Dinosaur hearing, listening to muscle noise, quieter cubicles

How did the hearing of dinosaurs compare to that of present-day animal species" What are some ways to improve acoustical conditions in office cubicles" How can sound waves diagnose and monitor muscle activity"

These and other questions will be addressed at the 153rd Meeting of the Acoustical Society of America (ASA) which will take place from June 4-8, 2007 in Salt Lake City. Most sessions will be held at the Hilton Salt Lake City Center (255 South West Temple, Salt Lake City, Utah, 801-328-2000). More than 650 papers will be presented.

WORLD WIDE PRESS ROOM

We encourage you to visit ASA's "World Wide Press Room" before and during the meeting. By the week of May 28, the site (http://www.acoustics.org/press) will be updated for the Salt Lake City meeting and will include numerous lay-language versions of selected meeting papers. These papers will enable you to cover the meeting, even if you can't leave your desk.

NOTEWORTHY SALT LAKE CITY MEETING EVENTS

For those at the meeting, there will be noteworthy sessions including an evening tutorial/concert featuring the Salt Lake City Jazz Orchestra, a demonstration of the Mormon Tabernacle Choir's pipe organ, and a presentation on unusual acoustical effects in the Salt Lake Tabernacle. More details can be found later in the release (see "Salt Lake City Sounds" and "Science of Jazz and Yodeling").

MEDIA INQUIRIES AND ONSITE REGISTRATION

Reporters covering the meeting can receive a complimentary press badge to attend all sessions. General information on transportation and hotel accommodations can be found at http://asa.aip.org/saltlakecity/saltlakecity.html . Please return the reply form if you are interested in attending the meeting and/or receiving a copy of the book of abstracts.

PROGRAM HIGHLIGHTS

The following items describe some highlights from among the many papers being given at the meeting. Full abstracts of the presentations mentioned below can be viewed at the ASA Meeting Abstracts Database (http://asa.aip.org/asasearch.html) by typing in the last name of the author or the appropriate paper code. Entire sessions can be accessed by typing in the session code followed by an asterisk (e.g., 2aAB*).

PALEOHEARING--HOW DINOSAURS HEARD THEIR WORLD

Studying the auditory systems of living organisms is helping scientists to learn the evolutionary pressures their ancestors faced, and even to reconstruct the hearing abilities of extinct animals such as dinosaurs and early mammals. According to the University of Maryland's Robert Dooling (dooling@psyc.umd.edu), the inner ears of archosaurs (birds, crocodilians, and extinct dinosaurs) have highly similar structures. The researchers found a relationship between the body mass of a species and the size of a sensory structure in the inner ear known as the basilar papilla. Small, lightweight species with a short basilar membrane can hear higher frequencies than larger species with a longer basilar membrane. Analyzing these and other variables, the researchers suggest that large dinosaurs could mainly hear low frequencies, with a high frequency hearing limit below 3 kHz. For comparison, this is around the upper frequency limit of a conventional telephone; humans speak at frequencies as high as 8 kHz and can hear up to about 20 kHz (2aAB2). Other papers in session 2aAB will explore how the middle ear of mammals evolved as they made the transition from water to land (2aAB3), the identification of over 20 specialized structures that may have enhanced the hearing of various fish species during their evolution (2aAB1), and the notable features of 36 cat species' middle ears, which may provide clues on the evolutionary pressures on them (2aAB4).

LISTENING TO MUSCLE NOISE

Muscles make noise. For example, you can hear the sound of the masseter muscle--a jaw muscle used in chewing food-by propping your head (ear down) in the palm of your hand. The low rumbling comes from the shortening of the actomyosin filaments in the muscle fibers. Muscle noise can be measured using various sensors, such as microphones and even skin-mounted accelerometers. Scientists at the Scripps Institute of Oceanography listen to muscle noise in order to detect muscle stiffness, which in turn can provide information about neuromuscular disease, such as muscular dystrophy. Muscle stiffness was traditionally measured using external radiation sources (such as a vibrating piston). But the Scripps researchers use a process called passive elastography, a low-cost, in-vivo, non-invasive technique in which an array of surface sensors follow the passing of natural shear waves traveling along the muscle fibers. By the way, the Scripps scientists were originally interested in underwater noise effects and only later adapted their work to noise in muscle. (2pUW9; contact Karim Sabra, ksabra@mpl.ucsd.edu)

MEASURING VOCAL STRESSES IN TEACHERS

In classrooms, teachers need to speak frequently, and often loudly, risking occupational damage to their voices. How much do teachers actually speak in the course of a school day" Ingo Titze (ititze@dcpa.org) and Eric Hunter (ehunter@dcpa.org) of the National Center for Voice and Speech (Denver Center for the Performing Arts and also the University of Iowa) will present some detailed new results from a National Center for Voice and Speech data bank (containing nearly 6600 hours of voice data). The project tracked 31 teachers over two weeks and recorded their voices during all waking hours. The data captured voice-production events as short as 0.0316 seconds and as long as 100 s. On average, the teachers had 1,800 occurrences of voicing per hour at work, compared to 1,200 per hour during non-work periods (for a total of as many as 20,000 per day). Voicing occurred 23 percent of the total time at work and diminished to 13 percent during off-work hours and 12 percent on weekends. According to Titze and Hunter, the study helps pave the way for understanding vocal fatigue in terms of repetitive motion (voice on/off) and collision (vibration) of tissue, as well as how the voice can recover from physical stress (5aSC12).

DETECTING BREAST LESIONS WITH VIBRO-ACOUSTOGRAPHY

Vibro-acoustography (VA) is a non-invasive imaging technique using ultrasound to search for lesions in breast tissue. Generally the rival approaches to breast imaging have their weaknesses and strengths. Mammography (using x rays) has trouble detecting lesions in dense breasts often seen in young women. Conventional ultrasound can spot lesions but cannot measure tissue stiffness, a leading indicator of malignancy. By contrast, VA induces a small-scale vibration in the tissue, and it is this low-frequency signal that provides the crucial information about tissue stiffness. Azra Alizad (aza@mayo.edu), who works at the Mayo Clinic, the pioneer in vibro-acoustography research, says that this technique should allow physicians to identify cancer lesions and other abnormalities with higher sensitivity and specificity. Extensive tests of the VA imaging technique have been carried out at the Mayo Clinic. (3aBBa7)

WORKPLACE SPEECH PRIVACY CALCULATOR

Open-plan offices (cubicles) are here to stay. Construction trends continue to bring workers out of private offices and into the open-plan setting. While an open environment fosters accessibility, there is a great need for solutions that counteract the acoustical effects of many employees working closely together. Acoustical scientists and engineers are using existing research to develop software that replicates acoustical conditions in and recommends solutions for these open-plan spaces. Jonathan Kemp of Cambridge Sound Management in Cambridge, MA (jdkemp@cambridgesoundmanagement.com) will present a computerized modeling tool that allows architects and acoustical consultants to maximize speech privacy in open-office spaces while minimizing the cost and complications of implementing their design. In a map of a simulated open-office plan, the tool graphically displays real-time calculations of the "Speech Privacy Index," a quantitative measure of how much speech can be heard in a given environment. The calculator takes into account such variables as partition type, ceiling height, the presence of environmental sounds, and the addition of masking sounds that can obscure speech. It also determines the quantitative conditions likely to cause distractions for an office worker. According to Kemp and colleagues, the Open Office Privacy Calculator has been validated with measured data and through comparison with existing models for predicting speech privacy. (1pAA9)

SALT LAKE CITY SOUNDS

Acoustical consultant Sarah Rollins (sarahr@yantis.com) will discuss interesting acoustical properties in the Salt Lake Tabernacle and Latter-day Saints (LDS) Conference Center. The elongated domed ceiling of the Tabernacle, she says, creates audible sound focusing effects throughout the hall. (4aAA3). The LDS Conference Center contains the largest theater-style auditorium in the world (21,333 seats). In a special session at the Conference Center on Wednesday morning (June 6), John Longhurst, senior organist for the Mormon Tabernacle Choir (longhurstjt@ldschurch.org) will discuss and demonstrate the Conference Center's pipe organ, which contains 7,708 pipes in its 130 ranks. In Longhurst's presentation, attendees will hear the acoustical behavior of a pipe organ in a very large room (3aAA5). Jack M. Bethards of Schoenstein & Co. Organ Builders of San Francisco (jack@schoenstein.com) will discuss the acoustical and architectural considerations for installing organs in large spaces (3aAA4).

SCIENCE OF JAZZ AND YODELING

An evening tutorial and lecture on the first day of the meeting (June 4) will feature the Salt Lake City Jazz Orchestra. Uwe Hansen of Indiana State University (u-hansen@indstate.edu) will describe the basic science of each instrument family: strings, brasses, woodwinds, piano and percussion. Orchestra director Jerry Floor and his players will then perform illustrative demonstrations of each family. The program will conclude with ensemble performances of famous pieces (1eID1). On Tuesday morning, June 5, sixth-grade students will experience hands-on demonstrations of acoustics, including musical instruments and a "ping-pong cannon" that creates shock waves as it shoots balls at high speeds. On Tuesday afternoon, Bill Strong of Brigham Young University (william_strong@byu.edu) will present a mini-concert on yodeling, by expert yodeler Kerry Christensen, who will demonstrate alpine, classical, and humorous yodeling styles (Session 2pMUb).

PREVENTING TERRORIST ACTIVITY IN PORTS AND HARBORS

Acoustics can make ports and harbors more secure. Karim Sabra of the Scripps Institution of Oceanography (ksabra@mpl.ucsd.edu) will present encouraging proof-of-concept measurements of an "acoustic tripwire" surveillance system for detecting intruders in harbor entrances. Their technique is designed for the shallow-water (less than 20 meters deep) choke points of harbor entrances, which often have high levels of ambient noise. Peter J. Stein (pstein@scisol.com) of New Hampshire-based Science Solutions, Inc. will present the Swimmer Detection Sonar Network (SDSN), designed to be a cost-effective method to protect a large area from swimmers intending to carry out terrorist activities. The in-water system consists of sets of sonar dishes that transmit and detect sound waves. Signal-processing algorithms provide automated detection, tracking, and classification of moving objects such as swimmers. The SDSN is already available commercially for wide-scale deployment (2pEA1). Two papers presented by scientists from Stevens Institute of Technology, Hoboken (papers 2aEA4 and 2aEA5) discuss acoustic measurements in New York's Hudson River. Details of acoustic noise produced by ship traffic will be presented by Heui-Seol Roh. The measurements may provide a basis for developing systems that can detect underwater threats. Brian Borowsky will present an estimation of the distances at which threats can be detected (2pEA6; contact Alexander Sutin, asutin@stevens.edu).

RESTORING QUIET IN NATIONAL PARKS

Is quiet an endangered resource in U.S. National Parks" According to Kurt Fristrup (kurt_fristrup@nps.gov) of the US National Park Service (NPS), the extraordinary quiet of many backcountry sites is increasingly compromised by aircraft noise. In order to fulfill their mandate to protect natural, cultural, and historic resources, as well as visitor experience, NPS has developed analytical tools to assess lost opportunities to hear and respond to the sounds of nature. At the Grand Canyon, efforts are being made to implement the National Parks Overflights Act of 1987, which calls for the timely, substantial restoration of natural quiet to the park from aircraft noise. Dickson Hingson of the Sierra Club's National Parks and Monument Committee (dhingson@infowest.com) will discuss the current status of these efforts, as a deadline of April 22, 2008 approaches for implementing the act. Leslie Blomberg of the Noise Pollution Clearinghouse will propose 10 ways to reduce noise in natural parks. For example, Blomberg says, the simple step of using quieter pavement materials could cut road noise in half in the main entrance of the Florida Everglades. Blomberg (npc@nonoise.org) notes that noise in national parks follows the same consistent pattern associated with other modern noise: the invention of new noise sources, the growth in use of those sources, and the spread of those sources into previously quiet areas. (Session 4aNSa)

CATCHING KILLER WHALES IN THE ACT

Catching killer whales hunting their prey has been difficult, in part because they appear to strike at night. Among the most elusive of killer whales are the "transient" type, so-named because they follow unpredictable paths as they travel from location to location along the west coast of North America. Transients, which also distinguish themselves by feeding primarily on other marine mammals such as seals, refrain from vocalizing while hunting so that prey will not be alerted to their presence. When they begin feeding, they become more vocal. Learning more about the foraging behavior of transients is important for understanding their important roles in the marine ecosystem. To increase opportunities for observing the whales, Kelly Newman (k.newman@sfos.uaf.edu) and Alan Springer of the University of Alaska deployed an autonomous recording unit to listen for them continuously off shore of a fur seal rookery in the Bering Sea in Alaska. They detected killer whale vocalizations on 19 of 20 days during last summer. Most of the vocalizations occurred from twilight to mid-morning. The fewest sounds occurred between the early evening and midnight. Following the paradigm that transients are most vocal when feeding, these results suggest that more feeding occurred at night when it is not possible to observe them visually. This acoustic information is a valuable supplement to traditional visual observations, and is shedding new light on the behavior of this still-mysterious class of killer whales. (3aAB4)

THE SOUNDSCAPE OF MODERNITY

Acoustical developments in the 20th century forever altered the sounds that U.S. residents heard and their ways of listening. Modern acoustical inventions such as sound meters, microphones, and reverberation equations brought about a new level of clarity and similarity in the acoustical environments of disparate locations from Boston concert halls to New York skyscrapers and Hollywood sound stages. Princeton's Emily Thompson (emilyt@princeton.edu), a technology historian, will explore the history of modern sound in early 20th-century United States. "While this new modern sound said little about the physical spaces in which it was produced," Thompson writes, "it has much to tell us about the culture that created it." (2pAAb1)

REHABILITATING THE WORLD'S WORST SOUNDS

Something that is very 21st century is the ability to gradually morph, or transform sounds from one to another. A variation of morphing is to transfer the features of one sound, say a cat's meow, to another sound, such as a musical instrument. Kelly Fitz of Starkey Hearing Research Center in Berkeley, Calif. (kelly_fitz@starkey.com) will describe the state of sound morphing, which can now be done with very good sound quality using modern signal processing techniques. As an illustrative demonstration, Fitz will transform some of the "world's worst sounds" (as determined by UK acoustician Trevor Cox, http://www.sound101.org/) into more pleasing (or at least entertaining) ones. Morphing is often applied to film soundtracks (as audio special effects) and music synthesis. (3pID2).

ALIEN SOUNDSCAPES

Crackling electricity in the atmosphere" Howling red dust storms" Sounds that become muffled from just a few feet away" At session 3aPAb, researchers will present the latest theoretical and experimental knowledge on acoustical conditions on several other terrestrial bodies in our solar system. In addition, Martin Towner of The Open University in the United Kingdom (martintowner@googlemail.com) and others will discuss the acoustic instrumentation that has been flown to date in space missions, particularly the Huygens probe that landed on Saturn's moon Titan (3aPAb1). John Zarnecki of The Open University (j.c.zarnecki@open.ac.uk) will explain how the Huygens probe deployed a simple sonar system and speed-of-sound sensor to constrain the methane content on the planet and provide information on surface properties such as terrain topography (3aPAb4). Jean-Pierre Williams (jpierre@gps.caltech.edu), Andi Petculescu (U. of Louisiana at Lafayette, andi@louisiana.edu), and Amanda Hanford of Penn State University (ald227@psu.edu) will present computer simulations and theoretical models that predict acoustic propagation in the atmospheres of various bodies such as Titan, Venus, and Mars (3aPAb3, 3aPAb5, 3aPAb6). Gregory Delory of UC Berkeley (gdelory@ssl.berkeley.edu) will discuss what was intended to be the first audio microphone deployed on another planet--the Mars Microphone for the ill-fated Mars Polar Lander in 1999--and explain how it has stimulated ideas for acoustical exploration of space (3aPAb2). Michael Yang of ATA Engineering in San Diego (michael.yang@ata-e.com) will discuss acoustical issues associated with SpaceX's Falcon 1. The Falcon 1 is designed to minimize the price per launch and increase reliability for low-Earth-orbit satellites (2pSA1).

MYTH-BUSTING IN MUSICAL INSTRUMENTS

Do violin and guitar instruments truly improve their sound quality and playability over time" Examining this "played in" theory, Andrew Piacsek of Central Washington University (piacsek@cwu.edu) will review the state of current knowledge on this question, and will propose specific ideas for helping to resolve this issue (4pMU5). Scientist and instrument-maker Richard Smith (richard@smithwatkins.com) will dispel and correct what he has identified to be some mistaken notions about brass instruments. For example, Smith says, trumpets are not supposed to play high notes around the frequency range of 2 kHz, according to some acoustics textbooks, yet some skilled trumpet players are able to hit those frequencies. In addition, he says, manufacturers and teachers sometimes incorrectly apply the concepts of fluid dynamics to the study of brass instruments, giving improper scientific authority to some teaching statements and product descriptions (4pMU1). In wind instruments, an area of controversy has been whether their sound quality and responsiveness are significantly affected by the thicknesses of an instrument wall and the exact materials of which the wall is made. Many acousticians had assumed that the main important factor was the profile of a wind instrument's bore, the chamber where air vibrates and produces pitch. Wilfried Kausel of the University of Music and Performing Arts in Austria (kausel@mdw.ac.at) will present growing experimental evidence that wall vibrations and thickness are important (4pMU2).

REDUCING NOISE IN MRI SCANNERS

Magnetic resonance imaging (MRI) scanners are becoming an increasingly useful medical tool. However, they produce very loud noise that may pose a hazard to both participants and scanner operators. Acoustical researchers are devising various approaches to making the machines quieter. A UK team (including Deborah Hall, MRC Institute of Hearing Research, Nottingham, d.hall@ihr.mrc.ac.uk) will present an active noise control system that cancels out some of the sound from the machines. The system takes into account known properties of the MRI machine sound and counteracts them. When tested with human listeners, the system reduced noise levels and improved audibility conditions for sounds, without interfering with the MRI's scanner's image quality (4pPP16).

TURNING VOICE LESSONS INTO A SCIENCE

Drawing from knowledge of acoustics and human anatomy, researchers in session 2pMUa will discuss the latest ideas for teaching voice students to improve their singing. California-based master voice instructor Lisa Popeil (lisa@popeil.com) will explain how a singer can hear and produce three important frequency bands of harmonics: ring (2500-3500 Hz), which helps singers to project their voices in an unamplified setting; brightness (5-15 kHz), important for conveying certain emotions such as happiness; and nasality (200-2000 Hz), which is becoming used as a popular commercial style for enhancing emotion. Brian Monson of the University of Arizona (bbmonson@email.arizona.edu) will discuss the idea of teaching voice students to reach vocal resonances by training them to achieve a 1:6 ratio in the areas of two anatomical regions: the pharanx and the epilarynx. When a teacher provides verbal critiques on a student's singing performance, the information may be imprecisely stated, or misinterpreted by the student. Addressing this issue, David M. Howard of the University of York (dh@ohm.york.ac.uk) will present a real-time display system for singing-voice development. The system provides quantitative visual feedback that helps students see their vocal performance and produce better results.

Source : American Institute of Physics