Tag Archives: brown university

Experiments Inform Study of Crowd Motion

By Guest PostJuly 29, 2012Scienceannual pilgrimage, brown university, crowd behavior, crowd cohesion, crowd motion, electromagnetism, experiment, laws, mathematics, mecca, sayles hall, sayles swarm, school of fish, the haj, william warren

To determine how crowd behavior emerges from individual actions, William Warren, professor of cognitive, linguistic, and psychological sciences, assembled his own crowds and engaged them in an unusual four-day experiment in Sayles Hall. The subjects were equipped with motion capture markers affixed like antennae to bike helmets.

PROVIDENCE, R.I. [Brown University] — What must the staid-faced University luminaries in those portraits around Sayles Hall have thought while they watched this scene play out for four days last week? Over and over, two to 20 young men and women in bike helmets adorned with what appeared to be five large antennae walked back and forth across a cardboard-covered floor. En route to goals marked by numbers just beneath the portraits, they dodged each other and arrangements of cardboard pillars. Each time they generated patterns of foot traffic. (more…)

El Zotz Masks Yield Insights into Maya beliefs

By Guest PostJuly 19, 2012Culture, Science3d image, ancient america, archaeological site, boris beltran, brown university, cast, cultural heritage, diablo pyramid, dupee family, edwin roman, el zotz, guatemala, hieroglyphic text, kinich ajaw, maya belief, maya civilization, Mexico City, night sun, pre colombian mesoamerica, sarah newman, stephen houston, stuccos, sun god, temple, tikal

A team of archaeologists led by Stephen Houston has made a new discovery at the Maya archaeological site in El Zotz, Guatemala, uncovering a pyramid believed to celebrate the Maya sun god. The structure’s outer walls depict the god in an unprecedented set of images done in painted stucco. In 2010, the team uncovered a royal tomb filled with artifacts and human remains at the same site. Researchers believe the pyramid was built to link the deceased lord to the eternal sun.

PROVIDENCE, R.I. [Brown University] — A team of archaeologists led by Brown University’s Stephen Houston has uncovered a pyramid, part of the Maya archaeological site at El Zotz, Guatemala. The ornately decorated structure is topped by a temple covered in a series of masks depicting different phases of the sun, as well as deeply modeled and vibrantly painted stucco throughout.

The team began uncovering the temple, called the Temple of the Night Sun, in 2009. Dating to about 350 to 400 A.D., the temple sits just behind the previously discovered royal tomb, atop the Diablo Pyramid. The structure was likely built after the tomb to venerate the leader buried there. (more…)

Training Improves Recognition of Rapid-Fire Objects

By Guest PostJuly 12, 2012Scienceattentional blink, attentional function, brain activity, brown university, fmri machine, gibberish character, hoon choi, Kazuhisa Shibata, li hung chang, perception, rapid fire objects, sequence, Takeo Watanabe, visual perception

“Attentional blink” is the term psychologists use to describe our inability to recognize a second important object if we see it less than half a second after a first one. It always seemed impossible to overcome, but in a new paper in the Proceedings of the National Academy of Sciences, Brown University psychologists report they’ve found a way.

PROVIDENCE, R.I. [Brown University] — So far it has seemed an irreparable limitation of human perception that we strain to perceive things in the very rapid succession of, say, less than half a second. Psychologists call this deficit “attentional blink.” We’ll notice that first car spinning out in our path, but maybe not register the one immediately beyond it. It turns out, we can learn to do better after all. In a new study researchers now based at Brown University overcame the blink with just a little bit of training that was never been tried before. (more…)

Diagnostic Technique Uses Immune Cell DNA

By Guest PostJuly 10, 2012Scienceafrican american, bladder cancer, blood samples, brock christensen, brown university, carmen marsit, cd4, cell carcinoma, cell membrane, chemical alteration, devin koestler, DNA, granulocyte leukocytes, immune cell, karl kelsey, leukocytes, methylation, ovarian cancer, t lymphocytes

By looking at signature chemical differences in the DNA of various immune cells called leukocytes, scientists have developed a way to determine their relative abundance in blood samples. The relative abundance turns out to correlate with specific cancers and other diseases, making the technique, described in two recent papers, potentially valuable not only for research but also for diagnostics and treatment monitoring.

PROVIDENCE, R.I. [Brown University] — When a person is sick, there is a tell-tale sign in their blood: a different mix of the various types of immune cells called leukocytes. A group of scientists at several institutions including Brown University has discovered a way to determine that mix from the DNA in archival or fresh blood samples, potentially providing a practical new technology not only for medical research but also for clinical diagnosis and treatment monitoring of ailments including some cancers. (more…)

A SMART(er) Way to Track Influenza

By Guest PostJune 12, 2012Scienceaartik sarma, amplification, andrew artenstein, anubhav tripathi, biological debris, brown assay, brown university, carmichael ong, DNA, first aid kit, flu detection test, genetic sequence, H1N1, hiv, influenza rna, influenza rna sequence, iPhone, magnetics, memorial hospital, microfluidics, nasba, nucleic acid sequence, pigs, polymerase chain reaction, prototype, rhode island, rna partners, rna probe, rna strand, smart, smart detector, stephanie mccalla, steven opal, swine flu, tb, tracking of influenza, tuberculosis, united states, virus in mexico

Brown University researchers have created a reliable and fast flu-detection test that can be carried in a first-aid kit. The novel prototype device isolates influenza RNA using a combination of magnetics and microfluidics, then amplifies and detects probes bound to the RNA. The technology could lead to real-time tracking of influenza. Results are published in the Journal of Molecular Diagnostics.

PROVIDENCE, R.I. [Brown University] — In April 2009, the world took notice as reports surfaced of a virus in Mexico that had mutated from pigs and was being passed from human to human. The H1N1 “swine flu,” as the virus was named, circulated worldwide, killing more than 18,000 people, according to the World Health Organization. The Centers for Disease Control and Prevention in the United States said it was the first global pandemic in more than four decades. (more…)

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…)

Physical Properties Predict Stem Cell Outcome

By Guest PostMay 26, 2012Scienceatomic force microscope, bone, bone tissue, brown university, cartilage, eric darling, mesenchymal stem cells, rafael gonzaelz cruz, stiffness, tissue engineer, vera fonseca, viscosity

Tissue engineers can use mesenchymal stem cells derived from fat to make cartilage, bone, or more fat. The best cells to use are ones that are already likely to become the desired tissue. Brown University researchers have discovered that the mechanical properties of the stem cells can foretell what they will become, leading to a potential method of concentrating them for use in healing.

PROVIDENCE, R.I. [Brown University] — To become better healers, tissue engineers need a timely and reliable way to obtain enough raw materials: cells that either already are or can become the tissue they need to build. In a new study, Brown University biomedical engineers show that the stiffness, viscosity, and other mechanical properties of adult stem cells derived from fat, such as liposuction waste, can predict whether they will turn into bone, cartilage, or fat.

That insight could lead to a filter capable of extracting the needed cells from a larger and more diverse tissue sample, said Eric Darling, senior author of the paper published in Proceedings of the National Academy of Sciences. Imagine a surgeon using such a filter to first extract fat from a patient with a bone injury and then to inject a high concentration of bone-making stem cells into the wound site during the same operation. (more…)

Pollination with Precision: How Flowers Do It

By Guest PostMay 23, 2012Naturearabidopsis plants, brown university, chaotic frenzy, female gametes, fertilization, gamete fusion, hap2, kristin beale, logistical efficiency, mark johnson, mechanism, microscope, model, mothers day, mutant sperm, ovule, pollen grains, pollen tubes, pollination, polytubey, precision, reproduction, sex cells, sperm

Pollination could be a chaotic disaster. With hundreds of pollen grains growing long tubes to ovules to deliver their sperm to female gametes, how can a flower ensure that exactly two fertile sperm reach every ovule? In a new study, Brown University biologists report the discovery of how plants optimize the distribution of pollen for successful reproduction.

PROVIDENCE, R.I. [Brown University] — Next Mother’s Day, say it with an evolved model of logistical efficiency — a flower. A new discovery about how nature’s icons of romance manage the distribution of sperm among female gametes with industrial precision helps explain why the delicate beauties have reproduced prolifically enough to dominate the earth.

In pollination, hundreds of sperm-carrying pollen grains stick to the stigma suspended in the middle of a flower and quickly grow a tube down a long shaft called a style toward clusters of ovules, which hold two female sex cells. This could be a chaotic frenzy, but for the plant to succeed, exactly two fertile sperm should reach the two cells in each ovule — no more, no less. No ovule should be left out, either because too many tubes have gone elsewhere, or because the delivered sperm don’t work. (more…)