University Times

Nanoscience research reported

Pitt nanoscience researchers presented results of their work at the national meeting of the American Chemical Society this week.

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Explosion-proof microreactors

Assistant professor of chemical engineering Goetz Veser discussed his design for safer reactors for the power industry.

Reactors that mix air with hydrogen or natural gas to produce energy can explode when the reaction gets too hot or when free radicals break away and speed up the reaction.

Veser’s microreactors won’t explode regardless of temperature or the gas composition. And they keep pollutants such as nitrogen oxides (NOx) from forming.

“Even if the temperature goes completely through the roof, based on the kinetics of the system, explosions cannot happen,” Veser said.

Veser created the reactors by etching tiny channels into silicon chips, using a platinum wire catalyst and running a mix of hydrogen and air through the channel. He got a controlled burn or hydrogen and found the walls of the channel adsorb free radicals, keeping the reaction running smoothly.

His results could be used to design processes for safe, clean energy production and hydrogen storage.

Veser has since extended the technology to burning methane and found that at a particular size, microreactor walls adsorb the radicals that cause NOx.

“This is a completely different way of approaching a clean combustion technology,” he said.

Veser’s research is supported by a National Science Foundation CAREER Award.

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Nanotube research presented

John T. Yates Jr., R.K. Mellon Professor of Chemistry and Physics, and J. Karl Johnson, William Kepler Whiteford Professor of Chemical Engineering, have extensively investigated the use of single-walled carbon nanotubes (SWNTs) as tiny test tubes. SWNTs are cylindrical molecules with a diameter equivalent to about three atoms and walls made of a single curved sheet of carbon atoms.

The pair recently discovered that water molecules inside nanotubes bond in rings of seven that stack like doughnuts along the nanotube, held together by a new type of hydrogen bond.

The researchers first detected this novel hydrogen bond experimentally by its unusual singular vibrational frequency and later deduced its character by modeling.

In another development, research showed that nanotube walls shield the reactive molecules confined from reacting with active chemical species like atomic hydrogen. The work suggests that chemists could keep certain molecules from reacting by storing them inside nanotubes, while molecules outside the tube are free to react. “This could provide a new tool for focusing reactive chemistry in the laboratory to select one molecule and exclude another one, tucked away inside of a nanotube,” Yates said.

The researchers’ work could lead to future SWNT-based technologies such as time-release medications and highly efficient gas masks to decontaminate toxic gases. In addition, their research promises to yield new insights into basic chemistry. “Confining matter inside of nanotubes could lead to a range of new chemical and physical properties for the confined molecules, allowing chemists a higher degree of control of molecular behavior,” said Yates.

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Avian flu vaccine production funded

The National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health has awarded a $1.3 million, two-year grant to the School of Medicine to produce an avian flu vaccine that could be used in phase I and phase II human clinical trials.

Earlier this year, Pitt researchers reported in the journal Virology that their genetically engineered vaccine, which contains components of the deadly H5N1 virus but does not cause disease, completely protected mice and chickens from infection after exposure to the wild-type virus.

Andrea Gambotto, assistant professor in the medical school’s departments of surgery and molecular genetics and biochemistry and lead investigator on the project, said the funding will allow his group to begin making the vaccine soon.

“It will take us a few weeks to get our facility ready. However, we hope to begin vaccine production by early fall,” he said.

Because this vaccine contains a live virus — a modified common cold virus called adenovirus — the Pitt investigators believe it may be more effective in stimulating a therapeutic immune response than avian flu vaccines prepared by traditional methods.

In addition, because the Pitt vaccine is grown in cells, it can be produced more quickly than traditional flu vaccines that take four-six months to produce. The faster production time makes the vaccine an attractive candidate for preventing the spread of the virus in both domestic livestock populations and in humans.

In addition, other studies show that such vaccines can protect against more than one strain of the virus.

Since their initial report, Gambotto’s team has refined the vaccine by adding more H5N1 immune-stimulating proteins, which they believe will make it even more effective against different strains of the virus.

Gambotto said he is hopeful that NIAID will be interested in comparing the effectiveness of his vaccine to others already tested in federally funded clinical trials.

Those vaccines, produced by GlaxoSmithKline and Sanofi Pasteur, stimulated what is considered an adequate immune response in only one-half to three-quarters of healthy people who were inoculated.

“Testing our vaccine in the same protocol as the previous two is the only way to tell if ours is as good, better or worse,” said Gambotto.

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Concern about weight may affect new moms’ smoking

Prenatal and postnatal exposure to smoke has been linked to sudden infant death syndrome, ear infections, respiratory illness and asthma. Risks to adults include cancer and respiratory and reproductive complications.

But although many women quit smoking during pregnancy, the majority will resume smoking after having a baby. Results of a School of Medicine study published in the Annals of Behavioral Medicine suggest that worries about weight may decrease women’s motivation to remain smoke-free postpartum.

“Two-thirds of women who quit smoking when pregnant will resume smoking after giving birth,” said Michele Levine, assistant professor of psychiatry in the medical school. “We want to understand how factors, such as depression or the baby blues, and weight concerns, might affect women’s motivations to smoke after delivery.

“Weight concerns are a prevalent problem among American women, and can affect women who have recently given birth,” Levine said. “In women who quit smoking when they become pregnant, we found that concerns about weight can make them less motivated to stay smoke-free after pregnancy.”

The researchers interviewed 119 women who had smoked at least eight cigarettes per day for at least one month prior to quitting, and who quit after learning they were pregnant. Most of the women, 89 percent, reported quitting on their own without the help of formal programs or materials. During their third trimester, the women completed a series of paper-and-pencil questions about their motivation and confidence for remaining abstinent and their confidence to control their weight without smoking after giving birth. Based on their responses, the women were then divided into two groups, those who were highly motivated not to smoke after giving birth, and those who were less motivated.

A majority — 65 percent —were highly motivated to remain smoke-free, and 74 percent of those women felt confident that they would be able to do so. The researchers found that the more confident a woman was that she could maintain her weight without smoking, the more motivated she was to remain a nonsmoker postpartum. Those who were less confident in their ability to control their weight were less motivated to remain smoke-free.

“The next step is to see if weight concerns play a role in women’s actual behavior, beyond motivation, and to understand the best way to target this vulnerability with treatment,” said Levine.

“The risks of smoking to both mother and child are well known; hopefully, we will learn about ways to help women reduce the dangers that cigarette exposure can pose to themselves and their children.”

The study was funded by the National Institute of Drug Abuse, one of the National Institutes of Health.

Co-authors include Marsha D. Marcus and Melissa Kalarchian of psychiatry, and Lisa Weissfeld and Li Qin of the Graduate School of Public Health’s biostatistics department.

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Young athletes safer when testing is part of concussion diagnosis

When it comes to managing concussions in sports, relying only on an athlete’s self report of symptoms is inadequate and likely to result in under-diagnosing the injury and the athlete unsafely returning to play following the concussion, warn doctors at the UPMC sports medicine concussion program.

Along with assessing symptoms, the doctors stress, using computer-based neurocognitive function testing is crucial for accurate, objective evaluation of concussion and determining a safe return-to-play time for the athlete.

“Because of the tendency of some athletes to under-report their symptoms, presumably in an attempt to speed their return to the playing field, neurocognitive testing following suspected concussion is particularly important in keeping kids safe,” said Mark Lovell, an assistant professor in orthopaedic surgery at the medical school and director of the UPMC concussion program.

Lovell’s alert is based on his recent study of concussed high school and college athletes that showed unreliability of the athletes’ self-reported symptoms and demonstrated the value of neurocognitive testing in significantly increasing the capacity to detect post-concussion abnormalities, decreasing the potential of exposure to additional injury.

Previous research has shown that young concussed athletes who are returned to play too soon, before their brains have healed, are highly vulnerable to further injury, including post-concussion syndrome, or in rare cases, fatal second-impact syndrome. The current study is published in the upcoming issue of the American Journal of Sports Medicine, available online at www.ajsm.org.

“This research further proves what we have learned from years of experience in our clinic — that even athletes who report being symptom-free may continue to exhibit neurocognitive deficits that they are either unaware of or are failing to report.”

The current study involved 122 concussed high school athletes, all of whom had undergone pre-season neurocognitive function baseline testing with ImPACT (Immediate Post-Concussion Assessment and Neurocognitive Testing) as well as ImPACT testing again post-concussion to compare to baseline. Sixty-four percent of the concussed athletes reported a significant increase in symptoms compared to their pre-injury baselines at two days’ post-injury and 83 percent had significantly poorer neurocognitive test results relative to their own baseline performance. Therefore, the addition of neurocognitive testing resulted in a net increase in sensitivity of 19 percent.

The use of both symptom and neurocognitive test scores resulted in an increased sensitivity of 29 percent over reliance on symptoms alone.

“Generally, an athlete who sustains an initial concussion can fully recover as long as the brain has had time to heal before sustaining another hit,” said Micky Collins, study co-author and assistant director of the UPMC program. “The tricky part is that concussion signs and symptoms are not always straightforward and the effects and severity of the injury can be difficult to determine. Symptoms can typically occur with no visual indication by medical personnel and traditional neurodiagnostic tests such as CT, MRI and EEG are generally insensitive in measuring the subtle neurological changes following injury; thus, the need for careful clinical evaluation of symptoms in addition to objective neurocognitive testing.”

ImPACT — a computer-based test battery — is used by more than 900 high schools, 250 colleges and universities and 125 professional sports teams nationwide and in 250 sports medicine clinics and numerous other national and international athletic organizations. It can measure precisely even the subtle effects of a concussion, such as decline in memory, visual motor skills, information-processing speed and reaction time, as well as symptom levels. Athletes can take an individual pre-season baseline test where data is stored for comparison with post-injury test scores, should an athlete sustain a concussion during the season.

“A concussed athlete should never be cleared for return to play until neurocognitive scores on tests such as ImPACT match pre-injury baseline scores and all reported symptoms have resolved both at rest and at exertion,” said Collins.

Other authors of the current UPMC study are Jamie Pardini and , of the School of Medicine’s orthopaedic surgery department and UPMC, and Derk Van Kampen, who is completing his medical training in the Netherlands.

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Engineering nets nano grant

The School of Engineering has received a nanotechnology undergraduate education (NUE) grant from the National Science Foundation. This two-year, $200,000 award, Pitt’s first, is one of 10 granted for 2007 in the nation.

The NUE award focuses on nanoscale engineering education with an emphasis on introducing nanoscale science, engineering and technology.

In this program, principal investigator Minhee Yun of electrical and computer engineering will create a 3-credit course on integrated nanoscale science and engineering for sophomore-level students and above in engineering, chemistry, physics or related specializations, including medicine.

An interdisciplinary faculty team, including a professor of electrical engineering and a professor of chemistry, will be responsible for developing and instructing this research-oriented course that aims to introduce nanoscale devices created from a range of nanomaterials such as carbon nanotubes, nanoparticles and nanowires.

Teams of students will prepare proposals for summer research based on nanomaterials and one group will be selected to do its proposed research at a related laboratory in the Institute of NanoScience and Engineering with a paid summer research stipend.

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Chemistry prof receives 2 NSF grants

David W. Pratt, professor of chemistry, recently received two grants from the National Science Foundation for studies of the properties of biological molecules and their water complexes in the gas phase.

One grant, for $566,777, is a collaborative one with Brooks H. Pate at the University of Virginia, and focuses on the three-dimensional structures of several molecules relevant to life processes in their ground electronic states.

The second grant for $529,583 is a single investigator grant that focuses on changes in the structures of biomolecules that are produced by the absorption of light. A number of new measurement techniques will be developed at Pitt and the University of Virginia for both of these programs.

Pratt’s research at Pitt has been supported continuously by NSF for more than 25 years.

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Grant addresses minorities’ barriers to cancer care

UPMC Cancer Centers has been awarded $50,000 from the Lance Armstrong Foundation (LAF) to help health care professionals at the Hillman Cancer Center learn how they can better meet the needs of African Americans with cancer.

“The burden of cancer is too often greater for the poor, ethnic minorities and the uninsured,” said Joyce Grater, principal investigator of the grant and program coordinator at the Hillman Cancer Center. “It is vitally important for us to understand the factors that impede access to care in order to provide cancer services to patients, their families and communities with the greatest needs.”

According to Grater, some of the barriers experienced by African-American patients include transportation to and from treatment, housing problems and lack of health insurance.

The grant will be used to create a database to document and track the barriers to care experienced by African-American patients treated at the Hillman Cancer Center. Specialized care facilitators, or patient navigators, will be trained to resolve barrier-related problems by working closely with patients to meet their needs over a two-year period. The patient navigator will provide patients with emotional support, assistance navigating the health care system, and help accessing community resources.

“Over time, we expect to gain invaluable information about the types of barriers African-American patients experience, the frequency at which they occur and how best to resolve them,” said Grater. “We are extremely grateful to the Lance Armstrong Foundation for this opportunity.”

UPMC Cancer Centers is one of 27 non-profit organizations across the country to receive LAF grants this year to help people with the physical, emotional and practical challenges of cancer. Cancer survivor and champion cyclist Lance Armstrong founded LAF in 1997.

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SIS receives $1 million NSF grant for scholarships

The National Science Foundation (NSF) recently approved a $1 million scholarship program for the Security Assured Information Systems (SAIS) track at the School of Information Sciences. Over a four-year period, the program will support three cohorts of four graduate students in their pursuit of master’s and PhD degrees in information science or telecommunications and networking with the SAIS track option.

The scholarship program seeks to address the growing need for a workforce trained in the development, design, and implementation of secure information systems. Graduates of the SAIS track will be qualified to manage the security of large networks and infrastructures.

The scholarship program also will emphasize the recruitment of underrepresented groups in information assurance (IA) to gain a more diverse and wide-ranging pool of qualified IA professionals to serve the global community in protecting cyberspace.

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Therapeutic hypothermia research funded

The National Institutes of Health has awarded $1,027,500 to Sam Poloyac, assistant professor of pharmaceutical sciences, for research on the implications of hypothermia on hepatic drug metabolism.

This research is aimed at determining the effects of therapeutic hypothermia on drug elimination in animal models of cardiac arrest and traumatic brain injury.

The studies also seek to determine the implications of altered drug metabolism on the resultant brain damage, optimizing the therapeutic benefits of reduced body temperature after injury.