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Satellites the size of a loaf of bread to study space weather

Thu, 02 Oct 2008 08:31:00 -0400

Researchers and students from the University of Michigan in the US will design and build a satellite about the size of a loaf of bread, which will be deployed to study space weather.

Undergraduate and graduate students will be heavily involved in this Radio Aurora Explorer (RAX) project, led by the University of Michigan (U-M) and SRI International, a California-based independent research and technology development organization.

This CubeSat, as it’s called, will be the first free-flying spacecraft built in part by U-M students.

Members of the Student Space Systems Fabrication Laboratory (S3FL), which is an organization that gives students practical space systems design and fabrication experience, will play an important role.

CubeSats, developed about five years ago, are approximately four-inch cube-shaped devices that launch from inside a P-Pod, a special rocket attachment that was developed by California Polytechnic State University and Stanford University.

There is a growing interest in CubeSats as they offer relatively inexpensive and simpler access to space.

The RAX satellite will essentially be made of three CubeSats.

The RAX will measure the energy flow in the ionosphere, the highest part of Earth’s atmosphere where solar radiation turns regular atoms into charged particles.

Disturbances in the ionosphere can affect earth-to-space communications such as GPS signals, digital satellite television and voice and data transmission systems including Iridium and Globalstar.

“This project will help us better understand space weather processes, how the Earth and Sun interact, and how this weather produces noise in space communication signals — noise that translates to lower quality telecommunications capabilities and error in GPS signals,” said James Cutler, assistant professor in the Department of Aerospace Engineering and a principal investigator on the project.

The RAX satellite will act as a receiver that will pick up signals from a ground radar transmitter. These radar pulses will reflect off disturbances, or space weather phenomena, in the ionosphere.

RAX is scheduled for launch in December 2009.

RAX is scheduled to be the first in a series of CubeSat missions funded by the NSF (National Science Foundation) to study space weather phenomenon. (ANI)

Infrared echoes give clues to supernova''s first moments

Thu, 02 Oct 2008 08:31:00 -0400

Using data from NASA''s Spitzer Space Telescope, scientists have determined that hot spots near the shattered remains of an exploded star are echoing the blast''s first moments.

According to Eli Dwek of NASA''s Goddard Space Flight Center in Greenbelt, Maryland, and Richard Arendt of the University of Maryland, Baltimore County, these echoes are powered by radiation from the supernova shock wave that blew the star apart some 11,000 years ago.

"We''re seeing the supernova''s first flash," Dwek said.

Other Spitzer researchers discovered hot spots near the Cassiopeia A supernova remnant and recognized their importance as light echoes of the original blast.

Dwek and Arendt used Spitzer data to probe this hot dust and pin down the cause of the echoes more precisely.

Six knots of silicate dust near the remnant show temperatures between -280 degrees and -190 degrees Fahrenheit. Although this might seem frigid by Earthly standards, such temperatures are downright hot compared to typical interstellar dust.

Scientists have shown that the only event that could make the grains this hot is the powerful and short-lived pulse of ultraviolet radiation and X-rays that heralded the death of the star.

The flash was a hundred billion times brighter than the sun but lasted only a day or so.

"They''ve identified the precise event during the demolition of the star that produces the echo we see," said Michael Werner, the Project Scientist for Spitzer at NASA''s Jet Propulsion Laboratory in Pasadena, California.

Light from the explosion reached Earth in the 17th century, but no one noticed. The Spitzer find gives astronomers a second chance to study the supernova as it unfolds.

Although the explosion originally escaped detection, its aftermath - a hot, expanding gas cloud known as Cassiopeia A (Cas A), is one of the best-studied supernova remnants.

The blast zone lies 11,000 light-years away in the constellation Cassiopeia.

Evidence for a flash associated with this "shock breakout" existed only in computer simulations until January 9, 2008.

That''s when NASA''s Swift satellite detected a 5-minute-long X-ray pulse from galaxy NGC 2770. A few days later, a new supernova - designated SN 2008D - appeared in the galaxy.

The infrared echoes from Cas A arise from dust clouds about 160 light-years farther away than the remnant.

The supernova''s initial radiation pulse expands through space at the speed of light, then encounters the clouds and heats their dust grains. The dust, in turn, reradiates the energy at infrared wavelengths.

The breakout radiation took 160 years to reach the clouds and, once heated, the dust''s infrared energy had to make up the same distance.

The researchers plan to use the echoes to paint an intimate portrait of the explosion, the star, and the immediate environment. (ANI)

Shade trees can protect coffee crops from climate change

Thu, 02 Oct 2008 08:29:00 -0400

Researchers from University of Michigan suggest that shade trees can protect coffee crops from ravages of climate change.

With the increase in coffee production in recent decades the crop has become more vulnerable to higher temperatures and changes in precipitation.

However, the new study led by Brenda B. Lin, Ivette Perfecto has revealed that shade trees could improve coffee crop’s resistance to temperature and precipitation extremes triggered by climate changes.

The researchers also claimed that this procedure could be applicable to other economically important crops, including cocoa and tea.

In an effort to boost production, growers have increased their use of pesticides and relied less on shade trees, but the evidence suggests that these trends make the crop more susceptible to weather events. The benefits of shade trees appear greater in more marginal growing areas.

Lin and her colleagues urge further efforts to determine where a return to more traditional agroforestry techniques is likely to protect the livelihoods of farmers threatened by climate change.

The article is published in the October issue of BioScience. (ANI)

Early depression, anxiety treatment may cut relapse risk

Thu, 02 Oct 2008 08:24:00 -0400

Early treatment with antidepressant and anti-anxiety medication can significantly reduce relapse risk in future, says a new study by University of Alberta.

The study led by researcher Ian Colman focused on the long-term effects of taking antidepressants or anti-anxiety medications.

The team studied a group of 200 people who were diagnosed with either depression or anxiety. Of that group, 45 were on medication.

The team assessed their mental health in 1989 through a series of questions in a survey asking about their illness and what, if any, treatments they were on. Ten years later the group took a similar questionnaire.

The study showed that those who were not using antidepressants or anti-anxiety medications were three times more likely to be suffering from depression or anxiety 10 years later.

"This is a significant find," said Colman.

"What this tells us is that, if people get treated initially, they are less likely to have a relapse in the future.

Colman said that depression and anxiety have a stigma attached to them and that people are often afraid to admit they have a mental disorder. But he hopes this new information will help people realize the long-term benefits of getting help right away. (ANI)

Now, a revolutionary fold-away bathroom for small flats

Thu, 02 Oct 2008 08:23:00 -0400

Keeping small flats in mind, a Brit designer has developed the world''s first fold-away bathroom.

The 9,000 pounds device, which features two showers and a lavatory, is the work of award-winning designer Paul Hernon, of Huddersfield.

The space-saving Vertebrae - named after the human spine - stacks a sink, water cistern and shower-head into one 8ft steel column.

"I did lots of research and it became obvious to me that bathroom space was decreasing, particularly in apartments,” the Telegraph quoted him, as saying.

"I have created an intriguing but functional and simplistic space-saving bathroom by stacking the contents of a bathroom on top of one another. It is designed to utilise vertical space instead of horizontal floor space. It is quick to assemble and easy to maintain - all you need is a wet room to put it in.

"I think it pushes the boundaries of anything that has been done before. People who have seen it are completely blown away," he added.

The two showers, one for adults and one for kids, both rotate 180 degrees while the other units all rotate a full 360 degrees.

They all twist around a steel column, which contains all the piping, and each part simply pushes out when it is required.

The 38-year-old designer said that his creation could fit into a smaller space than a traditional bathroom, meaning architects could design smaller bathrooms and free up more space for other rooms.

However, he cautioned that the Vertebrae weighs 150 kilos, or more than 23 stone, and that householders might have to reinforce their bathroom floor before having it fitted.

The fold-away bathroom is expected to go on sale in 2009. (ANI)

Chernobyl explosion affected Sweden more than Poland

Thu, 02 Oct 2008 08:22:00 -0400

Researchers from Case Western Reserve University in Cleveland, Ohio, have tracked the Chernobyl fallout to reveal that much more plutonium was found in the Swedish soil at a depth that corresponded with the nuclear explosion than that of Poland.

When a reactor in the Chernobyl nuclear power plant exploded in 1986 in what was then the Soviet republic of Ukraine, radioactive elements were released in the air and dispersed over the Soviet Union, Europe and even eastern portions of North America.

More than 20 years later, researchers from Case Western Reserve University traveled to Sweden and Poland to gain insight into the downward migration of Chernobyl-derived radionuclides in the soil.

Among the team’s findings was the fact that much more plutonium was found in the Swedish soil at a depth that corresponded with the nuclear explosion than that of Poland.

Radionuclides occur in soil both from natural processes and as fallout from nuclear testing.

Gerald Matisoff, chair of the department of geological sciences at Case Western Reserve University, Lauren Vitko, field assistant from Case Western Reserve, and others took soil samples in various locations in the two countries, measuring the presence and location of cesium, plutonium, and lead.

By looking at the magnitude of the radioactive fallout, how fast it moved down into the soil profile and how quickly it eroded and is transported by sediment, Matisoff’s research helps shed light on two fronts.

The first is dealing with the public health ramifications, studying such issues as food chain transfer, exposure and cleanup as well as understanding the geologic aftereffects.

The second is developing an understanding of the differentiation of radioactive elements from a one-time event like Chernobyl and those of fallout created by atmospheric nuclear weapons testing conducted in the 1960s.

Soil samples collected by Matisoff’s team reveal insights based on several conditions, such as how the radionuclides were delivered to the soil, whether from a one-time event like the Chernobyl disaster or from atmospheric bomb testing.

It also reveals the half-life of the radionuclides and whether they were absorbed more heavily onto clay particles or organic materials; and the types of soil which may keep the particles at the surface or allow them to permeate to levels below the surface.

As the team examined a range of soil types from the two countries, they found a spike in 239, 240Pu in Sweden’s soil at a depth that coincides with the Chernobyl disaster, yet no similar blip in Poland’s soil.

Meteorological research showed that it rained in Sweden while the radioactive cloud was over that country.

Leeched of much of its radionuclides, much less plutonium fell on Poland when the cloud later crossed over its borders. (ANI)

Teen insomniacs at ‘increased depression, substance abuse risk’

Thu, 02 Oct 2008 08:21:00 -0400

Teenagers with insomnia are at an increased risk of developing depression and substance abuse problems in adolescence and young adulthood, a new study has found.

The study showed that adolescent insomniacs were also at an increase the risk of suicide ideation and attempts, and the use of alcohol, cannabis and other drugs such as cocaine.

The research involved 4,494 adolescents between 12 and 18 years of age at the beginning of the study, and 3,582 young adults between the ages of 18 and 25 years in a six-to-seven year follow up.

The findings revealed that adolescents who had symptoms of insomnia were 2.3 times more likely to develop depression in early adulthood than adolescents without symptoms of insomnia.

Moreover, the insomnia group was more likely to use alcohol, cannabis, and non-cannabis drugs, and was more likely to suffer have suicidal thoughts, and suicide attempts, after excluding participants who suffered from these specific psychopathologies at baseline.

Independently of insomnia status, males were significantly more likely to endorse alcohol use, cannabis use, and the use of other drugs, while females were twice as likely to develop depression.

"Previous research in adults has found similar results to this study," said principal investigator and lead author Brandy M. Roane, MS, a doctoral student at the University of North Texas.

"The current study suggests adolescents with insomnia are more prone to developing mental disorders, specifically depression," she added.

The study appears in the journal Sleep. (ANI)

‘Adolescents affiliation with delinquent peers tied up in the genome’

Thu, 02 Oct 2008 08:20:00 -0400

Adolescent males who possess a certain type of variation in a specific gene are more likely to develop affinity with delinquent peers, says a new study.

In a landmark study, a research team led by Florida State University criminologist Kevin M. Beaver has established a link between affinity for antisocial peer groups and a particular variation (called the 10-repeat allele) of the dopamine transporter gene (DAT1).

"This research is groundbreaking because it shows that the propensity in some adolescents to affiliate with delinquent peers is tied up in the genome," said Beaver, an assistant professor in the FSU College of Criminology and Criminal Justice.

However, the study also suggests that family environment plays a crucial role in this association.

The analysis of family, peer and DNA data from 1,816 boys in middle and high school found that the association between DAT1 and delinquent peer affiliation applied primarily for those who had both the 10-repeat allele and a high-risk family environment, the environment marked by a disengaged mother and an absence of maternal affection.

On the other hand, adolescent males with the very same gene variation who lived in low-risk families, one with high levels of maternal engagement and warmth showed no statistically relevant affinity for antisocial friends.

"Our research has confirmed the importance of not only the genome but also the environment," Beaver said.

"We can only hypothesize why we saw the effect of DAT1 only in male adolescents from high-risk families," said Beaver, who will continue his research into the close relationship between genotype and environmental factors -- a phenomenon known in the field of behavioural genetics as the "gene X environment correlation."

"Perhaps the 10-repeat allele is triggered by constant stress or the general lack of support, whereas in low-risk households, the variation might remain inactive," he said.

"Or it''s possible that the 10-repeat allele increases an adolescent boy''s attraction to delinquent peers regardless of family type, but parents from low-risk families are simply better able to monitor and control such genetic tendencies," he added.

The study appears in the Journal of Genetic Psychology. (ANI)