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Physicists have found “electron pairing,” a hallmark feature of superconductivity, at temperatures and energies well above the critical threshold where superconductivity happens.
Rice University’s Doug Natelson, co-corresponding author of a paper about the work in this week’s Nature, said the discovery of Cooper pairs of electrons “a bit above the critical temperature won’t be ‘crazy surprising’ to some people. The thing that’s more weird is that it looks like there are two different energy scales. There’s a higher energy scale where the pairs form, and there’s a lower energy scale where they all decide to join hands and act collectively and coherently, the behavior that actually brings about superconductivity.”
Continue reading “‘Electron pairing’ found well above superconductor’s critical temperature” »
A research team led by the University of California San Diego has discovered the root cause of why lithium metal batteries fail—bits of lithium metal deposits break off from the surface of the anode during discharging and are trapped as “dead” or inactive lithium that the battery can no longer access.
The discovery, published Aug. 21 in Nature, challenges the conventional belief that lithium metal batteries fail because of the growth of a layer, called the solid electrolyte interphase (SEI), between the lithium anode and the electrolyte. The researchers made their discovery by developing a technique to measure the amounts of inactive lithium species on the anode—a first in the field of battery research—and studying their micro- and nanostructures.
The findings could pave the way for bringing rechargeable lithium metal batteries from the lab to the market.
The ability to securely transmit information over the internet is extremely important, but most of the time, eavesdroppers can still generally determine who the sender and receiver are. In some highly confidential situations, it is important that the sender’s and receiver’s identities remain anonymous.
Over the past couple of decades, researchers have been developing protocols for anonymously transmitting messages over classical networks, but similar protocols for quantum networks are still in much earlier stages of development. The anonymity methods that have been proposed for quantum networks so far face challenges such as implementation difficulties or require that strong assumptions be made about the resources, making them impractical for use in the real world.
In a new paper, Anupama Unnikrishnan, Ian MacFarlane, Richard Yi, Eleni Diamanti, Damian Markham, and Iordanis Kerenidis, from the University of Oxford, MIT, Sorbonne University, the University of Paris and CNRS, have proposed the first practical protocol for anonymous communication in quantum networks.
Self-assembled materials are attractive for next-generation materials, but their potential to assemble at the nanoscale and form nanostructures (cylinders, lamellae etc.) remains challenging. In a recent report, Xundu Feng and colleagues at the interdisciplinary departments of chemical and environmental engineering, biomolecular engineering, chemistry and the center for advanced low-dimension materials in the U.S., France, Japan and China, proposed and demonstrated a new approach to prevent the existing challenges. In the study, they explored size-selective transport in the water-continuous medium of a nanostructured polymer template formed using a self-assembled lyotropic H1 (hexagonal cylindrical shaped) mesophase (a state of matter between liquid and solid). They optimized the mesophase composition to facilitate high-fidelity retention of the H1 structure on photoinduced crosslinking.
The resulting nanostructured polymer material was mechanically robust with internally and externally crosslinked nanofibrils surrounded by a continuous aqueous medium. The research team fabricated a membrane with size selectivity at the 1 to 2 nm length scale and water permeabilities of ~10 liters m−2 hour−1 bar−1 μm. The membranes displayed excellent anti-microbial properties for practical use. The results are now published on Science Advances and represent a breakthrough for the potential use of self-assembled membrane-based nanofiltration in practical applications of water purification.
Membrane separation for filtration is widely used in diverse technical applications, including seawater desalination, gas separation, food processing, fuel cells and the emerging fields of sustainable power generation and distillation. During nanofiltration, dissolved or suspended solutes ranging from 1 to 10 nm in size can be removed. New nanofiltration membranes are of particular interest for low-cost treatment of wastewaters to remove organic contaminants including pesticides and metabolites of pharmaceutical drugs. State-of-the-art membranes presently suffer from a trade-off between permeability and selectivity where increased permeability can result in decreased selectivity and vice-versa. Since the trade-off originated from the intrinsic structural limits of conventional membranes, materials scientists have incorporated self-assembled materials as an attractive solution to realize highly selective separation without compromising permeability.
(BICA for AI, Post Conference Journal Paper, see Springer)
Abstract:
This paper is focused on preliminary cognitive and consciousness test results from using an Independent Core Observer Model Cognitive Architecture (ICOM) in a Mediated Artificial Super Intelligence (mASI) System. These results, including objective and subjective analyses, are designed to determine if further research is warranted along these lines. The comparative analysis includes comparisons to humans and human groups as measured for direct comparison. The overall study includes a mediation client application optimization in helping perform tests, AI context-based input (building context tree or graph data models), intelligence comparative testing (such as an IQ test), and other tests (i.e. Turing, Qualia, and Porter method tests) designed to look for early signs of consciousness or the lack thereof in the mASI system. Together, they are designed to determine whether this modified version of ICOM is a) in fact, a form of AGI and/or ASI, b) conscious, and c) at least sufficiently interesting that further research is called for. This study is not conclusive but offers evidence to justify further research along these lines.
Any future colonization efforts directed at the Mars all share one problem in common; their reliance on a non-existent magnetic field. Mars’ magnetosphere went dark about 4 billion years ago when it’s core solidified due to its inability to retain heat because of its small mass. We now know that Mars was quite Earth-like in its history. Deep oceans once filled the now arid Martian valleys and a thick atmosphere once retained gasses which may have allowed for the development of simple life. This was all shielded by Mars’ prehistoric magnetic field.
When Mars’ magnetic line of defense fell, much of its atmosphere was ripped away into space, its oceans froze deep into the red regolith, and any chance for life to thrive there was suffocated. The reduction of greenhouse gasses caused Mars’ temperature to plummet, freezing any remaining atmosphere to the poles. Today, Mars is all but dead. Without a magnetic field, a lethal array of charged particles from the Sun bombards Mars’ surface every day threatening the potential of hosting electronic systems as well as biological life. The lack of a magnetic field also makes it impossible for Mars to retain an atmosphere or an ozone layer, which are detrimental in filtering out UV and high energy light. This would seem to make the basic principles behind terraforming the planet completely obsolete.
I’ve read a lot of articles about the potential of supplying Mars with an artificial magnetic field. By placing a satellite equipped with technology to produce a powerful magnetic field at Mars L1 (a far orbit around Mars where gravity from the Sun balances gravity from Mars, so that the satellite always remains between Mars and the Sun), we could encompass Mars in the resulting magnetic sheath. However, even though the idea is well understood and written about, I couldn’t find a solid mathematical proof of the concept to study for actual feasibility. So I made one!
An international team of researchers with partial support from the National Institute of Biomedical Imaging and Bioengineering (NIBIB) developed a new MRI technique that can capture an image of a brain thinking by measuring changes in tissue stiffness. The results show that brain function can be tracked on a time scale of 100 milliseconds – 60 times faster than previous methods. The technique could shed new light on altered neuronal activity in brain diseases.
The human brain responds almost immediately to stimuli, but non-invasive imaging techniques haven’t been able to keep pace with the brain. Currently, several non-invasive brain imaging methods measure brain function, but they all have limitations. Most commonly, clinicians and researchers use functional magnetic resonance imaging (fMRI) to measure brain activity via fluctuations in blood oxygen levels. However, a lot of vital brain activity information is lost using fMRI because blood oxygen levels take about six seconds to respond to a stimulus.
Since the mid-1990s, researchers have been able to generate maps of tissue stiffness using an MRI scanner, with a non-invasive technique called magnetic resonance elastography (MRE). Tissue stiffness can’t be measured directly, so instead researchers use MRE to measure the speed at which mechanical vibrations travel through tissue. Vibrations move faster through stiffer tissues, while vibrations travel through softer tissue more slowly; therefore, tissue stiffness can be determined. MRE is most commonly used to detect the hardening of liver tissue but has more recently been applied to other tissues like the brain.
Astronomers have announced a discovery which may have an essential effect on life on the planet Earth. Another planetary system, which is comprised of planets with the size of our planet, which could probably have water on them and in that way, life too.
Nowadays, scientists that work using telescopes at NASA and the European Southern Observatory announced their astonishing discovery – a whole system of planets with the size of the planet Earth. Well, if this is not enough, this team also claims that the planets’ density measurements indicate that six of them, which are more central, are rocky worlds like our planet.
Continue reading “NASA Found An Entire Solar System With 7 Earth-Like Planets” »
Stellarators, twisty machines that house fusion reactions, rely on complex magnetic coils that are challenging to design and build. Now, a physicist at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) has developed a mathematical technique to help simplify the design of the coils, making stellarators a potentially more cost-effective facility for producing fusion energy.
“Our main result is that we came up with a new method of identifying the irregular magnetic fields produced by stellarator coils,” said physicist Caoxiang Zhu, lead author of a paper reporting the results in Nuclear Fusion. “This technique can let you know in advance which coil shapes and placements could harm the plasma’s magnetic confinement, promising a shorter construction time and reduced costs.”
Fusion, the power that drives the sun and stars, is the fusing of light elements in the form of plasma—the hot, charged state of matter composed of free electrons and atomic nuclei—that generates massive amounts of energy. Twisty, cruller-shaped stellarators are an alternative to doughnut-shaped tokamaks that are more commonly used by scientists seeking to replicate fusion on Earth for a virtually inexhaustible supply of power to generate electricity.
