Sunday, November 16, 2008

I thought this was what beer is for

New Beauty Machine Makes Everyone Gorgeous | LiveScience
New Beauty Machine Makes Everyone Gorgeous

By Robert Roy Britt, LiveScience Managing Editor

posted: 07 November 2008 08:29 am ET
........

Researchers have created a "beauty machine" they say can turn a woman's photo into the likeness of a cover model with the push of a button.

The goal is not just to toy with pictures. Sure, the new computer software could help editors distort magazine cover photos even more than they already do. But it could also guide plastic surgeons in efforts to achieve some perceived level of perfection in a patient.

Or the software might even be incorporated into future digital cameras to make us all appear gorgeous, the researchers suggest.

"Beauty, contrary to what most people think, is not simply in the eye of the beholder," said lead researcher Daniel Cohen-Or of the Blavatnik School of Computer Sciences at Tel Aviv University.

Attractiveness — for men or women — can be objectified by a computer and boiled down to a function of mathematical distances or ratios, Cohen-Or said, admitting that the work is likely to be controversial.

"Beauty can be quantified by mathematical measurements and ratios. It can be defined as average distances between features, which a majority of people agree are the most beautiful," he said. "I don't claim to know much about beauty. For us, every picture in this research project is just a collection of numbers."

All this is actually backed by a study, published recently in the proceedings of Siggraph, an annual computer graphics conference.

Cohen-Or and colleagues asked 68 Israeli and German men and women, ages 25 to 40, to rank the beauty of 93 different men's and women's faces on a scale of 1 to 7. The scores were entered into a database and correlated to 250 different measurements and facial features, such as ratios of the nose, chin and distance from ears to eyes, according to a statement from the team. From this, they created an algorithm of "desirable elements of attractiveness" that then spits out the new you.

The beauty machine is more subtle than a typical Photoshop makeover, they say. The machine does not seem to work so well on celebrities, however.

"We've run the faces of people like Brigitte Bardot and Woody Allen through the machine and most people are very unhappy with the results," Cohen-Or said. "But in unfamiliar faces, most would agree the output is better."

Thursday, November 13, 2008

a do-deca world

Preview: 'Buckypaper' stronger than steel, harder than diamonds
Working with a material 10 times lighter than steel - but 250 times stronger - would be a dream come true for any engineer. If this material also had amazing properties that made it highly conductive of heat and electricity, it would start to sound like something out of a science fiction novel. Yet one Florida State University research group, the Florida Advanced Center for Composite Technologies (FAC2T), is working to develop real-world applications for just such a material.

Ben Wang, a professor of industrial engineering at the Florida
A&M University-FSU College of Engineering, serves as director of
FAC2T (http://www.fac2t.eng.fsu.edu), which works to develop new, high-performance composite materials, as well as technologies for producing them.

Wang is widely acknowledged as a pioneer in the growing field of
nano-materials science. His main area of research, involving an
extraordinary material known as "buckypaper," has shown promise in a
variety of applications, including the development of aerospace
structures, the production of more-effective body armor and armored
vehicles, and the construction of next-generation computer displays.
The U.S. military has shown a keen interest in the military
applications of Wang's research; in fact, the Army Research Lab
recently awarded FAC2T a $2.5-million grant, while the Air Force Office
of Scientific Research awarded $1.2 million.

"At FAC2T, our objective is to push the envelope to find out just
how strong of a composite material we can make using buckypaper," Wang
said. "In addition, we're focused on developing processes that will
allow it to be mass-produced cheaply."

Buckypaper is made from carbon nanotubes - amazingly strong fibers
about 1/50,000th the diameter of a human hair that were first developed
in the early 1990s. Buckypaper owes its name to Buckminsterfullerene,
or Carbon 60 - a type of carbon molecule whose powerful atomic bonds
make it twice as hard as a diamond. Sir Harold Kroto, now a professor
and scientist with FSU's department of chemistry and biochemistry, and
two other scientists shared the 1996 Nobel Prize in Chemistry for their
discovery of Buckminsterfullerene, nicknamed "buckyballs" for the
molecules' spherical shape. Their discovery has led to a revolution in
the fields of chemistry and materials science - and directly
contributed to the development of buckypaper.
Among the possible uses for buckypaper that are being researched at FAC2T:

… If exposed to an electric charge, buckypaper could be used to
illuminate computer and television screens. It would be more
energy-efficient, lighter, and would allow for a more uniform level of
brightness than current cathode ray tube (CRT) and liquid crystal
display (LCD) technology.

… As one of the most thermally conductive materials known,
buckypaper lends itself to the development of heat sinks that would
allow computers and other electronic equipment to disperse heat more
efficiently than is currently possible. This, in turn, could lead to
even greater advances in electronic miniaturization.

… Because it has an unusually high current-carrying capacity, a
film made from buckypaper could be applied to the exteriors of
airplanes. Lightning strikes then would flow around the plane and
dissipate without causing damage.
… Films also could protect electronic circuits and devices within
airplanes from electromagnetic interference, which can damage equipment
and alter settings. Similarly, such films could allow military aircraft
to shield their electromagnetic "signatures," which can be detected via
radar.

FAC2T "is at the very forefront of a technological revolution that
will dramatically change the way items all around us are produced,"
said Kirby Kemper, FSU's vice president for Research. "The group of
faculty, staff, students and post-docs in this center have been
visionary in their ability to recognize the tremendous potential of
nanotechnology. The potential applications are mind-boggling."

FSU has four U.S. patents pending that are related to its buckypaper research.

In addition to his academic and scientific responsibilities, Wang
recently was named FSU's assistant vice president for Research. In this
role, he will help to advance research activities at the College of
Engineering and throughout the university.

"I look forward to bringing researchers together to pursue
rewarding research opportunities," Wang said. "We have very
knowledgeable and talented faculty and students, and I will be working
with them to help meet their full potential for advancement in their
fields."


Source: Florida State University (By Barry Ray)









This news is brought to you by PhysOrg.com


consider the lillies -reprise

Technology Review: Sun + Water = Fuel

With catalysts created by an MIT chemist, sunlight can turn water into hydrogen. If the process can scale up, it could make solar power a dominant source of energy.
By Kevin Bullis

"I'm going to show you something I haven't showed anybody yet," said Daniel Nocera, a professor of chemistry at MIT, speaking this May to an auditorium filled with scientists and U.S. government energy officials. He asked the house manager to lower the lights. Then he started a video. "Can you see that?" he asked excitedly, pointing to the bubbles rising from a strip of material immersed in water. "Oxygen is pouring off of this electrode." Then he added, somewhat cryptically, "This is the future. We've got the leaf."

What Nocera was demonstrating was a reaction that generates oxygen from water much as green plants do during photosynthesis--an achievement that could have profound implications for the energy debate. Carried out with the help of a catalyst he developed, the reaction is the first and most difficult step in splitting water to make hydrogen gas. And efficiently generating hydrogen from water, Nocera believes, will help surmount one of the main obstacles preventing solar power from becoming a dominant source of electricity: there's no cost-effective way to store the energy collected by solar panels so that it can be used at night or during cloudy days.

Solar power has a unique potential to generate vast amounts of clean energy that doesn't contribute to global warming. But without a cheap means to store this energy, solar power can't replace fossil fuels on a large scale. In Nocera's scenario, sunlight would split water to produce versatile, easy-to-store hydrogen fuel that could later be burned in an internal-combustion generator or recombined with oxygen in a fuel cell. Even more ambitious, the reaction could be used to split seawater; in that case, running the hydrogen through a fuel cell would yield fresh water as well as electricity.

Storing energy from the sun by mimicking photosynthesis is something scientists have been trying to do since the early 1970s. In particular, they have tried to replicate the way green plants break down water. Chemists, of course, can already split water. But the process has required high temperatures, harsh alkaline solutions, or rare and expensive catalysts such as platinum. What Nocera has devised is an inexpensive catalyst that produces oxygen from water at room temperature and without caustic chemicals--the same benign conditions found in plants. Several other promising catalysts, including another that Nocera developed, could be used to complete the process and produce hydrogen gas.

Nocera sees two ways to take advantage of his breakthrough. In the first, a conventional solar panel would capture sunlight to produce electricity; in turn, that electricity would power a device called an electrolyzer, which would use his catalysts to split water. The second approach would employ a system that more closely mimics the structure of a leaf. The catalysts would be deployed side by side with special dye molecules designed to absorb sunlight; the energy captured by the dyes would drive the water-splitting reaction. Either way, solar energy would be converted into hydrogen fuel that could be easily stored and used at night--or whenever it's needed.

Nocera's audacious claims for the importance of his advance are the kind that academic chemists are usually loath to make in front of their peers. Indeed, a number of experts have questioned how well his system can be scaled up and how economical it will be. But Nocera shows no signs of backing down. "With this discovery, I totally change the dialogue," he told the audience in May. "All of the old arguments go out the window."

The Dark Side of Solar
Sunlight is the world's largest potential source of renewable energy, but that potential could easily go unrealized. Not only do solar panels not work at night, but daytime production waxes and wanes as clouds pass overhead. That's why today most solar panels--both those in solar farms built by utilities and those mounted on the roofs of houses and businesses--are connected to the electrical grid. During sunny days, when solar panels are operating at peak capacity, homeowners and companies can sell their excess power to utilities. But they generally have to rely on the grid at night, or when clouds shade the panels.

This system works only because solar power makes such a tiny contribution to overall electricity production: it meets a small fraction of 1 percent of total demand in the United States. As the contribution of solar power grows, its unreliability will become an increasingly serious problem.

If solar power grows enough to provide as little as 10 percent of total electricity, utilities will need to decide what to do when clouds move in during times of peak demand, says Ryan Wiser, a research scientist who studies electricity markets at Lawrence Berkeley National Laboratory in Berkeley, CA. Either utilities will need to operate extra natural-gas plants that can quickly ramp up to compensate for the lost power, or they'll need to invest in energy storage. The first option is currently cheaper, Wiser says: "Electrical storage is just too expensive."

But if we count on solar energy for more than about 20 percent of total electricity, he says, it will start to contribute to what's called base load power, the amount of power necessary to meet minimum demand. And base load power (which is now supplied mostly by coal-fired plants) must be provided at a relatively constant rate. Solar energy can't be harnessed for this purpose unless it can be stored on a large scale for use 24 hours a day, in good weather and bad.

In short, for solar to become a primary source of electricity, vast amounts of affordable storage will be needed. And today's options for storing electricity just aren't practical on a large enough scale, says Nathan Lewis, a professor of chemistry at Caltech. Take one of the least expensive methods: using electricity to pump water uphill and then running the water through a turbine to generate elec­tricity later on. One kilogram of water pumped up 100 meters stores about a kilojoule of energy. In comparison, a kilogram of gasoline stores about 45,000 kilojoules. Storing enough energy this way would require massive dams and huge reservoirs that would be emptied and filled every day. And try finding enough water for that in places such as Arizona and Nevada, where sunlight is particularly abundant.

Batteries, meanwhile, are expensive: they could add $10,000 to the cost of a typical home solar system. And although they're improving, they still store far less energy than fuels such as gasoline and hydrogen store in the form of chemical bonds. The best batteries store about 300 watt-hours of energy per kilogram, Lewis says, while gasoline stores 13,000 watt-hours per kilogram. "The numbers make it obvious that chemical fuels are the only energy-dense way to obtain massive energy storage," Lewis says. Of those fuels, not only is hydrogen potentially cleaner than gasoline, but by weight it stores much more energy--about three times as much, though it takes up more space because it's a gas.

The challenge lies in using energy from the sun to make such fuels cheaply and efficiently. This is where Nocera's efforts to mimic photosynthesis come in.

Imitating Plants
In real photosynthesis, green plants use chlorophyll to capture energy from sunlight and then use that energy to drive a series of complex chemical reactions that turn water and carbon dioxide into energy-rich carbohydrates such as starch and sugar. But what primarily interests many researchers is an early step in the process, in which a combination of proteins and inorganic catalysts helps break water efficiently into oxygen and hydrogen ions.

The field of artificial photosynthesis got off to a quick start. In the early 1970s, a graduate student at the University of Tokyo, Akira Fujishima, and his thesis advisor, Kenichi Honda, showed that electrodes made from titanium dioxide--a component of white paint--would slowly split water when exposed to light from a bright, 500-watt xenon lamp. The finding established that light could be used to split water outside of plants. In 1974, Thomas Meyer, a professor of chemistry at the University of North Caro­lina, Chapel Hill, showed that a ruthenium-based dye, when exposed to light, underwent chemical changes that gave it the potential to oxidize water, or pull electrons from it--the key first step in water splitting.

Ultimately, neither technique proved practical. The titanium dioxide couldn't absorb enough sunlight, and the light-induced chemical state in Meyer's dye was too transient to be useful. But the advances stimu­lated the imaginations of scientists. "You could look ahead and see where to go and, at least in principle, put the pieces together," Meyer says.

Over the next few decades, scientists studied the structures and materials in plants that absorb sunlight and store its energy. They found that plants carefully choreograph the movement of water molecules, electrons, and hydrogen ions--that is, protons. But much about the precise mechanisms involved remained unknown. Then, in 2004, researchers at Imperial College London identified the structure of a group of proteins and metals that is crucial for freeing oxygen from water in plants. They showed that the heart of this catalytic complex was a collection of proteins, oxygen atoms, and manganese and calcium ions that interact in specific ways.

"As soon as we saw this, we could start designing systems," says Nocera, who had been trying to fully understand the chemistry behind photosynthesis since 1984. Reading this "road map," he says, his group set out to manage protons and electrons somewhat the way plants do--but using only inorganic materials, which are more robust and stable than proteins.

Initially, Nocera didn't tackle the biggest challenge, pulling oxygen out from water. Rather, "to get our training wheels," he began with the reverse reaction: combining oxygen with protons and electrons to form water. He found that certain complex compounds based on cobalt were good catalysts for this reaction. So when it came time to try splitting water, he decided to use similar cobalt compounds.

Nocera knew that working with these compounds in water could be a problem, since cobalt can dissolve. Not surprisingly, he says, "within days we realized that cobalt was falling out of this elaborate compound that we made." With his initial attempts foiled, he decided to take a different approach. Instead of using a complex compound, he tested the catalytic activity of dissolved cobalt, with some phosphate added to the water to help the reaction. "We said, let's forget all the elaborate stuff and just use cobalt directly," he says.

The experiment worked better than Nocera and his colleagues had expected. When a current was applied to an electrode immersed in the solution, cobalt and phosphate accumulated on it in a thin film, and a dense layer of bubbles started forming in just a few minutes. Further tests confirmed that the bubbles were oxygen released by splitting the water. "Here's the luck," Nocera says. "There was no reason for us to expect that just plain cobalt with phosphate, versus cobalt being tied up in one of our complexes, would work this well. I couldn't have predicted it. The stuff that was falling out of the compounds turned out to be what we needed.

"Now we want to understand it," he continues. "I want to know why the hell cobalt in this thin film is so active. I may be able to improve it or use a different metal that's better." At the same time, he wants to start working with engineers to optimize the process and make an efficient water-splitting cell, one that incorporates catalysts for generating both oxygen and hydrogen. "We were really interested in the basic science. Can we make a catalyst that works efficiently under the conditions of photosynthesis?" he says. "The answer now is yes, we can do that. Now we've really got to get to the technology of designing a cell."

Catalyzing a Debate
Nocera's discovery has garnered a lot of attention, and not all of it has been flattering. Many chemists find his claims overstated; they don't dispute his findings, but they doubt that they will have the consequences he imagines. "The claim that this is the answer for artificial photosynthesis is crazy," says Thomas Meyer, who has been a mentor to Nocera. He says that while Nocera's catalysts "could prove technologically important," the advance is "a research finding," and there's "no guarantee that it can be scaled up or even made practical."

Many critics' objections revolve around the inability of ­Nocera's lab setup to split water nearly as rapidly as commercial electrolyzers do. The faster the system, the smaller a commercial unit that produced a given amount of hydrogen and oxygen would be. And smaller systems, in general, are cheaper.

The way to compare different catalysts is to look at their "current density"--that is, electrical current per square centimeter--when they're at their most efficient. The higher the current, the faster the catalyst can produce oxygen. Nocera reported results of 1 milliamp per square centimeter, although he says he's achieved 10 milliamps since then. Commercial electrolyzers typically run at about 1,000 milliamps per square centimeter. "At least what he's published so far would never work for a commercial electrolyzer, where the current density is 800 times to 2,000 times greater," says John Turner, a research fellow at the National Renewable Energy Laboratory in Golden, CO.

Other experts question the whole principle of converting sunlight into electricity, then into a chemical fuel, and then back into electricity again. They suggest that while batteries store far less energy than chemical fuels, they are nevertheless far more efficient, because using electricity to make fuels and then using the fuels to generate electricity wastes energy at every step. It would be better, they say, to focus on improving battery technology or other similar forms of electrical storage, rather than on developing water splitters and fuel cells. As Ryan Wiser puts it, "Electrolysis is [currently] inefficient, so why would you do it?"

The Artificial Leaf
Michael Grätzel, however, may have a clever way to turn Nocera's discovery to practical use. A professor of chemistry and chemical engineering at the École Polytechnique Fédérale in Lausanne, Switzerland, he was one of the first people Nocera told about his new catalyst. "He was so excited," Grätzel says. "He took me to a restaurant and bought a tremendously expensive bottle of wine."

In 1991, Grätzel invented a promising new type of solar cell. It uses a dye containing ruthenium, which acts much like the chlorophyll in a plant, absorbing light and releasing electrons. In ­Grätzel's solar cell, however, the electrons don't set off a water-splitting reaction. Instead, they're collected by a film of titanium dioxide and directed through an external circuit, generating electricity. Grätzel now thinks that he can integrate his solar cell and ­Nocera's catalyst into a single device that captures the energy from sunlight and uses it to split water.

If he's right, it would be a significant step toward making a device that, in many ways, truly resembles a leaf. The idea is that Grätzel's dye would take the place of the electrode on which the catalyst forms in Nocera's system. The dye itself, when exposed to light, can generate the voltage needed to assemble the catalyst. "The dye acts like a molecular wire that conducts charges away," Grätzel says. The catalyst then assembles where it's needed, right on the dye. Once the catalyst is formed, the sunlight absorbed by the dye drives the reactions that split water. Grätzel says that the device could be more efficient and cheaper than using a separate solar panel and electrolyzer.

Another possibility that Nocera is investigating is whether his catalyst can be used to split seawater. In initial tests, it performs well in the presence of salt, and he is now testing it to see how it handles other compounds found in the sea. If it works, Nocera's system could address more than just the energy crisis; it could help solve the world's growing shortage of fresh water as well.

Artificial leaves and fuel-producing desalination systems might sound like grandiose promises. But to many scientists, such possibilities seem maddeningly close; chemists seeking new energy technologies have been taunted for decades by the fact that plants easily use sunlight to turn abundant materials into energy-rich molecules. "We see it going on all around us, but it's something we can't really do," says Paul Alivisatos, a professor of chemistry and materials science at the University of California, Berkeley, who is leading an effort at Lawrence Berkeley National Laboratory to imitate photosynthesis by chemical means.

But soon, using nature's own blueprint, human beings could be using the sun "to make fuels from a glass of water," as Nocera puts it. That idea has an elegance that any chemist can appreciate--and possibilities that everyone should find hopeful.

Kevin Bullis is Technology Review's Energy Editor.

untangling the web we weave

Technology Review: Untangling Web Information
Tuesday, October 21, 2008
Untangling Web Information
The Semantic Web organizer Twine offers bookmarking with built-in AI.
By Erica Naone

The next big stage in the evolution of the Internet, according to many experts and luminaries, will be the advent of the Semantic Web--that is, technologies that let computers process the meaning of Web pages instead of simply downloading or serving them up blindly. Microsoft's acquisition of the semantic search engine Powerset earlier this year shows faith in this vision. But thus far, little Semantic Web technology has been available to the general public. That's why many eyes will be on Twine, a Web organizer based on semantic technology that launches publicly today.

Developed by Radar Networks, based in San Francisco, Twine is part bookmarking tool, part social network, and part recommendation engine, helping users collect, manage, and share online information related to any area of interest. For the novice, it can be tricky figuring out exactly where to start. But for experienced users, Twine can be a powerful way to research a subject collaboratively or find people with common interests, with the usual features of a bookmarking site augmented by Twine's underlying semantic technology.

After creating an account, a user adds a Twine bookmarklet to her browser's bookmarks, then adds items to her Twine page by clicking the bookmarklet as she surfs the Web. Bookmarks, too, can easily be imported from a browser or from another Web bookmarking service.

Twine uses artificial intelligence--machine learning and natural language processing--to parse the contents of Web pages and extract key concepts, such as people, places, and organizations, from the pages that a user saves. The site then uses these concepts to link information and users. For example, creating a twine--a bundle of bookmarks related to a particular topic--devoted to a specialized technique in computer game design quickly led to the discovery of twines (created by other users) devoted to other areas of game design and to twines devoted to a popular game that uses the technique. It also led to other users interested in the subject. Twine is also meant to automatically generate tags, descriptions, and summaries of bookmarked Web pages. In the preview, or beta, version, this feature didn't always work properly, but Nova Spivack, CEO of Radar Networks, says that the functionality has been improved ahead of the public launch. Twines offer a hub for collecting, sharing, and discussing information. For example, users have created twines devoted to twentieth-century music, science and technology, philosophy, and cool things found around the Web.

On the surface, Twine looks a lot like many other social-networking applications: users make connections, share, and discuss information, and the artificial intelligence, machine learning, and natural language processing built into the website is not immediately obvious. "The Semantic Web is a technology that's useful. It's a means to an end, not an end in itself," says Spivack. "What we're doing with this release and going forward is, we're talking about what you can use Twine for, and the fact that it's powered by the Semantic Web is a detail for geeks."

But Jim Hendler, a professor of computer science at Rensselaer Polytechnic Institute and a member of Twine's advisory board, says that Semantic Web technologies can set Twine apart from other social-networking sites. This could be true, so long as users learn to take advantage of those technologies by paying attention to recommendations and following the threads that Twine offers them. Users could easily miss this, however, by simply throwing bookmarks into Twine without getting involved in public twines or connecting to other users.

It would be nice to be able to use Twine for a few more specialized purposes. For example, it seems ideal for finding events related to areas of interest--indie rock bands playing in Boston, for example. But the current interface deals awkwardly with dates. A Twine calendar, which categorizes events intelligently, would be a logical extension of the service. Spivack says that such a feature, as well as further developments, are on the way. As these arrive, and as the company adds more ways to classify data, the real value of the Semantic Web could well start to surface.

consider the lillies


The Greek Fragments of the Gospel of Thomas - Saying 36 - By Andrew Bernhard

you CAN break your penis

http://www.medicinenet.com

5 Things You Didn't Know About Your Penis

Medical experts reveal interesting facts that men and women will find educational -- and surprising.

By Martin F. Downs
WebMD Feature

Reviewed by Louise Chang, MD


Here are some things you might have wondered about your penis, but were afraid to ask.

No. 1: Your Penis Does Have a Mind of Its Own

You've probably noticed that your penis often does its own thing. You may remember times when it was completely inappropriate to have an erection; and yet you couldn\'t wish it away.

It's true that you have less command over your penis than body parts like your arms and legs. That's because the penis answers to a part of the nervous system that\'s not always under your conscious control. This is called the autonomic nervous system, which also regulates heart rate and blood pressure.

Sexual arousal usually isn't voluntary. The conscious mind is complicit in it, but a lot of sexual arousal goes on in the sympathetic nervous system. In addition, impulses from the brain during the REM phase of sleep cause erections, whether you're dreaming about sex or about a test you forgot to study for. Heavy lifting or straining to have a bowel movement can also produce an erection.

Just as the penis grows without your consent, sometimes it shrinks. "The flaccid penis varies in size considerably within a given man," says Drogo Montague, MD, a urologist at the Cleveland Clinic. Exposure to cold water or air makes your penis shrink. That's a function of the sympathetic nervous system.

Psychological stress also involves the sympathetic nervous system, and stress has the same effect as a cold shower, Montague says. When you're relaxed and feeling well, your flaccid penis looks bigger than when you're stressed out.

The penis is "kind of a barometer of the sympathetic nervous system," Montague says. So the greeting, "How's it hanging?" is more apt than you might have realized.

No. 2: Your Penis May Be a 'Grower' or a 'Show-er'

Among men, there is no consistent relationship between the size of the flaccid penis and its full erect length.

In one study of 80 men, researchers found that increases from flaccid to erect lengths ranged widely, from less than a quarter inch to 3.5 inches longer.

Whatever the clinical significance of these data may be, the locker-room significance is considerable. You can't assume that a dude with a big limp penis gets much bigger with an erection. And the guy whose penis looks tiny could surprise you with a big erection.

An analysis of more than thousand measurements taken by sex researcher Alfred Kinsey shows that shorter flaccid penises tend to gain about twice as much length as longer flaccid penises.

A penis that doesn't gain much length with an erection has become known as a "show-er," and a penis that gains a lot is said to be a "grower." These are not medical terms, and there aren't scientifically established thresholds for what's a show-er or a grower.

Kinsey's data suggest that most penises aren't extreme show-ers or growers. About 12% of penises gained one-third or less of their total length with an erection, and about 7% doubled in length when erect.

No. 3: Your Penis Is Shaped Like a Boomerang

Your penis is shaped like a boomerang. Just like you don't see all of a big oak tree above ground, you don't see the root of your penis tucked up inside your pelvis and attached to your pubic bone.

In an MRI picture, the penis looks distinctly boomerang-like, as noted by a French researcher who studied men and women having sex inside an MRI scanner.

One method of surgical "penis enlargement" is to cut the ligament that holds the root of the penis up inside the pelvis. This operation may give some men a little extra length if more of the penis protrudes from the body, but there are side effects. This ligament, called the suspensory ligament, makes an erection sturdy. With that ligament cut, the erect penis loses its upward angle and it wobbles at the base. The lack of sturdiness can lead to injury.

No. 4: You Can Break Your Penis

There is no "penis bone," but you can break your penis all the same. It's called penile fracture, and it's not a subtle injury. When it happens, there's "an audible pop or snap," Montague says. Then the penis turns black and blue. And there's terrible pain.

Penile fracture is rare, and it typically happens to younger men because their erections tend to be quite rigid.

Here's how to avoid penile fracture: don't use your penis too roughly. A common way that penile fracture happens, Montague says, is when a man is thrusting too hard and fast during sex, and slams into his partner's pubic bone. Also, a woman who moves wildly while on top of a man during sex can break a man's penis.

Peyronie's syndrome is a related condition that tends to show up more in older men, Montague says. An older man's erection may not be as rigid, but still is hard enough for sex. Over time, if the penis bends too much a certain way during sex, small tears in the tissue can form scars, and the accumulated scar tissue gives the penis an abnormally curved shape.

Not all penis curvature is a problem, however. "There is a lot of variability in what normal is," Cummings says.

No. 5: Most Penises in the World Are Uncut

A report by the World Health Organization (WHO) and the Joint United Nations Programme on HIV/AIDS (UNAIDS) estimates that worldwide only 30% of males aged 15 and up are circumcised.

Rates vary greatly depending upon religion and nationality. Almost all Jewish and Muslim males in the world have circumcised penises, and together they account for about 70% of all circumcised males globally.

The United States has the highest proportion of males circumcised for non-religious reasons. A whopping 75% of non-Jewish, non-Muslim American men are circumcised. Compare that to Canada, where only 30% are. In the U.K. it's 20%; in Australia it's merely 6%.

The practice of circumcising baby boys for medical and cosmetic reasons has become controversial in the U.S. But recently the World Health Organization (WHO) and the UUNAIDS recommended circumcision for adult men, based upon evidence that men with circumcised penises have a lower risk of being infected with HIV.

The CDC estimates that about 65% of all newborn boys get circumcised in the U.S.

SOURCES:
Drogo Montague, MD, director, Center for Genitourinary Reconstruction, Glickman Urological and Kidney Institute, Cleveland Clinic.
James Cummings, MD, chief, division of urology, Saint Louis University School of Medicine. Masters and Johnson. Human Sexual Response, Little, Brown, 1966.
Wessels, H. Journal of Urology, September 1996; vol 156: pp 996-997.
Jamison, P. Journal of Sex Research, 1988; vol 24: pp 177-183.
Faix, A. Journal of Sex and Marital Therapy, 2002; vol 28: pp 63-76.
WHO and UNAIDS: Male circumcision: Global trends and determinants of prevalence, safety and acceptability, February 2007.
WebMD Medical News: "Circumcision: New Weapon Against AIDS?"
CDC.
Reviewed on March 18, 2008

your guide to masturbation

Your Guide to Masturbation

* Introduction to masturbation
* Who masturbates?
* Why do people masturbate?
* Is masturbation normal?
* Is masturbation harmful?

Introduction to Masturbation

Masturbation is the self-stimulation of the genitals to achieve sexual arousal and pleasure, usually to the point of orgasm (sexual climax). It is commonly done by touching, stroking, or massaging the penis or clitoris until an orgasm is achieved. Some women also use stimulation of the vagina to masturbate or use \"sex toys,\" such as a vibrator.

Who Masturbates?

Just about everybody. Masturbation is a very common behavior, even among people who have sexual relations with a partner. In one national study, 95% of males and 89% of females reported that they have masturbated. Masturbation is the first sexual act experienced by most males and females. In young children, masturbation is a normal part of the growing child\'s exploration of his or her body. Most people continue to masturbate in adulthood, and many do so throughout their lives.

Why Do People Masturbate?

In addition to feeling good, masturbation is a good way of relieving the sexual tension that can build up over time, especially for people without partners or whose partners are not willing or available for sex. Masturbation also is a safe sexual alternative for people who wish to avoid pregnancy and the dangers of sexually transmitted diseases. It also is necessary when a man must give a semen sample for infertility testing or for sperm donation. When sexual dysfunction is present in an adult, masturbation may be prescribed by a sex therapist to allow a person to experience an orgasm (often in women) or to delay its arrival (often in men).

Is Masturbation Normal?

While it once was regarded as a perversion and a sign of a mental problem, masturbation now is regarded as a normal, healthy sexual activity that is pleasant, fulfilling, acceptable and safe. It is a good way to experience sexual pleasure and can be done throughout life.

Masturbation is only considered a problem when it inhibits sexual activity with a partner, is done in public, or causes significant distress to the person. It may cause distress if it is done compulsively and/or interferes with daily life and activities.

Is Masturbation Harmful?

In general, the medical community considers masturbation to be a natural and harmless expression of sexuality for both men and women. It does not cause any physical injury or harm to the body, and can be performed in moderation throughout a person\'s lifetime as a part of normal sexual behavior. Some cultures and religions oppose the use of masturbation or even label it as sinful. This can lead to guilt or shame about the behavior.

Some experts suggest that masturbation can actually improve sexual health and relationships. By exploring your own body through masturbation, you can determine what is erotically pleasing to you and can share this with your partner. Some partners use mutual masturbation to discover techniques for a more satisfying sexual relationship and to add to their mutual intimacy.

Reviewed by the doctors at The Cleveland Clinic Department of Obstetrics and Gynecology.

Reviewed by Robert S. Phillips, MD on July 08, 2008

is it a problem if it doesn't bother you?

Almost Half of Women Have Sexual Problems
By Amanda Gardner
HealthDay Reporter

FRIDAY, Oct. 31 (HealthDay News) -- In a double whammy for the female gender, new research shows that 40% of women report sexual problems, but only 12% are distressed about it.
\"The good news is that 12% is a very different number than 40%,\" said study author Dr. Jan Shifren, an associate professor of obstetrics, gynecology and reproductive biology at Harvard Medical School and director of the Vincent Menopause Program at Massachusetts General Hospital, both in Boston.

But 12% of 83 million U.S. women aged 20 to 65 is nothing to scoff at, noted a related editorial in the November issue of Obstetrics & Gynecology. The research was funded by Boehringer Ingelheim International, maker of flibanserin, a drug for female sexual dysfunction that is currently being tested in clinical trials.

Previous surveys have reported similar estimates of female sexual dysfunction, including low desire and problems with orgasm. The most widely quoted figure, from the U.S. National Health and Social Life Survey, is 43%.

However, few of those surveys have looked at distress, despite the fact that the American Psychiatric Association and U.S. Food and Drug Administration\'s guidelines require such distress as part of the diagnostic criteria.

This study included almost 32,000 female respondents aged 18 and older.

Overall, 43.1% of those surveyed reported some kind of sexual problem: 39% reported diminished desire, 26% reported problems with arousal, and 21% problems with achieving orgasm.

Only 12%, however, reported significant personal distress associated with this problem.

And there were age differences. \"The highest prevalence of sexual dysfunction was in older women, but they experienced less associated distress,\" Shifren said. \"The most distress occurred at mid-life, and the youngest women had the lowest prevalence of problems and of associated distress.\"

Although the study did not specifically look at why older women had more problems yet less distress about them, the authors postulated that reasons could include partner changes, other medical problems, or problems with their partners health.

Women currently experiencing depression had more than double the risk of having distressing sexual problems when compared with non-depressed women. While conditions such as diabetes, high blood pressure and cardiovascular disease affect men\'s sexual health, none of these issues impacted women\'s sexual health in this study.

\"This is a wake-up call to health-care professionals . . . of the importance of sexual health and sexual quality of life,\" said Sheryl Kingsberg, chief of the division of behavioral medicine at MacDonald Women\'s Hospital, University Hospitals Case Medical Center in Cleveland. \"Forty percent of patients have sexual concerns, and 12% have enough of a concern that it\'s a significant dysfunction in life. This needs to be addressed.\"

While clinical psychologists and other mental health professionals as well as sex therapists have been working with couples on these issues for decades, medical options, including flibanserin, are now also on the horizon.

\"There is research going on, and my hope is that women are finally going to have some options when it comes to sexual disorder treatments,\" Kingsberg said. \"Right now, there are very limited options, but I think it\'s coming.\"

SOURCES: Jan L. Shifren, M.D., associate professor, obstetrics, gynecology and reproductive biology, Harvard Medical School, and director, Vincent Menopause Program, Massachusetts General Hospital, Boston; Sheryl Kingsberg, Ph.D., chief, Division of Behavioral Medicine, MacDonald Women\'s Hospital, University Hospitals Case Medical Center, Cleveland; November 2008, Obstetrics & Gynecology

uh, guys? use the other head please...

Most Single Adults Not Using Condoms
By Steven Reinberg
HealthDay Reporter

TUESDAY, Nov. 11 (HealthDay News) -- Six out of every 10 middle-aged Britons do not use a condom during a first-time sexual encounter, a new study shows.

Those numbers might be similar for Americans, one expert said. \"Data in the U.S. are likely comparable and, given prevailing policies with regard to contraception, may be worse,\" said Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine in New Haven, Conn.
Latest Infectious Disease News

In fact, U.S. rates of all STDs, including HIV, have been increasing with an estimated 19 million new cases each year and more than 1 million people living with HIV. Almost half of the new cases of STDs are among people 15 to 24, according to the U.S. Centers for Disease Control and Prevention.

But older adults are at risk, too. \"Often it\'s assumed that sexually transmitted infections are just increasing among young people, but U.K. surveillance data shows that sexually transmitted infection diagnosis rates are on the increase among all age groups in the U.K.,\" said Catherine Mercer, the study\'s lead researcher and a lecturer at the Centre for Sexual Health & HIV Research at University College London.

Most Britons engaging in unprotected sex are in their 30s and 40s and in relationships where there is an age difference of five or more years, according to the report, which was published in the Nov. 12 online edition of the International Journal of Epidemiology.

\"Low rates of condom use among those starting partnerships in their 30s and 40s means that they too are at great risk of sexual infections,\" Mercer said.

For the study, Mercer\'s group collected data on more than 11,000 men and women who participated in the second British National Survey of Sexual Attitudes and Lifestyles. The survey included questions on recent partnerships, condom use and how soon after meeting they had sex.

Among all the people surveyed, almost 9,600 reported having heterosexual sexual partners in the past 12 months. More men (39.1%) than women (20%) said that these relationships were \"not regular,\" the researchers reported.

More women (55.2%) than men (38.9%) said their partnerships were marriages, or involved living together with the partner. Men reported having sex sooner after a first date than women. One in five men said they had sex within 24 hours after meeting their partner compared with one in 10 women.

Over all age groups, condoms were used by 55.3% of the partners during their first sexual encounter. However, the rate of condom use declined with advancing age. For example, among 16- to 19-year-olds, 68% of males and 67.4% of females used a condom during a first sexual encounter, while among 35- to 44-year-olds only 38.1% of men and 28.8% of women used a condom.

In addition, in relationships where there was an age difference of five years or more, 60.8% were unlikely to use a condom during a first sexual encounter, compared with 44.1% of partners who were closer in age.

According to Mercer, rates of STDs are increasing in the U.K. In fact, the Health Protection Agency found a 6% increase in the number of new STDs in 2007 compared with 2006.

Additional research found that in one area of England, the rate of STDs more than doubled between 1996 and 2003.

\"Everyone starting a new sexual relationship, regardless of age, should use condoms and continue to do so, until they and their partner have both been tested for sexually transmitted infections,\" Mercer said.

People ignore condoms at their peril, Katz added.

\"Consistent use of condoms is the most reliable way of preventing HIV transmission next to abstinence, and is effective in preventing other transmissible diseases and unintended pregnancy as well,\" Katz said.

The lack of condom use by mature adults in the British study is noteworthy and disturbing, Katz said. \"These are likely people who know about condoms and can get them. There is clearly a need to better educate men and women about the hazards of unprotected sex, and the advantages of condom use. Easy access to condoms should be a priority as well,\" he said.

SOURCES: Catherine Mercer, Ph.D., lecturer, Centre for Sexual Health & HIV Research, University College London, U.K.; David L. Katz, M.D., M.P.H., director, Prevention Research Center, Yale University Medical School, New Haven, Conn.; Nov. 12, 2008, online edition, International Journal of Epidemiology

Coconut Oil May Help Fight Childhood Pneumonia

http://www.medicinenet.com

Coconut Oil May Help Fight Childhood Pneumonia
By Serena Gordon
HealthDay Reporter

THURSDAY, Oct. 30 (HealthDay News) -- Virgin coconut oil, added to antibiotic therapy, may help relieve the symptoms of community-acquired pneumonia in kids faster than antibiotic therapy alone, a new study finds.
Latest Infectious Disease News

Children who received coconut oil therapy along with antibiotics had fewer crackles (a wheezing sound in the lungs), a shorter time with an elevated respiratory rate and fever, better oxygen saturation in the blood, and shorter hospital stays, according to the study.

\"Earlier normalization of respiratory rate and resolution of crackles could also mean possible earlier discharge,\" said the study\'s lead author, Dr. Gilda Sapphire Erguiza, a pediatric pulmonologist at the Philippine Children\'s Medical Center in Quezon City.

The study\'s findings were due to be presented Wednesday at the American College of Chest Physicians meeting in Philadelphia.

Community-acquired pneumonia is an infection of the lungs that is contracted outside a hospital setting. It is a serious infection in children and affects as many as 34 to 40 youngsters per 1,000 children in Europe and North America, according to the American Academy of Family Physicians (AAFP). Lower respiratory infections are one of the leading causes of childhood mortality in developing countries, according to the AAFP.

The current study included 40 children between the ages of 3 months and 5 years old. All had community-acquired pneumonia and were being treated intravenously with the antibiotic ampicillin.

Half of the group was randomized to also receive oral virgin coconut oil in a daily dose of 2 milliliters per every kilogram of weight. The oil was given for three days in a row.

The researchers found that the respiratory rate normalized in 32.6 hours for the virgin coconut oil group versus 48.2 hours for the control group, according to the study. After three days, patients in the control group were more likely to still have crackles than those in the coconut oil group -- 60 percent of the controls still had crackles compared to 25 percent of the coconut oil group.

Those in the coconut oil group also had fevers for a shorter time, had normal oxygen saturation faster, and had shorter hospital stays, but Erguiza said these findings did not reach statistical significance.

How might the coconut oil work to ease pneumonia? Erguiza hypothesized that it may boost ampicillin\'s effectiveness because it contains lauric acid, which is known to have antimicrobial properties, she said.

One expert said the findings aren\'t definitive, however.

\"This is a very interesting but small study. The jury\'s still out as to whether there\'s a real benefit here,\" said Dr. Daniel Rauch, director of the pediatric hospitalist program at New York University Langone Medical Center.

Rauch said he wouldn\'t discourage a parent from trying this treatment, as long as they were still using antibiotics, but he said it\'s important that children aren\'t forced to take virgin coconut oil, or any other oil for that matter. The concern, he said, is that if a child is forced to ingest something like coconut oil, and doesn\'t really don\'t want to, he or she may end up choking on it and aspirating the oil into the lungs, which is very dangerous.

In an effort to prevent some pneumonias from occurring in the first place, the Pneumococcal Awareness Council of Experts initiated a \"Global Call to Action\" on Oct. 24 to urge greater access to the pneumococcal vaccine in poor countries. According to the U.S. Centers for Disease Control and Prevention\'s journal, Morbidity and Mortality Weekly Report, the pneumococcal vaccine has been introduced in 26 countries worldwide, though none are low-income countries.

SOURCES: Gilda Sapphire Erguiza, M.D., pediatric pulmonologist, Philippine Children\'s Medical Center, Quezon City, Philippines; Daniel Rauch, M.D., director, pediatric hospitalist program, New York University Langone Medical Center, and assistant professor of pediatrics, New York University School of Medicine, New York City; Oct. 29, 2008, presentation, American College of Chest Physician\'s annual meeting, Philadelphia; Oct. 23, 2008, Morbidity and Mortality Weekly Report

just one more reason to LOVE hot flashes

http://www.medicinenet.com

WEDNESDAY, Oct. 29 (HealthDay News) -- Hot flashes, night sweats and joint symptoms in breast cancer patients getting endocrine treatment are signs of estrogen depletion or blockage and may point to successful treatment, British researchers report.
They compared women who reported these symptoms and those who didn\'t mention such symptoms at their first follow-up visit during a trial assessing tamoxifen or anastrozole for adjuvant therapy of postmenopausal breast cancer.

The 37.5% of women who reported hot flashes and night sweats at the three-month follow-up visit had a lower breast cancer recurrence rate after nine years (18%) than women who didn\'t report new vasomotor symptoms (23%). The 31.4% of women who reported new joint symptoms at the follow-up visit had a 14% rate of cancer recurrence, compared to 23% for those who didn\'t report new joint symptoms.

The differences in cancer recurrence rates were seen with both tamoxifen and anastrozole. Overall, patients with and without these symptoms who received anastrozole had lower recurrence rates than those who received tamoxifen.

The study was published online and was expected to be in the December print issue of The Lancet Oncology.

\"The appearance of new vasomotor symptoms or joint symptoms within the first three months is a useful biomarker, suggesting a greater response to endocrine treatment, compared with women without these symptoms,\" wrote Professor Jack Cuzick, Cancer Research U.K. and Queen Mary School of Medicine and Dentistry, London, and colleagues.

\"Awareness of the relation between early treatment-emergent symptoms and beneficial response to therapy might be useful when reassuring patients who present with them, and might help to improve long-term treatment adherence when symptoms cannot be alleviated,\" Cuzick said in a news release from the journal.

-- Robert Preidt

SOURCE: The Lancet Oncology, news release, Oct. 30, 2008

Wednesday, November 12, 2008

daring darwin

Source: http://www.medicinenet.com

Car Surfing Deadly, Even at Slow Speeds

Car-Surfing Injuries Killed At Least 58 People From 1990 to 2008, Says CDC

By Miranda Hitti
WebMD Health News

Reviewed By Louise Chang, MD

Oct. 16, 2008 -- At least 58 people in the U.S., mostly teenage boys, died from injuries suffered while "car surfing" over the last 18 years, the CDC reports.

The CDC defines car surfing as a "thrill-seeking activity that involves riding on the exterior of a moving motor vehicle while it's being driven by someone else."

The CDC checked U.S. newspaper records for reports of car-surfing deaths and injuries from 1990 to 2008 and found 58 reports of car-surfing deaths and 41 reports of nonfatal car-surfing injuries. Boys aged 15-19 accounted for most of the cases; head injuries were the leading cause of death.

In 52% of the fatal cases, the vehicle was moving at less than 30 miles per hour when the car surfer died.

In one case, a 14-year-old boy had jumped onto the hood of a friend's car as it pulled out of a driveway. The car was moving at 5 miles per hour when the car hit a bump in the driveway; the boy hit his head and died.

"Parents and teens should be aware of the potentially lethal consequences of car surfing, which can occur even at low vehicle speeds, sometimes resulting from unanticipated movements of the vehicle, such as swerving or braking," states the CDC's Morbidity and Mortality Weekly Report.

SOURCES: CDC, Morbidity and Mortality Weekly Report, Oct. 17, 2008; vol 57: pp 1121-1124.

love is a syndrome

Source: http://www.medicinenet.com

Brain Chemical Could Spur Lovesickness
By E.J. Mundell
HealthDay Reporter

WEDNESDAY, Oct. 15 (HealthDay News) -- Pity the lovelorn prairie vole. A new study finds that when this monogamous rodent is separated from a mate, its brain starts a process that ends in lovesickness.
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The same mechanism might drive the feelings humans get when parted from a longtime mate, scientists say.

And it could also keep couples together -- even when it\'s not good for them.

\"We all know of people who are in a long-term relationship where you can\'t imagine why they are together. It may be that we are getting glimpses of real brain mechanisms that are causing that,\" said study senior author Larry Young, a psychiatry professor at Emory University\'s Center for Behavioral Neuroscience, in Atlanta.

He and his colleagues published their findings Oct. 15 in the journal Neuropsychopharmacology.

It\'s not a stretch to compare the love life of the prairie vole to that of humans, say scientists who study the neuroscience of human coupling. The female vole lives less than two years and gives birth once every 21 days, but she spends her entire life with the same male. This kind of monogamy is rare in the animal kingdom, Young added.

\"But in some species, there is something else that happens -- a bond forms between the two that can last one season or multiple seasons,\" he said. \"It\'s not just about sex, it\'s about the relationship between the two.\"

So, the prairie vole has long been a relied-upon animal model for human coupling, which tends toward monogamy. In September, for example, researchers in Sweden announced they had found a \"bonding gene\" that seemed to encourage men to stay faithful. That work stemmed from previous studies conducted with male prairie voles.

In this latest work, Young and his group examined the brains of a variety of adult male voles. Some of the voles had lifelong female partners, while other hadn\'t had time to form such bonds and were best acquainted with brother or sister voles.

All of the voles were subjected to brief stress tests, such as a swimming challenge, or being placed in a maze.

\"The ones who were [still] with a partner, or had just been separated from a sibling so they never formed a romantic bond in the first place, actively avoided the aversive or stressful situation,\" Young noted.

But what about male voles who had been recently separated from a longtime female partner?

These voles \"basically were passive -- they gave up,\" Young said. \"I would be hesitant to say that these animals were depressed, but their behavior is reminiscent of what you would see in a depressed person.\"

Examination of the brains of the lovesick voles revealed heightened activity of a chemical messenger called corticotropin releasing factor (CRF) in an area of the hypothalamus, a center for emotions in the brain.

When the researchers administered a drug that blocked CRF activity, voles who\'d been separated from their mate began to perform just as vigorously in the stress tests as all the other voles tested. It seemed the drug \"switched off\" the mechanism -- and their lovesickness, as well.

Young\'s team said it\'s important to note that CRF activity kicked in only when the vole was separated from a longtime female partner, not a sibling companion.

That suggests a neurological mechanism that pushes monogamous males and females back together.

\"Separating, you experience an aversive reaction. And you are driven to go back to the partner to alleviate that,\" Young said. \"Maybe that plays an important role in maintaining relationships.\"

While the study is aimed at better understanding how the brain reacts to partner loss, the notion of a pharmaceutical fix for lovesickness isn\'t out of the question, experts said.

Drugs that suppress CRF \"in some studies have been shown to function as antidepressants,\" noted Hasse Walum, a researcher at Sweden\'s Karolinska Institute who co-authored the bonding gene study.

According to Walum, it would be interesting now to see if anti-CRF drugs \"would be more effective in reducing depression induced by partner loss than they would be helping patients suffering from depression caused by other factors.\"

He also noted that humans vary widely in how severely they react to the loss of a longtime romantic partner, perhaps because their genes govern CRF activity differently.

Another expert believes that lovesickness can lead to very real illness, so it\'s worth investigating.

\"When it becomes detrimental to your functioning in life and health, that\'s when it\'s important to understand this and to find potential treatments,\" said Paul Sanberg, director of the Center of Excellence for Aging and Brain Repair at the University of South Florida, Tampa.

But the day when humans can take a pill to help forget a love affair gone bad is still far off, Young cautioned.

\"I don\'t want to say that this is leading directly to any kind of treatment,\" he added. \"What this will lead to is, perhaps, some investigations in humans to find if this system is involved and could it possibly be targeted, if we need to.\"

Souped-up immune cells catch even disguised HIV

Souped-up immune cells catch even disguised HIV
Sun Nov 9, 2008 5:07pm EST

By Maggie Fox, Health and Science Editor

WASHINGTON (Reuters) - Genetically engineered immune cells can spot the AIDS virus even when it tries to disguise itself, offering a potential new way to treat the incurable infection, researchers reported on Sunday.

The killer T-cells, dubbed \"assassin\" cells, were able to recognize other cells infected by HIV and slow the spread of the virus in lab dishes.

If the approach works in people, it might provide a new route of treating infection with the deadly human immunodeficiency virus, the researchers in the United States and Britain said.

\"Billions of these anti-HIV warriors can be generated in two weeks,\" said Angel Varela-Rohena of the University of Pennsylvania, who helped lead the study.

In a second, unrelated report, researchers testing Dutch biotechnology firm Crucell NV\'s experimental AIDS vaccine said it prevented infection in six monkeys.

The animals were infected with a monkey version of HIV called SIV, and the vaccine used a virus that is dangerous to use in humans, so it is not ready for human tests.

But, writing in the journal Nature, Dr. Dan Barouch of Beth Israel Deaconess Medical Center and Harvard Medical School in Boston and colleagues said it shows there is still hope for developing a vaccine against AIDS.

The AIDS virus, which infects 33 million people globally, is especially hard to fight. Like all viruses, it hijacks cells in its victims, forcing them to become little viral factories and make more virus.

ESCAPE AND EVADE

HIV is even more insidious, attacking immune system cells called CD4 T cells, which help mount a defense. It can also disguise itself to escape CD8 killer cells, also known as cytotoxic T lymphocytes or CTLs.

\"CTLs are crucial for the control of HIV infection. Unfortunately, HIV has an arsenal of mutational and nonmutational strategies that aid it in escaping from the CTL response mounted against it by its host,\" the researchers wrote in their report, published in the journal Nature Medicine.

One good defense allows HIV to hide a protein called HLA-I-associated antigen.

Varela-Rohena and colleagues took T-cells from an HIV patient and created a genetically engineered version that recognizes this deception.

\"It is possible to improve on nature when it comes to preventing HIV CTL escape,\" they wrote.

Not only could the engineered T-cells see HIV strains that had escaped detection by natural T-cells, \"but the engineered T cells responded in a much more vigorous fashion so that far fewer T-cells were required to control infection,\" Penn\'s James Riley, who also worked on the study, said in a statement.

\"In the face of our engineered assassin cells, the virus will either die or be forced to change its disguises again, weakening itself along the way,\" added Andy Sewell of Britain\'s Cardiff University.

Perhaps having to mutate will weaken the virus, the researchers said.

They plan to test the T-cell treatment in HIV patients next year.

\"We have managed to engineer a receptor that is able to detect HIV\'s key fingerprints and is able to clear HIV infection in the laboratory,\" said Bent Jakobsen, chief scientific officer at Adaptimmune Ltd, a British company launched in July that owns the rights to the technology. \"If we can translate those results in the clinic, we could at last have a very powerful therapy on our hands.\"

the upside of migraines

Migraines cut breast cancer risk 30 percent: study | Science | Reuters

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i knew i misplaced this


National Geographic News: NATIONALGEOGRAPHIC.COM/NEWS


Portal to Maya "Hell" Found in Mexico?
Alexis Okeowo in México City
for National Geographic News
Updated with video November 10, 2008

A labyrinth filled with stone temples and pyramids in 14 caves—some underwater—have been uncovered on Mexico's Yucatán Peninsula, archaeologists announced recently.




The discovery has experts wondering whether Maya legend inspired the construction of the underground complex—or vice versa.

According to Maya myth, the souls of the dead had to follow a dog with night vision on a horrific and watery path and endure myriad challenges before they could rest in the afterlife.

In one of the recently found caves, researchers discovered a nearly 300-foot (90-meter) concrete road that ends at a column standing in front of a body of water.

"We have this pattern now of finding temples close to the water—or under the water, in this most recent case," said Guillermo de Anda, lead investigator at the research sites.

"These were probably made as part of a very elaborate ritual," de Anda told National Geographic News in August. "Everything is related to death, life, and human sacrifice."

Stretching south from southern Mexico, through Guatemala, and into northern Belize, the Maya culture had its heyday from about A.D. 250 to 900, when the civilization mysteriously collapsed.

(Read about the watery graves of the Maya in National Geographic magazine.)

Myth and Reality

Archaeologists excavating the temples and pyramids in the village of Tahtzibichen, in Mérida, the capital of Yucatán state, said the oldest item they found was a 1,900-year-old vessel. Other uncovered earthenware and sculptures dated to A.D. 750 to 850.

"There are stones, huge columns, and sculptures of priests in the caves," said de Anda, whose team has been working on the Yucatán Peninsula for six months.

"There are also human remains and ceramics," he said.

Researchers said the ancient legend—described in part in the sacred book Popul Vuh—tells of a tortuous journey through oozing blood, bats, and spiders, that souls had to make in order to reach Xibalba, the underworld.

"Caves are natural portals to other realms, which could have inspired the Mayan myth. They are related to darkness, to fright, and to monsters," de Anda said, adding that this does not contradict the theory that the myth inspired the temples.

William Saturno, a Maya expert at Boston University, believes the maze of temples was built after the story.

"I'm sure the myths came first, and the caves reaffirmed the broad time-and-space myths of the Mayans," he said.

Underworld Entrances

Saturno said the discovery of the temples underwater indicates the significant effort the Maya put into creating these portals.

In addition to plunging deep into the forest to reach the cave openings, Maya builders would have had to hold their breath and dive underwater to build some of the shrines and pyramids.

Other Maya underworld entrances have been discovered in jungles and aboveground caves in northern Guatemala Belize.

"They believed in a reality with many layers," Saturno said of the Maya. "The portal between life and where the dead go was important to them."

© 1996-2008 National Geographic Society. All rights reserved.

the puppetmaster's strings

Unknown "Structures" Tugging at Universe, Study Says
John Roach
for National Geographic News
November 5, 2008

Something may be out there. Way out there.

On the outskirts of creation, unknown, unseen "structures" are tugging on our universe like cosmic magnets, a controversial new study says.

Everything in the known universe is said to be racing toward the massive clumps of matter at more than 2 million miles (3.2 million kilometers) an hour—a movement the researchers have dubbed dark flow.

The presence of the extra-universal matter suggests that our universe is part of something bigger—a multiverse—and that whatever is out there is very different from the universe we know, according to study leader Alexander Kashlinsky, an astrophysicist at NASA's Goddard Space Flight Center in Maryland.

The theory could rewrite the laws of physics. Current models say the known, or visible, universe—which extends as far as light could have traveled since the big bang—is essentially the same as the rest of space-time (the three dimensions of space plus time).

Picturing Dark Flow

Dark flow was named in a nod to dark energy and dark matter—two other unexplained astrophysical phenomena.

The newfound flow cannot be explained by, and is not directly related to, the expansion of the universe, though the researchers believe the two types of movement are happening at the same time.

In an attempt to simplify the mind-bending concept, Kashlinsky says to picture yourself floating in the middle of a vast ocean. As far as the eye can see, the ocean is smooth and the same in every direction, just as most astronomers believe the universe is. You would think that beyond the horizon, therefore, nothing is different.

"But then you discover a faint but coherent flow in your ocean," Kashlinsky said. "You would deduce that the entire cosmos is not exactly like what you can see within your own horizon."

There must be an out-of-sight mountain river or ravine pushing or pulling the water. Or in the cosmological case, Kashlinsky speculates that "this motion is caused by structures well beyond the current cosmological horizon, which is more than 14 billion light-years away."

"We Found a Great Surprise"

The study team didn't set out to explode physics as we know it.

They simply wanted to confirm the longstanding notion that the farther away galaxies are, the slower their motion should appear.

That movement is detectable in data from the Wilkinson Microwave Anisotropy Probe (WMAP), which NASA says "reveals conditions as they existed in the early universe by measuring the properties of the cosmic microwave background radiation over the full sky"—radiation thought to have been released about 380,000 years after the birth of the universe.

Hot gas in galaxy clusters warms the microwave background radiation, and "a very tiny component of this temperature fluctuation also contains in itself information about cluster velocity," Kashlinsky said.

If a cluster were moving faster or slower than the universe's background radiation, you'd expect to see the background heated slightly in that region of the universe—the result of a sort of electron-scattering "friction" between the cluster's hot gas and particles in the background radiation.

Because these fluctuations are so faint, the team studied more than 700 galaxy clusters.

The researchers had expected to find that, the farther away clusters are, the slower they appear to be moving.

Instead, Kashlinsky said, "We found a great surprise."

The clusters were all moving at the same speed—nearly 2 million miles (3.2 million kilometers) an hour —and in a single direction.

Though this dark flow was detected only in galaxy clusters, it should apply to every structure in the known universe, Kashlinsky said.

Explaining the Unexplainable

To explain the unexplainable flow, the team turned to the longstanding theory that rapid inflation just after the big bang had pushed chunks of matter beyond the known universe.

The extra-universal matter's extreme mass means it "could still pull—tug on—the matter in our universe, causing this flow of galaxies across our observable horizon," said Kashlinsky, whose team's study appeared in the October 20 issue of the Astrophysical Journal Letters.

"Strong Doubts"

Not everyone is ready to rewrite physics just yet.

Astrophysicist Hume Feldman of the University of Kansas has detected a similar, but weaker, flow.

He said the Kashlinsky team's study is "very interesting, very intriguing, [but] a lot more work needs to be done.

"It's suggestive that something's going on, but what exactly is going on? It basically tells us to investigate," he said.

David Spergel, an astrophysicist at Princeton University, echoed the sentiment.

"Until these results are reanalyzed by another group, I have strong doubts about the validity of the conclusions of this paper," he wrote in an email.

He added that, if the result does hold up, "it would have an important implication for our understanding of cosmology."

Study leader Kashlinsky agrees many questions remain unanswered. For starters: What exactly are these things that are apparently tugging our universe?

"They could be anything. As bizarre as you could imagine—some warped space-time," Kashlinsky said.

"Or maybe something dull."

why eating males pays off


Why eating males pays off, for spiders
Tue Oct 21, 2008 8:19pm EDT


WASHINGTON (Reuters) - Female spiders who eat would-be suitors produce more babies, and those babies are stronger and bigger, than spiders who stick to more mundane fare, researchers reported on Tuesday.

And the merciless mother spiders waited until they had mated with another -- ensuring they would hatch spiderlings -- before consuming their new beaux, the researchers found.

They said their study is the first "natural" experiment to prove correct the old folklore about spiders, and said it also shows why such behavior might be beneficial.

"Now we know that, at least in one species, sexual cannibalism benefiting females occurs in nature," Dr. Jordi Moya-Larano of the Estacion Experimental de Zonas Aridas in Spain, who led the study, said in a statement.

The Mediterranean tarantulas in the study did not eat their mates, but instead ate males before courtship -- and usually after the females had already mated with another male, the researchers found.

Some other studies have suggested that males may sacrifice themselves for the sake of their offspring, but this study showed that, at least in this species of spider, the males are purely unlucky victims and only the babies benefit.

Some studies had also suggested that studying spiders in the lab produced skewed results, perhaps because the creatures were stressed or perhaps because they could not obtain all their needed prey or nutrients.

So the researchers set up a field experiment in which they watched the spiders, sometimes snatching the males from the jaws of females before they were devoured.

"At natural rates of encounter with males, approximately a third of L. tarantula females cannibalized the male," they wrote in their report, published in the Public Library of Science journal PLoS ONE.

"The rate of sexual cannibalism increased with male availability, and females were more likely to kill and consume an approaching male if they had previously mated with another male," they added.

"We show that females benefit from feeding on a male by breeding earlier, producing 30 percent more offspring per egg sac, and producing progeny of higher body condition. Offspring of sexually cannibalistic females dispersed earlier and were larger later in the season than spiderlings of non-cannibalistic females."

One theory had also held that females who ate males were simply more aggressive and perhaps better hunters -- but when the males were saved just in time, those females did not produce superior broods, suggesting that the male meals were an important source of nutrition.

The study can be found at: here