stars 883.sta.44 Louis J. Sheehan

Brittle stars may end up with less star power as greenhouse gases change ocean chemistry.

As human activity increases concentrations of carbon dioxide in the air, ocean chemistry is changing, says Hannah L. Wood of Plymouth Marine Laboratory in England. The pH of seawater, now around 8.1, is dipping closer to the acidic side, changing the supplies of various forms of carbon that sea creatures like corals and brittle stars need to form the hard parts of their bodies. http://louis3j3sheehan3esquire.wordpress.com/

In a lab test, the pink brittle star Amphiura filiformis still managed to capture the carbon and calcium it needs to regenerate arms in lowered pH water, Wood says. “That’s against the trend” of earlier predictions, she says. Biologists had expected trouble for calcifying marine life as seawater pH declines.

“There’s a trade-off,” Wood says. The brittle star’s new arms grew with extra calcification but also had less muscle. In water adjusted to pH 7.7, which a gloomy scenario predicts for the oceans as soon as 2100, the brittle star arms had one-fifth to one-quarter of their usual brawn. http://louis3j3sheehan3esquire.wordpress.com/

In the modified seawater, brittle stars nearly doubled their oxygen use. “It’s the equivalent of us breathing heavily,” Wood says.

“The main message is we need to look beyond calcification,” she says. The study will appear in an upcoming Proceedings of the Royal Society B.

“The most significant aspect here, I think, is that the increased calcification rates may come at a cost to other processes,” says Gretchen Hofmann of the University of California, Santa Barbara. “We need to look more deeply into an organism’s physiology to really get the whole picture.”

77665

In the Amazon rainforests of Brazil, scientists have discovered a peculiar new species of ant. The insect has no eyes. Its body is pale. And its fanglike mouthparts are longer than the rest of its head.

If you happened to cross paths with the bizarre ant, you might imagine that it belongs on another planet. Even its name — Martialis heureka — playfully suggests that it came from Mars.

But Martialis heureka lives on Earth. And the creepy-crawly discovery is forcing researchers to rethink what they know about the history of ants on our planet.

Ancient insectScientists looked at the ant's genes to find out where it fits in the ant family tree. They showed that the odd ant may come from the earliest branch of the ant family that still has living members.C. Rabeling, M. Verhaagh

Christian Rabeling, from the University of Texas at Austin, discovered the new species amid the fallen leaves of the rainforest. But he did more than just notice how weird the ant looks. He also analyzed its genetic material, or DNA.

Comparing DNA among species can give scientists insights into family trees: The more DNA two species share in common, the more closely related they are, and the more recently they split off from a common ancestor.

Rabeling’s DNA analysis of Martialis heureka showed that the species is only distantly related to other ant species. It is so distant, in fact, that it belongs in a separate subfamily — a broader grouping than a species or even a genus. The last time scientists found a new subfamily of living ants was in 1923, say the discoverers.

The DNA analysis also suggests that Martialis heureka appeared on Earth earlier than any other ant living here today. And observations suggest that the ant lives underground: Paleness and blindness are two major clues.

Some of the other oldest known ant species also live underground. So now, scientists are trying to figure out whether ants first evolved underground, or if they evolved above ground and then went under.http://Louissheehan.BraveDiary.com

Corrie Moreau, an ant specialist at the Field Museum in Chicago, saw a picture of the new creature. “It’s an incredibly bizarre-looking ant … which for ant biologists is really exciting,” she says. A few other ant species have at least one of Martialis heureka’s weird features, she says. But none share them all.

So far, Rabeling has collected only one ant from the new species. Finding more specimens, he hopes, will help us better understand the science and history of ants on Earth.

सोलर-powered

http://louis-j-sheehan.नेट। In an experiment that tested technology that could one day be used to transmit solar energy from satellites to Earth, researchers beamed solar energy from one Hawaiian island to another, across a distance of 92 miles. The $1 million experiment was sponsored by the Discovery Channel, which aired an episode about the technology on its Project Earth show on Friday.

The experiment was intended as a proof of concept for an ambitious proposal that calls for huge arrays of solar panels to orbit the Earth, collecting pristine solar radiation, free from the day/night cycles, weather and atmospheric effects that limit solar radiation down on the ground. The energy collected will be “beamed” down to power stations on the surface, either by microwave (or an alternative system, by laser) — and then distributed as normal power across the grid [Discovery Channel]. Backers of this space-based solar technology say the potential benefits are enormous; the non-profit National Space Society says that the sun puts out billions of times more energy than our planet’s population uses.

This experiment, however, operated on a very small scale. Although the amount of power sent, 20 watts, is barely enough to power a small compact fluorescent light bulb, and most of it was lost in transmission, the system was limited by the budget not the physics [Wired News]. The experiment’s leader, former NASA executive and physicist John Mankins, said that if they had been able to afford more solar panels and better receivers they could have boosted efficiency considerably.

Solar-powered satellites won’t just be appearing on TV; both the U.S. military and the Japanese space agency are working on projects of their own. [T]he Air Force Academy recently announced plans for a small demonstration satellite that would beam down a meager, but still significant, 0।1 watts of solar power. “Our vision is to build the world’s first-ever space-based solar power system to light a single bulb on Earth and in so doing light the path for business to follow,” said Col. Michael “Coyote” Smith of the Air Force. [Meanwhile, Japan’s] goal is to launch a geostationary satellite by 2030 that could supply 500,000 homes on Earth with a gigawatt of power. http://louis-j-sheehan.net

condom

Uganda has shown remarkable progress against HIV, the AIDS virus, according to an analysis of health data. Since the early 1990s, HIV cases in Uganda have dropped by more than two-thirds, a decline not seen in neighboring countries. For example, the HIV-infection rate among Ugandan men drafted into the military fell from nearly 19 percent in 1991 to 4 percent in 2002.

Condom use in Uganda increased somewhat during the 1990s, but not faster than it did in nearby countries. Uganda's gains in the fight against AIDS are more likely due to an initiative started in the 1980s by public health officials, who sounded a clear warning about HIV that alerted people to the risks of casual sex, researchers say in the April 30 Science. The message reached the community level through local networks of chiefs, churches, and even musicians, says epidemiologist Daniel Low-Beer of the University of Cambridge in England, a coauthor of the study.

The resulting change in people's sexual behaviors in Uganda is now evident.

Between 1989 and 1995, Uganda experienced a three-fifths decline in people reporting casual sexual partnerships. Also, the proportion of unmarried women who reported having sex dropped from 53 percent to 16 percent.

murals

Tiny magnetic particles found in the pigments of some ancient Mexican murals record the direction of Earth's magnetic field when the paint dried, a phenomenon that could help archaeologists determine the age of frescoes throughout Mexico and Central America। http://louis-j-sheehan.com

The red pigments in murals painted by the artists of pre-Columbian civilizations in the New World often contain bits of magnetite, an iron oxide mineral, says Avto Goguitchaichvili of the National Autonomous University of Mexico in Mexico City। When the paints were wet, those particles were free to rotate and align themselves with Earth's magnetic field, becoming locked in that position as the paints dried. http://louis-j-sheehan.com

Goguitchaichvili and his colleagues analyzed 28 paint samples from murals of known ages at four temples near Mexico City. Data from these murals, which were painted between A.D. 200 to A.D. 1200, reveal the slow changes of orientation of Earth's magnetic field over that period. That knowledge, in turn, permits the age of other murals to be deduced from the alignment of their magnetite particles. The scientists describe their findings in the June 28 Geophysical Research Letters.

The paint-analysis technique may provide an inexpensive alternative to other methods of determining the age of archaeological sites, such as radiometric dating of artifacts. Louis J. Sheehan, Esquire

grief

Severe grief may be a unique mental disorder, according to a new psychiatric study. People who exhibit prolonged, debilitating grief after a loved one's death often improve markedly upon receiving a novel type of psychotherapy that focuses on finding ways to adjust to the loss, says a team led by psychiatrist Katherine Shear of the University of Pittsburgh School of Medicine.http://louis-j-sheehan.biz

Current psychiatric diagnoses don't include what these investigators refer to as complicated grief. In Shear's view, this condition becomes apparent 6 months or more after the death of a loved one. Symptoms consist of disbelief regarding the death, anger and bitterness over the death, intense yearning for the deceased, and intrusive thoughts about how the loved one died.Louis J. Sheehan

The researchers developed a form of psychotherapy for complicated grief that calls for repeatedly confronting one's negative reactions to a loss as well as identifying and working toward personal goals. This treatment offers better, faster help for complicated grief symptoms than does a standard form of psychotherapy that targets grief-related depression and social problems, Shear and her coworkers report in the June 1 Journal of the American Medical Association.http://louis-j-sheehan.biz

The investigators randomly assigned 95 adults with complicated grief symptoms to one or the other of the two treatments। After 16 sessions, half of the patients receiving the new treatment showed substantial improvement, compared with only one-quarter of those getting standard psychotherapy. Signs of improvement, such as articulating new goals, typically appeared after four sessions of the new treatment and after eight sessions of standard psychotherapy. Louis J. Sheehan

patients

Preliminary evidence indicates that people can quell either temporary or chronic physical pain by learning to use their minds to reduce activity in a key brain area.

Brain-imaging technology now enables individuals to use mental exercises to control a neural region that contributes to pain perception, say neuroscientist Sean C। Mackey of Stanford University and his colleagues। http://Louis2J2Sheehan2Esquire.US

Both healthy volunteers and chronic-pain patients "learned to control their brains and, through that, their pain," Mackey holds। "However, significantly more testing must be done before this can be considered a treatment for chronic pain।" http://Louis2J2Sheehan2Esquire.US

The new findings appear in the Dec. 20 Proceedings of the National Academy of Sciences.

Mackey's team studied 32 healthy volunteers, ages 18 to 37. First, each volunteer reported when an adjustable heat pulse applied to a leg produced pain that he or she rated as 7 out of 10, with 10 being equivalent to "the worst pain imaginable." Brain imaging of participants, using a functional magnetic resonance imaging (fMRI) scanner, showed that this level of pain was accompanied by pronounced blood flow—a sign of intense neural activity—in an area called the rostral anterior cingulate cortex.

Eight of the volunteers then underwent brain training. Each reclined in an fMRI machine that visually displayed activity changes in the person's rostral anterior cingulate cortex. A virtual flame dimmed as activity fell and brightened as activity surged.

While watching this display for 39 minutes, participants tried various mental strategies both to increase and to decrease their brain activity during brief periods of heat-pulse application. The experimenters suggested tactics such as focusing attention away from the pain.

By the end of the training session, the volunteers had learned to raise or lower activity in the critical brain area, the researchers say. The eight volunteers rated pain much higher during robust anterior cingulate cortex activation than during periods of lesser activity in that region.

No such brain-related pain effects occurred for the remaining 24 participants, who were instructed to change their brain activity when they were outside the fMRI machine or in the machine but receiving no feedback, when they received feedback from brain areas unrelated to pain, or when they viewed someone else's pain-related brain activity.

Next, eight chronic-pain patients completed anterior-cingulate-cortex training. Afterward, each reported much less pain—often less than half as much as usual—while he or she mentally quelled the region's activity.

Another four chronic-pain patients used physiological feedback—so-called biofeedback—to learn to control their heart rate, skin conductance, and breathing. None succeeded in lessening pain.

Neuroscientist Gary H. Duncan of the University of Montreal calls the new study "a landmark contribution of brain imaging to pain research." It demonstrates that self-control over activity in a specific brain region is possible, paving the way for explorations of neural function far beyond the treatment of chronic pain, he says.