Supernovae stand out in the sky like cosmic lighthouses. Scientists at the Max Planck Institute for Astrophysics and at the National Astronomical Institute of Italy have now found a way to use these cosmic beacons to measure distances in space more accurately. The researchers have been able to show that all supernovae of a certain type explode with the same mass and the same energy - the brightness depends only on how much nickel the supernova contains. This knowledge has allowed the researchers to calibrate the brightness of supernovae with greater precision.

Johns Hopkins Kimmel Cancer Center scientists have found a set of "master switches" that keep adult blood-forming stem cells in their primitive state. Unlocking the switches' code may one day enable scientists to grow new blood cells for transplant into patients with cancer and other bone marrow disorders.

The scientists located the control switches not at the gene level, but farther down the protein production line in more recently discovered forms of ribonucleic acid, or RNA.

Temperatures are rising on Earth, which is heating up the debate over global warming and the future of our planet, but what may be needed most to combat global warming is a greater focus on adapting to our changing planet, says a team of science policy experts writing in this week's Nature magazine.

While many consider it taboo, adaptation to global climate change needs to be recognized as just as important as "mitigation," or cutting back, of greenhouse gases humans pump into Earth's atmosphere. The science policy experts, writing in the Feb.

In recent years, scientists have discovered that a family of enzymes called sirtuins can dramatically extend life in organisms as diverse as yeast, worms, and flies. They may also be able to control age-associated metabolic disorders, including obesity and type II diabetes.

Naturally occurring substances have been shown to activate sirtuins, including a constituent of red wine called resveratrol -- although an individual would need to drink about two cases of wine a day to derive a clinically effective dose of resveratrol. Still, the findings have energized a number of scientific groups and biotechnology companies, all of which are now eagerly searching for drug candidates able to boost sirtuin activity.

According to a recent paper published by MBARI geologists and their colleagues, methane gas bubbling through seafloor sediments has created hundreds of low hills on the floor of the Arctic Ocean. These enigmatic features, which can grow up to 40 meters (130 feet) tall and several hundred meters across, have puzzled scientists ever since they were first discovered in the 1940s.


This conceptual drawing (not to scale) shows Paull's hypothesis that methane gas from deep hydrate deposits could push sediment up from below the ocean bottom to create a pingo-like feature. The gray lines in the background are from a seismic profile through one of these enigmatic features. (Image: Copyright 2007 MBARI)

Cancer cells are sick, but they keep growing because they don't react to internal signals urging them to die. Now researchers at Washington University School of Medicine in St. Louis have found an efficient way to get a messenger into cancer cells that forces them to respond to death signals. And they did it using one of the most sinister pathogens around — HIV.

"HIV knows how to insert itself into many different types of cells," says senior author William G. Hawkins, M.D., assistant professor of surgery and a member of the Siteman Cancer Center at the School of Medicine and Barnes-Jewish Hospital. "A portion of the HIV protein called TAT can transport biologically active compounds into cells. TAT is small, but it can move massive molecules.

Nanotechnology is one of the ‘next big things’ in our future.  People have elevated it to a level of near worship as the way to solve, and in some cases revolutionize a number of areas of human life.  It certainly has that potential, but nanotechnology will take us into uncharted areas and we must be cognizant of both benefits and potential liabilities.  .

Physicists at JILA have demonstrated that the warmer a surface is, the stronger its subtle ability to attract nearby atoms, a finding that could affect the design of devices that rely on small-scale interactions, such as atom chips, nanomachines, and microelectromechanical systems (MEMS).


JILA scientists measured how temperature affects the Casimir-Polder force using an apparatus that holds four small squares of glass inside a vacuum chamber. A cloud of ultracold atoms in a Bose-Einstein Condensate (BEC) was held a few micrometers below one piece of glass, and the force was calculated based on the wiggling of the BEC. Warmer glass magnified the attraction between the surface and the atoms. (Credit: E.

For women older than 35, amniocentesis is usually recommended. But the Society of Obstetricians and Gynaecologists of Canada (SOGC) is now presenting a new guideline system:

All women should have access to blood tests and ultrasounds and that the results of such measures should guide the decision for more invasive screening, such as amniocentesis.

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A public photo from Flickr

Two biologists at Penn State have discovered a master regulator that controls metabolic responses to a deficiency of essential amino acids in the diet. They also discovered that this regulatory substance, an enzyme named GCN2 eIF2alpha kinase, has an unexpectedly profound impact on fat metabolism. "Some results of our experiments suggest interventions that might help treat obesity, prevent Type II diabetes and heart attacks, or ameliorate protein malnutrition," said Douglas Cavener, professor and head of the Department of Biology, who led the research along with Feifan Guo, a research assistant professor.