Tech

Solar flares, cosmic radiation, and the northern lights are well known phenomena. But exactly how their enormous energy arises is not as well understood.

Now, physicists at Chalmers University of Technology, Sweden, have discovered a new way to study these spectacular space plasma phenomena in a laboratory environment. The results have been published in the renowned journal Nature Communications.

"Scientists have been trying to bring these space phenomena down to earth for a decade. With our new method we can enter a new era, and investigate what was previously impossible to study. It will tell us more about how these events occur," says Longqing Yi, researcher at the Department of Physics at Chalmers.

The research concerns so-called 'magnetic reconnection' - the process which gives rise to these phenomena. Magnetic reconnection causes sudden conversion of energy stored in the magnetic field into heat and kinetic energy. This happens when two plasmas with anti-parallel magnetic fields are pushed together, and the magnetic field lines converge and reconnect. This interaction leads to violently accelerated plasma particles that can sometimes be seen with the naked eye - for example, during the northern lights.

Magnetic reconnection in space can also influence us on earth. The creation of solar flares can interfere with communications satellites, and thus affect power grids, air traffic and telephony.

In order to imitate and study these spectacular space plasma phenomena in the laboratory, you need a high-power laser, to create magnetic fields around a million times stronger than those found on the surface of the sun. In the new scientific article, Longqing Yi, along with Professor Tünde Fülöp from the Department of Physics, proposed an experiment in which magnetic reconnection can be studied in a new, more precise way. Through the use of grazing incidence of ultra-short laser pulses, the effect can be achieved without overheating the plasma. The process can thus be studied very cleanly, without the laser directly affecting the internal energy of the plasma.

The proposed experiment would therefore allow us to seek answers to some of the most fundamental questions in astrophysics.

"We hope that this can inspire many research groups to use our results. This is a great opportunity to look for knowledge that could be useful in a number of areas. For example, we need to better understand solar flares, which can interfere with important communication systems. We also need to be able to control the instabilities caused by magnetic reconnection in fusion devices," says Tünde Fülöp.

The study on which the new results are based was financed by the Knut and Alice Wallenberg foundation, through the framework of the project 'Plasma-based Compact Ion Sources', and the ERC project 'Running away and radiating'.

Have you thanked a crop breeder today?

Public-sector plant breeders (for example, at public universities) have developed crops for better productivity. As a result, more food is available to feed a growing population.

This research and innovation requires funding. But funding--and revenue from the crops developed--is increasingly hard to obtain.

In response, a group of plant breeders met in 2016 to discuss best practices. Julie Dawson, an assistant professor at the University of Wisconsin-Madison, is lead author of a recent paper summarizing their recommendations.

Intellectual property rights can protect crop varieties. And licensing can provide revenue to support further developments. But certain types of intellectual property rights can restrict plant breeders from sharing plant materials. That can limit innovation across the board.

Finding a balance between these needs is tricky. It's also important: "Crop breeding is critical for the future of agriculture," says Dawson. "Plant breeding programs benefit farmers everywhere. They also benefit anyone who eats."

The group has three recommendations. They suggest developing best practices for revenue sharing. They advocate for increased funding for public programs. They also suggest establishing professional standards for sharing plant breeding materials.

Historically, many crop varieties were released to the public with almost no restrictions. "But budgets are getting tighter," says Dawson. "Grant funding is also becoming more competitive. Public sector plant breeders need to seek other sources of revenue."

Royalties generated by licensing new crop varieties have been one revenue stream. These royalties are usually shared between universities and their plant breeding programs. But the group finds that the distribution isn't always equitable.

"Cultivar development can be considered a type of university-sponsored start-up," Dawson says. "In order to continue the breeding programs a reasonable amount of revenue needs to be returned to those programs. Unfortunately, the workgroup found this is not always the case."

Overall funding for public plant breeding programs also needs to increase, according to the group. Public breeding programs train the next generation of researchers and plant breeders. They can also focus on low-return, high-value crops that are less attractive to the private sector.

For example, cover crops may have relatively low monetary returns. That can reduce interest from the private sector. But they have high social or environmental value, such as improving soil quality or reducing erosion.

"Public programs don't have to be immediately profitable, unlike in the private sector," says Dawson. "The public sector is able to respond to regional and long-term needs of U.S. agriculture," says Dawson. "It can do so in ways that are more difficult for private companies that need to turn a profit every year."

The group also advocates for uniform standards for sharing breeding materials. They recommend using the Wheat Workers' Code of Ethics as a template. Crop breeders could then work with their universities to better define intellectual property rights and sharable resources.

"Tech transfer offices are usually more familiar with medical or engineering innovations," says Dawson. "Plant breeders need existing plant material to continue innovating. Restrictive intellectual property rights can shut off this source of research materials. That essentially turns each breeding program into a silo and hinders innovation."

PROVIDENCE, R.I. [Brown University] --Good news, vegans: A new study finds that kimchi made without fish products has the same type of bacteria as more traditionally made kimchi. That finding suggests that any "probiotic" benefits associated with traditional kimchi could be present in vegan versions as well.

Along with other fermented foods like yogurt and kombucha, kimchi is surging in popularity as a probiotic food -- one that contains the same kinds of healthy bacteria found in the human gut. A traditional Korean side dish, kimchi consists mainly of fermented cabbage, radish and other vegetables. But it's normally made using fish sauce, fish paste or other seafood. That takes it off the menu for vegans, who don't eat any products derived from animals. But in order to appeal to vegan consumers, some producers have begun making a vegan alternative to traditional kimchi.

"In vegan kimchi, producers swap in things like miso, which is a fermented soybean paste, in place of the seafood components," said Michelle Zabat, an undergraduate at Brown University and lead author of the study, which is published in the journal Food Microbiology. "We wanted to know what the effects of making that swap might be in terms of the microbial community that's produced during fermentation."

Working in the lab of Peter Belenky, an assistant professor of molecular microbiology and immunology at Brown, Zabat partnered with Chi Kitchen, a Pawtucket, R.I.-based company that makes both traditional and vegan kimchi. The researchers took bacterial samples from the starting ingredients of both kinds of kimchi, as well as samples during the fermentation process and from the final products. The team took additional environmental samples from the factory, including from production tables, sinks and floors. The researchers then used high-throughput DNA sequencing to identify the types of bacteria present.

The study showed that the vegan and traditional kimchi ingredients had very different microbial communities to start, but over the course of fermentation the communities quickly became more similar. By the time fermentation was complete, the two communities were nearly identical. Both were dominated by lactobacillus and leuconostoc, genuses well known to thrive in fermented cabbage. Those bacteria were present only in small amounts in the starting ingredients for both products, the researchers found, yet were the only bacteria to survive the fermentation environment.

That's not exactly what the researchers expected to see.

"Miso has a lot of live bacteria in it at the start," Belenky said. "The fact that those bacteria were lost almost immediately during the fermentation was surprising. We thought they'd carry over to the kimchi, but they didn't."

That's likely because bacteria found in the miso thrive in extremely salty environments, and the kimchi isn't quite salty enough for them. "If we made really salty kimchi," Belenky said, "we might see them."

The study looked at only one brand of kimchi, and it's not a sure thing that the findings will to the same for other brands. In fact, researchers point out that the microbial community that dominated the kimchi they tested closely matched the community in samples taken from the production facility. It's not clear from this study whether those bacteria in the environment came from the kimchi or the other way around. It's possible, the researchers say, that the facility provided a "starter culture" that influences the eventual microbial community in the kimchi.

Either way, the findings show that it is indeed possible to make a vegan kimchi that's remarkably similar in terms of microbes to for kimchi that's made with more traditional ingredients. The jury is still out on whether consuming probiotics actually makes meaningful changes to the gut microbiome or has any overall health benefits, the researchers say. But to the extent that consumers want products with probiotics and producers want to cater to dietary restrictions, vegan kimchi appears to fit the bill.

Research appearing today in Nature Communications finds useful new information-handling potential in samples of tin(II) sulfide (SnS), a candidate "valleytronics" transistor material that might one day enable chipmakers to pack more computing power onto microchips. 

The research was led by Jie Yao of the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and Shuren Lin of UC Berkeley's Department of Materials Science and Engineering and included scientists from Singapore and China. Berkeley Lab's Molecular Foundry, a DOE Office of Science user facility, contributed to the work.

For several decades, improvements in conventional transistor materials have been sufficient to sustain Moore's Law - the historical pattern of microchip manufacturers packing more transistors (and thus more information storage and handling capacity) into a given volume of silicon. Today, however, chipmakers are concerned that they might soon reach the fundamental limits of conventional materials. If they can't continue to pack more transistors into smaller spaces, they worry that Moore's Law would break down, preventing future circuits from becoming smaller and more powerful than their predecessors.

That's why researchers worldwide are on the hunt for new materials that can compute in smaller spaces, primarily by taking advantage of the additional degrees of freedom that the materials offer - in other words, using a material's unique properties to compute more 0s and 1s in the same space. Spintronics, for example, is a concept for transistors that harnesses the up and down spins of electrons in materials as the on/off transistor states. 

Valleytronics, another emerging approach, utilizes the highly selective response of candidate crystalline materials under specific illumination conditions to denote their on/off states - that is, using the materials' band structures so that the information of 0s and 1s is stored in separate energy valleys of electrons, which are dependent on the crystal structures of the materials.

In this new study, the research team has shown that tin(II) sulfide (SnS) is able to absorb different polarizations of light and then selectively reemit light of different colors at different polarizations. This is useful for concurrently accessing both the usual electronic - and the material's valleytronic - degrees of freedom, which would substantially increase the computing power and data storage density of circuits made with the material.

"We show a new material with distinctive energy valleys that can be directly identified and separately controlled," said Yao. "This is important because it provides us a platform to understand how valley signatures are carried by electrons and how information can be easily stored and processed between the valleys, which are of both scientific and engineering significance."

Lin, the first author of the paper, said the material is different from previously investigated candidate valleytronics materials because it possesses such selectivity at room temperature without additional biases apart from the excitation light source, which alleviates the previously stringent requirements in controlling the valleys. Compared to its predecessor materials, SnS is also much easier to process.

With this finding, researchers will be able to develop operational valleytronic devices, which may one day be integrated into electronic circuits. The unique coupling between light and valleys in this new material may also pave the way toward future hybrid electronic/photonic chips.

Berkeley Lab's "Beyond Moore's Law" initiative leverages the basic science capabilities and unique user facilities of Berkeley Lab and UC Berkeley to evaluate promising candidates for next-generation electronics and computing technologies. Its objective is to build close partnerships with industry to accelerate the time it typically takes to move from the discovery of a technology to its scale-up and commercialization.

DES MOINES, IOWA - May 1, 2018 - Meat, such as pork, can be an important source of much-needed protein in an infant's diet during the transition to solid foods, according to new research from the University of Colorado published in the American Journal of Clinical Nutrition. (1) The first six to 12 months of life is a period of rapid growth when nutrition plays a pivotal role and, for many moms, meat may not be the first choice for an infant's complementary feeding. Yet this new research suggests a higher-protein diet, with meat as the primary source, may be beneficial for formula-fed infants when it comes to early length growth.

"Meat, such as pork, provides important micronutrients, is an excellent source of protein and can be an important complementary food for infants who are ready for solid foods," said lead study author Minghua Tang, Assistant Professor of Pediatrics at the University of Colorado. "Our research suggests introducing higher amounts of protein and introducing meat, such as pork, into the diet at five months could be potentially beneficial for linear growth (length gain)."

In the study, 64 healthy, formula-fed infants ate meat-based complementary foods, such as pureed ham and beef, or dairy-based complementary foods from ages five to 12 months old, increasing their protein intake from two grams of protein per kilogram each day before the study up to three grams per kilogram each day during the study period. While the protein increased, both calories and fat intakes stayed the same between the meat and dairy groups, regardless of protein source. Researchers found the pureed meats promoted a greater rate of growth - with length of nearly one inch greater compared to the dairy-fed group at 12 months of age, with no increase in risk of being overweight at the completion of the seven-month study. These findings build upon previous research demonstrating meat-based complementary foods promoted increases in length without excessive weight gain among breastfeed infants, too. (2)

The American Academy of Pediatrics recommends introducing solid foods at four to six months of age and advises exposing babies to a wide variety of healthy foods, including a variety of different textures. For babies who are mostly breastfeeding, meat may also have the added benefit of more easily absorbed iron and zinc, as breastfed infants are at a higher risk of becoming iron deficient than formula-fed infants. The World Health Organization also recognizes the need for protein early, recommending infants eat meat, poultry, fish or eggs daily, if possible. The U.S. Departments of Agriculture and Health and Human Services are also planning to expand the 2020-2025 Dietary Guidelines to include guidance on infant nutrition - given the pivotal role nutrition plays during infant growth.

While more research is needed to understand the potential long-term impacts of including meat, such as pork, in infant diets for growth, the benefits of pork in the diet overall are extensive. In addition to providing high-quality protein to promote growth and development, pork also provides iron and zinc - two key nutrients for which this age group may be deficient during periods of rapid growth.

"This research is particularly exciting because it shows nutrient-rich pork can play an important role in the whole family's diet," said Adria Huseth, registered dietitian and manager of nutrition communications and research at National Pork Board. "It's nutrient-rich, as well as a versatile, affordable and accessible protein."

(PHILADELPHIA) - Immunotherapy has given patients and oncologists new options, which for some patients, has meant cures for diseases that had been untreatable. Colorectal cancer has a high mortality rate in advanced stages of the disease with few effective therapies. Researchers at the Sidney Kimmel Cancer Center (SKCC) at Jefferson Health show that a type of immunotherapy called CAR-T cell therapy, successfully kills tumors and prevents metastases in mouse models of the disease. The work published in the journal Cancer Immunology Research, is the last step of preclinical testing prior to human clinical trials.

"The antigen we target for colorectal cancer is one that is shared across several high mortality cancers including esophageal and pancreatic cancer," said Adam Snook, PhD, Assistant Professor in the department of Pharmacology & Experimental Therapeutics at Jefferson (Philadelphia University + Thomas Jefferson University). "Taken together, 25 percent of people who die from cancer could potentially be treated with this therapy."

"Colorectal cancer rates are exceptionally high in our region, and advanced stage disease is difficult to treat. The concept of moving CAR-T cell therapy to colorectal cancer is a major breakthrough, and could address a major unmet clinical need. We are optimistic about the pre-clinical results," said Karen Knudsen, PhD, Director of the Sidney Kimmel Cancer Center at Jefferson Health, one of only 69 NCI-Designated Centers in the US.

CAR-T immunotherapy involves removing a patient's immune cells, engineering them to target the tumor (and only the tumor) and then multiplying those cells en masse before infusing them back into the patient. This powerful burst of targeted immune cells, quickly overcomes the cancer's own immune-suppression to kill the tumors, but requires a marker or homing beacon specific to the cancer. For colorectal cancer that beacon, or tumor antigen, is called GUCY2C. The antigen was identified as a potential biomarker and therapeutic target in colorectal cancer by Scott Waldman, MD, PhD, Chair of the Department of Pharmacology & Experimental Therapeutics at Jefferson, and a leader of the SKCC's Gastrointestinal Cancer program.

Dr. Snook created a CAR-T therapy made specifically to treat GUCY2C-expressing cancers such as colorectal cancer. In this study, the researchers tested a human-ready version of the therapy in mice.

They showed that mice with human colorectal tumors treated with CAR-T therapy successfully fought the tumor cells. All of the mice studied survived without side effects for the duration of the observation period - or 75 days, compared to a 30-day average survival of mice with control treatment.

In order to more closely replicate late-stage disease in humans, Dr. Snook and colleagues also looked at a mouse model of colorectal cancer that developed lung metastases, a common site for metastasis in colorectal cancer patients. Mice that were treated with the CAR-T therapy survived over 100 days with no metastases, whereas the control group survived an average of 20 days. Although the current experiments were not designed to test for autoimmunity-related side effects, earlier work by Dr. Snook and colleagues demonstrated no off-target effects. In that study, the researchers used a mouse-version of the CAR-T therapy that had the potential to react to off-target mouse organs, but saw no adverse effects.

"Safety is a major concern for the CAR-T therapy approach. In other cancers, the field has observed lethal autoimmune responses," said Dr. Snook. "Other researchers are developing fast-acting antidotes to CAR-T therapy to quell these safety concerns, but our data suggests that GUCY2C CAR-T therapy may be very effective and safe in cancer patients."

The next steps for the researchers would be a phase 1 clinical trial in humans.

DURHAM, N.C. -- Researchers at Duke University have built the first metal-free, dynamically tunable metamaterial for controlling electromagnetic waves. The approach could form the basis for technologies ranging from improved security scanners to new types of visual displays.

The results appear on April 9 in the journal Advanced Materials.

A metamaterial is an artificial material that manipulates waves like light and sound through properties of its structure rather than its chemistry. Researchers can design these materials to have rare or unnatural properties, like the ability to absorb specific ranges of the electromagnetic spectrum or to bend light backward.

"These materials are made up of a grid of separate units that can be individually tuned," said Willie Padilla, professor of electrical and computer engineering at Duke. "As a wave passes through the surface, the metamaterial can control the amplitude and phase at each location in the grid, which allows us to manipulate the wave in a lot of different ways."

In the new technology, each grid location contains a tiny silicon cylinder just 50 microns tall and 120 microns wide, with the cylinders spaced 170 microns apart from one another. While silicon is not normally a conductive material, the researchers bombard the cylinders with a specific frequency of light in a process called photodoping. This imbues the typically insulating material with metallic properties by exciting electrons on the cylinders' surfaces.

These newly freed electrons cause the cylinders to interact with electromagnetic waves passing through them. The size of the cylinders dictates what frequencies of light they can interact with, while the angle of the photodoping affects how they manipulate the electromagnetic waves. By purposefully engineering these details, the metamaterial can control electromagnetic waves in many different ways.

For this study, the cylinders were sized to interact with terahertz waves -- a band of the electromagnetic spectrum that sits between microwaves and infrared light. Controlling this wavelength of light could improve broadband communications between satellites or lead to security technology that can easily scan through clothing. The approach could also be adapted to other bands of the electromagnetic spectrum -- like infrared or visible light -- simply by scaling the size of the cylinders.

"We're demonstrating a new field where we can dynamically control each point of the metasurface by adjusting how they are being photodoped," Padilla said. "We can create any type of pattern we want to, allowing us to create lenses or beam-steering devices, for example. And because they're controlled by light beams, they can change very fast with very little power."

While existing metamaterials control electromagnetic waves through their electric properties, the new technology can also manipulate them through their magnetic properties.

"This allows each cylinder to not only influence the incoming wave, but the interaction between neighboring cylinders," said Kebin Fan, a research scientist in Padilla's laboratory and first author of the paper. "This gives the metamaterial much more versatility, such as the ability to control waves traveling across the surface of the metamaterial rather than through it."

"We're more interested in the basic demonstration of the physics behind this technology, but it does have a few salient features that make it attractive for devices," Padilla said.

"Because it is not made of metal, it won't melt, which can be a problem for some applications," he said. "It has subwavelength control, which gives you more freedom and versatility. It is also possible to reconfigure how the metamaterial affects incoming waves extremely quickly, which has our group planning to explore using it for dynamic holography."

Scientists have found immune cells can fight different strains of the same virus - a discovery which could help transform vaccine development.

Vaccines become ineffective when a virus mutates, and tackling this problem is a priority for researchers. Vaccinations aim to stimulate the body to produce "memory" cells which provide long-lasting protection from disease. Until now it was thought that these cells could only remember - and be able to protect against - one particular strain of virus.

Researchers have now found the immune system can produce memory cells which have the ability to recognise different strains of the same virus, rather than just one. This could help scientists transform the way vaccines are produced and given.

Diseases such as influenza, Dengue fever and AIDS are caused by viruses which constantly mutate, allowing them to hide from the immune system and evade any response from their host. Current vaccines can provide good protection against particular strains of virus but fail to protect against new strains caused by genetic mutation. For this reason the influenza vaccine, for example, has to be updated and administered annually, often with limited success, to pre-empt the appearance of new variant viruses.

Dr Harry White, from the University of Exeter, who led the Wellcome Trust-funded research, said: "Trying to find vaccines which can protect people against different strains of virus is a focus for scientists around the world. So far, despite a large global effort, there has been limited success in the war against virus mutation.

"We have found the immune system is able to recognise threats from new strains of a virus. We have long known of the existence of different types of immune memory cells, and now we know what these differences mean.

"After exposure to one strain of virus, these memory cells are then better able to recognise variants of the virus if they encounter them in the future. The immune system learns to protect against a whole group of related viruses, not just the one it experienced. It is this property that needs to be exploited to help make broadly protective vaccines."

The memory cells examined in this study are immature, or less developed, which allows them to more easily change and adapt to fight different viral strains. The antibodies from these cells are less focused on the infecting virus, but this is an advantage if the virus has mutated.

The research involved academics from the University of Exeter, University of Bristol and University of Birmingham testing the reaction of mice vaccinated with proteins from different strains of virus. Through painstakingly isolating hundreds of different individual cells and analysing the different antibodies each one made they were able to detect the presence of the immature cells that made these less focused antibodies. The mice which were immunised sequentially with proteins from different strains of the same virus produced more of these less developed memory cells.

Professor Rick Titball said "The holy grail for many scientists is to find a way of developing vaccines which work against all strains of a microorganism. This work could bring us a step closer to this and avoid, for example, the need to develop a new flu vaccine each year"

Variant proteins stimulate more IgM+ GC B-cells revealing a mechanism of cross-reactive recognition by antibody memory is published in the journal eLife.

Stanford researchers have developed a water-based battery that could provide a cheap way to store wind or solar energy generated when the sun is shining and wind is blowing so it can be fed back into the electric grid and be redistributed when demand is high.

The prototype manganese-hydrogen battery, reported today in Nature Energy, stands just three inches tall and generates a mere 20 milliwatt hours of electricity, which is on par with the energy levels of LED flashlights one might hang a key ring.

Despite the prototype's diminutive output, the researchers are confident they can take this table-top technology up to an industrial-grade system that could charge and recharge up to 10,000 times, creating a grid-scale battery with a useful lifespan well in excess of a decade.

Yi Cui, a professor of materials science at Stanford and senior author on the paper, said manganese-hydrogen battery technology could be one of the missing pieces in the nation's energy puzzle - a way to store unpredictable wind or solar energy so as to lessen the need to burn reliable but carbon-emitting fossil fuels when the renewable sources aren't available.

"What we've done is thrown a special salt into water, dropped in an electrode, and created a reversible chemical reaction that stores electrons in the form of hydrogen gas," Cui said.

Clever chemistry

The team that dreamed up the concept and built the prototype was led by Wei Chen, a postdoctoral scholar in Cui's lab. In essence the researchers coaxed a reversible electron-exchange between water and manganese sulfate, a cheap, abundant industrial salt used to make dry cell batteries, fertilizers, paper and other products.

To mimic how a wind or solar source might feed power into the battery, the researchers attached a power source to the prototype. The electrons flowing in reacted with the manganese sulfate dissolved in the water to leave particles of manganese dioxide clinging to the electrodes. Excess electrons bubbled off as hydrogen gas thus storing that energy for future use. Engineers know how to recreate electricity from the energy stored in hydrogen gas so the important next step was to prove was that the water-based battery can be recharged.

The researchers did this by re-attaching their power source to the depleted prototype, this time with the goal of inducing the manganese dioxide particles clinging to the electrode to combine with water, replenishing the manganese sulfate salt. Once this salt was restored, incoming electrons became surplus, and excess power could bubble off as hydrogen gas, in a process that can be repeated again and again and again.

Cui estimated that, given the water-based battery's expected lifespan, it would cost a penny to store enough electricity to power a 100 watt lightbulb for twelve hours.

"We believe this prototype technology will be able to meet Department of Energy (DOE) goals for utility-scale electrical storage practical," Cui said.

The DOE has recommended batteries for grid-scale storage should store and then discharge at least 20 kilowatts of power over a period of an hour, be capable of at least 5,000 recharges, and have a useful lifespan of 10 years or more. To make it practical such a battery system should cost $2,000 or less, or $100 per kilowatt hour.

Former Department of Energy Secretary and Nobel laureate Steven Chu, now a professor at Stanford, has a long-standing interest in encouraging technologies to help the nation transition to renewable energy.

"While the precise materials and design still need development, this prototype demonstrates the type of science and engineering that suggest new ways to achieve low-cost, long-lasting utility-scale batteries," said Chu, who was not a member of research team.

Shifting away from carbon

According to DOE estimates, about 70 percent of U.S. electricity is generated by coal or natural gas plants, which account for 40 percent of carbon dioxide emissions. Shifting to wind and solar generation is one way to reduce those emissions but it creates new challenge involving the variability of power supply. Most obviously, the sun only shines by day and, sometimes, the wind doesn't blow.

But another less-well understood but import form of variability come from surges of demand on the grid - that network of high-tension wires that distribute electricity over regions and ultimately to homes. On a hot day, when people come home from work and crank up the air conditioning, utilities must have load-balancing strategies to meet peak demand: some way to boost power generation within minutes to avoid brownouts or blackouts that might otherwise bring down the grid.

Today utilities often accomplish this by firing up on-demand or "dispatchable" power plants that may lay idle much of the day, but can come online within minutes - producing quick energy but boosting carbon emissions. Some utilities have developed short-term load balancing that does not rely on fossil-fuel burning plants. The most common and cost effect such strategy is pumped hydroelectric storage: using excess power to send water uphill, then letting it flow back down to generate energy during peak demand. However, hydroelectric storage only works in regions with the water and the space, so to make wind and solar more useful DOE has encouraged high capacity batteries as an alternative.

High capacity, low cost

Cui said there are several types of rechargeable battery technologies on the market, but it isn't clear which approaches will meet DOE requirements and prove their practicality to the utilities, regulators and other stakeholders who maintain the nation's electrical grid.

For instance, Cui said rechargeable lithium ion batteries, which store the small amounts of energy needed to run phones and laptops, are based on rare materials and are thus too pricey to store power for a neighborhood or city. Cui said grid-scale storage requires a low-cost, high-capacity, rechargeable battery and the manganese-hydrogen process seems promising.

"Other rechargeable battery technologies are easily more than 5 times of that cost over the life time," Cui added.

Chen said novel chemistry, low cost materials and relative simplicity made the manganese-hydrogen battery ideal for low-cost grid-scale deployment.

"The breakthrough we report in Nature Energy has the potential to meet DOE's grid-scale criteria," Chen said.

The prototype needs development work to prove itself. For one thing it uses platinum as a catalyst to spur the crucial chemical reactions at the electrode that make the recharge process efficient, and the cost of that component would be prohibitive for large-scale deployment. But Chen said the team is already working on cheaper ways to coax the manganese sulfate and water to perform the reversible electron exchange.

"We have identified catalysts that could bring us below the $100 per kilowatt hour DOE target," he said.

The researchers reported doing 10,000 recharges of the prototypes, which is twice the DOE requirements, but say it will be necessary to test the manganese-hydrogen battery under actual electric grid storage conditions in order to truly assess its lifetime performance and cost.

Cui said he has sought to patent process through the Stanford Office of Technology Licensing, and plans to form a company to commercialize the system.

Yi Cui is also a professor in the Photon Science Directorate at SLAC National Accelerator Laboratory, and a Senior Fellow of the Precourt Institute for Energy, a member of Stanford Bio-X and the Stanford Neurosciences Institute. Additional coauthors include Guodong Li, a visiting scholar in materials science and engineering and now with the Chinese Academy of Sciences; postdoctoral scholars Hongxia Wang, Jiayu Wan, Lei Liao, Guangxu Chen and Jiangyan Wang; visiting scholar Hao Zhang; and graduate students Zheng Liang, Yuzhang Li and Allen Pei.

This work was funded by the Department of Energy.

As an ASU graduate student, Rachel Yoho wanted to push the boundaries of renewable energy research. What she didn't fully anticipate is that it would also lead her to questioning how climate change is taught in today's universities.

In the Biodesign Center for Environmental Biotechnology, led by director and ASU Regents' Professor (and recent Stockholm Water Prize winner) Bruce Rittmann, she found a welcome home to make her research thrive.

There, she focused on microbes that were giving the renewable energy field a literal jolt. For her dissertation work, led under the guidance of mentor César Torres, she published several groundbreaking papers on advances in microbial fuel cells, which turn waste into electricity through a bacterial biofilm that has the ability to grow and thrive on an electrode.

"They breathe the metal, and give us electrons for energy in the process," said Yoho.

But while pursuing her Ph.D., she also became interested in the art of teaching science and earned a certificate in scientific teaching in higher education.

Among the most polarizing issues encountered in science and society today is the topic of global climate change. Despite nearly universal scientific consensus that it is indeed real and caused by us, the American public and politicians continue to be skeptical of the science.

She was inspired by her science education courses to ask research questions that reflected the interdisciplinary nature of her lab-based research in the Biodesign Swette Center for Environmental Biotechnology at ASU's Biodesign Institute. So, when she started examining the topic of climate change in introductory science courses by pouring over introductory science textbooks, Yoho was surprised by the paucity of materials devoted toward subjects like global warming, climate change and renewable energy applications.

"In a cutting-edge research lab, we are used to looking at things across disciplines," said Yoho, who now performs research and teaches at Miami University in Oxford, Ohio. "Within the educational environment, I wanted to see how different disciplines approach topics, and so, we looked at the terminology and content of textbooks, which are likely the most well-established and well-respected first or second stops for information in undergraduate education."

The introductory textbooks were also chosen because they "represent the intersection of teaching to non-scientists (popularization of science) and training for future scientists."

Now, in new research published in the journal Environmental Communication, Yoho and co-author Rittmann examined more than the 15,000 combined pages from current editions of 16 of the leading physics, biology and chemistry undergraduate textbooks published between 2013 and 2015.

They found that less than 4 percent of pages were devoted toward discussing climate change, global warming, related environmental issues or renewable energy applications.

In addition, the research team found:

While they observed a large variation for individual books, biology textbooks had on average the largest number of pages discussing the effects of climate change, but still less than 2 percent, while chemistry textbooks showed the largest variation, and physics books have an average of less than 0.5 percent of total pages;

The greatest content is in the final third of the book for biology and chemistry, which supports a general trend in education in that "applications" usually are addressed towards the end of a course of study, building on a firm foundation of content knowledge;

Among the three disciplines, the least emphasis was placed on renewable energy technologies in the biology textbooks examined. Characteristically, alternative fuels and other technologies related to the transportation sector are emphasized heavily in chemistry and physics;

Nuclear energy, which was addressed separately, is found on less than 1 percent of textbook pages and unfavorably represented.

"The terms we included were not just limited to a keyword search, but also involved going page by page through each of the textbooks. We looked for related topics like any applications and discoveries related to fossil fuels, and renewable energy technologies like wind and solar," said Yoho.

They noted that climate change, global warming, fossil fuels, renewable energy, and nuclear energy are not often a focus of the textbooks or course for these disciplines. Furthermore, these topics may not even be the focus of a single unit in one of these courses and are unlikely to be a primary factor in the selection of the course textbook.

However, these cross-cutting topics of socio-scientific debate represent important societal and environmental contexts for developing informed and productive citizens.

"The discussion within these traditional, compartmentalized science disciplines has implications on introductory-level science education, the public perception of science, and an informed citizenship," said Rittmann.

Going forward, they think perhaps it's time for introductory sciences to be more explicit about some of these pressing topics that span multiple disciplines.

"It's a difficult balance in an introductory course," said Yoho. "There's so much information to cover in a short time. However, our students are facing these issues inside and outside of the classrooms. Our communities feel the impacts of our energy decisions and climate." Some discussion can go a long way towards preparing students. "A next step might be to focus on the terms and content we discuss, as well as the potential role of these topics in introductory education," she added.

"However, no single discipline can tackle this alone," wrote Yoho in the paper. "While the traditional disciplinary lines influence specific discussions, the overall trends reveal a relatively small percentage of pages allotted to the topics related to energy technologies, climate change, and related environmental issues across the disciplines."

By documenting that large textbooks devote relatively few pages to these pressing societal issues, this research calls into question the effectiveness of the information provided to students in introductory materials.

The energy transition depends on technologies that allow the inexpensive temporary storage of electricity from renewable sources. A promising new candidate is aluminium batteries, which are made from cheap and abundant raw materials.

Scientists from ETH Zurich and Empa - led by Maksym Kovalenko, Professor of Functional Inorganic Materials - are among those involved in researching and developing batteries of this kind. The researchers have now identified two new materials that could bring about key advances in the development of aluminium batteries. The first is a corrosion-resistant material for the conductive parts of the battery; the second is a novel material for the battery's positive pole that can be adapted to a wide range of technical requirements.

Aggressive electrolyte fluid

As the electrolyte fluid in aluminium batteries is extremely aggressive and corrodes stainless steel, and even gold and platinum, scientists are searching for corrosion-resistant materials for the conductive parts of these batteries. Kovalenko and his colleagues have found what they are looking for in titanium nitride, a ceramic material that exhibits sufficiently high conductivity. "This compound is made up of the highly abundant elements titanium and nitrogen, and it's easy to manufacture," explains Kovalenko.

The scientists have successfully made aluminium batteries with conductive parts made of titanium nitride in the laboratory. The material can easily be produced in the form of thin films, also as a coating over other materials such as polymer foils. Kovalenko believes it would also be possible to manufacture the conductors from a conventional metal and coat them with titanium nitride, or even to print conductive titanium nitride tracks on to plastic. "The potential applications of titanium nitride are not limited to aluminium batteries. The material could also be used in other types of batteries; for example, in those based on magnesium or sodium, or in high-voltage lithium-ion batteries," says Kovalenko.

An alternative to graphite

The second new material can be used for the positive electrode (pole) of aluminium batteries. Whereas the negative electrode in these batteries is made of aluminium, the positive electrode is usually made of graphite. Now, Kovalenko and his team have found a new material that rivals graphite in terms of the amount of energy a battery is able to store. The material in question is polypyrene, a hydrocarbon with a chain-like (polymeric) molecular structure. In experiments, samples of the material - particularly those in which the molecular chains congregate in a disorderly manner - proved to be ideal. "A lot of space remains between the molecular chains. This allows the relatively large ions of the electrolyte fluid to penetrate and charge the electrode material easily," Kovalenko explains.

One of the advantages of electrodes containing polypyrene is that scientists are able to influence their properties, such as the porosity. The material can therefore be adapted perfectly to the specific application. "In contrast, the graphite used at present is a mineral. From a chemical engineering perspective, it cannot be modified," says Kovalenko.

As both titanium nitride and polypyrene are flexible materials, the researchers believe they are suitable for use in "pouch cells" (batteries enclosed in a flexible film).

Batteries for the energy transition

An increasing amount of electricity is generated from solar and wind energy. However, as electricity is needed even when the sun is not shining and the wind is not blowing, new technologies will be needed, such as new types of batteries, to store this electricity in a cost-effective manner. Although existing lithium-ion batteries are ideal for electromobility due to their low weight, they are also quite expensive and therefore unsuitable for economical large-scale, stationary power storage.

Furthermore, lithium is a relatively rare metal and is hard to extract - unlike aluminium, magnesium or sodium. Batteries based on one of the latter three elements are thus seen as a promising option for stationary power storage in the future. However, such batteries are still at the research stage and have not yet entered industrial use.

New research published in The Journal of Physiology has illuminated the effects of night-time light exposure on internal body clock processes. This is important for helping those who have poor quality sleep, such as shift workers, and could help improve treatments for depression.

The body has an internal clock that causes various physiological processes to oscillate in 24-h cycles, called circadian rhythms, which includes daily changes in sleepiness. Light is the strongest environmental time cue that resets the body's internal 24-h clock. Melatonin is a hormone produced in the brain at night that regulates this body clock and exposure to light before bedtime may reduce sleep quality by suppressing its production. The research team aimed to explore the link between the physiological process that enables our internal body clock to synchronise to external time cues (i.e. day and night) - called circadian phase resetting - and suppression of melatonin.

Melatonin suppression and circadian phase resetting are often correlated such that high levels of melatonin suppression can be associated with large shifts of the body clock. This association between the two responses has often been assumed to represent a functional relationship, resulting in the acceptance that one could be used as a proxy measure for the other. Circadian phase resetting is more difficult to measure than melatonin suppression, meaning the latter has often been used to assess disruption to the body clock caused by light exposure at night. However, this research has found that the magnitude of the shift in internal body clock is functionally independent from melatonin suppression. This casts doubt on the use of melatonin suppression as a proxy for circadian phase resetting. This knowledge may shape future research designed to improve treatments for depression and shift work sleep disorder.

The researchers tested the association between melatonin suppression and circadian phase resetting in participants who received either continuous or intermittent bright light exposure at night. This research procedure involved each participant completing a 9-10 day inpatient study at Brigham and Women's Hospital, Boston, under highly controlled laboratory conditions with strict control over their sleep/wake, activity and light/dark schedules. Intermittent exposure patterns were found to show significant phase shifts with disproportionately less melatonin suppression. Moreover, each and every intermittent bright light pulse induced a similar degree of melatonin suppression, but did not appear to cause an equal magnitude of phase shift.

Despite the results of this study suggesting functional independence in circadian phase resetting and melatonin suppression responses to exposure to light at night, the study's conclusions may be restricted by the limited sample size in each light exposure condition.

Lead author Dr Shadab Rahman is excited by his team's findings, and is looking forward to investigating new avenues of interest they have opened up:

"Overall, our data suggest that melatonin suppression and phase resetting are sometimes correlated, but ultimately are regulated by separate neurophysiological processes. Therefore melatonin suppression is not a reliable surrogate for phase resetting. This is an important consideration for developing light-therapy treatments for people who have poor quality sleep and biological clock disruption, such as shift workers, or disorders such as depression. Additional work is needed to optimize light therapy protocols used as treatment."

A study by researchers from the National University of Singapore (NUS) and the University of Sao Paulo revealed that a beltway constructed to divert heavy-duty diesel vehicles traffic in the Brazilian city of Sao Paulo has reduced public health damage associated with exposure to diesel. The positive health outcomes of the intervention could guide the formulation of similar transport polices in other cities, where humans and diesel vehicles reside and transit in close proximity.

In densely populated cities like Sao Paulo, many vehicles running on diesel such as commercial trucks, vans and buses circulate right by where people live, causing them to be constantly exposed to high levels of diesel emission. It is critical to manage diesel emission in these cities as diesel emits highly pollutive particulate matter and nitrogen oxides that increase the risk of respiratory and cardiovascular diseases, among other illnesses.

Health outcomes of Sao Paulo's beltway

In 2010, Sao Paulo constructed a beltway along sparsely populated areas that are 25 kilometres away from the city centre. The original intent of building the beltway was to enable heavy-duty vehicles to bypass the densely populated neighbourhoods, and thereby ease traffic congestion in the inner-city roads.

While the intervention did immediately relieve road congestion by 20 per cent, the NUS researchers found that the effect was short-lived as passenger cars quickly replaced the inner-city road space which the heavy-duty vehicles had left behind. However, the researchers also found that the replacement of heavy-duty diesel vehicles with gasoline-ethanol passenger cars on the inner-city roads resulted in a sustained drop in the level of nitrogen oxides in the air, reducing air pollution in the city even after the traffic congestion rebounded.

The improved air quality in Sao Paulo also translated into long-lasting positive health outcomes for its residents. The researchers observed that the compositional change in traffic in the inner-city roads resulting from the beltway's diversion of diesel vehicles led to an overall estimated reduction of 5,000 hospital admissions associated with respiratory and cardiovascular illness every year. The researchers quantify about one annual premature death for every 100-200 diesel trucks using inner-city roads.

A lesson for cities around the world

"The unintentional improvement in air quality and public health resulting from the Sao Paulo beltway demonstrates how judicious transport policies can benefit public health. Other world megacities such as London, Paris, New Delhi and Singapore may stand to gain similarly by limiting the circulation of diesel vehicles in the cities, particularly during the day when people are out and about" said Associate Professor Alberto Salvo from the Department of Economics at NUS Faculty of Arts and Social Sciences who led the study.

Like Sao Paulo, many major cities in the world have large volumes of diesel trucks, buses and vans transiting in close proximity with people, resulting in similar levels of air pollution. For example, nearly 40 per cent of London's total nitrogen oxides emissions is attributed to diesel vehicles. Relative to North America, Europe's households have significantly adopted diesel cars over gasoline and alternative fuels.

Different cities may adopt different abatement strategies, such as the Ultra-Low Emission Zone charge in London and the temporary ban on diesel cars in Oslo, and thus it is crucial that policymakers evaluate a range of policies in order to select a combination of strategies most effective for their cities.

Sao Paulo's beltway construction provides a rare intervention, at the scale of a real-world metropolis, of the air and health benefits from shifting the urban transportation fuel mix away from diesel. Policymakers in other cities where human exposure to diesel runs high may learn from Sao Paulo's experience.

The study "External Effects of Diesel Trucks Circulating Inside the Sao Paulo Megacity" was published in the Journal of the European Economic Association on 27 April 2018. The paper was co-authored by Dr He Jiaxiu, Post-doctoral Fellow from the Department of Economics at NUS Faculty of Arts and Social Sciences and Professor Nelson Gouveia from the Faculty of Medicine at the University of Sao Paulo.

April 27, 2018 - Hearing is an important part of fitness-for-duty assessments of police officers and other public safety professionals - but standard hearing tests don't give a true picture of whether these professionals can hear and communicate in the specific "noise environments" where they must work. A new approach to hearing assessment in public safety officers -- which has been adopted by five government agencies in the United States and Canada -- is presented in an article in Ear and Hearing. The official journal of the American Auditory Society, Ear and Hearing is published by Wolters Kluwer.

An international group led by Dr. Sigfrid D. Soli, PhD, of the House Clinic, Los Angeles, has developed and validated a new method for assessing auditory fitness for duty for public safety occupations - focusing on whether these professionals can perform "hearing-critical" job tasks in the settings where they must work. "This method is the first to provide an objective, evidence-based means assessing functional hearing in individuals who must perform hearing-critical job tasks that can directly affect public safety," Dr. Soli commented.

New Model for Occupational Hearing Screening Accounts for 'Real-World Noise Environments'

Dr. Soli and colleagues have taken a new approach to assessing fitness for duty in public safety professionals with hearing loss. Current guidelines for hearing screening use standard diagnostic tests of hearing disorders, such as pure-tone audiometry. However, these tests do not necessarily provide objective information as to whether the individual can effectively perform essential hearing-critical job tasks in everyday occupational settings.

With standard diagnostic hearing tests, some individuals with hearing loss can be denied access to public safety positions or removed from their jobs - even with hearing technologies that may allow them to function adequately. Current approaches also may not be valid under the Americans with Disabilities Act, which requires that screening criteria reflect the actual requirements of the job.

To develop their model, Dr. Soli and colleagues conducted research to evaluate hearing-critical tasks and real-world noise environments in public safety and law enforcement jobs: specifically, law enforcement and corrections officers. Their studies included expert analyses of the essential hearing-critical tasks for each type of job, along with on-site recordings of the noise environments where those tasks are performed.

The studies included many noise environments for law enforcement and corrections officers. For example, for police officers, effective in-person and radio communications often take place in a background of indoor and outdoor voices, vehicle sounds, sirens, and other noises. The researchers used the Extended Speech Intelligibility Index, which is based on an American National Standard, to obtain measures of functional hearing ability necessary for effective speech communication in each noise environment.

The researchers found that even for individuals with normal hearing, real-world noise environments pose a challenge to effective communication. In noisy environments, the likelihood of effective speech communication at distances of one meter or less was often predicted to be less than 50 percent. With raised or loud vocal effort, predicted likelihood values increased to 80 percent or higher. At distances of five meters or beyond, effective speech communication was often unlikely, regardless of vocal effort.

Based on their findings, Dr. Soli and colleagues developed a method for predicting the likelihood of effective speech communication in each real-world noise environment. In a companion article, published in the International Journal of Audiology, they validated these predictions in samples of adults with normal hearing and those with mild to moderate hearing impairment. They stated that "these predictions provide an objective means of occupational hearing screening" that more accurately reflects the way functional hearing ability influences job performance.

HOUSTON - (April 26, 2018) - Doctors could be a step closer to finding the most effective way to treat cancer with a double whammy of a virus combined with boosting the natural immune system, according to a pioneering study by researchers at The University of Texas Health Science Center at Houston (UTHealth) and The Ohio State University.

"The findings of this research are very exciting because it helps unravel the complex yin and yang relationship between the natural cancer-fighting power intrinsic to our immune system and externally added cancer-killing cells that are given as a therapy. It's very significant because it shows, contrary to recent scientific claims, that virotherapy can be combined with cell therapy for a positive effect," said the study's corresponding author Balveen Kaur, Ph.D., professor and vice chair of research in the Vivian L. Smith Department of Neurosurgery at McGovern Medical School at UTHealth.

Previous scientific wisdom has discredited combining virotherapy and externally added NK cell therapy to the body's natural killer (NK) cells, but there could be clear cancer-fighting benefits - providing enough external NK cells are deployed to destroy the tumor and stop its spread, as revealed in the paper published this week in Proceedings of the National Academy of Sciences of the United States of America (PNAS).

To reach this conclusion, physicians devised a mathematical formula unlocking the complex interactive relationship between externally introduced viruses and NK cells in addition to the immune system's existing NK cells to calculate cancer cell-killing potency. The mathematical modeling was able to predict how a virus-treated tumor would respond to NK cell therapy, depending on the number of NK cells introduced to the tumor. It showed that when the number of externally introduced NK cells is increased, the ability to fight cancer is strengthened. While the patient's own NK cells, present in smaller numbers, concentrate on clearing the virus and therefore have an adverse effect on virotherapy by limiting the virus's cancer-busting power, this impact can be reversed to destroy more of the tumor by introducing greater numbers of external NK cells. The theory behind these equations was subsequently confirmed in practice by experiments on mice with brain tumors, paving the way for further work.

NK cells are an essential part of the innate immune system and they play a critical role in protecting the body from cancer. The primary function of NK cells is to fight infections, which means they attack the introduced virus, thus thwarting its therapeutic capacity. However, if sufficient numbers of extra NK cells are added, they can kill more tumor cells directly and compensate for this negative influence.

"Natural NK cells sense and kill infected cancer cells, thus clearing viruses. But by adding exogenous NK cells in sufficient quantities, they can also destroy the residual tumor. Our tests showed when you get this ratio right, there's a significant improvement in cancer-fighting efficacy," said Kaur, who is a member of The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences. "So it's a big step forward, which should create more opportunities for further research and development of clinical trials for the treatment of cancer in humans and animals."