Tag Archives: university research

Compressor-free Refrigerator

Compressor-free refrigerator may loom in the future

Refrigerators and other cooling devices may one day lose their compressors and coils of piping and become solid state, according to Penn State researchers who are investigating electrically induced heat effects of some ferroelectric polymers.

“This is the first step in the development of an electric field refrigeration unit,” says Qiming Zhang, distinguished professor of electrical engineering. “For the future, we can envision a flat panel refrigerator. No more coils, no more compressors, just solid polymer with appropriate heat exchangers.”
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Zhang’s approach uses the change form disorganized to organized that occurs in some polarpolymers when placed in an electric field. The natural state of these materials is disorganized with the various molecules randomly positioned. When electricity is applied, the molecules become highly ordered and the material gives off heat and becomes colder. When the electricity is turned off, the material reverts to its disordered state and absorbs heat.

World’s Smallest Snake Found in Barbados

photo of Leptotyphlops carlae

The world’s smallest species of snake, Leptotyphlops carlae, with adults averaging just under 4 inches in length, has been identified on the Caribbean island of Barbados. The species — which is as thin as a spaghetti noodle and small enough to rest comfortably on a U.S. quarter — was discovered by Blair Hedges, an evolutionary biologist at Penn State.

Hedges determined that the Barbados species is new to science on the basis of its genetic differences from other snake species and its unique color pattern and scales. He also determined that some old museum specimens that had been misidentified by other scientists actually belong to this new species.

Scientists use adults to compare sizes among animals because the sizes of adults do not vary as much as the sizes of juveniles and because juveniles can be harder to find. In addition, scientists seek to measure both males and females of a species to determine its average size. Using these methods, Hedges determined that this species, is the smallest of the more than 3,100 known snake species.

According to Hedges, the smallest and largest species of animals tend to be found on islands, where species can evolve over time to fill ecological niches in habitats that are unoccupied by other organisms. Those vacant niches exist because some types of organisms, by chance, never make it to the islands. For example, if a species of centipede is missing from an island, a snake might evolve into a very small species to “fill” the missing centipede’s ecological niche.

In contrast to larger species — some of which can lay up to 100 eggs in a single clutch — the smallest snakes, and the smallest of other types of animals, usually lay only one egg or give birth to one offspring. Furthermore, the smallest animals have young that are proportionately enormous relative to the adults. For example, the hatchlings of the smallest snakes are one-half the length of an adult, whereas the hatchlings of the largest snakes are only one-tenth the length of an adult. The Barbados snake is no exception to this pattern. It produces a single slender egg that occupies a significant portion of the mother’s body.

Learning How Viruses Evade the Immune System

photo of Naama Elefant

MicroRNA genes are a class of very tiny genes found in a variety of organisms. First discovered in 1993 and at the time considered relatively unimportant, they are now recognized as major players in diverse biological processes.

MicroRNAs are important regulators of protein production. Proteins, the building blocks of the cell, must be produced precisely at the right time and place. MicroRNAs specifically latch on to other genes (their targets) and inhibit the production of the protein products of these genes. Hundreds of microRNAs have already been discovered, but the identity of their target genes remains mostly unknown and presents a great challenge in the field.

Elefant developed a computer algorithm that predicts the targets of microRNAs. Her algorithm, named RepTar, searches the thousands of genes in the human genome and through sequence, structural and physical considerations detects matches to hundreds of microRNAs.

For her work in this field, Naama Elefant, a student of Prof. Hanah Margalit of the Faculty of Medicine at the Hebrew University and an Azrieli fellow, was named one of this year’s winners of the Barenholz Prizes for Creativity and Originality in Applied Computer Science and Computational Biology. This discovery also was declared by the magazine Nature Medicine as ”one of the ten notable advances of the year 2007.”
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Awesome Robot: uBot-5

Cool video on the uBot-5 from UMass Amherst.

The uBot-5 is dynamically stable, using two wheels in a differential drive configuration for mobility. Dynamically stable robots are well suited to environments designed for humans where both a high center of mass and a small footprint are often required.

via: Pop Culture and Engineering Intersect

Toyota has long been interested in personal robot assistants. And the uBot-5, under development at UMass-Amherst, is also looking to meeting that need: Robot developed by computer scientists to assist with elder care:

Baby boomers are set to retire, and robots are ready to help, providing elder care and improving the quality of life for those in need.
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The uBOT-5 carries a Web cam, a microphone, and a touch-sensitive LCD display that acts as an interface for communication with the outside world. “Grandma can take the robot’s hand, lead it out into the garden and have a virtual visit with a grandchild who is living on the opposite coast,” says Grupen, who notes that isolation can lead to depression in the elderly.

Grupen studied developmental neurology in his quest to create a robot that could do a variety of tasks in different environments. The uBot-5’s arm motors are analogous to the muscles and joints in our own arms, and it can push itself up to a vertical position if it falls over. It has a “spinal cord” and the equivalent of an inner ear to keep it balanced on its Segway-like wheels.

Such robots have a huge market waiting for them if engineers can provide models that can be useful at the right price. The future of such efforts looks very promising.

Microbes Beneath the Sea Floor

This stuff is cool. Here is the full press release from Penn State, Microbes beneath sea floor genetically distinct

Tiny microbes beneath the sea floor, distinct from life on the Earth’s surface, may account for one-tenth of the Earth’s living biomass, according to an interdisciplinary team of researchers, but many of these minute creatures are living on a geologic timescale.

“Our first study, back in 2006, made some estimates that the cells could double every 100 to 2,000 years,” says Jennifer F. Biddle, PhD. recipient in biochemistry and former postdoctoral fellow in geosciences, Penn State. Biddle is now a postdoctoral associate at the University of North Carolina, Chapel Hill.

The researchers looked at sediment samples from a variety of depths taken off the coast of Peru at Ocean Drilling Site 1229. They report their findings in today’s (July 22) online issue of the Proceedings of the National Academy of Sciences.

“The Peruvian Margin is one of the most active surface waters in the world and lots of organic matter is continuously being deposited there,” says Christopher H. House, associate professor of geoscience. “We are interested in how the microbial world differs in the subsea floor from that in the surface waters.”

The researchers used a metagenomic approach to determine the types of microbes residing in the sediment 3 feet, 53 feet, 105 feet and 164 feet beneath the ocean floor. The use of the metagenomics, where bulk samples of sediment are sequences without separation, allows recognition of unknown organism and determination of the composition of the ecosystem.

“The results show that this subsurface environment is the most unique environment yet studied metagenomic approach known today,” says House. “The world does look very different below the sediment surface.” He notes that a small number of buried genetic fragments exist from the water above, but that a large portion of the microbes found are distinct and adapted to their dark and quiet world.

The researchers, who included Biddle; House; Stephan C. Schuster, associate professor; and Jean E. Brenchley, professor, biochemistry and molecular biology, Penn State; and Sorel Fitz-Gibbon, assistant research molecular biologist at the Center for Astrobiology, UCLA, found that a large percentage of the microbes were Archaea, single-celled organisms that look like Bacteria but are different on the metabolic and genetic levels. The percentage of Archaea increases with depth so that at 164 feet below the sea floor, perhaps 90 percent of the microbes are Archaea. The total number of organisms decreases with depth, but there are lots of cells, perhaps as many as 1,600 million cells in each cubic inch.
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Pseudogap and Superconductivity

MIT physicists shed light on key superconductivity riddle

Hudson’s team is focusing on the state of matter that exists at temperatures just above the temperature at which materials start to superconduct. This state, known as the pseudogap, is poorly understood, but physicists have long believed that characterizing the pseudogap is important to understanding superconductivity.

In their latest work, published online on July 6 in Nature Physics, they suggest that the pseudogap is not a precursor to superconductivity, as has been theorized, but a competing state. If that is true, it could completely change the way physicists look at superconductivity, said Hudson.

“Now, if you want to explain high-temperature superconductivity and you believe the pseudogap is a precursor, you need to explain both. If it turns out that it is a competing state, you can instead focus more on superconductivity,” he said.

Finding the Host Genes Viruses Require

Flu-infected fly cells reveal dependencies of the virus

The new study is important because it demonstrates a rapid-fire technique for identifying host factors such as proteins and carbohydrates that a virus commandeers to successfully infect a cell. By exposing the virus’s dependencies, the Wisconsin team has uncovered a target-rich environment for influenza drug developers.
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By working in fly cells, the Wisconsin team was able to deploy a technique to rapidly and selectively silence thousands of genes to see which were used by the flu virus. Screening a library of some 13,000 genes, the group identified more than 100 whose suppression in fly cells hindered the virus’s ability to successfully take over the cell and make new viruses.

A Whale of a Turbine

A whale of a turbine

a flipperlike prototype is generating energy on Canada’s Prince Edward Island, with twin, bumpy-edged blades knifing through the air. And this summer, an industrial fan company plans to roll out its own whale-inspired model – moving the same amount of air with half the usual number of blades and thus a smaller, energy-saving motor.

Some scientists were sceptical at first, but the concept now has gotten support from independent researchers, most recently some Harvard engineers who wrote up their findings in the respected journal Physical Review Letters.
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when models of the bumpy flippers were tested in a wind tunnel, Fish and his colleagues found something interesting. The flippers could be tilted at a higher angle before stall occurred.

The scientific literature had scant reference to the flipper bumps, called tubercles. Fish reasoned that because the whale’s flippers remained effective at a high angle, the mammal was therefore able to manoeuvre in tight circles. In fact, this is how it traps its prey, surrounding smaller fish in a “net” of bubbles that they are unwilling to cross.

In 2004, along with engineers from the US Naval Academy and Duke University, Fish published hard data: Whereas a smooth-edged flipper stalled at less than 12 degrees, the bumpy, “scalloped” version did not stall until it was tilted more than 16 degrees – an increase of nearly 40 percent.

Fish then partnered with Canadian entrepreneur Stephen Dewar to start WhalePower, a Toronto-based company that licenses the technology to manufacturers.
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It has all been a bit of a culture shock for Fish, who is more at home in the open world of academia than the more secretive realm of inventions and patents. Two decades ago, his only motivation was to figure out what the bumps were for.

“I sort of found something that’s in plain sight,” he says. “You can look at something again and again, and then you’re seeing it differently.”

The Brain Hides Information From Us To Prevent Mistakes

“The main finding of the study is that it has enabled us to confirm that tactile sensations are initially located unconsciously in anatomical coordinates, but they reach our awareness only when the brain has formed an image of their origin in the spatial coordinates, external to the body,” explained Salvador Soto-Faraco. The coexistence of different spatial reference frames in the brain has been known for some time. So has the fact that confusions between them may result in some cases, such as when we invert the usual anatomical position of some body parts (e.g. when crossing our arms over the body midline). “The brain sorts out problems of this kind rapidly, in a matter of tenths of a second. To do so, however, it has to integrate information arriving in formats that are quite disparate”, Sotoa-Faraco added. “Our research has helped us understand how this process works and how the brain manages spatial realignment when faced with conflict”, he concluded.

Interesting. I think my brain might be hiding more from me lately (like right now where the key to my shed is) 🙂

Nearly Waterless Washing Machine

Professor Stephen Burkinshaw, Chair of Textile Chemistry at the University of Leeds, has created a nearly waterless washing machine. Xeros ltd. has been created to commercialize products based on this system (both for home use and for solvent-based commercial garment cleaning). Given the predicted trouble for supplies of freshwater technology that can reduce water use will be very useful.

Virtually waterless washing machine heralds cleaning revolution

Researchers at the University of Leeds have developed a new way of cleaning clothes using less than 2% of the water and energy of a conventional washing machine.
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A range of tests, carried out according to worldwide industry protocols to prove the technology performs to the high standards expected in the cleaning industry, show the process can remove virtually all types of everyday stains as effectively as existing processes whilst leaving clothes as fresh as normal washing. In addition, the clothes emerge from the process almost dry, reducing the need for tumble-dryers.