Portrait of Woman Revealed Beneath Van Gogh Painting

By LiveScience Staff

A previously unknown portrait of a woman by Vincent van Gogh has been revealed in a high-tech look beneath another of his paintings, it was announced today.

Scientists used a new technique to peer beneath the paint of van Gogh's "Patch of Grass." Already it was known there was something there, likely a portrait of some sort. Van Gogh was known to paint over his work, perhaps as much as a third of the time.

Behind the painting, done mostly in greens and blues, is a portrait of a woman rendered in browns and reds.

The new technique is based on "synchrotron radiation induced X-ray fluorescence spectroscopy" and is said to be an improvement on X-ray radiography, which has been used to reveal concealed layers of other famous paintings. The new method measures chemicals in the pigments. Specifically, mercury and the element antimony were useful in revealing the woman's face.

The work was done by researchers at Delft University of Technology in the the Netherlands and the University of Antwerp in Belgium, along with help from other institutions.

"Patch of Grass" was painted by van Gogh in Paris in 1887 and is owned by the Kröller-Müller Museum.

The reconstruction enables art historians to understand the evolution of van Gogh’s work better, the researchers said in a statement. And the new technique is expected to pave the way for research into many other concealed paintings.

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Top 5 Most Charitable U.S. Cities and States

Volunteers perform invaluable service to their communities.

Photo: Tanglewood 4-H Camp and Learning Center

Let it never be said that Americans aren't a generous or charitable people. In fact, the most comprehensive research on U.S. volunteering ever assembled has just been released, and the numbers are encouraging -- particularly given the soft economy and an uncertain global future.

Today the results of the Volunteering in America report were unveiled, based on six years of data, by the Corporation for National and Community Service and the USA Freedom Corps. The data show that nearly 61 million Americans volunteered in their communities in 2007, giving 8.1 billion hours of service worth more than $158 billion. As the report authors point out, many factors have made it easier for ordinary folk to give of themselves, from broad adoption by companies of social and environmental responsibility initiatives to support from local governments, faith-based and community service groups and much more.

Nationally, 60.8 million or 26.2 percent of Americans age 16 and older volunteered through organizations in 2007. After a 6% dip in volunteers between 2005 and 2006, volunteering levels stabilized in 2007. Notably, the study reported that today's young people are volunteering at higher rates than the last generation (perhaps those Gen Xers really were too jaded), while Baby Boomers are expected to move into their Golden Years with a strong commitment to community service.

Volunteer time spent was pretty evenly distributed among fundraising, collecting and distributing food, general labor and tutoring/teaching. The religious, educational and social services sectors saw the biggest contributions. It is currently unclear if data has been specifically tabulated on volunteering on behalf of the environment, though such efforts are clearly covered in the overall numbers.

In addition to analyzing data across the country, the report looked at how volunteers and non-volunteers spend time. The largest difference was, perhaps not surprisingly, in how much time people spend watching TV. In a typical week, volunteers spend 15 hours with the boob tube, compared to 23 hours for non-volunteers. That difference adds up to more than 400 hours in a year. Volunteers were also more likely to spend more of their day interacting with others.

Women were more likely to volunteer than men (30.6% versus 23.6%). College towns had a particularly high rate of service, and the region with the highest percentage was the Midwest.

Most Generous States, By Volunteer Hours

1. Utah, 43.9%
2. Nebraska, 39.8%
3. Minnesota, 39.7%
4. Alaska 38.6%
5. Montana 38.0%

Most Generous Mid-Size Cities, By Volunteer Hours

1. Provo, Utah 63.8%
2. Iowa City, Iowa 45.1%
3. Madison, Wis., 42.3%
4. Greenville, S.C. 41.0%
5. Ogden, Utah 41.0%

Most Generous Large Cities, By Volunteer Hours

1. Minneapolis-St. Paul, 39.3%
2.Salt Lake City, 37.2%
3. Portland, Oregon 35.6%
4. Seattle, 35.5%
5. Austin, 35.3%

(National average: 27.2%)

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Aging impairs the 'replay' of memories during sleep

Aging impairs the consolidation of memories during sleep, a process important in converting new memories into long-term ones, according to new animal research in the July 30 issue of The Journal of Neuroscience. The findings shed light on normal memory mechanisms and how they are disrupted by aging.

During sleep, the hippocampus, a brain region important in learning and memory, repeatedly "replays" brain activity from recent awake experiences. This replay process is believed to be important for memory consolidation. In the new study, Carol Barnes, PhD, and colleagues at the University of Arizona found reduced replay activity during sleep in old compared to young rats, and rats with the least replay activity performed the worst in tests of spatial memory.

Barnes and colleagues recorded hippocampal activity in 11 young and 11 old rats as they navigated several mazes for food rewards. Later, when the animals were asleep, the researchers recorded their hippocampal activity again. In the young animals, the sequence of neural activity recorded while the animals navigated the mazes was repeated when they slept. However, in most of the old animals, the sequence of neural activity recorded during sleep did not reflect the sequence of brain activity recorded in the maze.

"These findings suggest that some of the memory impairment experienced during aging could involve a reduction in the automatic process of experience replay," said Michael Hasselmo, DPhil, at Boston University, an expert unaffiliated with the study.

Animals with more faithful sleep replay also performed better on memory tests. The researchers tested the same 22 rats on a spatial learning and memory task. Consistent with previous research, the young rats recalled the solution to the spatial task faster and more accurately than the old rats. In the old group, the researchers found that the top performers in the spatial memory task were also the ones that showed the best sleep replay. Irrespective of the animal's age, the researchers found that animals who more faithfully replayed the sequence of neural activity recorded in the maze while asleep also performed better on the spatial memory task.

"This is the first study to suggest that an animal's ability to perform a spatial memory task may be related to the brain's ability to perform memory consolidation during sleep," said study author Barnes.

Identification of the specific memory deficit present in the aging brain may be a first step to preventing age-related memory loss. "This study's findings could inspire the development and testing of pharmacological agents designed to enhance memory replay phenomena," Hasselmo said.

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