Medical Health Center

Assortative Mating And The Role Of Phenotypic Plasticity In Male Competition: Implications For Gene Flow Among Host-associated Parasitoid Populations

This manuscript investigates mating preference in conjunction with phenotypic plasticity using Aphidius parasitoids adapted to different host species.

Males actively attempted to assortatively mate, but actual mating outcomes were strongly influenced by the relative size of the adult males.

Results are discussed in the context of assortative mating in combination with the success of migrant males in mitigating gene flow between host-associated parasitoid populations.

Royal Society journal Biology Letters

Biology Letters publishes short, innovative and cutting-edge research articles and opinion pieces accessible to scientists from across the biological sciences. The journal is characterised by stringent peer-review, rapid publication and broad dissemination of succinct high-quality research communications.

Biology Letters

Avian Migrants Adjust Migration In Response To Environmental Conditions En Route

Climate change is driving a rapid change in breeding area arrival for long-distance migrants. However, little is known about the climatic factors affecting migratory birds during the migration cycle.

We show that passage of the Sahara Desert is delayed and correlated with improved conditions in the wintering areas, while birds travel more rapidly through Europe, and adjust their breeding area arrival time in response to improved environmental conditions en route.

Hence, different phenological patterns at different latitudes and between migratory routes seem to be caused by phenotypic responses to spatial variability in the environmental conditions en route.

Royal Society journal Biology Letters

Biology Letters publishes short, innovative and cutting-edge research articles and opinion pieces accessible to scientists from across the biological sciences. The journal is characterised by stringent peer-review, rapid publication and broad dissemination of succinct high-quality research communications.

Biology Letters

Differential Selection According To The Degree Of Cheating In A Status Signal

A badge of status is arbitrary morphological markings of animals, which evolved to avoid unnecessary fights.

The maintenance of honesty in a badge-of-status system is not fully understood, despite many studies. Our experiment examined the relationship between badge size and winter survival, and the long-term costs of cheating, by manipulating badge size in male house sparrows.

Interestingly, in the experimental (badge-enlargement) group, males with originally large badges had increased winter survival, whereas males with originally small badges had decreased survival. Therefore, the degree of cheating affected their rates of survival (i.e. the more cheating, the more likely to die).

Royal Society journal Biology Letters

Biology Letters publishes short, innovative and cutting-edge research articles and opinion pieces accessible to scientists from across the biological sciences. The journal is characterised by stringent peer-review, rapid publication and broad dissemination of succinct high-quality research communications.

Biology Letters

Diversity Increases Biomass Production For Trematode Parasites In Snails

At first glance, 1A + 1B > 1A, might appear to be self-evident. But this is a contested premise behind a potential value of biodiversity -e.g., whether multi-species assemblages produce more biomass than do single-species assemblages.

We extend diversity versus production research by examining assemblages of parasitic castrator worms. We found that diverse castrator assemblages produced more biomass than single-species assemblages. Also, assemblages where species partitioned space had the greatest diversity effects.

Study of these simple assemblages enabled a test of the universality of diversity effects, and also a clarification of the mechanisms by which species diversity influences ecological process.

Proceedings of the Royal Society B: Biological Sciences

Proceedings B is the Royal Society’s flagship biological research journal, dedicated to the rapid publication and broad dissemination of high-quality research papers, reviews and comment and reply papers. The scope of journal is diverse and is especially strong in organismal biology.

Proceedings of the Royal Society B: Biological Sciences

Optimism software helps you fight depression

Depression is no joke. It’s the best that you can identify it and tackle it at the earliest stage. Or else it’ll most probably develop into more serious illness.

The depression software is called Optimism Mac OS X.

If you have a geeky title=”Depression Optimism Software” alt=”Depression Treatment Software With Optimism”>

Increased Coordination Between CMS, IHS Could Improve Quality Of Care For American Indians, GAO Report Finds

Increased coordination between CMS and the Indian Health Service could improve the quality of health care provided to American Indians and Alaska Natives, according to a Government Accountability Office report released on Monday, CQ HealthBeat reports. For the report, GAO examined documents, interviewed government officials and visited some American Indian tribes and facilities funded by IHS to determine the level of coordination between CMS and IHS. The report also examined problems with Medicare and Medicaid enrollment for American Indians and Alaska Natives.

According to the report, CMS could improve communication of policy changes that would affect facilities funded by IHS. The report recommended that CMS inform IHS about policy changes early in the development process to allow time for review of proposed rules before public comment periods end. CMS has begun to improve efforts to identify policy changes that would affect facilities funded by IHS, the report found. In addition, the report found that some coordination occurs between CMS and IHS, such as an effort by the agency to train staff at facilities funded by IHS on Medicare and Medicaid issues.

In a statement, Senate Finance Committee Chair Max Baucus (D-Mont.) said, “This report shows us that there are still hurdles that keep all Americans from getting the best health care available, regardless of which agencies help them get it,” adding, “We shouldn’t let the distance between IHS and CMS get in the way of quality, affordable health care for American Indians and Alaska Natives” (Blair Wyckoff, CQ HealthBeat, 8/11).

The report is available online (.pdf).

Reprinted with kind permission from http://www.kaisernetwork.org. You can view the entire Kaiser Daily Health Policy Report, search the archives, or sign up for email delivery at http://www.kaisernetwork.org/dailyreports/healthpolicy. The Kaiser Daily Health Policy Report is published for kaisernetwork.org, a free service of The Henry J. Kaiser Family Foundation.

© 2008 Advisory Board Company and Kaiser Family Foundation. All rights reserved.

UBC Study Of Olympic Athletes Shows That Pride And Shame Are Universal And Innate Expressions

The victory stance of a gold medalist and the slumped shoulders of a non-finalist are innate and biological rather than learned responses to success and failure, according to a University of British Columbia study using cross-cultural data gathered at the 2004 Olympic and Paralympic Games.

In the first study of its kind, UBC psychology researcher Jessica Tracy investigated how pride and shame are expressed across cultures, and among the congenitally blind. She compared the non-verbal expressions and body language of sighted, blind, and congenitally blind judo competitors representing more than 30 countries, among them Algeria, Taiwan, North Korea, the Ukraine and the United States.

Asst. Prof. Tracy’s findings - published in this week’s online Early Edition of the journal Proceedings of the National Academy of Sciences - show that the individuals displayed pride and shame behaviours in response to the same success and failure situations.

Pride, unlike fear, anger or joy - which are categorized as primary emotions - has received little research attention in the past, explains Tracy. Her work explores how pride as an innate human biological response has evolved through time and shapes human social dynamics.

“Since congenitally blind individuals could not have learned pride and shame behaviors from watching others, these displays of victory or defeat are likely to be an innate biological propensity in humans, rather than learned behaviour,” says Tracy.

Tracy and co-author Psychology Prof. David Matsumoto of San Francisco State University analyzed photos taken by an official International Judo Federation photographer who was not told about the specific research goals. The photographer shot the athletes during and immediately after each match, repeatedly for approximately 15 seconds, allowing for a series of moment-by moment images of each behavioural response.

The researchers coded the athletes’ head, arms and body positions. They found that winning athletes, both sighted and blind and across all cultures, tended to raise their arms, tilt their head up and puff out their chest. Also largely universal were the expressions of defeat, which include slumped shoulders and a narrowed chest.

The researchers found that, to some extent, culture moderated the shame response among sighted athletes. It was less pronounced among individuals from highly individualistic, self-expression-valuing cultures, primarily in North America and West Eurasian countries. However, congenitally blind athletes across cultures showed the shame response, suggesting that the cultural difference found among sighted athletes was due to the Western cultural norm of hiding one’s shame.

“These findings support evolutionary accounts that pride and shame would have been powerful mechanisms in enhancing or inhibiting an individual’s social status,” says Tracy.

Source:
Jessica Tracy
University of British Columbia

Overweight Hispanic Children At Significant Risk For Pre-Diabetes

A study by researchers at the University of Southern California (USC) found that overweight Hispanic children are at significant risk for pre-diabetes, a condition marked by higher than normal blood glucose levels that are not yet high enough for a diagnosis of diabetes. The persistence of pre-diabetes during growth is associated with progression in risk towards future diabetes, according to the study, which will be published in an upcoming issue of the journal Diabetes, and is now available online.

With a population of more than 35 million, Hispanics are the largest and fastest growing minority group in the United States. Despite the fact that Hispanics are at high risk for developing type 2 diabetes, few previous studies have looked at physiological causes of the disease within this population.

Researchers led by Michael I. Goran, Ph.D., professor of preventive medicine, physiology and biophysics and pediatrics, and director of the USC Childhood Obesity Research Center at the Keck School of Medicine of USC, followed a cohort of 128 overweight Hispanic children in East Los Angeles. The children were tested over four consecutive years for glucose tolerance, body mass index, total body fat and lean mass and other risk factors for type 2 diabetes. The study found that an alarming 13% of the children had what the investigators termed “persistent pre-diabetes.”

Most prior studies examining pre-diabetes in overweight and obese children looked at a one-time assessment of metabolic risk factors for type 2 diabetes, but fluctuations over time led to poor reliability for these tests. In the new study, Goran and colleagues examined longitudinal data to look at a progression of risk factors over four years. Children were identified as having persistent pre-diabetes if they had three to four positive tests over four annual visits. The children who had persistent pre-diabetes had signs of compromised beta-cell function, meaning that their bodies were unable to fully compensate to maintain blood glucose at an appropriate level, and they had increasing accumulation of visceral fat or deposition of fat around the organs. Both of these outcomes point towards progression in risk towards type 2 diabetes.

“What this study shows is that doctors should be doing regular monitoring of these children over time, because a one-time checkup might not be enough to tell if they are at risk for developing diabetes,” Goran says.

Visceral fat, which pads the spaces between abdominal organs, has been linked to metabolic disturbances and increased risk for cardiovascular disease and type 2 diabetes.

Increased obesity has been identified as a major determinant of insulin resistance. Lower beta-cell function is a key component in the development of type 2 diabetes, as the cells are unable to produce enough insulin to adequately compensate for the insulin resistance.

“To better treat at-risk children we need better ways to monitor beta-cell function and visceral fat buildup,” Goran says. “Those are tough to measure but are probably the main factors determining who will get type 2 diabetes.”

Future studies will examine different interventions, including improving beta-cell function and reducing visceral fat.

“The study provides great insight into the risk factors that lead to the progression towards type 2 diabetes in this population,” says Francine Kaufman, professor of pediatrics at the Keck School of Medicine at USC and head of the division of endocrinology and metabolism at Childrens Hospital Los Angeles, who was not directly involved in the study. “Only by understanding how this devastating disease develops will be able to begin taking steps to prevent it.”

The study was supported by the National Institutes of Health and the General Clinical Research Center, National Center for Research Resources.

Michael I. Goran, Christianne Lane, Claudia Toledo-Corral and Marc J. Weigensberg. “Persistence of Pre-Diabetes in Overweight and Obese Hispanic Children: Association With Progressive Insulin Resistance, Poor Beta-cell Function and Increasing Visceral Fat.”Diabetes. DB-08-0445

University of Southern California Health Sciences
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Measure Would Remove Beneficiaries’ Social Security Numbers From Medicare Cards

Legislation (HR 6600) recently introduced in the House would remove beneficiaries’ Social Security numbers from Medicare cards to help prevent identity theft, CQ HealthBeat reports. The measure, introduced by Rep. Lloyd Doggett (D-Texas), would require that Medicare remove, code or embed beneficiaries’ Social Security numbers in their cards.

According to a release from Doggett, other than Social Security cards, the Medicare card is the most commonly issued government document displaying a person’s Social Security number. The measure is in response to a May report from the Social Security Administration Office of Inspector General that recommended Social Security numbers be removed from Medicare cards, according to the release. Doggett in the release said, “Forty-four million Americans carry in their wallet or purse something that makes them needlessly more vulnerable to identify theft — it’s their Medicare card,” adding, “Their savings and credit should not be put at risk if someone steals their Medicare card” (Naresh, CQ HealthBeat, 8/8).

Reprinted with kind permission from http://www.kaisernetwork.org. You can view the entire Kaiser Daily Health Policy Report, search the archives, or sign up for email delivery at http://www.kaisernetwork.org/dailyreports/healthpolicy. The Kaiser Daily Health Policy Report is published for kaisernetwork.org, a free service of The Henry J. Kaiser Family Foundation.

© 2008 Advisory Board Company and Kaiser Family Foundation. All rights reserved.

Immune Activation Suppresses Plasma Testosterone Level; A Meta-Analysis

Males of many species attract females with sexual displays and ornaments. What causes some males to signal at lower rates than others?

Signaling intensity is under the influence of testosterone, and we show that activation of the immune system result in lower testosterone levels.

Thus males that have more infections have lower testosterone, and hence signal at a lower rate.

Thus females can select healthy fathers on the basis of sexual displays, explaining also why they pay attention to these displays.

Royal Society journal Biology Letters

Biology Letters publishes short, innovative and cutting-edge research articles and opinion pieces accessible to scientists from across the biological sciences. The journal is characterised by stringent peer-review, rapid publication and broad dissemination of succinct high-quality research communications.

Biology Letters