for scalability. The small size of the [device] means that far greater complexity is possible than with large-scale optics.” The other co-author of the Nature Photonics paper is Dr André Stefanov, formerly a Research fellow in the Centre for Quantum Photonics, and now at the Federal Office of Metrology METAS, Switzerland. The work was funded by the Engineering and Physical Sciences Research Council (EPSRC), the Quantum Information Processing Interdisciplinary Research Collaboration (QIP IRC), the US government Intelligence Advanced Research Projects Activity (IARPA) and the Leverhulme Trust.
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Post by towhom on Jun 14, 2009 4:42:55 GMT 4
Human Exposure To Controversial Chemical BPA May Be Greater Than Dose Considered SafeScienceDaily
June 11, 2009www.sciencedaily.com/releases/2009/06/090610124618.htmPeople are likely being exposed to the commonly used chemical bisphenol A (BPA) at levels much higher than the recommended safe daily dose, according to a new study in monkeys. The results will be presented Thursday at The Endocrine Society's 91st Annual Meeting in Washington, D.C. "BPA is now known to be a potent estrogen," said Frederick vom Saal, PhD, a co-author of the new study and a professor of biological sciences at the University of Missouri-Columbia. "Human and animal studies indicate it could be related to diabetes, heart disease, liver abnormalities, miscarriage and other reproductive abnormalities, as well as prostate and breast cancer."The U.S. Food and Drug Administration (FDA) declared BPA is safe based on estimates that people consume only small amounts each day from food. However, recent research indicated that U.S. adults are exposed to more BPA from multiple sources than previously thought, vom Saal said. BPA is found in polycarbonate plastic food and beverage containers, such as water and infant bottles, as well as in the epoxy resin lining of cans and other sources. The chemical can leach into food and beverages, according to the National Institutes of Health, which funded the study by vom Saal and colleagues. "Between 8 and 9 billion pounds of BPA are used in products every year," vom Saal said. In their study, he and his colleagues fed five female adult monkeys an oral dose of BPA (400 micrograms per kilogram of body weight). This amount is more than 400 times higher than the amount that the U.S. Food and Drug Administration (FDA) estimates that human adults are exposed to and 8 times higher than the estimated safe daily amount to consume, according to vom Saal.
Yet the blood levels of biologically active BPA over the next 24 hours were lower in the monkeys than the average levels found in people in the United States and other developed countries, vom Saal said. For levels to be higher in people when measured, their exposure dose must be greater than that given to the monkeys, he explained.
"These results suggest that the average person is likely exposed to a daily dose of BPA that far exceeds the current estimated safe daily intake dose," vom Saal said.He said that BPA exposure must come from many unknown sources, in addition to food and beverage containers. Like drugs, BPA acts in pulses, with each exposure creating a high-level pulse before it is cleared in the urine, according to vom Saal. The researchers are continuing the study in more monkeys, but vom Saal said they do not expect to get different findings because the data in the first five animals were "very consistent." The species of monkey that they used (rhesus) metabolizes BPA similar to humans, he added. Adapted from materials provided by The Endocrine Society, via EurekAlert!, a service of AAAS.
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Post by towhom on Jun 14, 2009 4:51:35 GMT 4
'Junk' DNA Proves To Be Highly ValuableScienceDaily
June 12, 2009www.sciencedaily.com/releases/2009/06/090606105203.htmWhat was once thought of as DNA with zero value in plants--dubbed "junk" DNA--may turn out to be key in helping scientists improve the control of gene expression in transgenic crops. That's according to Agricultural Research Service (ARS) plant pathologist Bret Cooper at the agency's Soybean Genomics and Improvement Laboratory in Beltsville, Md., and collaborators at Johns Hopkins University in Baltimore, Md. For more than 30 years, scientists have been perplexed by the workings of intergenic DNA, which is located between genes. Scientists have since found that, among other functions, some intergenic DNA plays a physical role in protecting and linking chromosomes. But after subtracting intergenic DNA, there was still leftover or "junk" DNA which seemed to have no purpose. Cooper and collaborators investigated "junk" DNA in the model plant Arabidopsis thaliana, using a computer program to find short segments of DNA that appeared as molecular patterns. When comparing these patterns to genes, Cooper's team found that 50 percent of the genes had the exact same sequences as the molecular patterns. This discovery showed a sequence pattern link between "junk" and coding DNA. These linked patterns are called pyknons, which Cooper and his team believe might be evidence of something important that drives genome expansion in plants. The researchers found that pyknons are also the same in sequence and size as small segments of RNA that regulate gene expression through a method known as gene silencing. This evidence suggests that these RNA segments are converted back into DNA and are integrated into the intergenic space. Over time, these sequences repeatedly accumulate. Prior to this discovery, pyknons were only known to exist in the human genome. Thus, this discovery in plants illustrates that the link between coding DNA and junk DNA crosses higher orders of biology and suggests a universal genetic mechanism at play that is not yet fully understood.The data suggest that scientists might be able to use this information to determine which genes are regulated by gene silencing, and that there may be some application for the improvement of transgenic plants by using the pyknon information. This research was published online as an advance article on the Molecular BioSystems website, and will be published later this year in a special issue of Computational Systems Biology. Journal reference:
Feng et al. Coding DNA repeated throughout intergenic regions of the Arabidopsis thaliana genome: evolutionary footprints of RNA silencing. Molecular BioSystems, 2009; DOI: 10.1039/b903031j
Adapted from materials provided by USDA/Agricultural Research Service.
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Post by towhom on Jun 14, 2009 5:10:51 GMT 4
Isn't this wonderful...  Targeting the Brain with Sound WavesUltrasound might provide a new, noninvasive way to control brain activityTechnology Review
Thursday, June 04, 2009www.technologyreview.com/biomedicine/22746/Ultrasound waves, currently used in medicine for prenatal scans and other diagnostic purposes, could one day be used as a noninvasive way to control brain activity. Over the past two years, scientists have begun experimenting with low-frequency, low-intensity ultrasound that can penetrate the skull and activate or silence brain cells. Researchers hope that the technology could provide an alternative to more-invasive techniques, such as deep-brain stimulation (DBS) and vagus nerve stimulation, which are used to treat a growing number of neurological disorders. "Once people have found out what they can do with DBS and vagus nerve stimulation, we think we can unplug those devices and control activity from outside the body," says William (Jamie) Tyler, a neuroscientist at Arizona State University, in Tempe. Tyler has started a company called SynSonix to commercialize the technology. Devices designed to treat brain disorders have grown in popularity in recent years. DBS, which is used to treat Parkinson's disease, dystonia, and obsessive-compulsive disorder, delivers an electrical jolt to the brain via an implanted electrode. Because of its invasive nature, however, DBS is only used for severe cases that are untreatable with medication. A less invasive technique is transcranial magnetic stimulation (TMS), in which an electric coil placed over the head generates a magnetic field that passes through the skull and excites neurons in the brain below. TMS is used to treat clinical depression, but it can only target the more superficial parts of the brain. "With ultrasound, we have a much better spatial focus than [with] DBS," says Tyler. "And unlike TMS, we can get anywhere in the brain." Ultrasound--consisting of sound waves with a frequency above 20 kilohertz--has been used for decades in medicine to image muscle, organs, and fetuses. In the past five years, better tools for focusing ultrasound energy have enabled its use as an ablation tool: surgeons can now use high-intensity, high-frequency ultrasound (HIFU) to essentially burn away uterine fibroids. HIFU is also in clinical testing for treating brain tumors, breast tumors, and prostate cancer.These same tools are now allowing scientists to apply ultrasound to control the brain, an idea that has actually been around for decades. Better ultrasound transducers, which generate the acoustic waves, enable more-precise focusing of ultrasound energy. And magnetic resonance imaging (MRI) used in conjunction with ultrasound allows surgeons to target specific areas of the body more precisely. "The ability to marry focused ultrasound with MR [magnetic resonance] guidance is exceedingly powerful," says Neal Kassell, a neurosurgeon at the University of Virginia, in Charlottesville, and chairman of the Focused Ultrasound Surgery Foundation, a nonprofit based in Charlottesville that was founded to develop new applications for focused ultrasound. One of the challenges in using ultrasound to target the brain is figuring out how to get the sound waves through the skull in a controlled manner. Typically, ultrasound operates in the megahertz to gigahertz range--frequencies that are fine for passing through soft tissue but would liquefy bone. (As bone absorbs the energy of the acoustic wave, it heats up.) Researchers at Brigham and Women's Hospital, in Boston, have found that an ultrasound frequency of less than one megahertz can do the trick, but with a trade-off: the lower the frequency, the more difficult it is to focus the energy on a particular point in the brain. In the past year, however, scientists have had some success in solving this trade-off. Detailed images of the skull generated via CT scan and MRI can help scientists calculate the best way to focus the sound waves, says Seung-Schik Yoo, a neuroscientist at Brigham and Women's and Harvard Medical School. In as yet unpublished work, Yoo and his colleagues have demonstrated that low-frequency, low-intensity ultrasound can successfully suppress visual activity in rabbits' brains, as well as selectively trigger activity in the motor cortex. "We are also looking at the ability to modulate hormones or neurotransmitters, which may have application for psychiatric disorders, obesity, and addiction," says Yoo. In a paper published last year in the journal PLoS ONE, Tyler demonstrated that low-frequency, low-intensity ultrasound can activate channels that sit in the membrane of nerve cells in a slice of brain tissue, triggering the cells to send an electrical message through the neural circuit. He has since been able to use ultrasound to stimulate the motor cortex and trigger movement in live mice. This work has not yet been published.Researchers hope to co-opt instruments developed for HIFU for this new application. Several instrument companies have developed phased arrays of ultrasound transducers, which allow precise targeting of ultrasound energy, and which are currently being tested for removal of brain tumors. "Depending on individual anatomy of the skull, you can program the ultrasound equipment to fire individual elements to deliver a well-characterized beam, in terms of location and size, that can be tailor-made to each patient," says Yoo. Because focused ultrasound is already used extensively, researchers are optimistic that it will not face any major hurdles in moving toward clinical testing. "For neurologists and neurosurgeons, it's a well-established technique," says Tyler. "The safety margins are well known." Adds Kassell, "I think it will actually be easier to get approval [than it was for HIFU] because the pressure of the focused ultrasound is less pressure than the brain gets from transcranial Doppler, a diagnostic device used to look at vessels in the head after stroke and hemorrhage." Kassell says that the foundation is most interested in using low-intensity, low-frequency ultrasound for surgical planning. In epilepsy patients, surgeons could use the technology to temporarily silence a piece of brain tissue thought to be responsible for triggering seizures, thus confirming the correct localization, and then use HIFU to ablate that piece of tissue. Tyler is most interested in using focused ultrasound for treating Parkinson's disease. "Since it's not invasive, we might be able to treat patients much earlier in progression," he says. "Right now, people who get DBS are the worst-case patients." While initial devices would likely resemble a smaller version of MRI machines, treating Parkinson's patients would require a wearable or implantable device capable of delivering continual stimulation. Tyler's team is working on flexible ultrasound transducers that could be implanted on top of the skull or formulated into a cap. It's not yet clear how ultrasound triggers electrical activity in neurons, but some believe that it is through thermal energy generated by sound waves. Tyler, however, says he has evidence that the neurons are activated through mechanical energy. Previous research has indeed shown that the neuron channels that control electrical activity in the brain can be activated with mechanical pressure. "What we think is happening is some kind of microcavitational effect, such as radiation or sheer strain, which affect the channels that control neural activity," he says.
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