30 December 2011Last updated at 07:50 ETBy Mark KinverEnvironment reporter, BBC News
A model has helped shed light on how human-started fires shaped Africa's landscape, researchers report.
Before human activity became widespread, most fires were caused by lightning strikes during the continent's wet seasons, they said.
As the human population expanded, more fires occurred during the dry season, triggering a shift in the impact of fires on Africa's ecology, they added.
The findings appear in the Proceedings of the National Academy of Sciences.
"People have always been aware that there have been a lot of wildfires in Africa," said co-author Sally Archibald, senior researcher at the Council for Scientific and Industrial Research, South Africa.
"When we started getting satellite data, it became even more apparent that there is a lot of burning that happens.
"This made people concerned; they were worried that there was too much fire in Africa."
Human impact
Dr Archibald explained that the team decided to develop the model in order to understand current conditions, and whether there was now too much burning compared with the time when humans were not so prevalent and influencing landscapes' "fire regimes".
It has been estimated that early humans could have had the ability to start fires about 300,000 years ago, but the real impact was from about 70,000 years ago as human populations became more widespread.
"We really cannot make good (conservation) decisions unless we can understand how humans have manipulated fire," added Dr Archibald.
"It is really interesting that we are the only organism in the world to have harnessed fire, and we need to understand how that may have changed the systems in which we live."
The theoretical model, which focuses on Africa's grassland habitats, took data on how people have used fire and linked it to archaeological knowledge of how human populations in the region evolved.
Dr Archibald told BBC News that one of the paper's key insights was that, according to the model, wildfires were currently at their "lowest level for the past 40,000 years or so".
"There is less wildfire in Africa now, even though it looks like there is such a lot when you look at the satellite data, because of the way that people have been using the landscape."
She explained that the model could be used to help national parks develop fire management policies.
"They are trying to develop fire management policies and they want to burn their landscapes in a way that will maintain biodiversity," she said.
"That becomes quite a tricky question in Africa because you cannot just say 'well, I will not light fires at all, only natural fires will be allowed'.
"People have been in Africa for over a million years, so you cannot try to suppress all human fires. You have to include humans as part of your system, and fire managers still need some guidance on what is the best way to burn these systems and yet maintain biodiversity."
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Today was rubbish. 14 hour accounting marathon. Goodness. Tomoro should be better going to Rome to do radio interviews and to say ciaoIl y a environ 19 heuresvia Twitter for iPhone from Pienza, Sienne??
Diet patterns may keep brain from shrinkingPublic release date: 28-Dec-2011 [ | E-mail | Share ]
Contact: Rachel Seroka rseroka@aan.com 651-695-2738 American Academy of Neurology
ST. PAUL, Minn. People with diets high in several vitamins or in omega 3 fatty acids are less likely to have the brain shrinkage associated with Alzheimer's disease than people whose diets are not high in those nutrients, according to a new study published in the December 28, 2011, online issue of Neurology, the medical journal of the American Academy of Neurology.
Those with diets high in omega 3 fatty acids and in vitamins C, D, E and the B vitamins also had higher scores on mental thinking tests than people with diets low in those nutrients. These omega 3 fatty acids and vitamin D are primarily found in fish. The B vitamins and antioxidants C and E are primarily found in fruits and vegetables.
In another finding, the study showed that people with diets high in trans fats were more likely to have brain shrinkage and lower scores on the thinking and memory tests than people with diets low in trans fats. Trans fats are primarily found in packaged, fast, fried and frozen food, baked goods and margarine spreads.
The study involved 104 people with an average age of 87 and very few risk factors for memory and thinking problems. Blood tests were used to determine the levels of various nutrients present in the blood of each participant. All of the participants also took tests of their memory and thinking skills. A total of 42 of the participants had MRI scans to measure their brain volume.
Overall, the participants had good nutritional status, but seven percent were deficient in vitamin B12 and 25 percent were deficient in vitamin D.
Study author Gene Bowman, ND, MPH, of Oregon Health & Science University in Portland and a member of the American Academy of Neurology, said that the nutrient biomarkers in the blood accounted for a significant amount of the variation in both brain volume and thinking and memory scores. For the thinking and memory scores, the nutrient biomarkers accounted for 17 percent of the variation in the scores. Other factors such as age, number of years of education and high blood pressure accounted for 46 percent of the variation. For brain volume, the nutrient biomarkers accounted for 37 percent of the variation.
"These results need to be confirmed, but obviously it is very exciting to think that people could potentially stop their brains from shrinking and keep them sharp by adjusting their diet," Bowman said.
The study was the first to use nutrient biomarkers in the blood to analyze the effect of diet on memory and thinking skills and brain volume. Previous studies have looked at only one or a few nutrients at a time or have used questionnaires to assess people's diet. But questionnaires rely on people's memory of their diet, and they also do not account for how much of the nutrients are absorbed by the body, which can be an issue in the elderly.
###
The study was supported by the National Institutes of Health, the National Institute on Aging and National Center for Complementary and Alternative Medicine and the U.S. Department of Veteran Affairs, Portland VA Medical Center.
The American Academy of Neurology, an association of 24,000 neurologists and neuroscience professionals, is dedicated to promoting the highest quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer's disease, stroke, migraine, multiple sclerosis, brain injury, Parkinson's disease and epilepsy.
For more information about the American Academy of Neurology, visit http://www.aan.com or find us on Facebook, Twitter, Google+ and YouTube.
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AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Diet patterns may keep brain from shrinkingPublic release date: 28-Dec-2011 [ | E-mail | Share ]
Contact: Rachel Seroka rseroka@aan.com 651-695-2738 American Academy of Neurology
ST. PAUL, Minn. People with diets high in several vitamins or in omega 3 fatty acids are less likely to have the brain shrinkage associated with Alzheimer's disease than people whose diets are not high in those nutrients, according to a new study published in the December 28, 2011, online issue of Neurology, the medical journal of the American Academy of Neurology.
Those with diets high in omega 3 fatty acids and in vitamins C, D, E and the B vitamins also had higher scores on mental thinking tests than people with diets low in those nutrients. These omega 3 fatty acids and vitamin D are primarily found in fish. The B vitamins and antioxidants C and E are primarily found in fruits and vegetables.
In another finding, the study showed that people with diets high in trans fats were more likely to have brain shrinkage and lower scores on the thinking and memory tests than people with diets low in trans fats. Trans fats are primarily found in packaged, fast, fried and frozen food, baked goods and margarine spreads.
The study involved 104 people with an average age of 87 and very few risk factors for memory and thinking problems. Blood tests were used to determine the levels of various nutrients present in the blood of each participant. All of the participants also took tests of their memory and thinking skills. A total of 42 of the participants had MRI scans to measure their brain volume.
Overall, the participants had good nutritional status, but seven percent were deficient in vitamin B12 and 25 percent were deficient in vitamin D.
Study author Gene Bowman, ND, MPH, of Oregon Health & Science University in Portland and a member of the American Academy of Neurology, said that the nutrient biomarkers in the blood accounted for a significant amount of the variation in both brain volume and thinking and memory scores. For the thinking and memory scores, the nutrient biomarkers accounted for 17 percent of the variation in the scores. Other factors such as age, number of years of education and high blood pressure accounted for 46 percent of the variation. For brain volume, the nutrient biomarkers accounted for 37 percent of the variation.
"These results need to be confirmed, but obviously it is very exciting to think that people could potentially stop their brains from shrinking and keep them sharp by adjusting their diet," Bowman said.
The study was the first to use nutrient biomarkers in the blood to analyze the effect of diet on memory and thinking skills and brain volume. Previous studies have looked at only one or a few nutrients at a time or have used questionnaires to assess people's diet. But questionnaires rely on people's memory of their diet, and they also do not account for how much of the nutrients are absorbed by the body, which can be an issue in the elderly.
###
The study was supported by the National Institutes of Health, the National Institute on Aging and National Center for Complementary and Alternative Medicine and the U.S. Department of Veteran Affairs, Portland VA Medical Center.
The American Academy of Neurology, an association of 24,000 neurologists and neuroscience professionals, is dedicated to promoting the highest quality patient-centered neurologic care. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer's disease, stroke, migraine, multiple sclerosis, brain injury, Parkinson's disease and epilepsy.
For more information about the American Academy of Neurology, visit http://www.aan.com or find us on Facebook, Twitter, Google+ and YouTube.
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Toasting the chemistry of champagne: New Year's Eve video from the American Chemical SocietyPublic release date: 27-Dec-2011 [ | E-mail | Share ]
Contact: Michael Bernstein m_bernstein@acs.org 202-872-6042 American Chemical Society
WASHINGTON, Dec. 27, 2011 Just in time for those New Year's Eve toasts, which might include a farewell to the International Year of Chemistry, the world's largest scientific society today posted online a video on the chemistry of champagne. The latest addition to the award-winning Bytesize Science series from the American Chemical Society (ACS) is available at www.BytesizeScience.com.
It explains that champagne, unlike other wines, undergoes a second fermentation in the bottle to trap carbon dioxide gas, which dissolves into the wine and forms the fabled bubbles in the bubbly. More than 600 different chemical compounds join carbon dioxide in champagne, each lending its own unique quality to the aroma and flavor of champagne.
But even with all of that flavor, champagne would be just another white wine without those tiny bubbles. As the bubbles ascend the length of a glass in tiny trains, they drag along molecules of those 600 flavor and aroma substances. They literally explode out of the surface as the bubbles burst, tickling the nose and stimulating the senses.
Some accounts say that a French Benedictine monk named Dom Pierre Prignon discovered champagne in the mid-1600s, and became namesake for the famous champagne cuve, Dom Prignon. The video points out that early champagne makers had a tough time with that second fermentation. Some bottles wound up with no bubbles at all. Others got too much carbon dioxide, and exploded under the enormous pressure, wasting the precious vintage.
So what's the best way to pour a glass of bubbly and maximize the sensory experience?
For an answer, the video turns to a study published in the Journal of Agricultural and Food Chemistry, one of more than 40 peer-reviewed scientific journals published by the ACS. Pouring champagne on an angle retains up to twice as much carbon dioxide in the champagne when compared to pouring down the middle of the glass. Those additional bubbles carry out more of the hundreds of flavor compounds in champagne.
###
Viewed thousands of times each month, the newly re-launched Bytesize Science series uncovers the chemistry in everyday life. Subscribe to Bytesize Science on YouTube for new videos featuring hands-on demos of scientific phenomena, cutting-edge research found in ACS' 43 peer-reviewed journals and Chemical & Engineering News, interviews with scientific leaders and episodes highlighting the chemistry behind popular foods, products and discoveries that improve people's lives around the world.
For more entertaining, informative science videos and podcasts from the ACS Office of Public Affairs, view Prized Science, Spellbound, Science Elements, and Global Challenges/Chemistry Solutions.
The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 163,000 members, ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.
To automatically receive news releases from the American Chemical Society contact newsroom@acs.org.
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AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
Toasting the chemistry of champagne: New Year's Eve video from the American Chemical SocietyPublic release date: 27-Dec-2011 [ | E-mail | Share ]
Contact: Michael Bernstein m_bernstein@acs.org 202-872-6042 American Chemical Society
WASHINGTON, Dec. 27, 2011 Just in time for those New Year's Eve toasts, which might include a farewell to the International Year of Chemistry, the world's largest scientific society today posted online a video on the chemistry of champagne. The latest addition to the award-winning Bytesize Science series from the American Chemical Society (ACS) is available at www.BytesizeScience.com.
It explains that champagne, unlike other wines, undergoes a second fermentation in the bottle to trap carbon dioxide gas, which dissolves into the wine and forms the fabled bubbles in the bubbly. More than 600 different chemical compounds join carbon dioxide in champagne, each lending its own unique quality to the aroma and flavor of champagne.
But even with all of that flavor, champagne would be just another white wine without those tiny bubbles. As the bubbles ascend the length of a glass in tiny trains, they drag along molecules of those 600 flavor and aroma substances. They literally explode out of the surface as the bubbles burst, tickling the nose and stimulating the senses.
Some accounts say that a French Benedictine monk named Dom Pierre Prignon discovered champagne in the mid-1600s, and became namesake for the famous champagne cuve, Dom Prignon. The video points out that early champagne makers had a tough time with that second fermentation. Some bottles wound up with no bubbles at all. Others got too much carbon dioxide, and exploded under the enormous pressure, wasting the precious vintage.
So what's the best way to pour a glass of bubbly and maximize the sensory experience?
For an answer, the video turns to a study published in the Journal of Agricultural and Food Chemistry, one of more than 40 peer-reviewed scientific journals published by the ACS. Pouring champagne on an angle retains up to twice as much carbon dioxide in the champagne when compared to pouring down the middle of the glass. Those additional bubbles carry out more of the hundreds of flavor compounds in champagne.
###
Viewed thousands of times each month, the newly re-launched Bytesize Science series uncovers the chemistry in everyday life. Subscribe to Bytesize Science on YouTube for new videos featuring hands-on demos of scientific phenomena, cutting-edge research found in ACS' 43 peer-reviewed journals and Chemical & Engineering News, interviews with scientific leaders and episodes highlighting the chemistry behind popular foods, products and discoveries that improve people's lives around the world.
For more entertaining, informative science videos and podcasts from the ACS Office of Public Affairs, view Prized Science, Spellbound, Science Elements, and Global Challenges/Chemistry Solutions.
The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. With more than 163,000 members, ACS is the world's largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.
To automatically receive news releases from the American Chemical Society contact newsroom@acs.org.
[ | E-mail | Share ]
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AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
[unable to retrieve full-text content]A future gaming world of 100% digital games? Pravkebab: I love collecting games and not just playing them and I think that one day we will see a world of pure digital content. (Industry, PS3, Wii, Wii U, Xbox 360). Read full story >> Comments ...
The Portland Tribune, Dec 21, 2011, Updated 12.2 hours ago
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The City Council approved a one-year pilot program to allow a limited amount of camping at churches and nonprofit organizations on Wednesday morning.
The resolution authorizing the program was introduced by Housing Commissioner Nick Fish, who said it supplements other efforts by the city and Multnomah County to end homeless. The Multnomah County Commission is expected to approve a similar program Thursday, and to also approve spending $750,000 to help find permanent housing for those who take advantage of it.
The program approved by the council will allow camping in up to four motor vehicles owned or operated by churches and non-profit agencies in the cities that participate in it. They must provide access to water and restroom facilities.
Fish wrote the resolution with a number of religious and non-profit organizations, including Ecumenical Ministries of Oregon. It was inspired in part by the ongoing homeless camp at Northwest Third Avenue and Burnside Street known as Right 2 Dream Too. The program does not include the camp, however.
Dozens of homeless people and their supporters testified by the council vote. Many called the program inadequate considering the number of people needing housing in Portland, and Fish agreed.
"This resolution does not solve the problem," Fish said. "But when people of good faith come to us and ask us to do something, I think we should agree. It is not intended to solve the problem or be comprehensive in scope."
The city has policies that prohibit public camping. It is defending the legality of those policies in federal court. The Oregon Law Center has filed a lawsuit against the city, saying the policies are unconstitutional.
Defending Portland's efforts to end homelessness, Fish noted the city is sending millions of dollars a year on housing program. It recently funded Bud Clark Commons, formerly called the Regional Access Center, which provides apartments to some of the city's most vulnerable homeless people.
The resolution passed with the support of Commissioners Fish, Randy Leonard and Dan Saltzman. Mayor Sam Adams and Commissioner Amanda Fritz were absent.
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Public release date: 28-Dec-2011
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