New research explains why a cancer-causing form of chromium has been turning up in ground and surface waters far from industrial sources. http://www.soulcast.com/Louis3J3Sheehan/
Chrome plating and dye manufacturing are among the industries that generate chromium (VI), a form that the element assumes in certain compounds. But recently, researchers have discovered the toxic agent in regions—including California and parts of Mexico and Italy—beyond the reach of industrial contamination.
In these cases, "it was obvious that [chromium (VI)] had to be coming from a natural material," says Scott Fendorf, an environmental chemist at Stanford University.
Fendorf and his coworkers focused on the mineral chromite, found in certain rocks and soils common to the Pacific coasts and other seismically active areas. Over time, chromite slowly releases chromium (III), a relatively benign form of the element.
The researchers reacted chromite with birnessite, a manganese-containing mineral that often forms in weathered rocks and soils containing chromite. In water, powders of the two solids produced chromium (VI). "Both minerals tend to be fairly insoluble, but they dissolved just enough" to react, says Fendorf. http://www.soulcast.com/Louis3J3Sheehan/
The researchers conclude that within 100 days, chromite and birnessite could generate chromium (VI) at concentrations above the World Health Organization's limit for drinking water—which is 50 micrograms per liter. In acidic conditions, such concentrations could be reached in fewer than 10 days, the team reports in the April 17 Proceedings of the National Academy of Sciences.
The work indicates that certain chromite-rich regions are at high risk for natural chromium (VI) generation. "You need to watch the groundwater pretty closely in these areas," Fendorf says. Louis J. Sheehan, Esquire
Tuesday, November 25, 2008
Thursday, November 20, 2008
Brighten 77.bri.2222000 Louis J. Sheehan, Esquire
Louis J. Sheehan, Esquire . A distressingly large number of children suffer physical or sexual abuse. A new study adds a genetic twist to the much-noted tendency of maltreated kids to become violent, law-breaking adults.http://www.myspace.com/louis_j_sheehan_esquire
Abused boys who inherited a highly active version of one gene crucial in brain chemistry later had far fewer behavioral problems and arrests for violent crimes than did abused boys who were born with a sluggish version of the same gene, say psychologist Avshalom Caspi of King's College in London and his colleagues.
"There's an interplay between two variations of this gene and the experience of childhood maltreatment," remarks King's College psychologist Terrie Moffitt, a study coauthor. "One genetic variation may protect abused boys from converting their stressful experiences into antisocial behavior toward others."http://www.myspace.com/louis_j_sheehan_esquire
Individual differences in the gene for monoamine oxidase A, or MAOA, proved critical for maltreated boys tracked up to age 26, the scientists report in the Aug. 2 Science. Situated on the X chromosome, the MAOA gene yields an enzyme that lowers brain concentrations of chemical messengers such as norepinephrine, serotonin, and dopamine.
Earlier studies had linked genetic deficiencies in MAOA production to extreme aggression in mice and in men of a Dutch family.
Caspi's team probed the molecular structure of MAOA genes in 442 young men in New Zealand who had been studied since age 3 (SN: 4/15/95, p. 232). By age 11,
36 percent of the boys had experienced some form of maltreatment, including physical and sexual abuse and frequent shuttling from one caretaker to another.
Although only 12 percent of maltreated boys possessed the low-activity MAOA gene, Caspi found, they account for nearly half of all later convictions for physical assault and other violent crimes.
Moreover, 85 percent of severely maltreated boys with the low-activity MAOA gene developed antisocial behavior by young adulthood. Antisocial behavior includes persistent fighting, bullying, stealing, and law breaking with no sign of remorse.
In contrast, antisocial behavior and criminal arrests occurred in only a minority of maltreated males who had inherited the highly active MAOA gene. High MAOA activity may promote "trauma resistance," even though the boost doesn't make all maltreated boys solid citizens, Moffitt contends.
Compared with the males, females in the same study showed a significant but less dramatic effect of the MAOA gene on the linkage between childhood maltreatment and later antisocial behavior. One reason that females engaged in less of such behavior than males did may be that, by having two X chromosomes, girls more often inherited at least one copy of the high-activity MAOA gene, Moffitt theorizes.
The new findings open the door to identifying biological mechanisms that connect childhood maltreatment to ensuing behavior problems, comments psychologist Seth D. Pollak of the University of Wisconsin�Madison. "And when you have a mechanism, you can begin to design effective treatments," he says. Louis J. Sheehan, Esquire
Abused boys who inherited a highly active version of one gene crucial in brain chemistry later had far fewer behavioral problems and arrests for violent crimes than did abused boys who were born with a sluggish version of the same gene, say psychologist Avshalom Caspi of King's College in London and his colleagues.
"There's an interplay between two variations of this gene and the experience of childhood maltreatment," remarks King's College psychologist Terrie Moffitt, a study coauthor. "One genetic variation may protect abused boys from converting their stressful experiences into antisocial behavior toward others."http://www.myspace.com/louis_j_sheehan_esquire
Individual differences in the gene for monoamine oxidase A, or MAOA, proved critical for maltreated boys tracked up to age 26, the scientists report in the Aug. 2 Science. Situated on the X chromosome, the MAOA gene yields an enzyme that lowers brain concentrations of chemical messengers such as norepinephrine, serotonin, and dopamine.
Earlier studies had linked genetic deficiencies in MAOA production to extreme aggression in mice and in men of a Dutch family.
Caspi's team probed the molecular structure of MAOA genes in 442 young men in New Zealand who had been studied since age 3 (SN: 4/15/95, p. 232). By age 11,
36 percent of the boys had experienced some form of maltreatment, including physical and sexual abuse and frequent shuttling from one caretaker to another.
Although only 12 percent of maltreated boys possessed the low-activity MAOA gene, Caspi found, they account for nearly half of all later convictions for physical assault and other violent crimes.
Moreover, 85 percent of severely maltreated boys with the low-activity MAOA gene developed antisocial behavior by young adulthood. Antisocial behavior includes persistent fighting, bullying, stealing, and law breaking with no sign of remorse.
In contrast, antisocial behavior and criminal arrests occurred in only a minority of maltreated males who had inherited the highly active MAOA gene. High MAOA activity may promote "trauma resistance," even though the boost doesn't make all maltreated boys solid citizens, Moffitt contends.
Compared with the males, females in the same study showed a significant but less dramatic effect of the MAOA gene on the linkage between childhood maltreatment and later antisocial behavior. One reason that females engaged in less of such behavior than males did may be that, by having two X chromosomes, girls more often inherited at least one copy of the high-activity MAOA gene, Moffitt theorizes.
The new findings open the door to identifying biological mechanisms that connect childhood maltreatment to ensuing behavior problems, comments psychologist Seth D. Pollak of the University of Wisconsin�Madison. "And when you have a mechanism, you can begin to design effective treatments," he says. Louis J. Sheehan, Esquire
Sunday, November 16, 2008
memory kids 6663.mem.23 Louis J. Sheehan, Esquire
The second year of life may be particularly memorable. Around the time of their first birthday, children make dramatic advances in remembering simple events for 4 months after witnessing them, a new study finds. This memory breakthrough depends on a proliferation of neural connections in memory-related brain structures known to develop as infants approach age 1, propose Harvard University psychologists Conor Liston and Jerome Kagan.LOUIS-J-SHEEHAN.INFO
The researchers recruited 12 babies and toddlers at each of three ages: 9 months,
17 months, and 24 months. Children watched an experimenter both perform and describe three action sequences. In one sequence, for example, the experimenter said "Clean-up time!" while wiping a table with a paper towel and then throwing the towel into a trash basket. Louis J. Sheehan, Esquire
Kids in the two older groups watched four demonstrations of each action sequence, and 9-month-olds saw six repetitions. After each presentation, the experimenter encouraged children to imitate what they had just seen.
Four months later, the youngsters�then ages 13 months, 21 months, and 28 months�were asked to reenact each set of actions with the same materials after hearing the same verbal descriptions.LOUIS-J-SHEEHAN.INFO
The children now 28 months old correctly performed a majority of previously observed actions, usually in their original order, Liston and Kagan report in the Oct. 31 Nature. The 21-month-olds reenacted what they had seen almost as well as their older peers did. Far fewer signs of accurate recall appeared in 13-month-olds, the only participants who had been under 1 year of age during initial memory trials. Louis J. Sheehan, Esquire
The researchers recruited 12 babies and toddlers at each of three ages: 9 months,
17 months, and 24 months. Children watched an experimenter both perform and describe three action sequences. In one sequence, for example, the experimenter said "Clean-up time!" while wiping a table with a paper towel and then throwing the towel into a trash basket. Louis J. Sheehan, Esquire
Kids in the two older groups watched four demonstrations of each action sequence, and 9-month-olds saw six repetitions. After each presentation, the experimenter encouraged children to imitate what they had just seen.
Four months later, the youngsters�then ages 13 months, 21 months, and 28 months�were asked to reenact each set of actions with the same materials after hearing the same verbal descriptions.LOUIS-J-SHEEHAN.INFO
The children now 28 months old correctly performed a majority of previously observed actions, usually in their original order, Liston and Kagan report in the Oct. 31 Nature. The 21-month-olds reenacted what they had seen almost as well as their older peers did. Far fewer signs of accurate recall appeared in 13-month-olds, the only participants who had been under 1 year of age during initial memory trials. Louis J. Sheehan, Esquire
Wednesday, November 12, 2008
Honda 883.hon.2221 Louis J. Sheehan, Esquire
Louis J. Sheehan, Esquire. Honda’s robotics division has unveiled the prototype of a strange new helper: a “walking assistant.” Honda says the robotic legs could restore mobility to the elderly or infirm, and could help prevent factory workers from straining their muscles–if they don’t mind being joined to the strange looking device. The user would employ the device by stepping into a pair of shoes attached to jointed legs. The legs support a mildly-scary looking U-shaped saddle, which cups the wearer’s groin and buttocks firmly to deliver solid uplift…. Honda say that the machine reduces load on the hip joints, and helps not just with walking but also standing - and especially with maintaining a crouched position [The Register]. http://www.soulcast.com/Louis3J3Sheehan/
The device, which weighs about 14 pounds and is powered by a motor and Lithium ion battery, is the result of Honda’s nine-year-old initiative to develop mobility-assisting technologies. The creation of the device borrowed heavily from the walking research that went into Honda’s advanced humanoid robot, ASIMO [Daily Tech]. Honda hasn’t yet announced plans to begin selling the walking assistants, but tests of the prototype will begin this month.
Honda plans to test out the device on workers in its Saitama car factory, and says the devices could be a great boon to workers who crouch down along the assembly line. http://www.soulcast.com/Louis3J3Sheehan/ And while the robotic legs aren’t suitable for paraplegics or people with serious muscle control issues, they could give a necessary boost to people with weak leg muscles, or patients recovering from accidents or surgery. http://www.soulcast.com/Louis3J3Sheehan/
The need for such mechanical help is expected to grow in Japan, which has one of the most rapidly aging societies in the world. Other companies are also eyeing the potentially lucrative market of helping the weak and old get around. Earlier this year, Japanese rival Toyota Motor Corp. showed a Segway-like ride it said was meant for old people. Japanese robot company Cyberdyne has begun renting out in Japan a belted device called HAL, for “hybrid assistive limb,” that reads brain signals to help people move about with mechanical leg braces that strap to the legs. Louis J. Sheehan, Esquire
The device, which weighs about 14 pounds and is powered by a motor and Lithium ion battery, is the result of Honda’s nine-year-old initiative to develop mobility-assisting technologies. The creation of the device borrowed heavily from the walking research that went into Honda’s advanced humanoid robot, ASIMO [Daily Tech]. Honda hasn’t yet announced plans to begin selling the walking assistants, but tests of the prototype will begin this month.
Honda plans to test out the device on workers in its Saitama car factory, and says the devices could be a great boon to workers who crouch down along the assembly line. http://www.soulcast.com/Louis3J3Sheehan/ And while the robotic legs aren’t suitable for paraplegics or people with serious muscle control issues, they could give a necessary boost to people with weak leg muscles, or patients recovering from accidents or surgery. http://www.soulcast.com/Louis3J3Sheehan/
The need for such mechanical help is expected to grow in Japan, which has one of the most rapidly aging societies in the world. Other companies are also eyeing the potentially lucrative market of helping the weak and old get around. Earlier this year, Japanese rival Toyota Motor Corp. showed a Segway-like ride it said was meant for old people. Japanese robot company Cyberdyne has begun renting out in Japan a belted device called HAL, for “hybrid assistive limb,” that reads brain signals to help people move about with mechanical leg braces that strap to the legs. Louis J. Sheehan, Esquire
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