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Archive for the ‘computing’ category: Page 353

Dec 13, 2020

Bullets bounce off nanotubes

Posted by in categories: computing, nanotechnology

Circa 2007


Robocops could soon leave the realm of science fiction thanks to a new bullet-proof material proposed by engineers in Australia. According to computer simulations done by the team, bullets would be no match for vests made of the material, and would simply bounce off owing to the high elasticity of the nanotubes. The researchers claim that the material, which has not been made yet, would be a great improvement on existing anti-ballistic clothing that stop bullets from penetrating by spreading the bullet’s force — something that can still cause serious injury (Nanotechnology 18 475701).

Dec 13, 2020

3D vortex rings appear in a bulk magnet

Posted by in categories: computing, materials

Researchers have observed three-dimensional magnetic vortex rings in a real-world magnetic material for the first time. Contrary to theoretical predictions, these rings – which are spin configurations within the material’s bulk – are remarkably stable and could move through the material like smoke rings move through air. If such movement can be controlled, they might have applications in energy-efficient 3D data storage and processing.

In a ferromagnetic material, the spatial distribution of the local magnetization is responsible for the material’s magnetic properties. These spatial distributions can be very complex, and intricate magnetic “textures” are behind many modern technologies, including hard disk drives. A vortex is one such distribution, and it forms when the material’s magnetization circulates around a central core.

Vortex rings are more sophisticated still, and occur naturally in physical systems such as fluids, plasmas and turbulent gases in the Earth’s atmosphere. However, while they have long been predicted to exist in ferromagnets, they have never been observed there until now.

Dec 13, 2020

Danish researchers developed nanochip that could achieve ‘quantum supremacy’

Posted by in categories: computing, quantum physics

Specialists from the University of Copenhagen created a chip that could be used to build a future quantum simulator.

Dec 13, 2020

How Can We Fall Asleep More Easily? Neuralink 2021 And Beyond [Part 2]

Posted by in categories: computing, neuroscience

Hey it’s Han from WrySci HX with Part 2 of a four part series on sleep and brain computer interfaces such as Neuralink. We’ll look at what we know about sleep and how BCIs might be able to help us in the future, 2021 and beyond. This isn’t a topic I’ve seen much about so I decided to see what was up. This second part is on sleep regulation (aka how we fall asleep, and hopefully how we can fall asleep more easily in the future) and sleeping with only certain parts of the brain, while the next ones will cover sleep and dream theories. More below ↓↓↓

Watch Part 1 here! https://youtu.be/EmtlanXdGf4

Continue reading “How Can We Fall Asleep More Easily? Neuralink 2021 And Beyond [Part 2]” »

Dec 12, 2020

Proving the Existence of the Quark-Gluon Plasma With Gravitational Waves

Posted by in categories: computing, particle physics, space

Computer models of merging neutron stars predicts new signature in the gravitational waves to tell when this happens.

Neutron stars are among the densest objects in the universe. If our Sun, with its radius of 700,000 kilometers were a neutron star, its mass would be condensed into an almost perfect sphere with a radius of around 12 kilometers. When two neutron stars collide and merge into a hyper-massive neutron star, the matter in the core of the new object becomes incredibly hot and dense. According to physical calculations, these conditions could result in hadrons such as neutrons and protons, which are the particles normally found in our daily experience, dissolving into their components of quarks and gluons and thus producing a quark-gluon plasma.

Continue reading “Proving the Existence of the Quark-Gluon Plasma With Gravitational Waves” »

Dec 12, 2020

Genetic engineering transformed stem cells into working mini-livers that extended the life of mice with liver disease

Posted by in categories: bioengineering, biotech/medical, chemistry, computing, food, genetics, life extension, neuroscience

Takeaways * Scientists have made progress growing human liver in the lab. * The challenge has been to direct stems cells to grow into a mature, functioning adult organ. * This study shows that stem cells can be programmed, using genetic engineering, to grow from immature cells into mature tissue. * When a tiny lab-grown liver was transplanted into mice with liver disease, it extended the lives of the sick animals.* * *Imagine if researchers could program stem cells, which have the potential to grow into all cell types in the body, so that they could generate an entire human organ. This would allow scientists to manufacture tissues for testing drugs and reduce the demand for transplant organs by having new ones grown directly from a patient’s cells. I’m a researcher working in this new field – called synthetic biology – focused on creating new biological parts and redesigning existing biological systems. In a new paper, my colleagues and I showed progress in one of the key challenges with lab-grown organs – figuring out the genes necessary to produce the variety of mature cells needed to construct a functioning liver. Induced pluripotent stem cells, a subgroup of stem cells, are capable of producing cells that can build entire organs in the human body. But they can do this job only if they receive the right quantity of growth signals at the right time from their environment. If this happens, they eventually give rise to different cell types that can assemble and mature in the form of human organs and tissues. The tissues researchers generate from pluripotent stem cells can provide a unique source for personalized medicine from transplantation to novel drug discovery. But unfortunately, synthetic tissues from stem cells are not always suitable for transplant or drug testing because they contain unwanted cells from other tissues, or lack the tissue maturity and a complete network of blood vessels necessary for bringing oxygen and nutrients needed to nurture an organ. That is why having a framework to assess whether these lab-grown cells and tissues are doing their job, and how to make them more like human organs, is critical. Inspired by this challenge, I was determined to establish a synthetic biology method to read and write, or program, tissue development. I am trying to do this using the genetic language of stem cells, similar to what is used by nature to form human organs. Tissues and organs made by genetic designsI am a researcher specializing in synthetic biology and biological engineering at the Pittsburgh Liver Research Center and McGowan Institute for Regenerative Medicine, where the goals are to use engineering approaches to analyze and build novel biological systems and solve human health problems. My lab combines synthetic biology and regenerative medicine in a new field that strives to replace, regrow or repair diseased organs or tissues. I chose to focus on growing new human livers because this organ is vital for controlling most levels of chemicals – like proteins or sugar – in the blood. The liver also breaks down harmful chemicals and metabolizes many drugs in our body. But the liver tissue is also vulnerable and can be damaged and destroyed by many diseases, such as hepatitis or fatty liver disease. There is a shortage of donor organs, which limits liver transplantation. To make synthetic organs and tissues, scientists need to be able to control stem cells so that they can form into different types of cells, such as liver cells and blood vessel cells. The goal is to mature these stem cells into miniorgans, or organoids, containing blood vessels and the correct adult cell types that would be found in a natural organ. One way to orchestrate maturation of synthetic tissues is to determine the list of genes needed to induce a group of stem cells to grow, mature and evolve into a complete and functioning organ. To derive this list I worked with Patrick Cahan and Samira Kiani to first use computational analysis to identify genes involved in transforming a group of stem cells into a mature functioning liver. Then our team led by two of my students – Jeremy Velazquez and Ryan LeGraw – used genetic engineering to alter specific genes we had identified and used them to help build and mature human liver tissues from stem cells. The tissue is grown from a layer of genetically engineered stem cells in a petri dish. The function of genetic programs together with nutrients is to orchestrate formation of liver organoids over the course of 15 to 17 days. Liver in a dishI and my colleagues first compared the active genes in fetal liver organoids we had grown in the lab with those in adult human livers using a computational analysis to get a list of genes needed for driving fetal liver organoids to mature into adult organs. We then used genetic engineering to tweak genes – and the resulting proteins – that the stem cells needed to mature further toward an adult liver. In the course of about 17 days we generated tiny – several millimeters in width – but more mature liver tissues with a range of cells typically found in livers in the third trimester of human pregnancies. Like a mature human liver, these synthetic livers were able to store, synthesize and metabolize nutrients. Though our lab-grown livers were small, we are hopeful that we can scale them up in the future. While they share many similar features with adult livers, they aren’t perfect and our team still has work to do. For example, we still need to improve the capacity of the liver tissue to metabolize a variety of drugs. We also need to make it safer and more efficacious for eventual application in humans.[Deep knowledge, daily. Sign up for The Conversation’s newsletter.]Our study demonstrates the ability of these lab livers to mature and develop a functional network of blood vessels in just two and a half weeks. We believe this approach can pave the path for the manufacture of other organs with vasculature via genetic programming. The liver organoids provide several key features of an adult human liver such as production of key blood proteins and regulation of bile – a chemical important for digestion of food. When we implanted the lab-grown liver tissues into mice suffering from liver disease, it increased the life span. We named our organoids “designer organoids,” as they are generated via a genetic design. This article is republished from The Conversation, a nonprofit news site dedicated to sharing ideas from academic experts. It was written by: Mo Ebrahimkhani, University of Pittsburgh. Read more: * Brain organoids help neuroscientists understand brain development, but aren’t perfect matches for real brains * Why are scientists trying to manufacture organs in space?Mo Ebrahimkhani receives funding from National Institute of Health, University of Pittsburgh and Arizona Biomedical Research Council.

Dec 12, 2020

Energy-efficient magnetic RAM: A new building block for spintronic technologies

Posted by in categories: computing, particle physics

Researchers at Pohang University of Science and Technology (POSTECH) and Seoul National University in South Korea have demonstrated a new way to enhance the energy efficiency of a non-volatile magnetic memory device called SOT-MRAM. Published in Advanced Materials, this finding opens up a new window of exciting opportunities for future energy-efficient magnetic memories based on spintronics.

In modern computers, the (RAM) is used to store information. The SOT-MRAM (spin-orbit torque magnetic RAM) is one of the leading candidates for the next-generation memory technologies that aim to surpass the performance of various existing RAMs. The SOT-MRAM may operate faster than the fastest existing RAM (SRAM) and maintain information even after the electric is powered off whereas all fast RAMs existing today lose information as soon as the supply is powered off. The present level of the SOT-MRAM technology falls short of being satisfactory, however, due to its high energy demand; it requires large energy supply (or large current) to write information. Lowering the energy demand and enhancing the energy efficiency is an outstanding problem for the SOT-MRAM.

In the SOT-MRAM, magnetization directions of tiny magnets store information and writing amounts to change the magnetization directions to desired directions. The magnetization direction change is achieved by a special physics phenomenon called SOT that modifies the magnetization direction when a current is applied. To enhance the energy efficiency, soft magnets are ideal material choice for the tiny magnets since their magnetization directions can be easily alterned by a small current. Soft magnets are bad choice for the safe storage of information since their magnetization direction may be altered even when not intended—due to thermal noise or other noise. For this reason, most attempts to build the SOT-MRAM adopt hard magnets, because they magnetize very strongly and their magnetization direction is not easily altered by noise. But this material choice inevitably makes the energy efficiency of the SOT-MRAM poor.

Dec 11, 2020

Scientists suggest US embassies were hit with high-power microwaves – here’s how the weapons work

Posted by in categories: biotech/medical, computing, military

The mystery ailment that has afflicted U.S. embassy staff and CIA officers off and on over the last four years in Cuba, China, Russia and other countries appears to have been caused by high-power microwaves, according to a report released by the National Academies. A committee of 19 experts in medicine and other fields concluded that directed, pulsed radiofrequency energy is the “most plausible mechanism” to explain the illness, dubbed Havana syndrome.

The report doesn’t clear up who targeted the embassies or why they were targeted. But the technology behind the suspected weapons is well understood and dates back to the Cold War arms race between the U.S. and the Soviet Union. High-power microwave weapons are generally designed to disable electronic equipment. But as the Havana syndrome reports show, these pulses of energy can harm people, as well.

Continue reading “Scientists suggest US embassies were hit with high-power microwaves – here’s how the weapons work” »

Dec 11, 2020

Physicists use antiferromagnetic rust to carry information over long distances at room temperature

Posted by in categories: computing, mobile phones, particle physics, quantum physics

Be it with smartphones, laptops, or mainframes: The transmission, processing, and storage of information is currently based on a single class of material—as it was in the early days of computer science about 60 years ago. A new class of magnetic materials, however, could raise information technology to a new level. Antiferromagnetic insulators enable computing speeds that are a thousand times faster than conventional electronics, with significantly less heating. Components could be packed closer together and logic modules could thus become smaller, which has so far been limited due to the increased heating of current components.

Information transfer at room temperature

So far, the problem has been that the information transfer in antiferromagnetic insulators only worked at low temperatures. But who wants to put their smartphones in the freezer to be able to use it? Physicists at Johannes Gutenberg University Mainz (JGU) have now been able to eliminate this shortcoming, together with experimentalists from the CNRS/Thales lab, the CEA Grenoble, and the National High Field Laboratory in France as well as theorists from the Center for Quantum Spintronics (QuSpin) at the Norwegian University of Science and Technology. “We were able to transmit and process information in a standard antiferromagnetic insulator at room temperature—and to do so over long enough distances to enable information processing to occur”, said JGU scientist Andrew Ross. The researchers used iron oxide (α-Fe2O3), the main component of rust, as an antiferromagnetic , because iron oxide is widespread and easy to manufacture.

Dec 11, 2020

Apple is now building the chip it needs to ditch Qualcomm like it ditched Intel

Posted by in category: computing

Apple modems are coming.


Would an Apple modem be better, or just less reliance on Qualcomm?