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Jul 7, 2020
Shock-dissipating fractal cubes could forge high-tech armor
Posted by Quinn Sena in categories: 3D printing, materials
Tiny, 3D printed cubes of plastic, with intricate fractal voids built into them, have proven to be effective at dissipating shockwaves, potentially leading to new types of lightweight armor and structural materials effective against explosions and impacts.
“The goal of the work is to manipulate the wave interactions resulting from a shockwave,” said Dana Dattelbaum, a scientist at Los Alamos National Laboratory and lead author on a paper to appear in the journal AIP Advances. “The guiding principles for how to do so have not been well defined, certainly less so compared to mechanical deformation of additively manufactured materials. We’re defining those principles, due to advanced, mesoscale manufacturing and design.”
Shockwave dispersing materials that take advantage of voids have been developed in the past, but they typically involved random distributions discovered through trial and error. Others have used layers to reverberate shock and release waves. Precisely controlling the location of holes in a material allows the researchers to design, model and test structures that perform as designed, in a reproducible way.
Jul 7, 2020
‘Light squeezer’ reduces quantum noise in lasers, could enhance quantum computing and gravitational-wave detection
Posted by Quinn Sena in categories: computing, quantum physics
Physicists at MIT have designed a quantum “light squeezer” that reduces quantum noise in an incoming laser beam by 15 percent. It is the first system of its kind to work at room temperature, making it amenable to a compact, portable setup that may be added to high-precision experiments to improve laser measurements where quantum noise is a limiting factor.
The heart of the new squeezer is a marble-sized optical cavity, housed in a vacuum chamber and containing two mirrors, one of which is smaller than the diameter of a human hair. The larger mirror stands stationary while the other is movable, suspended by a spring-like cantilever.
The shape and makeup of this second “nanomechanical” mirror is the key to the system’s ability to work at room temperature. When a laser beam enters the cavity, it bounces between the two mirrors. The force imparted by the light makes the nanomechanical mirror swing back and forth in a way that allows the researchers to engineer the light exiting the cavity to have special quantum properties.
Jul 7, 2020
Team obtained high-level control of spin qubit lifetime based on silicon quantum dots
Posted by Quinn Sena in categories: computing, quantum physics
By tuning the direction of the external magnetic field with respect to the crystallographic axis of the silicon wafer, an improvement of spin lifetime (relaxation time) by over two orders of magnitude was reported in silicon quantum dots. This breakthrough was carried out by a team led by academician Guo Guangcan from CAS Key Laboratory of Quantum Information, USTC, in which Prof. Guo Guoping, Prof. Li Hai-Ou with their colleagues and Origin Quantum Computing Company Limited. This work was published in Physical Review Letters on June 23, 2020.
Spin qubits based on silicon quantum dots have been a core issue in the development of large scale quantum computation due to its long coherence time and the compatibility with modern semiconductor technology. Recently, the relaxation time and dephasing time of spin qubits developed in Si MOS (Metal-Oxide-Semiconductor) and Si/SiGe heterostructure have surpassed hundreds of milliseconds and hundreds of microseconds, respectively, resulting in a single-qubit control fidelity over 99.9% and a two-qubit gate fidelity over 98%. With the success in college, labs and companies from the industry are starting to be involved in this field, such as Intel, CEA-Leti, and IMEC. However, the existence of valley states (a state associated with the dip in a particular electronic band) in silicon quantum dots could reduce spin relaxation time and dephasing time seriously via spin-valley mixing and limit the control fidelity of qubits.
Jul 7, 2020
First studies from largest-ever human genome database released
Posted by Quinn Sena in categories: biotech/medical, genetics
The Genome Aggregation Database has collected 15,708 genomes and 125,748 exomes (the protein-coding part of the genome) to help shed light on how genetic mutations can lead to disease. Dr Daniel MacArthur, scientific lead of the gnomAD Project, explains how the project started, how they collect the data and what they hope to achieve.
Jul 7, 2020
Atlantic Coast Pipeline Canceled Following Years of Legal Challenges
Posted by Quinn Sena in categories: climatology, health, law
Pipeline owners Dominion and Duke Energy announced Sunday they were cancelling the fossil fuel project due to mounting delays and uncertainty. They said the many legal challenges to the project had driven up the projected costs by almost half, from $4.5 to $5 billion when it was first announced in 2014 to $8 billion according to the most recent estimate.
Environmental and community groups, who have long opposed the project on climate, conservation and racial justice grounds, welcomed the news.
Continue reading “Atlantic Coast Pipeline Canceled Following Years of Legal Challenges” »
Jul 7, 2020
High Blood Pressure May Lead to Low Brain Volume
Posted by Genevieve Klien in categories: biotech/medical, neuroscience
Having hypertension in midlife (ages 40 through 60) is associated with elevated risk of cognitive impairment and Alzheimer’s dementia later in life, even more so than having the so-called Alzheimer’s gene.
“It is clear that cerebral vascular disease”—that is, hardening of the arteries inside our brain—“and cognitive decline travel hand in hand,” something I’ve addressed before. “However, the independent association of AD [Alzheimer’s disease] with multiple AVD [atherosclerotic vascular disease] risk factors suggests that cholesterol is not the sole culprit in dementia.”
As I discuss in my video Higher Blood Pressure May Lead to Brain Shrinkage, one of the most consistent findings is that elevated levels of blood pressure in midlife, ages 40 through 60, is associated with elevated risk of cognitive impairment and Alzheimer’s dementia later in life—in fact, even more so than having the so-called Alzheimer’s gene.
Jul 7, 2020
More Humanin Increases Chances for Healthier Living to 100
Posted by Kevin Huang in categories: biotech/medical, life extension
Jul 7, 2020
Fighting Antibody Cocktail Being Tested in Thousands of People
Posted by Lon Anderson in category: biotech/medical
An antibody cocktail designed to prevent and treat COVID-19 is now entering late-stage clinical trials, according to reports.
When naturally infected with COVID-19, the body generates Y-shaped molecules called antibodies that latch onto the virus and mark it for destruction, or hinder its ability to infect healthy cells, Live Science previously reported. These antibodies can be drawn from recovered COVID-19 patients and injected into sick patients to bolster their immune systems against the virus, a treatment known as convalescent plasma therapy.