University Times

Texting diverts in-class attention

College students who frequently text message in class have difficulty staying attentive to classroom lectures and consequently risk having poor learning outcomes, according to a new study available online and scheduled to appear in the July print issue of the National Communication Association’s journal Communication Education.

“We know from our past research that college students who are regular text users habitually engage in text messaging during class lectures,” said the study’s principal author, Fang-Yi Flora Wei, a Pitt-Bradford broadcast communications faculty member. “Now we see that in-class texting partially interferes with a student’s ability to pay attention, which prior studies show is necessary for effective cognitive learning.”

Wei said, “College students may believe that they are capable of performing multitasking behaviors during their classroom learning, such as listening to the lecture and texting simultaneously. But the real concern is not whether students can learn under a multitasking condition, but how well they can learn if they cannot sustain their full attention on classroom instruction.”

In the study, Pitt-Bradford students in selected general education classes completed an anonymous questionnaire at the end of the term. Students reported how many text messages they sent or received, on average, during the class that they attended immediately before their general education class.

Participants also rated themselves on specific learning variables including self-regulation (which Wei defined as “self-control in directing one’s learning process”), sustained attention and outcomes of cognitive learning — both self-reported grades and the perceived amount learned.

Because it is difficult to demonstrate that texting alone can have a direct impact on students’ cognitive learning, Wei said, she and her co-investigators used path model analysis to describe the relationships between texting, as a “mediator” or intervening variable, and cognitive learning.

Based on 190 completed questionnaires from students who attended a lecture-based class lasting 50 or 75 minutes, researchers found students viewed an average of 2.6 text messages in class and sent an average of 2.4 texts while in class. The researchers found no difference between the two class lengths in the extent of texting or students’ sustained attention to classroom learning.

They did find that students who possessed a high level of self-regulation were more likely to keep their attention focused on classroom learning. In turn, paying attention was related to improved cognitive learning, in terms of better grades and especially the perceived amount of learning, the authors reported.

These highly self-regulated students were less likely to text in class than students with lower levels of self-regulation, Wei said. Students who frequently texted during class were less likely to sustain attention to their instructor.

Wei said students should consider limiting their texting during class, adding that she thinks university-wide texting bans likely would be less effective than instructors using interactive instructional techniques or other strategies to keep students’ attention.

Co-authors were Pitt-Bradford faculty members Y. Ken Wang of management and education, and Michael Klausner of sociology.

The article, “Rethinking College Students’ Self-Regulation and Sustained Attention: Does Text Messaging During Class Influence Cognitive Learning?” is in the forthcoming articles  section at www.tandfonline.com/loi/rced20.

Radiation research presented

Radiation damage research by University of Pittsburgh Cancer Institute (UPCI) and Pitt School of Medicine scientists was presented recently at the annual meeting of the American Association for Cancer Research.

Mouse model developed

A team led by Joel Greenberger, chair of the medical school’s Department of Radiation Oncology, has developed a mouse model that will allow scientists to study radiation-induced genetic changes and cellular defense mechanisms against radiation exposure at the same time.

“Often side effects from radiation exposure occur right away, but some take anywhere from six months to two years to manifest,” said Greenberger. “Delayed side effects are caused either by genetic changes from radiation exposure or a breakdown in the body’s cellular defense mechanisms. In the past, we haven’t been able to study both causes at the same time. This new mouse model allows us to do that.”

Researchers created the model by engineering mice in which activity of the enzyme manganese superoxide dismutase (MnSOD) can be turned on if they are fed or injected with the antibiotic doxycycline. In healthy animals, radiation exposure leads to greater production of toxic free radicals such as superoxides, and in turn MnSOD levels rise to neutralize them. In the engineered mice that do not receive doxycycline, there is no MnSOD activity, and they survive only a few days.

Controlling activation of this enzyme will allow researchers to study the link between two categories of biochemical changes — acute changes caused by immediate radiation exposure and latent reaction that occurs months later. Researchers will be able to examine the antioxidant defense system and better understand molecular events that occur during asymptomatic periods.

The study was sponsored by the National Institute of Allergy and Infectious Diseases, an arm of the National Institutes of Health.

Radiation drug tracked

In other research, Greenberger and his team successfully labeled a drug that protects cells against radiation damage in order to better understand how it interacts inside human cells.

The work focused on labeling and tracking JP4-039, a drug that combats radiation-induced cell death by assisting the mitochondria, the energy generator of all cells.

JP4-039 was developed by Greenberger’s research team in conjunction with a team of chemists led by Peter Wipf, Distinguished Professor of Chemistry. Previous research has shown that the drug could offer protection from radiation-induced esophagitis, a painful inflammation of the esophagus, and could play a role in post-radiation exposure crises.

“With this study, we found a way to label JP4-039 so we can watch where it travels in the mitochondria,” Greenberger said. “This allows us to understand what it is binding to and how it acts. We can measure how much of the drug is delivered and where without interfering with its effectiveness. This is important because it is easier to study what the drug does to human cells and, conversely, what human cells do to the drug.”

Because the labeled drug, referred to as BODIPY JP4-039, can be rapidly detected once administered, Greenberger anticipates it will help further understanding of the radioprotection JP4-039 can offer.

This study was sponsored by the National Institutes of Health.

Neural variability, cognition studied

A team of Pitt mathematicians is using computational models to better understand how variability in neural structure relates to such functions as short-term memory and decision-making.

In a paper published online April 2 in Proceedings of the National Academy of Sciences (PNAS) the Pitt team examined how fluctuations in brain activity can impact the dynamics of cognitive tasks.

Previous recordings of neural activity during simple cognitive tasks show a tremendous amount of trial-to-trial variability. For example, when a person was instructed to hold the same stimulus in working (short-term) memory during two separate trials, the brain cells involved in the task showed very different activity during the two trials.

“A big challenge in neuroscience is translating variability expressed at the cellular and brain-circuit level with that in cognitive behaviors,” said mathematics faculty member Brent Doiron, the project’s principal investigator. “It’s a fact that short-term memory degrades over time. If you try to recall a stored memory, there likely will be errors, and these cognitive imperfections increase the longer that short-term memory is engaged.”

Doiron explained that brain cells increase activity during short-term memory functions but this activity randomly drifts over time as a result of stochastic (or chance) forces in the brain. This drifting is what Doiron’s team is trying to better understand.

“As mathematicians, what we’re really trying to do is relate the structure and dynamics of this stochastic variability of brain activity to the variability in cognitive performance,” said Doiron. “Linking the variability at these two levels will give important clues about the neural mechanisms that support cognition.”

Using a combination of statistical mechanics and nonlinear system theory, the Pitt team examined the responses of a model of a simplified memory network proposed to be operative in the prefrontal cortex. When sources of neural variability were distributed over the entire network, as opposed to only over subsections, the performance of the memory network was enhanced.

This helped the Pitt team make the prediction published in PNAS, that brain wiring affects how neural networks contend with — and ultimately express — variability in memory and decision-making.

Experimental neuroscientists are gaining a better understanding of how the brain is wired, and theories such as those published in PNAS by Doiron’s group give a context for their findings within a cognitive framework.

The Doiron group plans to apply the general principle of linking brain circuitry to neural variability in a variety of sensory, motor and memory/decision-making frameworks.

Pitt co-authors included Amber Polk, a 2011 Pitt graduate who now is studying law at the University of Illinois, and Ashok Litwin-Kumar, a neural computational PhD candidate with the Center for the Neural Basis of Cognition.

Funding for this research was provided by the National Science Foundation and Sloan Foundation.

Coaches can cut teen dating violence

Coaching Boys Into Men (CBIM), a program that seeks to reduce dating violence and sexual assault, is effective in discouraging teen dating violence and abusive behaviors, according to a study published online that will appear in the April issue of The Journal of Adolescent Health.

The CBIM program trains high school coaches to use a coaches’ kit of training cards that offer strategies for opening conversations about dating violence and appropriate attitudes toward women. A key component of the 12-week curriculum is teaching young men that even as bystanders they must speak out when witnessing abuse by adults or peers.

A three-year study of more than 2,000 male athletes in 16 California high schools, led by pediatrics faculty member Elizabeth Miller, confirmed the positive impact of the program. Miller, who conducted the study while a member of the faculty at the University of California-Davis, is chief of the Division of Adolescent Medicine at Children’s Hospital.

“As schools, parents and students grapple with the problem of teen dating violence, our study findings offer hope that prevention programs can work,” said Miller. “The high school male athletes whose coaches delivered this easy-to-implement program reported more positive bystander behaviors, meaning that these boys were more likely to say or do something to stop disrespectful and harmful behaviors toward  girls that they witnessed among their male peers.”

The study was funded by the Centers for Disease Control and Prevention. The Waitt Institute for Violence Prevention funds the CBIM program. The CBIM tools are available for free download at www.coachescorner.org.

Heather A. Anderson, Heather L. McCauley and Maria Catrina D. Virata of the Division of Adolescent Medicine were among the study collaborators.

Gestational diabetes research published

School of Medicine researchers have identified a cell-signaling pathway that plays a key role in increasing insulin secretion during pregnancy and, when blocked, leads to the development of gestational diabetes. Their findings are available online in the American Diabetes Association’s journal Diabetes.

During pregnancy, pancreatic beta cells should expand and produce more insulin to adapt to the needs of the growing baby, said senior investigator Adolfo Garcia-Ocana, a faculty member in the medical school’s Division of Endocrinology and Metabolism. Gestational diabetes — high blood glucose during pregnancy — can result in complications for the woman’s newborn baby.

“Not much was known about the maternal mechanisms that lead to increased beta cell number and function during pregnancy,” Garcia-Ocana said. “But research has shown that high blood glucose in pregnancy can have long-term health consequences for the child, as well as a greater risk of hypertension, type 2 diabetes and high cholesterol for the mother.”

His team began studying a protein called hepatocyte growth factor (HGF), which can be found in the blood at increased levels during pregnancy. The protein interacts with a cell surface receptor called c-MET.

The researchers engineered mice that lacked the c-MET receptor in pancreatic cells and found that their beta cells functioned correctly, keeping blood glucose within normal parameters in adult mice. But when the mice got pregnant, they took on the features of gestational diabetes.

“Mice that didn’t have the c-MET receptor in their pancreas had lower plasma insulin levels, higher blood glucose and impaired ability to regulate glucose levels,” Garcia-Ocana said. “Without the receptor, they couldn’t respond to HGF.” Also, unlike normal healthy pregnant females, these mice didn’t produce more beta cells, had more beta cell death and so had reduced beta cell mass.

“These findings provide the first direct evidence that HGF/c-MET signaling pathway has an important role in maternal beta cell adaptation during pregnancy,” Garcia-Ocana noted. “Perhaps women who have a variation in the HGF gene or in the c-MET receptor are predisposed to developing gestational diabetes because they cannot adequately compensate for the increased insulin demands of pregnancy.”

He and his team plan to explore HGF signaling in pregnant women, which could one day provide a new means of diagnosing, treating or preventing gestational diabetes.

Co-authors from the School of Medicine included Cem Demirci of pediatrics and Laura C. Alonso, Juan C. Alvarez-Perez, Gabriella P. Casinelli, Sara Ernst, Taylor Rosa, Varsha Shridhar, Shelley Valle and Rupangi C. Vasavada of the Division of Endocrinology.

The project was funded by the National Institutes of Health, the American Diabetes Association and the Lawson Wilkins Pediatric Endocrine Society.

Astronomers detect kSZ effect

Pitt physics and astronomy faculty member Arthur Kosowsky has collaborated on research that has detected the movement of distant galaxy clusters via the kinematic Sunyaev-Zel’dovich (kSZ) effect, which has never before been seen.

The paper, by lead author Nick Hand and 56 collaborators from the Atacama Cosmology Telescope and the Baryon Oscillation Spectroscopic Survey projects, has been submitted to the journal Physical Review Letters and is posted on the arXiv preprint database. Hand, a graduate student in astronomy at the University of California-Berkeley, began the research as a student at Princeton.

The kSZ effect could provide astronomers with a more precise tool for understanding the forces behind the universe’s formation and growth, including the enigmatic phenomena of dark energy and dark matter.

Proposed in 1972 by a team of Russian physicists, the kSZ effect results when the hot gas in galaxy clusters distorts the cosmic microwave background radiation — which is the glow of the heat left over from the Big Bang — that fills this universe. Radiation passing through a galaxy cluster moving toward Earth appears hotter by a few millionths of a degree, while radiation passing through a cluster moving away appears slightly cooler.

“Traditional methods of measuring velocities require very precise distance measurements, which is difficult. So, these methods are most useful when objects are closer to Earth,” Hand said. “One of the main advantages of the kSZ effect is that its magnitude is independent of a galaxy cluster’s distance from us, so we can measure the velocity of an object’s motion toward or away from Earth at much larger distances than we can now,” Hand said. “In the future, it can provide an additional statistical check that is independent of our other methods of measuring cosmological parameters and understanding how the universe forms on a larger scale.”

Now that it has been detected, the kSZ effect could measure the velocity of objects in the distant universe, the researchers reported. It could provide insight into the strength of the gravitational forces that pull on galaxy clusters and other bodies. Chief among these forces are the still-hypothetical dark energy and dark matter, which are thought to drive the universe’s expansion and the motions of galaxies. In addition, the strength of the kSZ effect’s signal depends on the distribution of electrons in and around galaxies, making it a useful tool to trace the location of atoms in the nearby universe, which could reveal how galaxies form.

The kSZ effect is so small that it is not visible from the interaction with an individual galaxy cluster with the cosmic microwave background, but it can be detected by compiling signals from several clusters, the researchers discovered.

Pitt’s Kosowsky suggested a particular mathematical average that reflects the slight tendency for pairs of galaxy clusters to move toward each other owing to their mutual gravitational attraction, which made the kSZ effect more apparent in the data.

Pediatric glioma vaccine shows promise

Researchers from Children’s Hospital and the University of Pittsburgh Cancer Institute (UPCI) brain tumor program have demonstrated that peptide vaccines in children with gliomas, the most common type of brain tumor, not only were well-tolerated but also showed evidence of immunological responses. The results of the study were presented recently at the American Association for Cancer Research annual meeting.

The study of 27 children with gliomas was led by Pitt neurosurgery faculty member Ian F. Pollack, chief of pediatric neurosurgery at Children’s Hospital’s Brain Care Institute and co-director of UPCI’s brain tumor program, and pediatrics faculty member Regina I. Jakacki, director of pediatric neuro-oncology.

Each child received serial doses of a peptide vaccine, which stimulates an immune response to a protein fragment that is present on their tumor cells.

“We’ve found that this vaccine is tolerated well with limited systemic toxicity, but we’ve also observed that there are some patients who have immunological responses in the vaccine target in the brain that can cause swelling and transient worsening and, subsequently, some of those children can have very favorable responses,” said Pollack. “We’ve also demonstrated immunological responses in the majority of the kids.”

Children with eligible tumor types received a vaccine targeting glioma-associated antigen (GAA) proteins, including EphA2, IL13Ra2 and survivin, every three weeks, for a total of eight doses.

“These kids, who, for the most part, have intact and very strong immune systems, seem to mount an immune response against the vaccine very effectively at rates that may be even higher, I think, than have been noted in studies in adults,” Pollack said.

Among the 22 cases evaluated, three children had rapidly progressive disease, 15 had stable disease for more than three months, three had sustained partial responses and one had prolonged disease-free status after surgery. An immune response analysis, which was completed in seven children, revealed responses in six children: to IL13Ra2 in five cases, EphA2 in three and survivin in three.

Pollack said, “The fact that we’ve seen tumor shrinkage in children with very high-risk tumors has been extremely encouraging and somewhat surprising.”

The National Institutes of Health and the Pediatric Low-Grade Glioma Initiative funded the study.

Depression prevention efforts needed

Depression prevention strategies show promise for reducing the global burden of depressive disorders, according to a Journal of the American Medical Association Viewpoint column written by Charles F. Reynolds III, a faculty member in psychiatry, neurology and neuroscience at the School of Medicine, and co-authors from the Global Consortium for Depression Prevention.

Depression prevention research and practice have progressed to the point that evidence-supported and cost-effective interventions can be disseminated on a large scale, the authors stated, asserting that full use of evidence-based depression prevention strategies has yet to be realized.

“This gap between what is known and implementation of these strategies requires attention, action and the strengthening of research and dissemination efforts,” said Reynolds, the Viewpoint’s corresponding author.

Depressive disorders erode the quality of life, productivity in the workplace and fulfillment of social and familial roles, contributing as well to a vicious circle of poverty, discrimination and poor mental health in middle- and low-income countries, the authors stated.

“Treatment costs of depression are soaring, but are only a fragment of the costs of reduced productivity due to depression,” said Reynolds, who also directs Pitt’s Center for Late Life Depression Prevention and Treatment Research and the Western Psychiatric Institute and Clinic Advanced Center for Intervention and Services Research for Late-Life Mood Disorders.

Gel responds under pressure

Could robots soon be able to feel?

In a paper published online March 26 in Advanced Functional Materials, a team of researchers from Pitt and Massachusetts Institute of Technology (MIT) demonstrated that a non-oscillating gel can be made to oscillate under pressure. These findings pave the way for the development of a wide range of applications that respond chemically after sensing mechanical stimuli.

A team of Pitt researchers predicted the behavior of Belousov-Zhabotinsky (BZ) gel, a material that was first fabricated in the late 1990s and shown to pulsate in the absence of any external stimuli.

Along with her colleagues, Anna Balazs, Distinguished Professor of Chemical and Petroleum Engineering in Pitt’s Swanson School of Engineering, predicted that BZ gel not previously oscillating could be re-excited by mechanical pressure.

The MIT researchers demonstrated that chemical oscillations can be triggered by mechanically compressing the BZ gel beyond a critical stress. Video of the behavior can be found at http://vvgroup.scripts.mit.edu/WP/?p=1078.

“Think of it like human skin, which can provide signals to the brain that something on the body is deformed or hurt,” said Balazs. “This gel has numerous far-reaching applications, such as artificial skin that could be sensory — a holy grail in robotics.” Balazs said the gel could serve as a small-scale pressure sensor for different vehicles or instruments to see whether they’d been bumped, providing diagnostics for the impact on surfaces.

Other Pitt authors were Olga Kuksenok and Victor Yashin of chemical and petroleum engineering.

The research was funded by the National Science Foundation and the U.S. Army.

Roundup morphs tadpoles

The world’s most popular weed killer, Roundup, can cause amphibians to change shape, according to research published recently in Ecological Applications. Biological sciences faculty member Rick Relyea, director of Pitt’s Pymatuning Laboratory of Ecology, demonstrated that sub-lethal and environmentally relevant concentrations of Roundup caused two species of amphibians to alter their morphology.

For the study Relyea set up large outdoor water tanks that contained many of the components of natural wetlands. Some tanks contained caged predators, which emit chemicals that naturally induce changes in tadpole morphology (such as larger tails to aid escape). After adding tadpoles to each tank, he exposed them to a range of Roundup concentrations. After three weeks, the tadpoles were removed from the tanks.

“It was not surprising to see that the smell of predators in the water induced larger tadpole tails,” said Relyea. “That is a normal, adaptive response. What shocked us was that the Roundup induced the same changes. Moreover, the combination of predators and Roundup caused the tail changes to be twice as large.” Because tadpoles alter their body shape to match their environment, having a body shape that does not fit the environment can put the animals at a disadvantage.

Predators cause tadpoles to change shape by altering the stress hormones of tadpoles, said Relyea. The similar shape changes when exposed to Roundup suggest that the weed killer may interfere with the hormones of tadpoles and potentially many other animals.

“This discovery highlights the fact that pesticides, which are important for crop production and human health, can have unintended consequences for species that are not the pesticide’s target,” said Relyea.

“Herbicides are not designed to affect animals, but we are learning that they can have a wide range of surprising effects by altering how hormones work in the bodies of animals. This is important because amphibians not only serve as a barometer of the ecosystem’s health, but also as an indicator of potential dangers to other species in the food chain, including humans.”

Chem research earns NSF CAREER award

Chemistry faculty member W. Seth Horne has received a National Science Foundation (NSF) CAREER award based on his proposal entitled “Supramolecular Light-Harvesting Materials From Self-Assembly of Bio-Inspired Macromolecules.”

The five-year $100,000 grant will fund Horne’s research on the development of new materials that mimic light-harvesting functions of natural photosynthetic proteins. The fundamental principles elucidated in the course of these efforts will be the foundation of a general strategy for the design and construction of protein-based supramolecular assemblies. Moreover, the light-harvesting materials will provide a model system for the study and mimicry of the energy delocalization involved in photosynthesis.

The NSF program supports junior faculty who exemplify the role of teacher-scholars through the integration of education and research.

Synthetic platform for biomaterials developed

A Pitt research team has developed a synthetic platform that shows promise for producing biodegradable materials for biomedical applications. The findings were published online in the March 30 issue of Advanced Functional Materials.

A team led by principal investigator Yadong Wang, a faculty member in the Swanson School of Engineering and the School of Medicine’s Department of Surgery, developed the platform using polymerization between acid and epoxide.

“For the first time, we present a polymerization approach that is very practical and includes a wide range of starting materials, simple synthesis and easy modifications,” said Wang. “This platform shows promise in the advancement of tissue engineering and drug delivery and could produce a variety of biodegradable and functionalized biomaterials.”

Wang and his team set out to address previous barriers regarding synthetics by designing a simple and versatile platform that yields functionalized polyesters with diverse physical, chemical, mechanical and biological properties. More specifically, they focused on hydroxyl groups, a substructure of the water molecule.

While using epoxides for another project, Yang and Pitt postdoctoral student Zhengwei You speculated as to what reaction might occur between acids and epoxides.

The result was a versatile synthetic platform with easy-to-produce capabilities.

In addition to possessing biomedical applications, this type of functionalized polyester will enrich the current collection of compostable polyesters, which, Wang noted, comprise the most promising class of eco-friendly materials.

Funding was provided by the U.S. Department of Defense.

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