Tag Archives: brown university

Brian Reggiannini Figures out Who’s Talking

By Guest PostMay 19, 2012Sciencealgorithms, analog devices, brian reggiannini, brown university, commercial success, computer, conventional wisdom, david orenstein, harvey silverman, industry, microphone, microphone arrays, modeling talkers, norwood, speaker, speaker recognition, who is talking

If computers could become ‘smart’ enough to recognize who is talking, that could allow them to produce real-time transcripts of meetings, courtroom proceedings, debates, and other important events. In the dissertation that will allow him to receive his Ph.D. at Commencement this year, Brian Reggiannini found a way to advance the state of the art for voice- and speaker-recognition.

Everyone does signal processing every day, even if we don’t call it that. With friends at a sports bar, we peer up at the TV to see the score, we turn our head toward the crashing sound when a waitress drops a glass, and perhaps most remarkably, we can track the fast-paced banter of all the people in our booth, even if we’ve never met some of the friends-of-friends who have insinuated themselves into the scene.

Very few of us, however, could ever get a computer to do anything like that. That’s why doing it well has earned Brian Reggiannini a Ph.D. at Brown and a career in the industry.

In his dissertation, Reggiannini managed to raise the bar for how well a computer connected to a roomful of microphones can keep track of who among a small group of speakers is talking. Further refined and combined with speech recognition, such a system could lead to instantaneous transcriptions of meetings, courtroom proceedings, or debates among, say, several rude political candidates who are prone to interrupt. It could help the deaf follow conversations in real-time. (more…)

Five-Limbed Brittle Stars Move Bilaterally, Like People

By Guest PostMay 14, 2012Natureanimals, belize, bilateral symmetry, bilaterally symmetrical, brain, brittle stars, brown university, bushnell foundation, david orenstein, direction, five limbed, henry astley, humans, locomotion, mark bertness, move bilaterally, ophiocoma echinata, pentaradially symmetrical, radial symmetrical

Brittle stars and people have something in common: They move in fundamentally similar ways. Though not bilaterally symmetrical like humans and many other animals, brittle stars have come up with a mechanism to choose any of its five limbs to direct its movement on the seabed. It’s as if each arm can be the creature’s front, capable of locomotion and charting direction. Results appear in the Journal of Experimental Biology.

PROVIDENCE, R.I. [Brown University] — It appears that the brittle star, the humble, five-limbed dragnet of the seabed, moves very similarly to us.

In a series of first-time experiments, Brown University evolutionary biologist Henry Astley discovered that brittle stars, despite having no brain, move in a very coordinated fashion, choosing a central arm to chart direction and then designating other limbs to propel it along. Yet when the brittle star wants to change direction, it designates a new front, meaning that it chooses a new center arm and two other limbs to move. Brittle stars have come up with a mechanism to choose any of its five limbs to be central control, each capable of determining direction or pitching in to help it move. (more…)

Locked RNA Editing Yields Odd Fly Behavior

By Guest PostApril 26, 2012Scienceabiotic factor, als, arthur sugden, asli sahin, brown university, cell, charles lawrence, dadar, enzyme adar, epilepsy, factor, fruit fly, function, genetic, jacquelyn dorsky, james jepson, lauren alpert, locking down, lou gehrigs disease, nucleus, organism, phenomenon, protein, rna, robert reenan, suicidal depression, temperature, wallflowers, yiannis savva

At the level of proteins, organisms can adapt by editing their RNA — and an editor can even edit itself. Brown University scientists working with fruit flies found that “locking down” the self-editing process at two extremes created some strange behaviors. They also found that the process is significantly affected by temperature.

PROVIDENCE, R.I. [Brown University] — Because a function of RNA is to be translated as the genetic instructions for the protein-making machinery of cells, RNA editing is the body’s way of fine-tuning the proteins it produces, allowing us to adapt. The enzyme ADAR, which does this editing job in the nervous system of creatures ranging from mice to men, even edits itself. In a new study that examined the self-editing process and locked it down at two extremes in fruit flies, Brown University scientists found some surprising insights into how this “fine-tuning of the fine-tuner” happens, including bizarre behavioral effects that come about when the self-editor can’t edit. (more…)

Distinct Brain Cells Recognize Novel Sights

By Guest PostApril 16, 2012Sciencebrain area, brain cell, brown university, cell type, david orenstein, david sheinberg, excitatory neuron, inferior temporal cortex, itc, luke woloszyn, novel sight, plasticity, repair circuit, skull, traumatic brain injury

The brain’s ability to learn to recognize objects plays out in the inferior temporal cortex. A new study offers a possible explanation of how two classes of neurons play distinct roles to help that happen.

PROVIDENCE, R.I. [Brown University] — No matter what novel objects we come to behold, our brains effortlessly take us from an initial “What’s that?” to “Oh, that old thing” after a few casual encounters. In research that helps shed light on the malleability of this recognition process, Brown University neuroscientists have teased apart the potentially different roles that two distinct cell types may play.

In a study published online in advance in the journal Neuron, the researchers document that this kind of learning is based in the inferior temporal cortex (ITC), a brain area buried deep in the skull. Scientists already knew the area was important for visual recognition of familiar items, but they hadn’t figured out the steps required to move from novelty to familiarity, a process they refer to as “plasticity.” (more…)

Bats Save Energy By Drawing in Wings on Upstroke

By Guest PostApril 13, 2012Nature, Scienceaerodynamics, attila bergou, bat wings, bats, brown university, calculation, calculus rich model, daniel riskin, david orenstein, flying machine, inertial energy, muscular wings, physicisist, sharon swartz, wing mass

Bat wings are like hands: meaty, bony and full of joints. A new Brown University study finds that bats take advantage of their flexibility by folding in their wings on the upstroke to save inertial energy. The research suggests that engineers looking at flapping flight should account for wing mass and consider a folding design.

PROVIDENCE, R.I. [Brown University] — Whether people are building a flying machine or nature is evolving one, there is pressure to optimize efficiency. A new analysis by biologists, physicists, and engineers at Brown University reveals the subtle but important degree to which that pressure has literally shaped the flapping wings of bats.

The team’s observations and calculations show that by flexing their wings inward to their bodies on the upstroke, bats use only 65 percent of the inertial energy they would expend if they kept their wings fully outstretched. Unlike insects, bats have heavy, muscular wings with hand-like bendable joints. The study suggests that they use their flexibility to compensate for that mass. (more…)

Transactional Memory: An Idea Ahead of Its Time

By Guest PostApril 10, 2012Science, Technologyamherst, ars technica, blue gene, brown university, buzz, computer, computer scientist, computing technology, core processor, eliot moss, hardware architecture, hardware computing, haswell, ibm, maurice herlihy, mike cohea, parallel processor, q supercomputer, richard lewis, transactional memory, university of massachusetts

Nearly 20 years ago, two Brown University computer scientists were working on a largely theoretical problem: How could multiple parallel processors make changes to shared resources safely and efficiently? Their proposal — transactional memory — is sparking fresh interest as a new generation of processors seeks improved power and speed.

In 1993, Maurice Herlihy and a colleague published a paper on transactional memory — a new, clever tactic in computing to deal with handling shared revisions to information seamlessly and concurrently. Few noticed.

Nearly 20 years later, transactional memory is an idea that’s now the rage in hardware computing, and Herlihy, computer science professor at Brown University, has morphed into a prophet of sorts, a computing pioneer who was far ahead of his time. Intel recently announced that transactional memory will be included in its mainstream “Haswell” hardware architecture by next year. IBM has adopted transactional memory in the Blue Gene/Q supercomputer. The original paper by Herlihy and Eliot Moss has been cited more than 1,300 times. (more…)

Newly Found Protein Helps Cells Build Tissues

By Guest PostApril 2, 2012Scienceantibody, bmps, bone morphogenic proteins, brown university, enzyme, fruit flies, gbb, gbb38, glass bottom boat, guillermo marques, kristi wharton, molecule, protein, signaling molecule, takuya akiyama, wing tissue

University biologists have found a new molecule in fruit flies that is key to the information exchange needed to build wings properly. They have also uncovered evidence that an analogous protein may exist in people and may be associated with problems such as cleft lip, or premature ovarian failure.

PROVIDENCE, R.I. [Brown University] — As they work together to form body parts, cells in developing organisms communicate like workers at a construction site. The discovery of a new signaling molecule in flies by Brown University biologists not only helps explain how cells send many long-haul messages, but also provides new clues for researchers who study how human development goes awry, for instance in cases of cleft lip and palate. (more…)

‘Bed-of-Nails’ Breast Implant Deters Cancer Cells

By Guest PostMarch 26, 2012Healthbed of nails, blood vessel, breast cancer, brown university, cancer tumor, cell, cell function, chemical analysis, electron spectroscopy, lijuan zhang, malignant, michael platek, nanoscale, Nanotechnology, plga, protein, regrowth, thomas webster, tumor, united states, university of rhode island, vegf

Researchers at Brown University have created an implant that appears to deter breast cancer cell regrowth. Made from a common federally approved polymer, the implant is the first to be modified at the nanoscale in a way that causes a reduction in the blood-vessel architecture that breast cancer tumors depend upon, while also attracting healthy breast cells. Results are published in Nanotechnology.

PROVIDENCE, R.I. [Brown University] — One in eight women in the United States will develop breast cancer. Of those, many will undergo surgery to remove the tumor and will require some kind of breast reconstruction afterward, often involving implants. Cancer is an elusive target, though, and malignant cells return for as many as one-fifth of women originally diagnosed, according to the American Cancer Society. (more…)