Thursday, November 30, 2006

Curiouser and Curiouser

Dark matter hides, physicists seek | SpaceRef
"'It's harder and harder to get away from the fact that there is a substance out there that's making up most of the universe that we can't see,' says Cabrera. 'The stars and galaxies themselves are like Christmas tree lights on this huge ship that's dark and neither absorbs nor emits light.'

Buried deep underground in a mineshaft in Minnesota lies Cabrera's project, called the Cryogenic Dark Matter Search II (CDMS II). University of California-Berkeley physicist Bernard Sadoulet serves as spokesperson for the effort. Fermilab's Dan Bauer is its project manager, and Dan Akerib from Case Western Reserve University is the deputy project manager. A team of 46 scientists at 13 institutions collaborates on the project"

Thursday, November 23, 2006

Laser Interferometry

Technology Review -- By Jennifer Chu
"In contrast, Feld and his colleagues have been able to image live, untreated cells by using an optical technique based on interferometry: a laser beam passed through a sample is compared with a reference beam of similar wavelength that is not passed through the cell. For example, it takes longer for light to travel through a cell than through, say, water. Researchers can measure that time delay, or phase shift, and then can map the cell and its motions on the scale of nanometers."

Finally Home from Pork Chop Hill

"NEWS RELEASES from the United States Department of Defense

November 22, 2006
Media Contact: (703) 697-5131/697-5132
Public/Industry(703) 428-0711

Soldier Missing in Action from the Korean War is Identified

The Department of Defense POW/Missing Personnel Office (DPMO) announced today that the remains of a U.S. serviceman, missing in action from the Korean War, have been identified and returned to his family for burial with full military honors.

He is Pfc. Charles H. Long, U.S. Army, of Durand, Ill. He will be buried Nov. 25 in Durand.

Representatives from the Army met with the next-of-kin to explain the recovery and identification process and to coordinate interment with military honors on behalf of the Secretary of the Army.

On March 24, 1953, Long was one of four men from L Company,3rd Battalion, 31st Infantry Regiment, 7th Infantry Division, who was declared missing in action after engaging enemy forces north of the Demilitarized Zone (DMZ) on what came to be known as Pork Chop Hill. The bodies of two of the MIAs were recovered and a third MIA was returned alive during Operation Big Switch after having been captured by Chinese Communist Forces. Long remained unaccounted-for, and was eventually declared dead on March 24, 1954.

In 1993, the Democratic People's Republic of Korea (DPRK) gave United Nations officials 33 boxes with human remains of alleged U.S. servicemen who were unaccounted-for. The DPRK recovered the remains near Komsa-ri in Kangwon Province, which was near Long's last known location. Also included in one of the boxes were Long's social security and identification cards along with identification

Among other forensic identification tools and circumstantial evidence, scientists from the Joint POW/MIA Accounting Command (JPAC)and the Armed Forces DNA Identification Laboratory also used mitochondrial DNA and dental comparisons in the identification of the remains.

For additional information on the Defense Department's mission to account for missing Americans, visit the DPMO Web site at or call (703) 699-1169."

Tuesday, November 21, 2006

"Supercomputer study shows Milky Way's [posited] halo of dark matter"

Supercomputer study shows Milky Way's halo of dark matter in unprecedented | SpaceRef
"Initially, gravity acted on slight density fluctuations present shortly after the Big Bang to pull together the first clumps of dark matter. These grew into larger and larger clumps through the hierarchical merging of smaller progenitors. This is the process the UCSC researchers simulated on the Columbia supercomputer at the NASA Ames Research Center, one of the fastest computers in the world. The simulation took a couple of months to complete, running on 300 to 400 processors at a time for 320,000 'cpu-hours,' Diemand said.
Coauthor Michael Kuhlen, who began working on the project as a graduate student at UCSC and is now at the Institute for Advanced Study in Princeton, said the researchers set the initial conditions based on the most recent results from the Wilkinson Microwave Anisotropy Probe (WMAP) experiment. Released in March, the new WMAP results provide the most detailed picture ever of the infant universe.
The simulation starts at about 50 million years after the Big Bang and calculates the interactions of 234 million particles of dark matter over 13.7 billion years of cosmological time to produce a halo on the same scale as the Milky Way's. The clumps within the halo are the remnants of mergers in which the cores of smaller halos survived as gravitationally bound subhalos orbiting within the larger host system. "

Friday, November 10, 2006

"Blind mice treated with stem cells regain sight"

Times Online
"The cells used by the team have been programmed to be, but have yet to become, mature photoreceptors. This means that once transplanted, they are primed and ready to integrate with the retina.
A second encouraging feature of the research, reported in Nature, is that the retina accepted the new cells.
Jane Sowden, co-leader of the research, said: “Remarkably, we found that the mature retina, previously believed to have no capacity for repair, is in fact able to support the development of new functional photoreceptors.”
It seems possible that the eye already possesses a source of such cells. On the margin of the retina there are cells with stem cell-like properties — that is, cells capable of self-renewal."

Wednesday, November 01, 2006

Brainstem abnormality linked with SIDS

"The latest research, led by David Paterson and colleagues at Children's Hospital Boston and the Harvard Medical School, compared brain tissue from 31 infants who died of SIDS with samples from 10 babies who died of other causes.

The scientists focused on an area of the brainstem called the medulla, which regulates breathing, sleep-and-wake cycles and other vital functions, The New York Times reported.
The results of the study suggest a physical abnormality, most likely genetic, interferes with how neurons process serotonin and might lead to a diagnostic test for SIDS risk."