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EVANSTON, Ill. -- An international team of astronomers has captured the first-ever polarized radio waves from a distant cosmic explosion.

This explosive event (known as gamma-ray burst GRB 190114C) is part of a class of the most energetic explosions in the universe. It was produced when a star -- much more massive than our sun -- collapsed to form a black hole.

Gamma ray bursts produce powerful jets that travel close to the speed of light and shine with the incredible luminosity of more than a billion suns combined. Astronomers have struggled to understand how these jets are formed and why they seem to appear only in gamma ray bursts -- but not other explosions, such as ordinary supernovae.

Because these jets are extremely bright at radio wavelengths, the discovery of polarized radio signals may offer new clues to help solve this mystery. Polarization is a property of light that indicates how a magnetic field is organized and structured in a jet.

"We know that only a very tiny fraction (less than 1%) of massive stars form jets when they collapse," said Northwestern University's Raffaella Margutti, who contributed to the study. "But we have not known how they manage to launch these outflows with such extreme properties, and we don't know why only a few stars do this."

"This measurement opens a new window into gamma-ray burst science and the studies of energetic astrophysical jets," said Tanmoy Laskar, a postdoctoral researcher at the University of Bath in the U.K. and lead author of the study. "We would like to understand whether the low level of polarization measured in this event is characteristic of all gamma-ray bursts and, if so, what this could tell us about the magnetic structures in gamma-ray burst jets and the role of magnetic fields in powering jets throughout the universe."

The paper was published last week in the Astrophysical Journal Letters.

The international team included three astrophysicists from Northwestern's Weinberg College of Arts and Sciences: Kate Alexander, Wen-fai Fong and Margutti. All are members of Northwestern's Center for Interdisciplinary and Exploratory Research in Astrophysics (CIERA).

Astronomers have hypothesized that cosmic magnetic fields might flow through the jets, helping them form and providing structural support. The physical extent of these magnetic fields, which have implications for the jet launching mechanism, however, had never before been measured.

To obtain these measurements, the international team employed a novel trick. They observed the jets in linearly polarized light, which is sensitive to the size of magnetic field patches. Larger magnetic field patches, for example, produce more polarized light.

On January 14, 2019, a flash of gamma rays triggered NASA's Swift satellite, which alerted astronomers of the burst's location in the direction of the constellation Fornax. The astronomers then used the Atacama Large Millimeter/Submillimeter Array (ALMA) telescope in Chile to search for radio waves from the explosion, which occurred more than 4.5 billion years ago in a galaxy 7 billion light-years away.

"Magnetic fields are ubiquitous but notoriously difficult to constrain in our universe," said Fong, an assistant professor of astrophysics. "The fact that we have been able to detect their presence -- let alone in the fastest jets we know of -- is an incredible and storied feat of observation."

The team detected a subtle, but revealing, polarization signal of 0.8%, implying magnetic field patches about the size of our solar system. Next, the researchers will combine this new information with data from X-ray and visible light telescopes.

"The lower frequency data from the Very Large Array (VLA) in New Mexico helped confirm that we were seeing the light from the jet itself rather than from the interaction of the jet with its environment," said Alexander, a NASA Einstein Fellow who led the VLA observations.

"This is a truly remarkable measurement," said Margutti, "both from the technical side and for its deep scientific implications on the nature of magnetic fields in the most relativistic sources known in our universe."

Boston - Researchers at Boston Medical Center initiated a statewide quality improvement initiative to increase mothers' ability to produce and provide milk for very low birth weight infants at their discharge, as well reduce the racial/ethnic disparities in milk production and provision to these infants. A new study, published June 18th in Pediatrics, indicates that the initiative yielded positive results on improving rates of prenatal human milk education, early milk expression and skin to skin care among mothers of very low birth weight infants during initial hospitalization, but did not lead to sustained improvement in mother's milk provision at hospital discharge.

Mother's milk has many benefits for very low-birth-rate infants, including a reduction of necrotizing enterocolitis (infection of the intestine), sepsis, and chronic lung disease, and improvement in later childhood development. However, mothers of very low birth rate infants that are born prematurely often have challenges making milk. In addition, previous research has shown racial/ethnic disparities in mother's milk provision at discharge or transfer, with white mothers having a higher rate of mother's milk provision.

The researchers examined three years of data from 1,670 mother-very low birth weight infant pairs from 10 level 3 neonatal intensive care units in Massachusetts. They found that the quality improvement program significantly improved hospital-based breastfeeding support practices, as well as first milk expression within six hours of birth, and any skin-to-skin care in the first month in all racial/ethnic groups. Although the researchers found no racial/ethnic disparities in provision of mother's milk for the first three weeks of hospitalization, disparities emerged after three weeks.

"Although we were able to show improvement in our process measures and any mother's milk for the first three weeks of hospitalization, these did not lead to sustained improvement in mother's milk provision at discharge," said corresponding author Margaret G. Parker, MD, MPH, a neonatologist at Boston Medical Center and assistant professor of pediatrics at BU School of Medicine. "While we did not find improvements in our main outcome, we did find several successful initiatives that can inform other hospitals looking to address this issue."

The authors note that, given these results, further research is needed on the effect of factors later in hospitalization on provision of mother's milk at discharge. This work was supported by the W.K. Kellogg Foundation.

PITTSBURGH (June 19, 2019) ¬--Technologies like solar panels and LEDs require a cover material that repels water, dirt and oil while still letting plenty of light through. There is also interest in new flexible materials so these devices can be incorporated into a variety of creative applications like curtains, clothes, and paper. Researchers from the University of Pittsburgh's Swanson School of Engineering have created a flexible optical plastic that has all of those properties, finding inspiration in a surprising place: the shape of Enoki mushrooms.

The research, "Stain-Resistant, Superomniphobic Flexible Optical Plastics Based on Nano-Enoki Mushrooms," was published in the Journal of Materials Chemistry A (doi:10.1039/C9TA01753D).

The researchers created a plastic sheet surface with tall, thin nanostructures that have larger tops, like an Enoki mushroom. Named nano-enoki polyethylene terephthalate (PET), the nano-structures in the coating make the plastic sheet superomniphobic, repelling a wide range of liquids, while maintaining a high transparency. The surface can repel a variety of liquids such as not only water, but milk, ketchup, coffee, and olive oil. It also has high transparency and high haze, meaning it allows more light through, but that light is scattered. That makes it ideal for integrating with solar cells or LEDs, and combined with its flexible and durability, means it could be used in flexible lighting or wearable technology.

"The key thing with these structures is the shape - it keeps liquid on top of the nanostructure. This is the best in the literature so far in terms of high transparency, high haze and high oil contact angle," explains Sajad Haghanifar, lead author of the paper and doctoral candidate in industrial engineering at Pitt. "We show that substances that usually stain and leave residue behind, like mustard and blood, fall completely off the surface, even after they've dried." Videos show how the dried mustard and blood flake off the surface when the surface is tilted.

"The lotus leaf is nature's gold standard in terms of a liquid-repellant and self-cleaning surface," says Paul Leu, PhD, associate professor of industrial engineering, whose lab conducted the research. Dr. Leu holds secondary appointments in mechanical engineering and materials science and chemical engineering. "We compared our nano-enoki PET with a lotus leaf and found that ours was better at repelling more kinds of liquids, including olive oil, blood, coffee, and ethylene glycol. The surfaces not only resist staining from various liquids, but may be adapted for medical applications to resist bacteria or blood clotting."

The quest to discover what drove one of the most important evolutionary events in the history of life on Earth has taken a new, fascinating twist.

A team of scientists have given a fresh insight into what may have driven the "Cambrian Explosion" - a period of rapid expansion of different forms of animal life that occurred over 500 million years ago.

While a number of theories have been put forward to explain this landmark period, the most credible is that it was fuelled by a significant rise in oxygen levels which allowed a wide variety of animals to thrive.

The new study suggests that such a rise in oxygen levels was the result of extraordinary changes in global plate tectonics.

During the formation of the supercontinent 'Gondwana', there was a major increase in continental arc volcanism - chains of volcanoes often thousands of miles long formed where continental and oceanic tectonic plates collided. This in turn led to increased 'degassing' of CO2 from ancient, subducted sedimentary rocks.

This, the team calculated, led to an increase in atmospheric CO2 and warming of the planet, which in turn amplified the weathering of continental rocks, which supplied the nutrient phosphorus to the ocean to drive photosynthesis and oxygen production.

The study was led by Josh Williams, who began the research as an MSc student at the University of Exeter and is now studying for a PhD at the University of Edinburgh.

During his MSc project he used a sophisticated biogeochemical model to make the first quantification of changes in atmospheric oxygen levels just prior to this explosion of life.

Co-author and project supervisor Professor Tim Lenton, from the University of Exeter's Global Systems Institute said: "One of the great dilemmas originally recognised by Darwin is why complex life, in the form of fossil animals, appeared so abruptly in what is now known as the Cambrian explosion.

"Many studies have suggested this was linked to a rise in oxygen levels - but without a clear cause for such a rise, or any attempt to quantify it."

Not only did the model predict a marked rise in oxygen levels due to changes in plate tectonic activity, but that rise in oxygen - to about a quarter of the level in today's atmosphere - crossed the critical levels estimated to be needed by the animals seen in the Cambrian explosion.

Williams added: "What is particularly compelling about this research is that not only does the model predict a rise in oxygen to levels estimated to be necessary to support the large, mobile, predatory animal life of the Cambrian, but the model predictions also show strong agreement with existing geochemical evidence."

"It is remarkable to think that our oldest animal ancestors - and therefore all of us - may owe our existence, in part, to an unusual episode of plate tectonics over half a billion years ago" said Professor Lenton.

Considering the ever-growing percentage of bacteria that are resistant to antibiotics, interest in medical use of plasma is increasing. In collaboration with colleagues from Kiel, researchers at Ruhr-Universität Bochum (RUB) investigated if bacteria may become impervious to plasmas, too. They identified 87 genes of the bacterium Escherichia coli, which potentially protect against effective components of plasma. "These genes provide insights into the antibacterial mechanisms of plasmas," says Marco Krewing. He is the lead author of two articles that were published in the Journal of the Royal Society Interface this year.

A cocktail of harmful components stresses pathogens

Plasmas are created from gas that is pumped with energy. Today, plasmas are already used against multi-resistant pathogens in clinical applications, for example to treat chronic wounds. "Plasmas provide a complex cocktail of components, many of which act as disinfectants in their own right," explains Professor Julia Bandow, Head of the RUB research group Applied Microbiology. UV radiation, electric fields, atomic oxygen, superoxide, nitric oxides, ozone, and excited oxygen or nitrogen affect the pathogens simultaneously, generating considerable stress. Typically, the pathogens survive merely several seconds or minutes.

In order to find out if bacteria, may develop resistance against the effects of plasmas, like they do against antibiotics, the researchers analysed the entire genome of the model bacterium Escherichia coli, short E. coli, to identify existing protective mechanisms. "Resistance means that a genetic change causes organisms to be better adapted to certain environmental conditions. Such a trait can be passed on from one generation to the next," explains Julia Bandow.

Mutants missing single genes

For their study, the researchers made use of so-called knockout strains of E. coli. These are bacteria that are missing one specific gene in their genome, which contains approximately 4,000 genes. The researchers exposed each mutant to the plasma and monitored if the cells kept proliferating following the exposure.

"We demonstrated that 87 of the knockout strains were more sensitive to plasma treatment than the wild type that has a complete genome," says Marco Krewing. Subsequently, the researchers analysed the genes missing in these 87 strains and determined that most of those genes protected bacteria against the effects of hydrogen peroxide, superoxide, and/or nitric oxide. "This means that these plasma components are particularly effective against bacteria," elaborates Julia Bandow. However, it also means that genetic changes that result in an increase in the number or activity of the respective gene products are more capable of protecting bacteria from the effects of plasma treatment.

Heat shock protein boosts plasma resistance

The research team, in collaboration with a group headed by Professor Ursula Jakob from the University of Michigan in Ann Arbor (USA), demonstrated that this is indeed the case: the heat shock protein Hsp33, encoded by the hslO gene, protects E. coli proteins from aggregation when exposed to oxidative stress. "During plasma treatment, this protein is activated and protects the other E. coli proteins - and consequently the bacterial cell," Bandow points out. An increased volume of this protein alone results in a slightly increased plasma resistance. Considerably stronger plasma resistance can be expected when the levels of several protective proteins are increased simultaneously.

Artificial muscles made from polymers can now be powered by energy from glucose and oxygen, just like biological muscles. This advance may be a step on the way to implantable artificial muscles or autonomous microrobots powered by biomolecules in their surroundings. Researchers at Linköping University, Sweden, have presented their results in the journal Advanced Materials.

The motion of our muscles is powered by energy that is released when glucose and oxygen take part in biochemical reactions. In a similar way, manufactured actuators can convert energy to motion, but the energy in this case comes from other sources, such as electricity. Scientists at Linköping University, Sweden, wanted to develop artificial muscles that act more like biological muscles. They have now demonstrated the principle using artificial muscles powered by the same glucose and oxygen as our bodies use.

The researchers have used an electroactive polymer, polypyrrole, which changes volume when an electrical current is passed. The artificial muscle, known as a "polymer actuator", consists of three layers: a thin membrane layer between two layers of electroactive polymer. This design has been used in the field for many years. It works by the material on one side of the membrane acquiring a positive electrical charge and ions being expelled, causing it to shrink. At the same time, the material on the other side acquires a negative electrical charge and ions are inserted, which causes the material to expand. The changes in volume cause the actuator to bend in one direction, in the same way that a muscle contracts.

The electrons that cause motion in artificial muscles normally come from an external source, such as a battery. But batteries suffer from several obvious drawbacks: they are usually heavy, and need to be charged regularly. The scientists behind the study decided instead to use the technology behind bioelectrodes, which can convert chemical energy into electrical energy with the aid of enzymes. They have used naturally occurring enzymes, integrating them into the polymer.

"These enzymes convert glucose and oxygen, in the same way as in the body, to produce the electrons required to power motion in an artificial muscle made from an electroactive polymer. No source of voltage is required: it's enough simply to immerse the actuator into a solution of glucose in water", says Edwin Jager, senior lecturer in Sensor and Actuator Systems, in the Department of Physics, Chemistry and Biology at Linköping University. Together with Anthony Turner, professor emeritus, he has led the study.

Just as in biological muscles, the glucose is directly converted to motion in the artificial muscles.

"When we had fully integrated enzymes on both sides of the actuator and it actually moved - well, it was just amazing", says Jose Martinez, a member of the research group.

The next step for the researchers will be to control the biochemical reactions in the enzymes, such that the motion can be reversible for many cycles. They have already demonstrated that the motion is reversible, but they had to use a small trick to do so. Now they want to create a system that is even closer to a biological muscle. The researchers also want to test the concept using other actuators as the "textile muscle", and apply it in microrobotics.

"Glucose is available in all organs of the body, and it's a useful substance to start with. But it is possible to switch to other enzymes, which would enable the actuator to be used in, for example, autonomous microrobots for environmental monitoring in lakes. The advances we present here make it possible to power actuators with energy from substances in their natural surroundings", says Edwin Jager.

Researchers have examined what childhood behavior can tell us about how individuals will do economically later in life. But the methods they used to reach an answer were limited, which tempered the studies' findings. New longitudinal research that addressed these limitations examined the association between six prevalent childhood behaviors in kindergarten and annual earnings at ages 33 to 35 years. The study found that individuals who were inattentive at age 6 had lower earnings in their 30s after taking into consideration their IQ and family adversity. For males only, individuals who were physically aggressive or oppositional (e.g., who refused to share materials or blamed others) had lower annual earnings in their 30s. And males who were prosocial (e.g., who shared or helped) had higher later earnings.

The study, in the journal JAMA Psychiatry, was conducted by researchers at Carnegie Mellon University, the University of Montreal, University College Dublin, Observatoire Franc?ais des Conjonctures Economiques, Centre pour la Recherche Economique et Ses Applications, Statistics Canada, and Universite? de Bordeaux.

"Our study suggests that kindergarten teachers can identify behaviors associated with lower earnings three decades later," says Daniel Nagin, professor of public policy and statistics at Carnegie Mellon University's Heinz College, who coauthored the study. "Early monitoring and support for children who exhibit high levels of inattention, and for boys who exhibit high levels of aggression and opposition and low levels of prosocial behavior could have long-term socioeconomic advantages for those individuals and society."

The study used data from the Quebec Longitudinal Study of Kindergarten Children, a population-based sample of predominantly White boys and girls born in 1980 or 1981 in Quebec, Canada, who were followed from January 1, 1985, to December 31, 2015. In sum, 2,850 children were assessed. The data included behavioral ratings by kindergarten teachers when the children were 5 or 6 years old, as well as 2013 to 2015 government tax returns when the participants were 33 to 35 years old.

The study sought to test the associations between inattention (e.g., lacking concentration, being easily distracted), hyperactivity (e.g., feeling fidgety, moving constantly), physical aggression (e.g., fighting, bullying, kicking), opposition (e.g., disobeying, blaming others, being irritable), anxiety (e.g., worrying about many things, crying easily), and prosociality (e.g., helping someone who has been hurt, showing sympathy) when the children were in kindergarten and later reported annual earnings.

The study addressed limitations of prior research by assessing children earlier, including specific behaviors within a single model, so the results could be incorporated more easily into targeted intervention programs, and relied on reports from teachers instead of self-reports by children and tax records of income instead of adults' self-reported earnings.

Researchers found that boys and girls who were inattentive in kindergarten had lower earnings in their 30s. They also found that boys who were aggressive or oppositional at age 6 had lower earnings, and that boys who were prosocial at age 6 had higher earnings in their 30s.

"Early behaviors are modifiable, arguably more so than traditional factors associated with earnings, such as IQ and socioeconomic status, making them key targets for early intervention," explains Sylvana M. Côté, associate professor of social and preventative medicine at the University of Montreal, who coauthored the study. "If early behavioral problems are associated with lower earnings, addressing these behaviors is essential to helping children--through screenings and the development of intervention programs--as early as possible."

The study's authors acknowledge that they did not account for earnings through the informal economy or for unaccounted accumulation of debt. They also note that because they looked at associations, the study did not reach conclusions about causality.

Just beyond where conventional scuba divers can go is an area of the ocean that still is largely unexplored. In waters this deep -- about 100 to at least 500 feet below the surface -- little to no light breaks through.

Researchers must rely on submersible watercraft or sophisticated diving equipment to be able to study ocean life at these depths, known as the mesophotic zone. These deep areas span the world's oceans and are home to extensive coral reef communities, though little is known about them because it is so hard to get there.

A collaborative research team from the University of Washington, College of Charleston, University of California Berkeley, University of Hawaii and other institutions has explored the largest known coral reef in the mesophotic zone, located in the Hawaiian Archipelago, through a series of submersible dives. There, they documented life along the coral reef, finding a surprising amount of coral living in areas where light levels are less than 1% of the light available at the surface.

Their findings were published April 8 in the journal Limnology and Oceanography.

"Because mesophotic corals live close to the limits of what is possible, understanding their physiology will give us clues of the extraordinary strategies corals use to adapt to low-light environments," said lead author Jacqueline Padilla-Gamiño, an assistant professor in the UW School of Aquatic and Fishery Sciences.

Knowing how these deep coral reefs function is important because they appear to be hotspots for biodiversity, and home to many species found only in those locations, Padilla-Gamiño explained. Additionally, close to half of all corals in the ocean have died in the past 30 years, mostly due to warm water temperatures that stress their bodies, causing them to bleach and eventually die. This has been documented mostly in shallower reefs where more research has occurred. Scientists say that more information about deeper reefs in the mesophotic zone is critical for preserving that habitat.

"Mesophotic reefs in Hawaii are stunning in their sheer size and abundance," said co-author Heather Spalding at College of Charleston. "Although mesophotic environments are not easily seen, they are still potentially impacted by underwater development, such as cabling and anchoring, and need to be protected for future generations. We are on the tip of the iceberg in terms of understanding what makes these astounding reefs tick."

Padilla-Gamiño was on board during two of the team's eight submersible dives off the coast of Maui that took place from 2010 to 2011. Each dive was a harrowing adventure: Researchers spent up to eight hours in cramped quarters in the submersible that was tossed from the back of a larger boat, then disconnected once the submersible reached the water.

Once in the mesophotic zone, they collected specimens using a robot arm, and captured video footage and photos of life that has rarely been seen by humans.

"It's a really unbelievable place," Padilla-Gamiño said. "What is surprising is that, in theory, these corals should not be there because there's so little light. Now we're finally understanding how they function to be able to live there."

By collecting coral samples and analyzing their physiology, the researchers found that different corals in the mesophotic zone use different strategies to deal with low amounts of light. For example, some species of corals change the amount of pigments at deeper depths, while other species change the type and size of symbionts, which are microscopic seaweeds living inside the tissue of corals, Padilla-Gamiño explained. These changes allow corals to acquire and maximize the light available to perform photosynthesis and obtain energy.

Additionally, the corals at deeper depths are likely eating other organisms like zooplankton to increase their energy intake and survive under very low light levels. They probably do this by filter feeding, Padilla-Gamiño said, but more research is needed to know for sure.

The researchers hope to collect more live coral samples from the mesophotic zone to be able to study in the lab how the symbionts, and the corals they live inside, function.

"The more we can study this, the more information we can have about how life works. This is a remarkable system with enormous potential for discovery," Padilla-Gamiño said. "Our studies provide the foundation to explore physiological ?exibility, identify novel mechanisms to acquire light and challenge current paradigms on the limitations of photosynthetic organisms like corals living in deeper water."

Non-precious metal nanoparticles could one day replace expensive catalysts for hydrogen production. However, it is often difficult to determine what reaction rates they can achieve, especially when it comes to oxide particles. This is because the particles must be attached to the electrode using a binder and conductive additives, which distort the results. With the aid of electrochemical analyses of individual particles, researchers have now succeeded in determining the activity and substance conversion of nanocatalysts made from cobalt iron oxide - without any binders. The team led by Professor Kristina Tschulik from Ruhr-Universität Bochum reports together with colleagues from the University of Duisburg-Essen and from Dresden in the Journal of the American Chemical Society, published online on 30 May 2019.

"The development of non-precious metal catalysts plays a decisive role in realising the energy transition as only they are cheap and available in sufficient quantities to produce the required amounts of renewable fuels," says Kristina Tschulik, a member of the Cluster of Excellence Ruhr Explores Solvation (Resolv). Hydrogen, a promising energy source, can thus be acquired by splitting water into hydrogen and oxygen. The limiting factor here has so far been the partial reaction in which oxygen is produced.

Better than reaction rates currently achieved in industry

How efficiently cobalt iron oxide particles are able to catalyse oxygen generation was investigated by the researchers in the current work. They analysed many individual particles one after the other. The chemists allowed a particle to catalyse oxygen generation on the surface of the electrode and measured the current flow from this, which provides information about the reaction rate. "We have measured current densities of several kiloamps per square metre," says Tschulik. "This is above the reaction rates currently possible in industry."

The team showed that, for particles smaller than ten nanometres, the current flow is dependent on the particle size - the smaller the catalyst particle, the smaller the current. The current is also limited by the oxygen that is produced in the reaction and that diffuses away from the particle surface.

Extremely stable despite high stress

Following the catalysis experiments, the chemists observed the catalyst particles under the transmission electron microscope. "Despite the high reaction rates, i.e. although the particles had created so much oxygen, they hardly changed," summarises Tschulik. "The stability under extreme conditions is exceptional."

The analysis approach used in the current work can also be transferred to other electrocatalysts. "It is essential to find out more about the activities of nanocatalysts in order to be able to efficiently further develop non-precious metal catalysts for the renewable energy technologies of tomorrow," says the Bochum-based chemist. In order to analyse the effect of the particle size on the catalytic activity, it is important to synthesise nanoparticles with defined size. As part of the University Alliance Ruhr, the Bochum team cooperates closely with researchers from the University of Duisburg-Essen led by Professor Stephan Schulz, who produce the catalyst particles.

With increasing demand for food from the planet’s growing population and climate change threatening the stability of food systems across the world, University of Minnesota research examined how the diversity of crops at the national level could increase the harvest stability of all crops in a nation.

The research, published Wednesday in the journal Nature, examined 50 years of data (1961-2010) from the Food and Agricultural Organization (FAO) of the United Nations on annual yields of 176 crop species in 91 nations to determine how stable and predictable the food supply is in each country. This is the first research of its kind to examine the relationship between crop diversity and food stability at the scale of nations.

“We found an intriguing pattern — nations that grow more crops tend to have more stable food supplies,” said G. David Tilman, co-author of this study and director of the Cedar Creek Ecosystem Science Reserve in the College of Biological Sciences. “Our analysis also shows that nations with a variety of crops are less likely to experience a severe food shortage.”

That type of shortage is described as a year in which a nation has a 25% or greater decline in the total yield all of its crops combined. After examining the FAO data, Tilman and Delphine Renard — a postdoctoral researcher at the University of California Santa Barbara — found that:

nations with some of the lowest crop diversities experienced a severe food shortage about every eight years;
countries with some of the highest diversities of crops experienced a severe food shortage about every 100 years;
robust irrigation capabilities in nations also have significant stabilizing effects on crop production, leading to fewer years with severe food shortages.

The research suggests that nations that appropriately increase crop diversity may have more stable food supplies. In areas of the world where there are limited water resources or where increased irrigation is unaffordable, researchers suggest greater crop diversity may be particularly useful as it may allow farmers to not only help stabilize the food supply, but their income as well.

The research also found:

that the stability of a nation’s food supply depended on the types of crops grown, with grains and legumes seeming to lead to more stable food supplies;
food supply stability depended on having not just more crops, but rather having those crops be more evenly abundant;
heat waves harmed yields and stability and while fertilization greatly increased yields, it did not increase stability.

“Food supplies are expected to become less stable because of climate change,” Tilman said. “We encourage nations around the world to evaluate their crop diversity and determine if there might be some additional crops that would work well for them. Increasing crop diversity is one tactic to prepare for the potential impacts of climate change on crop production.”

Tilman suggests that alongside crop diversity planning, nations should consider the benefits of new drought-tolerant crop varieties, increased irrigation, intercropping and more transparent agricultural trade.

“There are 7.7 billion people on Earth and we all depend on a stable, global food supply,” said Tilman. “These tactics are just one of many we can follow to plan our future and better prepare future generations to live healthily on this planet.”

Future research needs to be taken to understand which types and combinations of crops better suit specific climates and soils to enhance food supply stability.

A new platform for speeding up and controlling the evolution of proteins inside living plants has been developed by a KAUST-led team.

Previously, this type of directed evolution system was only possible in viruses, bacteria, yeast and mammalian cell lines. The Saudi research--part of KAUST's Desert Agriculture Initiative--has now expanded the technique to rice and other food plants. It means that plant breeders now have an easy way to rapidly engineer new crop varieties capable of withstanding weeds, diseases, pests and other agricultural stresses.

"We expect that our platform will be used for crop bioengineering to improve key traits that impact yield and immunity to pathogens," says group leader Magdy Mahfouz. "This technology should help improve plant resilience under climate change conditions."

To experimentally build their directed evolution platform, Mahfouz and his colleagues used a combination of targeted mutagenesis and artificial selection in the rice plant, Oryza sativa. They took advantage of the gene-editing tool known as CRISPR to generate DNA breaks at more than 100 sites throughout the SF3B1 gene, which encodes a protein involved in the processing of other gene transcripts. After manipulating the DNA of small bundles of rice cells in this way, the researchers then grew the mutated seedlings in the presence of herboxidiene, a herbicide that normally targets the SF3B1 protein to inhibit plant growth and development.

This strategy ultimately yielded more than 20 new rice variants with mutations that conferred resistance to herboxidiene to varying degrees. In collaboration with Stefan Arold's group at the KAUST Computational Bioscience Research Center, Mahfouz and his colleagues then characterized the structural basis of the resistance--showing, for example, how particular mutations helped destabilize herbicide binding to the SF3B1 protein.

Herboxidiene is not widely used in industrial agriculture, but the same basic directed evolution strategy could now be used to design crops resistant to more common weed-killers. The herbicides would then eliminate unwanted surrounding plants while leaving the desired cultivated crop intact.

Breeders could also begin to evolve practically any trait of interest, notes Haroon Butt, a postdoctoral fellow in Mahfouz's lab. "This is a proof-of-principle study with wide applicability," says Butt, the first author of the paper that outlines the technology. "Our platform mimics Darwinism, and the selection pressure involved helps enforce the development of new gene variants and traits that would not be possible by any other known method."

Sigma receptors are proteins found on mainly the surface of endoplasmic reticulum (ER) in certain cells. Sigma-1 and sigma-2 are the two main classes of these receptors. The sigma-1 receptor is involved neurological disorders and certain types of cancer. To understand better how the receptor is involved in disease and whether drugs developed to target it are working, it is important to be able to accurately trace the sigma-1 receptor. Researchers at Kanazawa University have developed a probe, which can identify and latch onto the sigma-1 receptor.

The research team led by Kazuma Ogawa had previously developed molecules with such binding potential. However, upon detailed analysis of the sigma-1 receptor structure, they realized that extending the length of these molecules would increase their binding affinity further. The team therefore created molecules with varying lengths and found one probe that bound to the receptor exceptionally well. For measuring and mapping the sigma receptors by nuclear imaging, radiolabeled iodine was introduced into the probe. The structure created subsequently bound to both sigma-1 and sigma-2 receptors.

Since sigma-1 and sigma-2 receptors are involved in prostate cancer, the team then tested the effects of their newly created molecular probe on prostate cancer cells. These cells have sigma receptors and thus any probe with a high affinity will attach to them and enter the cell. As expected, the probe signal from within the cell was high. When haloperidol--a drug specific to the sigma-1 receptor--was added to the mix this signal dropped, suggesting a competition between the two.

To finally assess the affinity of the probe for different tissues within the body, mice with prostatic tumors were used. While the probe easily entered and stayed within the tumors, its presence in the muscles and blood was less. The probe was thus highly specific for tissues with the presence of sigma receptors.

This study reports a sophisticated probe that binds to sigma-1 receptors better than previous probes developed. This coupled with its ability to escape non-specific tissues is a promising step forward in studying changes induced in the sigma-1 receptor in various disorders. The probe can also be used when developing drugs against the sigma-1 receptor to compare the binding affinities of such drugs. "These results provide useful information for developing sigma-1 receptor imaging probes", conclude the researchers.

Blockchain Technology is known to be one of the top disruptive technologies of today that is driving the fourth industrial revolution. A blockchain, designed to be resistant to the modification of its data, offers security and privacy benefits that are well appreciated particularly by banks, governments and techno-corporations.

One of the ways that Blockchain Technology provides such security is through Proof of Stake (PoS). POS Blockchain protocols rely on voting mechanisms to reach consensus on the current state of data. If an enhanced majority of staking nodes, also called validators, agree on a proposed block of data, then this block is appended to the blockchain. Yet, these protocols remain vulnerable to faults caused by validators who abstain either accidentally or maliciously. In particular, while selecting staking nodes proportionally to their stake to form block-creating committees, current PoS protocols do not guarantee that selected committees will create blocks. This in turn violates the perceived fairness in the distribution of rewards in proportion to the stake of participating nodes.

To protect against such faults while retaining the PoS selection and reward allocation schemes, Singapore University of Technology and Design (SUTD) researchers studied weighted voting in validator committees. First, they introduced validators' voting profiles - this helps to quantify the probability that a validator will cast a correct vote based on the validator's previous contributions to date to the protocol. Then they defined the mathematical framework to apply optimal decision rules in committee voting. The researchers designed a generalised multiplicative weights algorithm to update individual validators' profiles according to their voting behaviour, consensus outcome and collective blockchain welfare as illustrated in table 1.

The result is a two-layered scheme in which selection of nodes and allocation of rewards are performed by the underlying PoS mechanism whereas blocks are decided by a weighted majority voting rule. This scheme improves consensus within selected committees by scaling votes according to validators' profiles without interfering with the PoS execution. Hence, it can be tested, implemented and reverted with minimal cost to existing users. The research paper also discussed potential issues and limitations of weighted voting in trustless, decentralised networks and related the results to the design of current PoS protocols.

The secret of platinum deposits revealed by novel field observations in the Bushveld Complex

Most of the world's economically-viable platinum deposits occur as 'reefs' in layered intrusions - thin layers of silicate rocks that contain sulphides enriched in platinum group elements which are so vital for the sustainable development of modern human society.

There are two competing ideas of how platinum deposits formed: the first involves gravity-induced settling of crystals on the chamber floor, while the second idea implies that the crystals grow in situ, directly on the floor of the magmatic chamber.

Through examining the Merensky Reef of the Bushveld Complex in South Africa, which hosts the lion's share of the world's platinum and other noble metals, Dr Sofya Chistyakova from the School of Geosciences of the University of the Witwatersrand and her collaborators have established that the crystals grow in situ, with its high platinum status being attained while all its minerals were crystallising along the cooling margins of the magma chamber. Their research was published in a paper in Scientific Reports.

One of the remarkable features of the Bushveld Complex is that at the time when the Merensky Reef was forming, some portions of its chamber floor were highly irregular due to circular depressions (potholes). Such potholes with the Merensky Reef are best exposed in underground exposures of platinum mines.

"Our key discovery is that the entire Merensky Reef package in these potholes may develop as a 'rind' covering all the chamber floor depressions and culminations, even where these are vertical or overhanging" says Chistyakova.

This finding points to no possibility for the Merensky Reef to be formed by crystal settling on the chamber floor because sinking crystals cannot penetrate the solid rocks that form the pothole's overhangs. This strongly supports the concept that the silicate minerals and sulphides of platinum deposits grow directly at the floor of magmatic chambers.

"This is the most fundamental conclusion of our work and it can probably be applied to platinum deposits in other layered intrusions as well as potentially extended to other types of magmatic deposits, for example, chromite and Fe-Ti-V magnetite ores in mafic-ultramafic complexes" says Chistyakova.

Good fortune and cutting-edge scientific equipment have allowed scientists to observe a Gamma Ray Burst jet with a radio telescope and detect the polarisation of radio waves within it for the first time - moving us closer to an understanding of what causes the universe's most powerful explosions.

Gamma Ray Bursts (GRBs) are the most energetic explosions in the universe, beaming out mighty jets which travel through space at over 99.9% the speed of light, as a star much more massive than our sun collapses at the end of its life to produce a black hole.

Studying the light from Gamma Ray Burst jets as we detect it travelling across space is our best hope of understanding how these powerful jets are formed, but scientists need to be quick to get their telescopes into position and get the best data. The detection of polarised radio waves from a burst's jet, made possible by a new generation of advanced radio telescopes, offers new clues to this mystery.

The light from this particular event, known as GRB 190114C, which exploded with the force of millions of suns' worth of TNT about 4.5 billion years ago, reached NASA's Neil Gehrels Swift Observatory on Jan 14, 2019.

A rapid alert from Swift allowed the research team to direct the Atacama Large Millimeter/Sub-millimeter Array (ALMA) telescope in Chile to observe the burst just two hours after Swift discovered it. Two hours later the team was able to observe the GRB from the Karl G. Jansky Very Large Array (VLA) telescope when it became visible in New Mexico, USA.

Combining the measurements from these observatories allowed the research team to determine the structure of magnetic fields within the jet itself, which affects how the radio light is polarised. Theories predict different arrangements of magnetic fields within the jet depending on the fields' origin, so capturing radio data enabled the researchers to test these theories with observations from telescopes for the first time.

The research team, from the University of Bath, Northwestern University, the Open University of Israel, Harvard University, California State University in Sacramento, the Max Planck Institute in Garching, and Liverpool John Moores University discovered that only 0.8% of the jet light was polarised, meaning that jet's magnetic field was only ordered over relatively small patches - each less than about 1% of the diameter of the jet. Larger patches would have produced more polarised light.

These measurements suggest that magnetic fields may play a less significant structural role in GRB jets than previously thought.

This helps us narrow down the possible explanations for what causes and powers these extraordinary explosions. The study is published in Astrophysical Journal Letters.

First author Dr Tanmoy Laskar, from the University of Bath's Astrophysics group, said: "We want to understand why some stars produce these extraordinary jets when they die, and the mechanism by which these jets are fuelled - the fastest known outflows in the universe, moving at speeds close to that of light and shining with the incredible luminosity of over a billion suns combined.

"I was in a cab on my way to O'Hare airport in Chicago, following a visit with collaborators when the burst went off. The extreme brightness of this event and the fact that it was visible in Chile right away made it a prime target for our study, and so I immediately contacted ALMA to say we were going to observe this one, in the hope of detecting the first radio polarisation signal.

"It was fortuitous that the target was well placed in the sky for observations with both ALMA in Chile and the VLA in New Mexico. Both facilities responded quickly and the weather was excellent. We then spent two months in a painstaking process to make sure our measurement was genuine and free from instrumental effects. Everything checked out, and that was exciting.

Dr Kate Alexander, who led the VLA observations, said: "The lower frequency data from the VLA helped confirm that we were seeing the light from the jet itself, rather than from the interaction of the jet with its environment."

Dr Laskar added: "This measurement opens a new window into GRB science and the studies of energetic astrophysical jets. We would like to understand whether the low level of polarisation measured in this event is characteristic of all GRBs, and if so, what this could tell us about the magnetic structures in GRB jets and the role of magnetic fields in powering jets throughout the universe."

Professor Carole Mundell, Head of Astrophysics at the University of Bath, added: "The exquisite sensitivity of ALMA and rapid response of the telescopes has, for the first time, allowed us to swiftly and accurately measure the degree of polarisation of microwaves from a GRB afterglow just two hours after the blast and probe the magnetic fields that are thought to drive these powerful, ultrafast outflows."

The research team plans to hunt for more GRBs to continue to unravel the mysteries of the biggest explosions in the universe.