Scientific American Online

The Oxford University Press has launched an online version of the Oxford Textbook of Medicine, complete with all the text, figures and illustrations that make up the three-volume, 6,000-page, 25-pound print behemoth. The book is a classic among generations of doctors and medical students, and it is considered the ultimate medical reference book by other professionals including lawyers and journalists. [More]

When surveyed, most people say they get tattoos or unconventional piercings to express individuality. But could something more psychologically primal be afoot? Researchers at the University of Wroclaw in Poland measured about 200 men and women--half of them inked or pierced in places other than their earlobes--for body symmetry, or how similar their right and left sides are. (More similarity indicates genetic health and is associated with sexual attractiveness.)

Among the research subjects, men with bodily decorations exhibited greater symmetry than those without, whereas no differences emerged in women. Because people who are less symmetric did not opt more often for tattoos and piercings, researchers rejected one widely held hypothesis that suggested people use physical graffiti to hide or distract from imperfections in their appearance.

Drive: The Surprising Truth about What Motivates Us by Daniel H. Pink. Riverhead Books, 2009

Life, the Multiverse and Everything In “ Looking for Life in the Multiverse ,” Alejandro Jenkins and Gilad Perez say that life would be possible in a universe without the weak nuclear force. But they fail to note that the weak force is unique in treating matter and antimatter asymmetrically. Only because of this asymmetry did matter slightly outweigh antimatter before nearly all antimatter annihilated with an equal amount of matter, within the first seconds after the big bang. Everything we see--including stars, which are essential to life--is composed of that slight excess of matter. A universe without the asymmetric weak force would have virtually no normal matter and hence no life in any form we might recognize. [More]

Researchers sequencing Neandertal DNA have concluded that between 1 and 4 percent of the DNA of people today who live outside Africa came from Neandertals, the result of interbreeding between Neandertals and early modern humans.

A team of scientists led by Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig pieced together the first draft of the sequence--which represents about 60 percent of the entire genome--using DNA obtained from three Neandertal bones that come from Vindija cave in Croatia and are more than 38,000 years old. The researchers detail their analysis of the sequence in the May 7 Science.

At a test in the New Mexico desert this morning, NASA carried off what it called a successful test of a launch abort system for Orion, the crew capsule designed to return astronauts to orbit and beyond after the space shuttle retires this year or next. The system, which would rocket the crew to safety in the event of an emergency on the launch pad or during ascent, roared into the sky at 9:00 A.M. Eastern Daylight Time from White Sands Missile Range. A dummy crew capsule then detached and parachuted back to Earth about two minutes later. [More]

Shakespeare's Lady Macbeth could never wash away the guilt of murder from her hands, but research has shown that the simple act of hand washing--or even using a wipe--can in fact help people clean their conscience of dirty deeds . A new study, published online May 6 in Science , reveals the power of hand washing to ease people's minds about even mundane decisions . [More]

Antarctica is nature's forensic freezer, preserving records of the past in layers of largely unsullied ice and snow that scientists have dug up to explore past geologic and atmospheric conditions. The southernmost continent has also proved an ideal hunting ground for meteorites, which stand out atop ice sheets and snowfields and tend to undergo little weathering and terrestrial contamination after arrival. [More]

Dear EarthTalk: My husband and I want to start a garden this year. I really want to make compost from leftover food scraps and yard materials. He says it will attract unwanted animals, and refuses to agree to it. Is he right? If so, how do we deal with that issue in a green-friendly, non-lethal way? --Carmen Veurink, Grand Rapids, Mich.

The stark institutional isolation prevalent in the orphanages of some countries might have mostly melted away decades ago, but many babies and young children all over the world still grow up in environments where touch and emotional engagement are lacking. Many children who have not had ample physical and emotional attention are at higher risk for behavioral, emotional and social problems as they grow up.  [More]

The President's Cancer Panel on Thursday reported that "the true burden of environmentally induced cancers has been grossly underestimated" and strongly urged action to reduce people's widespread exposure to carcinogens .

Law enforcement was able to thwart an attempt to set off an explosion in the middle of New York City's Times Square on May 1 thanks to the quick thinking of a T-shirt vendor who noticed smoke coming from a parked SUV. Unfortunately, the signs that a bomb is nearby are often more subtle, detectable only at a microscopic level. [More]

An off-kilter body clock can throw off our sleep-wake cycle, eating habits, body temperature and hormones--and mounting evidence suggests a malfunctioning clock may also underlie the mood cycles in bipolar disorder.

In a new study led by psychiatrist Alexander Niculescu of Indiana University, researchers found that children with bipolar disorder were likely to have a mutated RORB gene, which codes for a protein crucial to circadian clock function. The team’s previous work identified alterations to this gene and other clock genes in animal models of the disorder. In the new study, the scientists compared the genomes of 152 bipolar kids with those of 140 typical kids. (Children were studied because their moods cycle more rapidly than the moods of bipolar adults, and a quicker cycle suggests a stronger connection to the circadian clock.) The team found that the bipolar children were more likely to have one of four alterations to RORB , and the investigators suspect the mu­tations prevent the body from producing the correct amount of the pro­tein to support normal clock function. [More]

The long and divisive fight over U.S. health care reform exposed basic weaknesses in the processes of governance. As is so often true in American politics these days, politicians and lobbyists kept complex subjects to themselves, pushing expert discussion and systematic public debate to the sidelines. Although the final legislation expands coverage, and I favor it for that reason, it falls far short of the changes we need to lower costs and improve health outcomes.

During 14 months of debate over health care, the administration did not put forward a clear, analytical policy white paper on the aims, methods and expected results of the proposed reforms. Only the Congressional Budget Office’s budget scoring of legislative proposals was even partly systematic; no comparable independent analysis exists on other substantive issues. The actual health consequences of the legislation were never reviewed or debated coherently.

By Jeffrey Jones and Jeff Mason

HOUSTON (Reuters) - U.S. regulators exempted BP Plc from a detailed environmental review of the exploration project that ultimately resulted in the deadly Gulf of Mexico explosion and subsequent oil spill, documents show.

Oh, so close. Just one more try. [More]

By Alla Katsnelson

A computer model proposes a solution to a long-standing mystery in HIV research -- why a small percentage of people infected with the virus never develop full-blown AIDS. [More]

Vast amounts of research on postpartum depression have focused on difficulties facing new mothers, and studies of adult depression have focused on individual struggles. Depression in mothers with children over the age of six months, however, is less discussed but exceedingly common. At least 12 percent of women in any given year--many of whom are mothers--and 20 percent of disadvantaged mothers have depressive symptoms. [More]