Body

Babies born by caesarean section are more likely to be overweight or obese as adults, according to a new analysis.

The odds of being overweight or obese are 26 per cent higher for adults born by caesarean section than those born by vaginal delivery, the study found (see footnote).

The finding, reported in the journal PLOS ONE, is based on combined data from 15 studies with over 38,000 participants.

Blunt force trauma to the skull of a mummy with signs of Chagas disease may support homicide as cause of death, which is similar to previously described South American mummies, according to a study published February 26, 2014 in PLOS ONE by Stephanie Panzer from Trauma Center Murau, Germany, and colleagues, a study that has been directed by the paleopathologist Andreas Nerlich from Munich University.

The convergent evolution of tail shapes in diving birds may be driven by foraging style, according to a paper published in PLOS ONE on February 26, 2014 by Ryan Felice and Patrick O'Connor from Ohio University.

In the last year or two, you may have had some moments — during elections, sporting events, or weather incidents — when you found yourself sending out a flurry of messages on social media sites such as Twitter.

You are not alone, of course: Such events generate a huge volume of social-media activity. Now a new study published by researchers in MIT's Senseable City Lab shows that social-media messages grow shorter as the volume of activity rises at these particular times.

BOSTON (Feb. 27) – A study in this week's New England Journal of Medicine potentially has significant implications for prenatal testing for major fetal chromosome abnormalities. The study found that in a head-to-head comparison of noninvasive prenatal testing using cell free DNA (cfDNA) to standard screening methods, cfDNA testing (verifi® prenatal test, Illumina, Inc.) significantly reduced the rate of false positive results and had significantly higher positive predictive values for the detection of fetal trisomies 21 and 18.

BLOOMINGTON, Ind. -- An Indiana University study in collaboration with medical researchers from Karolinska Institute in Stockholm has found that advancing paternal age at childbearing can lead to higher rates of psychiatric and academic problems in offspring than previously estimated.

In the cells of humans and other organisms, only a subset of genes are active at any given time, depending largely on the stage of life and the particular duties of the cell. Cells use different molecular mechanisms to orchestrate the activation and deactivation of genes as needed. One central mechanism is an intricate DNA packaging system that either shields genes from activation or exposes them for use.

Helsinki/Jülich/Leipzig. Scientists made an important step in order to better understand the relationships between vegetation and climate. So-called extremely low-volatility organic compounds, which are produced by plants, could be detected for the first time during field and laboratory experiments in Finland and Germany. These organic species contribute to the formation of aerosol that can affect climate and air quality, they report in this week's issue of the journal Nature.

Brown marmorated stink bugs cause millions of dollars in crop losses across the United States because of the damage their saliva does to plant tissues. Researchers at Penn State have developed methods to extract the insect saliva and identify the major protein components, which could lead to new pest control approaches.

The National Heart, Lung, and Blood Institute, part of the National Institutes of Health, released the largest and most comprehensive health and lifestyle analysis of people from a range of Hispanic/Latino origins. The data will enable individuals, communities, and policy makers to tailor better health intervention strategies.

ROCHESTER, Minn. — Feb. 26, 2014 — Somali Americans develop twice the antibody response to rubella from the current vaccine compared to Caucasians in a new Mayo Clinic study on individualized aspects of immune response. A non-Somali, African-American cohort ranked next in immune response, still significantly higher than Caucasians, and Hispanic Americans in the study were least responsive to the vaccine. The findings appear in the journal Vaccine.

Activation of beta-catenin, the primary mediator of the ubiquitous Wnt signaling pathway, alters the immune system in lasting and harmful ways, a team of Chicago-based researchers demonstrate in the February 26, 2014, issue of Science Translational Medicine.

Melanoma is particularly dangerous because it can form metastases in vital organs such as the lungs, liver or brain. UV radiation is considered to be the most significant triggering factor. An interdisciplinary team of researchers from the University Hospital and the LIMES Institute of the University of Bonn has now discovered that sunburns contribute to the development of this malignant disease not only through direct alteration of pigment cell genomes but also indirectly through inflammatory processes in the surrounding tissue.

According to their results, these extremely low-volatile organic compounds consist of relatively large molecules which contain an almost equal number of carbon, oxygen, and hydrogen atoms. The scientists present a plausible explanation supported by numerous experimental findings of how these vapours are formed almost immediately when plant emissions (e.g. monoterpenes) are released into the air.

A genus of cockroach in the poorly studied family Corydiidae has been revised for the first time since 1920. The revision has resulted in the discovery and description of 39 new species of Arenivaga, a genus which previously held nine species. The Corydiidae family of roaches is found worldwide and its constituents are frequently found in harsh, dry habitats not usually associated with cockroaches. They are also often subterranean in their habits making their presence easily overlooked.