Category Archives: Science

2007 Nobel Prize in Physics

Nobel Prize in Physics 2007

This year’s physics prize is awarded for the technology that is used to read data on hard disks. It is thanks to this technology that it has been possible to miniaturize hard disks so radically in recent years. Sensitive read-out heads are needed to be able to read data from the compact hard disks used in laptops and some music players, for instance.

In 1988 the Frenchman Albert Fert and the German Peter GrÃ¼nberg each independently discovered a totally new physical effect – Giant Magnetoresistance or GMR. Very weak magnetic changes give rise to major differences in electrical resistance in a GMR system. A system of this kind is the perfect tool for reading data from hard disks when information registered magnetically has to be converted to electric current. Soon researchers and engineers began work to enable use of the effect in read-out heads. In 1997 the first read-out head based on the GMR effect was launched and this soon became the standard technology. Even the most recent read-out techniques of today are further developments of GMR.

Mammoth DNA Extracted from Hair

Mammoth DNA extracted from hair reveals ancient secrets

The woolly mammoth hair had been so well preserved that it provided the most accurate DNA sequencing of the extinct animals yet achieved. One of the animals used in the study dated back 50,000 years and its hairs allowed scientists to obtain the oldest complete sequence of mitochondrial DNA.

Three mammoths had been subjected previously to DNA sequencing, two with bone fragments and the third with a sample of muscle tissue.

Results from hair assessed using the sequencing-by-synthesis (SBS) technique were more detailed than bone and muscle samples. Importantly, said researchers, the SBS extraction technique required smaller quantities of ancient material and caused less damage to the preserved specimens.

Mammoths roamed the landscape for about six million years and their disappearance about 10,000 years ago – with a handful of dwarf mammoths surviving on remote Siberian islands until little more than 2,000 years ago – has remained a mystery.

WVU Physics Team Discovers New Phenomenon

WVU physics team discovers new phenomenon in universe

West Virginia University physics professors and an undergraduate student have discovered a new astronomical phenomenon.

Duncan Lorimer and Maura McLaughlin, assistant professors in the Department of Physics in the Eberly College of Arts and Sciences, and David Narkevic, a senior physics and political science student from Philippi, detected a powerful, short-lived burst of radio waves.

The findings of their study appear in today’s edition of the online journal Science Express.

Finding Protease Inhibitors

Can’t Cut This by Kathleen M. Wong, ScienceMatters@Berkeley:

When a malaria parasite lands in your blood, one of the first things it does is whip out its scissors. As fast as it can, this protozoan snips the hemoglobin in red blood cells to get the nutrients it needs to survive. Of course, the microbe behind this deadly disease doesn’t actually deploy stainless-steel blades. Instead, it uses an array of biochemical scissors known as proteases.

Proteases are enzymes that snip proteins. They recognize certain strings of amino acids on a substrate protein, bind to this area, then break a nearby chemical bond. Proteases can destroy proteins by snipping them in half, as in malaria. They can also activate proteins by lopping off atoms covering a reactive site.

This versatility has made proteases critical to all manner of organisms, from viruses to plants to humans. Over the past 10 years, protease inhibitor drugs have become indispensable in the fight against AIDS, cardiovascular disease and diabetes. But finding protease inhibitors is no picnic. Humans manufacture tens of thousands of proteins; figuring out which of these a protease targets is extremely challenging and time consuming.
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Instead of mixing liquid chemicals and painstakingly purifying them again at each step, he attaches his precursor molecules to polystyrene beads resembling sand grains.

Publishers Continue to Fight Open Access to Science

Publishers prepare for war over open access

On one side are the advocates of open-access journals – publications that make academic papers freely available and recoup costs by charging authors to publish. The model seems increasingly successful. New open-access journals are springing up weekly and could gain support if the US acts on plans make all its publicly funded health research freely available via a government archive.

Lined up against them are the academic publishers. The idea of open-access journals is frightening for an industry whose profits are based on subscription charges.
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Dezenhall’s strategy includes linking open access with government censorship and junk science – ideas that to me seem quite bizarre and misleading. Last month, however, the AAP launched a lobby group called the Partnership for Research Integrity in Science & Medicine (PRISM), which uses many of the arguments that Dezenhall suggested.

It is sad to see journals that were founded to promote science so flawed in their thinking today. As I said last month in Science Journal Publishers Stay Stupid: “It is time for the scientific community to give up on these journals and start looking to move to work with new organizations that will encourage scientific communication and advancement (PLoS – arXiv.org – Open Access Engineering Journals) and leave those that seek to keep outdated practices to go out of business.” Organizations can’t ignore principles when choosing tactics. Tactics that might be ok in other situations, should not be acceptable to scientists publishing scientific information. When journals move to harm science to preserve their outdated business practices they deserve to lose the respect of scientists.

How Does That Happen? Science Provides the Answer

Frozen Images

In January I dropped some bricks into my pond, which is a metre deep. In March the pond froze over and an image of the bricks appeared like a hologram in the ice (see Photo – follow link above). What caused this?
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The rough surface of the bricks, particularly around the edges and corners, provides nucleation sites for dissolved gases. Gas molecules collect preferentially around the edges of the bricks, eventually producing bubbles. As these reach a critical size they break away and float straight upwards in the still water. Because there is a layer of ice on the surface, the bubbles become trapped and frozen into it. As the ice layer thickens and bubbles continue to rise from the brick, the 3D shape develops. The rate of bubbling was probably very slow, as was the rate of freezing, so the very detailed effect was able to form.

Cool science answer. Related: Sarah, aged 3, Learns About Soap – 10 Science Facts You Should Know

Scores Ill in Peru after Meteor Strike

Scores ill in Peru ‘meteor crash’

Some 600 people in Peru have required treatment after an object from space – said to be a meteorite – plummeted to Earth in a remote area, officials say. They say the object left a deep crater after crashing down over the weekend near the town of Carancas in the Andes.

People who have visited scene have been complaining of headaches, vomiting and nausea after inhaling gases. A team of scientists is on its way to the site to collect samples and verify whether it was indeed a meteorite.
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The object then hit the ground, leaving a 30m (98ft) wide and 6m (20ft) deep crater. The crater spewed what officials described as fetid, noxious gases. The gases are believed to have affected the health of about 600 people who visited the site.

Blocking Bacteria From Passing Genes to Other Bacteria

Scientists are working on many fronts to keep deadly bacteria in check

Bacteria that cause cholera and bubonic plague turn from harmless to deadly with the flip of a genetic switch. Jam the switch and you might prevent infection, said Vladimir Svetlov, a microbiology research associate at Ohio State University and one of a group of scientists who defined the structure of a protein that appears to be the key. The discovery is one of many this year to identify structures and chemicals crucial to disease. All of this work could lead to new medicines.

At the same time, germs we once fought off with antibiotics are fighting back, forcing governments and health organizations worldwide to spend billions of dollars to find new remedies.
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Redinbo is part of a team that recently discovered that two osteoporosis drugs block a key site on E. coli bacteria, preventing it from passing antibiotic resistance genes to other E. coli.

By their nature, bacteria exchange pieces of their DNA with neighboring bacteria, leading to new forms that are virulent or resistant — or both. “This is not minor evolution,” said Irina Artsimovitch, associate professor of microbiology at Ohio State. “This is a huge genome exchange.”

Very cool stuff. Related: Antibiotic resistance: How do antibiotics kill bacteria? – Disrupting the Replication of Bacteria – Antibiotics Too Often Prescribed for Sinus Woes – Attacking Bacterial Walls

Google Lunar X Prize

The Google Lunar Xprize

seeks to create a global private race to the Moon that excites and involves people around the world and, accelerates space exploration for the benefit of all humanity. The use of space has dramatically enhanced the quality of life and may ultimately lead to solutions to some of the most pressing environmental problems that we face on earth – energy independence and climate change.
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we hope to usher in an era of commercial exploration and development, in which small companies, groups of individuals and universities can build, launch and explore the Moon and beyond.

Sergey Brin: “So now, we are here today embarking upon this great adventure of having a nongovernmental, commercial organization return to the Moon and explore. And I’m very excited that Google can play a part in it.”

Scientists Discover How Our Eyes Focus When We Read

Images of how eyes focus when reading

Hidden method of reading revealed

Previously, researchers thought that, when reading, both eyes focused on the same letter of a word. But a UK team has found this is not always the case. In fact, almost 50% of the time, each of our eyes locks on to different letters simultaneously.

At the BA Festival of Science in York, the researchers also revealed that our brain can fuse two separate images to obtain a clear view of a page. Sophisticated eye-tracking equipment allowed the team to pinpoint which letter a volunteer’s eyes focused on, when reading 14-point font from one metre away.
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The team’s results demonstrated that both eyes lock on to the same letter 53% of the time; for 39% of the time they see different letters with uncrossed eyes; and for 8% of the time the eyes are crossing to focus on different letters. A follow-up experiment with the eye-tracking equipment showed that we only see one clear image when reading because our brain fuses the different images from our eyes together.