August 20, 2008, 6:12 PM CT

New 'nano-positioners' may have atomic-scale precision

Engineers have created a tiny motorized positioning device that has twice the dexterity of similar devices being developed for applications that include biological sensors and more compact, powerful computer hard drives.

The device, called a monolithic comb drive, might be used as a "nanoscale manipulator" that precisely moves or senses movement and forces. The devices also can be used in watery environments for probing biological molecules, said Jason Vaughn Clark, an assistant professor of electrical and computer engineering and mechanical engineering, who created the design.

The monolithic comb drives could make it possible to improve a class of probe-based sensors that detect viruses and biological molecules. The sensors detect objects using two different components: A probe is moved while at the same time the platform holding the specimen is positioned. The new technology would replace both components with a single one - the monolithic comb drive.

The innovation could allow sensors to work faster and at higher resolution and would be small enough to fit on a microchip. The higher resolution might be used to design future computer hard drives capable of high-density data storage and retrieval. Another possible use might be to fabricate or assemble miniature micro and nanoscale machines......... Posted by: Beverly      Read more         Source

August 20, 2008, 1:37 AM CT

Transition From Home To College

An increasing number of students are packing more than their computers and iPods when leaving for college. They are bringing along prescribed psychiatric medications.

And once on campus, experiencing new freedom from supervision by mom, dad and hometown mental health providers in taking those medications may present an opportunity to experiment with stopping those meds.

As per the Association for University and College Counseling Center Directors Annual Survey in 2007, 87 percent of the center reported an increase in the number of students coming for counseling were taking psychotropic medications. The National American College and University Health Services reports that about 20 percent of the students visiting counseling centers are on prescribed medications for a range of mental illnesses from depression, bipolar disorder to attention deficit disorder.

This has scientists and mental health counselors on campuses concerned about whether counseling centers are meeting all the needs of these students. That concern has become the focus of a new Case Western Reserve University study about how students manage their mental illnesses.

This fall, Jerry Floersch of the Mandel School of Applied Social Sciences; Eileen Anderson-Fye, an assistant professor of anthropology; and Jes Sellers, director of the University Counseling Center and adjunct assistant professor of psychology and clinical instructor in the department of psychiatry, will begin a two-year, $75,000 Presidential Research Initiative study, "College Student Experience of Mental Health Service Use and Psychiatric Medication."........ Posted by: Beverly      Read more         Source

August 18, 2008, 9:03 PM CT

Fungus helps beetles to digest hard wood

A little known fungus tucked away in the gut of Asian longhorned beetles helps the insect munch through the hardest of woods according to a team of entomologists and biochemists. Researchers say the discovery could lead to innovative methods of controlling the invasive pest, and potentially offer more efficient ways of breaking down plant biomass for generating biofuels.

Microbes in the gut of insects are known to break down cellulose, but little is known about how, or whether, insects degrade lignin. This natural polymer helps plants stay upright and protects them from most forms of microbial attack.

"Lignin is nature's plastic and any organism that wants to get to the sugars in a plant has to be able to get past this protective barrier," said Ming Tien, study co-author and Penn State professor of biochemistry and molecular biology. "We suspect that the fungus produces enzymes that help the beetles degrade lignin".

Before this report, it was thought that insects are unable to extensively break down lignin, and that they get around the problem either by feasting on wood that has already degraded, or by living close to fungi that can degrade the wood for them.

But this theory fails to explain the ability of insects to feed and grow within healthy living trees......... Posted by: Beverly      Read more         Source

August 18, 2008, 9:01 PM CT

Novel fungus helps beetles to digest hard wood

University Park, Pa. -- A little known fungus tucked away in the gut of Asian longhorned beetles helps the insect munch through the hardest of woods according to a team of entomologists and biochemists. Researchers say the discovery could lead to innovative methods of controlling the invasive pest, and potentially offer more efficient ways of breaking down plant biomass for generating biofuels.

Microbes in the gut of insects are known to break down cellulose, but little is known about how, or whether, insects degrade lignin. This natural polymer helps plants stay upright and protects them from most forms of microbial attack.

"Lignin is nature's plastic and any organism that wants to get to the sugars in a plant has to be able to get past this protective barrier," said Ming Tien, study co-author and Penn State professor of biochemistry and molecular biology. "We suspect that the fungus produces enzymes that help the beetles degrade lignin".

Before this report, it was thought that insects are unable to extensively break down lignin, and that they get around the problem either by feasting on wood that has already degraded, or by living close to fungi that can degrade the wood for them.

But this theory fails to explain the ability of insects to feed and grow within healthy living trees......... Posted by: Beverly      Read more         Source

July 30, 2008, 0:15 AM CT

Improved estrogen reception may sharpen fuzzy memory

Estrogen therapys may sharpen mental performance in women with certain medical conditions, but University of Florida scientists suggest that recharging a naturally occurring estrogen receptor in the brain may also clear cognitive cobwebs.

The discovery suggests that drugs can be developed to offset "senior moments" correlation to low estrogen levels, as well as to protect against neurological diseases, all while avoiding the problems linked to adding estrogen to the body.

Writing online in Molecular Therapy in July, researchers with UF's McKnight Brain Institute describe how they improved thought processes in female mice bred with the inability to produce estrogen receptor-alpha, a protein apparently necessary for healthy learning and memory.

"We were able to restore function in these animals, not by dosing them with estrogen, but by enabling them to use the estrogen that was naturally present in their bodies," said Tom Foster, Ph.D., the Evelyn F. McKnight chair for brain research in memory loss at the UF College of Medicine. "We discovered that you can affect the estrogen receptor directly in the hippocampus, right where it's needed to address memory and spatial learning".

Changes in the estrogen receptor have been linked to age-related memory deficits and an increased occurence rate of Alzheimer's disease among women. In addition, prior studies have shown estrogen replacement may improve cognition in postmenopausal women and younger women with low estrogen levels. Estrogen also appears to protect against Alzheimer's disease and dementia......... Posted by: Beverly      Read more         Source

July 23, 2008, 4:49 PM CT

Biofilms use chemical weapons

Bacteria rarely come as loners; more often they grow in crowds and squat on surfaces where they form a community together. These so-called biofilms develop on any surface that bacteria can attach themselves to. The dilemma we face is that neither disinfectants and antibiotics, nor phagocytes and our immune system can destroy these biofilms. This is a particular problem in hospitals if these bacteria form a community on a catheter or implant where they could potentially cause a serious infection. Researchers at the Helmholtz Centre for Infection Research in Braunschweig have now identified one of the fundamental mechanisms used by the bacteria in biofilms to protect themselves against the attacking phagocytes. The researchers are now publishing their findings in the renowned specialist publication PLoS ONE, together with colleagues from Australia, Great Britain and the USA the discovery being that biofilm bacteria use chemical weapons to defend themselves.

Until now, researchers have been unable to understand the root of the biofilm problem the inability of phagocytes to destroy these biofilms. Dr. Carsten Matz decided to investigate this problem. As a model for his investigation, this Braunschweig-based researcher decided to look at marine bacteria. They face constant threats in their habitat from environmental phagocytes, the amoebae, which behave in a similar way in the sea as the immune cells in our body: they seek out and feed on the bacteria. So long as bacteria are swimming freely and separately in the water, they are easy pickings for these predators. However, if they become attached to a surface and socialize with other bacteria, the amoebae can no longer successfully attack them. "The surprising thing was that the amoebae attacking the biofilms were de-activated or even killed. The bacteria are clearly not just building a fortress, they are also fighting back," says Carsten Matz......... Posted by: Beverly      Read more         Source

July 22, 2008, 8:24 PM CT

Studying Little-known But Largely Useful Microbes

Montana State University microbiologist Matthew Fields spends his days trying to understand how interactions on a microscopic scale could change how we think of energy production, climate change and even soil contamination.

Fields studies the physiology and behavior of microbes - the tiny organisms that have inhabited virtually every square inch of the earth's surface for the past 3.5 billion years.

"Microbes have global impacts," Fields said. "They can grow fast and in large numbers, and there is always power in numbers".

Fields is especially interested in how that power can be harnessed for human use. Last year, he received a five-year $1.65 million grant from the Department of Energy to study how microbes living together interact.

The grant is part of the Virtual Institute for Microbial Stress and Survival, a project led by the Lawrence Berkeley National Laboratory. Fields' work involves scientists at MSU and five other universities across the country, as well as researchers at three national laboratories.

Fields, who works at MSU's Center for Biofilm Engineering, said people are generally only aware of the microbes that make humans sick, such as E. coli. But those notorious species represent only a drop in earth's microbial ocean......... Posted by: Beverly      Read more         Source

July 22, 2008, 8:20 PM CT

Boosting Access to Clean Water

A chemical engineering professor at The University of Texas at Austin is part of a team that has developed a chlorine-tolerant membrane that should simplify the water desalination process, increasing access to fresh water and possibly reducing greenhouse gases.

"If we make the desalination process more efficient with better membranes, it will be less expensive to desalinate a gallon of water, which will expand the availability of clean water around the world," Professor Benny Freeman says.

The research will be published July 28 in the German Chemical Society's journal Angewandte Chemie.

Freeman worked primarily with James E. McGrath of Virginia Tech University and Ho Bum Park of the University of Ulsan in South Korea for more than three years to develop the chlorine-tolerant membrane made of sulfonated copolymers. A patent has been filed.

Chlorine must be added to water to disinfect it to prevent a biofilm (stemming from biological contaminants in the raw water) from forming on the membrane, which would reduce its performance. It is then de-chlorinated previous to sending it through the currently used polyamide membranes, which don't tolerate chlorinated water.

"It promises to eliminate de-chlorination steps that are mandatory currently to protect membranes from attack by chlorine in water," Freeman says. "We think that even a small increase in efficiency should result in large cost savings"......... Posted by: Beverly      Read more         Source

July 22, 2008, 8:10 PM CT

Robot playmates may help children with autism

Papers delivered at three conferences in the US and Europe this summer report on new research at the University of Southern California Viterbi School of Engineering studying interactions of children with Autism Spectrum Disorders (ASD) with bubble-blowing robots.

The preliminary studies, by Professor Maja Matarić and PhD student David Feil-Seifer of the USC Interaction Laboratory, confirm what has been widely reported anecdotally: that ASD children in a number of cases interact more easily with mechanical devices than with humans.

Matarić and Feil-Seifer, both specialists in Socially Assisted Robotics (SAR), are now engaged in further research to confirm their findings, and to develop a robot "control architecture" which will tailor robot interactions to the specific needs of ASD children to help therapists treating their condition.

The initial study, published in the June Conference on Interaction Design for Children with Special Needs in Chicago, tested whether interaction as opposed to simple passive observation was going on between ASD children and a colorful bubble-blowing wheeled robot.

The robot had two settings. In one, it carried on its rolling and bubble blowing on its own internal schedule, regardless of the behavior of the child. In the other, "when the child pushes a button, then the bubbles blow," in the words of the Chicago presentation......... Posted by: Beverly      Read more         Source

July 21, 2008, 9:44 PM CT

Motivations for tattoo removal

Individuals who visit dermatology clinics for tattoo removal are more likely to be women than men, and may be motivated by the social stigma associated with tattoos and negative comments by others, according to a report in the recent issue of Archives of Dermatology, one of the JAMA/Archives journals.

About one-fourth of adults age 18 to 30 have a tattoo, according to background information in the article. "While the vast majority of individuals who are tattooed are pleased with their skin markings (up to 83 percent), the popularity and prevalence of tattoos often mean that dermatologists are increasingly hearing stories of regrets and requests for tattoo removal," the authors write. About one-fifth of tattoo wearers are estimated to be dissatisfied with their tattoo, although only about 6 percent seek removal.

Myrna L. Armstrong, Ed.D., R.N., F.A.A.N., of the Texas Tech University Health Sciences Center, Lubbock, Texas, conducted a survey of 196 individuals who visited one of four dermatology clinics for tattoo removal in 2006. The 66 men and 130 women (average age 30) answered 127 questions about demographics, obtaining their tattoo and their motivations for seeking removal. Their answers were compared with responses to a similar survey conducted in 1996......... Posted by: Beverly      Read more         Source