A catastrophic event -- such as a terrorist attack, a natural disaster, or market collapse -- often strikes twice. There is the damage caused by the event itself, as lives are lost or left in ruin. But there is also the second act, catalyzed by our response to the catastrophic event. This second act has the potential to cause just as much damage as the first.
In the year following the terrorist attacks of September 11, 2001, there were approximately 1,600 more traffic fatalities in the United States than expected. This figure suggests the possibility that fear may have been a strong motivator for many people, leading them to choose driving over flying. This change in behavior, motivated by fear, may have ultimately led to additional deaths through traffic fatalities.
But fear does not tell the whole story. As Wolfgang Gaissmaier and Gerd Gigerenzer of the Harding Center for Risk Literacy at the Max Planck Institute for Human Development in Berlin, Germany, observe, the changes in driving behavior observed after 9/11 varied widely across different regions of the United States and did not just occur in those states closest to the attacks where fear was presumably strongest.
Gaissmaier and Gigerenzer hypothesized that another factor might have played a central role: driving opportunity. While fear provides a motivational explanation, in order for people to substitute driving for flying there had to be an environmental structure that allowed fear to manifest in a behavior change.
The researchers explore this hypothesis in a new research article to be published in Psychological Science, a journal of the Association for Psychological Science.
They collected data on the number of miles driven and the number of traffic fatalities per month from each of the 50 states and the District of Columbia. They also gathered data on fear and driving opportunity. They used proximity to New York City to get an approximate measure of post-9/11 fear, as previous research had shown that proximity was linked with substantial stress reactions after the attacks. To measure driving opportunity, they assessed the length of nationally significant highways in each state in the National Highway System, divided by the number of state inhabitants and they also looked at the number of car registrations per inhabitant.
The results of the analyses show that people did in fact drive more following 9/11: Across all states, the average monthly increase in miles driven per inhabitant was 27.2 miles in the three months following the attacks. This increase was significantly greater than that observed in the same three-month period in the five years leading up to 2001.
Interestingly, people who were closer to New York City showed only a slight increase in driving. Increase in miles driven was strongly associated, however, with greater driving opportunity. Most importantly, increased driving was associated with an increase in traffic fatalities. These findings suggest that fear can lead people to engage in potentially dangerous behaviors, such as increased driving, but that understanding fear is not enough.
"To be able to foresee where the secondary effects of catastrophic events could have fatal consequences, we need to look at the environmental structures that allow fear to actually manifest in dangerous behaviors."
Read more at Science Daily
Aug 31, 2012
Why Dogs Really Do Feel Your Pain
Dogs may empathize with humans more than any other animal, including humans themselves, several new studies suggest.
The latest research, published in the journal Animal Cognition, found that pet dogs may truly be man (or woman's) best friend if a person is in distress. That distressed individual does not even have to be someone the dog knows.
"I think there is good reason to suspect dogs would be more sensitive to human emotion than other species," co-author Deborah Custance told Discovery News. "We have domesticated dogs over a long period of time. We have selectively bred them to act as our companions."
"Thus," she added," those dogs that responded sensitively to our emotional cues may have been the individuals that we would be more likely to keep as pets and breed from."
Custance and colleague Jennifer Mayer, both from the Department of Psychology at the University of London Goldsmiths College, exposed 18 pet dogs -- representing different ages and breeds -- to four separate 20-second human encounters. The human participants included the dogs' owners as well as strangers.
During one experimental condition, the people hummed in a weird way. For that one, the scientists were trying to see if unusual behavior itself could trigger canine concern. The people also talked and pretended to cry.
The majority of the dogs comforted the person, owner or not, when that individual was pretending to cry. The dogs acted submissive as they nuzzled and licked the person, the canine version of "there there." Custance and Mayer say this behavior is consistent with empathic concern and the offering of comfort.
As for what could be going on in the dog's head, yet another recent study, published in PLoS ONE, showed how the brains of dogs react as the canines view humans. In this case, the researchers trained dogs to respond to hand signals that meant the pups would receive a hot dog treat. Another signal meant no such treat was coming.
The caudate region of the dogs' brains, an area associated with rewards in humans, showed activation when the canines knew a tasty food treat was coming.
"These results indicate that dogs pay very close attention to human signals," lead researcher Gregory Berns, director of the Emory Center for Neuropolicy, explained. "And these signals may have a direct line to the dog's reward system."
In that study, the reward was food, but Custance and Mayer think canines over the thousands of years of domestication have been rewarded so much for approaching distressed human companions that this may somehow be hardwired into today's dogs.
Read more at Discovery News
The latest research, published in the journal Animal Cognition, found that pet dogs may truly be man (or woman's) best friend if a person is in distress. That distressed individual does not even have to be someone the dog knows.
"I think there is good reason to suspect dogs would be more sensitive to human emotion than other species," co-author Deborah Custance told Discovery News. "We have domesticated dogs over a long period of time. We have selectively bred them to act as our companions."
"Thus," she added," those dogs that responded sensitively to our emotional cues may have been the individuals that we would be more likely to keep as pets and breed from."
Custance and colleague Jennifer Mayer, both from the Department of Psychology at the University of London Goldsmiths College, exposed 18 pet dogs -- representing different ages and breeds -- to four separate 20-second human encounters. The human participants included the dogs' owners as well as strangers.
During one experimental condition, the people hummed in a weird way. For that one, the scientists were trying to see if unusual behavior itself could trigger canine concern. The people also talked and pretended to cry.
The majority of the dogs comforted the person, owner or not, when that individual was pretending to cry. The dogs acted submissive as they nuzzled and licked the person, the canine version of "there there." Custance and Mayer say this behavior is consistent with empathic concern and the offering of comfort.
As for what could be going on in the dog's head, yet another recent study, published in PLoS ONE, showed how the brains of dogs react as the canines view humans. In this case, the researchers trained dogs to respond to hand signals that meant the pups would receive a hot dog treat. Another signal meant no such treat was coming.
The caudate region of the dogs' brains, an area associated with rewards in humans, showed activation when the canines knew a tasty food treat was coming.
"These results indicate that dogs pay very close attention to human signals," lead researcher Gregory Berns, director of the Emory Center for Neuropolicy, explained. "And these signals may have a direct line to the dog's reward system."
In that study, the reward was food, but Custance and Mayer think canines over the thousands of years of domestication have been rewarded so much for approaching distressed human companions that this may somehow be hardwired into today's dogs.
Read more at Discovery News
Two Mars Rovers Search for Clues to Life
NASA's Mars rover Curiosity isn't the only vehicle driving on the Red Planet this week. A long-lived sibling rover is closing in on what may be its most scientifically interesting target since arriving on Mars more than eight years ago.
The golf-cart sized Mars Exploration Rover Opportunity is expected to soon reach a patch of bedrock on the rim of Endeavour Crater, located on the opposite side of the planet from Curiosity's landing site. The rock is believe to contain clay minerals, which form in the presence of water.
Clays also are believed to exist in the lower layers of Mount Sharp, the three-mile high mound of sediment that rises from the floor of Gale Crater, where Curiosity touched down on Aug. 6.
The timing is ironic, and possibly fortuitous. Opportunity, along with its twin rover Spirit, were only designed for 90-day missions to determine if their landing sites showed signs of past water.
The answers from both were a resounding "yes," paving the way for the much better equipped and more robust Curiosity geochemistry robot, which just began a two-year quest to assess the planet's potential for microbial life.
"One way I like to think about it is that Opportunity is the field geologist doing the exploration type of stuff, and Curiosity is the geologist who then takes samples back to his lab to do more detailed analysis on them," planetary scientist Diana Blaney, with NASA's Jet Propulsion Laboratory in Pasadena, Calif., told Discovery News.
The different missions grew out of different, but complementary science goals.
"When Spirit and Opportunity were built, we had places (on Mars) that we knew had had water, but we really didn't have any evidence for any place where water had been around doing chemistry on the surface for a long time.
"In that era the big questions were 'What is the history of water at these particular locations on Mars?'" Blaney said.
With its 10 science instruments and a two-year design life, Curiosity, which is about the size of a small car, is intended to address two difficult follow-on questions: whether Mars had ingredients besides water, such as organics, necessary for life and whether it had the means to preserve it.
"The missions inform each other to a limited extent," said Cornell University's Steve Squyres, the lead scientist on the Opportunity mission and a participating investigator on Curiosity's.
Read more at Discovery News
The golf-cart sized Mars Exploration Rover Opportunity is expected to soon reach a patch of bedrock on the rim of Endeavour Crater, located on the opposite side of the planet from Curiosity's landing site. The rock is believe to contain clay minerals, which form in the presence of water.
Clays also are believed to exist in the lower layers of Mount Sharp, the three-mile high mound of sediment that rises from the floor of Gale Crater, where Curiosity touched down on Aug. 6.
The timing is ironic, and possibly fortuitous. Opportunity, along with its twin rover Spirit, were only designed for 90-day missions to determine if their landing sites showed signs of past water.
The answers from both were a resounding "yes," paving the way for the much better equipped and more robust Curiosity geochemistry robot, which just began a two-year quest to assess the planet's potential for microbial life.
"One way I like to think about it is that Opportunity is the field geologist doing the exploration type of stuff, and Curiosity is the geologist who then takes samples back to his lab to do more detailed analysis on them," planetary scientist Diana Blaney, with NASA's Jet Propulsion Laboratory in Pasadena, Calif., told Discovery News.
The different missions grew out of different, but complementary science goals.
"When Spirit and Opportunity were built, we had places (on Mars) that we knew had had water, but we really didn't have any evidence for any place where water had been around doing chemistry on the surface for a long time.
"In that era the big questions were 'What is the history of water at these particular locations on Mars?'" Blaney said.
With its 10 science instruments and a two-year design life, Curiosity, which is about the size of a small car, is intended to address two difficult follow-on questions: whether Mars had ingredients besides water, such as organics, necessary for life and whether it had the means to preserve it.
"The missions inform each other to a limited extent," said Cornell University's Steve Squyres, the lead scientist on the Opportunity mission and a participating investigator on Curiosity's.
Read more at Discovery News
Let It Snow, Let It Snow ... CO2
What if you could build a giant refrigeration unit near the South Pole, pulling harmful carbon dioxide out of the Earth’s atmosphere, turning it into snow and burying it underground. Wind turbines would power the chiller plants, converting CO2 from a heat-trapping atmospheric gas to a solid as a way of slowing down climate change.
Of all the greenhouse gases, CO2 is the "control knob" of climate change. There's currently too much of it in our atmosphere, and the more of it that there is, the greater the effects of warming.
It sounds far-fetched, but researchers at Purdue University have put together a plan on how such a device would work.
“It’s kind of a novel idea and it’s going to take a lot of refrigeration units and a lot of cost,” said Ernest Agee, professor earth and planetary sciences at Purdue and author of the paper appearing in the Journal of Applied Meteorology and Climatology.
Water vapor turns to snow around 32 degrees Fahrenheit, but CO2 doesn’t switch from gas to solid until it gets down to a chilly -220 degrees Fahrenheit (133 Kelvin). The ambient air temperature in Antarctica can often reach -100 F, which gives the chilling process a head start.
But to transform the planet’s atmospheric CO2 into snow, it would take an estimated 446 individual refrigeration units that use a closed-loop liquid nitrogen process. The units would be powered by 16 1,200-megawatt wind turbines. That’s a lot of power.
Agee says the idea came to him during a discussion about Mars’ south polar ice cap, which was found to consist of CO2 by the Mars Global Surveyor and Odyssey missions.
He says Antarctica’s coastline would be the best place to put the chiller plants and the turbines since the coast gets blasts of high-powered winds that cascade down from the higher South Polar ice cap toward the ocean. The CO2 snow would be stored in insulated landfills. The winds can power the turbines, while excess heat from the chillers and electricity from the turbines can be harnessed to keep Antarctic research stations warm and dry.
Russell Donnelly, a University of Oregon physicist, is intrigued with Agee’s idea.“It’s quite exciting,” Donnelly said. “It’s certainly thinking big.”
Donnelly is pushing his own, slightly different idea of chilling carbon dioxide. He wants to install chillers at coal-burning power plants to remove C02 from smokestacks.
“You look at the hot gases of a stack, it would look impossible,” Donnelly said. “But you can cool them off with water sprays and down to room temperature without spending much money. Then if you start to refrigerate, you need to put just enough refrigeration to get the job done.”
Donnelly and colleagues published a paper in the July 12 issue of the journal Physical Review E that spells out how he would build such a device.
He said the electricity would cost 25 percent more to produce, “but you would have an environmentally-friendly power plant.”
Read more at Discovery News
Of all the greenhouse gases, CO2 is the "control knob" of climate change. There's currently too much of it in our atmosphere, and the more of it that there is, the greater the effects of warming.
It sounds far-fetched, but researchers at Purdue University have put together a plan on how such a device would work.
“It’s kind of a novel idea and it’s going to take a lot of refrigeration units and a lot of cost,” said Ernest Agee, professor earth and planetary sciences at Purdue and author of the paper appearing in the Journal of Applied Meteorology and Climatology.
Water vapor turns to snow around 32 degrees Fahrenheit, but CO2 doesn’t switch from gas to solid until it gets down to a chilly -220 degrees Fahrenheit (133 Kelvin). The ambient air temperature in Antarctica can often reach -100 F, which gives the chilling process a head start.
But to transform the planet’s atmospheric CO2 into snow, it would take an estimated 446 individual refrigeration units that use a closed-loop liquid nitrogen process. The units would be powered by 16 1,200-megawatt wind turbines. That’s a lot of power.
Agee says the idea came to him during a discussion about Mars’ south polar ice cap, which was found to consist of CO2 by the Mars Global Surveyor and Odyssey missions.
He says Antarctica’s coastline would be the best place to put the chiller plants and the turbines since the coast gets blasts of high-powered winds that cascade down from the higher South Polar ice cap toward the ocean. The CO2 snow would be stored in insulated landfills. The winds can power the turbines, while excess heat from the chillers and electricity from the turbines can be harnessed to keep Antarctic research stations warm and dry.
Russell Donnelly, a University of Oregon physicist, is intrigued with Agee’s idea.“It’s quite exciting,” Donnelly said. “It’s certainly thinking big.”
Donnelly is pushing his own, slightly different idea of chilling carbon dioxide. He wants to install chillers at coal-burning power plants to remove C02 from smokestacks.
“You look at the hot gases of a stack, it would look impossible,” Donnelly said. “But you can cool them off with water sprays and down to room temperature without spending much money. Then if you start to refrigerate, you need to put just enough refrigeration to get the job done.”
Donnelly and colleagues published a paper in the July 12 issue of the journal Physical Review E that spells out how he would build such a device.
He said the electricity would cost 25 percent more to produce, “but you would have an environmentally-friendly power plant.”
Read more at Discovery News
Aug 30, 2012
Surprisingly Bright Superbubble in Nearby Nebula
A new composite image shows a superbubble in the Large Magellanic Cloud (LMC), a small satellite galaxy of the Milky Way, located about 160,000 light years from Earth. Many new stars, some of them very massive, are forming in the star cluster NGC 1929, which is embedded in the nebula N44.
The massive stars produce intense radiation, expel matter at high speeds, and race through their evolution to explode as supernovas. The winds and supernova shock waves carve out huge cavities called superbubbles in the surrounding gas. X-rays from NASA's Chandra X-ray Observatory (blue) show hot regions created by these winds and shocks, while infrared data from NASA's Spitzer Space Telescope (red) outline where the dust and cooler gas are found. The optical light from the 2.2m Max-Planck-ESO telescope (yellow) in Chile shows where ultraviolet radiation from hot, young stars is causing gas in the nebula to glow.
A long-running problem in high-energy astrophysics has been that some superbubbles in the LMC, including N44, give off a lot more X-rays than expected from models of their structure. A Chandra study published in 2011 showed that there are two extra sources of the bright X-ray emission: supernova shock waves striking the walls of the cavities, and hot material evaporating from the cavity walls. The observations show no evidence for an enhancement of elements heavier than hydrogen and helium in the cavities, thus ruling out this possibility as an explanation for the bright X-ray emission. T
his is the first time that the data have been good enough to distinguish between different sources of the X-rays produced by superbubbles.
Read more at Science Daily
The massive stars produce intense radiation, expel matter at high speeds, and race through their evolution to explode as supernovas. The winds and supernova shock waves carve out huge cavities called superbubbles in the surrounding gas. X-rays from NASA's Chandra X-ray Observatory (blue) show hot regions created by these winds and shocks, while infrared data from NASA's Spitzer Space Telescope (red) outline where the dust and cooler gas are found. The optical light from the 2.2m Max-Planck-ESO telescope (yellow) in Chile shows where ultraviolet radiation from hot, young stars is causing gas in the nebula to glow.
A long-running problem in high-energy astrophysics has been that some superbubbles in the LMC, including N44, give off a lot more X-rays than expected from models of their structure. A Chandra study published in 2011 showed that there are two extra sources of the bright X-ray emission: supernova shock waves striking the walls of the cavities, and hot material evaporating from the cavity walls. The observations show no evidence for an enhancement of elements heavier than hydrogen and helium in the cavities, thus ruling out this possibility as an explanation for the bright X-ray emission. T
his is the first time that the data have been good enough to distinguish between different sources of the X-rays produced by superbubbles.
Read more at Science Daily
Extinct Human Genome Reveals Brown-Eyed Girl
The genome of a recently discovered branch of extinct humans known as the Denisovans that once interbred with us has been sequenced, scientists said today.
Genetic analysis of the fossil revealed it apparently belonged to a little girl with dark skin, brown hair and brown eyes, researchers said. All in all, the scientists discovered about 100,000 recent changes in our genome that occurred after the split from the Denisovans. A number of these changes influence genes linked with brain function and nervous system development, leading to speculation that we may think differently from the Denisovans. Other changes are linked with the skin, eyes and teeth.
"This research will help [in] determining how it was that modern human populations came to expand dramatically in size as well as cultural complexity, while archaic humans eventually dwindled in numbers and became physically extinct," said researcher Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Future research may turn up other groups of extinct humans in Asia "in addition to Neanderthals and Denisovans," Pääbo told LiveScience.
Although our species comprises the only humans left alive, our planet was once home to a variety of other human species. The Neanderthals were apparently our closest relatives, and the last of the other human lineages to vanish.
However, scientists recently revealed another group of extinct humans once lived at the same time as ours. DNA from fossils unearthed in Denisova Cave in southern Siberia in 2008 revealed a lineage unlike us and closely related to Neanderthals. The precise age of the Denisovan material remains uncertain — anywhere from 30,000 to 80,000 years of age.
"The Denisovan genome is particularly close to my heart, because it was the first time that a new group of extinct humans was discovered and defined just from DNA sequence evidence and not from the morphology of bones," Pääbo said.
Denisovan genes unzipped
Now, based on only a tiny sample of genetic material from a finger bone, scientists have sequenced the complete genome of the Denisovans (pronounced deh-NEESE-so-vans), as they are now called.
To make the most of what little genetic material they had, the researchers developed a technique that unzipped the double strands of DNA in the bone, doubling the amount of DNA they could analyze. This enabled them to sequence each position in the genome about 30 times over, generating an extremely thorough genome sequence.
"We have very few errors in the sequences, even less errors than we often have when you sequence a person today," Pääbo said. "With just a few technical reservations, there is actually today then no difference in what we can learn genetically about a person that lived 50,000 years ago and from a person today, provided that we have well-enough preserved bones."
Comparing the Denisovan genome with ours confirmed past research suggesting the extinct lineage once interbred with ours and lived in a vast range from Siberia to Southeast Asia. The Denisovans share more genes with people from Papua New Guinea than any other modern population studied.
In addition, more Denisovan genetic variants were found in Asia and South America than in European populations. However, this likely reflects interbreeding between modern humans and the Denisovans' close relatives, the Neanderthals, rather than direct interbreeding with the Denisovans, researchers said.
Denisovans began to diverge from modern humans in terms of DNA sequences about 800,000 years ago. Among the genetic differences between Denisovans and modern humans are likely changes that "are essential for what made modern human history possible, the very rapid development of human technology and culture that allowed our species to become so numerous, spread around the whole world, and actually dominate large parts of the biosphere," Pääbo said.
Eight of these genetic changes have to do with brain function and brain development, "the connectivity in the brain of synapses between nerve cells function, and some of them have to do with genes that, for example, can cause autism when these genes are mutated," Pääbo added.
What makes humans special?
It makes a lot of sense to speculate that what makes us special in the world relative to the Denisovans and Neanderthals "is about connectivity in the brain," Pääbo said. "Neanderthals had just as large brains as modern humans had — relative to body size, they even had a bit larger brains. Yet there is, of course, something special in my mind that happens with modern humans. It's sort of this extremely rapid technological cultural development that comes, large societal systems, and so on. So it makes sense that, well, what pops up is sort of connectivity in the brain."
The fact that differences are seen between modern humans and Denisovans in terms of autism-linked genes is especially interesting, because whole books have been written "suggesting that autism may affect sort of a trait in human cognition that is also crucial for modern humans, for how we put ourselves in the shoes of others, manipulate others, lie, develop politics and big societies and so on," Pääbo said.
The genetic diversity suggested by this Denisovan sample was apparently quite low. This was probably not due to inbreeding, the researchers say — rather, their vast range suggests their population was initially quite small but grew quickly, without time for genetic diversity to increase as well.
"If future research of the Neanderthal genome shows that their population size changed over time in similar ways, it may well be that a single population expanding out of Africa gave rise to both the Denisovans and the Neanderthals," Pääbo said.
Intriguingly, comparing the X chromosome, which is passed down by females, to the rest of the genome, which is passed down equally in males and females, revealed "there is substantially less Denisovan genetic material in New Guinea on the X chromosome than there is on the rest of the genome,"researcher David Reich at Harvard Medical School in Boston told LiveScience.
One possible explanation "is that the Denisovan gene flow into modern humans was mediated primarily by male Denisovans mixing with female modern humans," Reich said. "Another possible explanation is that actually there was natural selection to remove genetic material on the X chromosome that came from Denisovans once that entered the modern human population, perhaps because it caused problems for the people who carried it."
Read more at Discovery News
Genetic analysis of the fossil revealed it apparently belonged to a little girl with dark skin, brown hair and brown eyes, researchers said. All in all, the scientists discovered about 100,000 recent changes in our genome that occurred after the split from the Denisovans. A number of these changes influence genes linked with brain function and nervous system development, leading to speculation that we may think differently from the Denisovans. Other changes are linked with the skin, eyes and teeth.
"This research will help [in] determining how it was that modern human populations came to expand dramatically in size as well as cultural complexity, while archaic humans eventually dwindled in numbers and became physically extinct," said researcher Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Future research may turn up other groups of extinct humans in Asia "in addition to Neanderthals and Denisovans," Pääbo told LiveScience.
Although our species comprises the only humans left alive, our planet was once home to a variety of other human species. The Neanderthals were apparently our closest relatives, and the last of the other human lineages to vanish.
However, scientists recently revealed another group of extinct humans once lived at the same time as ours. DNA from fossils unearthed in Denisova Cave in southern Siberia in 2008 revealed a lineage unlike us and closely related to Neanderthals. The precise age of the Denisovan material remains uncertain — anywhere from 30,000 to 80,000 years of age.
"The Denisovan genome is particularly close to my heart, because it was the first time that a new group of extinct humans was discovered and defined just from DNA sequence evidence and not from the morphology of bones," Pääbo said.
Denisovan genes unzipped
Now, based on only a tiny sample of genetic material from a finger bone, scientists have sequenced the complete genome of the Denisovans (pronounced deh-NEESE-so-vans), as they are now called.
To make the most of what little genetic material they had, the researchers developed a technique that unzipped the double strands of DNA in the bone, doubling the amount of DNA they could analyze. This enabled them to sequence each position in the genome about 30 times over, generating an extremely thorough genome sequence.
"We have very few errors in the sequences, even less errors than we often have when you sequence a person today," Pääbo said. "With just a few technical reservations, there is actually today then no difference in what we can learn genetically about a person that lived 50,000 years ago and from a person today, provided that we have well-enough preserved bones."
Comparing the Denisovan genome with ours confirmed past research suggesting the extinct lineage once interbred with ours and lived in a vast range from Siberia to Southeast Asia. The Denisovans share more genes with people from Papua New Guinea than any other modern population studied.
In addition, more Denisovan genetic variants were found in Asia and South America than in European populations. However, this likely reflects interbreeding between modern humans and the Denisovans' close relatives, the Neanderthals, rather than direct interbreeding with the Denisovans, researchers said.
Denisovans began to diverge from modern humans in terms of DNA sequences about 800,000 years ago. Among the genetic differences between Denisovans and modern humans are likely changes that "are essential for what made modern human history possible, the very rapid development of human technology and culture that allowed our species to become so numerous, spread around the whole world, and actually dominate large parts of the biosphere," Pääbo said.
Eight of these genetic changes have to do with brain function and brain development, "the connectivity in the brain of synapses between nerve cells function, and some of them have to do with genes that, for example, can cause autism when these genes are mutated," Pääbo added.
What makes humans special?
It makes a lot of sense to speculate that what makes us special in the world relative to the Denisovans and Neanderthals "is about connectivity in the brain," Pääbo said. "Neanderthals had just as large brains as modern humans had — relative to body size, they even had a bit larger brains. Yet there is, of course, something special in my mind that happens with modern humans. It's sort of this extremely rapid technological cultural development that comes, large societal systems, and so on. So it makes sense that, well, what pops up is sort of connectivity in the brain."
The fact that differences are seen between modern humans and Denisovans in terms of autism-linked genes is especially interesting, because whole books have been written "suggesting that autism may affect sort of a trait in human cognition that is also crucial for modern humans, for how we put ourselves in the shoes of others, manipulate others, lie, develop politics and big societies and so on," Pääbo said.
The genetic diversity suggested by this Denisovan sample was apparently quite low. This was probably not due to inbreeding, the researchers say — rather, their vast range suggests their population was initially quite small but grew quickly, without time for genetic diversity to increase as well.
"If future research of the Neanderthal genome shows that their population size changed over time in similar ways, it may well be that a single population expanding out of Africa gave rise to both the Denisovans and the Neanderthals," Pääbo said.
Intriguingly, comparing the X chromosome, which is passed down by females, to the rest of the genome, which is passed down equally in males and females, revealed "there is substantially less Denisovan genetic material in New Guinea on the X chromosome than there is on the rest of the genome,"researcher David Reich at Harvard Medical School in Boston told LiveScience.
One possible explanation "is that the Denisovan gene flow into modern humans was mediated primarily by male Denisovans mixing with female modern humans," Reich said. "Another possible explanation is that actually there was natural selection to remove genetic material on the X chromosome that came from Denisovans once that entered the modern human population, perhaps because it caused problems for the people who carried it."
Read more at Discovery News
Stone Age Figurines Found Near Jerusalem
Two Stone Age statuettes, one depicting a ram and the other a wild bovine, have emerged from the highway connecting Jerusalem with Tel Aviv.
Found at Tel Moza, a couple miles north of Jerusalem, during a dig ahead of the widening of Highway 1, the 5.9-inch-long figurines are estimated to date between 9,000 and 9,500 years ago.
The first figurine, shaped in the image of a ram, is made of limestone and features intricately carved horns.
"The sculpting is extraordinary and precisely depicts details of the animal's image; the head and the horns protrude in front of the body and their proportions are extremely accurate," Anna Eirikh and Hamoudi Khalaily, directors of the excavation on behalf of the Israel Antiquities Authority (IAA), said in a statement.
"The legs of the figurine were incised in order to distinguish them from the rest of the body," they added.
The second figurine, fashioned on hard smoothed dolomite, is an abstract design. According to the archaeologists, it appears to depict a large animal with prominent horns that separate the elongated body from the head.
"The horns emerge from the middle of the head sideward and resemble those of a wild bovine or buffalo," the archaeologists said.
Discovered near a round building whose foundation was made of fieldstone and mud brick, the statuettes might help shed light on religion and society during the New Stone Age, or Pre-Pottery Neolithic B period about 8,000 BC.
At that time humans began transitioning from nomadism, based on hunting and gathering, to sedentary life, based on farming and grazing.
One theory is that the statuettes were used as talismans.
"It is known that hunting was the major activity in this period. Presumably, the figurines served as good-luck statues for ensuring the success of the hunt," Khalaily said.
"They might have been the focus of a traditional ceremony the hunters performed before going out into the field to pursue their prey," he said.
Read more at Discovery News
Found at Tel Moza, a couple miles north of Jerusalem, during a dig ahead of the widening of Highway 1, the 5.9-inch-long figurines are estimated to date between 9,000 and 9,500 years ago.
The first figurine, shaped in the image of a ram, is made of limestone and features intricately carved horns.
"The sculpting is extraordinary and precisely depicts details of the animal's image; the head and the horns protrude in front of the body and their proportions are extremely accurate," Anna Eirikh and Hamoudi Khalaily, directors of the excavation on behalf of the Israel Antiquities Authority (IAA), said in a statement.
"The legs of the figurine were incised in order to distinguish them from the rest of the body," they added.
The second figurine, fashioned on hard smoothed dolomite, is an abstract design. According to the archaeologists, it appears to depict a large animal with prominent horns that separate the elongated body from the head.
"The horns emerge from the middle of the head sideward and resemble those of a wild bovine or buffalo," the archaeologists said.
Discovered near a round building whose foundation was made of fieldstone and mud brick, the statuettes might help shed light on religion and society during the New Stone Age, or Pre-Pottery Neolithic B period about 8,000 BC.
At that time humans began transitioning from nomadism, based on hunting and gathering, to sedentary life, based on farming and grazing.
One theory is that the statuettes were used as talismans.
"It is known that hunting was the major activity in this period. Presumably, the figurines served as good-luck statues for ensuring the success of the hunt," Khalaily said.
"They might have been the focus of a traditional ceremony the hunters performed before going out into the field to pursue their prey," he said.
Read more at Discovery News
WISE Discovers Galactic Hot DOGs
When NASA launched a wide-field, infrared telescope named WISE to survey the cosmos, scientists figured it would unearth some new objects. They didn't, however, expect to find a whole new type of galaxy.
WISE scientists are calling their find "hot DOG," for hot, Dust-Obscured Galaxy, which is an apt description, considering the galaxies are twice as hot as similar objects and difficult to find since most of their radiation is blocked by shrouds of dust.
But WISE ferreted out about 1,000 hot DOGS, each of which can put out more than 1,000 times the energy of the Milky Way, thus earning themselves top billing on the list of most luminous objects in the universe.
In astronomical numbers, 1,000 is tiny, accounting for about 1-in-100,000 light sources, scientists said during a conference call with reporters on Wednesday.
About 70 percent of the hot DOGS are 10 billion light-years away, meaning they formed when the universe was quite young. (The most precise measurement for the age of the universe is 13.75 billion years.)
Scientists aren't sure if conditions were more suited for forming hot DOGS then, or if they are just a relatively quick phase in a galaxy's life and could exist in the modern universe as well.
The objects, however, are raising new questions about the relationship between black holes and their host galaxies. Hot DOGs seem to be far brighter than what their stars can account for, leading some astronomers to suspect that a super-active, supermassive black hole may have preceded the galaxy's formation.
Black holes are regions of space so dense with matter than not even photons of light can escape the grip of gravity. They can be detected as they consume nearby matter. The majority of galaxies are believed to contain a black hole, though some, like the one at the center of our Milky Way galaxy, are relatively quiet.
Read more at Discovery News
WISE scientists are calling their find "hot DOG," for hot, Dust-Obscured Galaxy, which is an apt description, considering the galaxies are twice as hot as similar objects and difficult to find since most of their radiation is blocked by shrouds of dust.
But WISE ferreted out about 1,000 hot DOGS, each of which can put out more than 1,000 times the energy of the Milky Way, thus earning themselves top billing on the list of most luminous objects in the universe.
In astronomical numbers, 1,000 is tiny, accounting for about 1-in-100,000 light sources, scientists said during a conference call with reporters on Wednesday.
About 70 percent of the hot DOGS are 10 billion light-years away, meaning they formed when the universe was quite young. (The most precise measurement for the age of the universe is 13.75 billion years.)
Scientists aren't sure if conditions were more suited for forming hot DOGS then, or if they are just a relatively quick phase in a galaxy's life and could exist in the modern universe as well.
The objects, however, are raising new questions about the relationship between black holes and their host galaxies. Hot DOGs seem to be far brighter than what their stars can account for, leading some astronomers to suspect that a super-active, supermassive black hole may have preceded the galaxy's formation.
Black holes are regions of space so dense with matter than not even photons of light can escape the grip of gravity. They can be detected as they consume nearby matter. The majority of galaxies are believed to contain a black hole, though some, like the one at the center of our Milky Way galaxy, are relatively quiet.
Read more at Discovery News
Aug 29, 2012
Building Blocks of Life Found Around Young Star
A team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) has spotted sugar molecules in the gas surrounding a young Sun-like star. This is the first time sugar been found in space around such a star, and the discovery shows that the building blocks of life are in the right place, at the right time, to be included in planets forming around the star.
The astronomers found molecules of glycolaldehyde -- a simple form of sugar [1] -- in the gas surrounding a young binary star, with similar mass to the Sun, called IRAS 16293-2422. Glycolaldehyde has been seen in interstellar space before [2], but this is the first time it has been found so near to a Sun-like star, at distances comparable to the distance of Uranus from the Sun in the Solar System. This discovery shows that some of the chemical compounds needed for life existed in this system at the time of planet formation [3].
"In the disc of gas and dust surrounding this newly formed star, we found glycolaldehyde, which is a simple form of sugar, not much different to the sugar we put in coffee," explains Jes Jørgensen (Niels Bohr Institute, Denmark), the lead author of the paper. "This molecule is one of the ingredients in the formation of RNA, which -- like DNA, to which it is related -- is one of the building blocks of life."
The high sensitivity of ALMA -- even at the technically challenging shortest wavelengths at which it operates -- was critical for these observations, which were made with a partial array of antennas during the observatory's Science Verification phase [4].
"What it is really exciting about our findings is that the ALMA observations reveal that the sugar molecules are falling in towards one of the stars of the system," says team member Cecile Favre (Aarhus University, Denmark). "The sugar molecules are not only in the right place to find their way onto a planet, but they are also going in the right direction."
The gas and dust clouds that collapse to form new stars are extremely cold [5] and many gases solidify as ice on the particles of dust where they then bond together and form more complex molecules. But once a star has been formed in the middle of a rotating cloud of gas and dust, it heats the inner parts of the cloud to around room temperature, evaporating the chemically complex molecules, and forming gases that emit their characteristic radiation as radio waves that can be mapped using powerful radio telescopes such as ALMA.
IRAS 16293-2422 is located around 400 light-years away, comparatively close to Earth, which makes it an excellent target for astronomers studying the molecules and chemistry around young stars. By harnessing the power of a new generation of telescopes such as ALMA, astronomers now have the opportunity to study fine details within the gas and dust clouds that are forming planetary systems.
Read more at Science Daily
The astronomers found molecules of glycolaldehyde -- a simple form of sugar [1] -- in the gas surrounding a young binary star, with similar mass to the Sun, called IRAS 16293-2422. Glycolaldehyde has been seen in interstellar space before [2], but this is the first time it has been found so near to a Sun-like star, at distances comparable to the distance of Uranus from the Sun in the Solar System. This discovery shows that some of the chemical compounds needed for life existed in this system at the time of planet formation [3].
"In the disc of gas and dust surrounding this newly formed star, we found glycolaldehyde, which is a simple form of sugar, not much different to the sugar we put in coffee," explains Jes Jørgensen (Niels Bohr Institute, Denmark), the lead author of the paper. "This molecule is one of the ingredients in the formation of RNA, which -- like DNA, to which it is related -- is one of the building blocks of life."
The high sensitivity of ALMA -- even at the technically challenging shortest wavelengths at which it operates -- was critical for these observations, which were made with a partial array of antennas during the observatory's Science Verification phase [4].
"What it is really exciting about our findings is that the ALMA observations reveal that the sugar molecules are falling in towards one of the stars of the system," says team member Cecile Favre (Aarhus University, Denmark). "The sugar molecules are not only in the right place to find their way onto a planet, but they are also going in the right direction."
The gas and dust clouds that collapse to form new stars are extremely cold [5] and many gases solidify as ice on the particles of dust where they then bond together and form more complex molecules. But once a star has been formed in the middle of a rotating cloud of gas and dust, it heats the inner parts of the cloud to around room temperature, evaporating the chemically complex molecules, and forming gases that emit their characteristic radiation as radio waves that can be mapped using powerful radio telescopes such as ALMA.
IRAS 16293-2422 is located around 400 light-years away, comparatively close to Earth, which makes it an excellent target for astronomers studying the molecules and chemistry around young stars. By harnessing the power of a new generation of telescopes such as ALMA, astronomers now have the opportunity to study fine details within the gas and dust clouds that are forming planetary systems.
Read more at Science Daily
Warning On Deterioration of Famous Swedish Warship, Vasa
The famous warship, Vasa, displayed in a museum that gets 1.2 million visitors every year and ranks as one of Sweden's most popular tourist attractions, is deteriorating despite ongoing preservation efforts, scientists are reporting. Their study, citing a "significant" loss of strength in the ship's wood, appears in ACS' journal Biomacromolecules.
Ingela Bjurhager, Lars A. Berglund and colleagues explain that the Vasa sunk in the Stockholm harbor in 1628 on its maiden voyage after sailing less than a nautical mile. The ship was rediscovered in 1958, raised in 1961, treated with preservatives and finally put on display in the Vasa museum in 1990. The museum preserved the ship with polyethylene glycol (PEG) in a thick, wax-like preparation dissolved in water and sprayed onto the wood for 17 years. Concerns about deterioration arose, and the authors set out to determine the effects of PEG, iron from nails and rivets, and sulfur from decaying bacteria on the wood's strength.
The team analyzed the strength of wood taken from various locations in the ship's hull, which is largely made of oak. They report that at its worst, the wood had weakened as much as 80 percent. They suggest the loss of strength may be a result of letting the ship dry out after its recovery, allowing oxygen to react with the iron in the wood. Although they don't foresee an immediate danger to the ship, a clear understanding of the cause of the wood's degradation will be critical to preserving it for future generations. In parallel, an improved support structure is needed to minimize the stresses and deformations in the wooden hull.
Read more at Science Daily
Ingela Bjurhager, Lars A. Berglund and colleagues explain that the Vasa sunk in the Stockholm harbor in 1628 on its maiden voyage after sailing less than a nautical mile. The ship was rediscovered in 1958, raised in 1961, treated with preservatives and finally put on display in the Vasa museum in 1990. The museum preserved the ship with polyethylene glycol (PEG) in a thick, wax-like preparation dissolved in water and sprayed onto the wood for 17 years. Concerns about deterioration arose, and the authors set out to determine the effects of PEG, iron from nails and rivets, and sulfur from decaying bacteria on the wood's strength.
The team analyzed the strength of wood taken from various locations in the ship's hull, which is largely made of oak. They report that at its worst, the wood had weakened as much as 80 percent. They suggest the loss of strength may be a result of letting the ship dry out after its recovery, allowing oxygen to react with the iron in the wood. Although they don't foresee an immediate danger to the ship, a clear understanding of the cause of the wood's degradation will be critical to preserving it for future generations. In parallel, an improved support structure is needed to minimize the stresses and deformations in the wooden hull.
Read more at Science Daily
Eyeless Australian Fish Have Closest Relatives in Madagascar
A team of researchers from Louisiana State University and the American Museum of Natural History has discovered that two groups of blind cave fishes on opposite sides of the Indian Ocean are each other's closest relatives. Through comprehensive DNA analysis, the researchers determined that these eyeless fishes, one group from Madagascar and the other from similar subterranean habitats in Australia, descended from a common ancestor before being separated by continental drift nearly 100 million years ago. Their study, which appears in the journal PLoS ONE this week, also identifies new species that add to existing biological evidence for the existence of Gondwana, a prehistoric supercontinent that was part of Pangaea and contained all of today's southern continents.
"This is the first time that a taxonomically robust study has shown that blind cave vertebrates on either side of an ocean are each other's closest relatives," said Prosanta Chakrabarty, an assistant professor and curator of fishes at Louisiana State University's Museum of Natural Science. "This is a great example of biology informing geology. Often, that's how things work. These animals have no eyes and live in isolated freshwater caves, so it is highly unlikely they could have crossed oceans to inhabit new environments."
The cave fishes, of the genus Typhleotris in Madagascar and Milyeringa in Australia, are small -- less than 100 millimeters long -- and usually lack pigment, a substance that gives an organism its color and also provides protection from the sun's ultraviolet radiation. These characteristics, coupled with a lack of eyes and enhanced sensory capabilities, allow cave fishes to survive in complete darkness. For this reason, the fishes have very restricted distributions within isolated limestone caves. It's also why the newfound genetic relationship between the trans-oceanic groups is an exciting geological find.
"The sister-group relationship between cavefishes from Madagascar and Australia is a remarkable example of Gondwanan vicariance -- a geographical split dating back to the Late Cretaceous some 100 million years ago," said John Sparks, a curator in the Division of Vertebrate Zoology at the American Museum of Natural History. "The interesting thing about Madagascar's extant freshwater fish groups, with the exception of a single species, is that all exhibit relationship patterns that are in time with the Mesozoic breakup of Gondwana -- some are related to groups in India/Sri Lanka, and others to groups in Australia. Only a single freshwater species has its closest relative in nearby Africa."
One of the new species discovered by the researchers, which will be named in a future publication, is a novelty among cave fishes because it is fully and darkly pigmented. The analysis the researchers conducted for this fish's tree of life shows that it evolved from a pigment-free ancestor, indicating that some subterranean forms can "reverse" themselves for this character.
"It is generally thought that cave organisms are unable to evolve to live in other environments," Sparks said. "Our results, and the fact that we have recently discovered new cave fish species in both Madagascar and Australia belonging to these genera, are intriguing from another perspective: they show that caves are not so-called 'evolutionary dead ends.'"
Funding for the research expedition was provided by the Constantine S. Niarchos Expedition Fund, established by the Stavros Niarchos Foundation to support the research of museum curators around the globe. This particular expedition turned into more of an adventure than the group was planning -- in fact, one of the new species has been given a moniker that means "big sickness" in Malagasy because of the dangers the team incurred while searching for specimens in this dry, inhospitable region of Madagascar.
"Only two specimens of the new pigmented form were recovered from the first cave we searched in Madagascar, despite the fact that we spent hours in this sinkhole," said Chakrabarty. "Even the locals hadn't been inside of it before."
Because remote locales with caving opportunities exist all over the world, the researchers are eager to pursue other opportunities for discovery.
Read more at Science Daily
"This is the first time that a taxonomically robust study has shown that blind cave vertebrates on either side of an ocean are each other's closest relatives," said Prosanta Chakrabarty, an assistant professor and curator of fishes at Louisiana State University's Museum of Natural Science. "This is a great example of biology informing geology. Often, that's how things work. These animals have no eyes and live in isolated freshwater caves, so it is highly unlikely they could have crossed oceans to inhabit new environments."
The cave fishes, of the genus Typhleotris in Madagascar and Milyeringa in Australia, are small -- less than 100 millimeters long -- and usually lack pigment, a substance that gives an organism its color and also provides protection from the sun's ultraviolet radiation. These characteristics, coupled with a lack of eyes and enhanced sensory capabilities, allow cave fishes to survive in complete darkness. For this reason, the fishes have very restricted distributions within isolated limestone caves. It's also why the newfound genetic relationship between the trans-oceanic groups is an exciting geological find.
"The sister-group relationship between cavefishes from Madagascar and Australia is a remarkable example of Gondwanan vicariance -- a geographical split dating back to the Late Cretaceous some 100 million years ago," said John Sparks, a curator in the Division of Vertebrate Zoology at the American Museum of Natural History. "The interesting thing about Madagascar's extant freshwater fish groups, with the exception of a single species, is that all exhibit relationship patterns that are in time with the Mesozoic breakup of Gondwana -- some are related to groups in India/Sri Lanka, and others to groups in Australia. Only a single freshwater species has its closest relative in nearby Africa."
One of the new species discovered by the researchers, which will be named in a future publication, is a novelty among cave fishes because it is fully and darkly pigmented. The analysis the researchers conducted for this fish's tree of life shows that it evolved from a pigment-free ancestor, indicating that some subterranean forms can "reverse" themselves for this character.
"It is generally thought that cave organisms are unable to evolve to live in other environments," Sparks said. "Our results, and the fact that we have recently discovered new cave fish species in both Madagascar and Australia belonging to these genera, are intriguing from another perspective: they show that caves are not so-called 'evolutionary dead ends.'"
Funding for the research expedition was provided by the Constantine S. Niarchos Expedition Fund, established by the Stavros Niarchos Foundation to support the research of museum curators around the globe. This particular expedition turned into more of an adventure than the group was planning -- in fact, one of the new species has been given a moniker that means "big sickness" in Malagasy because of the dangers the team incurred while searching for specimens in this dry, inhospitable region of Madagascar.
"Only two specimens of the new pigmented form were recovered from the first cave we searched in Madagascar, despite the fact that we spent hours in this sinkhole," said Chakrabarty. "Even the locals hadn't been inside of it before."
Because remote locales with caving opportunities exist all over the world, the researchers are eager to pursue other opportunities for discovery.
Read more at Science Daily
Astronomers Discover Millions of New Black Holes and a Rare Type of Galaxy
NASA’s Wide-field Infrared Survey Telescope (WISE) has uncovered millions of supermassive black holes in our universe as well as a strange new type of galaxy, called a hot DOG or dust-obscured galaxy.
“This is a jackpot of black holes, two to three times more than have been found by any other survey,” said astronomer Daniel Stern, during a NASA press conference today.
By carefully scanning the entire night sky in infrared wavelengths, WISE has spotted more than 2.5 million black holes, all of them actively feeding on gas and dust in their host galaxies. Most of these supermassive objects, known as quasars, are roughly 10 billion light-years away.
The most energetic galaxies, the so-called hot DOGs, can pour out more than 100 trillion times the light of our sun. But they are also obscured by a massive halo of dust, which makes them imperceptible in visible wavelengths. WISE’s infrared eyes can peer through the obscuring dust though and determine the hot DOGs’ details. They are exceedingly rare, and WISE has only found about 1,000 of these objects.
The strange hot DOGs may be a key to figuring out galactic evolution in the universe. Despite nearly a century of observations, how galaxies grow and change over time is hot area of research.
Astronomers classify three types of galaxies, two of which are spirals and ellipticals. Spiral galaxies, like our Milky Way, are dominated by a flat disk with stars spinning around the center like planets orbiting a sun. They contain cold gas that can collapse and form young stars. Ellipticals, on the other hand, are full of older stars that swarm around in randomly oriented orbits, like bees buzzing around a hive.
Astronomers think that when two spiral galaxies collide, their dust and stars get scrambled around, suppressing the formation of new stars. Because of the chaotic swirling, this enormous flurry of activity could become hidden behind a layer of gas and dust, forming an object like the hot DOGs that WISE has observed.
Read more at Wired Science
“This is a jackpot of black holes, two to three times more than have been found by any other survey,” said astronomer Daniel Stern, during a NASA press conference today.
By carefully scanning the entire night sky in infrared wavelengths, WISE has spotted more than 2.5 million black holes, all of them actively feeding on gas and dust in their host galaxies. Most of these supermassive objects, known as quasars, are roughly 10 billion light-years away.
The most energetic galaxies, the so-called hot DOGs, can pour out more than 100 trillion times the light of our sun. But they are also obscured by a massive halo of dust, which makes them imperceptible in visible wavelengths. WISE’s infrared eyes can peer through the obscuring dust though and determine the hot DOGs’ details. They are exceedingly rare, and WISE has only found about 1,000 of these objects.
The strange hot DOGs may be a key to figuring out galactic evolution in the universe. Despite nearly a century of observations, how galaxies grow and change over time is hot area of research.
Astronomers classify three types of galaxies, two of which are spirals and ellipticals. Spiral galaxies, like our Milky Way, are dominated by a flat disk with stars spinning around the center like planets orbiting a sun. They contain cold gas that can collapse and form young stars. Ellipticals, on the other hand, are full of older stars that swarm around in randomly oriented orbits, like bees buzzing around a hive.
Astronomers think that when two spiral galaxies collide, their dust and stars get scrambled around, suppressing the formation of new stars. Because of the chaotic swirling, this enormous flurry of activity could become hidden behind a layer of gas and dust, forming an object like the hot DOGs that WISE has observed.
Read more at Wired Science
Flesh Eating Gulls Devour Whales Alive
Right whales (Eubalaena australis) off the coast of Argentina face the gruesome threat of being slowly eaten alive by birds every time they take a breath. The menace has become so great that local officials are planning to declare open season on the gulls and allow hunters to knock problem birds out of the sky, reported the AP.
The macabre torment of the whales sounds like a punishment from vengeful gods in a Greek myth or the plot of a Edgar Allan Poe story, but the real reason gulls have turned on the whales may be a bunch of garbage. Open air trash heaps near coastal cities have fueled a massive population boom in gulls. Fishermen add to the problem when they throw fish parts back into the ocean.
About eight years ago, the burgeoning gull population around the city of Puerto Madryn learned that they can get fresh meat from the whales. As more gulls learned the trick, the problems for whales increased. The gulls wait until a whale surfaces for air, then tear holes in the whales’ flesh and rip off pieces of skin and blubber. Each time the whales come back up, the gulls go in for more.
“It really worries us because the damage they’re doing to the whales is multiplying, especially to infant whales that are born in these waters,” Marcelo Bertellotti, of the National Patagonia Center, a government-sponsored conservation agency, told the AP.
The whales have had to change their behavior, according to Bertellolli. The whales no longer leap from the water or display their massive tails. Instead they break the surface just long enough to gulp in some air and then retreat to the safety of the depths.
Bertellotti advocates gunning down the gulls to protect the whales. By culling out the birds that have learned the whale bushwhack technique, he hopes to erase the habit from the population.
Read more at Disocvery News
The macabre torment of the whales sounds like a punishment from vengeful gods in a Greek myth or the plot of a Edgar Allan Poe story, but the real reason gulls have turned on the whales may be a bunch of garbage. Open air trash heaps near coastal cities have fueled a massive population boom in gulls. Fishermen add to the problem when they throw fish parts back into the ocean.
About eight years ago, the burgeoning gull population around the city of Puerto Madryn learned that they can get fresh meat from the whales. As more gulls learned the trick, the problems for whales increased. The gulls wait until a whale surfaces for air, then tear holes in the whales’ flesh and rip off pieces of skin and blubber. Each time the whales come back up, the gulls go in for more.
“It really worries us because the damage they’re doing to the whales is multiplying, especially to infant whales that are born in these waters,” Marcelo Bertellotti, of the National Patagonia Center, a government-sponsored conservation agency, told the AP.
The whales have had to change their behavior, according to Bertellolli. The whales no longer leap from the water or display their massive tails. Instead they break the surface just long enough to gulp in some air and then retreat to the safety of the depths.
Bertellotti advocates gunning down the gulls to protect the whales. By culling out the birds that have learned the whale bushwhack technique, he hopes to erase the habit from the population.
Read more at Disocvery News
Aug 28, 2012
A New Look at Proteins in Living Cells
Proteins adorning the surfaces of human cells perform an array of essential functions, including cell signaling, communication and the transport of vital substances into and out of cells. They are critical targets for drug delivery and many proteins are now being identified as disease biomarkers -- early warning beacons announcing the pre-symptomatic presence of cancers and other diseases.
While study of the binding properties of membrane proteins is essential, detailed analysis of these complex entities is tricky. Now, Nongjian (NJ) Tao, Professor of Electrical Engineering, and director of the Center for Bioelectronics and Biosensors at Arizona State University's Biodesign Institute has devised a new technique for examining the binding kinetics of membrane proteins.
"This is a very important but very difficult problem to solve," Tao notes. "We demonstrate a new method of approaching the issue, which provides a quantitative analysis of protein interactions on the surface of a cell."
The technique -- known as SPR microscopy -- holds the potential to simplify the study of membrane proteins, thereby streamlining the development of new drugs, aiding the identification of diagnostic biomarkers and improving the understanding of cell-pathogen interactions.
The group's results appear in this week's advanced online issue of the journal Nature Chemistry.
Typically, proteins attached to or embedded in the cell membrane's lipid bilayer are either tagged with fluorescent markers or extracted from their locations, purified and immobilized on a glass surface in protein microarrays. These efforts may not accurately reflect native configuration and function.
Membrane proteins are complex structures whose subtle performance is often related to alterations in conformation and the particular binding kinetics at work. Existing techniques using florescent markers have been applied to pinpoint binding events, but these only permit the visualization of the protein before and after binding, omitting the dynamic processes evolving over time. Further, the use of fluorescent labels to tag protein molecules can interfere with the processes researchers hope to observe.
Alternately, proteins are extracted, purified and affixed to microarray slides -- a labor-intensive process that removes proteins from their native environment, potentially affecting the shapes they naturally assume in situ and/or altering protein function.
In the current study, a label-free imaging technique is applied in situ to membrane proteins, which are visualized using a property known as surface plasmon resonance. This effect occurs when polarized light strikes the surface of a glass slide coated with a thin metallic film of gold. Under proper conditions of wavelength, polarization and incident angle, free electrons in the metal film absorb incident photons, converting them into plasmon waves, which propagate much like waves in water.
When nanoscale phenomena, including membrane proteins, interact and disrupt plasmon waves, they cause a measurable change in light reflectivity, which the new microscopy method converts into an image. (Figure 1a illustrates the basic setup of this technique.)
Surface plasmon resonance had already been applied to extracted proteins to study binding kinetics, though Tao explains that many steps are required and proteins may lose their proper conformational characteristics. This is particularly true for proteins normally embedded in a cell membrane's lipid matrix.
Another important consideration for the study of membrane proteins is the fact that that they arrange themselves heterogeneously across membrane surfaces and modify their distribution during various cellular activities. This behavior is particularly important during a process known as chemotaxis, when cells direct their movements under the influence of chemicals in the surrounding environment. For this reason, a tool allowing for both spatial and temporal study of membrane protein distribution in real time is highly desirable.
Tao's method uses surface plasmon resonance to provide high-resolution spatial and temporal information, and also allows for simultaneous optical and fluorescence observation of the sample, combining the advantages of both label-based and label-free methods.
High spatial resolution proved particularly useful for observing the ways polarized membrane proteins (bearing hydrophobic and hydrophilic regions) rearrange themselves, assisting cell migration directed by surrounding chemicals. The phenomenon also plays an important role during immune recognition. Using SPR microscopy, the spatial distribution of membrane proteins in single cells during chemotaxis could be mapped in detail for the first time, using a chemoattractant to induce cell migration.
Cells for study are cultured directly on a gold-coated slide, which can be subjected to simultaneous bright-field, florescent and SPR imaging. A liquid containing binding ligands is then applied over cells and the binding events with cell surface proteins monitored with SPR.
The technique permits millisecond resolution of temporal events and sub-micron scale analysis of spatial distribution. (See Figure 1b). In the current study, the method examined the binding of membrane glycoproteins with lectin ligands, the spatial distribution of membrane receptor molecules and membrane protein polarization and redistribution events.
The versatility of the new method, allowing for simultaneous imaging in optical, fluorescent and SPR modes, promises to significantly expand the study of membrane proteins in their native state, improving the understanding of protein binding kinetics and speeding the development of drugs targeting membrane proteins.
Read more at Science Daily
While study of the binding properties of membrane proteins is essential, detailed analysis of these complex entities is tricky. Now, Nongjian (NJ) Tao, Professor of Electrical Engineering, and director of the Center for Bioelectronics and Biosensors at Arizona State University's Biodesign Institute has devised a new technique for examining the binding kinetics of membrane proteins.
"This is a very important but very difficult problem to solve," Tao notes. "We demonstrate a new method of approaching the issue, which provides a quantitative analysis of protein interactions on the surface of a cell."
The technique -- known as SPR microscopy -- holds the potential to simplify the study of membrane proteins, thereby streamlining the development of new drugs, aiding the identification of diagnostic biomarkers and improving the understanding of cell-pathogen interactions.
The group's results appear in this week's advanced online issue of the journal Nature Chemistry.
Typically, proteins attached to or embedded in the cell membrane's lipid bilayer are either tagged with fluorescent markers or extracted from their locations, purified and immobilized on a glass surface in protein microarrays. These efforts may not accurately reflect native configuration and function.
Membrane proteins are complex structures whose subtle performance is often related to alterations in conformation and the particular binding kinetics at work. Existing techniques using florescent markers have been applied to pinpoint binding events, but these only permit the visualization of the protein before and after binding, omitting the dynamic processes evolving over time. Further, the use of fluorescent labels to tag protein molecules can interfere with the processes researchers hope to observe.
Alternately, proteins are extracted, purified and affixed to microarray slides -- a labor-intensive process that removes proteins from their native environment, potentially affecting the shapes they naturally assume in situ and/or altering protein function.
In the current study, a label-free imaging technique is applied in situ to membrane proteins, which are visualized using a property known as surface plasmon resonance. This effect occurs when polarized light strikes the surface of a glass slide coated with a thin metallic film of gold. Under proper conditions of wavelength, polarization and incident angle, free electrons in the metal film absorb incident photons, converting them into plasmon waves, which propagate much like waves in water.
When nanoscale phenomena, including membrane proteins, interact and disrupt plasmon waves, they cause a measurable change in light reflectivity, which the new microscopy method converts into an image. (Figure 1a illustrates the basic setup of this technique.)
Surface plasmon resonance had already been applied to extracted proteins to study binding kinetics, though Tao explains that many steps are required and proteins may lose their proper conformational characteristics. This is particularly true for proteins normally embedded in a cell membrane's lipid matrix.
Another important consideration for the study of membrane proteins is the fact that that they arrange themselves heterogeneously across membrane surfaces and modify their distribution during various cellular activities. This behavior is particularly important during a process known as chemotaxis, when cells direct their movements under the influence of chemicals in the surrounding environment. For this reason, a tool allowing for both spatial and temporal study of membrane protein distribution in real time is highly desirable.
Tao's method uses surface plasmon resonance to provide high-resolution spatial and temporal information, and also allows for simultaneous optical and fluorescence observation of the sample, combining the advantages of both label-based and label-free methods.
High spatial resolution proved particularly useful for observing the ways polarized membrane proteins (bearing hydrophobic and hydrophilic regions) rearrange themselves, assisting cell migration directed by surrounding chemicals. The phenomenon also plays an important role during immune recognition. Using SPR microscopy, the spatial distribution of membrane proteins in single cells during chemotaxis could be mapped in detail for the first time, using a chemoattractant to induce cell migration.
Cells for study are cultured directly on a gold-coated slide, which can be subjected to simultaneous bright-field, florescent and SPR imaging. A liquid containing binding ligands is then applied over cells and the binding events with cell surface proteins monitored with SPR.
The technique permits millisecond resolution of temporal events and sub-micron scale analysis of spatial distribution. (See Figure 1b). In the current study, the method examined the binding of membrane glycoproteins with lectin ligands, the spatial distribution of membrane receptor molecules and membrane protein polarization and redistribution events.
The versatility of the new method, allowing for simultaneous imaging in optical, fluorescent and SPR modes, promises to significantly expand the study of membrane proteins in their native state, improving the understanding of protein binding kinetics and speeding the development of drugs targeting membrane proteins.
Read more at Science Daily
We Are More Easily Influenced When We Follow Our Heart
When we let our hearts choose for us, we are more influenced by people who resemble ourselves, a PhD study from BI Norwegian Business School shows.
Every day we have to make a number of choices, and it is not always easy to know what the right choice is. That is why we often seek advice from others before making decisions. The Internet provides us with entirely new ways of finding out what other people feel about different products and services.
Many of us book hotel rooms online. Unless we are already familiar with the hotel, we will probably read reviews by former guests at the hotel before making up our minds. Such reviews are written by many different types of guests, families with small children, families with older children, single travellers, older guests and many other groups.
If you are a 25 year old student, for instance, you might attach different weight to a review from a student of your own age (the reviewer is similar to you) than you would to the comments from a 60 year old professor (who is different from you).
Influence from those who are similar
In his PhD study at BI Norwegian Business School, Ali Faraji Rad has conducted seven experiments to see whether we are more easily persuaded by people who are similar to us than by people who are dissimilar to us. He also looked at what circumstance might make the differences greater.
In all the experiments, participants were asked to imagine that they were going to book a hotel room online, and that they were reading a review of the hotel they were considering. Participants were then given a negative review of this hotel, along with a profile of the reviewer. The profiles were designed to create a feeling of similarity or dissimilarity with the participant in the experiment.
"Participants were more influenced by reviewers who were similar to themselves than by reviewers who were dissimilar. This difference was greatest when the choice of hotels was based on emotions and not logic," explains Ali Faraji Rad.
Logic and feelings
In the first experiment, half of the participants were asked to use logic in evaluating the hotel, while the others were was asked to base their evaluation on feelings. Those participants who based their evaluation on feelings, were influenced by reviewers similar to themselves.
Similar reviewers had no influence on participants who chose their hotel room on the basis of common sense and logic.
In the second experiment, half the participants were asked to write down some thoughts on why it is good to use logic when making decisions, while the other half was asked to write about why it is good to use our emotions when making decisions.
In this way, participants were primed to base their choice on logic or emotions.
The second experiment showed the same results as the first one. Participants who used their emotions were influenced, while those who followed their sense of logic were unaffected by reviewers who resembled themselves.
Business or pleasure
In experiments 3 and 4, Ali Faraji Rad instructed half of the participants to imagine that they were going away for fun, while the other half thought they would be travelling with work.
Previous studies have shown that we are more likely to use our emotions when we travel for fun than if we have more functional motives (such as a business trip).
Those participants who were thinking of a trip for fun were, as expected, more affected by the similar reviewer than those who were told to imagine a business trip.
Near and within reach
One half of the participants in the fifth experiment were asked to evaluate the hotel and imagine that they would be travelling next week, while the others were told they would be going in a year's time.
Participants who thought they were going next week were more influenced by similar reviewers than those who were to travel in a year's time. "Our choices are more based on emotions when they concern the near future."
In the sixth experiment, half the participants were told to imagine they were in a lottery where the chance of winning the hotel package was 1 to 5, while the other half received much longer odds, 1 to 5000.
Participants with the best chance of winning were more influenced by the similar reviewer than participants with longer odds.
"With a good chance of winning we feel that the trip is within reach, and we base our choice more on feelings," says Faraji-Rad.
Read more at Science Daily
Every day we have to make a number of choices, and it is not always easy to know what the right choice is. That is why we often seek advice from others before making decisions. The Internet provides us with entirely new ways of finding out what other people feel about different products and services.
Many of us book hotel rooms online. Unless we are already familiar with the hotel, we will probably read reviews by former guests at the hotel before making up our minds. Such reviews are written by many different types of guests, families with small children, families with older children, single travellers, older guests and many other groups.
If you are a 25 year old student, for instance, you might attach different weight to a review from a student of your own age (the reviewer is similar to you) than you would to the comments from a 60 year old professor (who is different from you).
Influence from those who are similar
In his PhD study at BI Norwegian Business School, Ali Faraji Rad has conducted seven experiments to see whether we are more easily persuaded by people who are similar to us than by people who are dissimilar to us. He also looked at what circumstance might make the differences greater.
In all the experiments, participants were asked to imagine that they were going to book a hotel room online, and that they were reading a review of the hotel they were considering. Participants were then given a negative review of this hotel, along with a profile of the reviewer. The profiles were designed to create a feeling of similarity or dissimilarity with the participant in the experiment.
"Participants were more influenced by reviewers who were similar to themselves than by reviewers who were dissimilar. This difference was greatest when the choice of hotels was based on emotions and not logic," explains Ali Faraji Rad.
Logic and feelings
In the first experiment, half of the participants were asked to use logic in evaluating the hotel, while the others were was asked to base their evaluation on feelings. Those participants who based their evaluation on feelings, were influenced by reviewers similar to themselves.
Similar reviewers had no influence on participants who chose their hotel room on the basis of common sense and logic.
In the second experiment, half the participants were asked to write down some thoughts on why it is good to use logic when making decisions, while the other half was asked to write about why it is good to use our emotions when making decisions.
In this way, participants were primed to base their choice on logic or emotions.
The second experiment showed the same results as the first one. Participants who used their emotions were influenced, while those who followed their sense of logic were unaffected by reviewers who resembled themselves.
Business or pleasure
In experiments 3 and 4, Ali Faraji Rad instructed half of the participants to imagine that they were going away for fun, while the other half thought they would be travelling with work.
Previous studies have shown that we are more likely to use our emotions when we travel for fun than if we have more functional motives (such as a business trip).
Those participants who were thinking of a trip for fun were, as expected, more affected by the similar reviewer than those who were told to imagine a business trip.
Near and within reach
One half of the participants in the fifth experiment were asked to evaluate the hotel and imagine that they would be travelling next week, while the others were told they would be going in a year's time.
Participants who thought they were going next week were more influenced by similar reviewers than those who were to travel in a year's time. "Our choices are more based on emotions when they concern the near future."
In the sixth experiment, half the participants were told to imagine they were in a lottery where the chance of winning the hotel package was 1 to 5, while the other half received much longer odds, 1 to 5000.
Participants with the best chance of winning were more influenced by the similar reviewer than participants with longer odds.
"With a good chance of winning we feel that the trip is within reach, and we base our choice more on feelings," says Faraji-Rad.
Read more at Science Daily
230-Million-Year-Old Fly and Mites Found in Amber
The oldest known amber-preserved fly and mites have just been discovered in northeastern Italy.
The specimens date to 230 million years ago, a time that interestingly coincides with the appearance of the world's first dinosaurs.
The mites didn't bite into dinosaurs, which was good news for the dinos, perhaps, but bad news for those hoping for some dino DNA.
The mites represent two new species, named Triasacarus fedelei and Ampezzoa triassica. They are the oldest fossils in an extremely specialized group called Eriophyoidea that has about 3,500 living species, all of which feed on plants and sometimes form abnormal growth called galls. The ancient gall mites are surprisingly similar to ones seen today.
"You would think that by going back to the Triassic you'd find a transitional form of gall mite, but no," said David Grimaldi, a curator in the American Museum of Natural History’s Division of Invertebrate Zoology, in a press release. "Even 230 million years ago, all of the distinguishing features of this family were there -- a long, segmented body; only two pairs of legs instead of the usual four found in mites; unique feather claws, and mouthparts."
The ancient mites likely fed on the leaves of the tree that ultimately preserved them, a conifer in the extinct family Cheirolepidiaceae. The mites are so old that they pre-date the existence of flowering plants.
"We now know that gall mites are very adaptable," Grimaldi said. "When flowering plants entered the scene, these mites shifted their feeding habits, and today, only 3 percent of the species live on conifers. This shows how gall mites tracked plants in time and evolved with their hosts."
As for the fly, the researchers aren't sure what kind it was. The amber pieces are very small, so when the invertebrates kicked the bucket by drowning in tree resin, they were entombed in mere drops of the stuff.
"Amber is an extremely valuable tool for paleontologists because it preserves specimens with microscopic fidelity, allowing uniquely accurate estimates of the amount of evolutionary change over millions of years," Grimaldi, who is a world authority on amber and fossil arthropods, said.
Read more at Discovery News
The specimens date to 230 million years ago, a time that interestingly coincides with the appearance of the world's first dinosaurs.
The mites didn't bite into dinosaurs, which was good news for the dinos, perhaps, but bad news for those hoping for some dino DNA.
The mites represent two new species, named Triasacarus fedelei and Ampezzoa triassica. They are the oldest fossils in an extremely specialized group called Eriophyoidea that has about 3,500 living species, all of which feed on plants and sometimes form abnormal growth called galls. The ancient gall mites are surprisingly similar to ones seen today.
"You would think that by going back to the Triassic you'd find a transitional form of gall mite, but no," said David Grimaldi, a curator in the American Museum of Natural History’s Division of Invertebrate Zoology, in a press release. "Even 230 million years ago, all of the distinguishing features of this family were there -- a long, segmented body; only two pairs of legs instead of the usual four found in mites; unique feather claws, and mouthparts."
The ancient mites likely fed on the leaves of the tree that ultimately preserved them, a conifer in the extinct family Cheirolepidiaceae. The mites are so old that they pre-date the existence of flowering plants.
"We now know that gall mites are very adaptable," Grimaldi said. "When flowering plants entered the scene, these mites shifted their feeding habits, and today, only 3 percent of the species live on conifers. This shows how gall mites tracked plants in time and evolved with their hosts."
As for the fly, the researchers aren't sure what kind it was. The amber pieces are very small, so when the invertebrates kicked the bucket by drowning in tree resin, they were entombed in mere drops of the stuff.
"Amber is an extremely valuable tool for paleontologists because it preserves specimens with microscopic fidelity, allowing uniquely accurate estimates of the amount of evolutionary change over millions of years," Grimaldi, who is a world authority on amber and fossil arthropods, said.
Read more at Discovery News
Artificial Universe Created Inside a Supercomputer
Building a universe from scratch that brims with galaxies resembling those around us is now possible on supercomputers for the first time, researchers say.
Our galaxy, the Milky Way, is a spiral galaxy with a broad disk and outstretched arms, as are many in our cosmic neighborhood, such as Andromeda, the Pinwheel and the Whirlpool galaxies. Spiral galaxies are common, but past computer models that aimed to accurately simulate the birth and evolution of the universe over billions of years had trouble creating them. Instead, they often generated lots of blobby galaxies clumped into balls.
New computer simulations can now recreate the kind of galactic communities seen in our universe, starting with the observed afterglow of the Big Bang and evolving forward in time. Harvard's Odyssey supercomputer allowed simulations that compressed nearly 14 billion years into only a few months.
"We've created the full variety of galaxies we see in the local universe," said study author Mark Vogelsberger at the Harvard-Smithsonian Center for Astrophysics.
The new software is called Arepo and was created by Volker Springel at the Heidelberg Institute for Theoretical Studies in Germany. Previous simulations divided space into a fixed grid of cubes, with each cube simulating the behavior of substances within that space.
Arepo uses a grid that can reshape itself, filling itself with tetrahedrons of varying size and shape (a tetrahedron is a four-sided object resembling a pyramid). The more substance a region contains, such as gas, stars, dark matter or dark energy, the more tetrahedra Arepo devotes to that region, which enables it to simulate the behavior and flow of these substances more accurately.
"We took all the advantages of previous codes and removed the disadvantages," Springel said.
"I would like to add that the simulations we've run with our software represent a universe or slice of the universe that has many properties similar to our own, but it's not necessarily the same universe," astrophysicist Paul Torrey at the Harvard-Smithsonian Center for Astrophysics told SPACE.com. "While you may find many galaxies like the Milky Way in it, you won't find the Milky Way itself."
Read more at Discovery News
Our galaxy, the Milky Way, is a spiral galaxy with a broad disk and outstretched arms, as are many in our cosmic neighborhood, such as Andromeda, the Pinwheel and the Whirlpool galaxies. Spiral galaxies are common, but past computer models that aimed to accurately simulate the birth and evolution of the universe over billions of years had trouble creating them. Instead, they often generated lots of blobby galaxies clumped into balls.
New computer simulations can now recreate the kind of galactic communities seen in our universe, starting with the observed afterglow of the Big Bang and evolving forward in time. Harvard's Odyssey supercomputer allowed simulations that compressed nearly 14 billion years into only a few months.
"We've created the full variety of galaxies we see in the local universe," said study author Mark Vogelsberger at the Harvard-Smithsonian Center for Astrophysics.
The new software is called Arepo and was created by Volker Springel at the Heidelberg Institute for Theoretical Studies in Germany. Previous simulations divided space into a fixed grid of cubes, with each cube simulating the behavior of substances within that space.
Arepo uses a grid that can reshape itself, filling itself with tetrahedrons of varying size and shape (a tetrahedron is a four-sided object resembling a pyramid). The more substance a region contains, such as gas, stars, dark matter or dark energy, the more tetrahedra Arepo devotes to that region, which enables it to simulate the behavior and flow of these substances more accurately.
"We took all the advantages of previous codes and removed the disadvantages," Springel said.
"I would like to add that the simulations we've run with our software represent a universe or slice of the universe that has many properties similar to our own, but it's not necessarily the same universe," astrophysicist Paul Torrey at the Harvard-Smithsonian Center for Astrophysics told SPACE.com. "While you may find many galaxies like the Milky Way in it, you won't find the Milky Way itself."
Read more at Discovery News
Aug 27, 2012
How Methane Becomes Fish Food
Methane is an organic carbon compound containing the fundamental building block of nearly all living material: carbon. It provides an important source of energy and nutrients for bacteria. Methane is produced in oxygen-free environments and is found in abundance at the bottom of lakes.
The Brazilian post-doctoral researcher in biology and ecology, Angela Sanseverino, has presented a study that shows methane from lakebeds to be present in fish tissue. The study was carried out in cooperation with, inter alia, David Bastviken, Water and Environmental Studies (WES), Linköping University.
Angela Sanseverino has studied a combination of two biomarkers: a stable isotope that indicates the presence of methane along with a specific fatty acid from methane-oxidizing bacteria. The study was carried out on fish and other parts of the food web from a lake in the Pantanal, inland Brazil. The findings of the study have been reported in a recently published article in the online research journal PLoS ONE.
"This is the first time we can say with any great certainty that methane from the lake bed has ended up in fish tissue via the food chain," says David Bastviken. "Isotopic studies have been carried out in the past, but they have been more uncertain as they only related to one biomarker. We now have two independent biomarkers presenting the same results. This considerably increases the certainty of our findings."
"It is like opening a black box. It turns out that carbon, which we thought was lost forever, can return to the food chain."
Methane is taken up by methane oxidizing bacteria, which in turn are eaten by zooplankton and other aquatic organisms. These organisms eventually end up in fish stomachs, meaning that food webs not only feed off organic carbon from plants in the lake or from the surrounding land; but also from deep-lying and oxygen-free, yet carbon-rich, sediment stores where methane is formed.
More studies are being planned to show the potentially vast importance that methane could have on the food chain in different types of lakes and conditions. For example, what happens in Swedish lakes during the winter?
Read more at Science Daily
The Brazilian post-doctoral researcher in biology and ecology, Angela Sanseverino, has presented a study that shows methane from lakebeds to be present in fish tissue. The study was carried out in cooperation with, inter alia, David Bastviken, Water and Environmental Studies (WES), Linköping University.
Angela Sanseverino has studied a combination of two biomarkers: a stable isotope that indicates the presence of methane along with a specific fatty acid from methane-oxidizing bacteria. The study was carried out on fish and other parts of the food web from a lake in the Pantanal, inland Brazil. The findings of the study have been reported in a recently published article in the online research journal PLoS ONE.
"This is the first time we can say with any great certainty that methane from the lake bed has ended up in fish tissue via the food chain," says David Bastviken. "Isotopic studies have been carried out in the past, but they have been more uncertain as they only related to one biomarker. We now have two independent biomarkers presenting the same results. This considerably increases the certainty of our findings."
"It is like opening a black box. It turns out that carbon, which we thought was lost forever, can return to the food chain."
Methane is taken up by methane oxidizing bacteria, which in turn are eaten by zooplankton and other aquatic organisms. These organisms eventually end up in fish stomachs, meaning that food webs not only feed off organic carbon from plants in the lake or from the surrounding land; but also from deep-lying and oxygen-free, yet carbon-rich, sediment stores where methane is formed.
More studies are being planned to show the potentially vast importance that methane could have on the food chain in different types of lakes and conditions. For example, what happens in Swedish lakes during the winter?
Read more at Science Daily
Fossil Skeleton of Strange, Ancient Digging Mammal Clears Up 30-Year-Old Evolutionary Debate
Shortly after dinosaurs like Tyrannosaurus and Triceratops went extinct 65 million years ago, Earth's ancient landscapes were filled with unusual mammals only distantly related to those alive today. Until recently, one of these creatures, Ernanodon antelios, was only known from a single, highly distorted specimen that raised many questions about its habits and evolutionary relationships.
In the most recent issue of the Journal of Vertebrate Paleontology, scientists describe a second specimen of Ernanodon that sheds new light on this curious beast from the dawn of the "Age of Mammals."
The remarkable new skeleton comes from rocks in Mongolia that were deposited 57 million years ago during a period known as the Paleocene Epoch.
"Ernanodon is a unique find and represents one of the most complete skeletons ever collected from the Paleocene of the Naran Bulak locality," said Alexander Agadjanian of the Borissiak Paleontological Institute of the Russian Academy of Sciences, co-author of the study.
The first specimen was discovered by a team of Soviet paleontologists in 1979 but remained unstudied for more than thirty years. The new specimen preserves most of the arms, legs, and backbone of the badger-sized animal, including many bones that were not preserved in the first specimen. The authors of the new study made detailed comparisons among the bones of Ernanodon and those of modern mammals and concluded that Ernanodon was highly specialized for digging. It may have dug for food, for shelter, or both.
"Only a handful of Asian Paleocene mammals are known by their postcranial skeleton, which makes Ernanodon a unique source of very important information about its habits, lifestyle, and affinities," said Peter Kondrashov of A.T. Still University of Health Sciences, lead author of the study.
The strong limbs and large claws of Ernanodon, combined with its unusual, simplified teeth, have caused much confusion about its evolutionary relationships. Some scientists thought Ernanodon was an ancient relative of modern armadillos and anteaters, whereas other scientists thought Ernanodon was more closely related to a group of African and Asian ant-eating mammals known as pangolins or "scaly anteaters." The new study concludes that Ernanodon was a closer relative of pangolins than armadillos and anteaters, but that it represents a very early side branch of the pangolin family tree.
Read more at Science Daily
In the most recent issue of the Journal of Vertebrate Paleontology, scientists describe a second specimen of Ernanodon that sheds new light on this curious beast from the dawn of the "Age of Mammals."
The remarkable new skeleton comes from rocks in Mongolia that were deposited 57 million years ago during a period known as the Paleocene Epoch.
"Ernanodon is a unique find and represents one of the most complete skeletons ever collected from the Paleocene of the Naran Bulak locality," said Alexander Agadjanian of the Borissiak Paleontological Institute of the Russian Academy of Sciences, co-author of the study.
The first specimen was discovered by a team of Soviet paleontologists in 1979 but remained unstudied for more than thirty years. The new specimen preserves most of the arms, legs, and backbone of the badger-sized animal, including many bones that were not preserved in the first specimen. The authors of the new study made detailed comparisons among the bones of Ernanodon and those of modern mammals and concluded that Ernanodon was highly specialized for digging. It may have dug for food, for shelter, or both.
"Only a handful of Asian Paleocene mammals are known by their postcranial skeleton, which makes Ernanodon a unique source of very important information about its habits, lifestyle, and affinities," said Peter Kondrashov of A.T. Still University of Health Sciences, lead author of the study.
The strong limbs and large claws of Ernanodon, combined with its unusual, simplified teeth, have caused much confusion about its evolutionary relationships. Some scientists thought Ernanodon was an ancient relative of modern armadillos and anteaters, whereas other scientists thought Ernanodon was more closely related to a group of African and Asian ant-eating mammals known as pangolins or "scaly anteaters." The new study concludes that Ernanodon was a closer relative of pangolins than armadillos and anteaters, but that it represents a very early side branch of the pangolin family tree.
Read more at Science Daily
Ape 'Genius' Smarter Than the Average Chimp
Certain apes appear to be much smarter than others, with at least one chimpanzee now called "exceptional" when compared to other chimps.
The standout chimp, an adult female in her 20s named Natasha, scored off the charts in a battery of tests. The findings, published in the latest Philosophical Transactions of the Royal Society B, suggest that geniuses exist among non-humans, but that no one attribute constitutes intelligence.
Instead, a perfect storm of abilities seems to come together to create the Einsteins of the animal kingdom. Natasha's keepers at the Ngamba Island chimpanzee sanctuary in Uganda knew she was special even before the latest study.
"The caretakers named Natasha as the smartest chimpanzee, precisely the same chimpanzee that our tests had revealed to be exceptional," study authors Esther Herrmann and Josep Call of the Max Planck Institute for Evolutionary Anthropology wrote.
"All three of the most experienced caretakers included Natasha in their lists (of the most intelligent chimps)," they added.
Natasha has made headlines over the months for her attention-grabbing antics. For instance, she repeatedly escaped her former enclosure, surrounded by an electric fence. She did this by tossing branches at the fence until she didn't see a spark, letting her know that the power was off.
She also learned how to tease humans, beckoning them to throw food her way, only to spray the unsuspecting person with water.
Herrmann and Call decided to study this chimp, along with numerous others, to see if there really are chimp prodigies among non-human great apes. To do this, the researchers created a multi-part mental challenge consisting of eight tasks.
For the first task, the chimps had to find hidden food, testing their spatial knowledge. For the second, the chimps wielded a tool -- avoiding a trap -- to again obtain a food reward. The remaining tasks demonstrated understanding of things like color, size and shape.
"We identified some individuals who consistently scored well across (the) multiple tasks," wrote the authors, who again made note of Natasha, who aced nearly every task.
The researchers could not identify "a general intelligence factor." They instead indicate that ape intelligence might be a bundling of skills related to learning, tool usage, understanding of quantities, and an ability to reach conclusions based on evidence and reasoning.
As the saying goes, necessity may be the mother of invention and, at least in some cases, one reason behind chimp cleverness.
Call, for example, told Discovery News about chimps that make tools for extracting termites out of mounds. The process requires several steps.
"They uproot the stem or use their teeth to clip the stem at the base and then remove the large leaf from the distal end by clipping it with their teeth before transporting the stem to the termite nest, where they complete tool manufacture by modifying the end into a 'paint brush' tip by pulling the stem through their teeth, splitting the probe lengthwise by pulling off strands of fiber, or separating the fibers by biting them," he said.
Read more at Discovery News
The standout chimp, an adult female in her 20s named Natasha, scored off the charts in a battery of tests. The findings, published in the latest Philosophical Transactions of the Royal Society B, suggest that geniuses exist among non-humans, but that no one attribute constitutes intelligence.
Instead, a perfect storm of abilities seems to come together to create the Einsteins of the animal kingdom. Natasha's keepers at the Ngamba Island chimpanzee sanctuary in Uganda knew she was special even before the latest study.
"The caretakers named Natasha as the smartest chimpanzee, precisely the same chimpanzee that our tests had revealed to be exceptional," study authors Esther Herrmann and Josep Call of the Max Planck Institute for Evolutionary Anthropology wrote.
"All three of the most experienced caretakers included Natasha in their lists (of the most intelligent chimps)," they added.
Natasha has made headlines over the months for her attention-grabbing antics. For instance, she repeatedly escaped her former enclosure, surrounded by an electric fence. She did this by tossing branches at the fence until she didn't see a spark, letting her know that the power was off.
She also learned how to tease humans, beckoning them to throw food her way, only to spray the unsuspecting person with water.
Herrmann and Call decided to study this chimp, along with numerous others, to see if there really are chimp prodigies among non-human great apes. To do this, the researchers created a multi-part mental challenge consisting of eight tasks.
For the first task, the chimps had to find hidden food, testing their spatial knowledge. For the second, the chimps wielded a tool -- avoiding a trap -- to again obtain a food reward. The remaining tasks demonstrated understanding of things like color, size and shape.
"We identified some individuals who consistently scored well across (the) multiple tasks," wrote the authors, who again made note of Natasha, who aced nearly every task.
The researchers could not identify "a general intelligence factor." They instead indicate that ape intelligence might be a bundling of skills related to learning, tool usage, understanding of quantities, and an ability to reach conclusions based on evidence and reasoning.
As the saying goes, necessity may be the mother of invention and, at least in some cases, one reason behind chimp cleverness.
Call, for example, told Discovery News about chimps that make tools for extracting termites out of mounds. The process requires several steps.
"They uproot the stem or use their teeth to clip the stem at the base and then remove the large leaf from the distal end by clipping it with their teeth before transporting the stem to the termite nest, where they complete tool manufacture by modifying the end into a 'paint brush' tip by pulling the stem through their teeth, splitting the probe lengthwise by pulling off strands of fiber, or separating the fibers by biting them," he said.
Read more at Discovery News
Neutrino Halo May Change Supernova 'Flavor'
When Carl Sagan said "we're made of star stuff" he wasn't kidding; there's no other way that the elements heavier than lithium could have been formed if it wasn't for the stellar kilns in the cores of stars or the violent eruption of supernovae.
In the case of a supernova, when a massive star runs out of fuel, it may collapse under gravity and then explode. During the detonation process, the supernova generates heavy elements that go on to seed planets, other stars and, ultimately, the elements that form organic compounds that we find inside our bodies.
But what elements are formed? And how do neutrinos affect the collapse of a massive star? Graduate student John Cherry, of the University of California, San Diego, thinks he's stumbled across an answer.
One type of supernova is known as a core-collapse supernova -- it occurs when a massive star is starved of fuel. When this happens, the rate of nuclear fusion slows in the core and gravity starts to take over. The core rapidly collapses.
During this process, a dense neutron star can suddenly form, causing a rebound of in-falling stellar material. At this point, neutrinos flood outward from the core, blasting through the shrinking stellar body.
Neutrinos are ghostly particles that zip through space unhindered. They are so weakly interacting that they can pass through the Earth without hitting any other particle. In fact, as I sit here typing at my computer, billions of neutrinos -- from the sun and other cosmic sources -- are passing through my body every second. (Aside: To detect neutrinos, huge caverns filled with water surrounded by sensors are used to detect the rare "flash" a neutrino will make when it happens to hit a water molecule head-on. These "accidental" collisions are very rare, so in the interest of statistical probability it helps to make your neutrino detector as large as possible.)
Inside a core collapse supernova, the density of the material is very high as it accretes into the core forming the neutron star. It is calculated that this material will interact with the outflowing neutrinos, scattering a small percentage of them. These scattered neutrinos create a "neutrino halo" that can, in turn, interact with the outflowing neutrinos.
But the fraction of outflowing neutrinos affected was thought to be minuscule and was often ignered during simulations. Cherry's calculations disagree, however -- his model suggests that a correction factor of 14 percent needs to be applied. In the outermost portions of the exploding supernova, this correction factor rose ten-fold. This means the neutrinos streaming from the core interacted with halo neutrinos far more often than previous theories anticipated.
What has this got to do with the price of eggs? Neutrinos are weakly interacting lightweights; a supernova literally shapes galaxies -- one has little effect on the other, right?
Actually, this neutrino halo interaction could directly influence the nature of the supernova, literally changing the types of elements that can be spawned from the stellar event. And it all comes down to flavor -- the "flavor" of neutrinos.
A strange little fact about neutrinos is that they come in three different varieties, or flavors -- electron, muon and tau. Three flavors may seem pretty limited when it comes to an ice cream shop, but to neutrinos, their flavor is critical. What's more, neutrinos can change their flavor.
Read more at Discovery News
In the case of a supernova, when a massive star runs out of fuel, it may collapse under gravity and then explode. During the detonation process, the supernova generates heavy elements that go on to seed planets, other stars and, ultimately, the elements that form organic compounds that we find inside our bodies.
But what elements are formed? And how do neutrinos affect the collapse of a massive star? Graduate student John Cherry, of the University of California, San Diego, thinks he's stumbled across an answer.
One type of supernova is known as a core-collapse supernova -- it occurs when a massive star is starved of fuel. When this happens, the rate of nuclear fusion slows in the core and gravity starts to take over. The core rapidly collapses.
During this process, a dense neutron star can suddenly form, causing a rebound of in-falling stellar material. At this point, neutrinos flood outward from the core, blasting through the shrinking stellar body.
Neutrinos are ghostly particles that zip through space unhindered. They are so weakly interacting that they can pass through the Earth without hitting any other particle. In fact, as I sit here typing at my computer, billions of neutrinos -- from the sun and other cosmic sources -- are passing through my body every second. (Aside: To detect neutrinos, huge caverns filled with water surrounded by sensors are used to detect the rare "flash" a neutrino will make when it happens to hit a water molecule head-on. These "accidental" collisions are very rare, so in the interest of statistical probability it helps to make your neutrino detector as large as possible.)
Inside a core collapse supernova, the density of the material is very high as it accretes into the core forming the neutron star. It is calculated that this material will interact with the outflowing neutrinos, scattering a small percentage of them. These scattered neutrinos create a "neutrino halo" that can, in turn, interact with the outflowing neutrinos.
But the fraction of outflowing neutrinos affected was thought to be minuscule and was often ignered during simulations. Cherry's calculations disagree, however -- his model suggests that a correction factor of 14 percent needs to be applied. In the outermost portions of the exploding supernova, this correction factor rose ten-fold. This means the neutrinos streaming from the core interacted with halo neutrinos far more often than previous theories anticipated.
What has this got to do with the price of eggs? Neutrinos are weakly interacting lightweights; a supernova literally shapes galaxies -- one has little effect on the other, right?
Actually, this neutrino halo interaction could directly influence the nature of the supernova, literally changing the types of elements that can be spawned from the stellar event. And it all comes down to flavor -- the "flavor" of neutrinos.
A strange little fact about neutrinos is that they come in three different varieties, or flavors -- electron, muon and tau. Three flavors may seem pretty limited when it comes to an ice cream shop, but to neutrinos, their flavor is critical. What's more, neutrinos can change their flavor.
Read more at Discovery News
Aug 26, 2012
Farewell Neil Armstrong, the Ultimate Test Pilot
Neil Armstrong — who has died at the age of 82 — was best known as the commander of Apollo 11, but his career at NASA began nearly a decade earlier as a research test pilot.
A trained aerospace engineer, Armstrong was a self-described “white-socks, pocket-protector, nerdy engineer” who worked at the cutting edge of flight test throughout the 1960s, flying everything from a hang-glider type aircraft towed behind a biplane, to a hypersonic rocket-powered airplane that flew to the edge of space.
Neil Armstrong was born in Wapakoneta, Ohio and first began building model airplanes while in elementary school. He told biographer James Hansen he initially wanted to be an airplane designer, but “later went into piloting because I thought a good designer ought to know the operational aspects of an airplane.”
The future astronaut soloed an airplane just a few weeks after his sixteenth birthday. Before being selected as an astronaut, Armstrong was a naval aviator flying F9F Panther fighter jets in the Korean War. After the war, he became a research pilot for the National Advisory Committee for Aeronautics, the predecessor to NASA. While a research pilot NACA and later NASA, he flew the rocket powered Bell X-1B and the North American X-15 along with a wide variety of jet and propeller aircraft totaling more than 200 different types.
During his time in the X-15 program, Armstrong demonstrated his engineering skills working on the hypersonic aircraft’s flight control system as well as the relatively primitive simulator used to develop flight profiles of the first winged aircraft to fly into space. During his highest of seven flights in the X-15, he climbed to 207,500 feet. After the engine stopped (as planned) and he was gliding back to land, Armstrong was testing a new control system when he bounced off the top of the atmosphere, skipping past Edwards Air Force Base in the Mojave Desert and not getting the rocket airplane turned around until flying near Pasadena.
He was fifty miles south of his landing spot in a rocket plane that was now a rather poor glider. But the calm engineer says, “that wasn’t a great concern to me because there were other dry lakes available.” He would later call the longest X-15 flight of all “a learning thing.” The entire flight lasted just 12 minutes, 28 seconds.
At the same time Armstrong was working on the X-15 program, he also worked on the Boeing X-20 Dyna-Soar project, part of the Air Force’s ‘Man in Space Soonest’ program. The X-20 was to be a winged spacecraft that was an early predecessor to the space shuttle orbiters. As a test pilot and engineer, Armstrong flew a modified Douglas F5D fighter jet — now on display at the Neil Armstrong Museum in Wapakoneta — on a series of flights to develop launch abort procedures that were to be used for the winged X-20 spacecraft.
Armstrong’s quiet engineering demeanor was perhaps best demonstrated after a flight in the Lunar Lander Training Vehicle (LLTV). Affectionately known as the “flying bedsteads,” the LLTV was used to train astronauts who would be making approaches to the lunar surface and was basically a large jet engine pointed downward and small thrusters that could control the attitude of the vehicle during flight.
It was considered a very difficult, and dangerous aircraft to fly. On a LLTV flight in 1968, Armstrong lost control of the aircraft due to a propellant leak and windy conditions. He ejected only moments before it crashed in a fireball. According to James Hansen’s biography, an hour or so later fellow astronaut Alan Bean returned to his desk after lunch and found Armstrong at his own desk simply “shuffling some papers.” Bean didn’t believe what others had told him about the crash so he asked Armstrong who replied, “I lost control and had to bail out of the darn thing.”
At a meeting of the Society of Experimental Test Pilots in 2007, Armstrong described the development and use of the LLTV.
Armstrong joined the astronaut corps as part of the “new nine” and first flew on Gemini 8 along with David Scott. The Gemini 8 mission was set to make the first rendezvous and docking with another spacecraft in orbit to test docking procedures. Upon docking with the Agena, an unmanned target vehicle, the Gemini spacecraft and Agena began spinning. Armstrong disconnected from the Agena and then began spinning even faster, approximately one revolution per second. Facing an unplanned flight test kind situation once again, Armstrong put his experience as a test pilot and engineer to work and decided to use the reentry control system to slow down the rotation. The solution worked, but cut short the flight which ended after less than 11 hours.
After the Gemini flight experience, Armstrong was the backup commander for Gemini 11 but did not fly to space. He was then selected as backup commander for Apollo 8, the first mission to leave earth orbit and circle the moon. In December of 1968, while Apollo 8 was still in space, Armstrong was offered the commander position for Apollo 11. At the time, there was no guarantee that meant he would be commanding the mission to the moon. There was still plenty that could go wrong forcing a delay and bumping a moon landing to Apollo 12 or later.
Apollo 8 was only the third flight for the massive Saturn V rocket, and the first carrying astronauts. The mission combined several tests that were initially expected to be spread over a few flights. The bold decision to proceed and successful Apollo 8 mission were critical in making Armstrong’s Apollo 11 flight to the moon possible. Armstrong later said in his biography: “I cannot imagine NASA management in any subsequent period of time being willing to take that kind of step.”
Of course, it was less than a year later that Armstrong himself would make the biggest step. After a three day trip to the moon, Armstrong, Aldrin and Collins entered lunar orbit on July 19. On July 20, Armstrong and Aldrin began their descent towards the surface inside Eagle, the lunar landing module. The flight to the surface did not quite go as planned. During the descent several alarms from the flight guidance computer distracted the astronauts. The onboard computers were inundated with extraneous radar information, but the alarms were determined not to be a problem.
But Armstrong also noticed he and Aldrin were flying faster than expected across the lunar surface and were likely going to overshoot their landing site. As the Eagle passed 1,500 feet above the surface, Armstrong saw they were heading for a crater. He thought this might be a good option as it would have “more scientific value to be close to a large crater.” But the steep slope and big rocks did not provide a safe place to land.
As they continued to fly over areas covered with large rocks and boulders, Armstrong took over control of the Eagle and continued flying it manually. He was able to use his training from the LLTV to maneuver as they continued to descend to the surface. But all of the maneuvering was using up propellant. At 200 feet above the surface, Armstrong finally was able to find a place to land.
Aldrin: Eleven [feet per second] forward. Coming down nicely. Two hundred feet, four and a half down.
Armstrong: Gonna be right over that crater.
Aldrin: Five and a half down.
Armstrong: I got a good spot.
Aldrin: One hundred and sixty feet, six and a half down. Five and a half down, nine forward. You’re looking good.
As they passed 75 feet mission control in Houston determined the Eagle only had 60 seconds of fuel left. Armstrong says he wasn’t terribly concerned about the low fuel situation, “typically in the LLTV it wasn’t unusual to land with 15 seconds left of fuel.”
About 40 seconds later Armstrong made a final few maneuvers before announcing the landing was complete.
Armstrong: Shutdown.
Aldrin: Okay. Engine stop.
Houston: We copy you down, Eagle.
Armstrong: Houston, Tranquility Base here. The Eagle has landed.
It was later determined the Eagle had about 50 seconds of fuel left for maneuvering. Most remember Neil Armstrong as the first person to walk on the moon. As a test pilot, he often referred to being the first person to land a spacecraft on the moon, something he liked to point out was the more challenging part of the mission from his point of view.
After his historic descent down the ladder and making his “giant leap for mankind” Armstrong and Aldrin would spend just two hours and 36 minutes on the surface of the moon.
Read more at Wired Science
A trained aerospace engineer, Armstrong was a self-described “white-socks, pocket-protector, nerdy engineer” who worked at the cutting edge of flight test throughout the 1960s, flying everything from a hang-glider type aircraft towed behind a biplane, to a hypersonic rocket-powered airplane that flew to the edge of space.
Neil Armstrong was born in Wapakoneta, Ohio and first began building model airplanes while in elementary school. He told biographer James Hansen he initially wanted to be an airplane designer, but “later went into piloting because I thought a good designer ought to know the operational aspects of an airplane.”
The future astronaut soloed an airplane just a few weeks after his sixteenth birthday. Before being selected as an astronaut, Armstrong was a naval aviator flying F9F Panther fighter jets in the Korean War. After the war, he became a research pilot for the National Advisory Committee for Aeronautics, the predecessor to NASA. While a research pilot NACA and later NASA, he flew the rocket powered Bell X-1B and the North American X-15 along with a wide variety of jet and propeller aircraft totaling more than 200 different types.
During his time in the X-15 program, Armstrong demonstrated his engineering skills working on the hypersonic aircraft’s flight control system as well as the relatively primitive simulator used to develop flight profiles of the first winged aircraft to fly into space. During his highest of seven flights in the X-15, he climbed to 207,500 feet. After the engine stopped (as planned) and he was gliding back to land, Armstrong was testing a new control system when he bounced off the top of the atmosphere, skipping past Edwards Air Force Base in the Mojave Desert and not getting the rocket airplane turned around until flying near Pasadena.
He was fifty miles south of his landing spot in a rocket plane that was now a rather poor glider. But the calm engineer says, “that wasn’t a great concern to me because there were other dry lakes available.” He would later call the longest X-15 flight of all “a learning thing.” The entire flight lasted just 12 minutes, 28 seconds.
At the same time Armstrong was working on the X-15 program, he also worked on the Boeing X-20 Dyna-Soar project, part of the Air Force’s ‘Man in Space Soonest’ program. The X-20 was to be a winged spacecraft that was an early predecessor to the space shuttle orbiters. As a test pilot and engineer, Armstrong flew a modified Douglas F5D fighter jet — now on display at the Neil Armstrong Museum in Wapakoneta — on a series of flights to develop launch abort procedures that were to be used for the winged X-20 spacecraft.
Armstrong’s quiet engineering demeanor was perhaps best demonstrated after a flight in the Lunar Lander Training Vehicle (LLTV). Affectionately known as the “flying bedsteads,” the LLTV was used to train astronauts who would be making approaches to the lunar surface and was basically a large jet engine pointed downward and small thrusters that could control the attitude of the vehicle during flight.
It was considered a very difficult, and dangerous aircraft to fly. On a LLTV flight in 1968, Armstrong lost control of the aircraft due to a propellant leak and windy conditions. He ejected only moments before it crashed in a fireball. According to James Hansen’s biography, an hour or so later fellow astronaut Alan Bean returned to his desk after lunch and found Armstrong at his own desk simply “shuffling some papers.” Bean didn’t believe what others had told him about the crash so he asked Armstrong who replied, “I lost control and had to bail out of the darn thing.”
At a meeting of the Society of Experimental Test Pilots in 2007, Armstrong described the development and use of the LLTV.
Armstrong joined the astronaut corps as part of the “new nine” and first flew on Gemini 8 along with David Scott. The Gemini 8 mission was set to make the first rendezvous and docking with another spacecraft in orbit to test docking procedures. Upon docking with the Agena, an unmanned target vehicle, the Gemini spacecraft and Agena began spinning. Armstrong disconnected from the Agena and then began spinning even faster, approximately one revolution per second. Facing an unplanned flight test kind situation once again, Armstrong put his experience as a test pilot and engineer to work and decided to use the reentry control system to slow down the rotation. The solution worked, but cut short the flight which ended after less than 11 hours.
After the Gemini flight experience, Armstrong was the backup commander for Gemini 11 but did not fly to space. He was then selected as backup commander for Apollo 8, the first mission to leave earth orbit and circle the moon. In December of 1968, while Apollo 8 was still in space, Armstrong was offered the commander position for Apollo 11. At the time, there was no guarantee that meant he would be commanding the mission to the moon. There was still plenty that could go wrong forcing a delay and bumping a moon landing to Apollo 12 or later.
Apollo 8 was only the third flight for the massive Saturn V rocket, and the first carrying astronauts. The mission combined several tests that were initially expected to be spread over a few flights. The bold decision to proceed and successful Apollo 8 mission were critical in making Armstrong’s Apollo 11 flight to the moon possible. Armstrong later said in his biography: “I cannot imagine NASA management in any subsequent period of time being willing to take that kind of step.”
Of course, it was less than a year later that Armstrong himself would make the biggest step. After a three day trip to the moon, Armstrong, Aldrin and Collins entered lunar orbit on July 19. On July 20, Armstrong and Aldrin began their descent towards the surface inside Eagle, the lunar landing module. The flight to the surface did not quite go as planned. During the descent several alarms from the flight guidance computer distracted the astronauts. The onboard computers were inundated with extraneous radar information, but the alarms were determined not to be a problem.
But Armstrong also noticed he and Aldrin were flying faster than expected across the lunar surface and were likely going to overshoot their landing site. As the Eagle passed 1,500 feet above the surface, Armstrong saw they were heading for a crater. He thought this might be a good option as it would have “more scientific value to be close to a large crater.” But the steep slope and big rocks did not provide a safe place to land.
As they continued to fly over areas covered with large rocks and boulders, Armstrong took over control of the Eagle and continued flying it manually. He was able to use his training from the LLTV to maneuver as they continued to descend to the surface. But all of the maneuvering was using up propellant. At 200 feet above the surface, Armstrong finally was able to find a place to land.
Aldrin: Eleven [feet per second] forward. Coming down nicely. Two hundred feet, four and a half down.
Armstrong: Gonna be right over that crater.
Aldrin: Five and a half down.
Armstrong: I got a good spot.
Aldrin: One hundred and sixty feet, six and a half down. Five and a half down, nine forward. You’re looking good.
As they passed 75 feet mission control in Houston determined the Eagle only had 60 seconds of fuel left. Armstrong says he wasn’t terribly concerned about the low fuel situation, “typically in the LLTV it wasn’t unusual to land with 15 seconds left of fuel.”
About 40 seconds later Armstrong made a final few maneuvers before announcing the landing was complete.
Armstrong: Shutdown.
Aldrin: Okay. Engine stop.
Houston: We copy you down, Eagle.
Armstrong: Houston, Tranquility Base here. The Eagle has landed.
It was later determined the Eagle had about 50 seconds of fuel left for maneuvering. Most remember Neil Armstrong as the first person to walk on the moon. As a test pilot, he often referred to being the first person to land a spacecraft on the moon, something he liked to point out was the more challenging part of the mission from his point of view.
After his historic descent down the ladder and making his “giant leap for mankind” Armstrong and Aldrin would spend just two hours and 36 minutes on the surface of the moon.
Read more at Wired Science
'Fresco Jesus' Attracts Hundreds of Visitors
It's been dubbed the "world's worst restoration", but a 102-year-old church painting of Christ that now resembles a pale monkey is drawing visitors by the hundreds to a sleepy Spanish town.
The northeastern town of Borja garnered global press attention after residents decried the well-meaning restoration efforts of Cecilia Gimenez, described as being in her 80s, who made a horribly botched attempt to restore a flaking oil painting of Christ wearing the crown of thorns.
The "restored" painting looks like a pale monkey's face surrounded by fur, with misshapen eyes and nose, and a crooked smudge for a mouth. Some media have called it the worst restoration in history.
On Saturday, hundreds of curious visitors queued up outside the Iglesia del Santuario de Misericordia church, where the image is painted on a column.
"The previous painting was also very pretty, but I really like this one," a woman who had traveled to the town said on public television.
Titled "Ecce Homo" (Behold the Man), the original was painted in 1910 by an artist called Elias Garcia Martinez.
Almost 18,000 people have now signed an online petition to halt the town's plan to return the painting to its pre-restoration glory.
Read more at Discovery News
The northeastern town of Borja garnered global press attention after residents decried the well-meaning restoration efforts of Cecilia Gimenez, described as being in her 80s, who made a horribly botched attempt to restore a flaking oil painting of Christ wearing the crown of thorns.
The "restored" painting looks like a pale monkey's face surrounded by fur, with misshapen eyes and nose, and a crooked smudge for a mouth. Some media have called it the worst restoration in history.
On Saturday, hundreds of curious visitors queued up outside the Iglesia del Santuario de Misericordia church, where the image is painted on a column.
"The previous painting was also very pretty, but I really like this one," a woman who had traveled to the town said on public television.
Titled "Ecce Homo" (Behold the Man), the original was painted in 1910 by an artist called Elias Garcia Martinez.
Almost 18,000 people have now signed an online petition to halt the town's plan to return the painting to its pre-restoration glory.
Read more at Discovery News
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