Mortality risks of being overweight or obese are underestimated

New research by Andrew Stokes, a doctoral student in demography and sociology in the School of Arts and Sciences at the University of Pennsylvania, suggests that many obesity studies substantially underestimate the mortality risks associated with excess weight in the United States. His study, “Using Maximum Weight to Redefine Body Mass Index Categories in Studies of The Mortality Risks of Obesity,” was published in the March issue of the open-access journal Population Health Metrics.”The scholarly community is divided over a large meta-analysis that found that overweight is the optimal BMI category and that there are no increased risks associated with obese class 1,” Stokes said.Normal weight is indicated by a BMI of 18.5-24.9 kg/m2, overweight is indicated by a BMI of 25.0-29.9 kg/m2, obese class 1 is a BMI of 30.0-34.9 kg/m2 and obese class 2 is a BMI of 35.0 kg/m2 and above.Skeptics of the meta-analysis argue that the findings are likely driven by biases, especially by illness-induced weight loss.”Using BMI at the time of the survey to assess the mortality risks of overweight and obesity is problematic, especially in older populations, because slimness can be a marker of illness,” Stokes said.Researchers have attempted to address this bias by eliminating ill people from their samples; however, according to Stokes, such measures are inadequate because information on illness is ascertained by self-reporting and not everyone with an illness has been diagnosed.Stokes used individuals’ highest BMI in life to predict mortality rates. He said that in the previous literature, the normal weight category combines data from low-risk, stable-weight individuals with high-risk individuals who have experienced weight loss. Use of weight histories makes it possible to separate the two groups and redefine the reference category as people who were a consistently normal weight throughout their lives.Stokes conducted the analyses using data from the National Health and Nutrition Examination Surveys of 1988-1994 and 1999-2004 linked to the National Death Index through 2006 on U.S. adults ages 50-84 who never smoked.He found that the percentage of mortality attributable to overweight and obesity in this group was 33 percent when assessed using maximum BMI. The comparable figure obtained using BMI at the time of survey was substantially smaller at 5 percent.”The source of the discrepancy became clear when I started looking more closely at peoples’ weight histories,” Stokes said.Stokes said that a considerable fraction of individuals classified as normal weight using BMI at time of survey were formerly overweight or obese. This group had substantially elevated mortality rates compared to individuals that were consistently normal weight throughout their lives, suggesting that for many of them the weight loss was related to an illness.He concluded that the findings provide simple and compelling evidence that the prior literature underestimates the impact of obesity on levels of mortality in the U.S. But Stokes said that his results need corroboration in future studies because maximum BMI was calculated from peoples’ recollection of their maximum weight, which may be subject to recall error. He said that his analysis should be replicated using longitudinal data with contemporaneous measures of height and weight across the lifecycle.Story Source:The above story is based on materials provided by University of Pennsylvania. Note: Materials may be edited for content and length.

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Poor rural youth in Haiti are rich in family ties, rooted in their own culture

Oct. 16, 2013 — Haitian teens, especially those who live in the country’s rural areas, are among the poorest persons in the Western Hemisphere, but they are rich in their family relationships and strongly rooted in their own culture, a University of Illinois study finds.”It’s true that rural Haitian teens didn’t directly suffer the major trauma of the 2012 earthquake, but they deal daily with the effects of poverty — not enough food, no money to go to school, a lack of electricity much of the time, little access to clinics or hospitals,” said Gail M. Ferguson, a U of I professor of human development and family studies who studies the cultural identity and well-being of adolescents in the Caribbean, including the effects of exposure to U.S. culture.In the course of a lifetime, chronic exposure to poverty can have the same impact as an earthquake-sized trauma, she said.”However, these teens report having a strong sense of family obligation and an attachment to Haitian culture, which probably protects them and contributes to their resilience,” she said.In the study, the researchers used a survey to measure strength of family obligations and cultural orientation among 105 early adolescents (10 to 14 years) in rural Haiti. Among other findings, she learned that teens, especially boys, believe very strongly that they should respect and obey their parents and assist them when they need help without being paid for it.”Can you imagine how helpful that would be for a family with few resources? That attitude in itself contributes to a close parent-child relationship, which is a positive factor in adolescent development,” she said.Affinity for the teens’ own culture, which has been found to be a protective factor in other populations, was nearly three times as high as American orientation among survey participants.”Haitian culture is known for its creativity and its close community bonds. The arts, particularly visual arts and a love of story, provide an emotional outlet for Haitian youth, helping to channel their emotions, desires, and needs,” she said.This connection to Haitian culture is strong despite the influence of U.S. culture through migration, trade, and technology. The U.S. is the primary destination for Haitian emigrants who continue to communicate with relatives and friends back on the island. …

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Robots take over economy: Sudden rise of global ecology of interacting robots trade at speeds too fast for humans

Sep. 11, 2013 — Recently, the global financial market experienced a series of computer glitches that abruptly brought operations to a halt. One reason for these “flash freezes” may be the sudden emergence of mobs of ultrafast robots, which trade on the global markets and operate at speeds beyond human capability, thus overwhelming the system. The appearance of this “ultrafast machine ecology” is documented in a new study published on September 11 in Nature Scientific Reports.The findings suggest that for time scales less than one second, the financial world makes a sudden transition into a cyber jungle inhabited by packs of aggressive trading algorithms. “These algorithms can operate so fast that humans are unable to participate in real time, and instead, an ultrafast ecology of robots rises up to take control,” explains Neil Johnson, professor of physics in the College of Arts and Sciences at the University of Miami (UM), and corresponding author of the study.”Our findings show that, in this new world of ultrafast robot algorithms, the behavior of the market undergoes a fundamental and abrupt transition to another world where conventional market theories no longer apply,” Johnson says.Society’s push for faster systems that outpace competitors has led to the development of algorithms capable of operating faster than the response time for humans. For instance, the quickest a person can react to potential danger is approximately one second. Even a chess grandmaster takes around 650 milliseconds to realize that he is in trouble — yet microchips for trading can operate in a fraction of a millisecond (1 millisecond is 0.001 second).In the study, the researchers assembled and analyzed a high-throughput millisecond-resolution price stream of multiple stocks and exchanges. From January, 2006, through February, 2011, they found 18,520 extreme events lasting less than 1.5 seconds, including both crashes and spikes.The team realized that as the duration of these ultrafast extreme events fell below human response times, the number of crashes and spikes increased dramatically. They created a model to understand the behavior and concluded that the events were the product of ultrafast computer trading and not attributable to other factors, such as regulations or mistaken trades. Johnson, who is head of the inter-disciplinary research group on complexity at UM, compares the situation to an ecological environment.”As long as you have the normal combination of prey and predators, everything is in balance, but if you introduce predators that are too fast, they create extreme events,” Johnson says. …

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Biologists show that generosity leads to evolutionary success

Sep. 2, 2013 — With new insights into the classical game theory match-up known as the “Prisoner’s Dilemma,” University of Pennsylvania biologists offer a mathematically based explanation for why cooperation and generosity have evolved in nature.Their work builds upon the seminal findings of economist John Nash, who advanced the field of game theory in the 1950s, as well as those of computational biologist William Press and physicist-mathematician Freeman Dyson, who last year identified a new class of strategies for succeeding in the Prisoner’s Dilemma.Postdoctoral researcher Alexander J. Stewart and associate professor Joshua B. Plotkin, both of Penn’s Department of Biology in the School of Arts and Sciences, examined the outcome of the Prisoner’s Dilemma as played repeatedly by a large, evolving population of players. While other researchers have previously suggested that cooperative strategies can be successful in such a scenario, Stewart and Plotkin offer mathematical proof that the only strategies that succeed in the long term are generous ones. They report their findings in PNAS the week of Sept. 2.”Ever since Darwin,” Plotkin said, “biologists have been puzzled about why there is so much apparent cooperation, and even flat-out generosity and altruism, in nature. The literature on game theory has worked to explain why generosity arises. Our paper provides such an explanation for why we see so much generosity in front of us.”The Prisoner’s Dilemma is a way of studying how individuals choose whether or not to cooperate. In the game, if both players cooperate, they both receive a payoff. …

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Art preserves skills despite onset of vascular dementia in ‘remarkable’ case of a Canadian sculptor

Aug. 22, 2013 — The ability to draw spontaneously as well as from memory may be preserved in the brains of artists long after the deleterious effects of vascular dementia have diminished their capacity to complete simple, everyday tasks, according to a new study by physicians at St. Michael’s Hospital.The finding, scheduled to be released today in the Canadian Journal of Neurological Sciences, looked at the last few years of the late Mary Hecht, an internationally renowned sculptor, who was able to draw spur-of-the moment and detailed sketches of faces and figures, including from memory, despite an advanced case of vascular dementia.”Art opens the mind,” said Dr. Luis Fornazzari, neurological consultant at St. Michael’s Hospital’s Memory Clinic and lead author of the paper. “Mary Hecht was a remarkable example of how artistic abilities are preserved in spite of the degeneration of the brain and a loss in the more mundane, day-to-day memory functions.”Hecht, who died in April 2013 at 81, had been diagnosed with vascular dementia and was wheelchair-bound due to previous strokes. Despite her vast knowledge of art and personal talent, she was unable to draw the correct time on a clock, name certain animals or remember any of the words she was asked to recall.But she quickly sketched an accurate portrait of a research student from the Memory Clinic. And she was able to draw a free-hand sketch of a lying Buddha figurine and reproduce it from memory a few minutes later. To the great delight of St. Michael’s doctors, Hecht also drew an accurate sketch of famed cellist Mstislav Rostropovich after she learned of his death earlier that day on the radio.While she was drawing and showing medical staff her own creations, Hecht spoke eloquently and without hesitation about art.”This is the most exceptional example of the degree of preservation of artistic skills we’ve seen in our clinic,” said Dr. …

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Caribbean’s native predators unable to stop aggressive lionfish population growth

July 11, 2013 — “Ocean predator” conjures up images of sharks and barracudas, but the voracious red lionfish is out-eating them all in the Caribbean — and Mother Nature appears unable to control its impact on local reef fish. That leaves human intervention as the most promising solution to the problem of this highly invasive species, said researchers at the University of North Carolina at Chapel Hill.”Lionfish are here to stay, and it appears that the only way to control them is by fishing them,” said John Bruno, professor of biology in UNC’s College of Arts and Sciences and lead investigator of the study. The research has important implications not just for Caribbean reefs, but for the North Carolina coast, where growing numbers of lionfish now threaten local fish populations.Lionfish, native to the Indo-Pacific region, have long been popular aquarium occupants, with their striking stripes and soft, waving fins. They also have venomous spines, making them unpleasant fare for predators, including humans — though once the spines are carefully removed, lionfish are generally considered safe to eat, Bruno said.They have become big marine news as the latest invasive species to threaten existing wildlife populations. Bruno likened their extraordinary success to that of ball pythons, now eating their way through Florida Everglades fauna, with few predators other than alligators and humans.”When I began diving 10 years ago, lionfish were a rare and mysterious species seen deep within coral crevices in the Pacific Ocean,” said Serena Hackerott, lead author and master’s student in marine sciences, also in UNC’s College of Arts and Sciences. “They can now been seen across the Caribbean, hovering above the reefs throughout the day and gathering in groups of up to ten or more on a single coral head.”The international research team looked at whether native reef predators such as sharks and groupers could help control the population growth of red lionfish in the Caribbean, either by eating them or out-competing them for prey. They also wanted to evaluate scientifically whether, as some speculate, that overfishing of reef predators had allowed the lionfish population to grow unchecked.The team surveyed 71 reefs, in three different regions of the Caribbean, over three years. Their results indicate there is no relationship between the density of lionfish and that of native predators, suggesting that, “interactions with native predators do not influence” the number of lionfish in those areas, the study said.The researchers did find that lionfish populations were lower in protected reefs, attributing that to targeted removal by reef managers, rather than consumption by large fishes in the protected areas. Hackerott noted that during 2013 reef surveys, there appeared to be fewer lionfish on popular dive sites in Belize, where divers and reef managers remove lionfish daily.The researchers support restoration of large-reef predators as a way to achieve better balance and biodiversity, but they are not optimistic that this would affect the burgeoning lionfish population.”Active and direct management, perhaps in the form of sustained culling, appears to be essential to curbing local lionfish abundance and efforts to promote such activities should be encouraged,” the study concluded.

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Why do we enjoy listening to sad music?

July 11, 2013 — Sad music might actually evoke positive emotions reveals a new study by Japanese researchers published in the open-access journal Frontiers in Psychology. The findings help to explain why people enjoy listening to sad music, say Ai Kawakami and colleagues from Tokyo University of the Arts and the RIKEN Brain Science Institute, Japan.Kawakami and colleagues asked 44 volunteers, including both musicians and non-specialists, to listen to two pieces of sad music and one piece of happy music. Each participant was required to use a set of keywords to rate both their perception of the music and their own emotional state.The sad pieces of music included Glinka’s “La Séparation” in F minor and Blumenfeld’s Etude “Sur Mer” in G minor. The happy music piece was Granados’s Allegro de Concierto in G major. To control for the “happy” effect of major key, they also played the minor-key pieces in major key, and vice versa.The researchers explained that sad music evoked contradictory emotions because the participants of the study tended to feel sad music to be more tragic, less romantic, and less blithe than they felt themselves while listening to it.”In general, sad music induces sadness in listeners, and sadness is regarded as an unpleasant emotion. If sad music actually evokes only unpleasant emotion, we would not listen to it,” the researchers wrote in the study.”Music that is perceived as sad actually induces romantic emotion as well as sad emotion. And people, regardless of their musical training, experience this ambivalent emotion to listen to the sad music,” added the researchers.Also, unlike sadness in daily life, sadness experienced through art actually feels pleasant, possibly because the latter does not pose an actual threat to our safety. This could help people to deal with their negative emotions in daily life, concluded the authors.”Emotion experienced by music has no direct danger or harm unlike the emotion experienced in everyday life. Therefore, we can even enjoy unpleasant emotion such as sadness. If we suffer from unpleasant emotion evoked through daily life, sad music might be helpful to alleviate negative emotion,” they added.

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What warring couples want: Power, not apologies, study shows

July 9, 2013 — The most common thing that couples want from each other during a conflict is not an apology, but a willingness to relinquish power, according to a new Baylor University study.Giving up power comes in many forms, among them giving a partner more independence, admitting faults, showing respect and being willing to compromise. The study is published in the Journal of Social and Clinical Psychology.”It’s common for partners to be sensitive to how to share power and control when making decisions in their relationship,” said researcher Keith Sanford, Ph.D., an associate professor of psychology and neuroscience in Baylor University’s College of Arts & Sciences.Following closely behind the desire for shared control was the wish for the partner to show more of an investment in the relationship through such ways as sharing intimate thoughts or feelings, listening, and sharing chores and activities, Sanford said.The research results are based on two studies of married or cohabitating people and build upon previous research by Sanford. Earlier studies of more than 3,500 married people found that there are just two basic types of underlying concerns that couples experience during conflicts: “perceived threat,” in which a person thinks that his or her status is threatened by a critical or demanding partner; and “perceived neglect,” in which an individual sees a partner as being disloyal or inattentive and showing a lack of investment in the relationship.In the first of the new studies, 455 married participants (ages 18 to 77, with marriages ranging from less than one year to 55 years) were asked to independently list desired resolutions to a single current or ongoing conflict — anything from a minor disagreement or misunderstanding to a big argument. From those answers, 28 individual categories were identified, which researchers organized into six all-encompassing types of desired resolution.After relinquished power, the desired behaviors from one’s partner — from most to least common — were:• To show investment• To stop adversarial behavior• To communicate more• To give affection• To make an apology”We definitely respond to whether we gain or lose status,” Sanford said. “When we feel criticized, we are likely to have underlying concerns about a perceived threat to status, and when that happens, we usually want a partner simply to disengage and back off.”In a second study, participants completed a 28-item questionnaire measuring how much people wanted each of the categories of desired resolution that were identified in the first study. This study included 498 participants (ages ranging from 19 to 81, with length of marriage ranging from less than one year to 51 years). They did not take part in the first study but were in committed relationships. The findings were consistent with the first study results, Sanford said.”The things couples want from each other during conflicts will depend on their underlying concerns, and to resolve conflicts, they may need to use different tactics to address different underlying concerns,” he said. “The husband might buy flowers, and that might be helpful if his partner has a concern involving perceived neglect. But if the partner has a concern involving perceived threat, then the flowers won’t do much to address the issue.”*Sanford has developed a free interactive internet program for couples titled the “Couple Conflict Consultant” at www.pairbuilder.com The program provides a personalized assessment of 14 areas of conflict resolution and a large resource bank of information and recommendations for couples.

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‘Spiritual’ young people more likely to commit crimes than ‘religious’ ones

June 12, 2013 — Young adults who deem themselves “spiritual but not religious” are more likely to commit property crimes — and to a lesser extent, violent ones — than those who identify themselves as either “religious and spiritual” or “religious but not spiritual,” according to Baylor University researchers.The sociologists’ study, published in the journal Criminology, also showed that those in a fourth category — who say they are neither spiritual nor religious — are less likely to commit property crimes than the “spiritual but not religious” individuals. But no difference was found between the two groups when it came to violent crimes.”The notion of being spiritual but not associated with any organized religion has become increasingly popular, and our question is how that is different from being religious, whether you call yourself ‘spiritual’ or not,” said Sung Joon Jang, Ph.D., an associate professor of sociology in Baylor’s College of Arts & Sciences. He is lead author of the study, “Is Being ‘Spiritual’ Enough Without Being Religious? A Study of Violent and Property Crimes Among Emerging Adults.”He noted that until the 20th century, the terms “religious” and “spiritual” were treated as interchangeable.Previous research indicated that people who say they are religious show lower levels of crime and deviance, which refers to norm-violating behavior.The researchers analyzed data from a sample of 14,322 individuals from the National Longitudinal Study of Adolescent Health. They ranged in age from 18 to 28, with an average age of 21.8.In the confidential survey, participants were asked how often they had committed crimes in the previous 12 months — including violent crimes such as physical fights or armed robbery — while property crimes included vandalism, theft and burglary.Past research shows that people who report themselves as spiritual make up about 10 percent of the general population, Jang said.”Calling oneself ‘spiritual but not religious’ turned out to more of an antisocial characteristic, unlike identifying oneself as religious,” said Baylor researcher Aaron Franzen, a doctoral candidate and study co-author.In their study, the Baylor researchers hypothesized that those who are spiritual but not religious would be less conventional than the religious group — but could be either more or less conventional than the “neither” group.”We were thinking that religious people would have an institutional and communal attachment and investment, while the spiritual people would have more of an independent identity,” Franzen said.Theories for why religious people are less likely to commit crime are that they fear “supernatural sanctions” as well as criminal punishment and feel shame about deviance; are bonded to conventional society; exercise high self-control in part because of parents who also are likely to be religious; and associate with peers who reinforce their behavior and beliefs.Significantly, people who are spiritual but not religious tend to have lower self-control than those who are religious. They also are more likely to experience such strains as criminal victimization and such negative emotions as depression and anxiety. They also are more likely to have peers who use and abuse alcohol, Franzen said. Those factors are predictors of criminal behavior.”It’s a challenge in terms of research to know what that actually means to be spiritual, because they self-identify,” he said. “But they are different in some way, as our study shows.”In their research, sociologists included four categories based on how the young adults reported themselves. Those categories and percentages were:• Spiritual but not religious, 11.5 percent• Religious but not spiritual, 6.8 percent• Both spiritual and religious, 37.9 percent• Neither spiritual nor religious, 43.8 percent

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