You might not know it but fertilizer is the explosive of choice for budget-conscious terrorists. The blasts at the World Trade Center in 1993, Oklahoma City Federal Building in 1995 and on rush-hour London buses and trains in 2005 all contained ammonium nitrate fertilizer (which is manufactured in bulk as an explosive by the U.S. and other countries as well as by companies.) [More]
You might not know it but fertilizer is the explosive of choice for budget-conscious terrorists. The blasts at the World Trade Center in 1993, Oklahoma City Federal Building in 1995 and on rush-hour London buses and trains in 2005 all contained ammonium nitrate fertilizer (which is manufactured in bulk as an explosive by the U.S. and other countries as well as by companies.) [More]
When materials scientist Joseph Michael and his team at Sandia National Laboratories in Albuquerque, N.M., trained their high-powered electron microscope on anthrax spore samples the FBI had sent them in February 2002, they made two crucial discoveries: The first confirmed previous findings that the Bacillus anthracis spores mailed to U.S. Senate offices and various media outlets (shortly after the September 11 terrorist attacks) contained silicon, a substance used to turn anthrax-causing spores into a biological weapon.
But it was Sandia's next discovery that marked a critical turning point in the feds's probe of the mysterious mailings, which killed five people, injured 17 and prompted thousands more who were potentially exposed to the deadly spores to take potent antibiotics--in particular, Ciprofloxacin (known to irritate the gastrointestinal tract and cause joint swelling). Using highly sensitive transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM), the researchers came to a startling realization: The silicon had grown organically inside the Bacillus anthracis samples, nothing had been added to weaponize the spores. "The silicon was not on the outside of the spore," says Michael, who headed up Sandia's investigation, "but rather incorporated on the inside."
[More]When materials scientist Joseph Michael and his team at Sandia National Laboratories in Albuquerque, N.M., trained their high-powered electron microscope on anthrax spore samples the FBI had sent them in February 2002, they made two crucial discoveries: The first confirmed previous findings that the Bacillus anthracis spores mailed to U.S. Senate offices and various media outlets (shortly after the September 11 terrorist attacks) contained silicon, a substance used to turn anthrax-causing spores into a biological weapon.
But it was Sandia's next discovery that marked a critical turning point in the feds's probe of the mysterious mailings, which killed five people, injured 17 and prompted thousands more who were potentially exposed to the deadly spores to take potent antibiotics--in particular, Ciprofloxacin (known to irritate the gastrointestinal tract and cause joint swelling). Using highly sensitive transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM), the researchers came to a startling realization: The silicon had grown organically inside the Bacillus anthracis samples, nothing had been added to weaponize the spores. "The silicon was not on the outside of the spore," says Michael, who headed up Sandia's investigation, "but rather incorporated on the inside."
[More][The following is an exact transcript of this podcast.]
[More][The following is an exact transcript of this podcast.]
[More]Escherichia coli (E. coli) can give you a severe case of food poisoning or, with a little genetic engineering, a useful plastic. Scientists at San Diego–based Genomatica, Inc., have announced success in manipulating the bacteria to directly produce butanediol (BDO), a chemical compound used to make everything from spandex to car bumpers, thereby providing a more energy-efficient way of making it without oil or natural gas. [More]
Escherichia coli (E. coli) can give you a severe case of food poisoning or, with a little genetic engineering, a useful plastic. Scientists at San Diego–based Genomatica, Inc., have announced success in manipulating the bacteria to directly produce butanediol (BDO), a chemical compound used to make everything from spandex to car bumpers, thereby providing a more energy-efficient way of making it without oil or natural gas. [More]
[The following is an exact transcript of this podcast.]
[More][The following is an exact transcript of this podcast.]
[More]Editor's Note: This story was originally published in the February 1999 edition of Scientific American. We are posting it in light of recent news involving Lehman Brothers and Merrill Lynch.
Individual investors and professional stock and currency traders know better than ever that prices quoted in any financial market often change with heart-stopping swiftness. Fortunes are made and lost in sudden bursts of activity when the market seems to speed up and the volatility soars. Last September, for instance, the stock for Alcatel, a French telecommunications equipment manufacturer, dropped about 40 percent one day and fell another 6 percent over the next few days. In a reversal, the stock shot up 10 percent on the fourth day.
[More]Editor's Note: This story was originally published in the February 1999 edition of Scientific American. We are posting it in light of recent news involving Lehman Brothers and Merrill Lynch.
Individual investors and professional stock and currency traders know better than ever that prices quoted in any financial market often change with heart-stopping swiftness. Fortunes are made and lost in sudden bursts of activity when the market seems to speed up and the volatility soars. Last September, for instance, the stock for Alcatel, a French telecommunications equipment manufacturer, dropped about 40 percent one day and fell another 6 percent over the next few days. In a reversal, the stock shot up 10 percent on the fourth day.
[More]More than 15 million Americans drink too much, according to the National Institute on Alcohol Abuse and Alcoholism. New research on rats may help them curb that addiction. [More]
More than 15 million Americans drink too much, according to the National Institute on Alcohol Abuse and Alcoholism. New research on rats may help them curb that addiction. [More]
An alcohol-busting enzyme may help prevent heart attack damage, according to a new study in Science. Researchers report that aldehyde dehydrogenase 2 (ALDH2), an enzyme important for processing alcohol in the human body, clears harmful toxins produced in cells when blood flow is blocked in the heart--and a new drug can switch it on. [More]
An alcohol-busting enzyme may help prevent heart attack damage, according to a new study in Science. Researchers report that aldehyde dehydrogenase 2 (ALDH2), an enzyme important for processing alcohol in the human body, clears harmful toxins produced in cells when blood flow is blocked in the heart--and a new drug can switch it on. [More]
A new grenadelike gadget--designed to quickly extinguish flames in small quarters, thereby limiting injury to victims as well as firefighters--is becoming an important part of firemen's arsenals. [More]
A new grenadelike gadget--designed to quickly extinguish flames in small quarters, thereby limiting injury to victims as well as firefighters--is becoming an important part of firemen's arsenals. [More]
Dear EarthTalk: What’s the deal nowadays with aerosol spray cans? I thought that the ozone-depleting chemicals used in them were eliminated back in the 1970s. Is this true? If so, what is now used as a propellant? Are aerosols still bad for the ozone layer? -- Sheila, Abilene, TX
[More]Dear EarthTalk: What’s the deal nowadays with aerosol spray cans? I thought that the ozone-depleting chemicals used in them were eliminated back in the 1970s. Is this true? If so, what is now used as a propellant? Are aerosols still bad for the ozone layer? -- Sheila, Abilene, TX
[More]Within hours of his demise in 1955, Albert Einstein’s brain was salvaged, sliced into 240 pieces and stored in jars for safekeeping. Since then, researchers have weighed, measured and otherwise inspected these biological specimens of genius in hopes of uncovering clues to Einstein’s spectacular intellect.
Their cerebral explorations are part of a century-long effort to uncover the neural basis of high intelligence or, in children, giftedness. Traditionally, 2 to 5 percent of kids qualify as gifted, with the top 2 percent scoring above 130 on an intelligence quotient (IQ) test. (The statistical average is 100. See the box on the opposite page.) A high IQ increases the probability of success in various academic areas. Children who are good at reading, writing or math also tend to be facile at the other two areas and to grow into adults who are skilled at diverse intellectual tasks [see “Solving the IQ Puzzle,” by James R. Flynn; Scientific American Mind, October/November 2007].
[More]Within hours of his demise in 1955, Albert Einstein’s brain was salvaged, sliced into 240 pieces and stored in jars for safekeeping. Since then, researchers have weighed, measured and otherwise inspected these biological specimens of genius in hopes of uncovering clues to Einstein’s spectacular intellect.
Their cerebral explorations are part of a century-long effort to uncover the neural basis of high intelligence or, in children, giftedness. Traditionally, 2 to 5 percent of kids qualify as gifted, with the top 2 percent scoring above 130 on an intelligence quotient (IQ) test. (The statistical average is 100. See the box on the opposite page.) A high IQ increases the probability of success in various academic areas. Children who are good at reading, writing or math also tend to be facile at the other two areas and to grow into adults who are skilled at diverse intellectual tasks [see “Solving the IQ Puzzle,” by James R. Flynn; Scientific American Mind, October/November 2007].
[More][The following is an exact transcript of this podcast.]
[Spray sound.] Killing bugs? No. [Spray sound.] Deodorizing the bathroom? No. [Spray sound.] Checking for explosives, yes. Because chemists at the University of California, San Diego have come up with a spray-on polymer film that can spot residue from nitrogen-based explosives such as TNT. It works in as little as 30 seconds.
[More][The following is an exact transcript of this podcast.]
[Spray sound.] Killing bugs? No. [Spray sound.] Deodorizing the bathroom? No. [Spray sound.] Checking for explosives, yes. Because chemists at the University of California, San Diego have come up with a spray-on polymer film that can spot residue from nitrogen-based explosives such as TNT. It works in as little as 30 seconds.
[More]Can one neuron release more than one neurotransmitter?--Marvin Shrewsbury, Wailuku, Hawaii
[More]Can one neuron release more than one neurotransmitter?--Marvin Shrewsbury, Wailuku, Hawaii
[More]TOMSK, RUSSIA--After a half century of neglect, a search for better drugs and diagnostics to treat tuberculosis (TB) is underway. But progress is slow, and the breakthroughs that will help reduce the global burden of TB remain years away.
The modern diagnostics lab under construction in this Siberian capital is a good example. It will shorten the time it takes to identify a case of multidrug resistant (MDR) tuberculosis from two to three months to two or three weeks by using liquid media instead of solid media to grow individuals' samples of M. tuberculosis and test them for resistance to first-line treatments. MDR-TB accounts for a shockingly high 15 percent of cases here, and its misdiagnosis almost always leads to treatment failure.
[More]TOMSK, RUSSIA--After a half century of neglect, a search for better drugs and diagnostics to treat tuberculosis (TB) is underway. But progress is slow, and the breakthroughs that will help reduce the global burden of TB remain years away.
The modern diagnostics lab under construction in this Siberian capital is a good example. It will shorten the time it takes to identify a case of multidrug resistant (MDR) tuberculosis from two to three months to two or three weeks by using liquid media instead of solid media to grow individuals' samples of M. tuberculosis and test them for resistance to first-line treatments. MDR-TB accounts for a shockingly high 15 percent of cases here, and its misdiagnosis almost always leads to treatment failure.
[More]MELNIKOVO, RUSSIA--To properly treat tuberculosis (TB), you must take up to four antibiotics every day for six months under careful supervision. If you are one of the 17 stricken individuals in this small farming community, you can get that care either at the clinic–hospital in the town center or one of the newly opened satellite clinics in outlying neighborhoods.
But none of those were accessible to 85-year-old Lubov Potaskaeva, who lives in a rundown apartment complex for agricultural laborers far from town. The Kyrgyzstani native has no idea how she caught the disease. She only knows that when she was screened for TB as part of her application to enter the area's retirement home--she wanted in because she was always short of breath and could no longer climb the stairs to her second-floor apartment--her test came back positive.
[More]MELNIKOVO, RUSSIA--To properly treat tuberculosis (TB), you must take up to four antibiotics every day for six months under careful supervision. If you are one of the 17 stricken individuals in this small farming community, you can get that care either at the clinic–hospital in the town center or one of the newly opened satellite clinics in outlying neighborhoods.
But none of those were accessible to 85-year-old Lubov Potaskaeva, who lives in a rundown apartment complex for agricultural laborers far from town. The Kyrgyzstani native has no idea how she caught the disease. She only knows that when she was screened for TB as part of her application to enter the area's retirement home--she wanted in because she was always short of breath and could no longer climb the stairs to her second-floor apartment--her test came back positive.
[More][The following is an exact transcript of this podcast.]
[More][The following is an exact transcript of this podcast.]
[More]A tangle of tubes and polyurethane pouches binds a naked man and woman--he, paunchy and unperturbed, she, slim and similarly unself-conscious. This setup is not some esoteric sex game; it’s “Smell Blind Date,” an installation created by artist James Auger on display this past spring in New York City as part of the Museum of Modern Art’s exhibition Design and the Elastic Mind. The PVC tubes--which run between the subjects’ chests, with outlets extending to pouches attached to their noses, armpits and genitals--allow the man and woman to inhale each other’s body odor through a wall that divides them. In theory, they are on a truly blind date, each undistracted by the other’s looks, assessing the other’s potential as a mating partner by his or her smell alone.
The human sense of smell is often seen as insignificant, dismissed as a distant also-ran to our keen eyesight or sensitive hearing. But this sense is keener and more influential on our species than many people realize. In particular, as Auger’s fanciful art project illustrates, smell facilitates a variety of human social interactions, both casual and intimate. Indeed, people who lose their sense of smell often gain a new appreciation for its importance [see “When the Nose Doesn’t Know,” by Eleonore von Bothmer; Scientific American Mind, October/November 2006].
[More]A tangle of tubes and polyurethane pouches binds a naked man and woman--he, paunchy and unperturbed, she, slim and similarly unself-conscious. This setup is not some esoteric sex game; it’s “Smell Blind Date,” an installation created by artist James Auger on display this past spring in New York City as part of the Museum of Modern Art’s exhibition Design and the Elastic Mind. The PVC tubes--which run between the subjects’ chests, with outlets extending to pouches attached to their noses, armpits and genitals--allow the man and woman to inhale each other’s body odor through a wall that divides them. In theory, they are on a truly blind date, each undistracted by the other’s looks, assessing the other’s potential as a mating partner by his or her smell alone.
The human sense of smell is often seen as insignificant, dismissed as a distant also-ran to our keen eyesight or sensitive hearing. But this sense is keener and more influential on our species than many people realize. In particular, as Auger’s fanciful art project illustrates, smell facilitates a variety of human social interactions, both casual and intimate. Indeed, people who lose their sense of smell often gain a new appreciation for its importance [see “When the Nose Doesn’t Know,” by Eleonore von Bothmer; Scientific American Mind, October/November 2006].
[More]Arsenic, a deadly poison, kills by blocking the ability of cells to produce and consume energy. Yet, some red and green slime mats in briny hot springs in Mono Lake, Calif., use the potent compound rather than water to carry energy during photosynthesis (the process used by bacteria and plants that converts sunlight into food) new research in Science reveals. [More]
Arsenic, a deadly poison, kills by blocking the ability of cells to produce and consume energy. Yet, some red and green slime mats in briny hot springs in Mono Lake, Calif., use the potent compound rather than water to carry energy during photosynthesis (the process used by bacteria and plants that converts sunlight into food) new research in Science reveals. [More]
More bad news for the world's oceans: Dead zones--areas of bottom waters too oxygen depleted to support most ocean life--are spreading, dotting nearly the entire east and south coasts of the U.S. as well as several west coast river outlets.
According to a new study in Science, the rest of the world fares no better--there are now 405 identified dead zones worldwide, up from 49 in the 1960s--and the world's largest dead zone remains the Baltic Sea, whose bottom waters now lack oxygen year-round.
[More]More bad news for the world's oceans: Dead zones--areas of bottom waters too oxygen depleted to support most ocean life--are spreading, dotting nearly the entire east and south coasts of the U.S. as well as several west coast river outlets.
According to a new study in Science, the rest of the world fares no better--there are now 405 identified dead zones worldwide, up from 49 in the 1960s--and the world's largest dead zone remains the Baltic Sea, whose bottom waters now lack oxygen year-round.
[More][The following is an exact transcript of this podcast.]
Laundry detergents and air fresheners have long promised to keep your house and clothes smelling sunshine fresh and rain shower clean. But what they haven't said is what exactly you're sniffing when you snuggle up in your just-washed sheets. After hearing from people who said strong scents made them sick, University of Washington researcher Anne Steinemann scratched the surface and found almost a hundred chemicals that weren't listed on the labels. According to her report in the journal Environmental Impact Assessment Review, plug-in air fresheners, scented sprays, dryer sheets and detergents all contained a mixture of volatile organic compounds. [More]
[The following is an exact transcript of this podcast.]
Laundry detergents and air fresheners have long promised to keep your house and clothes smelling sunshine fresh and rain shower clean. But what they haven't said is what exactly you're sniffing when you snuggle up in your just-washed sheets. After hearing from people who said strong scents made them sick, University of Washington researcher Anne Steinemann scratched the surface and found almost a hundred chemicals that weren't listed on the labels. According to her report in the journal Environmental Impact Assessment Review, plug-in air fresheners, scented sprays, dryer sheets and detergents all contained a mixture of volatile organic compounds. [More]