The brain might work more like an assembly line when recognizing objects, with a hierarchy of brain regions separately absorbing and processing information before a person realizes what they are seeing, according to new research conducted at the University of Pittsburgh and published in the Journal of Neuroscience.

Led by Mark Wheeler, a psychology professor in Pitt’s School of Arts and Sciences, the research is a step toward mapping the human decision-making process. This study used an innovative technique and analysis to show that human decision-making is a collaboration of brain regions performing individual functions.

Scientists have described the oldest definitive jellyfish ever found, using recently discovered "fossil snapshots" found in rocks more than 500 million years old.

The jellyfish are unique because they push the known occurrence of jellyfish back from 300 million to 505 million years.

"This study clearly shows what paleontologists have long suspected--that jellyfish have a history that's much older than their known fossil record," said Patrick Herendeen, program director in the National Science Foundation (NSF)'s division of environmental biology, which funded the research through the Assembing the Tree of Life (AToL) program, along with NSF's division of earth sciences. "Adding some 200 million years to the age of jellyfish is quite a jump.

A discovery about the genetics of coat color in dogs could help explain why humans come in different weights and vary in our abilities to cope with stress, a team led by researchers from the Stanford University School of Medicine reports.

The study, published in the Nov. 2 issue of Science, answers a longtime mystery: What determines coat color in dogs? While researchers have known since the 1900s that most mammals share the same genetic mechanism to determine coat color, by the 1950s they began to suspect that dogs were different.

Now after swabbing the inner cheeks of hundreds of dogs and analyzing the DNA in the resulting samples, a team led by genetics professor Greg Barsh, MD, PhD, has nailed the gene.

Unprecedented fossilized body imprints of amphibians have been discovered in 330 million-year-old rocks from Pennsylvania. The imprints show the unmistakably webbed feet and bodies of three previously unknown, foot-long salamander-like critters that lived 100 million years before the first dinosaurs.

"Body impressions like this are wholly unheard of," said paleontologist Spencer Lucas, a curator at the New Mexico Museum of Natural History and Science. Lucas will present the discovery on Tuesday, 30 October 2007, at the annual meeting of the Geological Society of America in Denver.

Fame was fleeting for the 16-solar-mass black hole in the galaxy M33, announced on October 17 as the record holder for the heaviest black hole orbiting a star.

A new black hole, with a mass 24 to 33 times that of our Sun, is more massive than scientists have detected - or expected - for a black hole that formed from a dying star.

The newly discovered object belongs to the category of "stellar-mass" black holes. Formed in the death throes of massive stars, they are smaller than the monster black holes found in galactic cores.

You can call it optical tweezers, microtools for chips, or even a cellular Death Star. MIT researchers have found a way to use a “tractor beam” of light to pick up, hold, and move around individual cells and other objects on the surface of a microchip.

The idea of using light beams as tweezers to manipulate cells and tiny objects has been around for at least 30 years. But the MIT researchers have found a way to combine this powerful tool for moving, controlling and measuring objects with the highly versatile world of microchip design and manufacturing.

Optical tweezers, as the technology is known, represent “one of the world's smallest microtools,” says assistant professor Matthew J. Lang. “Now, we're applying it to building [things] on a chip.”

A pair of galaxies, known collectively as Arp 87, is one of hundreds of interacting and merging galaxies known in our nearby Universe. Arp 87 was originally discovered and catalogued by astronomer Halton Arp in the 1970s. Arp’s Atlas of Peculiar Galaxies is a compilation of astronomical photographs using the Palomar 200-inch Hale and the 48-inch Samuel Oschin telescopes.

The resolution in the Hubble image shows exquisite detail and fine structure that was not observable when Arp 87 was first discovered in the 1970’s.

New research is the first to definitively pinpoint when and from where HIV-1 entered the United States and shows that most HIV/AIDS viruses in the U.S. descended from a single common ancestor. The actual ancestral HIV entered the U.S. long before the storied "Patient Zero," senior author Michael Worobey said.

The AIDS virus entered the United States via Haiti, probably arriving in just one person in about 1969, earlier than previously believed, according to new research.

After the virus, HIV-1, entered the U.S., it flourished and spread worldwide.

Reporting in the Oct. 29 online edition of the Proceedings of the National Academy of Science, Edythe London, a professor of psychiatry in the UCLA Semel Institute for Neuroscience and Human Behavior; Kate Baicy, a graduate student in London’s lab, and colleagues report that leptin reduces activation in regions of the brain linked to hunger while enhancing activation in regions linked to inhibition and satiety. The findings suggest possible new therapeutic targets for human obesity, an increasing problem in adults as well as children.

The researcher’s used functional magnetic resonance imaging (fMRI) to measure brain activity before and after leptin supplementation in three adults from a Turkish family who lacked the leptin (ob) hormone due to a mutation.