Spider love: Little guys get lots more
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Big males outperform smaller ones in head-to-head mating contests but diminutive males make ten times better lovers because they’re quicker to mature and faster on their feet, a new study of redback spiders reveals.
Published in the current online issue of Journal of Evolutionary Biology, the study shows the importance of maturation in defining mating and paternity success. In field enclosures, researchers simulated two competitive contexts favouring the development of differently sized male redbacks (Latrodectus hasselti). The larger males were more successful at mating with and impregnating females when they competed directly with smaller males. However, when faster maturing smaller males were given a one-day head start, reflecting their earlier maturation in nature, they had a ten-times higher paternity rate than larger males.
Courtship between redbacks lasts an average of 50 minutes when males are competing and 4.5 hours for single, non-competing males. Copulation lasts from 6 to 31 minutes, and males are usually injured or killed during the process.
Men Are Red, Women Are Green, Brown Researcher Finds
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Men are red. Women are green.
Michael J. Tarr, a Brown University scientist, and graduate student Adrian Nestor have discovered this color difference in an analysis of dozens of faces. They determined that men tend to have more reddish skin and greenish skin is more common for women.
The finding has important implications in cognitive science research, such as the study of face perception. But the information also has a number of potential industry or consumer applications in areas such as facial recognition technology, advertising, and studies of how and why women apply makeup.
“Color information is very robust and useful for telling a man from a woman,” said Tarr, the Sidney A. and Dorothea Doctors Fox Professor of Ophthalmology and Visual Sciences and professor of cognitive and linguistic sciences at Brown. “It’s a demonstration that color can be useful in visual object recognition.”
Discovery of new gene associated with diabetes risk suggests link with body clock
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A connection between the body clock and abnormalities in metabolism and diabetes has been suggested in new research by an international team involving the University of Oxford, the Wellcome Trust Sanger Institute and the MRC Epidemiology Unit in Cambridge.
The researchers have identified a gene involved in the way the body responds to the 24 hour day-night cycle that is strongly linked to high blood sugar levels and an increased risk of type 2 diabetes. The results of the genome-wide association scan are published in Nature Genetics.
“We have extremely strong, incontrovertible evidence that the gene encoding melatonin receptor 1B is associated with high fasting glucose levels and increased risk of type 2 diabetes,” says Professor Mark McCarthy of the Oxford Centre for Diabetes, Endocrinology and Metabolism at the University of Oxford.
Many Americans miss exercise goals
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Many Americans are failing to meet the minimum recommendations for exercise, although confusing guidelines are making it difficult to assess, researchers reported on Thursday.
Depending on which federal exercise recommendations are used, either about half or about two-thirds of Americans meet minimum goals, the team at the U.S. Centers for Disease Control and Prevention found.
“Additional efforts are needed to further increase physical activity,” they concluded in the CDC’s weekly report on death and disease.
Cancer patients’ depression tied to family woes
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Treating cancer patients’ depression may help their children stay mentally healthy too, new research in the Journal of Clinical Oncology suggests.
Dr. Florence Schmitt of the University Hospital of Turku in Finland and her colleagues conducted a study of 381 families in which a parent had cancer. They found that, overall, the families of cancer patients were doing well, but that an ill parent’s depression or physical impairment was linked to worse family function.
“Support systems need to be more family-oriented and child-centered in their approach to cancer psychosocial care,” Schmitt and her team write in the Journal of Clinical Oncology.
European origin may up Latinas’ breast cancer risk
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Among United States Latinas, a greater degree of European genetic ancestry is associated with an increased risk of breast cancer, the results of a new study indicate. This could be due to environmental factors, genetic factors, or the interplay of the two, the study team suggests.
Latina women generally have a lower risk of breast cancer compared with European, African-American or non-Latina white women do, according to the report, which published in Cancer Research. This is partially explained by differences in the number of known risk factors; but genetics may also be involved.
Latinas are a group originating from genetically divergent populations, mostly Europeans and Indigenous Americans, note Dr. Laura Fejerman of the University of California, San Francisco, and colleagues. In their study, the researchers evaluated the genetic ancestry of 440 Latinas with breast cancer and 597 Latinas without breast cancer.
Even moderate drinking in pregnancy harmful: study
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Children born to women who have as little as one drink a week during pregnancy are more likely to have symptoms of behavior problems as teens, according to research published this month in the journal Pediatrics.
“If women stop drinking during pregnancy, they can save themselves a lot of heartache later. Being the parent of a child with conduct disorder is really frustrating,” Dr. Elizabeth R. Disney of Chase Braxton Health Services in Baltimore, one of the researchers on the study, told Reuters Health.
The ill effects of heavy drinking during pregnancy, specifically the cluster of social and cognitive problems known as fetal alcohol syndrome, are well known, Disney and her team note in their report. There is also evidence that even a low level of prenatal alcohol exposure is associated with aggressiveness, delinquency and other so-called “externalizing behaviors.” But women who drink during pregnancy are themselves more likely to have these and other problems—and may tend to choose mates that have such problems as well, the researchers point out.
Danish firm to give African children free insulin
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The world’s biggest maker of insulin on Wednesday pledged to provide diabetes care, including free medication, to 10,000 children in African countries to combat a hidden killer.
Danish pharmaceutical firm Novo Nordisk said it had a moral obligation to save lives in places where insulin was too expensive for families and aid efforts have focused on more prominent diseases such as AIDS or malaria.
“Lots of children in the developing world are dying of diabetes when we have had a life-saving drug for 85 years,” said Jean-Claude Mbanya, president-elect of the International Diabetes Federation, at an event in Paris to launch the Novo Nordisk project.
South African dies of suspected deadly virus in Rio
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Brazilian health officials were monitoring people in Rio de Janeiro for possible infections on Wednesday, after a South African man on a business trip died of a suspected hemorrhagic virus.
The body of the 53-year-old man, who arrived in Brazil on Nov. 23 and began showing symptoms two days later, was being repatriated to South Africa in a zinc-sealed coffin, the Ministry of Health said in a statement.
Brazilian media reported officials as saying he may have been infected when he was a patient at a hospital in South Africa where four people died from a new strain of arenavirus, which also includes the germ that causes Lassa fever.
Researchers link C-section babies to asthma risk
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Babies born by Caesarean section are more likely to develop asthma than children delivered naturally, Swiss researchers said on Tuesday.
There has been conflicting evidence on the link between asthma and C-sections but the researchers said the number of children involved in their study and a long monitoring period strengthened their results.
The findings also underscore the potential risks of elective C-sections as more women in Western countries choose to avoid a natural birth, the researchers said in the medical journal, Thorax.
U.S. study weighs lifetime risks from CT scans
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As many as 7 percent of patients from a large U.S. hospital system had enough radiation exposure from CT scans during their lifetime to slightly raise their risk of cancer, U.S. researchers said on Tuesday.
The finding is part of an effort to develop tools that help doctors assess a patient’s overall cancer risk from exposure to computed tomography, or CT scans, researchers from Brigham and Women’s Hospital in Boston told a meeting of the Radiological Society of North America in Chicago.
CT scans—an X-ray machine that rotates around the body taking different images—speed diagnosis of illness and injuries, and are routinely used to track the advance of cancer. But a number of recent studies have raised alarms about the potential cancer risks from the radiation.
Alcohol linked with irregular heartbeat in women
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Consuming two or more alcoholic beverages per day may slightly increase the risk of developing an irregular heartbeat , also referred to as atrial fibrillation, in women, according to a report in the Journal of the American Medical Association.
Prior research established a similar association in men, but the question remained open in women because earlier studies were underpowered to assess the risk, lead author Dr. David Conen, from University Hospital, Basel, Switzerland, and colleagues note.
Atrial fibrillation, the most common arrhythmia, occurs when rapid, disorganized electrical signals in the heart cause very fast and irregular contractions (fibrillations), resulting in inefficient pumping of blood through the heart. Although atrial fibrillation may not cause symptoms, the condition still increases the risk of stroke. Atrial fibrillation may also lead to chest pain, heart attack or heart failure.
Kids take responsibility for asthma meds early
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Many children with asthma start taking their daily medication on their own at an early age, a new study finds.
The findings suggest that even young children should be included when doctors and parents discuss asthma management, researchers report in the journal Pediatrics.
In surveys of 351 parents of asthmatic children and teenagers, the researchers found that by the age of 7, children were giving themselves their daily controller medication nearly 20 percent of the time. By age 11, they were responsible for taking their medication about half of the time.
Daily controller medication refers to the drugs, such as inhaled corticosteroids, that asthma patients take to reduce airway inflammation and prevent attacks of breathlessness and wheezing.
Cancer patients’ race may affect well-being
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Emotional and social quality of life reports from cancer patients may be influenced by race and ethnicity, researchers report the Journal of Pain and Symptom Management.
“Specifically,” Dr. Deepa Rao told Reuters Health, “African-Americans with cancer reported poorer physical and social well-being, but better emotional well-being, than European-Americans.”
Rao, of Feinberg School of Medicine at Northwestern University in Chicago, and colleagues examined how race or ethnicity might influence the social and emotional well-being of cancer patients. Previous studies found poorer physical health among African-Americans compared with European-Americans.
Asthma may boost pneumococcal infection risk
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People with asthma are at increased risk of serious infection with pneumococcal bacteria, according to a new analysis of medical records.
The findings, along with the high fatality rate from such infections, suggest that adults with asthma would benefit from the pneumococcal vaccine, Dr. Young J. Juhn of the Mayo Clinic in Rochester, Minnesota and colleagues say. However, the ability of asthmatics to react normally to the vaccine must be determined before such recommendations can be made, they add.
A previous study found that Medicaid patients with asthma were more than twice as likely to contract invasive pneumococcal disease, in which pneumococcal pneumonia develops and the bacteria invades the bloodstream or the membranes surrounding the brain, Juhn and colleagues note.
