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Environmental monitoring is often expensive, cumbersome, and time-intensive. Equipment that can run quick and easy tests for pollutants like pesticides in our food are almost nonexistent. However, researchers in Canada are working on a new biomonitoring technique using treated paper on a stick that can quickly identify trace amounts of pesticides in your chicken soup, or your first early morning cup of joe [Technology Review]. Could these dipsticks lead to DIY pollution monitoring one day? That may still be far off, but this technology could give researchers a reliable and cheap way to get a better picture of what pollutants—even at trace amounts—are in the environment, and how they interact with our bodies.

In the study, published in the journal Analytical Chemistry, the researchers describe a new paper-based test strip that changes color shades depending on the amount of pesticide present. In laboratory studies using food and beverage samples intentionally contaminated with common pesticides, the test strips accurately identified minute amounts of pesticides. The test strips, which produced results in less than 5 minutes, could be particularly useful in developing countries or remote areas that may lack access to expensive testing equipment and electricity, they note [R&D Magazine]. If the dipsticks pan out, restaurant customers may one day have more to complain about than a stray hair in their soup.

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Image: ACS

Proceedings of the National Academy of Sciences, November 3
Two studies in PNAS focused on the wildlife and landscape of East Africa. In the first, researchers looked back in history to Kenya’s infamous man-eating lions, which reportedly devoured 135 railroad laborers in 1898. The two lions were eventually shot, killed, stuffed, and shipped to Chicago’s Field Museum for display–which allowed researchers to analyze samples of the lions’ bones and fur. By comparing the isotopes present in the man-eating lions to those found in other lions, humans, wildebeest, and buffalo, the researchers could precisely determine the lions’ diet. The results brought the body count down considerably: The scientists estimate that one of the lions ate 24 people, while the other gobbled up 11. The second study looked ahead, and predicted that Mount Kilimanjaro, the highest peak in Africa, could lose its distinctive ice cap by 2022 due to global warming.

Journal of the American Medical Association, November 4
A new study of hospitalizations in California due to swine flu has highlighted a neglected risk factor: obesity. In the study group of patients whose weight was known, researchers found that 25 percent of the people were morbidly obese, although less than 5 percent of the U.S. population falls into that category. Researchers also found that 58 percent of these hospitalized patients were obese–in the population as a whole, about 34 percent of people are obese. The increased risks come partially from health problems associated with obesity, like heart disease, lung ailments, and diabetes. But physiological factors may also be to blame: The lungs of obese patients are squeezed by the abdomen pressing upward on the diaphragm.

Nature, November 5
A new astronomy study has solved a mystery that began brewing in 1680, when Britain’s first Astronomer Royal spotted a supernova in the constellation Cassiopeia. Supernova typically collapse into a super-dense object like a black hole or a neutron star, but for decades astronomers have looked for such an object at the center of the supernova remnant, to no avail. Now, a new examination suggests that there is indeed a baby neutron star there, but it escaped detection because it’s swaddled in an unusual atmosphere of carbon gas. Further studies of the 330-year-old star will give researchers insight into how such stars mature. Another study brings us from the macro to the micro, with an investigation into the evolution of bacteria. Researchers forced bacteria to evolve in constantly changing conditions, so that natural selection couldn’t produce microbes that were ideally suited to a single environment. Instead, researchers proved that the bacteria hedged their bets by evolving into a strain that could form several different shapes from the same genetic material. The will to survive: It’s an amazing thing.

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Babies pick up their parents’ accents while still in the womb, according to a new study. After studying the crying patterns of 30 French and 30 German newborns, researchers concluded that the French newborns cried with a rising “accent” while the German babies’ cries had a falling inflection [BBC News]. The researchers believe that by mimicking their mothers’ inflections, the babies are attempting to form an early bond with their mothers.

Scientists already knew that a baby in the womb can memorize sounds from the outside world, and is particularly sensitive to the melodies of her mother’s language.  But the new research showed an “extremely early” impact of native language and confirmed that babies’ cries are their first proper attempts to communicate specifically with their mothers [Reuters]. The data support the idea that crying seeds language development for infants, according to the scientists, who published their research in the journal Current Biology.

To hear the different between German and French crying babies for yourself, click here to listen.

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Image: flickr / chalky lives

News that an Iowa cat has been diagnosed with swine flu has sparked a new round of concerns, as pet-owners worry both that their furry companions could get sick, and that their pets could pass the virus on to other humans. The 13-year-old, mixed-breed cat showed the symptoms of lethargy, sneezing and coughing typical to sick cats [ABC News]. The veterinarians who treated him say that several people in the cat’s home had been experiencing flu-like symptoms, and lab work confirmed that the feline had the H1N1 virus.

Happily, the cat is expected to make a full recovery. But both vets and public health officials are rushing to reassure the public that one sick cat probably does not indicate a coming crisis. While it’s possible that more cats will be diagnosed with the swine flu, vets point out that the virus was circulating for more than six months before the first cat case was discovered, indicating that the virus probably doesn’t jump from species to species very easily. Doctors also note that there’s very little chance that a cat will spread the virus to humans: Even when inter-species transmissions do occur, the H1N1 virus seems more likely to move from humans to animals, rather than the other way around [HealthDay News].

There have been no reported cases of dogs catching the virus, but there is one type of pet that is known to be vulnerable. Ferrets are generally susceptible to the seasonal flu, and the AP reported Wednesday that H1N1 infection has been confirmed in two ferrets, one in Nebraska and the other in Oregon. “Not only can they be infected with the flu but they are clearly able to transmit the flu back to people,” Treanor said [HealthDay News]. But the bottom line appears to be: Unless you’re a ferret-owner, you probably have nothing to worry about.

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Image: flickr / theogeo

Researchers may have taken a step towards curing the rare, inherited brain disease made famous by the movie Lorenzo’s Oil–and also towards ushering a new era of gene therapy. To help two young boys suffering from the disease, researchers tried an experimental treatment using a deactivated version of the HIV virus. The virus delivered working copies of a gene to stem cells from the patients’ bone marrows. The HIV virus, stripped of genetic material that makes it toxic, integrates permanently into the DNA of cells it enters, scientists said. That means the modified gene remains in the blood-forming stem cells for the life of the patient [Bloomberg].

Adrenoleukodystrophy, or ALD, is a progressive disease characterized by the gradual destruction of the myelin sheaths that insulate neurons and nerves, allowing electrical signals to be transmitted through them. The disease is caused by a genetic defect, which prevents cells in the bone marrow from producing a crucial protein necessary for the formation of the myelin sheaths. Typically, children with ALD are given bone marrow transplants to provide them with healthy blood-forming stem cells, but in the two cases described in the study, no matching donors could be found.

In the experimental treatment, described in a paper published in Science, researchers took blood stem cells from the patients’ bone marrow and used the new vector system to genetically alter them by inserting a working copy of the … gene. The modified cells were then put back into the patients [Reuters].

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When 3-year-old Mark Blinder developed pain in his right arm, doctors diagnosed him with Ewing’s sarcoma, a rare bone tumor. Chemotherapy wasn’t working and radiation would have destroyed the growth plates in his bones. So instead of amputating the arm, doctors tried an experimental approach–implanting an artificial, expandable bone made of titanium and cobalt chrome, designed specifically for Mark. The bone, produced by the company Biomet Inc., is small enough to fit inside the 3-year-old’s arm, but should be sturdy enough to last his entire life.  Most artificial bones are used to replace only part of a bone, so they are glued securely to remaining bone. In Mark’s case, the entire humerus was being removed, so the prosthetic had to be attached to soft tissue [Los Angeles Times].

To install the bone, doctors first had to remove the tumor by carving out the fat around it, a process one of the doctor’s likened to carving out a peach pit without ever touching the pit. The surgery was a success but Mark, who is now 4 years old, underwent chemotherapy as a precaution. Mark is gradually relearning how to use his arm. He’s moving his wrist and fingers, can pick up small objects, and is receiving physiotherapy to rebuild strength and flexibility in the elbow and shoulder. He won’t ever regain full function in those joints, but he is using the arm more each day, his mother said [Los Angeles Times]. He will have to undergo three or four minor surgeries over the years so doctors can extend the prosthetic bone as he grows–but since the only other option open to Mark was amputating his arm completely, he probably won’t complain.

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Image: iStockphoto

A supernova that was observed in 1680 by Britain’s first Astronomer Royal, John Flamsteed, has been revealed to have produced a strange little neutron star that will give astronomers insight into how such stars are born and mature. The remains of the supernova, known as Cassiopeia A, have been something of a mystery to astronomers. Supernovae usually leave behind an extremely dense object such as a black hole or neutron star. But for decades no such object was seen at the centre of Cassiopeia A [Nature News]. Now new observations suggest that the 330-year-old neutron star escaped detection because of its odd atmosphere.

Instead of resembling more mature neutron stars, which are surrounded by hydrogen, this baby star is blanketed in carbon gas – a discovery that could provide important new insights into the evolution of neutron stars [Physics World]. The new study, published in Nature, suggests that the star is still extremely hot in the aftermath of the supernova–about 2 billion degrees Fahrenheit. This overheated condition caused a nuclear fusion reaction on the star’s surface that converts all the hydrogen and helium into carbon gas, researchers say. As time goes on, and as the star cools, the researchers think the surface fusion reaction will stop and the star will develop a more traditional hydrogen atmosphere.

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Image: NASA / CXC / Southampton / W. Ho / M. Weiss

A laser-powered robot took a climb up a cable in the Mohave Desert in Wednesday, and pushed ahead the sci-fi inspired notion of a space elevator capable of lifting astronauts, cargo, and even tourists up into orbit. The robot, built by LaserMotive of Seattle, whizzed up 2,953 feet (nearly 1 kilometer) in about four minutes, which qualifies the team for at least $900,000 of the $2 million in prizes offered in the NASA-backed Space Elevator Games.

Theorized in the 1960s and then popularized by Arthur C. Clarke’s 1979 novel “The Fountains of Paradise,” space elevators are envisioned as a way to gain access to space without the risk and expense of rockets. Instead, electrically powered vehicles would run up and down a cable anchored to a ground structure and extending thousands of miles up to a mass in geosynchronous orbit — the kind of orbit communications satellites are placed in to stay over a fixed spot on the Earth [AP].

The LaserMotive vehicle that climbed up the cable (held by a hovering helicopter) was powered by a system that resembles an upside-down solar power mechanism. Laser beams on the ground were fired up at the ascending craft and hit its photovoltaic cells–like those used in solar panels–in a process known as “power beaming.” LaserMotive will have a chance to improve its vehicle’s speed at another trial today, and other teams will also be vying for prizes.

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Image: Space Elevator Games. The LaserMotive vehicle gets weighed in.

Great white sharks, much like humans, tend to stick to familiar turf, according to new research. Also like a lot of people, they like to hang out along the coastal waters of California. Sharks tagged with acoustic devices often spent up to 107 days at four key sites along the central and northern California coast where seals and sea lions are abundant: Southeast Farallon Island, Tomales Point, Año Nuevo Island and Point Reyes [LiveScience]. A few of the fearsome predators were tracked as far inland as the Golden Gate Bridge, apparently in search of snacks, say the researchers. The study, the largest and most detailed study of North American great white sharks, provides evidence contrary to the popular notion of great white sharks swimming aimlessly in the ocean.

The sharks under study divided most of their time between three locations: Northern California, Hawaii, and an area that the researchers called the white shark café, a spot in the open ocean about halfway between the Baja Peninsula and the Hawaiian Islands. Exactly what goes on at the café is still unknown–although researchers suspect it may be a hot spot for mating. Lead researcher Salvador Jorgensen explains that male white sharks “converge in a very specific area of the cafe,” Jorgensen said, while female sharks move in and out of the area. “It adds a little more evidence to the argument that this could be an important reproductive area” [Washington Post].

The scientists tracked the snaggly toothed predators between 2000 and 2008 from the Bay Area to San Diego, Hawaii and back as the sharks followed a route that was carried out with surprising precision and under a strict time frame [San Francisco Chronicle]. These great whites have been isolated from other great white sharks near Australia and South Africa for so long that they are now genetically distinct. The study was published in the journal Proceedings of the Royal Society B.

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Image: flickr / hermanusbackpackers

Curvis Bickham spent eight months in prison for a triple-homicide because a police dog confused his scent with that of the killer. Now Bickham and others who spent months in jail after dogs linked their scents to evidence from crimes they did not commit are filing a lawsuit claiming Texas authorities falsely arrested and imprisoned them, their attorney said Tuesday [AP]. In a scent lineup, dogs sniff items found at a crime scene, and then sniff jars swabbed with the suspects’ scents and the scents of others not involved in the crime. When the dogs link crime scene and suspect, that evidence is often relied on heavily in court by the prosecution. Alaska, Florida, New York and Texas all use scent lineups to link suspects to crimes.

Dogs are used all the time to fight crime—from sniffing out bombs and drugs to locating dead bodies. However, scent lineups have critics barking. They say the lineups are poorly controlled, and argue that avoiding cross-contamination is basically impossible. The main target of the current lawsuit is Fort Bend County Deputy Keith Pikett—whose home-trained bloodhounds identified the suspects. A 2004 F.B.I. report warned that dog scent work “should not be used as primary evidence,” but only to corroborate other evidence. In several of the cases that were based on Deputy Pikett’s dogs, however, the scent lineups appear to have provided the primary evidence, even when contradictory evidence was readily available [The New York Times]. Deputy Pikett, by his own estimation, has conducted thousands of scent lineups.

The three men who filed the lawsuit against Deputy Pickett were all eventually set free after contradictory evidence proved their innocence. The Innocence Project of Texas, a legal defense organization … released a report last month that excoriated dog scent lineups as a “junk science injustice” [The New York Times]. Dog scent lineups bring to mind another high profile forensic science debate in Texas that many believe led to the execution of an innocent man. Now that the science behind dog scent lineups is coming under the same scrutiny, one can’t help but wonder if scent lineups might have led to a similar outcome.

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Image: flickr / contadini

The quest to find a second Earth–a potentially habitable planet that’s about the size of our home, but that lies in a distant solar system–has hit a snag. The Kepler space telescope was expected to be well on its way to detecting Earth-sized exoplanets by now, but an electronic glitch is slowing it down. The delays are caused by noisy amplifiers in the telescope’s electronics. The team is racing to fix the issue by changing the way data from the telescope is processed, but the delay could mean that ground-based observers now have the upper hand in the race to be the first to spot an Earth twin [Nature News].

Kepler, which was launched in March, uses the transit method to detect exoplanets; it’s watching a patch of 100,000 stars in hopes of detecting the brief dimming of a star’s light, which indicates that a planet has passed in front of the star. Kepler focuses light onto 42 light-detecting chips, called CCDs, each of which monitors stars in a different part of the telescope’s field of view. Each CCD is split into two for the purposes of sending data back to Earth, for a total of 84 data channels. Three of these channels are plagued by electronic noise that makes stars in their field of view appear to flicker – “like it’s changing its brightness at a rapid rate”, says Kepler chief scientist William Borucki [New Scientist]. That’s awkward, since the artificial flickers could obscure the real dimming that occurs during a planet’s transit.

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In 2005, the earth cracked open in Ethiopia. Two volcanic eruptions shook the desert, and a 35-mile-long rift opened in the land, measuring 20 feet wide in some places. Now a new study adds weight to the argument that the opening of this crack marks the first step in the formation of a new sea that may eventually separate East Africa from the rest of the continent. Says lead researcher Atalay Ayele: “The ocean’s formation is happening slowly, likely to take a few million years. It will stretch from the Afar depression (straddling Ethiopia, Eritrea and Djibouti) down to Mozambique” [ABC News].

The study, to be published in the journal Geophysical Research Letters, explains that the seismic movements observed in Ethiopia are very similar to the changes wrought by faults and fissures on the seafloor, where the processes that move tectonic plates usually begin.

Seismic data from 2005 shows that the rift opened in a matter of days. Dabbahu, a volcano at the northern end of the rift, erupted first, then magma pushed up through the middle of the rift area and began “unzipping” the rift in both directions, the researchers explained in a statement today. “We know that seafloor ridges are created by a similar intrusion of magma into a rift, but we never knew that a huge length of the ridge could break open at once like this” [LiveScience], says study coauthor Cindy Ebinger.

The active volcanic region in Ethiopia’s Afar desert sits at the boundary of the African and Arabian tectonic plates, which have been gradually spreading apart for millions years; the new study shows that large-scale seismic events can speed up that process. The gradual separation has already formed the 186-mile Afar depression and the Red Sea. The thinking is that the Red Sea will eventually pour into the new sea in a million years or so [LiveScience].

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Image: University of Rochester

If you’ve caught an episode of COPS lately, then you’ve probably noticed that so-called less-lethal weapons have caught on with police departments across the country as a way to force unruly suspects into compliance. Tasers, which delivers an electrical current to the suspect via two dart-like electrodes, are often the weapon of choice. Now, the Pentagon wants to use beefed up Taser technology on the battlefield.

The puny little electrodes that the police weapons use just won’t do for the military. That’s why the U.S. Department of Defense has been developing a long-range electric shock device that fires from a 40-millimeter grenade launcher and can subdue an enemy from just under 200 feet away. The new Human Electro-Muscular Incapacitation (HEMI) projectile is being developed for the Pentagon by Taser International under a $2.5 million contract and should be ready for prototype testing some time after the new year [Popular Science]. HEMI’s range is three times longer than Taser International’s XREP shotgun-style projectile, which has generated controversy because of concerns that the projectile could be deadly in untrained hands.

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When NASA’s Messenger space probe swung past Mercury on September 29, it snapped this picture of the innermost planet’s barren and strange landscape. The $446 million probe’s third flyby brought it within 142 miles (228 km) of Mercury’s surface to cover more uncharted terrain, leaving 98 percent of the planet now mapped [SPACE.com].

The images taken and the data recorded during the flyby are the last that will be acquired until Messenger finally slips into orbit around Mercury in 2011. The probe has now completed about three-quarters of its swooping 4.9-billion-mile journey that will eventually bring it into orbit.

Researcher Brett Denevi explains that this enhanced color shot shows a bright area surrounding an irregular depression, with steep sides and an odd shape, “all of which are hallmarks of something like a volcanic vent,” Denevi said [SPACE.com]. The double-ring basin in the center of the photo measures about 180 miles in diameter. It appears to be a relatively young impact crater–researchers believe it formed about 1 billion years ago–and the smooth stuff on the crater floor may be even younger volcanic material.

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Image: NASA

Cancer treatment in the future could have dramatically reduced side effects if new nanotechnology research proves useful. Heat-sensitive nanoparticles might be able to deliver drugs to a targeted location in the body—to a tumor, say—and release them on cue, a sought-after goal of biomedical research.

One research team has developed nanoparticle cages that can be stuffed with tiny amounts of drugs that are only released on demand. These “nanocages” are cubes of gold, with sides about 50-billionths of a meter long and holes at each corner. They are easily made, using silver particles as a mold, and then coated with strands of a smart polymer. The polymer strands are normally extended and bushy and cover the holes in the cube. But when heated the strands collapse, leaving the holes open and allowing the drug inside to escape [The New York Times]. The researchers say they can engineer the nanocages to stick to tumors.

Doctors could release the packaged drugs whenever they want, just by zapping the cages inside the patient’s body with near-infrared light. Near-infrared wavelengths are not greatly absorbed by body tissues, so light from a near-infrared laser could penetrate a couple of inches inside the body, but they are absorbed by gold [The New York Times]. Researchers could design the cages to fall apart at just a few degrees above normal body temperature, so they only spill their contents where the heat is applied; they could also alter the drug’s rate of release by adjusting the laser’s intensity. The technology, described in the journal Nature Materials, could help cut down on the side effects of today’s treatments which are often caused by toxic drugs coursing through the body.

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Image: Younan Xia, Washington University in St. Louis