Search This Blog

Wednesday, August 8, 2007

Space shuttle Endeavour on Wednesday in preparation for its evening liftoff.

With good weather predicted for launch time, NASA started fueling space shuttle Endeavour on Wednesday in preparation for its evening liftoff.

The space agency began pumping more than 500,000 gallons of supercold liquid hydrogen and liquid oxygen into the ship's tank shortly after 8 a.m. The process was expected to take about three hours, leaving plenty of time before the scheduled 6:36 p.m. launch, which will take former schoolteacher Barbara Morgan into space.

Forecasters predicted an 80 percent chance that the weather will be favorable for liftoff.

Morgan, who was Christa McAuliffe's backup on Challenger two decades ago, and her six crewmates are slated to spend two weeks at the international space station.

Their mission continues construction on the orbiting outpost. The crew is to attach a new truss segment to the space station, replacing a gyroscope that helps control the station's orientation and delivering 5,000 pounds of cargo.

If the mission is extended from 11 days to 14 days, a decision that won't be made until the mission is well under way, the astronauts will add a fourth spacewalk to the planned three to install protective panels to stop debris from hitting the station.

Morgan went back to teaching after the Challenger disaster but continued her NASA-related speaking engagements. In 1998, she became the first teacher to join the astronaut corps, trained to conduct tasks on a mission, rather than be a guest on a flight as McAuliffe was.

While in space, Morgan plans to answer questions from schoolchildren in Idaho, and if the mission is extended, from Virginia and Massachusetts as well.

Endeavour was initially scheduled to lift off Tuesday but was delayed for a day because NASA had to replace a leaky valve in the crew cabin.

Technorati :

How Tidal Power Plants Work

How Tidal Power Plants Work

There are three basic ways we can harnass tidal power .
The power of the rise and fall of the sea level or tidal power, can be harnessed to generate electricity.

Tidal Power
Tidal power traditionally involves erecting a dam across the opening to a tidal basin. The dam includes a sluice that is opened to allow the tide to flow into the basin; the sluice is then closed, and as the sea level drops, traditional hydropower technologies can be used to generate electricity from the elevated water in the basin. Some researchers are also trying to extract energy directly from tidal flow streams.
The energy potential of tidal basins is large - the largest facility, the La Rance station in France, generates 240 megawatts of power. Currently, France is the only country that successfully uses this power source.

Sponsored Links
Find Invention Patenting, Promotion & Trademarking Assistance Here.

Power plants Jobs
Immediate Requirement in Companies. Submit Your Resume Free. Now!

Wind Power resources
Application notes, reports, policy & new technology on wind power
French engineers have noted that if the use of tidal power on a global level was brought to high enough levels, the Earth would slow its rotation by 24 hours every 2,000 years.
Tidal energy systems can have environmental impacts on tidal basins because of reduced tidal flow and silt buildup.

3 Ways of Using the Tidal Power of the Ocean
There are three basic ways to tap the ocean for its energy. We can use the ocean's waves, we can use the ocean's high and low tides, or we can use temperature differences in the water.

1 Wave Energy
Kinetic energy (movement) exists in the moving waves of the ocean. That energy can be used to power a turbine. In this simple example, (illustrated to the right) the wave rises into a chamber. The rising water forces the air out of the chamber. The moving air spins a turbine which can turn a generator.
When the wave goes down, air flows through the turbine and back into the chamber through doors that are normally closed.

This is only one type of wave-energy system. Others actually use the up and down motion of the wave to power a piston that moves up and down inside a cylinder. That piston can also turn a generator.

Most wave-energy systems are very small. But, they can be used to power a warning buoy or a small light house.

2 Tidal Energy
Another form of ocean energy is called tidal energy. When tides comes into the shore, they can be trapped in reservoirs behind dams. Then when the tide drops, the water behind the dam can be let out just like in a regular hydroelectric power plant.
In order for this to work well, you need large increases in tides. An increase of at least 16 feet between low tide to high tide is needed. There are only a few places where this tide change occurs around the earth. Some power plants are already operating using this idea. One plant in France makes enough energy from tides to power 240,000 homes.

3 Ocean Thermal Energy
The final ocean energy idea uses temperature differences in the ocean. If you ever went swimming in the ocean and dove deep below the surface, you would have noticed that the water gets colder the deeper you go. It's warmer on the surface because sunlight warms the water. But below the surface, the ocean gets very cold. That's why scuba divers wear wet suits when they dive down deep. Their wet suits trapped their body heat to keep them warm.
Power plants can be built that use this difference in temperature to make energy. A difference of at least 38 degrees Fahrenheit is needed between the warmer surface water and the colder deep ocean water.

Using this type of energy source is called Ocean Thermal Energy Conversion or OTEC. It is being used in both Japan and in Hawaii in some demonstration projects

Technorati : :
Ice Rocket :
Flickr :
Zooomr :
Buzznet :

NASA Space Telescope Gives Scientists Depth Perception

NASA Space Telescope Gives Scientists Depth Perception

Astronomers now have a new "eye" for determining the distance to certain mysterious bodies in and around our Milky Way galaxy. By taking advantage of the unique position of NASA's Spitzer's Space Telescope millions of miles from Earth, and a depth-perceiving trick called parallax, they were able to pin down the most probable location of one such object. The findings will ultimately help astronomers better understand the different components of our galaxy.

"Forty years ago a visionary astronomer named Dr. Sjur Refsdal theorized that dark bodies could be located using parallax and a space telescope," said Andrew Gould of Ohio State University, Columbus, Ohio, who led the project. "It is truly remarkable that we have been able to prove him right with this Spitzer observation."

Spitzer is the only telescope that orbits the sun behind Earth, and is the farthest telescope from us with the ability to study distant stars. Currently, Spitzer is about 40 million miles (70 million kilometers) away from Earth. It will continue to drift farther and farther away at a rate of about 10 million miles (15 million kilometers) per year.

This great distance gives astronomers a great advantage. They can use Spitzer in the same way that a human brain uses two eyes to tell how far away objects are, a principle called parallax. With two eyes, we have two perspectives, which our brains combine to give us depth perception. In space, Spitzer acts as one eye, while a ground-based telescope acts as the other. With two very wide cosmic eyes, astronomers can determine the location of bodies within and just outside our galaxy.

Gould and his team are the first to use Spitzer to perform this astronomical feat. Their goal was to determine whether a previously identified dark matter candidate, called a massive compact halo object, or "Macho," is within our galaxy and contributing to its overall weight.

Our galaxy is heavier than it looks, with at least 80 percent of its mass consisting of mysterious, invisible dark matter. A large fraction of this dark matter is the exotic kind, different from the ordinary matter that makes up the familiar world around us. The rest might be so-called machos, which are ordinary-matter dark bodies that lurk in our galaxy's halo, the region that sits above and below its spiral disk. They are thought to be a combination of black holes, very faint stars and isolated planets.

Several suspected machos have been discovered in the past through a technique called microlensing, in which the dark bodies' gravity causes light from a passing background star to bend and brighten. But astronomers do not know whether these candidates are indeed machos in the galaxy halo, or other, non-macho objects just outside the Milky Way in small satellite galaxies. By pinpointing the location of the candidates, astronomers will learn whether they are in the halo and thus machos. This information, in turn, will help them figure out how much machos contribute to the total mass of our galaxy.

OGLE-2005-SMC-001 is one such macho candidate. It was first discovered by Andrzej Udalski, of the Optical Gravitational Lens Experiment (OGLE), and Warsaw University Observatory, Warszawa, Poland. Udalski and colleagues noticed that the dark object was causing a passing, background star to brighten. Gould and his team quickly sprang to action, following up with Spitzer observations of the short-lived event.

The data from both telescopes, or "eyes," were then combined and modeled through a series of complicated equations. The results indicate with 95 percent probability that OGLE-2005-SMC-001 is dark matter in our galaxy's halo and therefore a part of its overall mass.

In addition, the data show that OGLE-2005-SMC-001 consists of two bodies circling around each other. Gould and colleagues think the objects could be a pair of black holes, a very rare sighting in our universe. However, there is a small chance this feature is actually just a regular pair of orbiting stars in a neighboring, satellite galaxy.

"It will be very exciting to locate and measure the masses of more dark objects in the future by applying this technique. And we might finally be able to unravel the mystery of machos," said Subo Dong of Ohio State University, whose paper on OGLE-2005-SMC-001 has been accepted for publication in Astrophysical Journal. Dong presented the results today at a press conference, at the 210th meeting of the American Astronomical Society in Honolulu, Hawaii.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA.

Caffeine may help older women protect their thinking skills,

Caffeine may help older women protect their thinking skills, according to a study in Tuesday's issue of Neurology.
The study found that women age 65 and older who drank more than three cups of coffee or tea per day had less decline over time on memory tests than women who drank a cup or less of coffee or tea daily.
Karen Ritchie, a scientist with the French National Institute for Health and Medical Research, said that a better understanding of how caffeine affects the brain is needed "before we can start promoting caffeine intake as a way to reduce cognitive decline."
The four-year study involved 7,000 people. Compared with women who drank one cup or less of coffee a day, those who drank more than three cups were less likely to show as much decline in memory.
Ritchie said that researchers don't know why caffeine didn't show the same result in men.
DVDs to educate babies
may delay infant chatter Despite marketing claims, parents who want to give their infants a boost in learning language probably should limit the amount of time they expose their children to DVDs and videos such as "Baby Einstein" and "Brainy Baby."
Rather than helping babies, the overuse of such productions may slow down infants 8 months to 16 months of age when it comes to acquiring vocabulary, say researchers at the University of Washington and Seattle Children's Hospital Research Institute.
The scientists found that for every hour a day spent watching baby DVDs and videos, infants understood an average of six to eight fewer words than infants who did not watch them. Baby DVDs and videos had no positive or negative effect on the vocabularies of toddlers 17 to 24 months of age.
The study is in today's issue of the Journal of Pediatrics. The four-year study involved 7,000 people. Compared with women who drank one cup or less of coffee a day, those who drank more than three cups were less likely to show as much decline in memory.
Ritchie said that researchers don't know why caffeine didn't show the same result in men.
DVDs to educate babies
may delay infant chatter Despite marketing claims, parents who want to give their infants a boost in learning language probably should limit the amount of time they expose their children to DVDs and videos such as "Baby Einstein" and "Brainy Baby."
Rather than helping babies, the overuse of such productions may slow down infants 8 months to 16 months of age when it comes to acquiring vocabulary, say researchers at the University of Washington and Seattle Children's Hospital Research Institute.
The scientists found that for every hour a day spent watching baby DVDs and videos, infants understood an average of six to eight fewer words than infants who did not watch them. Baby DVDs and videos had no positive or negative effect on the vocabularies of toddlers 17 to 24 months of age.
The study is in today's issue of the Journal of Pediatrics.

Inventor of the Week



The ease with which today's average consumer can engage in extremely robust, high-quality desktop publishing can be credited largely to the work of John Warnock and Charles "Chuck" Geschke, who in 1982 founded Adobe Systems, Inc., to deliver the programming language known as PostScript to printer and computing device makers.

Warnock and Geschke first met while working for the research organization Xerox PARC (Palo Alto Research Center), where Warnock, under the direction of Geschke, developed a language dubbed "Interpress" to enable Xerox printers to talk to computers. The pair's mutual frustration with Xerox PARC's unwillingness to commercialize the software inspired them to strike out on their own; today Adobe is arguably the most important firm in desktop publishing software worldwide and is worth nearly $3 billion.

Warnock was born on Oct. 6, 1940, in Salt Lake City, Utah. He attended the University of Utah, where he earned B.S. degrees in mathematics and philosophy; an M.S. in mathematics; and a Ph.D. in engineering and computer science. He joined IBM Corp. while pursuing his doctoral degree and left planning to complete his education and become a professor. A job in the computer center at Utah inspired in him a love of technology and an interest in the burgeoning personal computing industry. He worked for a time for Evans & Sutherland Computer Corp. and Computer Sciences Corp. before he accepted a post in graphics research at Xerox PARC; Geschke was the man who hired him.

Cleveland, Ohio, native Geschke was born on September 11, 1939. He earned a B.A. in classics and an M.S. in mathematics at Xavier University, followed by a Ph.D. in computer science from Carnegie Mellon in 1972. He joined Xerox PARC shortly after graduation; there he helped design the Mesa programming language and was charged in 1980 with forming a new laboratory focused on graphics and imaging research. He formed the Imaging Sciences Laboratory where he lead the development of Interpress, a device-agnostic printing protocol, working closely with Warnock.

At that time, personal computing devices were beginning to come to the marketplace for the first time. Printers were being developed, but these were of the dot-matrix variety, which produced results with extremely poor quality. Printing from computers was typically done using typesetting machines that cost upwards of $150,000, and production was labor-intensive.

While Xerox made Interpress its internal standard, the firm was not interested in licensing the technology to others. Warnock and Geschke believed that this was a tremendous missed-opportunity. They resigned from Xerox PARC in 1982 and created a new language from scratch to enable computers to communicate to printers exactly how text, images, and lines should appear on paper. They named their firm after a creek that ran behind Warnock's home.

Their original plan was to start a service business where they would provide printing services to businesses and consumers. Encouraged by their financiers, they moved toward a software development model and focused on making PostScript truly portable, based on Warnock's innovative algorithm for "hidden surface determination in computer graphics."

They caught the attention of Steve Jobs and Apple Computer, which bought a 19 percent stake in Adobe and agreed to use PostScript in its LaserWriter printer. That printer hit the market in 1985; a year later Texas Instruments released IBM-compatible PCs equipped with the PostScript protocol. Adobe held its initial public offering in 1986. By 1988, it had grown to an $83 million company.

Adobe expanded its offerings, adding Illustrator design software in 1987, Acrobat in 1993, and later Photoshop and Premiere. The company also created the Acrobat portable document format (PDF), which made it possible to transfer files between incompatible systems and keep the look consistent. Adobe remains an industry standard setter and continues to update and add to its product line.

Warnock held the position of Chairman, CEO and chief technical officer of Adobe Systems until 2001. He holds six patents and has been honored with numerous awards for his work, including the ACM Systems Award; the Bodleian Medal; and many others. He is also a fellow of the Association for Computing Machinery.

Geschke held the post of president of Adobe until 2000. His long list of awards includes the John W. Gardner Leadership Award and, with Warnock, the 2006 American Electronics Association's Medal of Achievement. As of this 2007 writing, Geshcke and Warnock continue to serve as co-chairmen of the board of Adobe Systems.

Technorati : :
Ice Rocket :
Flickr :
Zooomr :
Buzznet :

Astronomers Find Highly Elliptical Disk Around Young Star

24hoursnew :Astronomers using the Hubble Space Telescope and W. M. Keck Observatory have found a lopsided debris disk around a young star known as HD 15115. As seen from Earth, the edge-on disk resembles a needle sticking out from the star.

Astronomers think the disk's odd imbalanced look is caused by dust following a highly elliptical orbit about the star. The lopsided disk may have been caused by the gravity of planets sweeping up debris in the disk or by the gravity of a nearby star.

The observations were made by Paul Kalas, James Graham, and Michael P. Fitzgerald, all from the University of California at Berkeley. Their paper appeared in The Astrophysical Journal Letters.

"The lopsided disk presents a host of new challenges for theorists," said Kalas.

Debris disks are produced by dust from collisions among protoplanetary bodies, which are the building blocks of planets. These dusty disks can be affected by planets nearer to the star, much as Jupiter's gravity affects asteroids in the asteroid belt.

This discovery is consistent with models for planetary upheavals in our own solar system, where Neptune may have originally formed between Saturn and Uranus. Neptune was eventually kicked out to its present location by a gravitational dance between Saturn and Jupiter before their orbits stabilized. "Therefore, we speculate that if such a planetary upheaval were occurring around HD 15115 at the present time, it could explain the highly asymmetric disk," Kalas said.

This might happen through a powerful gravitational interaction between planets that kicks one or more planets into highly elliptical orbits, or even ejects them into interstellar space. When the planet's orbit becomes elliptical through a violent upheaval, the rest of the disk can be disturbed into an elliptical shape, according to Kalas.

Kalas also is studying whether the gravity of a star known as HIP 12545, located about 10 light-years from HD 15115, may have created the disk's lopsided shape due to a close encounter in the past.

Dusty disks are known to exist around at least 100 stars, but because of the difficulty in observing material within the glare of a star, less than a dozen have been studied closely.

HD 15115 and HIP 12545 are among nearly 30 stars that belong to the Beta Pictoris Moving Group. Moving groups are expanded clusters of stars believed to have a common birthplace and age that are traveling loosely together through space.

The dusty disk around HD 15115 was first inferred by observations at infrared wavelengths in 2000 and its existence confirmed in 2006 when the Hubble Space Telescope (HST) resolved the disk in reflected light for the first time. The disk was investigated further using Keck adaptive optics in 2006 and 2007.

"The disk was seen in the HST data, but its appearance was so extraordinary we could not be certain that it was real. It took follow-up observations at Keck to confirm that it was a real disk," Kalas said.


For more information, contact:

Dr. Paul Kalas
University of California, Berkeley, Calif.,
510-642-8285; or

Dr. Michael P. Fitzgerald
University of California,
Berkeley, Calif., 510-643-8530;

Technorati : , : ,
Ice Rocket : ,
Flickr : ,
Zooomr : ,
Buzznet : ,

New Study in Science Warns of Greenland’s Accelerating Glaciers

new study in science

East Greenland icebergs. Large numbers of bergs are calved each year from the fast-flowing terminus of Kangerdlussuaq Glacier, East Greenland. Iceberg production is a major form of mass loss from ice sheets.
[Image courtesy of J.A. Dowdeswell]

Photo of the calving front of Helheim Gletscher, southeast Greenland in May 2005 showing high calving activity associated with flow acceleration. This glacier is now one of the fastest moving glaciers in the world.
[Image courtesy of NASA Wallops/Sonntag]

ST. LOUIS - The amount of ice that Greenland's glaciers dump into the Atlantic Ocean has almost doubled in the last five years because glaciers are moving faster, according to a new Science study.

Rising surface air temperatures appear to be triggering the increases in glacier speed in the southern half of Greenland, the study's authors say. One result, they add, is that many estimates of Greenland's future contributions to sea-level rise could be too low.

This is the first study to incorporate recent changes in glacier velocity into estimates of the overall mass of ice being lost for nearly all of Greenland.

The findings, announced Thursday 16 February at the 2006 AAAS Annual Meeting in St. Louis, Mo. are scheduled to appear in the 17 February 2006 issue of the journal Science, which is published by AAAS.

"The behavior of the glaciers that dump ice into the sea is the most important aspect of understanding how an ice sheet will evolve in a changing climate," said Science author Eric Rignot from the Jet Propulsion Laboratory, California Institute of Technology in Pasadena, Calif. "It takes a long time to build and melt an ice sheet, but glaciers can react quickly to temperature changes."

Rignot expressed concern that the models now used to predict Greenland's ice loss and contribution to sea level rise are inadequate because they do not account for changes in the speed of outlet glaciers that flow into the sea.

Taking higher glacier speeds into account, the authors calculate that Greenland contributes about 0.5 millimeters per year to global sea level rise which currently stands at 3 millimeters per year. Recent increases in glacier speed on Greenland are responsible for more than two-thirds of Greenland's contribution to sea level rise, the authors say.

Since 1996, Southeast Greenland's outlet glaciers have been largely responsible for increases in overall glacier flow. After 2000, glaciers further north have also rapidly increased in speed, and the northward spread of warmer temperatures may be responsible, according to Rignot.

Over the last 20 years, the air temperature in southeast Greenland has risen by 3 Celsius degrees. The warmer temperatures increase the amount of melt water reaching the glacier-rock interface where it serves as a lubricant that eases glaciers' march to the ocean, the authors say.

"Climate warming can work in different ways, but generally speaking, if you warm up the ice sheet, the glacier will flow faster," said Rignot, who noted that the processes by which the glaciers accelerate are complex and not that well understood at present.

If warming continues, the recent trend toward faster moving glaciers in the southern half of Greenland may reach the glaciers in northwest Greenland, the authors say.


Read All About It!

For more AAAS news from the 2006 Annual Meeting in St. Louis, Mo., click here.


Using data from satellites capable of monitoring glacier movement from space, the researchers generated a glacier velocity map for nearly all of Greenland for 2000. By incorporating satellite measurements from 1996 and 2005, the researchers analyzed how glacier velocity has changed over the last 10 years. They combined this glacier velocity information with ice thickness estimates to calculate changes in Greenland's total annual ice loss and mass balance over the same period.

The Greenland Ice Sheet gains mass through snowfall and loses mass when ice melts, erodes or vaporizes off the surface, when ice breaks off and forms icebergs due to glacier flow, and when ice melts from the base of floating ice connected to glaciers.

Due to the recent speed up, more ice is being dumped into the sea. The component of ice loss due to glacier flow has increased from 50 cubic kilometers of ice loss per year in 1996 to 150 cubic kilometers of ice loss per year in 2005.

Understanding patterns of snow accumulation is also important for the overall picture of Greenland's role in sea level rise. Glaciers draining regions of Greenland that receive lots of snow, like the southeast and northwest, have the capacity for a greater contribution to sea level rise because more snow leads to more ice that can be dumped into the ocean.

When the researchers included findings from other groups on ice loss from glacier melting and ice accumulation from snowfall, they found that the Greenland Ice Sheet's overall mass loss has increased from 90 cubic kilometers of ice loss per year in 1996 to 224 cubic kilometers of ice loss per year in 2005.

The Greenland Ice Sheet is 1.7 million square kilometers, up to 3 kilometers thick and a little smaller than Mexico. If the Greenland Ice Sheet completely melted, it would raise global sea level by about 7 meters.

The mass balance of the great ice sheets of Greenland and Antarctica represents the largest unknown in predictions of global sea-level rise over the coming decades, writes the author of a related "Perspective" article who notes that the mass balance of large ice sheets can depend on the behavior of a small number of outlet glaciers.

"The southern half of Greenland is reacting to what we think is climate warming. The northern half is waiting, but I don't think it's going to take long," said Rignot, who added that he is already seeing northern glaciers hinting at a speed up in their march to the ocean.

Eric Rignot is at the Jet Propulsion Laboratory, California Institute of Technology in Pasadena, Calif. Co-author Pannir Kanagaratnam is at the University of Kansas in Lawrence, Kan. This work was performed at the Jet Propulsion Laboratory and the University of Kansas, Lawrence under a contract with NASA's Cryospheric Science Program.

The American Association for the Advancement of Science (AAAS), founded in 1848, is the world's largest general scientific society; it serves 262 affiliated societies and academies of science, reaching 10 million individuals. It is publisher of the journal Science, which has the largest paid circulation of any peer-reviewed general science journal in the world and an estimated total readership of 1 million. AAAS is a non-profit organization, with membership open to everyone. It fulfills its mission to "advance science and serve society" through initiatives in science policy; international programs; science education; communication and more. For the latest research news, log onto EurekAlert!, the premier science-news Web site, a service of AAAS

Technorati :

Study sees U.S. retirement wealth up sharply by 2040

24hoursnews:The average value of Americans' 401(k) plans will be substantially higher in real terms by the year 2040 even if stock market returns fall short of their historical values, according to new research by a team of economists from MIT, Harvard and Dartmouth.

In a study published this week in the online early edition of the Proceedings of the National Academy of Sciences, James Poterba of MIT, Steven Venti of Dartmouth College and David Wise of Harvard University looked at how changes in types of pension plans and in demographic structure will affect the wealth of future retirees.

They found that if the average return on stocks for the next 35 years is three percentage points below its historical value, then the average value of 401(k) plan balances would increase from $29,700 in 2000 to $269,000 by 2040. If equity returns continue at their historical level, the average plan balance in 2040 would be even greater: $452,000 by 2040. All dollar values are measured in constant 2000 prices. The findings challenge some bearish projections that retirement assets will drop in value in coming decades as baby-boomers cash out their holdings. The team accounted for the discrepancy by noting that their research takes into effect the continuation of pension plan shifts away from traditional defined benefit plans toward 401(k) plans--a trend that has been under way for some 30 years.

In short, because most current retirees who have assets in 401(k) plans were covered by these plans for only a fraction of their working careers, the balances at retirement for future retirees are likely to be substantially greater than those of current retirees.

This is true even if the trend toward a growing fraction of the workforce covered by 401(k) plans slows or stops, said Poterba, head of MIT's economics department and the Mitsui Professor of Economics.

"The key touchstone here is that if in fact people are in these 401(k) retirement plans for three or four decades, they will have a lot more chance to build up their assets than the current crop of retirees--many of whom have only been investing in 401(k) plans for part of their careers," Poterba said.

The paper uses data on historical participation rates in, and contribution rates to, 401(k) plans to project the future evolution of 401(k) balances for retirement-aged households.

Poterba noted several important caveats to the research, chief of which was the difficulty of trying to make accurate projections of what will happen more than three decades from now.

He also said certain demographic groups may cash out their 401(k) plans prior to retirement, meaning they will not benefit from the projected large increase in their nest eggs.

The work was funded by the Social Security Administration, the National Institute of Aging and the National Science Foundation

Technorati : :
Ice Rocket :
Flickr :
Zooomr :
Buzznet :

The science of sexual arousal


Psychologists are gaining new insights into sexual arousal with the help of innovative research methods.

Men and women experience sexual arousal very differently, not only physiologically but psychologically, according to researchers who are studying arousal using an array of new and refined methods.

Those methods are making it possible for researchers to understand the causes of real-world problems, such as sexual dysfunction and high-risk sexual behavior (see pages 54 and 58). But they are also giving researchers the means to explore basic questions about the nature of sexual arousal and how its different components--such as physiological arousal and subjective experience--are related to each other.

"It's easier to get funding for research that focuses on, let's say, AIDS-related sexual behaviors, than for research on the very fundamental question of what sexual motivation and sexual arousal really are," says Erick Janssen, PhD, a psychologist at the Kinsey Institute for Research in Sex, Gender and Reproduction at Indiana University. "But in the long run, those basic questions have to be answered before we can move on to explain other, related behaviors."

Cognition and arousal

One active area of research concerns cognitive factors that influence sexual arousal. In the mid-1980s, Boston University psychologist David Barlow, PhD, and his colleagues conducted a series of studies to examine the relationship between anxiety and sexual arousal. They found that men with and without sexual problems reacted very differently to anxiety-inducing threats of mild electric shock.

Men who reported having no trouble getting and maintaining erections, says Barlow, "would believe that they were going to get shocked if they didn't get aroused, so they would focus on the erotic scene." The result was that the threat of shock actually increased sexual arousal. But men who had sexual problems responded to the threat of shock very differently, says Barlow. "Their attention would be so focused on the negative outcomes that they wouldn't be able to process the erotic cues," he explains.

Since those initial studies, Barlow and his collaborators have been trying to tease apart the factors that distinguish men with and without sexual problems. One of the key differences, he says, is that men with sexual arousal problems tend to be less aware of how aroused they are.

Another difference has to do with how men react to instances when they can't become aroused, says Barlow. "Males who are able to get aroused fairly easily seem unfazed by occasions where they can't get aroused," he notes. "They tend to attribute it to benign external events--it was something they ate, or they're not getting enough sleep--not as characteristics of themselves." In contrast, men with arousal problems tend to do just the opposite, thinking of every instance of difficulty as a sign of a long-term internal problem, either physiological or psychological, he says.

At the Kinsey Institute, Janssen and John Bancroft, MD, the institute's director, have been developing a theoretical model and a set of measurement tools that define sexual arousal as the product of excitatory and inhibitory tendencies. Last year, they published papers in the Journal of Sex Research (Vol. 39, No. 2) describing the Sexual Inhibition and Sexual Excitation Scale--a new questionnaire that measures individual differences in the tendency to become sexually inhibited and excited.

Early research on the model suggests that while a single factor accounts for all of the variation among men in their tendency to become sexually excited (SES), there are two inhibitory factors--one that represents inhibition due to the threat of performance failure (SIS1) and one that represents inhibition due to the threat of such performance consequences as an unwanted pregnancy or a sexually transmitted disease (SIS2).

One implication is that people with different levels of SES, SIS1 and SIS2 will respond differently to different kinds of stimuli, says Janssen. In one study, for instance, Janssen, Bancroft and their collaborators found that people who scored highly on SIS2 were less likely to be aroused by erotic films that included threatening stimuli than people with low SIS2 scores.

"We believe that people who are high in inhibition-proneness are more vulnerable to developing sexual problems, whereas those who are low are more likely to engage in high-risk sexual behavior," says Janssen.

Physiological and subjective arousal

For most of the history of research on sexual arousal, studies involving women have been much rarer than studies involving men. Recently, however, the gap has started to narrow due to the work of psychologists such as Cindy Meston, PhD, of the University of Texas at Austin, Julia Heiman, PhD, of the University of Washington, and Ellen Laan, PhD, of the University of Amsterdam. Janssen and his colleagues at the Kinsey Institute have also begun studying female arousal.

One of the most interesting results to come out of that work, researchers say, is that there are significant differences between men and women in the relationship between physiological and subjective arousal.

"What we find in research in males is there's a very high correlation between their erectile response and how aroused they say they are," says Meston. "But in women we get low, if any correlations."

In addition to being interesting from a scientific standpoint, the sex difference could also have important implications for the treatment of female sexual dysfunction, says Meston. Researchers have not yet been able to pinpoint the source of the difference, she says, but some progress has been made.

Several explanations that once seemed likely candidates have been eliminated in recent years. One of them is the idea that women are less likely than men to talk honestly about their sexuality because of sexual taboos. But Meston says she sees no evidence of reticence in the women who volunteer for her studies.

Another possibility is that erotic films might evoke negative emotions in women, which could mask their arousal. But Laan and her collaborators at the University of Amsterdam have found no evidence that such reactions can account for the physiology-experience gap.

Meston and others suspect that the difference probably has something to do with the fact that male genital arousal is simply easier to notice than female genital arousal. Men also seem to be more attentive than women to all kinds of physiological signals, not just sexual ones, says Janssen.

An open question is whether the resulting sex differences in the relationship between physiological and subjective arousal are permanent, or whether they can be changed through training. Meston says her lab is currently conducting a study to find that out.

Technorati : :
Ice Rocket :
Flickr :
Zooomr :
Buzznet :



In the Image

Steven P. Jobs, with his wife, Laurene Powell, is the subject of a blog that parodies his job as the chief executive of Apple.

For the last 14 months, high-tech insiders have been eating up the work of an anonymous blogger who assumed the persona of Steven P. Jobs, Apple's chief executive and one of the world's most famous businessmen.
The mysterious writer has used his blog, the Secret Diary of Steve Jobs, to lampoon Mr. Jobs and his reputation as a difficult and egotistical leader, as well as to skewer other high-tech companies, tech journalists, venture capitalists, open-source software fanatics and Silicon Valley's overall aura of excess.

The acerbic postings of "Fake Steve," as he is known, have attracted a plugged-in readership - both the real Mr. Jobs and Bill Gates have acknowledged reading the blog ( At the same time, Fake Steve has evaded the best efforts of Silicon Valley's gossips to discover his real identity.

Meanwhile, on the other side of the country, Daniel Lyons, a senior editor at Forbes magazine who lives near Boston, has been quietly enjoying the attention.

"I'm stunned that it's taken this long," said Mr. Lyons, 46, when a reporter interrupted his vacation in Maine on Sunday to ask him about Fake Steve. "I have not been that good at keeping it a secret. I've been sort of waiting for this call for months."

Mr. Lyons writes and edits technology articles for Forbes and is the author of two works of fiction, most recently a 1998 novel, "Dog Days." In October, Da Capo Press will publish his satirical novel written in the voice of the Fake Steve character, "Options: The Secret Life of Steve Jobs, a Parody."

Unlike the off-the-cuff ramblings on his blog, "Options" is a well-plotted satire that imagines Apple's chief executive grappling with his real-life stock option backdating troubles and getting help, and bad advice, from friends like Larry Ellison, Bono and Al Gore.

The book, in part, led to Mr. Lyons's unmasking. Last year, his agent showed the manuscript to several book publishers and told them the anonymous author was a published novelist and writer for a major business magazine. The New York Times found Mr. Lyons by looking for writers who fit those two criteria, and then by comparing the writing of "Fake Steve" to a blog Mr. Lyons writes in his own name, called Floating Point (

Mr. Lyons said he invented the Fake Steve character last year, when a small group of chief executives turned bloggers attracted some media attention. He noticed that they rarely spoke candidly. "I thought, wouldn't it be funny if a C.E.O. kept a blog that really told you what he thought? That was the gist of it."

Mr. Lyons says he recalled trying out the voices of several chief executives before settling on the colorful Apple co-founder. He twice tried to relinquish the blog, but started again after being deluged by fans e-mailing to ask why Fake Steve had disappeared.

Though manyspeculators have guessed Fake Steve was an Apple insider, Mr. Lyons says he has never interviewed Mr. Jobs nor written a story about the company. "I have zero sources inside Apple," he said. "I had to go out and get books and biographies to learn about a lot of the back story."

Mr. Lyons said writing as Fake Steve became addictive. He developed a unique lexicon and catalog of insults for the character. Bill Gates is Beastmaster, and Eric E. Schmidt, Google's chief executive, is Squirrel Boy.

Last month, when a reader asked Fake Steve about Apple's succession plan, he replied: "My plan at this time is to live forever and to remain in charge here, though perhaps with fewer restrictions on my power. The truth is, I am not human - I am a man-god, son of Zeus, born to mortal woman but fathered by the ruler of the gods, lord of thunder."

Mr. Lyons receives around 50 e-mail messages a day through the blog, many with ideas for posts, and says the site had 700,000 visitors last month. Recently someone claiming to be Mr. Jobs's daughter, Lisa, wrote to tell him, "You don't sound at all like my father, but your blog is hilarious."

The guessing game around his identity was intense, with speculation centering on a variety of plugged-in journalists, former Apple employees and even Mr. Jobs himself.

Over the last year, Forbes's publisher, Richard Karlgaard, even got into the act, speculating about Fake Steve's identity on several times. At one point he wrote: "The guessing game has begun. Who is writing it? Send me your guesses. I'll gladly buy the most expensive iPod for the first to identify Fake Steve Jobs."

Mr. Lyons said he felt bad and later revealed himself to his bosses and colleagues.

Mr. Karlgaard said he had a good laugh and holds no grudges. "I think it is the most brilliant caricature of an important part of American culture that I've seen," he said. "We're really proud that he's one of ours."

Forbes had planned to move the Secret Diary to in September, although it may now accelerate the move.

The Fake Steve saga calls to mind the guessing game behind "Primary Colors," the political roman à clef written in 1992 by Joe Klein, then a Newsweek writer. Newsweek reacted differently, however, firing Mr. Klein when he allowed other writers at the magazine to speculate on the book's author without tipping them off.

Mr. Lyons clearly used the Fake Steve persona to further some of his own interests and positions. For example, articles in other business publications and their journalists were a frequent target of criticism from Fake Steve, while Forbes got off comparatively easy.

Fake Steve also had it in for the devout fans of the open-source operating system Linux, calling them "freetards." Mr. Lyons has written several articles for Forbes in which he has been critical of the cultlike aura around the free software movement and its founder, Richard Stallman.

He said that he never intended his blog to be mean-spirited and that he is a fan and customer of Apple. "If I really thought the Apple guys were going to find this guy and kill him, I wouldn't want to do it. I was kind of hoping it would be puckish and fun. I think the guys in the Valley like the fact that it makes them into fictional characters. It's a comic strip."

Asked whether he was worried that he would be called to account for some of Fake Steve's stinging, personal posts, Mr. Lyons chuckled and said, "Yes."

As for Mr. Jobs himself - the real one - he did not seem all that interested when told the identity of his online doppelganger. He said in an instant message conversation that he had no interest in reading Mr. Lyons's novel.

Technorati :

Scond life comes reality in life

Second lifesecond lie 1

Coldwell Banker Puts Real House on Second Life Block

Second Life is a 3-D virtual world entirely built and owned by its Residents. Since opening to the public in 2003, it has grown explosively and today is inhabited by a total of 8,661,636 Residents from around the globe.

From the moment you enter the World you'll discover a vast digital continent, teeming with people, entertainment, experiences and opportunity. Once you've explored a bit, perhaps you'll find a perfect parcel of land to build your house or business.

You'll also be surrounded by the Creations of your fellow Residents. Because Residents retain the rights to their digital creations, they can buy, sell and trade with other Residents.

The Marketplace currently supports millions of US dollars in monthly transactions. This commerce is handled with the in-world unit-of-trade, the Linden dollar, which can be converted to US dollars at several thriving online Linden Dollar exchanges.

About Second life

Second Life is a 3-D virtual world entirely built and owned by its Residents. Since opening to the public in 2003, it has grown explosively and today is inhabited by a total of 8,661,636 Residents from around the globe.

  • From the moment you enter the World you'll discover a vast digital continent, teeming with people, entertainment, experiences and opportunity. Once you've explored a bit, perhaps you'll find a perfect parcel of land to build your house or business.

  • You'll also be surrounded by the Creations of your fellow Residents. Because Residents retain the rights to their digital creations, they can buy, sell and trade with other Residents.

  • The Marketplace currently supports millions of US dollars in monthly transactions. This commerce is handled with the in-world unit-of-trade, the Linden dollar, which can be converted to US dollars at several thriving online Linden Dollar exchanges.

Technorati :


We are readyImage above: The crew members of STS-118 pose for their official portrait. Pictured from the left are mission specialists Richard A. (Rick) Mastracchio, Barbara R. Morgan, Pilot Charles O. Hobaugh, Commander Scott J. Kelly and mission specialists Tracy E. Caldwell, Canadian Space Agency's Dafydd R. (Dave) Williams, and Alvin Drew Jr. Credit

Space Shuttle Endeavour's STS-118 mission is the 22nd shuttle flight to the International Space Station. It will continue space station construction by delivering a third starboard truss segment. + Visit the STS-118 Educators' Resource Page

U.S. Navy Commander Scott J. Kelly will command the seven-person crew of STS-118. U.S. Marine Corps Lt. Col Charles O. Hobaugh will be Endeavour's pilot. Veteran astronauts Richard A. Mastracchio and Dr. Dafydd (Dave) Williams of the Canadian Space Agency will be returning to space for their second missions. Barbara R. Morgan, Tracy E. Caldwell, Ph. D., and Benjamin Alvin Drew round out the crew as mission specialists.

Technorati : :
Ice Rocket :

Find here

Home II Large Hadron Cillider News