It may soon get easier to fix a broken hearts. Researchers have taken the next step towards heart patches that could one day help people recover from heart attacks.
Scientists have been experimenting with different ways to integrate new stem cells or cardiac cells with damaged heart tissue, but it’s a difficult task: the patches must be flexible enough to contract with the beating heart yet strong enough to hold up under the repetitive motion, and blood vessels must be coaxed through the new tissue to prevent the implanted cells from dying. In a new study published in Proceedings of the National Academy of Sciences researchers report that growing the patch in the belly of a rat brought better results when the patch was later moved to the rat’s heart.
Scientists have long wondered what exactly is killing bees in hives afflicted by colony collapse disorder (CCD), and now they may have found a clue. Bees in collapsing hives showed evidence of damaged ribosomes, which are crucial to protein production, according to a study published in the journal Proceedings of the National Academy of Science. The researchers suggest that an onslaught of viruses may be responsible for the cellular damage.
The findings suggest that CCD, which has been blamed on everything from viruses to fungi to pesticides, may be linked to problems with protein production that could make bees more susceptible to these threats. “If your ribosome is compromised, then you can’t respond to pesticides, you can’t respond to fungal infections or bacteria or inadequate nutrition because the ribosome is central to the survival of any organism. You need proteins to survive” [AP], said lead researcher May Berenbaum.
Physicists in Washington State and Louisiana recently spent two years hunting for the mysterious gravitational waves first predicted by Einstein, but detected nothing: zilch, zero, nada, nary a ripple. But that “null result” is itself of great value, researchers say, because it tells them where to look for the waves next. The findings are a nice reminder that scientific progress isn’t always about the dramatic discovery; it’s often a long, careful process of testing hypotheses, analyzing results, and heading back to the drawing board.
Einstein’s theory of general relativity states that every time mass accelerates — even when you rise up out of your chair — the curvature of space-time changes, and ripples are produced. However, the gravitational waves produced by one person are so small as to be negligible. The waves produced by large masses, though, such as the collision of two black holes or a large supernova explosion, could be large enough to be detected [SPACE.com].
Beyond those large disturbances, the universe is thought to be filled with small disturbances left over from the rapid period of expansion that followed the Big Bang, in a phenomenon known as the stochastic (meaning randomly distributed) gravitational wave background. If the expansion of the newborn universe had produced strong gravity waves, the physicists working at the two Laser Interferometer Gravitational-wave Observatory (LIGO) centers would have detected them. Since they found nothing, researchers have determined that smaller waves were produced, which they’ll need more sensitive instruments to detect. Says study coauthor Vuk Mandic: “We now know a bit more about parameters that describe the evolution of the universe when it was less than one minute old” [Sky & Telescope].
Up to half of the U.S. population could contract swine flu this upcoming flu season, killing up to 90,000 people and hospitalizing 1.8 million, according to a report released by the President’s Council of Advisors on Science and Technology.
Americans lack immunity to the swine flu, which gives the virus the potential to infect more people than the seasonal flu generally does. And although many people who contract the disease might not show symptoms, and most would not be hospitalized, the pandemic would put a strain on the U.S. health-care system … because those patients could occupy between 50% and 100% of available intensive-care beds at the peak of the epidemic in affected regions, while ICU units normally operate close to capacity. Seasonal flu normally causes about 200,000 hospitalizations a year [The Wall Street Journal].
Long gone are the days when a “robotic movement” meant something jerky, awkward, and stiff: The new robo-fish that have just been unveiled by engineers at the Massachusetts Institute of Technology swim through the water with sinuous grace. The flexible fish move naturally, as the motor in the middle initiates a wave that moves along the body and propels it forward. Real fish move in a similar fashion by contracting muscles on either side of their bodies [CNET]. The robo-fish are the descendants of Charlie the Robotuna, a large robot created at MIT in the 1990s that consisted of almost 3,000 parts. The new fish measure less than a foot long and use only 10 parts; researchers say the simple, durable fish are cheap to produce and hard to damage. To manufacture each robot, a single motor is placed in a fish-shaped mold before a liquid polymer is poured in and allowed to solidify. The continuous polymer casing prevents water from seeping in and damaging the motor, says Pablo Alvarado, an engineer who helped design the fish. “These materials are very resilient,” he said. “Water can’t do much to them and they can survive very high temperatures. Unless another fish eats them, they could go on and on” [Wired.com].
During both work hours and leisure time, a growing number of people have become extravagant multitaskers, flitting between Web browsing, texting, emailing, and maybe even throwing in some old-fashioned television or print media for good measure. But a surprising new study has found that those who multitask the most are far worse at it than those people who focus on fewer tasks simultaneously. Says study coauthor Clifford Nass: “The huge finding is, the more media people use the worse they are at using any media. We were totally shocked” [AP].
The researchers compared high- and low-multitaskers on a variety of psychological tests, according to the study published in the Proceedings of the National Academy of Sciences. They found that the high-multitaskers were worse at ignoring irrelevant information, worse at organizing information, and took more time to switch between tasks. That final finding particularly surprised the researchers, considering the need to switch from one thing to another in multitasking. “They couldn’t help thinking about the task they weren’t doing,” lead author Eyal Ophir said [AP].
In a series of dramatic (if blurry) photographs, scientists have captured a rare type of lightning known as a “gigantic jet.” These jets strike up from the thunderclouds instead of down from them towards the earth, according to findings published in Nature Geoscience.
Catching the phenomenon on film has boosted scientists’ understanding of the lightning. “These are not just sparks that come out of the thunderstorm and travel upward and tickle the upper atmosphere. They actually deliver to the upper atmosphere as much electric charge as the very strong lightning strokes to ground” [BBC], says lead author Steven Cummer. Capturing gigantic jets as they occur is difficult because they occur infrequently, and because scientists don’t yet know which types of storms promote their formation. Cummer got his shot by luck. He had his cameras trained on the clouds brewed by the 2008 tropical storm Cristobal, hoping to spot another form of electrical discharge, when the jet blasted upward, reaching 40 miles into the upper atmosphere.
80beats: A Fleet of Professional Storm Chasers Will Study Tornado Genesis
80beats: Lightning May Have Created Special Food for Earth’s Early Microbes
DISCOVER: Juicing Up the Atmosphere has more on these strange jets
DISCOVER: Where Lightning Strikes
Image: Steven Cummer
Studies have shown that heterosexual adult men reduce their risk of HIV by 50 percent by being circumcised. “We have a significant H.I.V. epidemic in this country, and we really need to look carefully at any potential intervention that could be another tool in the toolbox we use to address the epidemic…. What we’ve heard from our consultants is that there would be a benefit for infants from infant circumcision, and that the benefits outweigh the risks” [The New York Times], says CDC epidemiologist Peter Kilmarx.
On the other hand, circumcision has not been shown to reduce HIV risk among men who have sex with men–the U.S. demographic with the highest risk of contracting the virus. And the American Academy of Pediatrics does not currently endorse routine circumcision, as it doesn’t consider the procedure essential to a baby’s well-being. Finally, nearly four-fifths of American men are circumcised, so it’s not clear whether a policy recommending circumcision would have much impact.
80beats: Study: Circumcision of HIV-Positive Men Doesn’t Protect Women
80beats: Male Circumcision Cuts Risk of HIV, Herpes, and HPV Transmission
DISCOVER: Male Circumcision: A New Defense Against HIV
DISCOVER: Finally! A Nearly Foolproof Circumcision
Image: flickr/ Topdog1
Although scientists may not have come close to cataloging all the different kinds of life on the planet, genetics pioneer Craig Venter is pressing ahead with his plans to create biology version 2.0. Venter is at the forefront of the new field of synthetic biology, in which scientists try to create all new organisms out of their component genetic parts: “We’re moving from reading the genetic code to writing it” [Pittsburgh Post-Gazette], Venter has said. Now, he and his colleagues have taken the next step towards synthetic life.
In a study published in Science, the researchers explain how they took the genome from the bacterium Mycoplasma mycoides and transferred it to a yeast cell, where established genetic engineering techniques allow for easier tinkering. After altering the genome in several key ways, they transplanted it into the hollowed out shell of a different bacterial species, Mycoplasma capricolum. The breakthrough came when the altered genome “booted up” and began instructing its host bacterium to produce colonies of M. mycoides.
That success will help researchers overcome a stubborn obstacle that has prevented the creation of a made-from-scratch life form. Last year, Venter’s team created a synthetic bacterial genome by stitching together pieces of synthesized DNA. To build a synthetic organism, however, researchers will have to transplant that synthetic genome into a cell and have it successfully reboot the cell. But that last step has proved problematic. The synthetic genome was assembled in yeast, which means it lacked some of the molecular markings characteristic of bacteria. Researchers discovered that without those markings, the host bacterium viewed the transplanted genome as a foreign invader and destroyed it [Technology Review]. In the new study, the researchers added chemical markings called methyl tags to the M. mycoides genome while it was in the yeast cell, permitting the genome to sneak past the host bacterium’s defenses.
In the first experiment linking cognitive ability to reproductive success, researchers found that the male bowerbirds with the best problem-solving capabilities also mated the most often, according to a study published in the journal Animal Behaviour.
The Australian bowerbird is known for its elaborate courtship behavior. During breeding season, males build a special platform, or bower, on the forest floor to lure females, and they decorate it with rare objects such as blue feathers and shiny bits of glass. They accompany this with varied vocalizations, hopping, and tail-bobbing [ScienceNOW Daily News]. To evaluate which males had the best problem-solving abilities, scientists placed a red object in the birds’ bowers–a color the birds disdain. In one experiment, three red objects were placed in the bower and covered by clear plastic that the bird had to take off in order to remove the noxious items. In the next, the red object was securely nailed to the nest, so the only way to make it less visible was to cover it with leaves and twigs.