Insect cyborgs may become first responders, search and monitor hazardous environs
Research conducted at the College of Engineering may lead to the use of insects to monitor hazardous situations before sending in humans. Khalil Najafi, the Schlumberger Professor of Engineering, Arthur F. Thurnau Professor, professor of electrical engineering and computer science, professor of biomedical engineering and chair of Electrical and Computer Engineering, and doctoral student Erkan Aktakka are finding ways to harvest energy from insects, and take the utility of the miniature cyborgs to the next level.
“Through energy scavenging, we could potentially power cameras, microphones and other sensors and communications equipment that an insect could carry aboard a tiny backpack,” Najafi says. “We could then send these ‘bugged’ bugs into dangerous or enclosed environments where we would not want humans to go.”
The principle idea is to harvest the insect’s biological energy from either its body heat or movements. The device converts the kinetic energy from wing movements of the insect into electricity, thus prolonging the battery life. The battery can be used to power small sensors implanted on the insect (such as a small camera, a microphone, or a gas sensor) in order to gather vital information from hazardous environments.
A spiral piezoelectric generator was designed to maximize the power output by employing a compliant structure in a limited area. The technology developed to fabricate this prototype includes a process to machine high-aspect ratio devices from bulk piezoelectric substrates with minimum damage to the material using a femtosecond laser.
In a paper called “Energy scavenging from insect flight” (recently published in the Journal of Micromechanics and Microengineering) the team describes several techniques to scavenge energy from wing motion and presents data on measured power from beetles.
— Matt Nixon, College of Engineering
U-M researchers find genetic rearrangements driving 5 to 7 percent of breast cancers
Researchers at the Comprehensive Cancer Center have discovered two cancer-spurring gene rearrangements that may trigger 5 to 7 percent of all breast cancers.
These types of genetic recombinations have previously been linked to blood cancers and rare soft-tissue tumors, but are beginning to be discovered in common solid tumors, including a large subset of prostate cancers and some lung cancers.
Looking at the genetic sequencing of 89 breast cancer cell lines and tumors, researchers found two distinct types of genetic rearrangements that appear to be driving this subset of breast cancers. The recurrent patterns were seen in the MAST kinase and Notch family genes. The findings were published online in Nature Medicine ahead of print publication.
“What’s exciting is that these gene fusions and rearrangements can give us targets for potential therapies,” says Dr. Arul Chinnaiyan, director of the Michigan Center for Translational Pathology, Howard Hughes Medical Institute Investigator, and S.P. Hicks Professor of Pathology at the Medical School. “This is a great example of why treating cancer is so challenging. There are so many different ways genes get recombined and so many molecular subtypes, that there’s not one solution that will work for all of them.”
The discoveries illuminate a promising path for future research, Chinnaiyan says. Gene sequencing offers opportunities to develop treatments for individuals whose tumors carry specific genetic combinations – a process commonly known as “personalized medicine.”
Additional U-M authors are Dan R. Robinson, Shanker Kalyana-Sundaram, Yi-Mi Wu, Sunita Shankar, Xuhong Cao, Bushra Ateeq, Irfan Asangani, Matthew Iyer, Christopher Maher, Catherine Grasso, Robert Lonigro, Michael Quist, Javed Siddiqui, Rohit Mehra, Xiaojun Jing, Thomas Giordano, Michael Sabel, Celina Kleer, Nallasivam Palanisamy and Chandan Kumar-Sinha.
— Ian Demsky, UMHS Public Relations
Researchers watch a next-gen memory bit switch in real time
For the first time, engineering researchers have been able to watch in real time the nanoscale process of a ferroelectric memory bit switching between the 0 and 1 states.
Ferroelectric materials have the potential to replace current memory designs, offering greater storage capacity than magnetic hard drives and faster write speed and longer lifetimes than flash memory. Replacing dynamic random access memory — the short-term memory that allows your computer to operate — with ferroelectric memory can significantly decrease energy usage in computers. Ferroelectric memory doesn’t require power to retain data.
A paper on the research was published in the Nov. 18 edition of Science.
“This is a direct visualization of the operation of ferroelectric memory,” says principal investigator Xiaoqing Pan, a professor in the Department of Materials Science and Engineering and director of the U-M Electron Microbeam Analysis Laboratory.
“By following ferroelectric switching at this scale in real time, we’ve been able to observe new and unexpected phenomena. This work will help us understand how these systems work so one can make better memory devices that are faster, smaller and more reliable.”
The researchers were able to see that the switching process of ferroelectric memory begins at a different site in the material than they initially believed. And this switching can be sparked with a lot less power than they had hypothesized.
“In this system, electric fields are naturally formed at the ferroelectric/electrode interfaces and this lowers the barrier for switching — for free. That means you can write information with much lower power consumption,” Pan says.
Pan is leading the development of special hybrid materials that contain both ferroelectric and magnetic components and could lead to next-generation magnetoelectric memory devices.
— Nicole Casal Moore, News Service
Poll: Pennsylvania citizens doubt media, environmentalists, scientists, governor in ‘fracking’ debate
Pennsylvanians have significant doubts about the credibility of the media, environmental groups and scientists on the issue of natural gas drilling using “fracking” methods, a new poll says.
Those surveyed also believe the state’s governor, Tom Corbett, is too closely aligned with companies involved in fracking in Pennsylvania, which is on the frontline of a growing national and international debate about the industry.
The findings raise serious questions about where Pennsylvanians should seek credible information and leadership on an issue that is becoming increasingly important to the state’s economy and environment.
The poll, one of the most extensive recent surveys on fracking, was conducted by the Muhlenberg Institute of Public Opinion in collaboration with the Gerald R. Ford School of Public Policy.
Although fracking has been done for decades in several states, the process has become more popular in recent years, raising concerns about safety and the environment. Fracking is common in Oklahoma, Texas, New York, Wyoming and Alaska as well as in Canada and Britain.
The process involves injecting water and chemicals deep into the ground. This fractures rock structures and provides access to vast natural gas deposits.
Some have suspicions about the chemicals used and worry about possible groundwater contamination. The Muhlenberg/Michigan poll found that 84 percent of those surveyed strongly agreed that drilling companies should have to disclose the chemicals used in fracking.
There was also distrust in the government, with 60 percent saying they either strongly or somewhat agreed that natural gas companies have too much influence on Corbett’s decisions about regulating drilling. Only 14 percent say they strongly or somewhat agree.
— William Foreman, News Service
‘Perfect black’ coating can render a 3-D object flat
A carbon nanotube coating developed at U-M acts as a “magic black cloth” that conceals an object’s three-dimensional geometry and makes it look like a flat black sheet.
The 70-micron coating, or carbon nanotube carpet, is about half the thickness of a sheet of paper. It absorbs 99.9 percent of the light that hits it, researchers say.
“You could use it to completely hide any 3-D attributes of an object,” says Jay Guo, a professor in the Department of Electrical Engineering and Computer Science and principal investigator.
“It’s not cloaking, as the object can still cast a shadow. But if you put an object on a black background, then with this coating, it could really become invisible.”
A paper on the research is newly published online in Applied Physics Letters.
To demonstrate this concept, the researchers made a raised, microscopic tank shape on a piece of silicon. They then grew the carbon nanotube carpet on top of the entire silicon chip. In photos taken through an optical microscope, they show that the tank is imperceptible. As a control, they did this again, carving out a rectangle that was not coated with carbon nanotubes. The rectangle is visible on this chip, but the tank remains hidden.
The “perfect black” material Guo’s team created for this coating has a host of varied applications. It possibly could be used in display screens for ultra-high contrast and a crisper picture. It holds promise as solar heating device. The National Institute of Standards and Technology is using a similar material to absorb infrared light and measure the amount of heat it can generate.
The coating could inspire a new type of camouflaging paint for stealth aircraft. Today’s stealth planes use shape to scatter electromagnetic waves and avoid detection, and this scheme could actually absorb the waves.
Other co-authors are electrical engineering post-doc Haofei Shi, doctoral student Hyoung Won Baac and mechanical engineering doctoral student Jong Ok.
— Nicole Casal Moore, News Service
Short waits, long consults keep most patients very happy with their physicians
Patients overall in the United States are very satisfied with their physicians and with treatment they receive in outpatient settings, according to new information which challenges common public perceptions about outpatient medical treatment.
“Particularly surprising is that even a lot of patients who reported average encounters with physicians, such as average national wait times and average physician encounter time, seem to be giving full marks to their physician in terms of visit satisfaction,” says Rajesh Balkrishnan, lead study author and associate professor in the School of Public Health and College of Pharmacy.
The study analyzed data from an online survey tool, www.DrScore.com, where 14,984 patients ranked visits from 2004-2010 on a 10-point scale, with 10 being the highest. The average overall satisfaction rating was 9.28. Of those, 70 percent, or 10,510 of the scores were 10s. Another 2,291, or 15 percent, were 9s. Less than 2 percent of the ratings were 1 or less, Balkrishnan says.
So why then, is the public perception that people aren’t happy with doctors, who are often too rushed, not engaged, and make them wait too long?
“The few highly publicized cases of dissatisfaction are what is driving common public perception,” Balkrishnan says. “Public perceptions are influenced by various factors, including personal experiences, headline news stories, which are rarely flattering, and media images.”
These high marks overall suggest that most patients give doctors the benefit of the doubt, he says. The majority of patients realize that factors beyond the physician’s control, such as insurance red tape, contribute to their dissatisfaction.
Older patients, those with shorter waiting times and patients who reported spending more time with their physicians had the highest scores. Younger patients, those who reported longer waits and patients who spent less than five minutes with their physicians had the lowest scores.
— Laura Bailey, News Service
Kids in lower-income homes more likely to be obese, have poor health habits
Childhood obesity and the unhealthy behaviors that contribute to weight gain are more likely among children from lower-income households, according to a study by the Cardiovascular Center.
Results of the research were presented last month at the American Heart Association 2011 Scientific Sessions.
Led by U-M researcher Taylor Eagle, the findings are based on analysis of socioeconomic status and body mass index of children in Massachusetts and comparisons between socioeconomic status and health-related behaviors of children in Michigan.
Researchers found that as household income declined, the percent of overweight children increased, as did the incidence of poor diet and exercise behaviors.
“There is a significant relationship between low household income and poorer lifestyle habits,” Eagle says. “Understanding this relationship is critical to curbing the childhood obesity epidemic the U.S. faces today.”
In Massachusetts communities where more than 20 percent of households were low income, the incidence of childhood obesity increased to as much as 35 percent to 45 percent.
Similarly, in Michigan, as household income decreased, daily fried food consumption doubled, daily TV time tripled and vegetable consumption and exercise declined.
These findings were based on the reported habits of 999 sixth graders from four Michigan communities: Ann Arbor, Corunna, Detroit and Ypsilanti.
Michigan children involved in the study participate in Project Healthy Schools, a school-based program supported by communities and the Cardiovascular Center to teach middle school students about healthy lifestyles, in hopes of reducing their future risk of cardiovascular disease and diabetes.
Additional U-M authors are Anne Sheetz, Roopa Gurm, Dr. Alan Woodward, Eva Kline-Rogers, Robert Leibowitz, Jean DuRussel-Weston, LaVaughn Palma-Davis, Susan Aaronson, Catherine Fitzgerald, Lindsey Mitchell, Bruce Rogers, Patricia Bruenger, Katherine Skala, Dr. Caren Goldberg, Dr. Elizabeth A. Jackson, Steven R. Erickson and Dr. Kim Eagle.
— Justin Harris, UMHS Public Relations
Higher rankings lead to less cooperative facial expressions
New U-M research indicates that people in higher-ranked positions tend to exhibit facial expressions that are perceived by others as less cooperative, influencing how others react to them.
“Our studies show that the effects of rank on cooperativeness spill over into the individual’s nonverbal cues, which are not only picked up by observers, but also lead them to act differently towards the individual,” says Patricia Chen, a U-M psychology graduate student and the study’s lead author.
The findings contribute to broader research on rankings, cooperativeness and nonverbal expressions, as well as negotiations, leadership and group dynamics.
In three studies, Chen and colleagues tested the hypothesis that the higher the rank of an individual’s group, the less cooperative the facial expression of that person is judged to be. They showed that these effects occur even when independent evaluators know nothing about the target’s identity, group or actual rankings.
One study examined the effect among top business school deans. Thirty-five U-M undergraduate students and alumni completed an online survey involving cropped photographs of the faces of deans from top business schools at other universities.
Respondents, blind to the actual rankings and identities of the people they rated, viewed these photographs and then reported how cooperative the deans looked. The results showed that the higher the rank of the business school, the less cooperative the dean appeared.
“Leaders need to be aware that their ranking might spill over into their facial expressions when they interact with others in the organization, affecting what others think of their cooperative intentions,” says co-author Christopher Myers, a doctoral student in the Stephen M. Ross School of Business.
Chen and Myers conducted the research with Shirli Kopelman, clinical assistant professor of management and organizations, and Stephen Garcia, associate professor of psychology.
The findings will appear in the forthcoming issue of the Journal of Applied Psychology.
— Jared Wadley, News Service
Illegal backdating: Small firms get a free pass
Smaller companies are more likely than larger firms to commit illegal backdating of executive stock options but are less likely to be punished, U-M researchers say.
“There are numerous instances in the law where small firms have been granted exemptions from regulatory restrictions due to a disproportionate effect on these companies,” says Cindy Schipani, professor of business law at the Stephen M. Ross School of Business. “Our results show that small firms, although not exempted from regulation prohibiting undisclosed backdating and not less culpable than large firms, have been spared the bulk of law enforcement.”
In a new study of more than 6,000 public companies from 2002 to 2005, Schipani and Ross School colleagues M.P. Narayanan and H. Nejat Seyhun, along with Deniz Anginer of the World Bank, estimate nearly 500 firms engaged in illegal backdating during this time, of which about 100 were implicated (investigated or prosecuted).
They found that the average size of all backdating firms as measured by the variable market capitalization was smaller than that of all firms in general ($213 million vs. $284 million). On the other hand, the average size of implicated backdating firms ($1.83 billion) was much greater than that of all firms overall.
“This implies that smaller firms are less likely to comply with regulation, at least in the case of backdating, raising doubts about the wisdom of exempting small firms from regulations or their enforcement,” says Seyhun, professor of finance at the Ross School.
According to the study, which is forthcoming in the New York University Journal of Legislation and Public Policy, firm size, size of compensation and financial performance are all determining factors of whether a company will be investigated or prosecuted for illegal backdating.
— Bernie DeGroat, News Service
New research debunks popular method of paying off debt
Consumers with multiple debts routinely mismanage them, paying off small debts first even when larger debts have higher interest rates, a U-M researcher says.
Although some personal finance experts advocate eliminating smaller debt first — even if it has a lower interest rate — in order to get a quick win, new research from Scott Rick of the Stephen M. Ross School of Business shows that such advice actually makes it harder to dig out of debt.
Debt is a major issue for U.S. consumers, since the average credit user holds more than five credit cards each with an average balance of more than $1,000, not to mention mortgages, car loans, student loans and other debt.
“It really seems like it makes sense when confronted with multiple debts to eliminate one right away,” says Rick, assistant professor of marketing. “But there are more obscure attributes with debt, like interest rates, that make it the wrong thing to do in some cases.”
In an article appearing this month in a special edition of the Journal of Marketing Research, Rick and colleagues devised a series of studies using field surveys and laboratory experiments. Their results show that consumers with multiple debts focus on reducing the total number of outstanding loans rather than on the total debt across loans. This phenomenon is known as “debt account aversion” and it’s a strong bias.
It’s so strong that experimental participants stuck to it even when they were required to acknowledge how much interest they were accumulating.
— Terry Kosdrosky, Stephen M. Ross School of Business
