Wednesday, October 21, 2009

BODY POSTURE AFFECTS CONFIDENCE IN YOUR OWN THOUGHTS

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Sitting up straight in your chair isn’t just good for your posture – it also gives you more confidence in your own thoughts, according to a new study.

Researchers found that people who were told to sit up straight were more likely to believe thoughts they wrote down while in that posture concerning whether they were qualified for a job.

On the other hand, those who were slumped over their desks were less likely to accept these written-down feelings about their own qualifications.

The results show how our body posture can affect not only what others think about us, but also how we think about ourselves, said Richard Petty, co-author of the study and professor of psychology at Ohio State University.

“Most of us were taught that sitting up straight gives a good impression to other people,” Petty said. “But it turns out that our posture can also affect how we think about ourselves. If you sit up straight, you end up convincing yourself by the posture you’re in.”

Petty conducted the study with Pablo Briñol, a former postdoctoral fellow at Ohio State now at the Universidad Autónoma de Madrid in Spain, and Benjamin Wagner, a current graduate student at Ohio State. The research appears in the October 2009 issue of the European Journal of Social Psychology.

The study included 71 students at Ohio State. When they entered the lab for the experiment, the participants were told they would be taking part in two separate studies at the same time, one organized by the business school and one by the arts school.

They were told the arts study was examining factors contributing to people’s acting abilities, in this case, the ability to maintain a specific posture while engaging in other activities. They were seated at a computer terminal and instructed to either “sit up straight” and “push out [their] chest]” or “sit slouched forward” with their “face looking at [their] knees.”

While in one of these positions, students participated in the business study, which supposedly investigated factors contributing to job satisfaction and professional performance.

While holding their posture, students listed either three positive or three negative personal traits relating to future professional performance on the job.

After completing this task, the students took a survey in which they rated themselves on how well they would do as a future professional employee.

The results were striking.

How the students rated themselves as future professionals depended on which posture they held as they wrote the positive or negative traits.

Students who held the upright, confident posture were much more likely to rate themselves in line with the positive or negative traits they wrote down.

In other words, if they wrote positive traits about themselves, they rated themselves more highly, and if they wrote negative traits about themselves, they rated themselves lower.

“Their confident, upright posture gave them more confidence in their own thoughts, whether they were positive or negative,” Petty said.

However, students who assumed the slumped over, less confident posture, didn’t seem convinced by their own thoughts – their ratings didn’t differ much regardless of whether they wrote positive or negative things about themselves.

The end result of this was that when students wrote positive thoughts about themselves, they rated themselves more highly when in the upright than the slouched posture because the upright posture led to confidence in the positive thoughts.

However, when students wrote negative thoughts about themselves, they rated themselves more negatively in the upright than the slouched posture because the upright posture led to more confidence in their negative thoughts.

Petty emphasized that while students were told to sit up straight or to slump down, the researchers did not use the words “confident” or “doubt” in the instructions or gave any indication about how the posture was supposed to make them feel.

In a separate experiment, the researchers repeated the same scenario with a different group of students, but asked them a series of questions afterwards about how they felt during the course of the study.

“These participants didn’t report feeling more confident in the upright position than they did in the slouched position, even though those in the upright position did report more confidence in the thoughts they generated,” Petty said.

That suggests people’s thoughts are influenced by their posture, even though they don’t realize that is what’s happening.

“People assume their confidence is coming from their own thoughts. They don’t realize their posture is affecting how much they believe in what they’re thinking,” he said.

“If they did realize that, posture wouldn’t have such an effect.”

This research extends a 2003 study by Petty and Briñol which found similar results for head nodding. In that case, people had more confidence in thoughts they generated when they nodded their head up and down compared to when they shook their head from side to side.

However, Petty noted that body posture is a static pose compared to head nodding, and probably more natural and easy to use in day-to-day life.

“Sitting up straight is something you can train yourself to do, and it has psychological benefits – as long as you generally have positive thoughts,” he said.

For example, students are often told when taking a multiple-choice test that if they’re not absolutely sure of the answer, their first best guess is more often correct.

“If a student is sitting up straight, he may be more likely to believe his first answer. But if he is slumped down, he may change it and end up not performing as well on the test,” he said.

(Photo: OSU)

Ohio State University

MICRO-GRAVITY A HEALTH HAZARD FOR ASTRONAUTS

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Australian scientists may have pinpointed the cause of muscle wasting and bone-density loss experienced by astronauts who fly lengthy missions under the weightless conditions of space, new research reveals.

University of New South Wales researchers used a NASA rotating-wall vessel to reproduce microgravity, which is experienced by astronauts in low Earth orbit, to analyse its effect on human embryonic stem cells.

Seventy five per cent of the proteins from the cells exposed to microgravity were not found in those grown under normal gravity. The microgravity-exposed cells produced more proteins that negatively regulate bone density and fewer proteins with antioxidant effects. Antioxidants protect the body from reactive oxidants that can damage DNA.

"The finding may explain loss of bone density and muscle wasting experienced by astronauts," says Dr Brendan Burns, a UNSW biologist who led the study with researchers Elizabeth Blaber and Helder Marcal.

"A lot of work has been done on microgravity at a systemic level, such as the effects on the immune system. No-one has really looked at the effect of microgravity at a cellular level and we think that is a huge gap.

"What we've found is a range of different proteins that are potentially important for astronaut health were more or less predominant in terms of different gravity."

NASA has hinted at plans to construct a solar-powered outpost at one the Moon's poles by 2024. The base would permit sustained human presence on the Moon, which would serve as a staging post for future missions to Mars and beyond.

But prolonged exposure to microgravity would pose increased health risks to astronauts. The absence of normal Earth gravity causes physiological changes, such as bone loss, muscle atrophy and loss of blood volume, which could cause astronauts to feel lightheaded and dizzy once they arrive at the surface of Mars after a long voyage.

It has long been known that microgravity affects bone density but so far nobody has pinpointed the genes and proteins that are affected by microgravity which might promote this condition. Research aimed at understanding the effects of microgravity on human physiology could assist the development of health and safety practices for astronauts.

(Photo: UNSW)

University of New South Wales

A SIMPLE WAY FOR MIDDLE AGED AND OLDER ADULTS TO ASSESS HOW STIFF THEIR ARTERIES ARE: REACH FOR THEIR TOES

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How far you can reach beyond your toes from a sitting position – normally used to define the flexibility of a person’s body – may be an indicator of how stiff your arteries are.

A study in the American Journal of Physiology has found that, among people 40 years old and older, performance on the sit-and-reach test could be used to assess the flexibility of the arteries. Because arterial stiffness often precedes cardiovascular disease, the results suggest that this simple test could become a quick measure of an individual’s risk for early mortality from heart attack or stroke.

“Our findings have potentially important clinical implications because trunk flexibility can be easily evaluated,” said one of the authors, Kenta Yamamoto. “This simple test might help to prevent age-related arterial stiffening.”

It is not known why arterial flexibility would be related to the flexibility of the body in middle age and older people. But the authors say that one possibility is that stretching exercises may set into motion physiological reactions that slow down age-related arterial stiffening.

The study “Poor trunk flexibility is associated with arterial stiffening” appears in the American Journal of Physiology – Heart and Circulatory Physiology. The authors are: Kenta Yamamoto of the University of North Texas and the National Institute of Health and Nutrition, Japan; Hiroshi Kawano, Yuko Gando and Mitsuru Higuchi of Waseda University, Japan; Motoyuki Iemitsu of International Pacific University, Japan; Haruka Murakami, Michiya Tanimoto, Yumi Ohmori, Izumi Tabata, Motohiko Miyachi of the National Institute of Health and Nutrition; and Kiyoshi Sanada of Ritsumeikan University, Japan. The American Physiological Society published the study.

Healthy blood vessels are elastic, and elasticity helps to moderate blood pressure. Arterial stiffness increases with age and is a risk factor for cardiovascular disease and death. Previous studies have established that physical fitness can delay age-related arterial stiffness, although exactly how that happens is not understood. The authors noted that people who keep themselves in shape often have a more flexible body, and they hypothesized that a flexible body could be a quick way to determine arterial flexibility.

The researchers studied 526 healthy, non-smoking adults, 20 to 83 years old, with a body mass index of less than 30. They wanted to see whether flexibility of the trunk, as measured with the sit and reach test, is associated with arterial stiffness. The researchers divided the participants into three age groups:

-young (20-39 years old)

-middle aged (40-59 years old)

-older (60-83 years old)

The researchers asked participants to perform a sit-and-reach test. The volunteers sat on the floor, back against the wall, legs straight. They slowly reached their arms forward by bending at the waist. Based on how far they could reach, the researchers classified the participants as either poor- or high-flexibility.

The researchers also measured blood pressure and the speed of a pulse of blood as it flowed through the body. They measured how long the pulse takes to travel between the arm and the ankle and between the neck and the leg. They also measured aortic pressure in some participants and tested the participants for cardiorespiratory fitness, muscular strength and endurance.

The study found that trunk flexibility was a good predictor of artery stiffness among middle age and older participants, but not among the younger group. In middle age and older participants, they also found that systolic blood pressure (the peak pressure that occurs as the heart contracts) was higher in poor-flexibility than in high-flexibility groups.

Why would the flexibility of the body be a good indicator of arterial stiffness? In the study, the authors speculate on why this would be. One possibility is that there is a cause and effect: the stretching exercises that provide flexibility to the body may also slow the age-related stiffening of the arteries. The study found that arterial stiffness among middle age and older people was associated with trunk flexibility but was independent of muscle strength and cardiorespiratory fitness (as measured by performance on an exercycle). In addition, they cited another recent study that found that middle age and older adults who began a regular stretch exercise program significantly improved the flexibility of their carotids, a major artery found in the neck.

“Together with our results, these findings suggest a possibility that improving flexibility induced by the stretching exercise may be capable of modifying age-related arterial stiffening in middle-aged and older adults,” Dr. Yamamoto said. “We believe that flexibility exercise, such as stretching, yoga and Pilates, should be integrated as a new recommendation into the known cardiovascular benefits of regular exercise.”

However, there are other possibilities as to why bodily flexibility should be an indicator of arterial stiffness. One possibility is that it is related to the higher blood pressure that was seen in the poor flexibility group. Another possibility is that the amount of collagen and elastin, which makes the muscles flexible, also makes the arteries flexible. Further research is needed to understand whether there is a cause-effect relationship between flexibility and arterial stiffness, they said.

The American Physiological Society

A WOMAN IN SPACE

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In the early years of the “space race” (1957-1975) two men sought to test a scientifically simple yet culturally complicated theory: that women might be innately better suited for space travel than men.

In 1960 the thought of a woman in space was a radical one, and justifiably so. On the ground 75% of American women did not work outside the home and females were banned from military flight service altogether. In marriage, wives were required to have their husband’s permission to take out a bank loan, buy property, or purchase large household goods such as a refrigerator. Despite the social odds, a Harvard-educated surgeon and a U.S. Air Force General sought to determine if, from a purely practical perspective, women were suitable for space flight.

The latest look at the intersection of physiology, spaceflight and politics is captured in a new article entitled “A Forgotten Moment in Physiology: The Lovelace Woman in Space Program (1960-1962),” written by Kathy Ryan, Jack Loeppky and Donald Kilgore*. Their article appears in the September edition of Advances in Physiology (http://advan.physiology.org/cgi/reprint/33/3/157), a publication of the American Physiological Society (APS; www.the-aps.org/press). The APS has been an integral part of the scientific discovery process since it was founded in 1887.

In 1957, the Union of Soviet Socialist Republics (USSR) launched Sputnik, the first unmanned orbital satellite, thus formalizing the race for space. The following year the U.S. government established the National Aeronautics and Space Administration (NASA) and in April 1959, NASA introduced the seven men who would comprise the first American astronaut group, better known as the Mercury 7 crew. Individually, the Mercury members made six flights between 1961 and 1963 of which two would reach space, defined as 62 miles above earth. In 1962, John Glenn became the first American to orbit the earth.

Sometime before the mid-1950s two men had begun to seriously discuss the possibility of sending a woman rather than a man into space. One of the men was William R. (“Randy”) Lovelace, II, a Harvard-educated physician, surgeon and aeromedical physiologist. During his years at the Mayo Clinic Lovelace co-developed a much-needed high altitude mask that delivered oxygen to pilots while in flight. At the time, aircraft cabins were not pressurized which lead to hypoxia-induced errors and accidents by pilots. Upon leaving Mayo he established the private Lovelace Foundation for Medical Education and Research, which received government contracts throughout the ‘50s to conduct aerospace research. Lovelace was also among the team of experts who developed the physiological, medical and psychological criteria by which astronaut candidates were assessed and selected, including the Mercury 7 team.

General Donald Flickinger, Air Force chief of bioastronautics at the Air Force Air Research and Development Command (ARDC), was a member of the NASA Special Advisory Committee on Life Sciences and a friend and oft-time collaborator with Lovelace. In 1959 Flickinger established the Woman in Space Earliest (WISE) program at ARDC. Thereafter, he and Lovelace began to contemplate plans for testing women in space.

Their proposition was based purely on physiology and practicality. They recognized that women’s lighter weights would reduce the amount of propulsion fuel being used by the rocket’s load and that women would require less auxiliary oxygen than men. They knew that women had fewer heart attacks than men and their reproductive system was thought to be less susceptible to radiation than a male’s. Finally, preliminary data suggested that women could outperform men in enduring cramped spaces and prolonged isolation.

Before WISE testing could begin the Air Force announced that it would no longer pursue the program. In response, Lovelace established a privately funded effort, the Woman in Space Program, in 1959. A total of 19 women were enrolled, most of whom had been selected from flight schools.

The women underwent the identical tests that the male candidates had undergone. In the end, 68% of the women passed with “no medical reservations” compared to 56% of the men. The 13 females who passed were known as the Mercury 13. They were Bernice “Bea” Steadman, Janey Hart, Geraldine “Jerri” Sloan Truhill, Rhea Allison Woltman, Sarah Lee Gorelick Ratley, Jan Dietrich, Marion Dietrich, Myrtle Cagle, Irene Leverton, Gene Nora Jessen, Jean Hixson, Wally Funk and Geraldyn “Jerrie” Cobb.

The data collected from these women from their physiological testing were never published and had apparently been lost. Dr. Loeppky, one of the co-authors of the article, had worked with Dr. Ulrich Luft, an eminent physiologist who had performed the original aerobic exercise capacity tests on both the female and male astronaut candidates. For the first time, the current paper summarizes these physiological data, demonstrating that the aerobic capacities of the top four women were comparable to those of male pilots of the time.

Jerrie Cobb was the first female to volunteer for the program. Having taken up flying at just age 12, she held numerous world aviation records for speed, distance and altitude, and had logged more than 10,000 hours of flight time. Of the Mercury 7 astronauts, John Glenn had the most flight experience at a total of 5,100 hours.

Cobb had undergone a standard battery of personality and intelligence tests, EEG and neurological tests and psychiatric interviews. On the final day of advanced testing she was immersed in a soundproof isolation tank filled with cold water in order to induce total sensory deprivation. Based on previous experiments in several hundred subjects, it was thought that six hours was the absolute limit of tolerance for the experiment before the onset of hallucinations. Cobb, however, spent more than nine hours in the water, before the staff terminated the experiment.

All told, Cobb had tested in the top 2% of all tested candidates, male and female. In May 1961 Cobb received an informal invitation to undergo spaceflight stimulation training at the U.S. Naval School of Aviation Medicine in Pensacola, FL. After ten days of testing, she had scored as well as experienced Navy pilots and plans were made to test the remaining 12 women.

Jackie Cochran was the leading woman in American aviation in 1960. During World War II, she founded and led the Women Airforce Service Pilot (WASP) to fly military aircraft domestically (thus freeing up male pilots for combat service). In 1953, she was the first woman to break the sound barrier. Although she knew of the Woman in Space project, and did not meet the qualifications for testing, she believed she had been deprived of a leadership role in the program. In the end, however, she and her husband agreed to fund the Pensacola testing for the 12 women.

Despite Cochran’s funding and the promising results, the Pensacola testing had not been authorized and the military would not move forward. Lovelace could not pursue the Woman in Space program further. Cobb assumed the de facto leadership of the women and began extensive lobbying efforts. In a meeting with then-Vice President Lyndon Johnson, he expressed no support for the program. Embittered by her experience Jerrie Cobb continued to lobby until 1965. For the next five years she flew missionary operations in the Amazon and in 1980 was nominated for the Nobel Peace Prize for her efforts. It would be more than 30 years after the testing that 11 of the 13 Mercury women would be reunited. This time, 1995, they came to watch Eileen Collins pilot the first flight of the joint Russian-American Space Program.

The vision of Lovelace and Flickinger to launch the Woman in Space Program in 1959 was remarkable not only for the science it attempted to discover, but for the times. The combination of this ingenuity and the capability and willingness of the women in the program ultimately allowed the space program to advance as far as it did.

(Photo: APS)

The American Psysiological Society

NEW STONE CIRCLE DISCOVERED NEAR STONEHENGE

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Archaeologists have discovered evidence of a lost stone circle on the west bank of the River Avon, a mile from Stonehenge.

The new circle, being called ‘Bluestonehenge’, is 10m in diameter and was surrounded by a henge – a ditch with an external bank.

The circle of stones – no longer present – would have marked the end of the Avenue, a 2.8 km processional route that leads from the River Avon to Stonehenge, which was constructed at the end of the Stone Age (the Neolithic period). The outer henge around the stones was built around 2400 BC, but arrowheads found in the circle indicate the stones were erected as much as 500 years earlier.

Excavations in August-September 2009 by the Stonehenge Riverside Project – a consortium of universities including the University of Bristol – uncovered the nine stone holes, part of a circle of probably 25 standing stones. Most of the circle remains unexcavated, preserved for future research, whilst the 2009 excavation has now been filled back in.

The stones from the new-found circle were removed thousands of years ago but the sizes of the holes in which they stood indicate that this was a circle of bluestones that were brought from the Preseli mountains of Wales 150 miles away, like the inner stones at Stonehenge.

When the stones from the newly-discovered circle were removed by Neolithic people, it is possible that they were dragged along the route of the Avenue to Stonehenge, to be incorporated within its major phase of rebuilding around 2500 BC. Archaeologists know that after this date Stonehenge consisted of some 80 Welsh blue stones and 83 local sarsen stones. Some of the bluestones that once stood at the riverside probably now stand within the centre of Stonehenge.

Dr Josh Pollard, from the University of Bristol and co-director of the project, explained: “This is an incredible discovery. The newly-discovered circle and henge should be considered an integral part of Stonehenge rather than a separate monument. Furthermore, it offers tremendous insight into the history of its famous neighbour. Its riverside location demonstrates once again the importance of the River Avon in Neolithic funerary rites and ceremonies.”

The builders of the stone circle used deer antlers as pickaxes. Within the next few months, radiocarbon dating of these antler picks will provide more precise dates and reveal whether the circle was built at the same time as Stonehenge itself (in the decades after 3000 BC) or at some other time.

In the meantime, the discovery of this unknown stone circle may well be exciting confirmation of the Stonehenge Riverside Project’s theory that the River Avon linked a ‘domain of the living’ – marked by timber circles and houses upstream at the Neolithic village of Durrington Walls (discovered by the Project in 2005) – with a ‘domain of the dead’ marked by Stonehenge and this new Bluestonehenge circle.

There is no evidence that the circle had a particular orientation or even an entrance. Soil that fell into the holes when the stones were removed was full of charcoal, showing that plenty of wood was burned here. Yet this was not a place where anyone lived: the pottery, animal bones, food residues and flint tools used in domestic life during the Stone Age were absent.

Professor Mike Parker Pearson, from the University of Sheffield and principal director of the project, said: “It could be that Bluestonehenge was where the dead began their final journey to Stonehenge. Not many people know that Stonehenge was Britain’s largest burial ground at that time. Maybe the bluestone circle is where people were cremated before their ashes were buried at Stonehenge itself.”

Professor Julian Thomas, a co-director from Manchester University, added: “The implications of this discovery are immense. It is compelling evidence that this stretch of the River Avon was central to the religious lives of the people who built Stonehenge. Old theories about Stonehenge that do not explain the evident significance of the river will have to be re-thought.”

(Photo: Peter Dunn)

University of Bristol

LARGEST DINOSAUR FOOTPRINTS EVER FOUND DISCOVERED NEAR LYON, FRANCE

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Footprints from sauropod dinosaurs, giant herbivores with long necks, were found in Plagne, near Lyon, France. Discovered by Marie-Hélène Marcaud and Patrice Landry, two nature enthusiasts, the dinosaur footprints have been authenticated by Jean-Michel Mazin and Pierre Hantzpergue, both of the Paléoenvironnements et Paléobiosphères laboratory (CNRS / Université Claude Bernard Lyon 1). According to the researchers' initial analyses, these dinosaur footprints are the largest found to date.

Furthermore, the tracks spread over dozens and possibly even hundreds of meters. More significant digs will be conducted over the next few years and could result in the Plagne site being one of the largest known dinosaur sites on earth.

Marie-Hélène Marcaud, Patrice Landry and other members of the Société des naturalistes d'Oyonnax (SDNO) have been searching for dinosaur footprints for years. Convinced that the region had a rich paleontological heritage, they focused on potential sites and have been exploring them systematically. The SDNO is thus responsible for a number of discoveries.

It was during one of these outings, on April 5, 2009, that Marie-Hélène Marcaud and Patrice Landry discovered the extraordinary footprints at Plagne. They contacted Jean-Michel Mazin and Pierre Hantzpergue, of the Paléoenvironnements et Paléobiosphères laboratory (CNRS / Université Claude Bernard Lyon 1). The researchers authenticated the footprints based on morphological criteria and the sediment containing them. They believe that the Plagne site was along a route used by sauropod dinosaurs. The dinosaur footprints in Plagne are circular depressions surrounded by a fold of limestone sediment. These depressions are very large, up to 1.50 m in total diameter, suggesting that the animals were larger than 40 tonnes and 25 meters in length. The limestone dates to the Tithonian stage (Upper Jurassic, -150MY), a period during which the area was covered by a warm and shallow sea. The discovery of these footprints shows that sauropods moved around during a phase of emersion of the area, when sea levels were low.

The Plagne site is exceptional, both for the size of the prints and the number of tracks which can be seen and those potentially left to discover. Geological studies and digs of such a large surface area require significant technical and human resources over several years. This work will benefit from the presence of teams from the CNRS/Université Claude Bernard Lyon 1 laboratory, as well as from SDNO.

(Photo: © CNRS Photothèque/Hubert RAGUET)

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