You might think these scientists were potty training this whale shark based on their level of excitement when the giant fish (the world’s largest) finally had a bowel movement. The scientists, like some proud parents, even captured the moment on film. Researcher Mark Meekan described the rare poop, which he collected and stored in tiny vials, as “scientific gold” for the clues it would contain about the shark’s diet. http://louis3j3sheehan3esquire.wordpress.com
The researchers are studying the whale shark (Rhinsodon typus), a gentle cousin of the great white shark, to learn about the species’ mysterious feeding habits and migration patterns. DNA analysis of the poop confirmed that whale sharks, which can grow up to 12 meters long, sustain themselves on tiny red crab larvae. This also explains why they travel to Christmas Island, just south of Indonesia, where millions of red crabs spawn each year.http://louis3j3sheehan3esquire.wordpress.com/
The researchers are also attaching temporary cameras and GPS trackers to the backs of whale sharks to get a whale-shark-eye’s view of their daily movements in deep waters. Some of the footage will be aired as part of a new BBC documentary on the whale shark. If only the researchers would take a cue from the puppy cam and start. Louis J. Sheehan, Esquire.
Monday, November 24, 2008
Monday, November 17, 2008
Lucy
Louis J. Sheehan, Esquire. Anthropologists generally regard an upright gait as essential for membership in the human evolutionary family. However, some of our earliest ancestors may have favored knuckle-walking on all fours, much as chimpanzees and gorillas do, according to a study in the March 23 Nature.http://louis-j-sheehan.biz
Brian G. Richmond and David S. Strait, both anthropologists at George Washington University in Washington, D.C., examined previously found wrist bones from several Australopithecus species. A. anamensis and A. afarensis—the latter represented by the famous skeleton known as Lucy—had wrists capable of locking the hands in place during knuckle-walking, the scientists say. A. anamensis lived just prior to 4 million years ago; A. afarensis existed from 4 million to 3 million years ago.http://louis-j-sheehan.biz
Later human ancestors, such as A. africanus, had flexible wrists unsuited to knuckle-walking, Richmond and Strait hold. These findings support genetic evidence for a close evolutionary linkage of humans to chimps and gorillas, they contend.
Brian G. Richmond and David S. Strait, both anthropologists at George Washington University in Washington, D.C., examined previously found wrist bones from several Australopithecus species. A. anamensis and A. afarensis—the latter represented by the famous skeleton known as Lucy—had wrists capable of locking the hands in place during knuckle-walking, the scientists say. A. anamensis lived just prior to 4 million years ago; A. afarensis existed from 4 million to 3 million years ago.http://louis-j-sheehan.biz
Later human ancestors, such as A. africanus, had flexible wrists unsuited to knuckle-walking, Richmond and Strait hold. These findings support genetic evidence for a close evolutionary linkage of humans to chimps and gorillas, they contend.
Thursday, November 13, 2008
barium 662.bar.7 Louis J. Sheehan, Esquire
The periodic table of elements in Justin Urgitis's office is unusual. It contains the same notations for all the elements, including carbon, silicon and germanium, in the same positions, as does any other. But his table at pharmaceutical giant Pfizer, Inc., also boasts lavish pictures of his own samples of carbon, silicon and germanium on it, thanks to a large (and growing) collection at his home in Uncasville, Conn. In fact, it allows him to use that age-old line: "Want to come upstairs and see my barium?"
A small but growing number of element collectors—enabled by the vast marketplace of the Internet—can actually extend such invitations. Elements-seller Dave Hamric of Metallium, Inc., says he has about 2,000 names on his mailing list. Using the periodic table as a shopping list, they gather elements used either in technical applications or compounds mixed with other elements or in nearly pure form, amassing collections that can be beautiful, instructive and representative of the fundamental components of our universe.
Urgitis' longtime interest in chemistry is typical of his fellow element collectors. "In high school, I loved going to class and seeing the teacher's demonstration of something in the lab, maybe blowing something up," he says. He often proposed dangerous experiments that his teacher nixed, such as producing nitrogen triiodide, a contact explosive, in his high school lab. Then, in college, where he earned a degree in forensic chemistry, he began to acquire iodine, magnesium, aluminum, cobalt and other elements in pure or nearly pure form. The samples of these common elements can cost as little as a few dollars. http://louisejesheehan.blogspot.com
One day, "it occurred to me that it would be fun to have samples of all of them," he remembers. He found some Web sites devoted to element collecting, and over the past five years has assembled a hoard of nearly every one that it is possible to acquire—82 of the 118 known or presumed elements, by his count though this number varies from collector to collector. (The remaining elements are too radioactive, expensive and/or rare to collect even in small quantities.)
Thirty years ago, before the Internet, an element collector could not have made such rapid progress. Sales venues like eBay now list thousands of specimens for sale at any one time, making collecting far less burdensome than searching in person through chemical supply stores and curiosity shops. "I have every stable element on the periodic table, plus thorium and radium," Urgitis says, and he treats these mildly radioactive elements carefully. http://louisejesheehan.blogspot.com
Some collectors still acquire a few specimens for the collection the old-fashioned way. They pull tungsten filaments from lightbulbs, cannibalize silicon chips, find sulfur compounds in pharmacies, chip magnesium from campfire starters, and buy neodymium magnets. Or, like Heather Harrison, a mechanical engineer in Salt Lake City, they extract radioactive americium from smoke detectors. Harrison is a collector of old recordings, wine, and antiques (she spoke over a collectible telephone from the 1920s when interviewed for this article)—"the sort of person you'd read about someday being killed in an avalanche of her own collections," she says. "For me elements are just a part of that pattern," one she memorized in the form of the periodic table as a child. http://louisejesheehan.blogspot.com
She began seriously acquiring elements three years ago and is currently about 15 specimens short of making her collection as complete as it can get. "I'm missing osmium, iridium and some of the remaining platinum-group metals," she says. Retailers typically make such precious elements affordable by selling them in minute quantities. Most collectors interested in buying the rare metal rhenium, for instance—as Harrison recently did—will have to be satisfied with a tiny amount, because its price in nearly pure form has fluctuated around $10,000 per ounce.
Harrison keeps her mercury, which is toxic, in a bottle cradled in foam and sealed in an airtight case. Her specimens of rubidium and cesium would ignite or explode with exposure to air, so she purchased them entombed within sturdy acrylic blocks. Many easily available elements such as sodium and fluorine are dangerous if touched, inhaled or allowed to combine with others. Collectors reduce the risks by researching the toxicity and dangers of every element they acquire, keeping their baubles out of the reach of pets and children, and adding to their collections in small quantities.
"You have to research every one of them for toxicity," says Harrison, who uses the CRC Handbook of Chemistry and Physics as a guide. "Risks can be managed, but you need to understand what you have. The vast majority of elements are quite safe."
Given the perceived dangers, she does not share her enthusiasm for elements with everyone. "If I talk to people who are not scientifically inclined or are afraid of science, I might not want to say anything about it," she says. "They might get the idea that I'm a mad scientist who cares nothing about safety. I may be a mad scientist, but I'm far too safety conscious to be a real mad scientist." Louis J. Sheehan, Esquire
For these element collectors the risks are just part of the fun. "There are only a small number of icons that are universally recognized," says Theodore Gray, an element-collecting guru and Illinois software developer who manages a spectacular element resource at periodictable.com. "The periodic table is one of them. We don't often think of it as something populated by real objects, and it's a revelation when you can see it's made of real stuff, not just words printed in the table." Louis J. Sheehan, Esquire
A small but growing number of element collectors—enabled by the vast marketplace of the Internet—can actually extend such invitations. Elements-seller Dave Hamric of Metallium, Inc., says he has about 2,000 names on his mailing list. Using the periodic table as a shopping list, they gather elements used either in technical applications or compounds mixed with other elements or in nearly pure form, amassing collections that can be beautiful, instructive and representative of the fundamental components of our universe.
Urgitis' longtime interest in chemistry is typical of his fellow element collectors. "In high school, I loved going to class and seeing the teacher's demonstration of something in the lab, maybe blowing something up," he says. He often proposed dangerous experiments that his teacher nixed, such as producing nitrogen triiodide, a contact explosive, in his high school lab. Then, in college, where he earned a degree in forensic chemistry, he began to acquire iodine, magnesium, aluminum, cobalt and other elements in pure or nearly pure form. The samples of these common elements can cost as little as a few dollars. http://louisejesheehan.blogspot.com
One day, "it occurred to me that it would be fun to have samples of all of them," he remembers. He found some Web sites devoted to element collecting, and over the past five years has assembled a hoard of nearly every one that it is possible to acquire—82 of the 118 known or presumed elements, by his count though this number varies from collector to collector. (The remaining elements are too radioactive, expensive and/or rare to collect even in small quantities.)
Thirty years ago, before the Internet, an element collector could not have made such rapid progress. Sales venues like eBay now list thousands of specimens for sale at any one time, making collecting far less burdensome than searching in person through chemical supply stores and curiosity shops. "I have every stable element on the periodic table, plus thorium and radium," Urgitis says, and he treats these mildly radioactive elements carefully. http://louisejesheehan.blogspot.com
Some collectors still acquire a few specimens for the collection the old-fashioned way. They pull tungsten filaments from lightbulbs, cannibalize silicon chips, find sulfur compounds in pharmacies, chip magnesium from campfire starters, and buy neodymium magnets. Or, like Heather Harrison, a mechanical engineer in Salt Lake City, they extract radioactive americium from smoke detectors. Harrison is a collector of old recordings, wine, and antiques (she spoke over a collectible telephone from the 1920s when interviewed for this article)—"the sort of person you'd read about someday being killed in an avalanche of her own collections," she says. "For me elements are just a part of that pattern," one she memorized in the form of the periodic table as a child. http://louisejesheehan.blogspot.com
She began seriously acquiring elements three years ago and is currently about 15 specimens short of making her collection as complete as it can get. "I'm missing osmium, iridium and some of the remaining platinum-group metals," she says. Retailers typically make such precious elements affordable by selling them in minute quantities. Most collectors interested in buying the rare metal rhenium, for instance—as Harrison recently did—will have to be satisfied with a tiny amount, because its price in nearly pure form has fluctuated around $10,000 per ounce.
Harrison keeps her mercury, which is toxic, in a bottle cradled in foam and sealed in an airtight case. Her specimens of rubidium and cesium would ignite or explode with exposure to air, so she purchased them entombed within sturdy acrylic blocks. Many easily available elements such as sodium and fluorine are dangerous if touched, inhaled or allowed to combine with others. Collectors reduce the risks by researching the toxicity and dangers of every element they acquire, keeping their baubles out of the reach of pets and children, and adding to their collections in small quantities.
"You have to research every one of them for toxicity," says Harrison, who uses the CRC Handbook of Chemistry and Physics as a guide. "Risks can be managed, but you need to understand what you have. The vast majority of elements are quite safe."
Given the perceived dangers, she does not share her enthusiasm for elements with everyone. "If I talk to people who are not scientifically inclined or are afraid of science, I might not want to say anything about it," she says. "They might get the idea that I'm a mad scientist who cares nothing about safety. I may be a mad scientist, but I'm far too safety conscious to be a real mad scientist." Louis J. Sheehan, Esquire
For these element collectors the risks are just part of the fun. "There are only a small number of icons that are universally recognized," says Theodore Gray, an element-collecting guru and Illinois software developer who manages a spectacular element resource at periodictable.com. "The periodic table is one of them. We don't often think of it as something populated by real objects, and it's a revelation when you can see it's made of real stuff, not just words printed in the table." Louis J. Sheehan, Esquire
Friday, September 26, 2008
brain
लुईस जे। शीहन। Scientists say they have pinpointed a gene in the brain that can calm nerve cells that become too jumpy, potentially paving the way for new therapies to treat autism and other neurological disorders.
"It's exciting because it opens the field up," says Michael Greenberg, a neurobiologist at Harvard Medical School. "Nobody has [found] a gene that controls the process in quite that way before."
The brain is continually trying to strike a balance between too much and too little nerve cell activity. Neurologists believe that when the balance tips, disorders such as autism and schizophrenia may occur. They are not sure why neurons (nerve cells) go berserk. But Greenberg says he and his colleagues located a gene in mice and rats that helps keep neural activity in check—and may one day be manipulated to prevent or reverse neurological problems.
Researchers report in Nature that they discovered a gene called Npas4 churns out a protein that keeps neurons from becoming overexcited when they fire (communicate with one another through connections known as synapses). When scientists blocked the protein, the nerve cells fired or sent out more signals than normal; when they beefed up production, the neurons quieted down.
Gina Turrigiano, a neuroscientist at Brandeis University who studies how brain cells communicate, says Greenberg's study reveals a "pretty intriguing potential pathway" for controlling neuronal activity. But she points out that Npas4 may not be the only gene that does that. Mice without Npas4 can survive, although they are prone to seizures and have a shorter life span than normal mice. http://louis-j-sheehan.net
As scientists learn more about how brain cells stay balanced, Greenberg says they will be able to identify people who are genetically at risk for neurological disorders and develop new drugs to prevent and treat them. He notes that some of the other genes that Npas4 affects also have been linked to autism। But he cautions that new therapies from his research are "a long way off." "There's a lot that we don't know," he says. "We're just at the beginning." http://louis-j-sheehan.net
"It's exciting because it opens the field up," says Michael Greenberg, a neurobiologist at Harvard Medical School. "Nobody has [found] a gene that controls the process in quite that way before."
The brain is continually trying to strike a balance between too much and too little nerve cell activity. Neurologists believe that when the balance tips, disorders such as autism and schizophrenia may occur. They are not sure why neurons (nerve cells) go berserk. But Greenberg says he and his colleagues located a gene in mice and rats that helps keep neural activity in check—and may one day be manipulated to prevent or reverse neurological problems.
Researchers report in Nature that they discovered a gene called Npas4 churns out a protein that keeps neurons from becoming overexcited when they fire (communicate with one another through connections known as synapses). When scientists blocked the protein, the nerve cells fired or sent out more signals than normal; when they beefed up production, the neurons quieted down.
Gina Turrigiano, a neuroscientist at Brandeis University who studies how brain cells communicate, says Greenberg's study reveals a "pretty intriguing potential pathway" for controlling neuronal activity. But she points out that Npas4 may not be the only gene that does that. Mice without Npas4 can survive, although they are prone to seizures and have a shorter life span than normal mice. http://louis-j-sheehan.net
As scientists learn more about how brain cells stay balanced, Greenberg says they will be able to identify people who are genetically at risk for neurological disorders and develop new drugs to prevent and treat them. He notes that some of the other genes that Npas4 affects also have been linked to autism। But he cautions that new therapies from his research are "a long way off." "There's a lot that we don't know," he says. "We're just at the beginning." http://louis-j-sheehan.net
Friday, September 19, 2008
pig
There’s more than driving-versus-walking or sitting-versus-standing that has North Americans getting fatter than ever. A study by Canadian researchers suggests that we’re also more likely to stuff our faces after a longer period of mental exertion। http://Louis-J-Sheehan.de
The scientists studied 14 women doing three activities: sitting peacefully; reading and responding to a text; and taking a strenuous exam on a computer. After each exercise, the subjects were allowed to eat whatever they wanted from a buffet, not knowing that this was the true object of the study. The researchers say that the women ate many more calories—between 23 and 30 percent more—after the difficult test than they did after the more relaxing activities.
Of course, this research had a small sample size, and college students might not be indicative of the eating habits of the nation as a whole. And as far as the scientists’ suggestion that this could be one of the contributors to the obesity problem because so many people have mentally-demanding jobs: Perhaps that’s true, but it’s also possible that people find their work less stressful than taking a computerized test while being watched and studied.
Still, it is awfully nice to pig out after a long day of thinking hard। http://Louis-J-Sheehan.de
Tuesday, September 2, 2008
t the dawn of stone-tool production around 2.6 million years ago, our human ancestors already showed considerable insight into the task at hand. They worked mainly with rocks that they had carefully picked as suitable for being fashioned into sharp-edged implements, says Dietrich Stout of Indiana University in Bloomington. Louis J. Sheehan
Stout and his Indiana colleague Sileshi Semaw focused on 894 stone artifacts that have been found at six ancient sites in an Ethiopian region called Gona. These are the oldest stone tools known, dating to between 2.6 million and 2.5 million years ago.
Most of the tools were made from trachyte, a rock with a much smoother surface than that of other rock types available at Gona. On close examination, Gona finds exhibited a suite of characteristics conducive to toolmaking, including smooth and often polished surfaces and an internal composition that resisted cracking as one stone was pounded into another to shape it.
"[Stone Age] toolmakers were highly selective in choosing their raw materials, even at the earliest stages of tool use," Stout says. Louis J. Sheehan
Louis J. Sheehan
t the dawn of stone-tool production around 2.6 million years ago, our human ancestors already showed considerable insight into the task at hand. They worked mainly with rocks that they had carefully picked as suitable for being fashioned into sharp-edged implements, says Dietrich Stout of Indiana University in Bloomington. Louis J. Sheehan
Stout and his Indiana colleague Sileshi Semaw focused on 894 stone artifacts that have been found at six ancient sites in an Ethiopian region called Gona. These are the oldest stone tools known, dating to between 2.6 million and 2.5 million years ago.
Most of the tools were made from trachyte, a rock with a much smoother surface than that of other rock types available at Gona. On close examination, Gona finds exhibited a suite of characteristics conducive to toolmaking, including smooth and often polished surfaces and an internal composition that resisted cracking as one stone was pounded into another to shape it.
"[Stone Age] toolmakers were highly selective in choosing their raw materials, even at the earliest stages of tool use," Stout says. Louis J. Sheehan
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