54515649
submission
ckwu writes:
The vast real estate of windows in office buildings and skyscrapers could be a fruitful field for harvesting solar energy—if lightweight solar cells could be made with a high enough conversion efficiency and appealing aesthetics. Now researchers at Oxford University report semitransparent solar cells that might do the trick. The team made solar cells using a perovskite, a class of mineral-like materials that have properties similar to inorganic semiconductors and show sunlight-to-electricity conversion efficiencies of more than 15%. The team deposited a thin film of perovskite onto glass so that the material formed tiny crystalline islands. The islands absorb photons and convert them to electrons, while light striking the empty areas passes through. The result was a semitransparent solar cell with a grayish tint.
54439653
submission
MTorrice writes:
In recent years, increasing numbers of patients worldwide have contracted severe bacterial infections that are untreatable by most available antibiotics. Some of the gravest of these infections are caused by bacteria carrying genes that confer resistance to a broad class of antibiotics called beta-lactams, many of which are treatments of last resort. Now a research team reports that some wastewater treatment plants in China discharge one of these potent resistance genes into the environment. Environmental and public health experts worry that this discharge could promote the spread of resistance.
54401163
submission
MTorrice writes:
Curcumin, a natural compound found in turmeric, has shown promise as a potential treatment for Alzheimer’s disease but delivering it to the brain has been a challenge. Now researchers have packaged the compound inside polymer nanoparticles to help it get into the brain. For the first time, they’ve shown that this encapsulated curcumin can stimulate the production of neurons and improve memory in a rat model of Alzheimer’s disease.
53786363
submission
ckwu writes:
As a way to generate renewable electricity, researchers have designed methods that harvest the energy released when fresh and saline water mix, such as when a river meets the sea. One such method is called pressure-retarded osmosis, where two streams of water, one saline and one fresh, meet in a cell divided by a semipermeable membrane. Osmosis drives the freshwater across the membrane to the saltier side, increasing the pressure in the saline solution. The system keeps this salty water pressurized and then releases the pressure to spin a turbine to generate electricity. Now a team at Yale University has created a prototype device that increases the power output of pressure-retarded osmosis by an order of magnitude. At a full-scale facility, the estimated cost of the electricity generated by such a system could be 20 to 30 cents per kWh, approaching the cost of other conventional renewable energy technologies.
53421413
submission
carmendrahl writes:
Exposure to certain pesticides, including rotenone and paraquat, has been associated with a higher incidence of Parkinson's disease in population studies. But how did scientists come to think of a link between Parkinson's disease and pesticides in the first place? The answer involves the 1980s drug underworld, where criminals were synthesizing modified versions of illegal drugs such as heroin to stay one step ahead of the law. One molecule in some designer heroin cocktails, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), breaks down in the human body into 1-methyl-4-phenylpyridinium (MPP+), a nerve cell killer. Heroin addicts exposed to this molecule got Parkinson's-like symptoms. As for the connection to pesticides, MPP+ is a weed killer that was used in the 70s. It also closely resembles the structure of the pesticide paraquat. The saga, therefore, put scientists on high alert to the possibility that pesticides might play a role in developing Parkinson's.
53173425
submission
MTorrice writes:
To understand the brain and its chemical complexities, researchers would like to peer inside the skull and measure neurotransmitters levels as the brain at work. Unfortunately, research methods to measure levels of chemicals in the brain require drilling holes in the skull, and noninvasive imaging techniques, such as MRI, can’t detect specific molecules. Now, as a first step toward a new imaging tool, chemists report they can detect molecules hidden behind 3- to 8-mm-thick bone.
53106241
submission
MTorrice writes:
Competitive U.S. gymnasts can be exposed to high levels of flame retardants through the polyurethane foam padding used in gyms, according to a new study. Dust from these gyms contain concentrations of the chemicals that are one to three orders of magnitude greater than in homes. Also researchers drew blood from 11 college-level gymnasts and found levels of a potentially toxic brominated flame retardant in the athletes’ blood that were almost three times higher than those in the general population.
52921475
submission
MTorrice writes:
As wearable electronics move from abstract concepts to tangible products, engineers want to find ways to integrate flexible, powerful textile-based batteries into people's clothing to power the devices. Now researchers have built one of the most durable wearable batteries to date on polyester fabric. They electroplated nickel onto the polyester to produce electrodes that have high conductivity and can withstand repeated mechanical stress. The whole battery, which the researchers sewed into a hoody, can be folded 10,000 times without losing function.
52884065
submission
MTorrice writes:
With energy-efficient desalination techniques, water-starved communities could produce fresh water from salty sources such as seawater and industrial wastewater. But common methods like reverse osmosis require pumping the water, which uses a substantial amount of energy. So some researchers have turned to forward osmosis, because in theory it should use less energy. Now a team has demonstrated a forward osmosis system that desalinates salty water with the help of sunlight. The method uses a pair of hydrogels to absorb and squeeze out freshwater.
52036439
submission
MTorrice writes:
According to theoretical calculations, one-dimensional strings of carbon atoms called carbyne should be stronger than any known material—if experimentalists can figure out how to make it in bulk. Its tensile stiffness, for example, should be twice that of graphene and carbon nanotubes. The researchers predict that the carbon allotrope also could have novel electrical and magnetic properties that would be useful in computing systems.
51566769
submission
MTorrice writes:
Each year, tens of thousands of people with diabetes in the U.S. have a lower limb amputated because a small foot wound failed to heal. With diabetes rates on the rise, scientists are eagerly searching for effective treatments for the ulcers that develop from these unhealed wounds. Now, researchers have identified an enzyme that’s rampant in diabetic wounds and may interfere with healing. Inhibiting the enzyme accelerated wound healing in diabetic mice, suggesting a path to new drugs.
51479513
submission
ckwu writes:
Researchers in Japan and Taiwan have demonstrated the first working flash memory device made using proteins as scaffolding to build a 3-D nanoparticle structure. Compared to current fabrication techniques, using proteins to arrange nanoparticles could enable the design of smaller memory devices and more complex, multilayer electronics. According to the researchers, their mulitlayer flash memory had twice the capacity of a conventionally made single-layer device.
51392573
submission
MTorrice writes:
A new type of headphone heats up carbon nanotubes to crank out tunes. The tiny speaker doesn’t rely on moving parts and instead produces sound through the thermoacoustic effect. When an alternating current passes through the nanotubes, the material heats and cools the air around it; as the air warms, it expands, and as it cools, it contracts. This expansion and contraction creates sound waves. The new nanotube speaker could be manufactured at low cost in the same facilities used to make computer chips, the researchers say.
50973807
submission
MTorrice writes:
By attaching a lightweight, inexpensive device to the back of a smart phone, scientists can convert the phone into a sensitive fluorescence microscope. The attachment allows the phone’s camera to take pictures of single nanoparticles and viruses, possibly providing a portable diagnostic tool for health care workers in developing countries. For example, doctors in remote regions could use the technique to measure HIV viral loads in patients’ blood samples, allowing the doctors to easily monitor disease progression and determine the best course of treatment.
50924589
submission
MTorrice writes:
The same wells that energy companies drill to extract natural gas from shale formations could become repositories to store large quantities of carbon dioxide. A new computer model suggests that wells in the Marcellus shale, a 600-sq-mile formation in the northeastern U.S. that is a hotbed for gas extraction, could store half the CO2 emitted by the country’s power plants from now until 2030.
