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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…)

Researchers Make Living Model of Brain Tumor

By Guest PostFebruary 20, 2012Science3 d characteristics, 3 d model, 3d glioma model, agarose hydrogel mold, anti therapeutic agent, aruna sigdel, blood vessel, brain tumor, brown university, chenjie xu, concept, diameter, diffusion, don ho, endothelial cell, glioma, iron oxide nanoparticles, jeffrey morgan, magnetic resonance imaging, microns, microtissues, nanocarrier, nathan kohler, petri dish, raghu kalluri, rat, rg2 cell gliomas, richard lewis, shouheng sun, tissue culture, tissue model, tumstatin

*Researchers have created a living 3-D model of a brain tumor and its surrounding blood vessels. In experiments, the scientists report that iron-oxide nanoparticles carrying the agent tumstatin were taken by blood vessels, meaning they should block blood vessel growth. The living-tissue model could be used to test the effectiveness of nanoparticles in fighting other diseases. Results appear in Theranostics.*

PROVIDENCE, R.I. [Brown University] — Brown University scientists have created the first three-dimensional living tissue model, complete with surrounding blood vessels, to analyze the effectiveness of therapeutics to combat brain tumors. The 3-D model gives medical researchers more and better information than Petri dish tissue cultures.

The researchers created a glioma, or brain tumor, and the network of blood vessels that surrounds it. In a series of experiments, the team showed that iron-oxide nanoparticles ferrying the chemical tumstatin penetrated the blood vessels that sustain the tumor with oxygen and nutrients. The iron-oxide nanoparticles are important, because they are readily taken up by endothelial cells and can be tracked by magnetic resonance imaging. (more…)

J. Timmons Roberts: What did Durban do for climate?

By Guest PostDecember 13, 2011Environment1992 earth summit, american, atmosphere, brown researchers, carbon dioxide, center for environmental studies, China, climate change, climate change negotiations, climate talks in durban, copenhagen, democrats, durban, environmental experts, fossil fuel emissions, global citizens, global network, greenhouse gas emissions, India, j timmons roberts, kyoto protocol, mood, republicans, richard lewis, rio de janeiro, South Africa, timmons roberts, united nations, united states

J. Timmons Roberts, professor of sociology and director of the Center for Environmental Studies, led a group of Brown researchers and students to the United Nations climate change negotiations in Durban, South Africa. On his return, Roberts spoke with Richard Lewis, reflecting on the Durban meetings, the status of research, and the challenges of activism on issues of climate change.

Timmons Roberts, professor and director of the Center for Environmental Studies, has just returned from attending climate talks in Durban, South Africa. Roberts and a delegation from Brown — faculty, postdoctoral researchers, graduate and undergraduate students — witnessed the negotiations up close as observers to ministerial speeches and negotiations. The talks ended with an agreement to extend the greenhouse gas emissions targets set under the Kyoto Protocol and a pledge to work on a replacement treaty incorporating the United States, China, and India.

Roberts spoke with Richard Lewis on the importance of the talks, the need for industrialized countries to compensate developing countries for damages from climate change, and the unique opportunity for people from Brown’s environmental program to attend the talks. (more…)

Frogs’ Amazing Leaps Due to Springy Tendons

By Guest PostDecember 3, 2011Nature, Science3 d x ray video technology, biomechanics of frog jumping, brown university, bush babies, calaveras county, elastic mechanism, elastic structure, frog jumping, frog jumping competition, frogs, grasshopper, guinea fowl, henry astley, humble flea, invertebrates, milliseconds, muscles, northeast united states, northern leopard frog, pond frog, rana pipiens, richard lewis, species of frogs, thomas roberts, vertebrates

*The secret to frogs’ superlative jumping lies in their tendons. Researchers at Brown University, filming frogs jumping at 500 frames per second with special X-ray technology, show that the frog’s tendon stretches as it readies its leap and then recoils, much like a spring, when the frog jumps. The finding could explain how other animals are exceptional leapers. Results appear in Biology Letters.*

PROVIDENCE, R.I. [Brown University] — Some species of frogs and many other animals are able to jump far beyond what appear to be their capabilities. The trained contestants in the frog-jumping competition in Calaveras County, Calif., come to mind, but even ordinary frogs can leap several times farther than their physiology would seem to allow.

“Muscles alone couldn’t produce jumps that good,” said Henry Astley, who studies the biomechanics of frog jumping at Brown University. (more…)

Tag Archives: richard lewis

Transactional Memory: An Idea Ahead of Its Time

Researchers Make Living Model of Brain Tumor

J. Timmons Roberts: What did Durban do for climate?

Frogs’ Amazing Leaps Due to Springy Tendons