All ears for a new hearing aid
Few products are hated as much as hearing aids. The devices can squeal with feedback and overamplify background noises like the click of a turn signal or whir of a ceiling fan. They must be removed for showering or sleeping, and their batteries die frequently. Many users, out of exasperation, decide they’d rather live with hearing loss. But now scientists have come up with a different kind of hearing aid. While the device, called the Lyric, is being used in only 500 patients, it appears to have overcome many of the problems associated with traditional hearing aids — without the expense and uncertainty of surgery and anesthesia. The Lyric, made by InSound Medical of Newark, California, is hidden deep inside the ear canal, just 4 mm from the ear drum. While doctors for years have been implanting hearing devices in the middle ear, the Lyric is not an implant: it can be removed with a small magnet. It is worn 24 hours a day, and its batteries last one to four months. Because it sits so close to the ear drum, doctors say that it works more efficiently and that sounds are more natural because they don’t have to be amplified as much. When the Lyric’s battery dies, the entire device is replaced.
Advantage for algae species in changing oceans
Contrary to expectations, a microscopic plant that lives in oceans around the world may thrive in the changing ocean conditions of the coming decades, a team of scientists reported on Thursday. The main threat to many marine organisms is not global warming but ocean acidification, as carbon dioxide from the air dissolves into the water and turns into carbonic acid. Acid dissolves calcium carbonate in the skeletons of corals, for example; many scientists fear that acidification of the oceans will kill many, if not most, coral reefs by the end of the century.Similar concerns have been raised about coccolithophores, single-cell, carbonate-encased algae that are a major link in the ocean food chain. Earlier experiments with a species of coccolithophore, Emiliania huxleyi, had found that higher acidity hindered the algae’s ability to build the disks of carbonate that form its shell. In Friday’s issue of the journal Science, however, scientists led by M. Debora Iglesias-Rodríguez of the National Oceanography Center at the University of Southampton in England and Paul Halloran, a graduate student at the University of Oxford, reported that they found the exact opposite. The algae grew bigger in the more acidic water. The hopeful news for coccolithophores, however, does not overturn the gloomy predictions for corals or negate ocean acidification as an impending ecological disruption, Dr. Iglesias-Rodríguez said. Rather, she said, it points to how little data biologists currently have.
Your beverage bottle may have a toxic plastic ingredient
Canada could be the first country to make a health finding against bisphenol-a or BPA, which has been shown to disrupt the hormonal systems of animals. Then on Thursday, a report from the United States Department of Health and Human Services’ National Toxicology Programme endorsed a scientific panel’s finding that there was “some concern” about neural and behavioral changes in humans who consume BPA, which is widely used to make polycarbonate plastics, which are rigid and transparent like glass but very unlikely to shatter. Polycarbonates have many uses that pose no risk, like the cases of some iPod models. Because animal tests have shown that even small amounts of the chemical may cause changes in the body, however, researchers have focused on food- and drink-related applications of BPA, like beverage bottles. Some scientists question the significance to humans of studies indicating that even very small amounts of BPA. can induce changes in animals. There is also some dispute about how much of the chemical is released by plastics.
