— An increasing number of 70 year olds are having good sex and more often, and women in this age group are particularly satisfied with their sex lives, according to a study published on the British Medical Journal website.
Knowledge about sexual behaviour in older people (70 year olds) is limited and mainly focuses on sexual problems, less is known about "normal" sexual behaviour in this age group.
Nils Beckman and colleagues from the University of Gothenburg in Sweden, studied attitudes to sex in later life among four representative population samples of 70 year olds in Sweden, who they interviewed in 1971-2, 1976-7, 1992-3, and 2000-1. In total, over 1 500 people aged 70 years were interviewed about different aspects of their sex lives including sexual dysfunctions, marital satisfaction and sexual activity.
The authors found that over the thirty year period the number of 70 year olds of both sexes reporting sexual intercourse increased: married men from 52% to 68%, married women from 38% to 56%, unmarried men from 30% to 54%, and unmarried women from 0.8% to 12%.
In addition, the number of women reporting high sexual satisfaction increased, more women reported having an orgasm during sex and fewer reported never having had an orgasm.
While the proportion of women reporting low satisfaction with their sex lives decreased, the proportion of men reporting low satisfaction increased. The authors suggest that this might be because it is now more acceptable for men to admit "failure" in sexual matters.
They also note that the number of men reporting erectile dysfunction deceased, whereas the proportion reporting ejaculation dysfunction increased, but the proportion reporting premature ejaculation did not change.
Interestingly, both men and women blame men when sexual intercourse stops between them. This finding replicates the results of other studies in the 1950s and 2005-06.
"Our study...shows that most elderly people consider sexual activity and associated feelings a natural part of later life", they conclude.
These findings emphasise the important and positive part sex plays in the lives of 70 year olds and is a welcome contribution to the limited literature about sexual behaviour in older people, writes Professor Peggy Kleinplatz from the University of Ottawa in Canada.
It will hopefully highlight the need for doctors to be trained to ask all patients, regardless of age, about their sexual concerns, she adds.
Showing posts with label Science/Innovations. Show all posts
Showing posts with label Science/Innovations. Show all posts
Saturday, July 12, 2008
Wednesday, July 9, 2008
Live Longer: The One Anti-Aging Trick That Works
While the quest for the proverbial Fountain of Youth is endless and typically fruitless, one method known to extend the human lifespan by up to five years has quietly become accepted among leading researchers.
The formula is simple: Eat less. It could add years to your life, several experts now say. And done in moderation, it could at least help you live a more healthy life.
The only question is: Will the average person do it?
While little short of a nip-and-tuck will make you look younger, calorie restriction, as it is called, is as close to a real Fountain of Youth as any known technique comes. Even scientists who are cautious about anti-aging hype say it works, both by cutting risks for some diseases and by allowing all body cells, somehow, to hang in there longer.
"There is plenty of evidence that calorie restriction can reduce your risks for many common diseases including cancer, diabetes and heart disease," says Saint Louis University researcher Edward Weiss, who last week announced a new study that brings fresh understanding to how it works. "And you may live to be substantially older."
The numbers
Here's a rough rule of thumb that many experts generally agree on now: Eat 15 percent less starting at age 25 and you might add 4.5 years to your life, says Eric Ravussin, who studies human health and performance at the Pennington Biomedical Research Center in Louisiana.
One important caveat: Ravussin's estimate is based mostly on studies of other animals and only preliminary research in humans. But the work by Weiss and others is unlocking the mysteries of aging and suggesting the animal studies apply to humans.
"There is absolutely no reason to think it won't work," Ravussin told LiveScience.
Perhaps even more promising, though in early stages of research, are drugs designed on the basis of what's been learned from calorie-restriction studies. Those drugs would target human cells to deliver the same benefits, turning off bad things and turning on good things to extend cell life in general, or offer new therapies and cures to vexing diseases like Alzheimer's and cancer.
If you can hang in there until these promising new drug therapies are developed, you may live in a world where lifespan increases by 10 to 15 years, researchers say.
Don't plan on living to be 200, Ravussin said, "but I think we're going to gain quite a few years."
Mysteries remain
Scientists aren't sure exactly why calorie restriction slows aging. But they're on the verge of a firm understanding. In a nutshell, it is thought to lower metabolic rate and cause the body to generate fewer damaging "free radicals."
One hypothesis is that it decreases a thyroid hormone, triiodothyronine (T3), which then slows metabolism and tissue aging.
Weiss and colleagues studied men and women, aged 50 to 60, who did not smoke, were not obese and were in good health. The volunteers were split into three groups - a calorie-restriction group, an exercise group, or a control group - and followed for one year. The calorie-restriction group cut back by 300 to 500 calories per day. (A typical healthy adult diet should include about 2,000 calories.) Volunteers in the exercise group maintained their regular diet and exercised regularly.
While both the calorie-restriction and exercise groups experienced similar changes of body fat mass, only those in the calorie restriction group also experienced lower levels of the thyroid hormone. A longer-term study is still needed to pin down whether reducing T3 levels through calorie restriction indeed slows the aging process as suspected, the scientists say.
The results were published in the June issue of the journal Rejuvenation Research.
Step-by-step
Weiss' work advances the body of anti-aging knowledge, said Christy Carter, an aging researcher and assistant professor at the University of Florida College of Medicine.
"The more that scientists can demonstrate similar biological profiles between rodents and humans with regards to calorie restriction, the greater the possibility that lifespan extension will translate to human as well," Carter said.
Weiss figured it's sensible to take steps now. You can cut 300 to 500 calories by simply skipping dessert or substituting a turkey sandwich for fast food. A nutritional diet and exercise are important to any weight-loss effort, Weiss and others caution.
"Our research provides evidence that calorie restriction does work in humans like it has been shown to work in animals," Weiss said. "The next step is to determine if this in fact slows age-related tissue deterioration. The only way to be certain, though, is to do a long-term study."
Others agree: more research is needed.
"I think that they've documented a real and interesting effect of caloric restriction in humans," said UCLA evolutionary biologist Jay Phelan. "But they are still a long way from demonstrating that it changes human lifespan at all."
Proven in animals
Evidence that calorie restriction boosts lifespans in rodents is solid. Christiaan Leeuwenburgh of the University of Florida's Institute on Aging showed in 2006 that eating just 8 percent less and exercising a little more over a lifespan can reduce or even reverse aging-related cell and organ damage in rats.
Various studies have shown that cutting calories by 20 to 40 percent significantly both extends life and, with a little exercise, leaves old animals in better shape.
Eating fewer calories also reduces age-related chronic diseases such as cancers, heart disease, and stroke in rodents. That's important because it suggests ways to not just make us live longer, but to allow us to age more gracefully, healthwise.
Research last year found that rats on a restricted diet are more physically fit in old age, apparently slowing the typical onset of physical disability. The rodents also looked and probably felt better: "Rats that ate a normal diet lost a significant amount of lean muscle mass and acquired more fat, while calorie-restricted rats maintained lean muscle mass as they aged," said lead researcher Tongjian You from the University of Buffalo. The finding was published in the October issue of the Journals of Gerontology Series A: Biological Sciences and Medical Sciences.
Rodents are thought to be good analogues to humans. Dogs are even better.
A 14-year study of 48 Labrador Retrievers found restricting their diets by 25 percent starting at 8 weeks of age extended their lives by an average of 1.8 years. For a creature that typically never gets beyond its early teens, that's a big number. The findings were published back in 2002 in the Journal of the American Veterinary Medical Association.
"The study also showed that lean body conformation forestalls some chronic illnesses, most notably osteoarthritis," said University of Pennsylvania researcher Gail K. Smith, who worked on the dog study. Ailments typically struck the lean dogs 2.1 years later than the others.
Probably works in humans
Convincing humans to eat less, and then studying the effects over a lifetime, is considerably more challenging. But mounting research suggests that what works for rats and dogs seems to apply to people.
Studies are under way with monkeys, which have lifespans of around 25 to 30 years, and early indications are promising, Ravussin said.
A study of humans last year found that cutting calories in human test subjects reduced oxidative damage in muscle cells. In the journal PLoS Medicine, the researchers speculated that the effect might translate into longer life.
Researchers caution, however, that longer lifespans does not mean immortality. The vast majority of mainstream researchers envision lifespans extending a few years.
"My estimate would be that 40 years of caloric restriction would give a 3 to 7 percent increase in longevity, so an optimistic estimate would be an additional four years or so," said Phelan, the UCLA researcher.
But researchers are quick to point out that human nature is not conducive to life-long calorie-restriction diets. "It's going to be limited to a few people who are going to try to do that," Ravussin said.
Seeking balance
"Suffering years of misery to remain super-skinny is not going to have a big payoff in terms of a longer life," Phelan said back in 2005 when the idea of "living forever" was particularly hyped in the media. "I once heard someone say caloric restriction may not make you live forever, but it sure would seem like it. Try to maintain a healthy body weight, but don't deprive yourself of all pleasure. Moderation appears to be a more sensible solution."
Phelan uses rodents as an example of why caution is warranted:
Mice will live longer if their diet is restricted by 10 percent, he said in 2005. "If you restrict their intake by 20 percent, they live even longer, and restrict them to 50 percent, they live longer still. But restrict their intake by 60 percent and they starve to death."
In an email interview the other day, Phelan said he stands by this assessment.
And Phelan now thinks there is "nothing" on the research horizon "that would extend lifespan in a significant amount, on the order of 10 or more years."
Big promise?
Other experts are optimistic that research into calorie restriction will lead to greater things.
Scientists are investigating what they call CR mimetics, or compounds that mimic the effects of calorie restriction. "This includes naturally occurring compounds and pharmaceuticals," explained Carter, the University of Florida researcher. "One that has received much attention lately is a compound called resveratrol, found in red wine."
Researchers have long pondered the French paradox: The French eat high-fat diets but live relatively long lives. Resveratrol and other compounds in red wine are thought by many to contribute to that good life. But testing any anti-aging drug or therapy sets up another tricky paradox: Nobody wants to invest in a 70-year test, and the Food and Drug Administration won't approve a chemical's use without thorough testing. There's a potential shortcut: Researchers are testing compounds thought to thwart aging on Alzheimer's patients to see if they slow the degradation of neurons. And similar human trials will begin soon on diabetes patients.
"However, many of these studies are still in the development phase, still being tested in rodent models," Carter said. "I expect that this field will begin to explode in the next few years. Caution is still merited given the need for extensive study of these compounds as to their efficacy and long-term safety."
Eventually, Ravussin thinks the combined efforts of all these research angles could extend lifespans by 15 years later this century.
In a society where lifespan has already increased significantly in recent decades, many people are at least as concerned with aging well as they are with living long.
"Many researchers are focusing on the effects of CR on health-span as opposed lifespan," Carter said. "We know that small reductions in caloric intake, even as little as 8 percent, result in improvements in health related outcomes."
- Robert Roy Britt
LiveScience Managing Editor
LiveScience.com
The formula is simple: Eat less. It could add years to your life, several experts now say. And done in moderation, it could at least help you live a more healthy life.
The only question is: Will the average person do it?
While little short of a nip-and-tuck will make you look younger, calorie restriction, as it is called, is as close to a real Fountain of Youth as any known technique comes. Even scientists who are cautious about anti-aging hype say it works, both by cutting risks for some diseases and by allowing all body cells, somehow, to hang in there longer.
"There is plenty of evidence that calorie restriction can reduce your risks for many common diseases including cancer, diabetes and heart disease," says Saint Louis University researcher Edward Weiss, who last week announced a new study that brings fresh understanding to how it works. "And you may live to be substantially older."
The numbers
Here's a rough rule of thumb that many experts generally agree on now: Eat 15 percent less starting at age 25 and you might add 4.5 years to your life, says Eric Ravussin, who studies human health and performance at the Pennington Biomedical Research Center in Louisiana.
One important caveat: Ravussin's estimate is based mostly on studies of other animals and only preliminary research in humans. But the work by Weiss and others is unlocking the mysteries of aging and suggesting the animal studies apply to humans.
"There is absolutely no reason to think it won't work," Ravussin told LiveScience.
Perhaps even more promising, though in early stages of research, are drugs designed on the basis of what's been learned from calorie-restriction studies. Those drugs would target human cells to deliver the same benefits, turning off bad things and turning on good things to extend cell life in general, or offer new therapies and cures to vexing diseases like Alzheimer's and cancer.
If you can hang in there until these promising new drug therapies are developed, you may live in a world where lifespan increases by 10 to 15 years, researchers say.
Don't plan on living to be 200, Ravussin said, "but I think we're going to gain quite a few years."
Mysteries remain
Scientists aren't sure exactly why calorie restriction slows aging. But they're on the verge of a firm understanding. In a nutshell, it is thought to lower metabolic rate and cause the body to generate fewer damaging "free radicals."
One hypothesis is that it decreases a thyroid hormone, triiodothyronine (T3), which then slows metabolism and tissue aging.
Weiss and colleagues studied men and women, aged 50 to 60, who did not smoke, were not obese and were in good health. The volunteers were split into three groups - a calorie-restriction group, an exercise group, or a control group - and followed for one year. The calorie-restriction group cut back by 300 to 500 calories per day. (A typical healthy adult diet should include about 2,000 calories.) Volunteers in the exercise group maintained their regular diet and exercised regularly.
While both the calorie-restriction and exercise groups experienced similar changes of body fat mass, only those in the calorie restriction group also experienced lower levels of the thyroid hormone. A longer-term study is still needed to pin down whether reducing T3 levels through calorie restriction indeed slows the aging process as suspected, the scientists say.
The results were published in the June issue of the journal Rejuvenation Research.
Step-by-step
Weiss' work advances the body of anti-aging knowledge, said Christy Carter, an aging researcher and assistant professor at the University of Florida College of Medicine.
"The more that scientists can demonstrate similar biological profiles between rodents and humans with regards to calorie restriction, the greater the possibility that lifespan extension will translate to human as well," Carter said.
Weiss figured it's sensible to take steps now. You can cut 300 to 500 calories by simply skipping dessert or substituting a turkey sandwich for fast food. A nutritional diet and exercise are important to any weight-loss effort, Weiss and others caution.
"Our research provides evidence that calorie restriction does work in humans like it has been shown to work in animals," Weiss said. "The next step is to determine if this in fact slows age-related tissue deterioration. The only way to be certain, though, is to do a long-term study."
Others agree: more research is needed.
"I think that they've documented a real and interesting effect of caloric restriction in humans," said UCLA evolutionary biologist Jay Phelan. "But they are still a long way from demonstrating that it changes human lifespan at all."
Proven in animals
Evidence that calorie restriction boosts lifespans in rodents is solid. Christiaan Leeuwenburgh of the University of Florida's Institute on Aging showed in 2006 that eating just 8 percent less and exercising a little more over a lifespan can reduce or even reverse aging-related cell and organ damage in rats.
Various studies have shown that cutting calories by 20 to 40 percent significantly both extends life and, with a little exercise, leaves old animals in better shape.
Eating fewer calories also reduces age-related chronic diseases such as cancers, heart disease, and stroke in rodents. That's important because it suggests ways to not just make us live longer, but to allow us to age more gracefully, healthwise.
Research last year found that rats on a restricted diet are more physically fit in old age, apparently slowing the typical onset of physical disability. The rodents also looked and probably felt better: "Rats that ate a normal diet lost a significant amount of lean muscle mass and acquired more fat, while calorie-restricted rats maintained lean muscle mass as they aged," said lead researcher Tongjian You from the University of Buffalo. The finding was published in the October issue of the Journals of Gerontology Series A: Biological Sciences and Medical Sciences.
Rodents are thought to be good analogues to humans. Dogs are even better.
A 14-year study of 48 Labrador Retrievers found restricting their diets by 25 percent starting at 8 weeks of age extended their lives by an average of 1.8 years. For a creature that typically never gets beyond its early teens, that's a big number. The findings were published back in 2002 in the Journal of the American Veterinary Medical Association.
"The study also showed that lean body conformation forestalls some chronic illnesses, most notably osteoarthritis," said University of Pennsylvania researcher Gail K. Smith, who worked on the dog study. Ailments typically struck the lean dogs 2.1 years later than the others.
Probably works in humans
Convincing humans to eat less, and then studying the effects over a lifetime, is considerably more challenging. But mounting research suggests that what works for rats and dogs seems to apply to people.
Studies are under way with monkeys, which have lifespans of around 25 to 30 years, and early indications are promising, Ravussin said.
A study of humans last year found that cutting calories in human test subjects reduced oxidative damage in muscle cells. In the journal PLoS Medicine, the researchers speculated that the effect might translate into longer life.
Researchers caution, however, that longer lifespans does not mean immortality. The vast majority of mainstream researchers envision lifespans extending a few years.
"My estimate would be that 40 years of caloric restriction would give a 3 to 7 percent increase in longevity, so an optimistic estimate would be an additional four years or so," said Phelan, the UCLA researcher.
But researchers are quick to point out that human nature is not conducive to life-long calorie-restriction diets. "It's going to be limited to a few people who are going to try to do that," Ravussin said.
Seeking balance
"Suffering years of misery to remain super-skinny is not going to have a big payoff in terms of a longer life," Phelan said back in 2005 when the idea of "living forever" was particularly hyped in the media. "I once heard someone say caloric restriction may not make you live forever, but it sure would seem like it. Try to maintain a healthy body weight, but don't deprive yourself of all pleasure. Moderation appears to be a more sensible solution."
Phelan uses rodents as an example of why caution is warranted:
Mice will live longer if their diet is restricted by 10 percent, he said in 2005. "If you restrict their intake by 20 percent, they live even longer, and restrict them to 50 percent, they live longer still. But restrict their intake by 60 percent and they starve to death."
In an email interview the other day, Phelan said he stands by this assessment.
And Phelan now thinks there is "nothing" on the research horizon "that would extend lifespan in a significant amount, on the order of 10 or more years."
Big promise?
Other experts are optimistic that research into calorie restriction will lead to greater things.
Scientists are investigating what they call CR mimetics, or compounds that mimic the effects of calorie restriction. "This includes naturally occurring compounds and pharmaceuticals," explained Carter, the University of Florida researcher. "One that has received much attention lately is a compound called resveratrol, found in red wine."
Researchers have long pondered the French paradox: The French eat high-fat diets but live relatively long lives. Resveratrol and other compounds in red wine are thought by many to contribute to that good life. But testing any anti-aging drug or therapy sets up another tricky paradox: Nobody wants to invest in a 70-year test, and the Food and Drug Administration won't approve a chemical's use without thorough testing. There's a potential shortcut: Researchers are testing compounds thought to thwart aging on Alzheimer's patients to see if they slow the degradation of neurons. And similar human trials will begin soon on diabetes patients.
"However, many of these studies are still in the development phase, still being tested in rodent models," Carter said. "I expect that this field will begin to explode in the next few years. Caution is still merited given the need for extensive study of these compounds as to their efficacy and long-term safety."
Eventually, Ravussin thinks the combined efforts of all these research angles could extend lifespans by 15 years later this century.
In a society where lifespan has already increased significantly in recent decades, many people are at least as concerned with aging well as they are with living long.
"Many researchers are focusing on the effects of CR on health-span as opposed lifespan," Carter said. "We know that small reductions in caloric intake, even as little as 8 percent, result in improvements in health related outcomes."
- Robert Roy Britt
LiveScience Managing Editor
LiveScience.com
Tuesday, July 8, 2008
Blocking Sun Not Feasible Warming Solution, Says Study
July 7, 2008 -- A proposal to reverse climate change by placing mirrors in the sky to reflect sunlight away from Earth won't give us back the same climate we had before we started emitting so much carbon dioxide, says a new study.
Researchers at the University of Bristol in the United Kingdom applied state-of-the-art global climate models to predict the effect of using reflective sunshades to send a fraction of the sunlight that enters Earth's atmosphere back into space before it can heat things up.
They compared two futures with four times the pre-industrial level of CO2: one where nothing was done, and another where the sunlight intensity was reduced to a level that achieved the lower, pre-industrial global average temperature, despite the higher CO2 levels.
The second case simulated the use of enough sunshades to drop the average temperature to pre-industrial levels, which turned out to be a reduction in sunlight of about 4.2 percent.
"Although we managed to cancel out warming on a global average, what you end up with is some areas that warm up and some that cool down," said Dan Lunt, who led the study, published in Geophysical Research Letters.
"We found warming in the Arctic and Antarctic regions, and a cooling in the equatorial regions," Lunt said. "We got a decrease in rainfall a lot of places in the world, decreases in sea ice, and some changes in the El Nino phenomenon."
These changes resulted because the mirrors reduce sunlight more at the equators than near the poles, while CO2 has a warming effect that's more equally distributed, Lunt said.
The sunshades also do nothing to prevent changes caused by increased CO2, such as ocean acidification or changes to plant growth.
Although the sunshade approach won't bring back the same climate as reducing CO2 emissions, "it is highly successful compared to doing nothing," Lunt adds.
Lunt's team's work was not the first to try to understand the effects of sunshades using a climate model. Work by Ken Caldeira of the Carnegie Institution in Stanford, Calif., also modeled a "sunshade world," but with a less complex model that did not include complete accounting for ocean circulation and sea ice.
"The study confirms our earlier findings with a better model," Caldeira said.
Although Lunt's model suggests sunshades are better than nothing, he would rather see efforts focused elsewhere.
"My personal opinion is that we should be focusing our time and money on actually reducing emissions," he said, "rather than some manmade monstrosity in space."
"The biggest problem I have with geoengineering discussions now is that the prospect of it working will reduce efforts to mitigate the problem by reducing fossil fuel emissions," agreed climatologist Alan Robock of Rutgers University in New Brunswick, N.J.
"The solution to the climate problem is mitigation, not geoengineering," he added. "These things are not perfect and there's the potential for unintended consequences."
- Jessica Marshall, Discovery News
Tuesday, July 1, 2008
Stem cells from female genital track: Scientists
Mumbai: Kolhapur-based senior gynaecologist Dr Satish Patki and senior Scientist at National Centre for Cell Science, Pune, Dr Ramesh Bhonde on Tuesday claimed that they have successfully created heart cells from the lining of uterus. They also demonstrated stem cells isolated from fallopian tubes and ovaries, and endometrium -- the entire female genital track -- were differentiated from heart, liver, bone, kidney, fat and pancreas cells. The scientists claimed that the medical fraternity could do autologous (stem cells from the patient) transplantation and thus revolutionise the entire science of obstetrics and gynaecology. This study will bring about tremendous impact in the various disorders like pregnancy induced hypertension and cases of recurrent abortions, Patki and Bhonde told media on Tuesday at Kolhapur. Clinical trials on these multi-potent cells for all gynaecological related problems are expected to start within six months, the scientists said. Apart from its human application, the present research will be useful for studying the effects of various drugs on the cells cultured in the laboratory. Similar techniques will also be useful for increasing the population of various endangered animal species like tigers or pandas by using various fertility enhancing techniques, based on this research, Bhonde said. The differentiated heart cells, myotubules, were shown beating, which can be directly used for therapeutics, Pitke told PTI from Kolhapur. Talking about the versatile nature of the uterus Pitke an IVF (test tube baby) specialist said, the lining of the uterus (endometrium) was obtained from the uterus by a simple non-surgical technique and it showed presence of a large number of stem cells. The stem cells obtained from fallopian tubes and ovaries were documented to be mesenchymal stem cells by the presence of various markers on their surface detected by the equipment called flow cytometry. The uterus is the only organ in human beings which undergoes cycles of shedding of its entire lining called endometrium and again its rapid repair over a period of one menstrual cycle. It is observed that usually 500 such cycles of shedding and repair occur in a life of a woman. Another peculiar observation in the uterine behaviour is its extreme capacity to expand in pregnancy and later again to return to its original size after delivery. The uterus weighs only 70 grams during non-pregnant status while it weighs about 1100 grams at full term pregnancy. Similarly, the volume of the uterus increases from hardly two ml to 5000 ml from non-pregnant to full term pregnant stage respectively. Such extremes of variation in size are not possible in any other human organ, Pitke said. One more interesting finding which stimulated the research by Patki and Bhonde was the immunological versatility shown by the uterus. This is the first of its kind research in the world literature, which has been accepted for publication by US based International 'Journal of Medical hypothesis', the researchers said, adding that they had applied for patent for their original work. |
US lab develops a quicker way to catch a thief
Federal researchers say they've developed a human identification test that's faster and possibly cheaper than DNA testing. It would be a handy new weapon in the arsenal for detectives, forensic experts and the military, though no one expects it to replace DNA analysis — and its promoters say it is not intended to. The new method analyses antibodies. Each person has a unique antibody bar code that can be gleaned from blood, saliva or other bodily fluids. Antibodies are proteins used by the body to fend off viruses or perform routine physiological housekeeping. "DNA is a physical code that describes you ... and in many ways so are your antibodies," said Dr. Vicki Thompson, a chemical engineer at the Idaho National Laboratory who's been working with other researchers to perfect the test for the past 10 years. The scientists say an antibody profile can yield results faster and more cheaply and be performed in the field with minimal training. National lab administrators have licensed the technology exclusively to Identity Sciences LLC in Alpharetta, Ga. The Georgia startup plans to begin rolling out test kits and training to law enforcement, the military and forensic and medical labs around the globe by fall of 2009. Ken Haas, vice president of marketing, says the test is not intended to supplant DNA testing, the recognized gold standard in human identification. But Haas says the value of antibody profiling is as a screening tool to help make sense of a crime scene, sort out the blood trails or spatter from multiple victims or more quickly identify body parts on a battlefield or at the scene of a disaster like the Sept. 11, 2001 attacks. It may also reduce the number of DNA tests required in an investigation, potentially saving time and money and easing the growing backlog, he said. Results from tests on blood serum or dried blood can be ready in two hours, a fraction of the time it takes to run similar tests for DNA matches. However, a major drawback for now is the lack of a national antibody database. That's one of the reasons antibody testing is not likely to be used at the outset of an investigation to link suspects to crimes or establish probable cause to justify issuing an arrest warrant. Company officials say beta testing by forensic scientists at simulated crime scenes at seven locations across the country has produced positive results and reinforced the notion that an eager market awaits. The company declined to say where the testing occurred, citing nondisclosure agreements with participants. The company has not yet put a price tag on the field kits. But executives say their product will be significantly cheaper than DNA analysis, which can run anywhere from $500 to $3,000 per sample because it requires sophisticated equipment and lab time. "We don't see this yet as a product to take to court," said Gene Venesky, vice president of Identity Sciences. "But we do see this as a way to get the case moving forward toward a final, legal resolution." Still, some forensics experts say that kind of scrutiny may be unavoidable, especially if the test takes on a bigger crime-fighting role. "There is a lot of potential here," said Lawrence Kobilinsky, a DNA expert and chairman of the Department of Forensic Science at John Jay College of Criminal Justice in New York. "Any time you can develop a quick and easy screen for something ... that is a good thing." But Kobilinsky and others caution that it takes time for any new forensic test to gain acceptance where it matters most — state and federal courthouses. If the new tests begin appearing in police reports, defense attorneys can be expected to challenge their validity. "If these tests are going to get to the courtroom, which I think is inevitable, they are not going to be admissible as evidence until they can be proven reliable, accurate" and trustworthy, Kobilinsky said. "My bet is that a crime scene unit is going to be very careful about using this if it's not going to be of any benefit in litigation." |
Go for watermelons - Nature's Viagra
Washington: If you thought watermelon is just a fruit that refreshes parched throats, here is something you should know: the juicy fruit has ingredients that deliver Viagra-like effects to the body and blood vessels and may even increase libido. The finding results from a study led by an Indian researcher in the US. "We've always known that watermelon is good for you, but the list of its very important healthful benefits grows longer with each study," he added. Beneficial ingredients in watermelon and other fruits and vegetables are known as phyto-nutrients, naturally occurring compounds that are bioactive, or able to react with the human body to trigger healthy reactions, Patil said. In watermelons, these include lycopene, beta carotene and the rising star among its phyto-nutrients 'citrulline' whose beneficial functions are now being unraveled. Among them is the ability to relax blood vessels, much like Viagra does. Scientists know that when watermelon is consumed, citrulline is converted to arginine through certain enzymes. Arginine is an amino acid that works wonders on the heart and circulation system and maintains a good immune system, Patil said. "The citrulline-arginine relationship helps heart health, the immune system and may prove to be very helpful for those who suffer from obesity and type 2 diabetes," said Patil. "Arginine boosts nitric oxide, which relaxes blood vessels, the same basic effect that Viagra has, to treat erectile dysfunction and maybe even prevent it," he added. While there are many psychological and physiological problems that can cause impotence, extra nitric oxide could help those who need increased blood flow, which would also help treat angina, high blood pressure and other cardiovascular problems. "Watermelon may not be as organ specific as Viagra, but it%u2019s a great way to relax blood vessels without any drug side-effects," Patil said. The benefits of watermelon don't end there, he said. Arginine also helps the urea cycle by removing ammonia and other toxic compounds from our bodies. Citrulline, the precursor to arginine, is found in higher concentrations in the rind of watermelons than the flesh. |
Monday, June 30, 2008
Scientists develop brightest ever x-ray source
Washington: The x-ray has just got 100 million times brighter, thanks to next-generation light sources like free electron laser oscillator - or the X-FELO.
X-FELO will open up breakthrough scientific opportunities in various research fields. Its characteristics are ideally suited for bulk-sensitive, hard x-ray photo-emission spectroscopy.
Existing technology uses undulators to create bright x-ray beams of spontaneous emission at the Advanced Photon Source (APS) at Argonne.
Much of the research for x-ray free electron lasers has been concentrated on self-amplified spontaneous emission (SASE), which would amplify them by a factor of a million or more in a single pass.
A user of SASE will see x-ray brightness that is about 10,000 times brighter than what the APS is delivering, Argonne's Kwang-Je Kim said.
X-FELO, devised by US Department of Energy scientists, the electron pulse enters an undulator and generates an x-ray that is reflected back into the undulator entrance by crystals and connects with the next electron bunch and again travels back along the undulator. This pattern is repeated indefinitely with the x-ray intensity growing each time until equilibrium is reached.
An X-FELO will enhance the flux by six to eight orders of magnitude, shortening the data collection times by the same factor.
The intensity of individual x-ray pulse from an X-FELO is lower by about three orders of magnitude. However the X-FELO pulse has extremely narrow bandwidth, three to four orders of magnitude narrower than the SASE.
Accordingly an X-FELO user will see a brightness which is about six to eight orders of magnitude brighter than any previously created and three to four orders of magnitude brighter than proposed SASE technology. |
Monday, June 23, 2008
The secret to seducing a woman
The secret to seducing a woman –a touch on the arm London: Forget those cheesy pick-up lines and expensive colognes to impress a woman. The winning formula to land a hot date requires nothing but a straight look into her eyes accompanied by a light touch on her arm, according to a new study. The study, by scientists at Aberdeen University, has found that two-thirds of women gave a nod to dance with a man who requested for a dance by resting his hand on her arm for a second or two. And those who did not comply with the trick and kept their hands by their side while asking the same question had a success rate of only 50 per cent. In fact, women also preferred to give their phone-number to a man who touched their arm as he approached them in the street. Published in Focus Magazine, the study said that touching makes a man appear dominant, and henceforth more attractive to the opposite sex. In fact, researcher Dr Ben Jones said that making eye contact also indicates interest in a woman, but only if it is genuine. "Smiling can make you more attractive but it is worth bearing in mind that faking a smile is quite tricky," the Telegraph quoted Jones, as saying. And those men, who find it hard to fake a smile, are advised by Jones to take extra care of their skin, or stay amidst other women to appear more appealing. |
Formula proves 'JUNE 20' the happiest day of the year!
Dump all your sorrows and spread smiles everywhere, for June 20 has been declared the Happiest Day of the year by a leading researcher at the University of Cardiff's Centre for Lifelong Learning, London. Cliff Arnell has taken the credit for discovering today's hyper-happy potential after working out maths formula – O + (N xS) + Cpm/T + He. He devised an elaborate scientific equation based on physical, emotional and stress factors that pointed to today as the optimum time for cheer and joy. Among the factors: It's the first day of summer - which means happy memories, more time to enjoy nature and the anticipation of holidays and vacations, reports the Telegraph. O stands for being outdoors and outdoor activity, N is connection with nature, which is in full bloom now, S is socialisation with neighbours and friends, Cpm stands for childhood positive memories, T is the mean temperature which is now usually warm, and He is holiday expected. Arnall, a psychologist and former tutor at Cardiff University, said that the main aim is to 'get people talking about what makes them happy'. Arnall, who was commissioned by Walls Ice Cream to carry out the study, also calculates the most depressing day of the year which is normally around the end of January which is based on the weather, debt after Christmas, time since Christmas and motivational levels and days to pay day. |
Sunday, June 15, 2008
Bikini effect really does make men lose their heads!
Washington: If you want to make your man spend a little more money, all you
need to do is strut about in a bikini or other sexy stimuli, as such things make men extremely impulsive when it comes to taking decisions either related to money or diet.
Lead researcher Bram Van Den Bergh of Katholieke Universiteit Leuven in Belgium found that the desire for immediate rewards increased in men who touched bras, looked at pictures of beautiful women, or watched video clips of young women in bikinis running through a park.
It wasn't that the men were simply distracted by their sexual arousal, which caused them to choose more impulsively.
On the other hand, they showed improved cognition and creativity after exposure to sexy stimuli.
From the study findings, researchers concluded that there is one common appetite system in the brain monitoring our desire for a host of pleasures from sweets to pretty faces, alcohol to lotto winnings.
When it is stimulated by a sexy picture or the smell of baked goods, we experience a general craving for anything pleasant.
"Basically, you just want to be rewarded," Live Science quoted Barbara Briers, a researcher at HEC Paris School of Management, as saying.
Van Den Bergh and colleagues rendered the bikini-effect powerless by satiating the stirred appetite with a different type of reward - financial security.
A sense of personal wealth depends largely on what we perceive to be the society standard.
The researchers manipulated this perception to make male subjects feel relatively rich or relatively poor.
When a questionnaire suggested the average income in society was very small, smaller than most of the subjects' incomes, the men felt rich in comparison.
On the other hand, when the average income was implied to be very large, dwarfing that of the male subjects, most of the men began looking at their own earnings as piddling.
When the men felt well-off, the bikinis lost their influence.
However, if they considered themselves among the have-nots, they were likely to seek immediate gratification after seeing women running in bikinis. Evolution at work
Briers hypothesised, evolutionarily speaking, unfulfilled sexual arousal could trigger a subconscious belief that one's reproductive status is at stake.
Rendered fearful, men reach out for other resources, a quick payoff, fast food, to better their chances for survival.
Van Den Bergh said that the bikini effect does vary in strength from person to person.
While most men are vulnerable to subtle types of stimuli, like sexy ads and touching lingerie, others may need to see a woman nude before feeling impulsive.
No matter, Van Den Bergh warned, 'being exposed to a sexy girl may influence what stock you invest in or what candy bar you buy.'
The study is published in the Journal of Consumer Research.
Human egg formation captured in camera
Friday, 13 June , 2008,
London: A researcher associated with the Catholic University of Louvain (UCL) in Brussels has accidentally captured the images showing the production of an egg inside a woman's body, something known as 'ovulation' in medical terminology.
Jacques Donnez has revealed that he captured the event while preparing to carry out a partial hysterectomy on a 45-year-old woman.
Observing ovulation in humans is extremely rare, and previous images have been fuzzy.
"The release of the oocyte from the ovary is a crucial event in human reproduction. These pictures are clearly important to better understand the mechanism," New Scientist magazine quoted Donnez as saying.
Most scientists believe that the release of an egg occurs as a sudden, explosive event.
However, Donnez's pictures show it taking place over a period of at least 15 minutes.
The researcher says that shortly before the egg is released, enzymes break down the tissue in the mature follicle, a fluid-filled sac on the surface of the ovary that contains the egg.
He says that this prompts the formation of a reddish protrusion, and after a while a hole appears, from which the egg emerges, surrounded by support cells.
Donnez says that it then enters a Fallopian tube, which carries it to the uterus.
He admits that there are no immediate medical implications from the pictures.
However, Australian researcher Darryl Russell, who researches reproductive health at the University of Adelaide, calls the images remarkable.
"In animals, even when we control hormone levels - allowing us to predict the time at which ovulation will occur - it is very rare to see it in progress," Russell says.
The images captured by Donnez will be published in Fertility and Sterility.
London: A researcher associated with the Catholic University of Louvain (UCL) in Brussels has accidentally captured the images showing the production of an egg inside a woman's body, something known as 'ovulation' in medical terminology.
Jacques Donnez has revealed that he captured the event while preparing to carry out a partial hysterectomy on a 45-year-old woman.
Observing ovulation in humans is extremely rare, and previous images have been fuzzy.
"The release of the oocyte from the ovary is a crucial event in human reproduction. These pictures are clearly important to better understand the mechanism," New Scientist magazine quoted Donnez as saying.
Most scientists believe that the release of an egg occurs as a sudden, explosive event.
However, Donnez's pictures show it taking place over a period of at least 15 minutes.
The researcher says that shortly before the egg is released, enzymes break down the tissue in the mature follicle, a fluid-filled sac on the surface of the ovary that contains the egg.
He says that this prompts the formation of a reddish protrusion, and after a while a hole appears, from which the egg emerges, surrounded by support cells.
Donnez says that it then enters a Fallopian tube, which carries it to the uterus.
He admits that there are no immediate medical implications from the pictures.
However, Australian researcher Darryl Russell, who researches reproductive health at the University of Adelaide, calls the images remarkable.
"In animals, even when we control hormone levels - allowing us to predict the time at which ovulation will occur - it is very rare to see it in progress," Russell says.
The images captured by Donnez will be published in Fertility and Sterility.
Thursday, June 12, 2008
How Much Sleep Do You Really Need?
Single-horned 'Unicorn' deer found in Italy
Single-horned 'Unicorn' deer found in Italy This updated photo provided by the Center of Natural Sciences in Prato, Italy, Wednesday, June 11, 2008, shows a deer with a single horn in the center of its head. The one-year-old Roe Deer - nicknamed 'Unicorn'' - was born in captivity in the research center's park in the Tuscan town of Prato, near Florence, Gilberto Tozzi, director of the Center of Natural Sciences, said. He is believed to have been born with a genetic flaw; his twin has two horns.(AP Photo/Center of Natural Sciences, ho)
By MARTA FALCONI, Associated Press Writer Wed Jun 11, 3:06 PM ET ROME - A deer with a single horn in the center of its head — much like the fabled, mythical unicorn — has been spotted in a nature preserve in Italy, park officials said Wednesday. "This is fantasy becoming reality," Gilberto Tozzi, director of the Center of Natural Sciences in Prato, told The Associated Press. "The unicorn has always been a mythological animal." The 1-year-old Roe Deer — nicknamed "Unicorn" — was born in captivity in the research center's park in the Tuscan town of Prato, near Florence, Tozzi said. He is believed to have been born with a genetic flaw; his twin has two horns. Calling it the first time he has seen such a case, Tozzi said such anomalies among deer may have inspired the myth of the unicorn. The unicorn, a horse-like creature with magical healing powers, has appeared in legends and stories throughout history, from ancient and medieval texts to the adventures of Harry Potter. "This shows that even in past times, there could have been animals with this anomaly," he said by telephone. "It's not like they dreamed it up." Single-horned deer are rare but not unheard of — but even more unusual is the central positioning of the horn, experts said. "Generally, the horn is on one side (of the head) rather than being at the center. This looks like a complex case," said Fulvio Fraticelli, scientific director of Rome's zoo. He said the position of the horn could also be the result of a trauma early in the animal's life. Other mammals are believed to contribute to the myth of the unicorn, including the narwhal, a whale with a long, spiraling tusk. |
Friday, June 6, 2008
Key to All Optical Illusions Discovered
Key to All Optical Illusions Discovered
Jeanna Bryner (Senior Writer-LiveScience.com)
In this so-called Hering illusion, the straight lines near the central point (vanishing point) appear to curve outward. This illusion occurs because our brains are predicting the way the underlying scene would look in the next moment if we were moving toward the middle point. Credit: Mark Changizi, RPI.
Humans can see into the future, says a cognitive scientist. It's nothing like the alleged predictive powers of Nostradamus, but we do get a glimpse of events one-tenth of a second before they occur.
And the mechanism behind that can also explain why we are tricked by optical illusions.
Researcher Mark Changizi of Rensselaer Polytechnic Institute in New York says it starts with a neural lag that most everyone experiences while awake. When light hits your retina, about one-tenth of a second goes by before the brain translates the signal into a visual perception of the world.
Scientists already knew about the lag, yet they have debated over exactly how we compensate, with one school of thought proposing our motor system somehow modifies our movements to offset the delay.
Changizi now says it's our visual system that has evolved to compensate for neural delays, generating images of what will occur one-tenth of a second into the future. That foresight keeps our view of the world in the present. It gives you enough heads up to catch a fly ball (instead of getting socked in the face) and maneuver smoothly through a crowd. His research on this topic is detailed in the May/June (2008) issue of the journal Cognitive Science,
Explaining illusions
That same seer ability can explain a range of optical illusions, Changizi found.
"Illusions occur when our brains attempt to perceive the future, and those perceptions don't match reality," Changizi said.
Here's how the foresight theory could explain the most common visual illusions - geometric illusions that involve shapes: Something called the Hering illusion, for instance, looks like bike spokes around a central point, with vertical lines on either side of this central, so-called vanishing point. The illusion tricks us into thinking we are moving forward, and thus, switches on our future-seeing abilities. Since we aren't actually moving and the figure is static, we misperceive the straight lines as curved ones.
"Evolution has seen to it that geometric drawings like this elicit in us premonitions of the near future," Changizi said. "The converging lines toward a vanishing point (the spokes) are cues that trick our brains into thinking we are moving forward - as we would in the real world, where the door frame (a pair of vertical lines) seems to bow out as we move through it - and we try to perceive what that world will look like in the next instant."
Grand unified theory
In real life, when you are moving forward, it's not just the shape of objects that changes, he explained. Other variables, such as the angular size (how much of your visual field the object takes up), speed and contrast between the object and background, will also change.
For instance, if two objects are about the same distance in front of you, and you move toward one of the objects, that object will speed up more in the next moment, appear larger, have lower contrast (because something that is moving faster gets more blurred), and literally get nearer to you compared with the other object.
Changizi realized the same future-seeing process could explain several other types of illusions. In what he refers to as a "grand unified theory," Changizi organized 50 kinds of illusions into a matrix of 28 categories. The results can successfully predict how certain variables, such as proximity to the central point or size, will be perceived.
Changizi says that finding a theory that works for so many different classes of illusions is "a theorist's dream."
Most other ideas put forth to explain illusions have explained one or just a few types, he said.
The theory is "a big new player in the debate about the origins of illusions," Changizi told LiveScience. "All I'm hoping for is that it becomes a giant gorilla on the block that can take some punches."
Jeanna Bryner (Senior Writer-LiveScience.com)
In this so-called Hering illusion, the straight lines near the central point (vanishing point) appear to curve outward. This illusion occurs because our brains are predicting the way the underlying scene would look in the next moment if we were moving toward the middle point. Credit: Mark Changizi, RPI.
In the Orbison illusion, the squares closer to the image's center seem larger than the outside squares. The radiating lines and center point trick us into thinking we are moving forward toward the center point. The result is a perception of what the image would look like a tenth of a second into the future. Credit: Mark Changizi, RPI.
In this illusion, looming toward the center leads to the brightness expanding outward, while looming away does the opposite. Credit: Mark Changizi, RPI
Humans can see into the future, says a cognitive scientist. It's nothing like the alleged predictive powers of Nostradamus, but we do get a glimpse of events one-tenth of a second before they occur.
And the mechanism behind that can also explain why we are tricked by optical illusions.
Researcher Mark Changizi of Rensselaer Polytechnic Institute in New York says it starts with a neural lag that most everyone experiences while awake. When light hits your retina, about one-tenth of a second goes by before the brain translates the signal into a visual perception of the world.
Scientists already knew about the lag, yet they have debated over exactly how we compensate, with one school of thought proposing our motor system somehow modifies our movements to offset the delay.
Changizi now says it's our visual system that has evolved to compensate for neural delays, generating images of what will occur one-tenth of a second into the future. That foresight keeps our view of the world in the present. It gives you enough heads up to catch a fly ball (instead of getting socked in the face) and maneuver smoothly through a crowd. His research on this topic is detailed in the May/June (2008) issue of the journal Cognitive Science,
Explaining illusions
That same seer ability can explain a range of optical illusions, Changizi found.
"Illusions occur when our brains attempt to perceive the future, and those perceptions don't match reality," Changizi said.
Here's how the foresight theory could explain the most common visual illusions - geometric illusions that involve shapes: Something called the Hering illusion, for instance, looks like bike spokes around a central point, with vertical lines on either side of this central, so-called vanishing point. The illusion tricks us into thinking we are moving forward, and thus, switches on our future-seeing abilities. Since we aren't actually moving and the figure is static, we misperceive the straight lines as curved ones.
"Evolution has seen to it that geometric drawings like this elicit in us premonitions of the near future," Changizi said. "The converging lines toward a vanishing point (the spokes) are cues that trick our brains into thinking we are moving forward - as we would in the real world, where the door frame (a pair of vertical lines) seems to bow out as we move through it - and we try to perceive what that world will look like in the next instant."
Grand unified theory
In real life, when you are moving forward, it's not just the shape of objects that changes, he explained. Other variables, such as the angular size (how much of your visual field the object takes up), speed and contrast between the object and background, will also change.
For instance, if two objects are about the same distance in front of you, and you move toward one of the objects, that object will speed up more in the next moment, appear larger, have lower contrast (because something that is moving faster gets more blurred), and literally get nearer to you compared with the other object.
Changizi realized the same future-seeing process could explain several other types of illusions. In what he refers to as a "grand unified theory," Changizi organized 50 kinds of illusions into a matrix of 28 categories. The results can successfully predict how certain variables, such as proximity to the central point or size, will be perceived.
Changizi says that finding a theory that works for so many different classes of illusions is "a theorist's dream."
Most other ideas put forth to explain illusions have explained one or just a few types, he said.
The theory is "a big new player in the debate about the origins of illusions," Changizi told LiveScience. "All I'm hoping for is that it becomes a giant gorilla on the block that can take some punches."
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