Aug 28, 2010
TWO of the darkest things in the universe may be making light - or at least, radiation. When jets spat out by a supermassive black hole at the centre of a galaxy collide with dark matter, they could produce gamma rays detectable from Earth - possible evidence of the elusive dark stuff.
Jets of particles are propelled away from black holes at near the speed of light. Akin to a cosmic belch, they are thought to be connected with matter falling into the black hole. Stefano Profumo of the University of California, Santa Cruz, and his colleagues calculated how electrons in one of these jets would interact with any surrounding dark matter.
They looked specifically at the types of dark matter particles predicted by two major theories: one is supersymmetry, which proposes that each ordinary particle has a superpartner, and the other assumes that the universe is hiding a fourth spatial dimension.
They found that rather than simply ricocheting off one another, some of the electrons and dark matter particles could fuse together, transforming into a single, supersymmetric or extra-dimensional version of the electron. This particle would be heavy, and much of the electron's kinetic energy would be dumped into making the new particle. As a result, the particle would be almost standing still.
If the particle were then to decay into an electron and a ground-state dark matter particle, the electron would release gamma rays. Unlike a particle travelling fast, like those in the jets, the slow-moving particle would emit rays that could travel in any direction. This could potentially make them easier to distinguish from the flood of photons in the jet, says collaborator Mikhail Gorshteyn of Indiana University in Bloomington.
Read more at New Scientist
Scientists have discovered the Old World’s smallest species of frog living inside pitcher plants in the jungles of Southeast Asia’s Borneo.
The micro frogs, named Microhyla nepenthicola, grow to only 0.4 to 0.5 inches long — about the size of a pea. It was discovered living along the edge of a road in Kubah National Park in Borneo by a team of scientists searching for the world’s lost amphibians, species considered to be extinct that may still have remnant populations.
“I saw some specimens in museum collections that are over 100 years old,” biologist Indraneil Das, one of frog discovers, said in a press release. “Scientists presumably thought they were juveniles of other species, but it turns out they are adults of this newly-discovered micro species.”Read more at Wired
Aug 27, 2010
“The substance resembles powdered sugar and is expected to make a big commercial splash. Each particle of dry water contains a water droplet surrounded by a sandy silica coating. In fact, 95% of dry water is “wet” water. One of its key properties is a powerful ability to absorb gases.
Scientists believe dry water could be used to combat global warming by soaking up and trapping the greenhouse gas carbon dioxide. Tests show that it is more than three times better at absorbing carbon dioxide as ordinary water. Dry water may also prove useful for storing methane and expanding the energy source potential of the natural gas.
Dr Ben Carter, from the University of Liverpool, presented his research on dry water at the 240th National Meeting of the American Chemical Society in Boston. He said: “There’s nothing else quite like it. Hopefully, we may see dry water making waves in the future.”
Another application demonstrated by Dr Carter’s team was using dry water as a catalyst to speed up reactions between hydrogen and maleic acid. This produces succinic acid, a key raw material widely used to make drugs, food ingredients, and consumer products.
Usually hydrogen and maleic acid have to be stirred together to make succinic acid. But this is not necessary when using dry water particles containing maleic acid, making the process greener and more energy efficient.
“If you can remove the need to stir your reactions, then potentially you’re making considerable energy savings,” said Dr Carter.
The technology could be adapted to create “dry” powder emulsions, mixtures of two or more unblendable liquids such as oil and water, the researchers believe. Dry emulsions could make it safer and easier to store and transport potentially harmful liquids.”Read more at Yahoo News
Ötzi the Iceman, the 5,300-year-old mummy found in the Italian Alps, may have been ceremonially buried, according to a study which mapped the items found near the frozen corpse.
According to research published in the journal Antiquity, the melting glacier in the Ötztal Alps, where the well preserved mummy was found in 1991, was not the site of a murder, but a solemn burial ceremony.
"Our reconstruction suggests that Ötzi died at at lower altitude in early-mid spring, and was then buried up on the mountain with his goods in late summer or early autumn," Luca Bondioli of the National Museum of Prehistory and Ethnology in Rome told Discovery News.
Pollen found in the mummy's gut indicated that Ötzi died in April, while pollen within the ice suggested the corpse was deposited there in August or September. The theory would explain this mismatch.
The hypothesis is the last of a long series of speculation over the Iceman.
Prior to the discovery in 2001 of an arrowhead in the mummy's left shoulder, researchers believed Ötzi died at about age 45 from cold and hunger, or was the victim of a ritual sacrifice.
Further investigations established that the mortally wounded man froze at a high altitude with his tools and personal items, succumbing to the arrowhead that hit his left subclavian artery. He was escaping from a tribal clash, researchers theorized.
"Interestingly, such reconstruction has never been supported by the publication of a detailed map of the items found over the Iceman site," Bondioli said.
Read more at Discovery News
Aug 26, 2010
In almost 80 per cent of people treated with the experimental drug, tumours were significantly reduced in size.
Last night one British skin cancer specialist hailed the development as "very promising".
The drug, PLX4032, works by inhibiting a 'faulty' gene that constantly activates a protein which drives cell division and hence tumour growth.
Of 48 patients treated in the American and Australian study who had the faulty 'BRAF' gene, 37 saw their tumours shrink significantly.
In three cases the patients' tumours disappeared altogether.
By comparison dacarbazine, a chemotherapy drug which is often given to treat melanoma, only has a response rate of five to 15 per cent.
Just over 10,000 people are diagnosed with malignant melanoma every year in Britain. It is most dangerous form of skin cancer - which is triggered by excessive exposure to sunlight - as it has the potential to spread.
If spotted quickly enough chances of survival are good, but if left unchecked and it spreads the prognosis is often poor. Almost 2,000 die of malignant melanoma annually.
As the BRAF gene is present in between 40 and 60 per cent of patients with the disease, the new drug could help thousands.
Read more at The Telegraph
Scientists hope the breakthrough will also slash the cornea transplant waiting list which every year falls short by more than 500 in Britain alone.
The new technique involves growing human tissue or collagen in the laboratory and then shaping it using a contact lens mould.
Damaged and scarred tissue from the front of the eye is then removed and the "biosynthetic" replacement is stitched in its place.
Eventually existing cells and nerves in the eye grow over the artificial cornea incorporating it fully into the eye.
The first trials of the operation have shown that it is just as successful as live tissue transplantation and in some cases patients have had their sight fully restored.
Dr May Griffiths, of Linköping University, in Sweden, said: "We were very excited by the results.
"This study is the first to show an artificially fabricated cornea can integrate with the human eye and stimulate regeneration.
"With further research, this approach could help restore sight to millions of people who are waiting for a donated human cornea for transplantation.
"There is a shortage of donors and this could solve that problem. It can also be done at a fraction of the cost."
The cornea is a vulnerable shield or lens protecting the eye and plays a key role in creating vision.
It consists of three main layers – the endothelium, stroma and epithelium.
But many are damaged by scarring or disease causing blurring and even complete vision loss very much like a lens of a camera being scratched.
A clinical trial of 10 patients with damaged corneas whose damaged tissue was operated on and replaced with the artificial cornea, found vision improved in six of them.
After contact lens fitting their sight was comparable to conventional corneal transplantation with human donor tissue, according to the findings published in Science Translational Medicine.
Read more at The Telegraph
Aug 25, 2010
Diamond sheets filled with holes could be the key to the next generation of supercomputers.
Scientists in California have used commercially available technology to pattern large sheets of diamonds with tiny, nitrogen-filled holes. The nitrogen-vacancy diamonds, as the sheets are called by scientists, could store millions of times more information than current silicon-based systems and process that information dozens of times faster.
Exactly how diamond-based computing would be used has yet to be determined, but applications could range from designing more efficient silicon-based computers to drug development and cryptography.
Nitrogen has been in diamonds for as long as there have been diamonds; it's why some diamonds have a yellow hue. For years scientists have used these natural, nitrogen-infused diamonds to study various aspects of quantum mechanics.
"We've used well-known techniques to create atomic-size defects in otherwise perfect diamonds," said David Awschalom, a scientist at the University of California, Santa Barbara and co-author of a new article in the journal ACS Nano Letters.
A supercomputer based on quantum mechanics requires more precision than nature can provide, so scientists have searched for a way to artificially implant arrays of precisely patterned nitrogen holes inside sheets of diamond.
Scientists from the University of California, Santa Barbara, along with colleagues from the Lawrence Berkeley National Laboratory, created such an array by using an ion beam to first knock out two carbon atoms, and then replace them with one nitrogen atom. In one second, the scientists could inject about 4,000 glowing nitrogen atoms. In about one minute, the scientists had patterned several inches of flat diamond.
The scientists didn't use any overly complicated techniques to accomplish this. "You can buy it online, send it to another company for the patterning, and then explore it yourself," said Awschalom, whose students did exactly that to demonstrate the ease of the technology.
The key to a diamond-based quantum mechanical computer is an extra electron in the hole. In a traditional computer, information is encoded as either a "0" or a "1."
Read more at Discovery News
European astronomers on Tuesday said they had found a distant star orbited by at least five planets in the biggest discovery of so-called exoplanets since the first was logged 15 years ago.
The star is similar to our sun and its planetary lineup has an intriguing parallel with own solar system, although no clue has so far been found to suggest it could be a home from home, they said.
The star they studied, HD 10180, is located 127 light-years away in the southern constellation of Hydrus, the male water snake, the European Southern Observatory (ESO) said in a press release.
The planets were detected over six years using the world's most powerful spectograph, an instrument to capture and analyze light signatures, at ESO's telescope at La Silla, Chile.
The method consists of observing a star and seeing how the light that reaches Earth "wobbles" as a result of the gravitational pull of a passing planet.
The tiny fluctuation in light can then be used as a telltale to calculate the mass of the transiting planet.
The five detected planets are big, being the size of Neptune, although they orbit at a far closer range than our own gas giant, with a "year" ranging from between six and 600 days.
Read more at Discovery News
The child had been washing clothes and bathing at a river with friends and was returning home when she was grabbed by a man wearing a balaclava.
As her friends looked on, the man shot her in the back before dragging her away. Her headless body was found upriver a short time later.
Earlier this year, another 11-year-old albino child was killed close to the same spot in Swaziland and her hand was removed.
Police believe both children may have been targeted because of a belief by witch doctors that the blood and body parts of albinos - who lack pigment in their eyes, hair and skin - can bring good luck and fortune when used in potions.
Their value for black magic practitioners sees them often fall prey to human traffickers, one of whom was jailed for 17 years in Tanzania this week for abducting and attempting to sell a live albino man.
Read more at The Telegraph
Aug 24, 2010
Researchers have found that people and organisations that disastrously miss their goals perform much better in the long run.
That is because they gain more knowledge from their failures than their successes and the lessons are more likely to stay with them.
Professor Vinit Desai, who led the study at the University of Colorado Denver Business School, said success may be sweeter but that failure was a far better teacher.
"We found that the knowledge gained from success was often fleeting while knowledge from failure stuck around for years," he said.
"But there is a tendency in organisations to ignore failure or try not to focus on it.
"Managers may fire people or turn over the entire workforce while they should be treating the failure as a learning opportunity."
He based his research on companies and organisations that launch satellites, rockets and shuttles into space – an arena where failures are high profile and hard to conceal.
The researchers said they discovered little "significant organisational learning from success".
Prof Desai compared the flights of the space shuttle Atlantis and the Challenger.
During the 2002 Atlantis flight, a piece of insulation broke off and damaged the left solid rocket booster but did not impede the mission or the programme.
Read more at The Telegraph
“Teenage online community users feel part of their online community almost as much as they feel part of their own family. An international study of the users of teenage online community Habbo reveals that users identify more strongly with the online community than with their neighbourhood or offline hobby group. The study is based on a survey with 4299 respondents from United Kingdom, Spain and Japan. All three nationalities yielded similar results.
The study was authored by Dr. Vili Lehdonvirta, a researcher at the Helsinki Institute for Information Technology HIIT (currently a visiting scholar at the University of Tokyo), and Professor Pekka Räsänen from the University of Turku, Finland. The authors point out that peer groups are important for the development of adolescents’ identity and values. The study addresses the question of whether online groups are standing in for traditional peer groups that are thought to be weakening in some developed countries. The results confirm that online groups can act as strong psychological anchoring points for their members. The authors conclude that games, social networking sites and other online hangouts should be seen as crucial contexts for today’s youths’ identification and socialisation experiences.
The results also suggest that in relatively young information societies such as Spain, online groups are more often “virtual communities” consisting of relative strangers. In mature information societies such as Japan, online groups are more likely to be a way of keeping in touch with family and friends. This may influence the experiences that youth receive from online groups in different countries.
The study, titled “How do young people identify with online and offline peer groups? A comparison between United Kingdom, Spain and Japan,” is published by the Journal of Youth Studies, the leading international scholarly journal focusing on youth research. Habbo is a popular teenage virtual world developed by Sulake Corporation. It has 15 million monthly unique visitors from over 150 countries, according to Sulake. The site is available in 11 local language versions and recently celebrated its 10th anniversary. 90 percent of Habbo users are between 13 and 18 years old.”Read more at Science Daily
Aug 23, 2010
Researchers revised the age after analysing a mineral "relic" buried deep within the meteorite, known as an inclusion, found in the Sahara desert in northwest Africa.
These minerals, from a 1.49-kilo (3.2-pound) meteorite found in the Moroccan desert in 2004, are among the oldest solid materials formed following the birth of the Sun.
Experts said dating them could provide one of the most precise estimates of the age of the formation of the solar system.
Researchers from Arizona State University used a technique that relied on forms of lead atoms called isotopes to determine the age of this particular inclusion.
They found it formed 4.5682 billion years ago, which was between 300,000 and 1.9 million years earlier than previous estimates.
This age makes the inclusion the oldest material from the solar system that has been dated so far, according to the finding published in Nature Geoscience on Sunday.
"The age of the solar system can be defined as the time of formation of the first solid grains in the nebular disc surrounding the proto-Sun," said Dr Audrey Bouvier, a space scientist from the university's Centre for Meteorite Studies, who led the study.
Read more at The Telegraph
“Astronomers have declared that the moon is shrinking after spotting wrinkles all over the lunar surface. The tell-tale contraction marks were discovered by US scientists who examined thousands of photographs of the moon’s surface taken by a Nasa orbiter.
Some of the wrinkles are several miles long and rise tens of metres above the dusty terrain. Researchers believe they arise from the moon decreasing in size by around 200 metres across its diameter. The moon’s mean diameter is generally calculated to be 2,159 miles.
The prospect of a shrinking moon is not new to planetary experts. When the moon formed it had a hot core, much like that of the Earth, which caused it first to expand and then contract as it cooled down.
The latest findings suggest the moon could still be cooling, a process that causes the surface to compress and form the wrinkle-like features, known as lobate scarps.
A team led by Thomas Watters at the Smithsonian Institution in Washington DC studied high-resolution images of the moon taken over the past year by Nasa’s latest moon probe, the Lunar Reconnaissance Orbiter. The spacecraft cameras provide the most detailed images of the moon ever taken from orbit.
Fourteen lobate scarps were identified, at sites as far apart as the lunar equator and near the poles. The features are so pristine scientists think they could be no more than a billion years old.
“Not only could they be indicating recent contraction of the moon, they may be indicating that the moon is still contracting,” said Watters. “Until now, we really had no evidence of cooling and the contraction of the moon that would go along with it. This isn’t anything to worry about. The moon may be shrinking, but not by much. It’s not going anywhere.”"Read more at The Guardian
The results are based on analyses of mitochondrial DNA. Found in the energy-producing centers of cells, mitochondrial DNA is only passed down the maternal line, and can be traced back to one woman.
However, this doesn’t mean she was the first modern woman, rather it indicates that only her descendants survive to the present day. “There is always some other female that predated mitochondrial Eve, whose DNA didn’t make it up to modernity,” said Marek Kimmel, a professor of statistics at Rice University. “So the age of the mitochondrial Eve is always less than the age of the true, first female modern human.”
Read more at LiveScience