Tag Archives: david orenstein

More Seniors Being Held for Observation

By Guest PostJune 10, 2012General, Healthaffordable care act, brad wright, brown university, david orenstein, elderly patients, emergency departments, gerontologists, health affairs, hospitals, medicare, vincent mor, zhanlian feng

A new study finds that more elderly patients in the emergency departments of hospitals are being held for observation rather than admitted as inpatients. Pressure from Medicare to reduce unnecessary hospitalization may be driving the trend. But being classified as an outpatient, rather than being admitted, can increase out-of-pocket costs for patients. The study is reported in the June edition of Health Affairs.

PROVIDENCE, R.I. [Brown University] — Nobody wins when patients stay in the hospital unnecessarily, so the federal government in recent years has pushed hospitals to be careful about admitting Medicare recipients as inpatients. The apparent result is that more patients are being “held for observation” instead, according to a new study by Brown University gerontologists. While the shift in how hospitals care for elderly patients in the emergency department may reduce costs to Medicare, it can also increase out-of-pocket expenditures for patients. (more…)

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…)

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…)

Constantine Gatsonis: Better Triage for Chest Pains

By Guest PostMarch 27, 2012Scienceacrin, acute coronary syndrome, biostatistician, brad snyder, brown, cancer, cardiac disease, ccta, constantine gatsonis, ct angiography, david orenstein, erin greco, heart attack, philadelphia, radiology

In a study in The New England Journal of Medicine, authors including biostatisticians from Brown report that coronary computed tomographic angiography (CCTA) is a safe way to screen patients coming to the ER with chest pains who are not at high risk for acute coronary syndrome. Patients who got CCTA and tested negative were more likely to be discharged home and spend less time at the hospital.

Coronary computed tomographic angiography (CCTA), a technology for diagnostic imaging of the heart, is a safe way to assess whether patients whose risk of heart attack is not high need to be hospitalized when they arrive at the emergency room complaining of chest pains. Brown biostatisticians led by Constantine Gatsonis are part of a team of researchers who report that finding in The New England Journal of Medicine and at the American College of Cardiology Conference March 26. (more…)

Exposed To Phthalates as Fetuses, Female Mice Have Altered Reproductive Lives

By Guest PostMarch 20, 2012Sciencebenjamin moyer, brown university, cell growth, chemical, concern list, corn oil, david orenstein, dehp, doses of phthalates, exposure scenario, female mouse fetuses, health effect, in utero, industrial chemical, mammary glands, mary hixon, mehp, mice, organism, Phthalates, plastics, precancerous lesions, reproductive lifespan, reproductive system, toxicology

Many environmental and public health officials are concerned about the potential health effects of phthalates, which are common chemicals used to make plastics softer and more pliable. In the first study to examine what effect in utero doses of phthalates have on the reproductive system of mice, Brown University toxicologists found that extremely high doses were associated with significant changes, such as a shortened reproductive lifespan and abnormal cell growth in mammary glands.

PROVIDENCE, R.I. [Brown University] — Female mouse fetuses exposed to very high doses of a common industrial chemical that makes plastics more pliable develop significant reproductive alterations and precancerous lesions as they grow up, according to a new toxicology study conducted at Brown University.

The administered doses of MEHP, the chemical that results when animals metabolize the industrial phthalate DEHP, were much higher than any normal environmental exposure that people or animals would encounter, said Mary Hixon, assistant professor of pathology and laboratory medicine (research) in The Warren Alpert Medical School of Brown University and a study co-author. (more…)

Will a Genetic Mutation Cause Trouble? Ask Spliceman

By Guest PostMarch 5, 2012Scienceaaa, ata, brown university, chimpanzees, david orenstein, dna sequences, gene, genetic mutation, human genome mutation database, humans, kian huat lim, messenger rna, Rhesus monkeys, shamil sunyaev, spliceman, web based program, william fairbrother

New, free Web-based software described in the journal Bioinformatics analyzes DNA sequences to determine if mutations are likely to cause errors in splicing of messenger RNA. When gene splicing goes awry, a wide variety of diseases can result.

PROVIDENCE, R.I. [Brown University] — In a brief paper in the journal Bioinformatics, Brown University researchers describe a new, freely available Web-based program called Spliceman for predicting whether genetic mutations are likely to disrupt the splicing of messenger RNA, potentially leading to disease.

“Spliceman takes a set of DNA sequences with point mutations and computes how likely these single nucleotide variants alter splicing phenotypes,” write co-authors Kian Huat Lim, a graduate student, and William Fairbrother, assistant professor of biology, in an “application note” published in advance online Feb. 10. It will appear in print in April. (more…)