Scholarship & Creative Work
Occupational therapy gets people with osteoarthritis moving

Physical activity is the cornerstone of any healthy lifestyle, especially for people with osteoarthritis. Exercise helps to maintain good joint health, manage their symptoms and prevent functional decline. Osteoarthritis often makes physical activity such as exercise and other daily activities a challenge.

An occupational therapist-led approach called activity strategy training could provide patients with knee and hip osteoarthritis the opportunity to lead more active lives and improve their overall health, a study led by researchers at U-M Health System finds.

Researchers found that patients who engaged in activity strategy training along with regular exercise increased their physical activity more than patients who only took part in exercise and health education sessions. Study results are online and set to appear in the October issue of Arthritis & Rheumatism.

"Occupational therapy is really the missing link in promoting wellness of people with hip and knee osteoarthritis," says study lead author Susan Murphy, assistant professor at the Medical School and research health science specialist at the VA Ann Arbor Healthcare System.

The structured rehabilitation program is designed to educate patients about joint protection, proper body mechanics, activity pacing and environmental barriers. For example, patients with joint pain caused by osteoarthritis learn techniques for walking around the house or outdoors, or even getting in and out of a car.

Murphy encourages patients with hip or knee osteoarthritis to seek out opportunities now to enhance and expand their daily physical activity, and improve overall health behaviors.

"People with osteoarthritis tend to know more about surgical options, and less about how they can take an active role in promoting their own health and well-being," Murphy says. "People with osteoarthritis need to be their own agents of change."

Gun shows do not increase homicides or suicides

A new study finds no evidence that gun shows lead to substantial increases in either gun-related homicides or suicides.

The U-M and University of Maryland study also shows that tighter regulation of gun shows does not appear to reduce the number of firearms-related deaths.

"We believe that this analysis makes an important contribution to understanding the influence of gun shows, the regulation of which is arguably the most active area of federal, state, and local firearms policy," says Brian Jacob, a professor at the Gerald R. Ford School of Public Policy and director of the Center for Local, State, and Urban Policy.

"To our knowledge, this is the first study that directly examines the impact of gun shows on gun-related deaths."

The researchers analyzed data from Texas and California, chosen because they are the nation's two most populated states, have large numbers of gun shows, and are at opposite ends of the spectrum regarding regulation. California has some of the most aggressive gun show regulations, including background checks for all purchasers and a 10-day waiting period to obtain the firearm. Texas has no similar regulations.

Data came from the dates and locations of more than 3,400 gun shows, and firearm-related deaths from 1994-2004. More than 105,000 homicides and suicides were reported in the two states during the 11-year period.

To read the full paper go to

Computer hardware 'guardians' protect users from bugs

As computer processor chips grow faster and more complex, they are likely to reach consumers with more design bugs. U-M researchers have devised a system that lets chips work around all functional flaws, even those that are undetected.

The only other solution companies have for this problem is replacing hardware completely.

The researchers' system would eliminate this risk of failure by preventing a chip from operating in untested configurations. The approach keeps track of all the configurations the firm tested, and loads that information onto a miniscule monitor that would be added to each processor. The monitor would treat all untested configurations as potential threats, and proceed in safe mode in order to minimize the risks.

"Users wouldn't even notice when their processor switched to safe mode," says Valeria Bertacco, assistant professor in the Department of Electrical Engineering and Computer Science (EECS). "It would happen infrequently, and it would only last momentarily, to get the computer through the uncharted territory. Then the chip would flip back to its regular mode."

This system could also protect against what could be hackers' next frontier: exploiting hardware design bugs in order to gain control of other computers.

"Semantic guardians would stop these security attackers dead in their tracks, since the processor would no longer be able to execute the buggy configurations that they were planning to exploit," says Ilya Wagner, a doctoral student at EECS.

Wagner presented this research Sept. 29 at the Gigascale System Research Center annual meeting, where industry and government funding agencies come together to learn about new research results.

Traumatic brain injury to troubled teens associated with mental problems

Nearly one out of five delinquent youths suffer from traumatic brain injury (TBI), which can contribute to wide-ranging mental illnesses, new research shows.

These troubled teens had a significantly earlier onset of criminal and substance-using behaviors, and more lifetime substance abuse problems and suicidal tendencies than youths without TBI, says Brian Perron, assistant professor in the School of Social Work.

TBI involves sustaining a head injury causing unconsciousness for more than 20 minutes. The findings also suggest that fights and other assaults may have been a significant source of these injuries.

The researchers used interviews from 720 residents in Missouri rehabilitation facilities. Their ages ranged from 11-20, and 87 percent of the sample were male. Of this group, 132 teens reported a TBI.

Respondents with the brain injury were more likely than their counterparts without it to have used heroin (11 percent versus 5 percent), cocaine or crack cocaine (36 percent versus 21 percent), marijuana (93 percent versus 85 percent) and ecstasy (33 percent versus 17 percent).

When including demographic factors, the research indicates that boys were at higher risks for TBI than girls.

Researchers say the study did not assess the severity of the brain injury or treatment received following it.

"Thus, some youth with more severe TBI and unmet treatment need may have greater functional impairments than the overall trends suggest," Perron says.

The findings appear in current issue of Criminal Behavior and Mental Health.

Research shows why metal alloys degrade

Metal alloys can fail unexpectedly in a wide range of products — from jet engines to satellites to cell phones — and new research from U-M helps to explain why.

Metal alloys are solids made from at least two different metallic elements. The elements are often mixed together as liquid, and when they "freeze" into solids tiny grains of crystal form to create a polycrystalline material.

Atoms within the grains of crystal are arranged in a pattern that is imperfect and includes vacancies. Atoms take advantage of these vacancies in a process called diffusion, when atoms hop through the material and change its structure.

"It's kind of like musical chairs," says Katsuyo Thornton, assistant professor in the Department of Materials Science and Engineering (MSE). "Diffusion happens in nearly every material, and materials can degrade because diffusion causes certain changes in the structure of the material."

Atoms of different elements tend to hop at different rates because they are bound to their surrounding atoms with varying strength. Thornton and her colleagues demonstrated that when there's a greater discrepancy in the hop rates in the different elements in the alloy, there's a more pronounced diffusion along grain boundaries. This possibly leads to a faster degradation.

This finding suggests that materials scientists could make longer-lasting alloys if they use metals with similar atomic hop rates, or manipulate the intrinsic hop rates by other mechanisms.

Thornton's collaborators on this project are Hui-Chia Yu, MSE doctoral student, and Anton Van der Ven, an assistant professor in the same department.

A paper on the findings called "Theory of grain boundary diffusion induced by the Kirkendall effect" is published online in Applied Physics Letters.