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Up until now, the ability to make gray goo has been theoretical. However, the scientists at the Columbia University School of Engineering and Applied Science have made a significant breakthrough. The individual components are computationally simple but can exhibit complex behavior.

Current robots are usually self-contained entities made of interdependent subcomponents, each with a specific function. If one part fails, the robot stops working. In robotic swarms, each robot is an independently functioning machine.

In a new study published today in Nature, researchers at Columbia Engineering and MIT Computer Science & Artificial Intelligence Lab (CSAIL), demonstrate for the first time a way to make a robot composed of many loosely coupled components, or “particles.” Unlike swarm or modular robots, each component is simple, and has no individual address or identity. In their system, which the researchers call a “particle robot,” each particle can perform only uniform volumetric oscillations (slightly expanding and contracting), but cannot move independently.

The team, led by Hod Lipson, professor of mechanical engineering at Columbia Engineering, and CSAIL Director Daniela Rus, discovered that when they grouped thousands of these particles together in a “sticky” cluster and made them oscillate in reaction to a light source, the entire particle robot slowly began to move forward, towards the light.

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These findings support the idea that cognitive decline is in part due to the aging of blood cells, which are produced in the bone marrow.

Abstract
Restoration of cognitive function in old mice by transfer of blood or plasma from young mice has been attributed to reduced C–C motif chemokine ligand 11 (CCL11) and β2-microglobulin, which are thought to suppress neurogenesis in the aging brain. However, the specific role of the hematopoietic system in this rejuvenation has not been defined and the importance of neurogenesis in old mice is unclear. Here we report that transplantation of young bone marrow to rejuvenate the hematopoietic system preserved cognitive function in old recipient mice, despite irradiation-induced suppression of neurogenesis, and without reducing β2-microglobulin. Instead, young bone marrow transplantation preserved synaptic connections and reduced microglial activation in the hippocampus. Circulating CCL11 levels were lower in young bone marrow recipients, and CCL11 administration in young mice had the opposite effect, reducing synapses and increasing microglial activation.


It’s cliché to describe something very noisy as “louder than a jet engine.” But supersonic jet engines, like those powering fighters flown by the U.S. military, are so much louder than regular jet engines that scientists have a special term for their sound—” broadband shock-associated noise.”

Now, a team of faculty and students from the Department of Aerospace Engineering at the University of Kansas will design and test to cut noise from supersonic military jets. The U.S. Department of Defense’s Strategic Environmental Research and Development Program (SERDP), the DoD’s environmental science and technology program, is supporting a one-year, $200,000 effort at KU, with the potential to expand that support in the years ahead.

“This project will test ideas to reduce from supersonic military aircraft,” said Z.J. Wang, Spahr Professor of Aerospace Engineering at KU, who is heading the new effort. “At the moment, the noise is so loud that it affects the health of personnel working in close proximity to the aircraft and people living close to the military base. This is a challenging problem, and we’ve suggested some novel ideas which have potential.”

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Can tokamak fusion facilities, the most widely used devices for harvesting on Earth the fusion reactions that power the sun and stars, be developed more quickly to produce safe, clean, and virtually limitless energy for generating electricity? Physicist Jon Menard of the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) has examined that question in a detailed look at the concept of a compact tokamak equipped with high temperature superconducting (HTS) magnets. Such magnets can produce higher magnetic fields—necessary to produce and sustain fusion reactions—than would otherwise be possible in a compact facility.

Menard first presented the paper, now published in Philosophical Transactions of the Royal Society A, to a Royal Society workshop in London that explored accelerating the development of tokamak-produced with compact tokamaks. “This is the first paper that quantitatively documents how the new superconductors can interplay with the high pressure that compact tokamaks produce to influence how tokamaks are optimized in the future,” Menard said. “What we tried to develop were some simple models that capture important aspects of an integrated design.”

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In mobiles, fridges, planes – transistors are everywhere. But they often operate only within a restricted current range. LMU physicists have now developed an organic transistor that functions perfectly under both low and high currents.

Transistors are that control voltage and currents in electrical circuits. To reduce economic and , must become smaller and more effective. This applies above all to transistors. In the field of inorganic semiconductors, dimensions below 100 nanometers are already standard. In this respect, organic semiconductors have not been able to keep up. In addition, their performance with regard to charge-carrier transport is considerably worse. But organic structures offer other advantages. They can easily be printed on an , the material costs are lower, and they can be transparently applied to flexible surfaces.

Thomas Weitz, a professor in LMU’s Faculty of Physics and a member of the Nanosystems Initiative Munich, and his team are working intensively on the optimization of organic transistors. In their latest publication in Nature Nanotechnology, they describe the fabrication of transistors with an unusual structure, which are tiny, powerful and above all versatile. By carefully tailoring a small set of parameters during the , they have been able to design nanoscale devices for high or low current densities. The primary innovation lies in the use of an atypical geometry, which also facilitates assembly of the nanoscopic transistors.

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The Kaikoura earthquake in New Zealand in 2016 caused widespread damage. LMU researchers have now dissected its mechanisms revealing surprising insights on earthquake physics with the aid of simulations carried out on the supercomputer SuperMUC.

The 2016 Kaikoura earthquake (magnitude 7.8) on the South Island of New Zealand is among the most intriguing and best-documented seismic events anywhere in the world – and one of the most complex. The earthquake exhibited a number of unusual features, and the underlying geophysical processes have since been the subject of controversy. LMU geophysicists Thomas Ulrich and Dr. Alice-Agnes Gabriel, in cooperation with researchers based at the Université Côte d’Azur in Valbonne and at Hong Kong Polytechnic University, have now simulated the course of the earthquake with an unprecedented degree of realism. Their model, which was run on the Bavarian Academy of Science’s supercomputer SuperMUC at the Leibniz Computing Center (LRZ) in Munich, elucidates dynamic reasons for such uncommon multi-segment earthquake. This is an important step towards improving the accuracy of earthquake hazard assessments in other parts of the world. Their findings appear in the online journal Nature Communications.

According to the paper’s authors the Kaikoura earthquake is the most complicated ever recorded and raises a number of important questions. One of its most striking features was that it resulted in the successive of more than 20 segments of a network. “Looking at the pattern of surface faults affected by the quake, one finds large gaps of more than 15 km in between them. Up to now, analyses of seismic hazard have been based on the assumption that faults that are more than 5 km apart will not be broken in a single event,” says Gabriel. A second unusual observation was that, although the earthquake began on land, it also resulted in the largest tsunami recorded in the region since 1947. This indicates that the subsurface ruptures ultimately triggered local displacements of the seafloor.

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Two isolated mountain lion populations in southern California’s Santa Ana and Santa Monica Mountains are at risk of local extinction, perhaps as soon as within 50 years, according to a study published in the journal Ecological Applications.

The study showed the extinction risk is due to low genetic diversity and mortality that affects the stability of the population. Mountain mortality is often caused by humans, but can also result from changes in the environment, such as wildfire and fluctuations in prey density.

The two mountain lion populations in the human-dominated landscape of southern California are isolated by freeways and development. For the study, lead author John Benson of the University of Nebraska and co-authors at UCLA, the University of California, Davis, the National Park Service, the University of Washington, Northern Arizona University, and the University of Wyoming used population viability modeling to predict the possibilities of extinction from genetic and demographic risk factors.

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