Category Archives: Science

Full Body 3-D CT Scan in Under a Minute

Pretty cool new gadget, though probably out of the range of most people’s budget – ‘Super’ scanner shows key detail

The new 256-slice CT machine takes large numbers of X-ray pictures, and combines them using computer technology to produce the final detailed images. It also generates images in a fraction of the time of other scanners: a full body scan takes less than a minute.
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Because the images are 3D they can be rotated and viewed from different directions – giving doctors the greatest possible help in looking for signs of abnormalities or disease.
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At present, it is only being used in one hospital: the Metro Health medical centre in Cleveland, Ohio, which has been using it for the past month.
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the first commercially viable CT scanner, which was invented by Sir Godfrey Newbold Hounsfield in Hayes, United Kingdom at the company’s laboratories and unveiled in 1972. At the same time, Allan McLeod Cormack of Tufts University independently invented a similar machine, and the two men shared the 1979 Nobel Prize in Medicine. “This is a quantum shift from the first CT scanners as it gives a lot more detail,” says Dr Keith Prowse, Chairman of the British Lung Foundation.

Gates Foundation and Rotary Pledge $200 Million to Fight Polio

Did you think polio was cured decades ago? Well in the rich world is largely has been but it has not been eradicated everywhere. Gates Foundation, Rotary pledge $200 million to fight polio:

Scientists and public health professionals have been debating whether eradication is possible. Some have argued that resources should be directed at trying to contain the disease, which would be far less costly than trying to eliminate it entirely. That idea was dismissed at today’s announcement. “Eradicating polio is an achievable goal,” said William Gates Sr., co-chairman of the Bill & Melinda Gates Foundation.

Dr. Margaret Chan, director-general of the World Health Organization, said: “We have very few opportunities to improve the world in a permanent way. And this is one.” Polio has stricken untold millions around the world. In 1952, its peak year in the U.S., it paralyzed more than 20,000 Americans. But it became a disease of the past in this country after the discovery of a preventive vaccine in the 1950s and universal immunization.
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The Gates grant comes at a critical time for the global initiative, which faces a funding shortfall of $650 million, officials said. Most of the initial $100 million will be spent on mass immunization campaigns, poliovirus surveillance activities, and community education and outreach in polio-affected countries.

In recent years, importation of the disease from affected areas into countries where the disease had been eliminated has set back eradication efforts. But last month the World Health Organization released data indicating that the last four polio-endemic countries were within reach of wiping out the disease. The health authority said significant progress had been made in India and Nigeria, which together account for 85 percent of the world’s polio cases.

Why is the Sky Blue?

Here is a a nice post explaining why we see blue when we look at the sky, Why Is The Sky Blue?:

Most of the atmospheric gases are transparent to visible light. They don’t filter the Sun’s light and make it yellow, as a yellow filter would. Besides, if colored gases made the Sun appear yellow, where does the blue come from? The part of the atmosphere that changes the Sun’s light is the molecules and tiny particles that are floating in it.

There are particles of water–tiny droplets too small to be seen as clouds. There are particles of organic material–smog or haze, condensed from volatile organic chemicals that have gotten into the air. There are particles of sulfuric acid from volcanoes and power plants. There are molecules of gases in the atmosphere.

These tiny particles, much smaller than the wavelengths of sunlight, scatter the sunlight as photons from the Sun interact with the particles. This is called Rayleigh scattering after the British physicist who described how it works. (Larger particles, like the water droplets in clouds, are closer to the wavelengths of sunlight, and they scatter it differently. This is why clouds are not blue.)

Science explained – quick overviews of scientific concepts: How Does That Happen? Science Provides the Answer – Incredible Insects – 10 Science Facts You Should Know – What Everyone Should Learn – Science Summary: Photosynthesis – String Theory in 1 page – How do antibiotics kill bacteria?

Evidence of Short DNA Segment Self Assembly

Tiny DNA Molecules Show Liquid Crystal Phases, Pointing Up New Scenario For First Life On Earth, University of Colorado:

CU-Boulder physics Professor Noel Clark said the team found that surprisingly short segments of DNA, life’s molecular carrier of genetic information, could assemble into several distinct liquid crystal phases that “self-orient” parallel to one another and stack into columns when placed in a water solution. Life is widely believed to have emerged as segments of DNA- or RNA-like molecules in a prebiotic “soup” solution of ancient organic molecules.
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Such DNA polynucleotides had previously been shown to organize into liquid crystal phases in which the chains spontaneously oriented parallel to each other, he said. Researchers understand the liquid crystal organization to be a result of DNA’s elongated molecular shape, making parallel alignment easier, much like spaghetti thrown in a box and shaken would be prone to line up in parallel, Clark said.

The CU-Boulder and University of Milan team began a series of experiments to see how short the DNA segments could be and still show liquid crystal ordering, said Clark. The team found that even a DNA segment as short as six bases, when paired with a complementary segment that together measured just two nanometers long and two nanometers in diameter, could still assemble itself into the liquid crystal phases, in spite of having almost no elongation in shape.

Structural analysis of the liquid crystal phases showed that they appeared because such short DNA duplex pairs were able to stick together “end-to-end,” forming rod-shaped aggregates that could then behave like much longer segments of DNA. The sticking was a result of small, oily patches found on the ends of the short DNA segments that help them adhere to each other in a reversible way — much like magnetic buttons — as they expelled water in between them, Clark said.
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“In essence, the liquid crystal phase condensation selects the appropriate molecular components, and with the right chemistry would evolve larger molecules tuned to stabilize the liquid crystal phase. If this is correct, the linear polymer shape of DNA itself is a vestige of formation by liquid crystal order.”

New Triceratops Ancestor

Alberta palaeontologists discover new dino genus

Scientists from the Royal Tyrrell Museum and the Canadian Museum of Nature have [discovered]… Eotriceratops xerinsularis (pronounced EE-OH-try-sair-ah-tops ZEER-in-soo-lair-iss)… The dino may be an ancestor of the well-know triceratops, and at the very least, is the group’s earliest known member; researchers say the Eotriceratops lived in southern Alberta 68 million years ago.

It is the largest type of horned dinosaur ever discovered in Alberta, and possibly the world.

According to researchers, Eotriceratops likely reached eight or nine metres from nose to tail. It had a massive skull that featured a solid frill (this alone was three metres in length), and three horns – two above each eye, and another, shorter one, perched on its nose.
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Judging by its teeth, the Eotriceratops was a plant-eater, but one that would have been able to ward off predators.

Who Should Profit from Yellowstone’s Microbes

The Gold in Yellowstone’s Microbes

Year by year, Yellowstone’s hot waters are yielding remarkable new microbial specimens with implications for medicine, agriculture and energy, as well as offering clues to the formation of earliest life on Earth and maybe even on Mars. The potential financial windfalls are enormous, as evidenced by one big jackpot.
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Yellowstone microbes (and those from a few other hot spots on the planet) may also hold great promise for bioremediation — cleaning up chemical pollution, oil slicks and smokestack emissions — as well as the means to accelerate biomass fermentation and develop drought-resistant crops. And there is more to be discovered: Probably less than one percent of Yellowstone’s microscopic life forms have been discovered and studied.
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the National Park Service signed a secretive research-sharing agreement with Diversa Corporation in 1998. Non-profit groups quickly cried “bio-piracy!” when they found out and sued the Service over the arrangement. While a federal court dismissed the case, it ordered the Park Service to address the issue… But the Park Service is still trying to come up with an acceptable, benefits-sharing agreement that might allow bio-prospecting of microbes and disclosure of findings, with a fair return to the Park from any commercial success.

Nigersaurus

photo of the Nigersaurus Jaw Bones

Structural Extremes in a Cretaceous Dinosaur

Nigersaurus taqueti shows extreme adaptations for a dinosaurian herbivore including a skull of extremely light construction, tooth batteries located at the distal end of the jaws, tooth replacement as fast as one per month, an expanded muzzle that faces directly toward the ground, and hollow presacral vertebral centra with more air sac space than bone by volume. A cranial endocast provides the first reasonably complete view of a sauropod brain including its small olfactory bulbs and cerebrum. Skeletal and dental evidence suggests that Nigersaurus was a ground-level herbivore that gathered and sliced relatively soft vegetation, the culmination of a low-browsing feeding strategy first established among diplodocoids during the Jurassic.

This discovery has received a good deal of coverage. Among other things it is great to see this paper is available to everyone who wants to view it because it is published by open access PLoS One. The Nigersaurus was discovered in what is now the Sahara Desert in Niger. When the Nigersaurus was roaming the area, 110 million years ago, the climate was a Mesozoic forest. The dinosaur had a few hundred teeth that were replaced almost monthly (a record). The bones of the head and neck were so minimal and light that the Read more about the Nigersaurus. As the author stated: “One of the stunning things about this animal is how fragile the skull is… Some of the bones are so thin you can shine a light through them.”

2nd Annual Science Blogging Conference

2nd Annual Science Blogging Conference will be held in North Carolina on January 19th (there are also pre-conference activities on the 18th). I unfortunately won’t make it but take a look and see if it is something you would enjoy. The program includes:

Open Science: how the Web is changing the way science is done, written and published with Dr.Hemai Parthasarathy
Blogging about the Social Sciences and Humanities with Martin Rundkvist and John McKay
Changing Minds through Science Communication: a panel on Framing Science with Chris Mooney , Jennifer Jacquet and Sheril Kirshenbaum

Open Laboratory 2007, an anthology of science blog posts will be published, as it was last year. Posts need to have been posted between 20 Dec 2006 and 20 Dec 2007 to be eligible. Submit your suggestions.

New Theory of Everything

Surfer dude stuns physicists with theory of everything

An impoverished surfer has drawn up a new theory of the universe, seen by some as the Holy Grail of physics, which as received rave reviews from scientists. Garrett Lisi, 39, has a doctorate but no university affiliation and spends most of the year surfing in Hawaii, where he has also been a hiking guide and bridge builder (when he slept in a jungle yurt).
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Despite this unusual career path, his proposal is remarkable because, by the arcane standards of particle physics, it does not require highly complex mathematics. Even better, it does not require more than one dimension of time and three of space, when some rival theories need ten or even more spatial dimensions and other bizarre concepts. And it may even be possible to test his theory, which predicts a host of new particles, perhaps even using the new Large Hadron Collider atom smasher that will go into action near Geneva next year.
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Although the work of 39 year old Garrett Lisi still has a way to go to convince the establishment, let alone match the achievements of Albert Einstein, the two do have one thing in common: Einstein also began his great adventure in theoretical physics while outside the mainstream scientific establishment, working as a patent officer, though failed to achieve the Holy Grail, an overarching explanation to unite all the particles and forces of the cosmos.

Now Lisi, currently in Nevada, has come up with a proposal to do this. Lee Smolin at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, Canada, describes Lisi’s work as “fabulous”. “It is one of the most compelling unification models I’ve seen in many, many years,” he says.

Actual open access paper: An Exceptionally Simple Theory of Everything by A. Garrett Lisi
Reactions: A Theoretically Simple Exception of Everything – Upon further review, surfer’s new Theory of Everything severely deficient
Related: String Theory – CERN Pressure Test Failure – Webcasts by Chemistry and Physics Nobel Laureates

The Brain is Wired to Mull Over Decisions

New studies have identified a specific neural circuit in the brains of monkeys that is activated when they postpone acting on a decision. The circuit is thought to keep potential choices brewing in memory even after a decision has already been made.

The brain may continue to consider the options even after a decision is made because that extra consideration may sometimes result in a change of mind – and a possible reward, such as a tastier meal. The researchers said that their findings could offer important insight into the function of neural circuits that drive the brain’s memory and decision-making machinery.
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the researchers conducted experiments in which they required the monkeys to delay their decision. At the same time, the researchers recorded the electrical activity of neurons in a region called the medial premotor cortex—one of the brain regions involved in decision-making and motor choice.

“To our surprise, when the monkeys held the decision for several seconds, what we saw in the activity of these brain cells in the medial premotor cortex is that they were still remembering the sensory information on which the decision was based,” said Romo. “During that time the neurons were recalling the first stimulus, recalling the second, comparing the second against the first, and even reporting in their activity the categorical decision.”