Physical Activity Reduces Risk Of Hypertension In Young Adults

Young adults who spend more time participating in physical activity have a reduced risk of developing high blood pressure within the next 15 years, according to researchers at the University of Minnesota.

Research published in the April 2007 issue of the American Journal of Public Health found that young adults who exercised an average of five times a week and expended 300 calories per exercise session experienced a 17 percent reduction in the risk of developing hypertension.

In addition, study participants who maintained or increased their total time participating in physical activity from the start of the study to the finish decreased their risk of high blood pressure by 11 percent for every 1,500 calories they burned weekly.

"This study is the first of its kind to examine the link between physical activity and hypertension in young adults," said David Jacobs, Ph.D., study co-author and professor of epidemiology and community health at the University of Minnesota School of Public Health. "The study further confirms evidence that physical activity is related to hypertension."

Jacobs and colleague Emily Parker, lead author of the study and doctoral student at the University of Minnesota School of Public Health, analyzed data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, which tracked physical activity and measured blood pressure levels in nearly 4,000 men and women over a 15-year period.

Overall, 634 adults developed cases of hypertension over the 15 years of follow-up. After adjusting for race, age, sex, education, and family history, data showed that those participants who were more physically active experienced a reduced risk for hypertension compared with those who were less physically active. "This study shows that physical activity should be considered in the prevention of hypertension in young adults," said Jacobs. "This link gives people another reason to increase their levels of exercise and remain physically active."

Source: University of Minnesota

Stress causes cancer development

U.S. medical scientists have discovered the stress hormone epinephrine makes prostate and breast cancer cells resistant to cell death.

Researchers at the Wake Forest University School of Medicine said they are the first to report that emotional stress might contribute to the development of cancer and might also reduce the effectiveness of cancer treatments.

The study, led by Dr. George Kulik, an assistant professor of cancer biology, was designed to determine whether there is a direct link between stress hormones and changes in cancer cells.

"Population studies have had contradictory results," said Kulik. "We asked the question: 'If stress is linked to cancer, what is the cellular mechanism?' There had been no evidence that stress directly changes cancer cells."

Kulik said the study's findings have several implications for patients and for researchers.

"It may be important for patients who have increased responses to stress to learn to manage the effects," said Kulik. "And, the results point to the possibility of developing an intervention to block the effects of epinephrine."

Scientists study social memory formation

A team of Canadian and French scientists has identified the internal part of the prefrontal cortex as key to memorizing social information.

Researchers from Canada's McGill University and France's University of Paris used a functional magnetic resonance imaging technique to measure cerebral activity in 17 volunteers while they accomplished a memory task involving pictures of social scenes (interacting individuals) and non-social scenes (landscapes with no people).

The researchers identified the medial prefrontal cortex as being the key structure in memorizing social information from a picture.

The scientists said that finding opens important perspectives regarding our understanding of the mechanisms of human recollections and mental disorders such as schizophrenia and autism that affect social and relational skills.

Holding Eye Contact Is Critical When Police Confront Hysterical Citizens

Holding eye contact, or “gaze,” with hysterical citizens is one of the most effective methods police officers can use to calm them down, according to new research conducted by the University of New Hampshire that relies on footage of the FOX TV show “COPS.”

The study by Mardi Kidwell, assistant professor of communication, “’Calm Down!’: the role of gaze in the interactional management of hysteria by the police,” was published recently in Discourse Studies.

According to Kidwell’s research, regulating gaze is central to face-to-face interaction. For police officers, it’s an important factor in gaining compliance from and calming hysterical citizens.

“A great deal of police work involves encountering people who are in crisis, people who are distraught, agitated and sometimes hysterical over the circumstances that have necessitated a police response. Moreover, as police departments nationwide transition from a more traditional model of policing, with its emphasis on catching law-breakers, to a model of community policing, with its emphasis on prevention, they have sought to adapt more humanistic, more dialogic approaches to their communications with citizens,” Kidwell says.

Kidwell’s research relies on police-citizen interactions obtained from the FOX TV show “COPS,” now in its 19th season. She used footage from “COPS” because most research on police-citizen interaction does not rely on a real-time, in-the-moment unfolding of events. In addition, police departments are reluctant to provide footage of their police-citizen interactions.

In the “COPS” segment discussed in the study, two police officers are trying to calm down a woman whose grandson has been shot. The six-minute segment shows the officers arriving on the scene of the shooting, inspecting the victim, questioning witnesses, discussing the case with other officers and, finally, seeking to calm the victim’s grandmother, who herself has been shot at.

The officers are forced to use increasingly stronger verbal tactics – called directives – to get the woman to look at them as they try to calm her down. The woman repeatedly looks at the officers and then looks away, and continues to be hysterical. Finally, one officer gently touches the woman’s face and turns it toward him, forcing her to look at him. Eventually, the officers are able to keep eye contact with her long enough so as to calm her down, help her regain a normal breathing pattern and compose herself so she can drive to the hospital to see her grandson.

Kidwell has found that officers treat citizens’ (usually suspects’) refusal to gaze at them as resistance, and they will continue to pursue the citizens’ gaze in order to gain compliance. “In situations of someone’s extreme distraught-ness, refusal to gaze is associated with being ‘out of it.’ In other words, with being unable to attend to, or participate in, in any normal or competent way current interactional activities,” she says.

Kidwell analyzed more than 35 hours off footage and hundreds of police-citizen interactions as part of her research. She found that police rely on holding gaze to calm individuals in a number of situations, including getting them to cooperate during questioning, keeping them from interfering with emergency workers, and gaining their compliance during arrests.

“There is another, perhaps less institutionally obvious responsibility that the officers are undertaking in this case. This is a responsibility that has to do with being a ‘helper,’ here, specifically with emotional work. This case and others that involve, for example, a small child whose parents have been arrested and a woman who has been abused by her husband, demonstrate that police responsibilities also include simply soothing people who are in crisis and trying to ameliorate their emotional suffering,” Kidwell says.

Source:University of New Hampshire

Futuristic Robot Adapts To People, New Places

In the futuristic cartoon series "The Jetsons," a robotic maid named Rosie whizzed around the Jetsons' home doing household chores--cleaning, cooking dinner and washing dishes.

Such a vision of robotic housekeeping is likely decades away from becoming reality. But at MIT, researchers are working on a very early version of such intelligent, robotic helpers--a humanoid called Domo who grasp objects and place them on shelves or counters.

A robot like Domo could help elderly or wheelchair-bound people with simple household tasks like putting away dishes. Other potential applications include agriculture, space travel and assisting workers on an assembly line, says Aaron Edsinger, an MIT postdoctoral associate who has been working on Domo for the last three years.

Edsinger describes Domo as the "next generation" of earlier robots built at MIT--Kismet, which was designed to interact with humans, and Cog, which could learn to manipulate unknown objects. Domo incorporates elements of both of those robots.

"The real potential of robots in the future is going to be realized when they can do many types of manual tasks," including those that require interaction with humans, Edsinger said. There are now plenty of robots doing manual work on factory assembly lines, but those machines follow a script and can't learn to adapt to new situations, as Domo can, said Rodney Brooks, director of MIT's Computer Science and Artificial Intelligence Laboratory.

"Robots in an automobile factory manipulate objects, but they do the same thing, along the same path, every time," Brooks said. "If robots are ever going to be truly useful, they need to be able to manipulate the objects we manipulate."

Living in the real world
Edsinger's team, overseen by Brooks, decided to focus on making a robot that can function in a real human environment--in someone's kitchen, for example. Robots that are designed to help people in their homes will have to be able to ignore the clutter found in most environments and focus only on certain stimuli, says Edsinger.

"Typically robots are placed in very restricted worlds because then you can control the environment. If you put a robot in someone's home, that approach just doesn't extend to that," he said. "We want the robot to adapt to the world, not the world to adapt to the robot."

Perched on a table in Edsinger's workspace, Domo can "see" everything going on in front of it. As the robot's large blue eyes roam across the room, cameras feed information to 12 computers that analyze the input and decide what to focus on.

Domo's visual system is attuned to unexpected motion, allowing it to focus on important stimuli within human environments. For example, locating human faces is critical for social interaction, and people are often in motion. When Domo spots motion that looks like a face, it locks its gaze onto it.

Edsinger recently demonstrated how Domo can interact with people to help them accomplish useful tasks.

Once he captures Domo's gaze, they exchange greetings. "Hey, Domo," Edsinger says, to which Domo responds, "Hey, Domo." "Shelf, Domo," says Edsinger, prompting the robot to find a shelf. Domo looks around until it spots a nearby table that looks promising. The robot reaches out its left hand to touch the shelf, much like a person groping for a light switch in the dark, to make sure the shelf is really there.

Once Domo has located the shelf, it reaches out its right hand towards Edsinger, who places a bag of coffee beans in the open hand. Domo wiggles them a little to get a feel for the object, then transfers the bag from its right hand to its left hand (nearest the shelf). Domo then reaches up and places the bag on the shelf.

Though it seems like a minor movement, wiggling the object is key to the robot's ability to accurately place it on a shelf, Edsinger says. Domo is programmed to learn about the size of an object by focusing on the tip of the object, for example, the cap of a water bottle. When the robot wiggles the tip back and forth, it can figure out how big the bottle is and decide how to transfer it from hand to hand or to place it on a shelf.

"You can hand it an object it's never seen before, and it can find the tip and start to control it," Edsinger said.

The human connection
The philosophy behind the team's approach is that humans and robots can work together to accomplish tasks that neither could do all alone.

"If you can offload some parts of the process and let the robot handle the manual skills, that is a nice synergistic relationship," Edsinger said. "The key is that it has to be more useful or valuable than the effort put into it."

For Domo or any robot to safely interact with humans, the robot has to be able to sense when a human is touching it. Domo has springs in its arms, hands and neck that can sense force and respond to it. If you grab its hand and push, the robot will move the way you want it to.

"By placing that spring in there, you get physical compliance that makes the whole body sort of springy, which makes it safer for human interaction," Edsinger said. But if you apply too much force or move Domo's arms in the wrong direction, it voices its displeasure by saying "ouch."

If robots are going to be useful in the home, it's also important for them to have a humanoid form, so people will feel more comfortable around them.

Such assistive robots could be very useful in finding solutions to the impending health care crisis caused by the aging of the baby boomers, Edsinger said. Having help with simple tasks, such as getting a glass from a cabinet, could make a big difference for elderly or wheelchair-bound people.

The original work on Domo was funded by NASA, and the project is now supported by Toyota, which is interested in developing partner robots for the home. Another application is in assembly line production. The idea is that intelligent robots could work together with people to make workers more productive and save manufacturing jobs from being sent overseas, says Edsinger.

Although a life of leisure enabled by robots who perform all manual labor is still securely in the realm of science fiction, Brooks says he can foresee a future where robots specialized for different functions help out with household chores.

"I don't think there's going to be one Rosie the robot doing everything in the home," said Brooks. "It's more likely to be a team of robots doing different things."

Source: Massachusetts Institute of Technology

School Bullying Affects Majority Of Elementary Students

Nine out of 10 elementary students have been bullied by their peers, according to a simple questionnaire developed by researchers at Lucile Packard Children's Hospital and the Stanford University School of Medicine. What's more, nearly six in 10 children surveyed in the preliminary study reported participating in some type of bullying themselves in the past year.

The survey explored two forms of bullying: direct, such as threatening physical harm, and indirect, such as excluding someone or spreading rumors. The researchers say the five-minute questionnaire is the first simple, reliable way for teachers and physicians to identify kids at risk and to measure the success of interventions aimed at reducing bullying in schools.

"We know that both bullies and victims tend to suffer higher levels of depression and other mental health problems throughout their lives," said child psychiatrist Tom Tarshis, MD, lead author of the study. "We need to change the perception that bullying at school is a part of life and that victims just need to toughen up."

Tarshis was completing a fellowship in child psychiatry and research at Packard Children's at the time he developed the questionnaire. He is currently the director of the Bay Area Children's Association. The research will be published in the April issue of the Journal of Developmental and Behavioral Pediatrics.

"When I first started to study this subject, there was no real questionnaire that had been tested," said Tarshis. "We couldn't take the next step until we had a tool that we knew worked."

Although the classic definition of bullying brings to mind fistfights in the schoolyard, other more subtle forms of torment also were surveyed. Tarshis recounted a girl in the ninth grade whose friends decided to stop speaking to her, spread nasty rumors about her and exclude her from activities, all right under the nose of an unsuspecting teacher.

"It was a little distressing how prevalent the problem is even in the middle- to upper-middle-class schools we surveyed," said Tarshis.

He and his co-author, Lynne Huffman, MD, associate professor of pediatrics and of psychiatry at the School of Medicine, surveyed 270 children in grades three through six in two schools in California and one in Arizona to determine if the 22-item questionnaire yielded statistically accurate results. Students were scored based on their responses - never, sometimes or often - to such statements as, "At recess I play by myself," "Other students ignore me on purpose," and "Other students leave me out of games on purpose."

Tarshis and Huffman then compared the results to those of other, more complicated surveys intended to identify bullies and victims. They also administered their survey twice to 175 of the students to determine if the results were consistent over time. They found that the responses were highly reliable, and the survey was easily understood and completed by even the youngest students in the sample.

"We found it particularly interesting that these indications of victimization and bullying are apparent at very young ages," said Huffman. "Our hope is that this questionnaire will be utilized by teachers, pediatricians and even child psychiatrists to identify those children needing early and direct intervention."

The stakes are high. Previous research has shown that, without intervention, bullying behavior persists over time: a child who is a bully in kindergarten is often a bully in elementary school, high school and beyond. Such behaviors are not without consequence, though. These career bullies are not only slightly more likely than their peers to serve prison time as adults, they also tend to suffer from depression.

Perhaps not surprisingly, kids who are routinely victimized exhibit higher levels of depression, anxiety and suicidal thoughts than do non-victims. Such statistics highlight the importance of being able to identify at-risk kids and assess the effectiveness of interventions.

Efforts to stop school bullying have been gathering steam for several years. Those most likely to be effective, according to Tarshis, promote an attitude change from the principal to the recess monitors to the parents. They range from presentations to entire schools to discussions with individual students about how to respond when they are bullied or when they see someone bullying another student.

"Positive peer pressure is an important component of effective intervention," said Tarshis. "When uninvolved students step up and let the perpetrator know that their behavior is not acceptable, it's a powerful message."

Source:Stanford University Medical Center

Music players can cause hearing loss

Portable music players can damage your hearing, recent research suggests. Many players can reach potentially damaging volumes, and many users may habitually be cranking the sound up that high.

In a study published in December 2004, Brian J. Fligor, Sc.D., and L. Clarke Cox, Ph.D., at Boston University measured the volume levels of six portable CD players, through both the original headsets, if any, and five others purchased separately. At their highest settings, most of the 35 possible player-headset combinations were loud enough to cause irreversible noise-induced hearing loss if used regularly for as little as a few minutes per day.

The measurements were done shortly before iPods became popular. Fligor, now director of diagnostic audiology at Children's Hospital Boston, said preliminary results indicate that the volumes produced by iPods and other MP3 players are "in the same ballpark" as that of the CD players.

In a separate study published in April 2005, Warwick Williams of Australia's National Acoustic Laboratories measured the noise emanating from the personal music players of 55 randomly chosen passers-by in two busy city intersections. The volume averaged about 86 decibels--a bit too high, say Consumer Reports' noise experts, for extended daily listening. Some players were turned up much higher than that.

At maximum volume with the included headphone, nearly all the MP3 players we rated exceeded 85 decibels in our tests at an external lab, and some exceeded 100, a level that can damage hearing even after short periods of time. To avoid hearing loss, our experts say you should never set your music player's volume higher than 85 decibels, about the same level as a vacuum cleaner or a noisy restaurant. Be sure to judge the volume conservatively: Music you like tends to sound softer than an annoying sound with the same decibel level.

Many players in our MP3 Ratings (available to subscribers) have built-in volume limiters that take the guesswork out of safe listening. Some models have a preset safety level, which can be activated via the player's menu or an on/off switch. All iPods and some Creative models allow you to custom-set the volume limit, as well as protect the setting with a pass code--a nice touch for concerned parents. We recommend setting the maximum volume between 1/2 and 3/4 of the volume bar's full setting. But be aware that the loudness of individual songs can vary significantly, depending upon genre, equalizer setting, and how the song was recorded.

people whose living and working environments are otherwise quiet can safely listen to 85-decibel music for several hours a day. But if you're regularly exposed to other loud sound--whether from machinery, transportation, or live music--you should wear hearing protection at those times if you want to enjoy music from your portable player at other times. That's because damage from noise exposure is cumulative. If you have any concerns about hearing loss, see an audiologist soon.