Sensing Wind Speed with Kites
Kites have a storied history in meteorological research -- think of Benjamin Franklin and his study of electricity -- including being used to carry aloft sensors that measure wind speed. Previously, however, these sensors, because they were exposed to direct sunlight, were prone to temperature errors that affected their accuracy. Now researchers at the University of Reading in the United Kingdom have developed a way to use a kite itself to measure wind speed.
The researchers, professor of atmospheric physics Giles Harrison and applied meteorologist Kieran Walesby, describe their device in the AIP's Review of Scientific Instruments. The instrument consists of a 2-meter-long and 1-meter-wide Rokkaku-type kite -- a simple-to-construct Japanese kite design with "good stability, reasonable load-carrying capacity, and a low sink rate when the wind speed drops," Harrison says -- attached to a ground-based strain gauge that monitors the tension in the kite's tether line. That line tension, Harrison and Walesby found, is linearly related to wind speed.
"The kite method is portable and cheap, and removes the need for a mast to support an anemometer," Harrison says. "A particular use is to provide measurements above those reached by masts" -- although, he adds, "it will work less well at low levels, or in very turbulent conditions. We expect to refine the kite design to allow operation in a wider range of conditions, and to encourage wider adoption of our approach."
The article, "A thermally stable tension meter for atmospheric soundings using kites" by K. T. Walesbya and R. G. Harrison was published online in the journal Review of Scientific Instruments on July 21, 2010. See: http://rsi.aip.org/rsinak/v81/i7/p076104_s1
Thursday, July 29, 2010
Wednesday, June 30, 2010
More Oil Spills to Come, Says Anthropologist
The Deepwater Horizon oil spill in the Gulf of Mexico is not simply a random accident. There will be more of these spills to come, as the days of easy oil are over, says an anthropologist at Washington University in St. Louis.
“BP and other oil companies have tried to portray this spill as an accident or an aberration, but in fact there are spills on off-shore and on-shore sites around the world, increasingly,” says Bret Gustafson, PhD, associate professor of anthropology in Arts & Sciences. Gustafson teaches a course on “Oil Wars: America and the Cultural Politics of Global Energy.”
A rig sank off the coast of Venezuela in May. Last October, a rig spilled oil for two months into the Timor Sea off of Australia. There are recurring spills in virtually every oil region, such as the Peruvian and Ecuadorian Amazon and Nigeria.
“These environmental and public health catastrophes are almost always accompanied by corruption and violence tied to oil activities,” Gustafson says. In the United States, which is more of a consumer than producer of oil, we are generally ignorant about this reality of oil until something like this comes home to roost.”
“Oil has always been destructive, but it is worsening because the days of easy oil are over,” says Gustafson, who currently is studying Bolivia's natural gas boom and the cultural politics of energy resources in Bolivia and neighboring Brazil, which consumes most of Bolivia's gas.
“In combination with weak regulation and intensifying competition, which explains why companies are willing to cut so many corners, oil is in more difficult places, both environmentally, politically and socially,” Gustafson says. “The point is that it is only going to get worse, and that the message by some commentators and the oil companies that we should just get on with business as usual is, quite frankly, almost criminal.”
Gustafson suggests that along with policies to transition us beyond oil and changes in our culture of consumption, we might also debate whether state control of oil companies, popular in other nations around the world, could work in the United States.
At least that way, Gustafson suggests, benefits would accrue to America’s public needs, rather than to multinational firms like BP. “Right now, the American people are subsidizing Big Oil, not benefitting from it,” he says.
“The press and public are only now debating the benefits or costs of regulation, but in fact the United States is the odd-man out in the world, where regulation goes along with government ownership and control,” Gustafson says. “Nearly all oil-producing countries, and not just third world ones, have government run oil companies, called National Oil Companies (NOCs). In places like Norway and Brazil, these contribute greatly to social benefits. Even the World Bank sees NOCs as a potential contributor to economic development. This is not a radical idea.”
Gustafson finds it curious that “our own culture of oil has largely silenced debate on whether or not having a national oil company would address both the environmental and regulatory concerns, as well as some of our other economic needs. Ideally, public and environmental concerns, rather than profit, would be the motivating logic behind oil operations.”
“The cultural addiction we have to oil contributes to both our relative ignorance about its negative effects and our relative willingness to accept these negative effects when they happen,” Gustafson says. “Despite the fact that most of us distrust big oil companies — we vilify them in our movies, our literature and our daily conversations — we are also generally complacent about what they do. When something like oil is so pervasive, it easily becomes invisible or at least very durable and resistant to cultural reflection and change.”
The one benefit of the spill, despite its catastrophic effects, may be, says Gustafson, that more of these issues are being brought into public discussion.
The Deepwater Horizon oil spill in the Gulf of Mexico is not simply a random accident. There will be more of these spills to come, as the days of easy oil are over, says an anthropologist at Washington University in St. Louis.
“BP and other oil companies have tried to portray this spill as an accident or an aberration, but in fact there are spills on off-shore and on-shore sites around the world, increasingly,” says Bret Gustafson, PhD, associate professor of anthropology in Arts & Sciences. Gustafson teaches a course on “Oil Wars: America and the Cultural Politics of Global Energy.”
A rig sank off the coast of Venezuela in May. Last October, a rig spilled oil for two months into the Timor Sea off of Australia. There are recurring spills in virtually every oil region, such as the Peruvian and Ecuadorian Amazon and Nigeria.
“These environmental and public health catastrophes are almost always accompanied by corruption and violence tied to oil activities,” Gustafson says. In the United States, which is more of a consumer than producer of oil, we are generally ignorant about this reality of oil until something like this comes home to roost.”
“Oil has always been destructive, but it is worsening because the days of easy oil are over,” says Gustafson, who currently is studying Bolivia's natural gas boom and the cultural politics of energy resources in Bolivia and neighboring Brazil, which consumes most of Bolivia's gas.
“In combination with weak regulation and intensifying competition, which explains why companies are willing to cut so many corners, oil is in more difficult places, both environmentally, politically and socially,” Gustafson says. “The point is that it is only going to get worse, and that the message by some commentators and the oil companies that we should just get on with business as usual is, quite frankly, almost criminal.”
Gustafson suggests that along with policies to transition us beyond oil and changes in our culture of consumption, we might also debate whether state control of oil companies, popular in other nations around the world, could work in the United States.
At least that way, Gustafson suggests, benefits would accrue to America’s public needs, rather than to multinational firms like BP. “Right now, the American people are subsidizing Big Oil, not benefitting from it,” he says.
“The press and public are only now debating the benefits or costs of regulation, but in fact the United States is the odd-man out in the world, where regulation goes along with government ownership and control,” Gustafson says. “Nearly all oil-producing countries, and not just third world ones, have government run oil companies, called National Oil Companies (NOCs). In places like Norway and Brazil, these contribute greatly to social benefits. Even the World Bank sees NOCs as a potential contributor to economic development. This is not a radical idea.”
Gustafson finds it curious that “our own culture of oil has largely silenced debate on whether or not having a national oil company would address both the environmental and regulatory concerns, as well as some of our other economic needs. Ideally, public and environmental concerns, rather than profit, would be the motivating logic behind oil operations.”
“The cultural addiction we have to oil contributes to both our relative ignorance about its negative effects and our relative willingness to accept these negative effects when they happen,” Gustafson says. “Despite the fact that most of us distrust big oil companies — we vilify them in our movies, our literature and our daily conversations — we are also generally complacent about what they do. When something like oil is so pervasive, it easily becomes invisible or at least very durable and resistant to cultural reflection and change.”
The one benefit of the spill, despite its catastrophic effects, may be, says Gustafson, that more of these issues are being brought into public discussion.
Wednesday, March 10, 2010
Study Provides a Better Understanding of How Mosquitoes Find a Host
The potentially deadly yellow-fever-transmitting Aedes aegypti mosquito detects the specific chemical structure of a compound called octenol as one way to find a mammalian host for a blood meal, Agricultural Research Service (ARS) scientists report.
Scientists have long known that mosquitoes can detect octenol, but this most recent finding by ARS entomologists Joseph Dickens and Jonathan Bohbot explains in greater detail how Ae. aegypti--and possibly other mosquito species--accomplish this.
Dickens and Bohbot, at the ARS Invasive Insect Biocontrol and Behavior Laboratory in Beltsville, Md., have shown that Ae. aegypti taps into the "right-handed" and "left-handed" structural nature of octenol, which is emitted by people, cattle and other mammals. This ability to detect the "handedness" of molecules has been shown in mammals, but the discovery is the first case of scientists finding out how it works in an insect, according to the researchers.
When they hunt for a blood meal, mosquitoes hone in on a variety of chemicals, including carbon dioxide, lactic acid, ammonia and octenol. Octenol is one of many carbon-based compounds that have a molecular structure that can take on either a "right-handed" or "left-handed" form. Each form is a mirror image of the other, and a form's "handedness" is determined by how its molecular bonds are assembled.
The scientists used frog eggs to help them make their discovery. They injected RNA from Ae. aegypti into the frog eggs, allowing the egg membranes to mimic the mosquito's ability to detect octenol. Then they attached microelectrodes to the frog egg cell membranes, passed octenol over them and recorded the electrical signals stimulated by the odors.
They ran the tests using both the right- and left-handed forms of octenol. The scientists found heightened electrical activity when the membrane was exposed to the right-handed form, and weakened activity when it was exposed to the left-handed form.
There are many natural compounds that can take on either a right-handed or left-handed form. While the effects of those differences on many plants and animals remains a mystery, the report, published in PLoS ONE, shows the effects of octenol's dual structure on the yellow fever mosquito and adds to scientists' understanding of how mosquitoes sense the world around them. It also may open the door to speedier development of better mosquito repellents and traps, according to Dickens.
The team's research is being funded by the Department of Defense Deployed War Fighter Protection Research Program.
ARS is the principal intramural scientific research agency of the U.S. Department of Agriculture.
USDA is an equal opportunity provider, employer and lender. To file a complaint of discrimination, write: USDA, Director, Office of Civil Rights, 1400 Independence Ave., S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice), or (202) 720-6382 (TDD).
The potentially deadly yellow-fever-transmitting Aedes aegypti mosquito detects the specific chemical structure of a compound called octenol as one way to find a mammalian host for a blood meal, Agricultural Research Service (ARS) scientists report.
Scientists have long known that mosquitoes can detect octenol, but this most recent finding by ARS entomologists Joseph Dickens and Jonathan Bohbot explains in greater detail how Ae. aegypti--and possibly other mosquito species--accomplish this.
Dickens and Bohbot, at the ARS Invasive Insect Biocontrol and Behavior Laboratory in Beltsville, Md., have shown that Ae. aegypti taps into the "right-handed" and "left-handed" structural nature of octenol, which is emitted by people, cattle and other mammals. This ability to detect the "handedness" of molecules has been shown in mammals, but the discovery is the first case of scientists finding out how it works in an insect, according to the researchers.
When they hunt for a blood meal, mosquitoes hone in on a variety of chemicals, including carbon dioxide, lactic acid, ammonia and octenol. Octenol is one of many carbon-based compounds that have a molecular structure that can take on either a "right-handed" or "left-handed" form. Each form is a mirror image of the other, and a form's "handedness" is determined by how its molecular bonds are assembled.
The scientists used frog eggs to help them make their discovery. They injected RNA from Ae. aegypti into the frog eggs, allowing the egg membranes to mimic the mosquito's ability to detect octenol. Then they attached microelectrodes to the frog egg cell membranes, passed octenol over them and recorded the electrical signals stimulated by the odors.
They ran the tests using both the right- and left-handed forms of octenol. The scientists found heightened electrical activity when the membrane was exposed to the right-handed form, and weakened activity when it was exposed to the left-handed form.
There are many natural compounds that can take on either a right-handed or left-handed form. While the effects of those differences on many plants and animals remains a mystery, the report, published in PLoS ONE, shows the effects of octenol's dual structure on the yellow fever mosquito and adds to scientists' understanding of how mosquitoes sense the world around them. It also may open the door to speedier development of better mosquito repellents and traps, according to Dickens.
The team's research is being funded by the Department of Defense Deployed War Fighter Protection Research Program.
ARS is the principal intramural scientific research agency of the U.S. Department of Agriculture.
USDA is an equal opportunity provider, employer and lender. To file a complaint of discrimination, write: USDA, Director, Office of Civil Rights, 1400 Independence Ave., S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice), or (202) 720-6382 (TDD).
Friday, January 01, 2010
Nominations Wanted for Jacobson Award for Physician Excellence
The Vascular Disease Foundation is seeking nominations for the 2010 Julius H. Jacobson II Award for Physician Excellence. The deadline for nominations is Friday, January 29, 2010.
The Julius H. Jacobson II MD Award for Physician Excellent is awarded annually by the Vascular Disease Foundation. This prestigious annual award recognizes outstanding contributions to physician education, leadership, or patient care in vascular disease. Dr. Jacobson is a pioneer in microsurgery and was the first physician to bring a microscope into the operating room. His work led to such advances as coronary artery surgery and limb reimplantation. Dr. Jacobson also developed the first microscope that allowed the surgeon and the first assistant to view the operative field simultaneously. This award is endowed through a donation from Dr. Jacobson.
Candidates for the Jacobson Award will be screened by a committee of peers independent of Dr. Jacobson. Nomination criteria are:
• Must be a licensed physician in good standing
• Has made significant contributions that have advanced the science or clinical
practice for the prevention and treatment of vascular disease or who has made exceptional contributions to vascular education programs, either to health professionals or patients.
• Must be a person of recognized personal and professional integrity.
• Must not be a current member of the Board of Directors of the Vascular Disease Foundation.
This year’s recipient was Dr. Jess R. Young. Dr. Young is one of the pioneers of vascular medicine and a premier educator in the field, training an entire generation of vascular medicine fellows. Dr. Young was pivotal in establishing the vascular diagnostic laboratory at the Cleveland Clinic. Perhaps one of the greatest visions by Dr. Young was the establishment of the first multi-specialty vascular intervention programs in the United States in the early 1990s. He also served as primary editor for the first edition of "A Textbook of Peripheral Vascular Disease," which remains one of the finest clinical textbooks of its kind. He has over 100 publications showing his depth of contribution to the field.
The Vascular Disease Foundation is seeking nominations for the 2010 Julius H. Jacobson II Award for Physician Excellence. The deadline for nominations is Friday, January 29, 2010.
The Julius H. Jacobson II MD Award for Physician Excellent is awarded annually by the Vascular Disease Foundation. This prestigious annual award recognizes outstanding contributions to physician education, leadership, or patient care in vascular disease. Dr. Jacobson is a pioneer in microsurgery and was the first physician to bring a microscope into the operating room. His work led to such advances as coronary artery surgery and limb reimplantation. Dr. Jacobson also developed the first microscope that allowed the surgeon and the first assistant to view the operative field simultaneously. This award is endowed through a donation from Dr. Jacobson.
Candidates for the Jacobson Award will be screened by a committee of peers independent of Dr. Jacobson. Nomination criteria are:
• Must be a licensed physician in good standing
• Has made significant contributions that have advanced the science or clinical
practice for the prevention and treatment of vascular disease or who has made exceptional contributions to vascular education programs, either to health professionals or patients.
• Must be a person of recognized personal and professional integrity.
• Must not be a current member of the Board of Directors of the Vascular Disease Foundation.
This year’s recipient was Dr. Jess R. Young. Dr. Young is one of the pioneers of vascular medicine and a premier educator in the field, training an entire generation of vascular medicine fellows. Dr. Young was pivotal in establishing the vascular diagnostic laboratory at the Cleveland Clinic. Perhaps one of the greatest visions by Dr. Young was the establishment of the first multi-specialty vascular intervention programs in the United States in the early 1990s. He also served as primary editor for the first edition of "A Textbook of Peripheral Vascular Disease," which remains one of the finest clinical textbooks of its kind. He has over 100 publications showing his depth of contribution to the field.
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