Next week, German officials will flip the switch and turn on the world’s first coal-fired power plant to use carbon capture and storage technology, in which carbon dioxide is stripped out the plant’s emissions and pumped deep underground. This “clean coal” technology has been hailed as a possible way to get cheap energy without further contributing to global warming. The 30 megawatt Schwarze Pumpe power station, built and operated by Swedish power company Vattenfall, will produce power along with 10 tons of highly concentrated CO2 an hour. The CO2 will be loaded onto tankers and taken to a nearby gas field for sequestration [Earth2Tech].
The new Vattenfall plant is a relatively small pilot project intended to test the viability of carbon capture and storage; these technologies have yet to be deployed in full-scale commercial plants, which typically generate hundreds of megawatts of power. The technologies are currently expensive, partly because capturing and compressing carbon dioxide into liquid requires a good amount of energy. Critics also have questioned their effectiveness in keeping emissions sealed underground [GreenTech Media]. For all these reasons, some experts have wondered whether clean coal plants are a realistic option for large-scale energy production.
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Researchers have gotten an amazingly close look at the human brain’s methods of short-term memory formation and recollection. A new study has examined the activity of individual brain cells, and found that the same neurons that fire when a person gets their first look at something fire again when they recall it.
Scientists at the University of California, Los Angeles, (U.C.L.A.) showed 13 volunteers—epilepsy patients with therapeutic electrodes implanted in their brains—several five- to 10-second clips from videos such as The Simpsons. The researchers found that a small sample comprising some 50 neurons in the hippocampus and entorhinal cortex (memory centers in the brain) fired in distinctive repeatable patterns that differed for each clip [Scientific American]. A few minutes later, when researchers asked the volunteers to think back to the film clips and say what came to mind, the neurons fired in the same distinct patterns when they mentioned each clip.
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The last woolly mammoths, who tromped around the Siberian tundra before going extinct about 10,000 years ago, had North American roots, according to a new genetic analysis. Scientists studied DNA from the remains of 160 mammoths from across North America and Eurasia, and determined that the last remaining mammoths were migrants who had come to Siberia via the Bering land bridge, and somehow replaced the endemic population.
Researchers believe that mammoths originally spread from Asia to North America via the land bridge, creating two genetically distinct populations. Now, they’re hypothesizing that some members of the North American group eventually made a return trip and proved hardier survivors than the Siberian group. “For some reason the North American guys went back over and became kings,” says [lead researcher] Hendrik Poinar [New Scientist].
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Climate scientists have long predicted that global warming will melt polar ice sheets and cause sea levels to rise throughout the century, potentially swamping island nations and flooding low-lying coastal cities. But exactly how much ocean waters will rise has yet to be settled. Now, two studies have come out that at first appear to contradict each other, leading to clashing headlines like “An Inconvenient Truth” Exaggerated Sea Level Rise [Telegraph], and Sea Level Rise May Be Twice More Than Expected [Discovery News].
One study seems to downplay the risk of an extreme sea-level rise, while the other hypes it up. But a closer look reveals that the two studies actually bring researchers nearer to scientific consensus.
In the study published in Science [subscription required], researchers examined the hypothesis of a six-foot sea-level rise by 2100, and calculated how quickly the ice sheets in Greenland and Antarctica would have to melt into the oceans to produce this effect. Their calculations showed that the glaciers would have to essentially gallop towards the sea, which seems an unlikely outcome. In Greenland, the glaciers moving into the island’s calving fjords would have to increase their speed to 28.4 miles per year and sustain that speed until the end of the century [Telegraph]. These researchers believe the most plausible scenario is a sea-level rise of between two and six feet within this century. As their results have been compared to more radical estimates like the 20-foot rise mentioned in the documentary film An Inconvenient Truth, the findings are being greeted with relief.
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Researchers have discovered a stretch of “junk” DNA that may have contributed to humanity’s evolution of opposable thumbs. When genetically engineered into mice, the human DNA seems to activate genes in the budding wrist and thumb. Chimp and monkey versions, on the other hand, seem only capable of switching on genes in the developing shoulder [New Scientist].
In a new study, the research team combed through the vast regions of human DNA that do not contain code for making proteins. Formerly dissed as “junk DNA,” sections of these non-gene regions are now known to play a regulatory role, dialing down or cranking up the activity of actual genes [Science News]. Researchers first found a long sequence of DNA that had barely changed during the entire evolution of backboned creatures, and then zeroed in on a smaller stretch of code that had accumulated 16 changes since the ancestors of humans and chimpanzees split, about 6 million years ago.
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Bumblebees that have a close encounter with a dangerous predator are still cautious and wary the next day, even though their trepidation slows them down as they forage for food. In a new study, researchers used robot spiders to briefly trap the bees and study their behavior afterwards, and found that in the end, some of the bumblebees get a little paranoid…. “They’re behaving as if they’re starting to see ghosts,” [co-author Lars] Chittka says [Science News].
The researchers used small robots to imitate the look and behavior of crab spiders, which are one of the major predators of bumblebees. They lie in wait in flowers which the bees need to visit to collect nectar, and are difficult to spot because they can change colour to match their surroundings [New Scientist].
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Meat and milk from the offspring of cloned animals may already be part of the U.S. food supply, the Food and Drug Administration announced this week. While the cloning process is too expensive (about $20,000 per animal) to justify creating clones that will be turned into hamburgers, some ranchers have cloned animals with desirable traits, which they then breed the old-fashioned way to create offspring. Officials said it is impossible to differentiate between cloned animals, their offspring and conventionally bred animals, making it difficult to know if offspring are in the food supply [Reuters].
The use of cloned livestock–particularly cows, swine, and sheep–has been fiercely debated in the United States and Europe. In January, the FDA declared that cloned animals and their offspring were as safe to eat as conventionally bred animals; regulators still ask that food companies follow a voluntary moratorium on using cloned animals for food production, but no such moratorium exists for the clones’ natural offspring. Those offspring may have made it into the food supply, a U.S. Agriculture Department spokesman said, but “they would be a very limited number because of the very few number of clones that are out there and relatively few of those clones are at an age where they would be parenting” [Reuters].
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A new study of a chemical commonly used in plastic containers found that it causes damage to monkey’s brains, raising new concerns over the chemical’s possible effects on humans. The chemical, called bisphenol A or BPA, has been the source of controversy for months as government agencies and scientists have gone back and forth on whether the substance is a health threat. BPA has been in commercial use since the 1950s, and is found in baby bottles, water bottles, in the lining used for canned goods, and many other items.
In the latest study, the research team exposed monkeys to levels of bisphenol A deemed safe for humans by the Environmental Protection Agency and found that the chemical interfered with brain cell connections vital to memory, learning and mood. “Our findings suggest that exposure to low-dose BPA may have widespread effects on brain structure and function,” the authors wrote [Washington Post].
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The Environmental Protection Agency has vetoed a massive flood control project that was in the works for seven decades. The move – which puts the kibosh on the proposed Yazoo Pumps Project to reduce flooding between the Mississippi and Yazoo rivers – is only the 12th time the Environmental Protection Agency has used its authority to scrap a project under the Clean Water Act [Scientific American].
The EPA’s decision is being hailed as an environmental victory, as the plan called for massive pumps that would have drained water out of at least 67,000 acres of wetlands, irrevocably altering the ecosystem. The landscape of swamps, bayous, and cypress trees is vital to an extensive range of wildlife, including fish, migrating birds, and the endangered Louisiana black bear; the wetlands are valued not only by conservationists, but also by hunters and commercial fishermen.
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Researchers have gotten the closest look yet at the supermassive black hole that is believed to lurk in the center of the Milky Way, using radio telescopes to peer through the cosmic dust. Lead astronomer Sheperd Doeleman says: “One of the problems with looking at this particular source is that we have to look through our galaxy. It’s a blessing that it’s this close, but it’s a curse because it’s obscured by gas and dust” [SPACE.com].
Black holes can’t be directly observed, because their gravitational pull is so strong that nothing, not even visible light, can escape. To study our local gravitational monster, researchers homed in on Sagittarius A*, the bright radio-emitting body thought to mark the position of the black hole. Because Sagittarius A* is likely fueled by the black hole’s activity, a better look at the radio-emitting body can provide more details about the black hole [Science News].
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In the destructive heart of hurricane season, climate scientists have come out with some alarming news: the most powerful storms have gained wind strength over the past 25 years as a result of gradually warming ocean waters, and global warming is likely to continue that trend. It’s hardly welcome news, as Gulf Coast residents are still recovering from this week’s close call with Hurricane Gustav and Caribbean islanders are warily eyeing several new tropical storms gaining strength over the Atlantic.
The new study is likely to renew the debate over global warming’s effect on major storms: [T]here has been controversy about whether these hurricanes will get more intense and numerous, with many claiming the data are not good enough to discern a real trend upwards in recent years…. Today’s study, by Prof James Elsner of Florida State University, concludes that the strongest tropical cyclones - the general term for intense storms such as hurricanes and typhoons - are getting stronger, with the greatest increase recorded in the North Atlantic and northern Indian oceans [Telegraph].
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Small helicopters have learned to fly themselves through challenging aeronautic routines with an “apprenticeship” to an expert radio control pilot, researchers say. The clever robots were first steered through the maneuvers several times by the pilot while the helicopters’ computers recorded every movement; then the computers used an algorithm to determine the “ideal trajectory” that the pilot was aiming for on each loop or flip, and replicated those motions when they set off on their own into the wild blue yonder.
Researchers say the helicopters’ self-taught skills are particularly impressive due to difficulty of flying helicopters and their nature to always tend to an unstable state. “The helicopter doesn’t want to fly. It always wants to just tip over and crash,” said Garrett Oku, the pilot [TG Daily]. Because helicopters have to constantly adjust to changing wind currents, the inventors couldn’t simply program them to fly a set routine.
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By examining half a million tiny differences in the genomes of Europeans, researchers can determine with surprising accuracy where on the continent each person comes from, easily distinguishing the Irish from the English, for example. Two new studies reveal that our DNA contains a sort of global positioning system, which researchers can use to pinpoint where in the world both we and our relatives came from [ScienceNOW Daily News].
The findings surprised geneticists by showing that despite centuries of immigration and intermarriage throughout Europe, genetic differences between Europeans are almost entirely related to where they were born. This, however, does not mean that the citizens of each European nation represent miniature races. “The genetic diversity in Europe is very low. There isn’t really much,” says Manfred Kayser [New Scientist], author of one of the studies.
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A team of architects and environmental engineers has proposed covering swaths of the Sahara with vast “salt water greenhouses” powered by solar power arrays, in a plan they call the Sahara Forest Project. Charlie Paton, inventor of the salt water greenhouse, says the combined technologies could transform patches of the desert from arid wastelands into lush expanses that produce a bounty of fruits and vegetables for local people.
The plan is no doubt ambitious and unproved at this scale, but Paton says he has built demonstration greenhouses on the Spanish island Tenerife, as well as in Abu Dhabi and Oman; he says there is further interest in funding demonstration projects from across the Middle East, including UAE, Oman, Bahrain, Qatar and Kuwait. The cost is not as astronomical as one would think, and is estimated at approximately $118 million for a 20 hectare [50 acre] site of greenhouses and a 10MW concentrated solar power farm [Red Herring]. Paton is working with Exploration Architecture, a company that worked on the world’s largest greenhouse in England’s Eden Project.
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Older men have an increased risk of fathering children who eventually develop bipolar disorder, according to new research. It’s the latest study to refute the earlier theory that men could father children into their old age with no ill effects; other recent studies have linked older fathers to an increased risk of miscarriages, and to children with schizophrenia or autism.
The theory linking paternal age with an offspring’s health rests on the genetics of aging sperm. Spontaneous mutations can accumulate in the genes of a man’s sperm cells as he ages. These cells divide as many as 660 times by the time a man reaches 40, by some estimates. Each division increases the risk of acquiring a harmful mutation from erroneous gene copying, the theory holds [Science News]. Women are born with their full complement of eggs already in place in the ovaries, and therefore don’t have to worry about increased genetic errors as they age.
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