Echolocation Builds Prediction Models of Prey Movement

Echolocation Builds Prediction Models of Prey Movement

Bats use echoes of own vocalizations to anticipate location, trajectory of prey

Media Contact:
Larry Frum
AIP Media
301-209-3090
media@aip.org

SEATTLE, November 30, 2021 — Bats are not only using their acoustical abilities to find a meal — they are also using it to predict where their prey would be, increasing their chances of a successful hunt.

During the 181st Meeting of the Acoustical Society of America, which will be held Nov. 29 to Dec. 3, Angeles Salles, from Johns Hopkins University, will discuss how bats rely on acoustic information from the echoes of their own vocalizations to hunt airborne insects. The session, “Bats use predictive strategies to track moving auditory objects,” will take place Tuesday, Nov. 30, at 1:50 p.m. Eastern U.S.

In contrast to predators that primarily use vision, bats create discrete echo snapshots, to build a representation of their environment. They produce sounds for echolocation through contracting the larynx or clicking their tongues before analyzing the returning echoes. This acoustic information facilitates bat navigation and foraging, often in total darkness.

Echo snapshots provide interrupted sensory information about target insect trajectory to build prediction models of prey location. This process enables bats to track and intercept their prey.

“We think this is an innate capability, such as humans can predict where a ball will land when it is tossed at them,” said Salles. “Once a bat has located a target, it uses the acoustic information to calculate the speed of the prey and anticipate where it will be next.”

The calls produced by the bats are usually ultrasonic, so human hearing cannot always recognize such noises. Echolocating bats integrate the acoustic snapshots over time, with larger prey producing stronger echoes, to predict prey movement in uncertain conditions.

“Prey with erratic flight maneuvers and clutter in the environment does lead to an accumulation of errors in their prediction,” said Salles. “If the target does not appear where the bat expects it to, they will start searching again.”

By amalgamating representations of prey echoes, bats can determine prey distance, size, shape, and density, as well as identify what they are tracking. Studies have shown bats learn to steer away from prey they deem unappetizing.

———————– MORE MEETING INFORMATION ———————–
USEFUL LINKS
Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eventpilotadmin.com/web/planner.php?id=ASASPRING22
Press Room: https://acoustics.org/world-wide-press-room/

WORLDWIDE PRESS ROOM
In the coming weeks, ASA’s Worldwide Press Room will be updated with additional tips on dozens of newsworthy stories and with lay language papers, which are 300 to 500 word summaries of presentations written by scientists for a general audience and accompanied by photos, audio and video. You can visit the site during the meeting at https://acoustics.org/world-wide-press-room/.

PRESS REGISTRATION
We will grant free registration to credentialed journalists and professional freelance journalists. If you are a reporter and would like to attend, contact AIP Media Services at media@aip.org. For urgent requests, staff at media@aip.org can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

Filtering Microplastics Trash from Water with Acoustic Waves

Filtering Microplastics Trash from Water with Acoustic Waves

Prototype speaker system efficiently separates out microplastics from polluted water

Media Contact:
Larry Frum
AIP Media
301-209-3090
media@aip.org

SEATTLE, November 29, 2021 — Microplastics are released into the environment by cosmetics, clothing, and industrial processes or from larger plastic products as they break down naturally.

The pollutants eventually find their way into rivers and oceans, posing problems for marine life. Filtering and removing the small particles from water is a difficult task, but acoustic waves may provide a solution.

Dhany Arifianto, of the Institut Teknologi Sepuluh Nopember in Surabaya, Indonesia, will discuss a filtration prototype in his presentation, “Using bulk acoustic waves for filtering microplastic on polluted water,” on Monday, Nov. 29 at 6:10 p.m. Eastern U.S. at the Hyatt Regency Seattle. The presentation is part of the 181st Meeting of the Acoustical Society of America, taking place Nov. 29 to Dec. 3.

Arifianto and his team used two speakers to create acoustic waves. The force produced by the waves separates the microplastics from the water by creating pressure on a tube of inflowing water. As the tube splits into three channels, the microplastic particles are pressed toward the center as the clean water flows toward the two outer channels.

The prototype device cleaned 150 liters per hour of polluted water and was tested with three different microplastics. Each plastic was filtered with a different efficiency, but all were above 56% efficient in pure water and 58% efficient in seawater. Acoustic frequency, speaker-to-pipe distance, and density of the water all affected the amount of force generated and therefore the efficiency.

The acoustic waves may impact marine life if the wave frequency is in the audible range. The group is currently studying this potential issue.

“We believe further development is necessary to improve the cleaning rate, the efficiency, and particularly the safety of marine life,” said Arifianto.

———————– MORE MEETING INFORMATION ———————–
USEFUL LINKS
Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eventpilotadmin.com/web/planner.php?id=ASASPRING22
Press Room: https://acoustics.org/world-wide-press-room/

WORLDWIDE PRESS ROOM
In the coming weeks, ASA’s Worldwide Press Room will be updated with additional tips on dozens of newsworthy stories and with lay language papers, which are 300 to 500 word summaries of presentations written by scientists for a general audience and accompanied by photos, audio and video. You can visit the site during the meeting at https://acoustics.org/world-wide-press-room/.

PRESS REGISTRATION
We will grant free registration to credentialed journalists and professional freelance journalists. If you are a reporter and would like to attend, contact AIP Media Services at media@aip.org. For urgent requests, staff at media@aip.org can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

Blood Bubbles Reveal Oxygen Levels

Blood Bubbles Reveal Oxygen Levels

Acoustic tools detect vibrating microbubbles, act as oxygen sensors

Media Contact:
Larry Frum
AIP Media
301-209-3090
media@aip.org

SEATTLE, November 29, 2021 – Blood carries vital oxygen through our circulation system to muscles and organs. Acoustic tools can create small bubbles in our blood, capable of changing in response to oxygen and signifying oxygen levels.

During the 181st Meeting of the Acoustical Society of America, which will be held Nov. 29 to Dec. 3, Shashank Sirsi, from the University of Texas at Dallas, will discuss how circulating microbubbles can be used to measure oxygen levels. The talk, “Hemoglobin Microbubbles for In Vivo Blood Oxygen Level Dependent Imaging: Boldly Moving Beyond MRI,” will take place Monday, Nov. 29, at 11:25 a.m. Eastern U.S.

Microbubbles are smaller than one hundredth of a millimeter in diameter and can be made by emulsifying lipids or proteins with a gas. The gas filling of microbubbles causes them to oscillate and vibrate when ultrasound is applied, scattering energy and generating an acoustic response that can be detected by a clinical ultrasound scanner. They are routinely used in medical imaging to provide greater contrast in tissue.

Hemoglobin, the protein that gives red blood cells their signature color, will form a stable shell around microbubbles. It then continues to carry out its typical role of binding and releasing oxygen in blood.

Sirsi and his team developed microbubbles to acoustically detect blood oxygen levels, since the microbubble shells are altered by structural hemoglobin changes in response to oxygen. The hemoglobin shell is continually responsive to oxygen after surrounding the bubble and has been optimized to perform in living organisms’ circulation.

“When oxygen binds to hemoglobin, there are structural changes in the protein that change the mechanical properties,” said Sirsi. “The mechanical properties of the shell dictate the acoustic response of a bubble, so our hypothesis was that different acoustic responses would be seen as the shell gets stiffer or more elastic.”

Preliminary results show a strong correlation between oxygen concentration and the acoustic bubble response, highlighting the potential use of microbubbles as oxygen sensors. This capability would have many benefits for medicine and imaging, including evaluating oxygen-deprived regions of tumors and in the brain.

———————– MORE MEETING INFORMATION ———————–
USEFUL LINKS
Main meeting website: https://acousticalsociety.org/asa-meetings/
Technical program: https://eventpilotadmin.com/web/planner.php?id=ASASPRING22
Press Room: https://acoustics.org/world-wide-press-room/

WORLDWIDE PRESS ROOM
In the coming weeks, ASA’s Worldwide Press Room will be updated with additional tips on dozens of newsworthy stories and with lay language papers, which are 300 to 500 word summaries of presentations written by scientists for a general audience and accompanied by photos, audio and video. You can visit the site during the meeting at https://acoustics.org/world-wide-press-room/.

PRESS REGISTRATION
We will grant free registration to credentialed journalists and professional freelance journalists. If you are a reporter and would like to attend, contact AIP Media Services at media@aip.org. For urgent requests, staff at media@aip.org can also help with setting up interviews and obtaining images, sound clips, or background information.

ABOUT THE ACOUSTICAL SOCIETY OF AMERICA
The Acoustical Society of America (ASA) is the premier international scientific society in acoustics devoted to the science and technology of sound. Its 7,000 members worldwide represent a broad spectrum of the study of acoustics. ASA publications include The Journal of the Acoustical Society of America (the world’s leading journal on acoustics), JASA Express Letters, Proceedings of Meetings on Acoustics, Acoustics Today magazine, books, and standards on acoustics. The society also holds two major scientific meetings each year. See https://acousticalsociety.org/.

Can We Perceive Gender from Children’s Voices?

Can We Perceive Gender from Children’s Voices?

Classification rates for individual talkers (ages 5-11), with numbers indicating talker age (males in circles). Voices in shaded quadrants were identified correctly based on both sentences and isolated syllables. CREDIT: Barreda and Assmann

WASHINGTON, November 23, 2021 — The perception of gender in children’s voices is of special interest to researchers, because voices of young boys and girls are very similar before the age of puberty. Adult male and female voices are often quite different acoustically, making gender…click to read more

From the Journal: The Journal of the Acoustical Society of America
Link to article: Perception of gender in children’s voices
DOI: 10.1121/10.0006785

To Better Understand Speech, Focus on Who Is Talking

To Better Understand Speech, Focus on Who Is Talking

Seeing a talker’s face improves your ability to perceive speech, but only if the face and voice come from the same location in space. CREDIT: Justin Fleming

WASHINGTON, October 26, 2021 — Seeing a person’s face as we are talking to them greatly improves our ability to understand their speech. While previous studies indicate that the timing of words-to-mouth movements across the senses is critical to this audio-visual speech benefit, whether it also depends on…click to read more

From the Journal: The Journal of the Acoustical Society of America
Link to article: Spatial alignment between faces and voices improves selective attention to audio-visual speech
DOI: 10.1121/10.0006415

Attention-Based Deep Neural Network Increases Detection Capability in Sonar Systems

Attention-Based Deep Neural Network Increases Detection Capability in Sonar Systems

ABNN’s gradual focus on specific line-spectrum features of a ship. CREDIT: Institute of Acoustics, Chinese Academy of Sciences

WASHINGTON, October 12, 2021 — In underwater acoustics, deep learning is gaining traction in improving sonar systems to detect ships and submarines in distress or in restricted waters. However, noise interference from the complex marine environment becomes a challenge when…Click here to read more.

From the Journal: JASA Express Letters
Link to article: Underwater acoustic target recognition using attention-based deep neural network
DOI: full/10.1121/10.0006299