73762191
submission
JMarshall writes:
Researchers have built a molecular nanocage 8 nm across that represents a step toward quantum computing.
It is difficult to make uniform nanoparticles more than 4 nm across, but new work solves this problem. Researchers made eight-membered metal rings from chromium and nickel that can act like a qubits in quantum computing. More connected rings means greater quantum computing capacity, so the team worked to combine many rings into one molecule. They managed to pull 24 rings together into an 8-nm sphere, secured by palladium ions at the core. The molecule had a surprisingly good phase memory, an indication of the molecule’s quantum computing potential. The researchers say building a molecule with 70-100 rings would allow them to do “some serious stuff” in quantum computing.
73697953
submission
JMarshall writes:
Researchers have made near-perfect reflectors out of a silicon metamaterial. These reflectors could offer a simpler, less expensive way to make high-performance mirrors for lasers or telescopes.
Metamaterials typically use nanoscale patterning to create unusual properties not present in the bulk material. In this new method, researchers used off-the-shelf, nanosized polystyrene beads and allowed them to self-assemble into a monolayer with a hexagonal pattern. Using the monolayer as a photolithographic mask, the researchers etched an array of silicon cylinders, each a few hundred nanometers across, onto a wafer. The cylinders act like tiny resonators for a particular light frequency—analogous to the way a given sound frequency will make a tuning fork hum. The array reflected 99.7 % of incident light at their peak wavelength. These simple metamaterial mirrors might one day replace current high-performance reflectors, which are somewhat costly to make.
73327405
submission
JMarshall writes:
Lithium-metal battery anodes can store 10-fold more energy by weight than those in today’s best batteries, but they have been too unstable to be practical. Now, researchers have used atomic layer deposition—widely used in the semiconductor industry—to coat lithium-metal anodes with a thin protective layer that dramatically improved their performance. Coated lithium-metal anodes did not corrode under conditions that corrode unprotected lithium metal. When combined with sulfur cathodes, which also have the potential to store lots of energy but which typically react badly with lithium, the lithium metal anodes performed well with no sign of degradation after 100 charge cycles. If these better batteries could be commercialized, they could allow electric vehicles to drive farther between charges or offer a more compact power source for implanted medical devices.
73261813
submission
MTorrice writes:
By adding a touch of cobalt to an alloy of titanium, nickel, and copper, an international team of researchers has come up with a shape-memory alloy film that can be deformed at least 10 million times and still snap back to its original shape. The finding represents a remarkable improvement on previous shape-memory alloys, which, at best, could withstand only a thousand deformations before succumbing to structural failure.
The current, top-of-class alloy is nickel titanium, which is used in stents to open blood vessels and as orthodontic wires.
73174779
submission
MTorrice writes:
Medical diagnostic devices that can be used in conjunction with a smartphone could allow health care workers to diagnose diseases or monitor a patient’s health on the spot, without the need to send off a sample to some remote laboratory. This, researchers say, could change the way people attend to their own health, putting a tool to monitor disease literally in their hands.
Such devices could also prove useful in the developing world, where smartphones are becoming common yet hospitals can be few and far between. In these regions, opportunities to diagnose easily treated disease are often missed. And for infectious diseases, such as influenza or Ebola virus, a point-of-care system combined with a smartphone’s ability to provide a geographical location could track a disease’s movement in real time and even identify and isolate patients to slow the spread of the disease.
73082775
submission
MTorrice writes:
An international research team has built electronic, flexible patches that can measure the mechanical properties of skin and other biological tissue. The sensors consist of nanoribbons of a piezoelectric material, lead zirconate titanate, which deforms when jolted with electrical energy and, conversely, produces electricity when it’s deformed. The researchers mapped the skin elasticity of dozens of patients in the clinic, building up quantitative data on healthy and damaged tissue. The information could help doctors better assess conditions such as dermatitis and skin cancer. The team believes that similar sensors could be implanted inside the body to monitor blood vessels and other soft tissue for damage or dysfunction.
72807061
submission
MTorrice writes:
Techniques that produce holograms have helped researchers create little lithium-ion batteries that could power microelectronic devices, such as sensors, medical implants, and radio frequency transmitters.
As engineers continue to shrink the size of electronics, they stoke a growing demand for miniaturized power supplies. Although researchers have already created millimeter-sized microbatteries, these generally fail to store sufficient energy or produce enough power for devices.
Engineers at the University of Illinois, Urbana-Champaign, recently demonstrated that porous, three-dimensional electrodes can boost a lithium-ion microbattery’s power output by three orders of magnitude. But the team, led by Paul V. Braun, lacked a simple, reliable way to optimize their electrode structure. Braun’s team has now used holograms, which are the 3-D interference patterns of multiple laser beams, to precisely create porous blocks in light-curable polymers. They then used these blocks as scaffolding to build electrodes.
72087719
submission
MTorrice writes:
Where once the use of Cannabis strains such as banana kush, Dr. Greenthumb’s ghost, and gorilla glue #4 was hidden behind closed doors, it is now increasingly in the open. Four states—Colorado, Washington, Alaska, and Oregon—have legalized both recreational and medicinal use, and another 19 allow medicinal use only. With that openness, however, comes new challenges in the form of safety concerns and evolving regulations to protect production workers and consumers. Companies are working on those issues, in particular finding ways to safely extract cannabinoids and other compounds from the plant material to yield concentrated oils and waxes used in vaporizers, foods, salves, or other products.
71899739
submission
MTorrice writes:
Oxytocin often gets hyped as the “love” hormone. But a new study suggests its role in the brain is a little more nuanced.
Through studies in people and animals, researchers have shown that oxytocin plays a critical role in many social behaviors, such as the building of trust between strangers and the bonding between mates. The new data demonstrate that oxytocin doesn’t directly increase trust or forge bonds, instead it enhances the strength of incoming social information. Basically, it tunes neural circuits to get more excited by social stimuli.
For example, the researchers looked at a behavior important in mother mice. When a mouse pup gets separated from its mother, it squeaks an ultrasonic distress signal. The mother hears these calls, and learns to bring the stray back to the nest. The team found that giving oxytocin to female mice that never had offspring allowed the virgin adults to quickly learn this maternal behavior.
When they examined neurons in the auditory cortices of virgin females, they found that the cells fired randomly in response to the squeaks before the oxytocin hit. After receiving the hormone, these neurons started to fire in a more regular pattern, similar to the cells in mother mouse brains.
The findings could lead to a better understanding of how the brain processes social information to guide behavior, possibly leading to therapies for mental disorders associated with social deficits, such as autism and psychopathy.
71340127
submission
MTorrice writes:
A foam composed of a polymer derived from crustacean shells may prevent more soldiers from falling victim to the most prolific killer on the battlefield: blood loss.
Pressure is one of the best tools that medics have to fight bleeding, but they can’t use it on severe wounds near organs. Here, compression could do more harm than good. First responders have no way to effectively dam blood flows from these noncompressible injuries, which account for the majority of hemorrhagic deaths. The new foam could help stop bleeding in these types of injuries.
It relies on chitosan, a biopolymer that comes from processed crustacean shells. By modifying the chitosan, the developers gave the material the ability to anchor blood cells into gel-like networks, essentially forming blood clots. The researchers dispersed the modified chitosan in water to create a fluid they could spray directly onto noncompressible wounds.
71339313
submission
BPariseau writes:
Listings for AWS jobs shed light on AWS roadmap plans, including new cost management tools, S3 improvements, database development and CloudFront.
71108799
submission
ckwu writes:
From bread bags to beverage bottles, many plastics now contain additives designed to make the materials biodegradable. But a new study shows that plastics made with such additives do not biodegrade in the environment significantly faster than those without the compounds. Researchers prepared films of commercial plastics with three different types of additives supplied by their manufacturers. The researchers then treated the film samples to mimic disposal of such plastics in a compost pile, a landfill, and soil. After about six months of composting, a year and a half of landfill-like conditions, and three years of soil burial, the plastics with additives did not show any more evidence of biodegradation than plastics without them.
70830409
submission
MTorrice writes:
A new study suggests a strategy to treat anxiety might be to design drugs that help the brain’s own regulatory circuitry kick in and tune down hyperactive neurons.
The study’s authors focus on a part of the brain that processes fear and other emotions—the amygdala. In people with anxiety disorders, the amygdala can become hyperactive, and one explanation for the elevated activity is disruption of endocannabinoid signaling. Endocannabinoids are lipids that hit the same brain receptors targeted by THC, the active chemical in marijuana. The greasy molecules help make sure nerve cells don't become overly excited or too lethargic.
In anxious mice, the researchers found the amygdala plays host to an overactive enzyme that disrupts endocannabinoid signaling. Inhibiting the unruly enzyme with a drug-like compound restores the circuit and stops anxious behavior in mice.
70485727
submission
MTorrice writes:
This year marks the 100th anniversary of the first large-scale use of chemical weapons during World War I. Sarah Everts at Chemical & Engineering News remembers the event with a detailed account of the day in 1915 when the German Army released chlorine gas on its enemies, igniting a chemical arms race. Read the diaries of soldiers involved in the first gas attack.
By the end of WWI, scientists working for both warring parties had evaluated some 3,000 different chemicals for use as weapons. Even though poison gas didn’t end up becoming an efficient killing weapon on WWI battlefields—it was responsible for less than 1% of WWI’s fatalities--its adoption set a precedent for using chemicals to murder en masse. In the past century, poison gas has killed millions of civilians around the world: commuters on the Tokyo subway, antigovernment demonstrators in Syria, and those incarcerated in Third Reich concentration camps. Everts profiles chemist Fritz Haber, the man who lobbied to unleash the gas that day in 1915.
69525989
submission
MTorrice writes:
The idea sounds like something out of a science-fiction novel: Tiny medical machines zooming around the body delivering drugs, taking tissue samples, or performing small surgical repairs. But, now, for the first time, researchers have demonstrated a simple micromotor that can propel itself inside the body. When introduced into a mouse’s stomach, the micromotor swims to the stomach lining and delivers cargo.
The motors are 20-micron-long, 5-micron-wide cylindrical tubes made from a biocompatible polymer and filled with zinc. The zinc reduces hydrogen ions to produce bubbles of hydrogen gas. Inside the stomachs of mice, the tubes react with ions in gastric acids to swim around and penetrate the mucus layer on the stomach surface.
