Dewayne Dedmon's Leap Of Faith: Discouraged for Religious Reasons from Playing Basketball
|1:59:36 AM, Friday, November 11, 2011|
"Thou wilt show me the path of life.
Dieter Horton first caught sight of the skinny kid with the long arms one afternoon in April 2008. The boy was sitting in the first row of the bleachers in the small gym at Antelope Valley College, waiting silently, his knees together. Only when he stood up, 30 minutes later, did Horton realize just how tall he was. At least 6'8", Horton thought. Then he looked closer: Who the hell is this kid?
After all, AVC is located in Lancaster, Calif., in the heart of the Antelope Valley, only an hour's drive north of Los Angeles over the San Gabriel Mountains but in a world of its own. If there was a teenager within a nose of 6'6" in the valley, Horton could tell you his home address, his girlfriend's name and what he liked on his pizza. In 11 years as a junior college basketball coach in California, Horton had won a state title, sent nearly 20 kids to Division I schools and set a state juco record by finishing 37--0 at Fullerton College in 2005--06. Young, ambitious and handsome in a clean-cut way, Horton scouted so relentlessly that his phys-ed students had grown accustomed to his teaching with a cellphone pressed to his ear. Yet here was a towering kid unfamiliar to the coach from local high schools or the AAU circuit or even city rec leagues.
When Horton finished talking with one of his players, the boy walked over. He wore an enormous pair of beat-up hightops, ratty shorts and a white T-shirt so large it looked like a muumuu. He hunched over, as if trying to shrink to standard proportions. "Coach," he said, "my name is Dewayne Dedmon. I want to play basketball."
Instantly Horton recognized the name. For years stories had floated around the valley about a tall kid who wasn't allowed to play basketball, but the coach had never believed them. He heard lots of stories. Most came from the kids themselves. Every year dozens of cocky teenagers approached Horton and assured him they'd score 20 a game if only he'd give them a uniform and the rock. To weed out the dreamers and boasters, he told them, "Come back next week." Only one in 10 ever did.
"O.K., Dewayne Dedmon, how about we see what you got," Horton said. "Show up next Tuesday at 3 p.m., and we'll work you out."
Dedmon nodded. "Yes, sir," he said. "I'll see you then."
Within a few days, Horton had forgotten all about him.
Gail Lewis was so proud she felt like crying. She stared at the letters on the notepaper stuck to the wall and read along. She knew the line, from Proverbs. Then she looked down at her nine-year-old son, sitting on his bed in their sparsely furnished three-bedroom apartment in Lancaster. Here he was, only halfway grown up and already disciplining himself..."
How the Potato Changed the World
|1:46:32 AM, Friday, November 11, 2011|
"When potato plants bloom, they send up five-lobed flowers that spangle fields like fat purple stars. By some accounts, Marie Antoinette liked the blossoms so much that she put them in her hair. Her husband, Louis XVI, put one in his buttonhole, inspiring a brief vogue in which the French aristocracy swanned around with potato plants on their clothes. The flowers were part of an attempt to persuade French farmers to plant and French diners to eat this strange new species.
Today the potato is the fifth most important crop worldwide, after wheat, corn, rice and sugar cane. But in the 18th century the tuber was a startling novelty, frightening to some, bewildering to others—part of a global ecological convulsion set off by Christopher Columbus.
About 250 million years ago, the world consisted of a single giant landmass now known as Pangaea. Geological forces broke Pangaea apart, creating the continents and hemispheres familiar today. Over the eons, the separate corners of the earth developed wildly different suites of plants and animals. Columbus’ voyages reknit the seams of Pangaea, to borrow a phrase from Alfred W. Crosby, the historian who first described this process. In what Crosby called the Columbian Exchange, the world’s long-separate ecosystems abruptly collided and mixed in a biological bedlam that underlies much of the history we learn in school. The potato flower in Louis XVI’s buttonhole, a species that had crossed the Atlantic from Peru, was both an emblem of the Columbian Exchange and one of its most important aspects.
Compared with grains, tubers are inherently more productive. If the head of a wheat or rice plant grows too big, the plant will fall over, with fatal results. Growing underground, tubers are not limited by the rest of the plant. In 2008 a Lebanese farmer dug up a potato that weighed nearly 25 pounds. It was bigger than his head.
Many researchers believe that the potato’s arrival in northern Europe spelled an end to famine there. (Corn, another American crop, played a similar but smaller role in southern Europe.) More than that, as the historian William H. McNeill has argued, the potato led to empire: “By feeding rapidly growing populations, [it] permitted a handful of European nations to assert dominion over most of the world between 1750 and 1950.” The potato, in other words, fueled the rise of the West.
Equally important, the European and North American adoption of the potato set the template for modern agriculture—the so-called agro-industrial complex. Not only did the Columbian Exchange carry the potato across the Atlantic, it also brought the world’s first intensive fertilizer: Peruvian guano. And when potatoes fell to the attack of another import, the Colorado potato beetle, panicked farmers turned to the first artificial pesticide: a form of arsenic. Competition to produce ever-more-potent arsenic blends launched the modern pesticide industry. In the 1940s and 1950s, improved crops, high-intensity fertilizers and chemical pesticides created the Green Revolution, the explosion of agricultural productivity that transformed farms from Illinois to Indonesia—and set off a political argument about the food supply that grows more intense by the day..."
Poland's Mysterious Crooked Forest
|1:31:06 AM, Friday, November 11, 2011|
"In a tiny corner of western Poland a forest of about 400 pine trees grow with a 90 degree bend at the base of their trunks - all bent northward. Surrounded by a larger forest of straight growing pine trees this collection of curved trees, or "Crooked Forest," is a mystery.
Planted around 1930, the trees managed to grow for seven to 10 years before getting held down, in what is understood to have been human mechanical intervention. Though why exactly the original tree farmers wanted so many crooked trees is unknown."
Russia Races to Rescue Mars Probe From Earth Orbit
|1:19:59 AM, Friday, November 11, 2011|
"MOSCOW (AP) — A Russian spacecraft on its way to Mars with 12 tons of toxic fuel is stuck circling the wrong planet: ours. And it could come crashing back to Earth in a couple of weeks if engineers can't coax it back on track.
Space experts were hopeful Wednesday that the space probe's silent engines can be fired to send it off to Mars. If not, it will plummet to Earth. But most U.S. space debris experts think the fuel on board would explode harmlessly in the upper atmosphere and never reach the ground.
The launch mishap was the latest in a series of recent Russian failures that have raised concerns about the condition of the country's space industries.
The unmanned $170 million Phobos-Ground craft successfully got into orbit, propelled off the ground by a Zenit-2 booster rocket just after midnight Moscow time Wednesday (2016 GMT Tuesday) from the Baikonur cosmodrome in Kazakhstan. After separating from its booster, 11 minutes later, it was supposed to fire its engines twice and head to Mars.
Neither engine fired. So the spacecraft couldn't leave Earth's orbit, flying between 129 and 212 miles above Earth. And that orbit is already deteriorating, according to American satellite tracking.
The Federal Space Agency said the probe's orbit and its power sources could allow it to circle the Earth for about two weeks. That jibes with calculations made by NASA.
"From the orbits we're seeing from the U.S. Space Surveillance Network, it's going to be a couple weeks before it comes in," NASA chief debris scientist Nicholas Johnson said Wednesday afternoon. "It's not going to be that immediate."
The craft was aiming to get ground samples from Phobos, one of Mars' two moons, and return them in a daring expedition hailed by eager scientists, who said it may include bits of Mars that may have been trapped on its moon.
Federal Space Agency chief Vladimir Popovkin said the system that keeps the spacecraft pointed in the right direction may have failed. The Russian rescue effort was being hampered by a limited earth-to-space communications network. Even before the problem, flight controllers were forced to ask people in South America to scan the sky to see if the engines on the spacecraft fired.
Amateur astronomers were the first to spot the trouble when they detected the craft was stuck in an Earth orbit.
As time went on Wednesday, experts in the United States became more confident that the Russians could still get the probe going, just a day or two later than planned. There were no sightings of an explosion or partial rocket firings, which are good signs, said James Oberg, a NASA veteran who has written books on the Russian space program and who now works as a space consultant.
"I am growing more confident as we realize that the vehicle is healthy; it didn't blow up," Oberg said late Wednesday afternoon. "They have a chance of doing a Hubble repair, an Apollo 13, snatching victory out of jaws of defeat kind of thing."
The hope is that this is just a software problem that can be fixed and uploaded to the probe, said Bruce Betts, program director of the Planetary Society in the United States, a group that has a $500,000 experiment on board.
"There's a major problem, but it might be recoverable," Betts said. "The game's not over yet."
The spacecraft is 13.2 metric tons (14.6 tons). Russian data shows that most of that weight — about 11 metric tons (12 tons) — is fuel, NASA's Johnson said..."
Why Are There So Many Colors of Poisonous Frogs?
|1:04:59 AM, Friday, November 11, 2011|
"Hopping around in the Peruvian jungle, near the border with Brazil, is a menagerie of tiny poison dart frogs. Their wealth of colors and patterns—some have golden heads atop white-swirled bodies, others wear full-torso tattoos of black and neon-yellow stripes—act as the world's worst advertisement to predators: Don't eat me, I'm toxic. But why have so many designs evolved when a single one might do?
Evolutionary biologist Mathieu Chouteau of the University of Montreal in Canada ventured into the rainforest to find out. He was on the trail of Ranitomeya imitator, a single species of poison dart frog that comes in about 10 different patterns. That variability should be confusing for predators, he says, because the warnings are supposed to be a message to them, and it would make more sense to give them only one design to keep track of.
To figure out what was going on, Chouteau enlisted his girlfriend's help to make 3600 models of frogs, each 18 millimeters long. "It was, like, at least a month of working full-time," he says. They pressed black clay into frog-shaped molds and painted each one in one of two patterns: yellow striped or reticulated, like a giraffe, with green lines. They also made brown frogs as a nontoxic-looking control. Then Chouteau packed the frogs in his carryon baggage and flew to Peru.
The models represent the frogs that live in two different sites: one in the Amazonian lowland and one in a valley at about 500 meters above sea level. The two sites are separated by a high ridge. In one very long day at each site, Chouteau set out 900 of the frogs on leaves along narrow trails used by locals to hunt in the forest. For the next 3 days, he went back and checked them to see whether the soft clay recorded evidence of attacks by birds.
Birds mostly avoided the model that looked like the local frog, but they attacked the model that looked like the frog from the other site, Chouteau reports in the December issue of The American Naturalist. In the high valley, the land of the reticulated frogs, only 7.2% of the model frogs with the reticulated pattern were attacked, whereas 14.2% of the brown models and 26.6% of the yellow-striped models were attacked. The pattern was roughly reversed at the other site.
And that helps explain the diversity of frogs in the rainforest, Chouteau says. Different frog patterns rule at different sites, and birds keep these designs going by weeding out any frogs that deviate from the norm.
"This study shows quite nicely how, once you've got the diversity, it's stabilized," says Chris Jiggins, an evolutionary biologist at the University of Cambridge in the United Kingdom. But where the diversity comes from, he says, is "a bit of an outstanding question." It's possible that frogs with a particular pattern are somehow better suited to the environment where they live, but he thinks the differences more likely arise because of drift. Random changes in pattern get established and then keep evolving, making the frogs distinctive. "What's actually kind of surprising is the birds are really going for these frogs," he says. "You'd think, these frogs are so nasty, you wouldn't go anywhere near a poison dart frog." Maybe the rainforest is so diverse that it's always worth trying something, even something brightly colored."
Russian 'Grave Robber Made Dolls From Girls' Corpses'
|12:50:55 AM, Friday, November 11, 2011|
"A suspected grave robber in the central Russian city of Nizhny Novgorod is said by police to have made 29 life-size dolls from mummified female corpses.
Local historian and cemetery explorer Anatoly Moskvin, 45, was arrested last week by police investigating a spate of grave desecrations in the area.
The brightly dressed dolls, their faces and limbs covered in cloth, were found in his flat and garage, police said.
It was not clear whether each doll contained a set of human remains.
Police are now trying to establish the identity of the mummified remains.
They said they had been investigating "numerous" grave desecrations in cemeteries in and around Nizhny Novgorod since last year.
Video released by police on their website shows the dolls seated on shelves or sofas, in small rooms stacked with books and papers.
No actual bones are apparent in the footage and some of the faces are covered by masks.
Officials said the remains belonged mainly to girls or young women, and they had been dressed in clothes taken from corpses.
Also found in Mr Moskvin's flat were photographs and nameplates taken from headstones as well as instructions for making dolls and maps of cemeteries in the region, a police statement said.
Shoes found in the flat matched footprints found in cemeteries, it added.
Some Russian media are reporting that Muslim graves were singled out in the robberies.
According to the police statement, Mr Moskvin is "well-known in academic circles" having studied Celtic culture at a leading Russian university, and is the author of many books and academic works.
He is described in Russian media reports as a "necropolist", or cemetery expert.
Police did not say how he had been arrested and Russian newspapers report variously that he was caught with a bag of bones or that detectives grew suspicious when they consulted him, as a cemetery expert, about the desecrations.
Alexei Yesin, editor of a local newspaper to which Mr Moskvin contributed, told the Associated Press news agency he was a loner who had "certain quirks" but said he had given no indication that he was up to anything so strange.
"I saw no signs of that while working with him," Mr Yesin said.
In a 2007 interview with the newspaper Nizhegorodsky Rabochy, Mr Moskvin said he had begun wandering through cemeteries when still a schoolboy..."
Tardigrades: Water Bears in Space
|12:05:34 AM, Wednesday, November 09, 2011|
"In 2007, a little known creature called a tardigrade became the first animal to survive exposure to space.
It prevailed over sub-zero temperatures, unrelenting solar winds and an oxygen-deprived space vacuum.
On Monday, this microscopic cosmonaut has once again hitched a ride into space on the Nasa shuttle Endeavour.
Its mission: to help scientists understand more about how this so-called "hardiest animal on Earth" can survive for short periods off it.
Tardigrades join other microscopic organisms selected to be part of a project into extreme survival.
Project Biokis is sponsored by the Italian Space Agency and will investigate the impact of short-duration spaceflight on a number of microscopic organisms.
The project will use seven experiments to investigate how spaceflight affects organisms on a molecular level.
The team will be using molecular biology to evaluate any changes in the organisms' genetic information, as well as investigating how cells physically adapt to cope with extreme dehydration, caused by the space vacuum, and damage caused by cosmic radiation.
One of these experiments, the Tardkiss experiment, will expose colonies of tardigrade to different levels of ionising radiation, determined using an instrument called a dosimeter, at different points during the spaceflight mission.
The results from Tardkiss will enable researchers to determine how radiation dosage effects the way cells work.
Tardigrades are of particular interest following the 2007 European Space Agency (Esa) Foton-M3 mission, during which their ability to survive space conditions was discovered.
Tardigrades are microscopic animals more commonly known by their non-scientific name, the water bear.
Their stocky bodies and gait have all the hallmarks of a bear. But this isn't a typical bear encounter.
These bears are less than 1mm long and are found in the sea, in fresh water and on land.
Genetic studies have shown that they originally lived in freshwater environments before adapting to colonise the land, seeking out moist habitats such as soil, mosses, leaf litter and lichen.
Tardigrades earned the "hardiest animal on earth" tag having evolved elaborate dormancy strategies that allow them to shut down all but the essential biological processes when conditions are not conducive to supporting life.
Professor Roberto Guidetti from the University of Modena and Reggio Emilia believes their ability to suspend life and withstand freezing and desiccation may explain why they can survive in space.
"Tardigrades can be found all over the world from the Arctic to the Antarctic, from high mountains to deserts, in urban areas and backyard gardens," he explained.
"In terrestrial environments, they always require at least a film of water surrounding their bodies to perform activities necessary for life."
But if these conditions change, tardigrades are capable of entering an extreme form of resting called cryptobiosis.
In this state, they are capable of withstanding freezing, a process called cryobiosis, and desiccation, a process called anhydrobiosis..."
-- Not exactly news, but unless you keep up with stuff like this, you likely have not heard of it.
Cloud-Powered Facial Recognition Is Terrifying
|5:43:16 PM, Friday, November 04, 2011|
""I never forget a face," goes the Marx Brothers one-liner, "but in your case, I'll be glad to make an exception."
Unlike Groucho Marx, unfortunately, the cloud never forgets. That's the logic behind a new application developed by Carnegie Mellon University's Heinz College that's designed to take a photograph of a total stranger and, using the facial recognition software PittPatt, track down their real identity in a matter of minutes. Facial recognition isn't that new -- the rudimentary technology has been around since the late 1960s -- but this system is faster, more efficient, and more thorough than any other system ever used. Why? Because it's powered by the cloud.
The logic of the new application is based on a series of studies designed to test the integration between facial recognition technology and the wealth of data accessible in the cloud (by which we basically mean the Internet). Facial recognition's law enforcement uses -- to identify criminals out of a surveillance video tape, say -- have always been limited by the criminal databases available for reference. When Florida deployed Viisage facial recognition software in January 2001 to search for potential troublemakers and terrorists in attendance at Super Bowl XXXV, police in Tampa Bay were only able to extract useful information on 19 people with minor criminal records who already existed in any database they had access to. But the Internet was a much smaller place in 2001; Google was in its infancy, and the sheer volume of data available in a simple search simply didn't exist.
Often, the problems with facial recognition are rooted in the need for greater processing power, human and machine. After revelers rioted in the streets of Vancouver following the Canucks' defeat in the Stanley Cup, Vancouver police received nearly 1,600 hours of footage from bystanders furious with their fellow citizens; the department was woefully inequipped to handle the sudden influx of data, anticipating that it would take nearly two years to analyze all the information. Vancouver's Digital Multimedia Evidence Processing Lab was able to cut the processing time to a mere three weeks with a relatively small 20-workstation lab.
With Carnegie Mellon's cloud-centric new mobile app, the process of matching a casual snapshot with a person's online identity takes less than a minute. Tools like PittPatt and other cloud-based facial recognition services rely on finding publicly available pictures of you online, whether it's a profile image for social networks like Facebook and Google Plus or from something more official from a company website or a college athletic portrait. In their most recent round of facial recognition studies, researchers at Carnegie Mellon were able to not only match unidentified profile photos from a dating website (where the vast majority of users operate pseudonymously) with positively identified Facebook photos, but also match pedestrians on a North American college campus with their online identities.
The repercussions of these studies go far beyond putting a name with a face; researchers Alessandro Acquisti, Ralph Gross, and Fred Stutzman anticipate that such technology represents a leap forward in the convergence of offline and online data and an advancement of the "augmented reality" of complementary lives. With the use of publicly available Web 2.0 data, the researchers can potentially go from a snapshot to a Social Security number in a matter of minutes:
We use the term augmented reality in a slightly extended sense, to refer to the merging of online and offline data that new technologies make possible. If an individual's face in the street can be identified using a face recognizer and identified images from social network sites such as Facebook or LinkedIn, then it becomes possible not just to identify that individual, but also to infer additional, and more sensitive, information about her, once her name has been (probabilistically) inferred.
In our third experiment, as a proof-of-concept, we predicted the interests and Social Security numbers of some of the participants in the second experiment. We did so by combining face recognition with the algorithms we developed in 2009 to predict SSNs from public data. SSNs were nothing more than one example of what is possible to predict about a person: conceptually, the goal of Experiment 3 was to show that it is possible to start from an anonymous face in the street, and end up with very sensitive information about that person, in a process of data "accretion." In the context of our experiment, it is this blending of online and offline data - made possible by the convergence of face recognition, social networks, data mining, and cloud computing - that we refer to as augmented reality.
Naturally, the development of such software inspires understandably Orwellian concerns. Jason Mick at DailyTech notes that PittPatt started as a Carnegie Mellon University research project, which spun off into a company post 9/11. "At the time, U.S. intelligence was obsessed with using advanced facial recognition to identify terrorists," writes Mick. "So the Defense Advanced Research Projects Agency (DARPA) poured millions into PittPatt." While Google purchased the company in July, the potential for such intrusive technology to be used against law-abiding citizens is cause for concern..."
The Navy Deploys An Underwater Roomba To Keep Its Fleet Shipshape
|5:05:22 PM, Friday, November 04, 2011|
"The Hull Bug, inspired by hermit crabs, will swim alongside warships and keep their hulls sparkling clean.
Barnacles. They may look innocuous when you see them on the undersides of breaching whales, but they increase drag on the underside of a ship significantly, reducing its speed by up to 10 percent and increasing fuel consumption by up to 40 percent.
For the Navy, which spends a lot of time and fuel sailing ships, this is a problem. In fact, the Navy is forced to spend $1 billion a year on extra fuel and the cleaning of its ships.
So it's developing an autonomous robot inspired by the grooming behavior of sea creatures (PDF), and it's currently undergoing tests by the Office of Naval Research for deployment in 2015 across the U.S. Navy's fleet. The robot, which is something like an underwater Roomba, is described as a "robotic hull biomimetic underwater grooming," or Hull Bug.
In general, "fouling" of ships affects the world's entire fleet of ships, and is a major drag-- literally!--on the fuel efficiency of vessels of every size. Traditional approaches to keeping barnacles and other "biofilms," or collections of living gunk, off ships and submarines involve toxic paints laced with large amounts of copper. Not only do these paints pollute the harbors where ships spend most of their time, they're a headache to dispose of when dry-docked vessels are sandblasted every decade.
Hull Bug represents a completely different approach to keeping ships free of crud: It's not terribly powerful, but the idea is that it would be so easy to use, it could be deployed almost continuously, to gently sweep biofilms and baby barnacles off the underside of a ship. (The alternative are less-frequent cleanings carried out by divers equipped with spinning brushes, an expensive and difficult proposition.)
Hull Bug is inspired by the "grooming" behavior common to just about every crustacean on the planet. Hermit crabs even have a special pair of legs devoted to just this purpose.
The Hull Bug is relatively small: it's less than three feet long, weighs 50 pounds, and uses a simple bulldozer attachment to keep a hull clear of material. But its most clever features are how it navigates and adheres to the ship..."
Ant Jaws Break Speed Record, Propel Insects Into Air, Biologists Find
|5:02:18 PM, Friday, November 04, 2011|
"21 August 2006
BERKELEY – A species of ant native to Central and South America is entering the annals of extreme animal movement, boasting jaws arguably more impressive than such noteworthy contenders as the great white shark and the spotted hyena.
Biologists clocked the speed at which the trap-jaw ant, Odontomachus bauri, closes its mandibles at 35 to 64 meters per second, or 78 to 145 miles per hour - an action they say is the fastest self-powered predatory strike in the animal kingdom. The average duration of a strike was a mere 0.13 milliseconds, or 2,300 times faster than the blink of an eye.
A research team led by Sheila Patek, assistant professor of integrative biology at the University of California, Berkeley, calculated the kinematics of the trap-jaw ant's mandible strikes with the help of advances in high-speed videography. The researchers published their results in the Aug. 21 issue of the Proceedings of the National Academy of Sciences.
They found that the jaws, used to capture prey and to defend the ant from harm, accelerate at 100,000 times the force of gravity, with each jaw generating forces exceeding 300 times the insect's body weight. The ants in this study had body masses ranging from 12.1 to 14.9 milligrams.
"You'd think the relevant number is the mandible closing speed, but it's actually the acceleration that is most impressive," said Patek. "The acceleration is huge relative to the tiny mass of the mandibles. The mandibles are operating in the outer known limits in biology in terms of speed and acceleration."
Patek acknowledged that falcons can dive as fast as 300 miles per hour, but that the raptors must start from very high altitudes and get a boost from the force of gravity to reach those speeds. In comparison, animals such as trap-jaw ants and mantis shrimp (which formerly held the record for swiftest strike in the animal world) utilize energy stored within their own bodies. The mandibles of the trap-jaw ant, for instance, are held cocked by a pair of huge, contracting muscles in the head. The muscles are sprung when their corresponding latches, each on a shield-like plate called the clypeus, are triggered.
"Having a latch system is critical in obtaining the explosive speeds," said Patek. "In general, muscles aren't good at generating fast movements. If a person were to throw an arrow, it wouldn't get very far. But by using a crossbow, elastic energy is stored in the bow, and a latch releases the stored energy almost instantaneously. As a result, the arrow shoots out very fast and goes much farther. That's exactly what really fast organisms are doing."
It's no wonder, then, that O. bauri ants can launch themselves into the air with a mere snap of their jaws, achieving heights up to 8.3 centimeters and horizontal distances up to 39.6 centimeters. That roughly translates, for a 5-foot-6-inch tall human, into a height of 44 feet and a horizontal distance of 132 feet, an aerial trajectory likely to be the envy of circus acrobats and Olympic athletes.
The jump's trajectory depends on the purpose of the mandible's strike. When the ant, either alone or in a group, approaches and strikes a large intruder with its jaws, it is simultaneously catapulted away from the trespasser, perhaps leaving behind a crippled victim in the process. In these so-called "bouncer defense" maneuvers, the trap-jaw ants clear, on average, 22.3 centimeters horizontally, but only 0.8 to 5.7 centimeters vertically.
In comparison, when the ant needs to escape quickly from an intruder, it strikes its jaws against the ground to fling itself into the air. In these "escape jumps," the ant is jettisoned to heights of 6.1 to 8.3 centimeters, but just 3.1 centimeters horizontally.
Escape jumps also yield a faster initial spin rate, 63 revolutions per second, compared to the relatively slow spin rate of 36 revolutions per second for bouncer defense jumps.
Study co-author Andrew Suarez, assistant professor of entomology at the University of Illinois at Urbana-Champaign, noted that when the ants jump to escape from harm, they are airborne from 0.22 to 0.27 seconds, often long enough to keep them away from a lizard's tongue, which takes 0.11 to 0.28 seconds to strike.
The researchers suggest that the "popcorn effect" of multiple ants jumping at once may also serve to help them escape by confusing potential predators. Suarez, along with study co-author Brian Fisher, associate curator and chair of entomology at the California Academy of Sciences, witnessed this jumping frenzy first-hand when they were in Costa Rica collecting the worker ants for this study.
The researchers said the difference in aerial trajectories may be more a function of the angle at which an ant's mandibles hit their target rather than an intentional maneuver, although that is something they intend to investigate further..."
-- Old, but an interesting read nonetheless.
Analysis Reveals Malaria, Other Diseases as Ancient, Adaptive and Persistent Foes
|11:22:54 PM, Wednesday, November 02, 2011|
"One of the most comprehensive analyses yet done of the ancient history of insect-borne disease concludes for the first time that malaria is not only native to the New World, but it has been present long before humans existed and has evolved through birds and monkeys.
The findings, presented in a recent issue of American Entomologist by researchers from Oregon State University, are based on the study of insect specimens preserved in amber.
The study outlines the evolution of several human diseases, including malaria, leishmaniasis and trypanosomiasis. It makes clear that these pathogens have existed for at least 100 million years, and suggests that efforts to conquer them will be an uphill battle against such formidable and adaptive foes.
"Amber tells us that these diseases have been here for many millions of years, have co-evolved with their hosts and move readily from one species to another," said George Poinar, Jr., a professor of zoology at OSU and one of the world's leading experts on the study of fossils in this semi-precious stone.
"Malaria is one of the greatest insect-borne killers in human history, and more than one million people a year are still dying from it," Poinar said. "But the evolutionary record suggests it can easily change its protein coat in response to vertebrate immune reactions. That's why it's always becoming resistant to drugs, and efforts to create vaccines will be very difficult."
Insects preserved for tens of millions of years are offering new clues to the ancient history of these diseases. Blood-feeding vectors trapped eons ago in oozing tree sap reveal in near-perfect detail stages of vertebrate pathogens they were carrying when they became entombed.
"Most people think of malaria as a tropical disease, which today it primarily is," Poinar said. "But historically it occurred in many parts of the world, including temperate zones."
"As recently as 1935 there were 900,000 cases of malaria in the United States," he said. "Near Portland, Ore., malaria almost wiped out some local Indian tribes in the 1830s, and the mosquitoes that carried it are still prevalent there. In the 1600s it hindered colonization from Massachusetts to Georgia. And there are 137 million people right now living in areas of risk in the Americas..."
Chinese Spacecraft Dock in Orbit
|11:14:55 PM, Wednesday, November 02, 2011|
"China has joined two space vehicles together in orbit for the first time.
The unmanned Shenzhou 8 craft, launched earlier this week, made contact with the Tiangong-1 space lab at 1729 GMT. The union occurred over China itself.
Being able to dock two space vehicles together is a necessary capability for China if it wants to start building a space station towards the decade's end.
Although no astronauts were in the Shenzhou craft this time, future missions will carry people.
Tuesday's procedure (Beijing time 0029, Thursday) took place at an altitude of about 340km. It was automated but overseen on the ground at the Beijing Aerospace Flight Control Centre.
The vehicles used radar and optical sensors to compute their proximity to each other and guide their final approach and contact. A video feed from orbit showed the final moments of the vehicles coming together.
Shenzhou 8 was the active craft in the docking. It fired its thrusters to push its front end towards the docking port of Tiangong-1. Once the vehicles' docking rings had made a good capture, 12 hooks were deployed to fix the craft in place. Protruding pins made electrical connections.
From first contact to confirmation of a seal took about 10 minutes.
Shenzhou 8 and Tiangong-1 will spend two weeks circling the globe together before Shenzhou 8 heads back to Earth.
"After a joint flight of about 12 days, they will separate," explained Prof Yang Yuguang from the China Aerospace, Science and Industry Corporation.
"Then the Shenzhou 8 will draw back to about 140m. After that they will perform a second docking. Then they will have a flight of two days. Then they will be separated to about 5km; this will be a safe distance for both vehicles. Then the re-entry procedure will be performed by the Shenzhou 8 spaceship," he told state broadcaster China Central Television (CCTV).
The return capsule will land by parachute to allow experiments carried into orbit to be recovered for analysis. The German space agency (DLR) has supplied an experimental box containing fish, plants, worms, bacteria and even human cancer cells for a series of biological studies.
"This is a great moment for Chinese space activities," observed DLR chairman Prof Jan Woerner.
"This co-operation between China and Germany is called the Simbox; and it's a box in which we have small apparatus to investigate the cells of plants and animals, to see their behaviour under zero gravity conditions.
"It's a really sophisticated experiment and I hope that the results will help also on Earth to learn more about the behaviour of cells in cancer and the immune system...""
New Material for Air Cleaner Filters that Captures Flu Viruses
|11:04:06 PM, Wednesday, November 02, 2011|
"With flu season just around the corner, scientists are reporting development of a new material for the fiber in face masks, air conditioning filters and air cleaning filters that captures influenza viruses before they can get into people's eyes, noses and mouths and cause infection. The report on the fiber appears in ACS' journal Biomacromolecules.
Xuebing Li, Peixing Wu and colleagues explain that in an average year, influenza kills almost 300,000 people and sickens millions more worldwide. The constant emergence of new strains of virus that shrug off vaccines and anti-influenza medications has led to an urgent need for new ways of battling this modern-day scourge. So Li, Wu and colleagues sought a new approach, using a substance termed chitosan made from ground shrimp shells.
The scientists combined chitosan with substances that the flu virus attaches to in order to infect cells. They found that this new version of chitosan ideal for attaching to fibers of face masks and air filters was highly effective in capturing flu virus. The material could become an important addition to vaccinations, anti-influenza medications, and other measures in battling flu, they suggest.
The high transmissibility and genetic variability of the influenza virus have made the design of effective approaches to control the infection particularly challenging. The virus surface hemagglutinin (HA) protein is responsible for the viral attachment to the host cell surface via the binding with its glycoligands, such as sialyllactose (SL), and thereby is an attractive target for antiviral designs. Herein we present the facile construction and development of two SL-incorporated chitosan-based materials, either as a water-soluble polymer or as a functional fiber, to demonstrate their abilities for viral adhesion inhibition and decontamination. The syntheses were accomplished by grafting a lactoside bearing an aldehyde-functionalized aglycone to the amino groups of chitosan or chitosan fiber followed by the enzymatic sialylation with sialyltransferase. The obtained water-soluble SL–chitosan conjugate bound HA with high affinity and inhibited effectively the viral attachment to host erythrocytes. Moreover, the SL-functionalized chitosan fiber efficiently removed the virus from an aqueous medium. The results collectively demonstrate that these potential new materials may function as the virus adsorbents for prevention and control of influenza. Importantly, these materials represent an appealing approach for presenting a protein ligand on a chitosan backbone, which is a versatile molecular platform for biofunctionalization and, thereby, can be used for not only antiviral designs, but also extensive medical development such as diagnosis and drug delivery."
Tiny 'Saber-Toothed Squirrel' Found
|10:50:42 PM, Wednesday, November 02, 2011|
"As suggested in the "Ice Age" movies, some crazy-looking creatures roamed the planet millions of years ago. But there is a large gap in the fossil record from about 60 million to 120 million years ago when it comes to mammals in South America. Where were they, and what did they look like?
Scientists have now discovered a quirky little creature from this time period, as reported in the journal Nature. It's called Cronopio dentiacutus, and it resembles a mouse-sized squirrel with proportionally long teeth, although technically speaking it is neither a squirrel nor saber-toothed.
"The reality of exploration and research can sometimes be as strange as fiction that we see in the movies," said Guillermo Rougier, lead author of the study and professor at the University of Louisville.
The extinct mammal, which lived 94 million years ago, belongs to the lineage that has given rise to the marsupials and placental mammals that we know today. It's related to all living mammals, including humans in a remote way. It has been extinct for about 60 million years. Rougier and colleagues examined its unique skull.
"It was a lot more primitive than we are with regard to the way in which the skull was put together; the teeth were very primitive," Rougier said. "The skull is about an inch long."
Scientists believe was Cronopio dentiacutus was an insectivore, which is common for small animals today. Their teeth seem to be specialized for cutting and crushing; the large canines of Cronopio dentiacutus could puncture through small insects. To give you some perspective on the size of these canines, imagine if one of your front teeth came down below your chin, Rougier said.
Coronpio dentiacutus lived at the same time as small carnivorous dinosaurs, terrestrial crocodiles and snakes with legs. It inhabited the flood plains of Argentina that is now a desert area in Patagonia, where people live on subsistence farming.
Most mammals were very small, like Coronpio dentiacutus, at that time, said Rougier. It wasn't until big dinosaurs went extinct that mammals grew to be as large as cats and small dogs.
"These were the tiny little guys that would squirrel in between the toes of the dinosaurs trying not to get stepped on.""
Fruit Fly Intestine May Hold Secret to the Fountain of Youth
|10:43:08 PM, Wednesday, November 02, 2011|
"One of the few reliable ways to extend an organism's lifespan, be it a fruit fly or a mouse, is to restrict calorie intake. Now, a new study in fruit flies is helping to explain why such minimal diets are linked to longevity and offering clues to the effects of aging on stem cell behavior.
Scientists at the Salk Institute for Biological Studies and their collaborators found that tweaking a gene known as PGC-1, which is also found in human DNA, in the intestinal stem cells of fruit flies delayed the aging of their intestine and extended their lifespan by as much as 50 percent.
"Fruit flies and humans have a lot more in common than most people think," says Leanne Jones, an associate professor in Salk's Laboratory of Genetics and a lead scientist on the project. "There is a tremendous amount of similarity between a human small intestine and the fruit fly intestine."
The findings of the study, which was a collaboration between researchers at the Salk Institute for Biological Studies and the University of California, Los Angeles, were published online in Cell Metabolism.
Scientists have long known that calorie restriction, the practice of limiting daily food intake, can extend the healthy lifespan of a range of animals. In some studies, animals on restricted diets lived more than twice as long on average as those on non-restricted diets.
While little is known about the biological mechanisms underlying this phenomenon, studies have shown that the cells of calorie-restricted animals have greater numbers of energy-generating structures known as mitochondria. In mammals and flies, the PCG-1 gene regulates the number of these cellular power plants, which convert sugars and fats from food into the energy for cellular functions.
This chain of connections between the mitochondria and longevity inspired Jones and her colleague to investigate what happens when the PCG-1 gene is forced into overdrive. To do this, they used genetic engineering techniques to boost the activity of the fruit fly equivalent of the PCG-1 gene. The flies (known as Drosophila melanogaster) have a short lifespan, allowing the scientists to study aging and longevity in ways that aren't as feasible in longer-lived organisms such as mice or human.
The researchers found that boosting the activity of dPGC-1, the fruit fly version of the gene, resulted in greater numbers of mitochondria and more energy-production in flies - the same phenomenon seen in organisms on calorie restricted diets. When the activity of the gene was accelerated in stem and progenitor cells of the intestine, which serve to replenish intestinal tissues, these cellular changes correspond with better health and longer lifespan. The flies lived between 20 and 50 percent longer, depending on the method and extent to which the activity of the gene was altered.
"Their intestines were beautiful," says Christopher L. Koehler, a doctoral-student at University of California San Diego who conducts research in Jones' laboratory. "The flies with the modified gene activity were much more active and robust than the other flies."
Part of the reason for this might be that boosting the fruit fly version of PCG-1 stimulates the stem cells that replenish the intestinal tissues, keeping the flies' intestines healthier. The findings suggest that the fruit fly version of PCG-1 can act as a biological dial for slowing the aging process and might serve as a target for drugs or other therapies to put the breaks on aging and age-related diseases.
"Slowing the aging of a single, important organ - in this case the intestine - could have a dramatic effect on overall health and longevity," Jones says. "In a disease that affects multiple tissues, for instance, you might focus on keeping one organ healthy, and to do that you might be able to utilize PGC-1.""
HOME Older Posts »