Polar bears traced to one brown bear

Mitochondrial DNA in the bones of extinct brown bears collected from Irish caves most closely resembled the DNA of modern polar bears.

All polar bears alive today are descended from a single female brown bear who most likely hailed not from Alaska – as widely presumed – but from Ireland, scientists said.

The discovery, reported online in the journal Current Biology, suggests that polar bears and various species of brown bears probably encountered each other many times over the last 100,000 years or so as climate change forced them into each others’ territory. On some occasions, those meetings produced hybrid offspring whose genetic signature lives on in polar bears today.

The findings were made by analyzing the mitochondrial DNA extracted from 242 bear lineages. Some of them were polar bears and some were brown bears. Some lived recently and others have been dead since the late Pleistocene, which ended nearly 12,000 years ago.

via Polar bears traced to one brown bear | CharlotteObserver.com & The Charlotte Observer Newspaper.

100 Mbit/s data transfer using visible light

Regular LEDs can be turned into optical WLAN with only a few additional components thanks to visible light communication (in short, VLC). The lights are then not just lighting up, they also transfer data. They send films in HD quality to your iPhone or laptop, with no loss in quality, quickly and safely.

Just imagine the following scenario: four people are comfortably ensconced in a room. Each one of them can watch a film from the Internet on his or her laptop, in HD quality. This is made possible thanks to optical WLAN. Light from the LEDs in the overhead lights serves as the transfer medium. For a long time, this was just a vision for the future. However, since scientists from the Fraunhofer Institute for Telecommunications, Heinrich Hertz Institute HHI in Berlin, Germany, have developed a new transfer technology for video data within the scope of the OMEGA project of the EU, its implementation in real life is getting markedly closer. At the end of May, the scientists were able to present the results of the project in Rennes, France. They were able to transfer data at a rate of 100 megabits per second (Mbit/s) without any losses, using LEDs in the ceiling that light up more than ten square meters (90 square feet). The receiver can be placed anywhere within this radius, which is currently the maximum range. “This means that we transferred four videos in HD quality to four different laptops at the same time,“ says Dr. Anagnostis Paraskevopoulos from the HHI.

“The fundamentals of visible light communication (VLC) were developed together with the industry partners Siemens and France Telecom Orange Labs,“ said the expert. At HHI, the team of project manager Klaus-Dieter Langer is now further developing the new technology. “For VLC the sources of light – in this case, white-light LEDs – provide lighting for the room at the same time they transfer information. With the aid of a special component, the modulator, we turn the LEDs off and on in very rapid succession and transfer the information as ones and zeros. The modulation of the light is imperceptible to the human eye. A simple photo diode on the laptop acts as a receiver. As Klaus-Dieter Langer explains, “The diode catches the light, electronics decode the information and translate it into electrical impulses, meaning the language of the computer.“ One advantage is that it takes only a few components to prepare the LEDs so that they function as transfer media. One disadvantage is that as soon as something gets between the light and the photo diode (for example, when someone holds his hand over the diode) the transfer is impaired. Laptops, Palm devices or mobile telephones are all potential end devices.

The scientists emphasize that VLC is not intended to replace regular WLAN, PowerLAN or UMTS. It is best suited as an additional option for data transfer where radio transmission networks are not desired or not possible – without needing new cables or equipment in the house. Combinations are also possible, such as optical WLAN in one direction and PowerLAN for the return channel. Films can be transferred to the PC like this and also played there, or they can be sent on to another computer. …

via Data are traveling by light – Reserch News 8/2011 – Topic 2 – Fraunhofer-Gesellschaft.

900 lb giant fungus discovered in China

The most massive fruiting body of any fungus yet documented has been discovered growing on the underside of a tree in China.

The fruiting body, which is equivalent to the mushrooms produced by other fungi species, is up to 10m long, 80cm wide and weighs half a tonne.

That shatters the record held previously by a fungus growing in Kew Gardens in the UK.

The new giant fungus is thought to be at least 20 years old.

The first example of the new giant fungus was recorded by scientists in 2008 in Fujian Province, China, by Professor Yu-Cheng Dai of the Herbarium of biology at the Chinese Academy of Sciences in Shenyang and his assistant Dr Cui.

“But the type collection was not huge,” Prof Dai told BBC Nature.

However, “we found [the] giant one in Hainan Province in 2010.”

The researchers were in the field studying wood-decaying fungi when they happened upon the specimen, which they describe in the journal Fungal Biology.

“We were not specifically looking for this fungus; we did not know the fungus can grow so huge,” he said.

“We were surprised when we found it, and we did not recognise it in the forest because it is too large.”

The fungus, F. ellipsoidea, is what mycologists call a perennial polypore – otherise known as a bracket fungus.

Being a perennial, it can live for a number of years, which may have enabled it to grow to such large size. …

Tests on the density of the fruiting body suggest the whole thing weighs 400-500kg; it is also estimated to hold some 450 million spores.

via BBC Nature – Giant fungus discovered in China.

Man who could hear his own eyeballs roll cured

Stephen Mabbutt, 57, from Charlton, near Banbury, could also hear his own heart beating.

Mr Mabbutt first experienced symptoms six years ago, when he felt a dull ache in the side of his head.

GPs treated him with nasal sprays and antibiotics, but his hearing deteriorated. Mr Mabbutt was eventually diagnosed with an unusual ear condition in which sounds inside the body are heard very loudly. The condition meant that the noise from chewing food became deafening.

His symptoms worsened to the extent where loud noises caused dizziness and his vision blurred.

Mr Mabbutt told the BBC: “When I raised my voice I could hear it reverberating in my head and the vibrations made my vision vibrate.

“Eventually I could hear my heart beating and my eyes moving in their sockets. It was really distracting.”

Mr Mabbutt was referred to Martin Burton, a surgeon from the Oxford Radcliffe Hospital who helped establish the Cochrane Ear, Nose and Throat Disorders Group. A CT scan found perforations inside the semicircular canals inside Mr Mabbutt’s ear.

He was diagnosed with superior canal dehiscence syndrome (SCDS), a rare condition discovered by American surgeon Lloyd B Minor in 1995, which is thought to only effect one in 500,000 a year in Britain.

The operation to cure the problem involved a 5cm (2in) incision behind the ear, making a channel through the bone to find the “balance organ” and using the patient’s own bone to create a seal around the defect, the BBC said.

It was carried out by Richard Irving, an expert at the Birmingham Ear Clinic.

“It’s made a big difference to my life. I feel a different person all round,” Mr Mabbutt said.

via Man who could hear his own eyeballs roll cured – Telegraph.

Ford recalls 1.2m F-series pick-up trucks

Ford is recalling 1.2 million pick-up trucks in the United States and Canada because of fears their fuel tanks could fall off and start fires.

The recall affects some versions of the F-150, F-250 and Lincoln Blackwood trucks built between 1997 and 2004 – in certain cold-weather states.

It is feared the straps holding the tanks on can be corroded by road salt.

Ford will advise owners with the affected vehicles to take them to a dealer to have the straps replaced.

The F-series has been one of America’s best-selling vehicles.

Ford said this defect has caused eight fires, and one injury.

via BBC News – Ford recalls 1.2m F-series pick-up trucks.

Still feel safer in your big truck that might drop a gas tank and catch on fire? Well, just take it in and get those gas tank straps replaced. You’ll be fine.

Physics could be behind the secrets of crop-circle artists

In this month’s edition of Physics World, Richard Taylor, director of the Materials Science Institute at the University of Oregon, takes a serious, objective look at a topic that critics might claim is beyond scientific understanding – crop circles.

As the global crop-circle phenomenon grows alongside advances in science and technology, Taylor notes how physics and the arts are coming together to produce more impressive and spectacular crop-circle patterns that still manage to maintain their mystery.

Today’s crop-circle designs are more complex than ever, with some featuring up to 2000 different shapes. Mathematical analysis has revealed the use of constructions lines, invisible to the eye, that are used to design the patterns, although exactly how crop circles are created remains an open question.

According to Taylor, physics could potentially hold the answer, with crop-circle artists possibly using the Global Positioning System (GPS) as well as lasers and microwaves to create their patterns, dispensing with the rope, planks of wood and bar stools that have traditionally been used.

Microwaves, Taylor suggests, could be used to make crop stalks fall over and cool in a horizontal position – a technique that could explain the speed and efficiency of the artists and the incredible detail that some crop circles exhibit.

Indeed, one research team claims to be able to reproduce the intricate damage inflicted on crops using a handheld magnetron, readily available from microwave ovens, and a 12 V battery.

As Taylor writes, “Crop-circle artists are not going to give up their secrets easily. This summer, unknown artists will venture into the countryside close to your homes and carry out their craft, safe in the knowledge that they are continuing the legacy of the most science-oriented art movement in history.”

Matin Durrani, Editor of Physics World, says, “It may seem odd for a physicist such as Taylor to be studying crop circles, but then he is merely trying to act like any good scientist – examining the evidence for the design and construction of crop circles without getting carried away by the side-show of UFOs, hoaxes and aliens.”

via Physics could be behind the secrets of crop-circle artists.

The Whitening of Sammy Sosa

Not sure why anyone would want to do this, but it is interesting that it can be done.

Sammy Sosa says a cosmetic cream he uses to soften his skin is the reason for his lighter skin tone.

The former Chicago Cubs slugger was photographed at the Latin Grammy awards in Las Vegas last week with a noticeably whiter face.

Sosa says he has been using the cream for a long time, and combined with bright TV lights, it made his face look whiter than it really is. Sosa says he is not trying to look like late pop star Michael Jackson and is not suffering from any skin illness.

Sosa made his remarks on the Univision Spanish network. He declined to identify the cream.

via Sammy Sosa’s Skin PHOTOS: Pictures Reveal White Pigmentation | NewstalkCleveland – WERE 1490 Cleveland’s Home for Honest News.

How could it work? According to one source, monobenzylether of hydroquinone is toxic specifically to the pigment cells.  More info, including why this could be potentially dangerous:

Sosa issued his own statement insisting that he is not a racist, and that he’s been using a cream he purchased from Europe which he plans to market soon to the general public.

“What happened was that I had been using the cream for a long time and that, combined with the bright TV lights, made my face look whiter than it really is. I don’t think I look like Michael Jackson.”

“This has caused such a controversy that even I am surprised.”

A Chicago dermatologist says he shouldn’t be.

“I see a man who has changed at least six shades of color in his skin”, said Dr. Omeed Memar.

Dr. Memar believes Sosa used a more powerful form of the chemical hydroquinone, monobenzone, which ultimately removes all skin pigmentation, including on his lips.

Looking at a recent photo of Sosa with lighter skin, Dr. Memar said, “Here you’re seeing almost like lipstick color, so this is most likely a lip tattoo, a permanent tattoo.”

Hydroquinone (monobenzylether) is usually used to treat vitiligo, the disease which Michael Jackson said produced blotchy white patches, and led him to bleach his skin to even out his skin tone.

Sosa denies having vitiligo, but Dr. Memar isn’t so sure.

I would consider that not treatment, going from black to lighter color, or depigmented white. That’s almost mutilation, said Dr. Memar.

Unless Sosa suffered some kind of skin disfiguration, Dr. Memar says hydroquinone (monobenzylether?) is both unprofessional and dangerous.

He’s subjecting himself to a potential carcinogen, said Dr. Memar. He’s setting himself up for skin cancer for the rest of his life, because of the loss of pigmentation.

Dr. Memar says Sosa probably used the cream for at least three months, and possibly several more, to achieve the degree of skin lightening we’ve seen.

But Dr. Memar also points out, his conclusions are only an educated guess and Sosa’s medical history is no one’s business but his own.

via examiner.com

Yes, I know this is a few years old, but I don’t pay much attention to sports news so I missed it in 2009.

New composite material may restore damaged soft tissue

Jennifer Elisseeff, PhD, is an assistant professor of biomedical engineering at Johns Hopkins University with an adjunct appointment in Orthopedic Surgery. Her biomaterials and tissue engineering laboratory at Johns Hopkins focuses on developing new biomaterials and minimally invasive technologies for tissue repair, stem cells, and musculoskeletal tissue engineering. – link

Biomedical engineers at Johns Hopkins have developed a new liquid material that in early experiments in rats and humans shows promise in restoring damaged soft tissue relatively safely and durably. The material, a composite of biological and synthetic molecules, is injected under the skin, then “set” using light to form a more solid structure, like using cold to set gelatin in a mold. The researchers say the product one day could be used to reconstruct soldier’s faces marred by blast injuries.

The Hopkins researchers caution that the material, described in a report in the July 27 issue of Science Translational Medicine, is “promising,” but not yet ready for widespread clinical use.

“Implanted biological materials can mimic the texture of soft tissue, but are usually broken down by the body too fast, while synthetic materials tend to be more permanent but can be rejected by the immune system and typically don’t meld well with surrounding natural tissue,” says Jennifer Elisseeff, Ph.D., Jules Stein Professor of Ophthalmology and director of the Translational Tissue Engineering Center at the Johns Hopkins University School of Medicine. “Our composite material has the best of both worlds, with the biological component enhancing compatibility with the body and the synthetic component contributing to durability.”

The researchers created their composite material from hyaluronic acid (HA), a natural component in skin of young people that confers elasticity, and polyethylene glycol (PEG), a synthetic molecule used successfully as surgical glue in operations and known not to cause severe immune reactions. The PEG can be “cross-linked”—or made to form sturdy chemical bonds between many individual molecules—using energy from light, which traps the HA molecules with it. Such cross-linking makes the implant hold its shape and not ooze away from the injection site, Elisseeff says. …

via New composite material may restore damaged soft tissue.

Today’s inspiring scientist award goes to Dr. Jennifer Elisseeff. She has an interview on Engineer Girl.  Awesome accomplishments:

“Dr. Elisseeff is now an Associate Professor of Biomedical Engineering and Orthopedic Surgery and directs the Cell and Tissue Engineering Program in the Department of Biomedical Engineering at Johns Hopkins. She serves on the Scientific Advisory Board of Bausch and Lomb and Cellular Bioengineering Inc. Dr. Elisseeff has received awards including the Carnegie Mellon Young Alumni Award, Arthritis Investigator Award from the Arthritis Foundation, Yasuda Award from the Society of Physical Regulation in Medicine and Biology, and was named by Technology Review magazine as a top innovator under 35 in 2002 and top 10 technologies to change the future. She has published over 70 articles, book chapters and patents and given over 100 national and international invited lectures.” – link

Technology review has great write up (and photo):

Jennifer Elisseeff is shining light on better ways to repair human tissue. While getting her doctorate in medical engineering from the Harvard University-MIT Division of Health Sciences and Technology, Elisseeff designed a liquid polymer that can keep cartilage cells alive. In patients, the polymer hardens into a hydrogel—a scaffold on which the cells can develop into new tissue. Normally, surgeons have to cut open a patient to insert such a polymer, and shine light on it to induce it to harden. Elisseeff wondered if she could devise a polymer that hardened under minimal light. That way, surgeons could simply inject the compound and shine a light through the skin to trigger solidification, obviating the need for surgery. Her experiments with mice and rats succeeded. Now, Advanced Tissue Sciences of La Jolla, CA, is investigating the polymer as a way to repair everything from ruined knees to facial damage. Meanwhile, Elisseeff is impregnating hydrogels with stem cells—which can mature into different human cells—to try to create a new form of cartilage replacement. “So little is known about stem cells,” she says. “It’s very exciting.” – technologyreview

Debating the safety of cell phone use

The dangers of cell phones have led to preventive policies in France, Israel, Finland, and India, and there are simple ways to minimize the health risks associated with exposure to the radiation energy they emit, according to Devra Lee Davis, PhD, MPH, President of the Environmental Health Trust, in a timely and informative interview featured in Alternative and Complementary Therapies, published by Mary Ann Liebert, Inc. The interview is available free online at http://www.liebertpub.com/alt

Drawing on published studies on the effects of cell phone use and recent global initiatives advancing cell phone safety, Dr. Davis discusses the various ways the microwave radiation given off by cell phones that are on, whether in use or not, affect the body, and offers practical recommendations for optimizing safe use. In the interview, she explores the health risks and concerns associated with cell phone use such as brain cancer, sperm motility and viability, long-term health implications for young people, and dementia in older people.

An award-winning scientist, Dr. Davis, whose most recent book, Disconnect, focuses on the little-known science underlying cell phones and health, recognizes the practical and societal value of cell phones but cautions that their use is not without health risks, calling upon industry and government to take the necessary steps to help people understand and minimize their risk. “In using phones, distance is your friend, because radiation exposure falls off dramatically the farther away from the brain or body you use your phone,” Dr. Davis noted. “If you read the fine print warnings that come with all smart phones today they are quite clear—phones should not be used next to the brain or body, or kept in the pocket,” she added.

via Debating the safety of cell phone use.