February 9, 2007, 4:38 AM CT

Nanotechnology meets biology

The object of fascination for most is the DNA molecule. But in solution, DNA, the genetic material that hold the detailed instructions for virtually all life, is a twisted knot, looking more like a battered ball of yarn than the famous double helix. To study it, researchers generally are forced to work with collections of molecules floating in solution, and there is no easy way to precisely single out individual molecules for study.

Now, however, researchers have developed a quick, inexpensive and efficient method to extract single DNA molecules and position them in nanoscale troughs or "slits," where they can be easily analyzed and sequenced.

The technique, which as per its developers is simple and scalable, could lead to faster and vastly more efficient sequencing technology in the lab, and may one day help underpin the ability of clinicians to obtain customized DNA profiles of patients.

The new work is reported this week (Feb. 8, 2007) in the Proceedings of the National Academies of Science (PNAS) by a team of researchers and engineers from the University of Wisconsin-Madison.

"DNA is messy," says David C. Schwartz, a UW-Madison genomics researcher and chemist and the senior author of the PNAS paper. "And in order to read the molecule, you have to present the molecule".........

Posted by: Kevin      Read more         Source

February 8, 2007, 9:57 PM CT

Effects Of Global Warming On Antarctic

The Intergovernmental Panel on Climate Change report citing the detrimental.

loss of sea ice sheets in the Arctic due to global warming echoes what a number of in the scientific community have been saying for years. Now scientists at The University of Texas at San Antonio's Department of Earth and Environmental Science are turning their attention to the South Pole to find out if global warming is having similar effects in the frigid Antarctic region.

UTSA Earth and Environmental Science Assistant Professor Hongjie Xie and doctoral student Burcu Cicek are analyzing data collected in December following a two-week trip to the region. The pair were part of.

an international expedition that included researchers and educators from the United States, Chile and Sweden.

The National Science Foundation (NSF) funded the 6,000 mile trip which was designed to allow.

researchers to collect data aboard the Swedish icebreaker Oden during transit from Punta Arenas, Chile to the United States' McMurdo Research Station on the Antarctic continent, south of New Zealand. The Oden was chartered by NSF to break through the ice and create a 25-mile long shipping channel that would allow for the delivery of annual supplies to NSF's McMurdo Research Station. On route to Antarctica, the ship passed through 1,700 miles of extensive sea ice cover that surrounds the continent annually.........

Posted by: Tyler      Read more         Source

February 8, 2007, 9:54 PM CT

Closest Gravitational Lensing Galaxy

A giant elliptical galaxy seen in an image from the Hubble Space Telescope is the closest gravitational lens yet known, according to information released by the Hubble Heritage Project.

John Blakeslee, an assistant professor with the Department of Physics and Astronomy at Washington State University, working with colleagues from the University of Hawaii and the University of Durham in England, targeted the galaxy for a closer look by Hubble.

"The galaxy was well-known, but the Hubble images reveal so much more detail about it, including the unexpected finding that it's the nearest gravitational lens," said Blakeslee.

A gravitational lens is a celestial object so huge that it has enough mass to deflect, magnify and focus light emitted by an object that is on the opposite side of it from Earth. The result is that when viewed from Earth, the more distant object appears as an arc or ring rather than a spot or spiral. Such images are known as "Einstein rings" because Albert Einstein first predicted them.

Despite the huge number of galaxies in the universe, said Blakeslee, "gravitational lensing is a rare occurrence because it requires an almost perfect alignment of a distant galaxy with an intervening one that has enough mass to gravitationally focus the light".........

Posted by: Brooke      Read more         Source

February 7, 2007, 9:38 PM CT

Risk of extinction accelerated due to human

The simultaneous effect of habitat fragmentation, overexploitation, and climate warming could accelerate the decline of populations and substantially increase their risk of extinction, a study reported in the Proceedings of the Royal Society B has warned.

Using experimental microcosm populations of rotifers (a type of zooplankton), the study observed that individually each of these threats caused significant population declines. The study also observed that the rate of declines was much accelerated when populations were exposed to more than one threat. These results indicate that multiple interacting threats are capable of causing rapid population extinction, and that all threats should be simultaneously reduced, if their synergies are to be avoided and if the current rate of species loss is to be reversed.

A number of scientific efforts have been made to link the decline of wild marine and terrestrial populations with human activities such as habitat fragmentation, overexploitation and global warming. "Establishing the link between the loss of biodiversity and human-related threats is crucial to develop policies aimed at mitigating such threats", says Camilo Mora at Dalhousie University, leading author of the paper. "Unfortunately, in a number of cases several threats are operating simultaneously making it difficult to isolate their individual and combined effects through field observations,"Mora adds.........

Posted by: Ashley      Read more         Source

February 7, 2007, 8:28 PM CT

Collisions Of The Earth's Crust Theory Challenged

New research findings may help refine the accepted models used by earth researchers over the past 30 years to describe the ways in which continents clash to form the Earth's landscape.

Eric Calais, an associate professor of geophysics at Purdue University, in collaboration with Ming Wang and Zenghang Shen from the Institute for Geology and Earthquake Science in China, used global positioning systems to record the precise movements of hundreds of points on the continent of Asia over a 10-year period.

"Previous to this, we had only partial regional views that were sometimes inconsistent with each other," Calais said. "With this work, we addressed a fundamental question that geologists have been debating for the past 40 years: Are continents strong and brittle or weak and viscous?".

The "strong and brittle" theory suggests continents break into pieces during collisions of the tectonic plates, pieces of the Earth's crust into which the continents are embedded. The "weak and viscous" theory suggests, on the contrary, that continents thicken and flow upon collision.

The data collected by Calais and his team, published in the Dec. 30 issue of Geophysical Research Letters, suggests the answer is a combination of both theories. His team observed that the surface of the Asian continent behaves differently in areas of high elevation, such as mountains.........

Posted by: William      Read more         Source

February 7, 2007, 8:24 PM CT

Forensic Photography Brings Color Back

Archaeologists are now turning to forensic crime lab techniques to hunt for dyes, paint, and other decoration in prehistoric textiles.

Eventhough ancient fabrics can offer clues about prehistoric cultures, often their colors are faded, patterns dissolved, and fibers crumbling. Forensic photography can be used as an inexpensive and non-destructive tool to analyze these artifacts more efficiently, as per new Ohio State University.

Forensic photography helps scientists collect information from fragile artifacts before using expensive chemical tests, which cause damage during material sampling. The forensic method also helps scientists narrow areas to sample for colorants, ultimately reducing artifact damage and testing costs.

"Normally when you dig artifacts out of the ground, particularly stone or ceramic ones, you wash them and they look sexy. But you can't do that with textiles," said Christel Baldia, Ohio State University doctoral graduate in textiles and clothing. Baldia conducted the study with Kathryn Jakes, professor of textile sciences in the College of Education and Human Ecology at Ohio State, and published their findings in the April, 2007 issue of Journal of Archaeological Science.

Putting forensic photography to the test, Baldia and Jakes examined textiles from burial mounds built by the Hopewell, a prehistoric Native American people that flourished about 1600 years ago. In their study, the two researchers focused on pieces of fabric recovered from Ohio 's Seip burial mounds in southern Ohio. Experts believe some of the pieces belonged to a canopy of fabric that arched over the remains buried inside the mounds.........

Posted by: William      Read more         Source

February 7, 2007, 4:53 AM CT

Cold storage solution for global warming?

Scientists from the University of Leicester and the British Geological Society (BGS) have proposed storing CO2 in huge underground reservoirs as a way of reducing emissions- and have even identified sites in Western Europe that would be suitable.

Their research, reported in the journal, Planet Earth, reveals that CO2 can be contained in cool geological aquifers or reservoirs, where it can remain harmlessly for a number of thousands of years.

PhD research student, Ameena Camps, is working with Professor Mike Lovell at the University's Department of Geology and with Chris Rochelle at BGS, investigating the storage of CO2.

Storing the gas in a solid form as a gas hydrate, or as a pool of liquid CO2 below a cap of hydrate cemented sediments, is believed to offer an alternative method of geological sequestration to the current practices of storage in warm, deep sediments in the North Sea.

Recently quoted in Planet Earth Ameena Camps explained: "Hydrates (also known as clathrates) are ice-like crystalline minerals that look like normal ice and form when gas and water freeze together at low temperature and high pressure. They are made of a cage of frozen water molecules with the gas molecules trapped inside".

Eventhough gas hydrates were first discovered two centuries ago, the possible use of carbon dioxide hydrate as a means to help resolve problems of global climate change, and of naturally occurring methane hydrate as a future source of energy, have only recently been suggested.........

Posted by: Tyler      Read more         Source

February 6, 2007, 9:53 PM CT

Are You My Mother?

Mama Fox can often be found with her kits, tossing tennis balls, crawling on her hands and knees in their playpen, and making a game out of chasing crickets. Even though "Mama" is a tailless, fur-less giant in comparison to the tiny fennec fox kits, the three youngsters have grown used to her parenting ways, and enjoy an afternoon nap in her lap.

Mama Fox is better known as Kathleen LaMattina, Animal Programs Liaison for the Wildlife Conservation Society's Bronx Zoo. Kathleen supervises and manages the Zoo's Tractable Animal Collection-a group of more than 300 animals that participate in education and outreach programs. The particularly social fennec foxes are among the zoo's best-loved animal ambassadors, often accompanying Bronx Zoo instructors to school programs, as well as meeting and greeting children and adults at zoo-based programs.

Fennec foxes aren't shy in a crowd. In their wild habitat, North Africa's Sahara Desert and the northern part of Saudi Arabia, these animals live in groups of up to ten individuals. Their bodies are well suited to the harsh conditions of their desert home-large ears enable them to get rid of excess body heat, fur on the soles of their paws help protect them from the hot sand, and buff-colored coats help them blend in.

Kit Kinder Care: Naptime, Playtime, and Hunting Lessons.........

Posted by: Ashley      Read more         Source

February 6, 2007, 9:50 PM CT

Createing Undersea Hills

As per 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 researchers ever since they were first discovered in the 1940s.

Writing in the January issue of Geophysical Research Letters, MBARI geologists Charlie Paull and William Ussler and their coauthors described the results of field work they conducted on the Beaufort Sea Shelf, offshore of the north coast of Canada. In this area of year-round sea ice and permafrost, the team spent over a month mapping the seafloor and collecting sediment cores and gas samples from these underwater hills, which they call "pingo-like features."

"Pingos," small, dome-shaped, ice-cored hills, are found in many Arctic regions. "Pingo-like features" are similar in shape and size to pingos on land, but are found underwater, on the continental shelf in several parts of the Arctic. Previous studies have suggested that pingo-like features are pingos that formed on land but were submerged when sea level rose following the end of the last ice age, over 10,000 years ago.

Based on their geologic fieldwork and subsequent chemical analysis of the gas and sediments from eight pingo-like features, Paull and his coauthors propose an alternative hypothesis: Pingo-like features form when methane hydrate (a frozen mixture of gas and seawater) decomposes beneath the seafloor, releasing gas that squeezes deep sediments up onto the seafloor like toothpaste from a tube.........

Posted by: Tyler      Read more         Source

February 6, 2007, 9:29 PM CT

Man-made Proteins Could Be More Useful

Scientists have constructed a protein out of amino acids not found in natural proteins, discovering that they can form a complex, stable structure that closely resembles a natural protein. Their findings could help researchers design drugs that look and act like real proteins but won't be degraded by enzymes or targeted by the immune system, as natural proteins are.

The researchers, led by Howard Hughes Medical Institute (HHMI) professor Alanna Schepartz, report their findings in the February 14, 2007, issue of the Journal of the American Chemical Society, published in advance online on January 19, 2007. Schepartz and her coauthors, Douglas Daniels, James Petersson, and Jade Qiu, are all at Yale University. A story in the February 5, 2007, issue of Chemical & Engineering News spotlighted the research.

As an HHMI professor, Schepartz received a $1 million grant to find ways to infuse undergraduate teaching with the excitement of research. Several of her HHMI undergraduates synthesized beta-amino acid monomers that were used to prepare the synthetic protein.

Schepartz and his colleagues built the short protein, or peptide, from ß-amino acids, which, eventhough they exist in cells, are never found in ribosomally produced proteins. ß-amino acids differ from the alpha-amino acids that compose natural proteins by the addition of a single chemical component-a methylene group-into the peptide backbone.........

Posted by: Sarah      Read more         Source