Ears Wide Open

Mosquito Wins Ig Nobel Prize - The "Mosquito," a device that emits a high-frequency tone audible only to the relatively fresh ears of those under 25, is one of ten recipients of this year's Ig Nobel award, which recognizes the quirkier side of serious scientific endeavour, according to Marc Abrahams, the Harvard professor behind them, honouring "achievements that first make people laugh, and then make them think". The Mosquito was developed by a security company in Wales as a way of dispersing loitering teens. A second Ig Nobel went to US scientists for their work on the mystery of why fingernails being dragged down a blackboard produces an excruciating sound. The study, entitled Psychoacoustics of Chilling Sound, by a team led by D. Lynn Halpern at Northwestern University in Chicago, found the noise topped a list of annoying sounds and revealed that it remains "deeply unpleasant" even if the high-pitched squeals are digitally silenced. Source: The Guardian, 10/6/06 [READ ARTICLE]

Listening for Cancer Cells - Researchers at the University of Missouri-Columbia can now detect the spread of skin cancer cells through the blood by literally listening to their sound. The unprecedented, minimally invasive technique causes melanoma cells to emit noise, and could let oncologists spot early signs of metastases -- as few as 10 cancer cells in a blood sample -- before they even settle in other organs. The results of the successful experimental tests appear in the Oct. 15 issue of the journal Optics Letters, published by the Optical Society of America.
The team's method, called photoacoustic detection, combines laser techniques from optics and ultrasound techniques from acoustics, using a laser to make cells vibrate and then picking up the characteristic sound of melanoma cells. The microscopic granules of melanin contained in the cancer cells absorb the energy bursts from the blue-laser light, going through rapid cycles of expanding as they heat up and shrinking as they cool down. These sudden changes generate ultrasonic sounds which propagate in the solution like tiny tsunamis. Source: EurekAlert, 10/16/06 [READ PRESS RELEASE]

Manatees May "Hear" Through Sensitive Hairs Covering Their Bodies - New research has revealed that manatees have highly sensitive hairs that are used much like whiskers, providing an exquisite sense of touch. More intriguing, the neural system processing these sensations is linked to their auditory system. It is possible that manatees use these hairs to help them hear low frequency sounds, which their auditory system is not tuned to. Recent research has shown that manatee hearing is most sensitive to high frequencies, 16-18kHz, which has called into question protection measures based on making boats slow down (since manatees may, in fact, better hear the high whine of faster-moving boats). A new study found that manatees could detect sounds below 1kHz, and new research is underway to confirm whether the hairs are the source of this ability. Source: Collision Detection, 9/06 [READ ARTICLE] NY Times, 8/29/06 [READ ARTICLE]

Navy Launches Mid-frequency Sonar EIS for Training off East Coast, Gulf of Mexico, and Hawaii - The US Navy has made it clear that it does not want the stringent measures it agreed to after a court challenge to summer training missions off Hawaii to set a precedent for future permits. In order to establish a clear set of standards (and partially in response to a broader court challenge demanding a NEPA process for mid-frequency sonar), the Navy has announced its intention to develop and EIS to choose locations off the east coast and in the Gulf of Mexico for mid-frequency sonar training missions, and a similar EIS for training off Hawaii. Public scoping comments are being accepted on the East Coast EIS until December 1, and the Hawaii EIS until October 13. [SEE EAST COAST/GOM EIS NOTICE OF INTENT] [SEE EAST COAST/GOM EIS WEBPAGE] [SEE HAWAII EIS NOTICE OF INTENT] [HAWAII NAVY EIS WEBPAGE] News Sources: Honolulu Star-Bulletin, 8/27/06 [READ ARTICLE] Honolulu Star-Bulletin, 8/30/06 [READ ARTICLE] Navy Times, 8/31/06 [READ ARTICLE]
Related: Navy Applies for LFAS Permits - The Navy has submitted a request to NMFS for small-takes permits allowing operation of four low-frequency active sonar vessels in several oceans. The permit request is consistent with the ongoing Supplemental Environmental Impact Statement being developed by the Navy. Public comments are being accepted through October 30. [SEE FEDERAL REGISTER NOTICE]
[See AEI Special Report: Active Sonars]

Stringent Standards for Seismic Exploration Challenged by Conoco - This summer, the NMFS issued permit standards for oil exploration off Alaska's North Slope that called for protecting migrating groups of cow-calf pairs of bowhead whales from sound that may cause them to change course. This is the first time in recent years that regulators set the standard low enough to address behavioral disruption, rather than simply attempting to protect whales from sounds loud enough to cause temporary hearing loss. The permit issued for surveys in the Chukchi Sea called for monitoring out to distances where airgun sounds had dissipated to 120dB; previous permits had set monitoring and "safety" zones only in areas where sound is 180dB or above (occasionally dropping to 160dB). Conoco has been proceeding with the new standards, but after seven weeks of operations, filed suit against NMFS, claiming that the 120dB standard is "arbitrary," and therefore a violation of the Marine Mammal Protection Act; the federal district court agreed to a temporary reprieve from the more stringent measures. From mid-September to mid-October, bowheads are expected to be migrating through the survey area, and so may have triggered shut-down provisions. Conoco had been using unmanned aerial drones, as well as manned boats, to monitor the much-larger area around its seismic vessel. The NMFS is fighting the suit, joined by the Alaskan native community at Point Hope. NMFS maintains that the 120dB standard is appropriate; despite good recovery by bowheads, long-term population health requires minimizing stress on the especially sensitive cow-calf pairs. Sources: Alaska Journal of Commerce, 9/24/06 (rules lifted) [READ ARTICLE] AP/Anchorage Daily News, 9/16/06 [READ ARTICLE] Anchorage Daily News (staff article), 9/16/06 [READ ARTICLE] Alaska Journal of Commerce, 9/16/06 [READ ARTICLE] Alaska Journal of Commerce, 8/18/06 [READ ARTICLE]

Cows Have Regional Accents - After farmers began commenting among themselves about the slightly different tones of their cows' moos, researchers decided to take a closer listen. John Wells, Professor of Phonetics at the University of London, said regional twangs had been seen before in birds. The farmers in Somerset who noticed the phenomenon said it may have been the result of the close bond between them and their animals. Farmer Lloyd Green, from Glastonbury, said: "I spend a lot of time with my ones and they definitely moo with a Somerset drawl. I've spoken to the other farmers in the West Country group and they have noticed a similar development in their own herds. It works the same as with dogs - the closer a farmer's bond is with his animals, the easier it is for them to pick up his accent." Source: BBC, 8/23/06 [READ ARTICLE]

Ocean Getting Noisier, Shipping is Main Source - A new study of long-term noise levels in southern California offshore waters indicates that background noise levels have increased about tenfold since the 1960s. The results, which showed a 10-12db increase, are consistent with a similar study done further north several years ago. "If we've doubled the number of ships and we've documented 10 times more noise, then the noise increase is due to both more ships and noisier individual ships than in the '60s. And that may be because the ships are now bigger, faster and have more propulsion power," Scripps researcher John Hildebrand said. Source: ENS, 8/21/06 [READ ARTICLE]

Volcanic Activity Turned into Sound, May Improve Eruption Predictions - Geologists have developed a new sonification technique that translates seismic activity data into sound. Listening to the sound files, as well as creating "scores" that can be analyzed, may allow scientists to detect subtle changes that precede increased activity. Source: ScienceDaily, 8/10/06 [READ ARTICLE] LISTEN TO SOUNDS: [MOUNT ETNA(aif)] [TUNGURAHUAS(aif)] SEE SCORE: [TUNGURAHUASA(pdf)]

Ultrasound Affects Embryonic Brain Development in Mice - Prolonged exposure to ultrasound caused small but significant changes in neural development in mice during late stages of embryonic development. The degree of the effect, in which neurons remained scattered rather than migrating to their proper locations, varied widely but increased as the duration of ultrasound exposure went up. Effects were seen with 30 minutes of exposure; researchers stressed that the use of ultrasound for medical diagnostics is not questioned by these results, but that the study should warn against non-medical use of ultrasound. Source: ScienceDaily, 8/9/06 [READ ARTICLE]

Harp Music Eases Post-Surgical Stress, Stabilizes Heartbeat of Anesthesized Patients - The science blog Collision Detection recently compiled several fascinating articles on research into the use of music to calm medical patients. A study in a cardiac recovery unit at the Chester NJ hospital is confirming long-held suspicions that music can help calm patients. "When I was coming out of it, I was filled with tubes - a throat tube, an oxygen tube - and it was very hard to breathe," one patient said. "You feel you're going to gag. The music calmed my body and allowed me to stop thinking about what was going on. It allowed me to feel more relaxed and rested." A related study by cardiac researcher Abraham Kocheril found that harp music appeared to regularize heartbeats of patients under anesthesia, making an unhealthy heart function more like a healthy one and, presumably, improving the patients' chances on the operating table. Another researcher, Harvard's Ary Goldberg, suggests that there are fractal features common to both music and the human heartbeat, and that music can help tune the heart with healthy fractal noise, allowing it to respond with more dynamism to a bigger array of physical challenges. Source: Collision Detection, 8/06 [READ POST]

Acoustician/Artist Turns Whale Songs into Mandala Images - Mark Fisher, California artist, trained as an acoustics engineer, is using "wavelets," a mathematical technique that can capture intricate detail without losing the larger context, to generate circular images of the patterns revealed inside whale songs. Among whales, certain sounds and patterns are unique to different species, and even individuals in a group - something like an auditory fingerprint, Mr. Fischer said. ''To anyone who doesn't listen to it on a regular basis it sounds like a bunch of clicks,'' he said. ''But if you're a whale -- or someone who studies whales -- it becomes clear that they have their own dialects.'' Wavelets are capable of picking up those distinctions, Mr. Fischer said, nuances that may be missed by the human ear or less detailed visualization methods. ''You can pick out any one of those movies and I'll tell you what it is without hearing a thing,'' he said. ''The differences are that dramatic.'' He envisions a day when researchers may be able to use images generated using wavelets to identify and track individual whales. Sources: NY Times, 8/1/06 [READ ARTICLE] AquaSonics Website (Fisher site) [WEBSITE]