Why do black patients with advanced kidney disease have higher levels of creatinine, a standard indicator of kidney function, than whites? Contrary to what doctors have thought, the difference may not necessarily reflect differences in muscle mass related to younger age or differences in body composition, reports a study in the July 2008 issue of the Clinical Journal of the American Society of Nephrology (CJASN).

Led by Dr Joy Hsu of University of California, San Francisco, School of Medicine, the researchers measured serum creatinine concentrations and estimated body composition in more than 3,000 dialysis patients. Doctors measure creatinine to estimate how well a patient's kidneys are functioning—a higher creatinine level is generally a sign of lower kidney function. Creatinine levels were compared for black patients versus those of other racial/ethnic groups.

Researchers at the National Institute of Standards and Technology (NIST) have combined a cryogenic sensor and a microrefrigerator on a single microchip.

They combined a transition-edge sensor (TES)(1), a superconducting thin film that identifies X-ray signatures far more precisely than any other device, with a solid-state refrigerator based on a sandwich of a normal metal, an insulator and a superconductor.

The combo chip, a square about a quarter inch on a side, achieved the first cooling of a fully functional detector (or any useful device) with a microrefrigerator. The paper also reports the greatest temperature reduction in a separate object by microrefrigerators: a temperature drop of 110 millikelvins (mK), or about a tenth of a degree Celsius.

There are many on-going themes in the large discussion of global warming and replacing fossil fuels with renewable, clean energy. One of the dominant ones is that alternative fuels such as solar are much more expensive than fossil fuels. This argument is often put forth by those entrenched in the status quo of the fossil fuel industry. The general argument is that our entire economic world will take a hit if we use solar as it is so much more expensive that oil.

There was a recent news story here at ScientificBlogging saying that it will take another ten years for solar energy to be price-competitive with fossil fuels.

Female fruit flies sometimes choose males who are aggresive, sometimes choose males who do not fight at all, and sometimes choose males for no reason science can explain, write a team of biologists, and the findings help explain the large variation in aggressiveness in most species, including humans.

So females are unpredictable, which means the fittest males don’t always get the girl. This explains why males don't evolve towards super-aggressiveness.

“If aggression makes you more likely to father children, all males should be selected to be very aggressive. Male fruit flies (like humans and other animals) show a lot of genetic variation in aggression, and we wanted to find out why,” explained study leader Brad Foley, a post-doctoral researcher at USC.

Huge star streams in the outskirts of two nearby spiral galaxies have allowed astronomers to obtain a panoramic overview of ' galactic cannibalism' similar to that involving the Sagittarius dwarf galaxy in the vicinity of the Milky Way.

The detection of these immense stellar fossils confirms the predictions of the cold dark matter model of cosmology, which proposes that present-day grand design spiral galaxies were formed from the merging of less massive stellar systems.

The first of these debris structures surrounds the galaxy NGC 5907, located 40 million light-years from Earth and formed from the destruction of one of its dwarf satellite galaxies at least four billion years ago.

The electric solar wind sail developed at the Finnish Meteorological Institute has moved rapidly from invention towards implementation. Electric sail propulsion might have a large impact on space research and moving in space in general.

The electric solar wind sail developed by Dr. Pekka Janhunen at the Finnish Meteorological Institute might revolutionise travelling in deep space. The electric sail is a Finnish invention which uses the solar wind as its thrust source and therefore needs no fuel or propellant. The solar wind is a continuous plasma stream emanating from the Sun. Changes in the properties of the solar wind cause auroral brightening and magnetic storms, among other things.

A team of researchers from Case Western Reserve University has found that gravitational radiation—widely expected to provide “smoking gun” proof for a theory of the early universe known as “inflation”— can be produced by another mechanism.

According to physics scholars, inflation theory proposes that the universe underwent a period of exponential expansion right after the big bang. A key prediction of inflation theory is the presence of a particular spectrum of “gravitational radiation”-- ripples in the fabric of space-time that are notoriously difficult to detect but believed to exist nonetheless.

“If we see a primordial gravitational wave background, we can no longer say for sure it is due to inflation,” said Lawrence Krauss, the Ambrose Swasey Professor of Physics and Astronomy at Case Western Reserve.

Using NASA, Japanese, and European X-ray satellites, a team of Japanese astronomers has discovered that our galaxy’s central black hole let loose a powerful flare three centuries ago.

The finding helps resolve a long-standing mystery: why is the Milky Way’s black hole so quiescent? The black hole, known as Sagittarius A* (pronounced "A-star"), is a certified monster, containing about 4 million times the mass of our Sun. Yet the energy radiated from its surroundings is billions of times weaker than the radiation emitted from central black holes in other galaxies.

"We have wondered why the Milky Way’s black hole appears to be a slumbering giant," says team leader Tatsuya Inui of Kyoto University in Japan. "But now we realize that the black hole was far more active in the past. Perhaps it’s just resting after a major outburst."

Matter and anti-matter are believed to have been created in equal amounts when the universe came in to existence during the Big Bang, yet in the universe today there is only matter.

The quest to understand more about the mysterious neutrino particle which is thought to be responsible for this phenomenon has taken a major step forward. The Muon Ionisation Cooling Experiment (MICE) project, an accelerator research experiment for a major component of a future Neutrino Factory, has achieved an important milestone with the successful transport of a beam of muon particles along the MICE muon beam.

Observations of atmospheric and solar neutrinos have shown that they change state (oscillate), between three forms - electron, tau and muon - during their journey across the Earth or from the Sun to the Earth. This discovery is extremely significant since oscillations can only occur if neutrinos have mass and yet the Standard Model of particle physics, on which our current understanding of how our universe was created and is held together rests, assumes that neutrinos have no mass.