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Researchers from the University of Maryland have for the first time measured an effect that was predicted more than 40 years ago, called the Casimir torque.

When placed together in a vacuum less than the diameter of a bacterium (one micron) apart, two pieces of metal attract each other. This is called the Casimir effect. The Casimir torque—a related phenomenon that is caused by the same quantum electromagnetic effects that attract the materials—pushes the materials into a spin. Because it is such a tiny effect, the Casimir torque has been difficult to study. The research team, which includes members from UMD’s departments of electrical and computer engineering and physics and Institute for Research in Electronics and Applied Physics, has built an apparatus to measure the decades-old prediction of this phenomenon and published their results in the December 20th issue of the journal Nature.

“This is an interesting situation where industry is using something because it works, but the mechanism is not well-understood,” said Jeremy Munday, the leader of the research. “For LCD displays, for example, we know how to create twisted liquid crystals, but we don’t really know why they twist. Our study proves that the Casimir torque is a crucial component of liquid crystal alignment. It is the first to quantify the contribution of the Casimir effect, but is not the first to prove that it contributes.”

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While studying the chemical reactions that occur in the flow of gases around a vehicle moving at hypersonic speeds, researchers at the University of Illinois used a less-is-more method to gain greater understanding of the role of chemical reactions in modifying unsteady flows that occur in the hypersonic flow around a double-wedge shape.

“We reduced the pressure by a factor of eight, which is something experimentalists couldn’t do,” said Deborah Levin, researcher in the Department of Aerospace Engineering at the University of Illinois at Urbana-Champaign. “In an actual chamber, they tried to reduce the pressure but couldn’t reduce it that much because the apparatuses are designed to operate within a certain region. They couldn’t operate it if the pressure was too low. When we reduced the pressure in the simulation, we found that the instabilities in the calmed down. We still had a lot of the kind of vortical structure—separation bubbles and swirls—they were still there. But the data were more tractable, more understandable in terms of their time variation.”

Levin conducted the research along with her, then, doctoral student Ozgur Tumuklu, and Vassilis Theofilis from the University of Liverpool.

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The flow of granular materials, such as sand and catalytic particles used in chemical reactors, and enables a wide range of natural phenomena, from mudslides to volcanos, as well as a broad array of industrial processes, from pharmaceutical production to carbon capture. While the motion and mixing of granular matter often display striking similarities to liquids, as in moving sand dunes, avalanches, and quicksand, the physics underlying granular flows is not as well-understood as liquid flows.

Now, a recent discovery by Chris Boyce, assistant professor of chemical engineering at Columbia Engineering, explains a new family of gravitational instabilities in granular particles of different densities that are driven by a gas-channeling mechanism not seen in fluids. In collaboration with Energy and Engineering Science Professor Christoph Müller’s group at ETH Zurich, Boyce’s team observed an unexpected Rayleigh-Taylor (R-T)-like instability in which lighter grains rise through heavier grains in the form of “fingers” and “granular bubbles.” R-T instabilities, which are produced by the interactions of two fluids of different densities that do not mix—oil and water, for example—because the lighter fluid pushes aside the heavier one, have not been seen between two dry granular materials.

The study, published today in the Proceedings of the National Academy of Sciences, is the first to demonstrate that “bubbles” of lighter sand form and rise through heavier sand when the two types of sand are subject to vertical vibration and upward gas , similar to the bubbles that form and rise in lava lamps. The team found that, just as air and oil bubbles rise in water because they are lighter than water and do not want to mix with it, bubbles of light sand rise through heavier sand even though two types of sand like to mix.

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(Natural News) Turkish inventors have created a new building material that is five times stronger than titanium and has the density of wood planks. Most remarkably, this new “Metallic wood” is lighter than titanium and still has the chemical stability of metal for use in manufacturing applications.

The new material is made out of nickel-based cellular materials as small as 17 nano-meters in diameter. These electroplated nickel nano-particles are strategically arranged in struts to maximize their load-bearing strength as a whole. This strategic arrangement of nickel makes the material four times stronger than bulk nickel plating. By tinkering with nano-meter-scale geometry, the inventors can increase the strength and density of the new material. This geometric arrangement of cellular materials is spatially organized and repeated to generate the new “Metallic wood” material. This geometric nano-meter engineering feat produces a very dense material, like that of wood. The inventors have even made the material as dense as water (1,000?kg/m3).

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In a proof-of-principle study in mice, scientists at Johns Hopkins Medicine report the creation of a specialized gel that acts like a lymph node to successfully activate and multiply cancer-fighting immune system T-cells. The work puts scientists a step closer, they say, to injecting such artificial lymph nodes into people and sparking T-cells to fight disease.

In the past few years, a wave of discoveries has advanced new techniques to use T-cells – a type of white blood cell – in cancer treatment. To be successful, the cells must be primed, or taught, to spot and react to molecular flags that dot the surfaces of cancer cells. The job of educating T-cells this way typically happens in lymph nodes, small, bean-shaped glands found all over the body that house T-cells. But in patients with cancer and immune system disorders, that learning process is faulty, or doesn’t happen.

To address such defects, current T-cell booster therapy requires physicians to remove T-cells from the blood of a patient with cancer and inject the cells back into the patient after either genetically engineering or activating the cells in a laboratory so they recognize cancer-linked molecular flags.

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The field of robotics is going through a renaissance thanks to advances in machine learning and sensor technology. Each generation of robot is engineered with greater mechanical complexity and smarter operating software than the last. But what if, instead of painstakingly designing and engineering a robot, you could just tear open a packet of primordial soup, toss it in the microwave on high for two minutes, and then grow your own ‘lifelike’ robot?

If you’re a Cornell research team, you’d grow a bunch and make them race.


Lithium batteries are what allow electric vehicles to travel several hundred miles on one charge. Their capacity for energy storage is well known, but so is their tendency to occasionally catch on fire—an occurrence known to battery researchers as “thermal runaway.” These fires occur most frequently when the batteries overheat or cycle rapidly. With more and more electric vehicles on the road each year, battery technology needs to adapt to reduce the likelihood of these dangerous and catastrophic fires.

Researchers from the University of Illinois at Chicago College of Engineering report that graphene—wonder material of the 21st century—may take the oxygen out of lithium battery fires. They report their findings in the journal Advanced Functional Materials.

The reasons catch fire include rapid cycling or charging and discharging, and in the battery. These conditions can cause the cathode inside the battery—which in the case of most lithium batteries is a lithium-containing oxide, usually lithium cobalt oxide—to decompose and release oxygen. If the oxygen combines with other flammable products given off through decomposition of the electrolyte under high enough heat, spontaneous combustion can occur.

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Trade Secretary Ramon Lopez said the DTI would soon launch an initiative to train the country’s IT and engineering graduates to create AI solutions for the global marketplace.


Instead of fearing artificial intelligence (AI), a supposed threat to the country’s thriving business process outsourcing (BPO) industry, the Philippines can position itself as a global AI hub, Trade Secretary Ramon Lopez said.

In a recent chance interview, Lopez said the Department of Trade and Industry would soon launch an initiative to train the country’s IT and engineering graduates to create AI solutions for the global marketplace.

Lopez said the government could team up with successful Filipino technopreneur Dado Banatao to upgrade the skills of the country’s IT, science and engineering graduates.

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