Tech

Super Typhoon Maria's seven nautical-mile wide eye appeared very clearly in a visible image from NASA's Aqua satellite on July 6.

When NASA's Aqua satellite passed over the Northwestern Pacific Ocean on July 6 at 0350 UTC (July 5 at 11:50 p.m. EDT), the MODIS instrument or Moderate Resolution Imaging Spectroradiometer provided a visible-light image of Super Typhoon Maria. The MODIS image revealed a clear, small eye, surrounded by a powerful ring of strong thunderstorms.

At 11 a.m. EDT (1500 UTC) on July 6, 2018, the Joint Typhoon Warning Center (JTWC) noted that Super Typhoon Maria was packing maximum sustained winds near 155 mph (135 knots/250 kph). Maria was a strong Category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale. Maria's eye was centered near 17.0 degrees north latitude and 141.2 degrees east longitude, about 480 nautical miles south of Iwo To island, Japan. Maria was moving to the northwest at 4.6 mph (4 knots/7.4 kph).

At that time, the JTWC noted that the "sharply-outlined 7-nautical mile wide eye that has constricted over the past 12 hours. This reduction in eye diameter plus the formation of a secondary outer eye wall, as observed in recent microwave images, indicate the cyclone is undergoing an eye wall replacement cycle."

JWTC said that Maria is forecast to continue to move northwest. The system is intensifying rapidly, and will peak as a Category 5 hurricane on the Saffir-Simpson Hurricane Wind Scale at 161 mph (140 knots/259 kph) on July 14. The storm is expected to start weakening slowly on July 8 en route to the Ryuku Islands. Maria is forecast to speed toward Okinawa and pass just to its south, into the Yellow Sea and July 11 make landfall to the south of Shanghai near Taizhou, China.

Tropical Depression 2 strengthened into a compact hurricane on July 6 as NASA's Aqua satellite gathered temperature data on the storm.

At 2:30 p.m. EDT on July 5, the depression strengthened into Tropical Storm Beryl. At 5 a.m. EDT on Friday, July 6, Beryl became the first hurricane of the 2018 Atlantic hurricane season.

When NASA's Aqua satellite passed over the newly strengthened Hurricane Beryl on July 6 at 12:25 a.m. EDT (0425 UTC), the MODIS instrument or Moderate Resolution Imaging Spectroradiometer, analyzed the storm in infrared light. The infrared light provided temperature data that revealed how cold cloud tops were in the storm. The higher the cloud top, the colder, and the stronger the uplift in the storm. MODIS found coldest cloud top temperatures near minus 70 degrees Fahrenheit (minus 56.6 degrees Celsius) around the center, and as cold as minus 50 degrees Fahrenheit (minus 45.5 degrees Celsius) in fragmented bands of thunderstorms wrapping into the center.

Beryl is a compact hurricane. Hurricane-force winds extend outward up to 10 miles (20 km) from the center, and tropical-storm-force winds extend outward up to 35 miles (55 km).

The National Hurricane Center (NHC) noted at 11 a.m. EDT (1500 UTC), the eye of Hurricane Beryl was located near latitude 10.7 degrees north and longitude 46.5 degrees west.

Beryl was moving toward the west near 15 mph (24 kph). A faster westward to west-northwestward motion is expected to begin over the weekend and continue through early next week. On the forecast track, the center of Beryl will approach the Lesser Antilles over the weekend and cross the island chain late Sunday, July 8 or Monday, July 9. The estimated minimum central pressure is 994 millibars. Maximum sustained winds have increased to near 80 mph (130 kph) with higher gusts.

NHC cautioned that interests in the Lesser Antilles should monitor the progress of Beryl, as hurricane watches could be needed for some of the islands by tonight, July 6.

NHC said, "Additional strengthening is forecast during the next couple of days, and Beryl is expected to still be a hurricane when it reaches the Lesser Antilles late Sunday or Monday. Weakening is expected once Beryl reaches the eastern Caribbean Sea on Monday, but the system may not degenerate into an open trough until it reaches the vicinity of Hispaniola and the central Caribbean Sea."

Washington, DC - July 6, 2018 - Researchers have shown that higher levels of Plasmodium falciparum antibodies are protective against severe malaria in children living in Papua New Guinea. Children who have higher levels of antibodies to a specific short amino acid sequence in the malaria parasite, P. falciparum, have much lower rates of clinical and severe malaria. This amino acid sequence, an antigen, is similar among P. falciparum strains elsewhere in the world, suggesting that this antigen would make a good target for a malaria vaccine. The research is published in Infection and Immunity, a journal of the American Society for Microbiology.

This work shows that people who lack immunity to the malaria parasite are more likely to experience malaria symptoms. These people could be identified by their relative lack of antibodies to this antigen, said corresponding author Alyssa Barry, BSc (Hons), PhD, Associate Professor, and a group leader within the Population Health and Immunity Division, Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia.

That amino acid sequence, known among scientists as the ICAM1 binding motif, is critical to the virulence of the malaria parasite because it can bind to the tiniest blood vessels in the brain, known as the microvasculature. There the parasite remains hidden from the host's immune system, causing a severe case of cerebral malaria by blocking the blood vessels and causing inflammation. The ICAM1-binding motif can vary slightly in sequence and still bind tightly, and it is a strong candidate for a vaccine target. (image: P. falciparum gametocytes)

In the study, the investigators measured antibody responses to the ICAM1-binding motif. The subjects of this study were 187 children ages 1-3, from Papua New Guinea. Once the measurements were taken, the investigators followed the children for 16 months to determine the incidence of malaria over time.

Antibody responses to the ICAM1-binding motif were associated with 37 percent less risk of high-density clinical malaria during follow-up. (A high density of the parasite in an infection is necessary, but not sufficient to cause a severe case of malaria.) Children who had severe cases of malaria during follow-up showed significantly lower levels of antibody to those sequences.

Globally, more than 200 million cases of malaria occur annually, and the disease kills an estimated 400,000 annually, according to the report. Children are hardest hit.

Researchers at Kyushu University's Center for Organic Photonics and Electronics Research (OPERA) in Japan have demonstrated a way to split energy in organic light-emitting diodes (OLEDs) and surpass the 100% limit for exciton production, opening a promising new route for creating low-cost and high-intensity near-infrared light sources for sensing and communications applications.

OLEDs use layers of carbon-containing organic molecules to convert electrical charges into light. In normal OLEDs, one positive charge and one negative charge come together on a molecule to form a packet of energy called an exciton. One exciton can release its energy to create at most one beam of light, or photon.

When all charges form excitons that emit light, a maximum 100% internal quantum efficiency is achieved. However, the new technology uses a process called singlet fission to split the energy from an exciton into two, making it possible to exceed the 100% limit for the efficiency of converting charge pairs into excitons, also known as the exciton production efficiency

"Put simply, we incorporated molecules that act as change machines for excitons in OLEDs. Similar to a change machine that converts a $10 bill into two $5 bills, the molecules convert an expensive, high-energy exciton into two half-price, low-energy excitons," explains Hajime Nakanotani, associate professor at Kyushu University and co-author of the paper describing the new results.

Excitons come in two forms, singlets and triplets, and molecules can only receive singlets or triplets with certain energies. The researchers overcame the limit of one exciton per one pair of charges by using molecules that can accept a triplet exciton with an energy that is half the energy of the molecule's singlet exciton.

In such molecules, the singlet can transfer half of its energy to a neighboring molecule while keeping half of the energy for itself, resulting in the creation of two triplets from one singlet. This process is called singlet fission.

The triplet excitons are then transferred to a second type of molecule that uses the energy to emit near-infrared light. In the present work, the researchers were able to convert the charge pairs into 100.8% triplets, indicating that 100% is no longer the limit. This is the first report of an OLED using singlet fission, though it has previously been observed in organic solar cells.

Furthermore, the researchers could easily evaluate the singlet fission efficiency, which is often difficult to estimate, based on comparison of the near-infrared emission and trace amounts of visible emission from remaining singlets when the device is exposed to various magnetic fields.

"Near-infrared light plays a key role in biological and medical applications along with communications technologies," says Chihaya Adachi, director of OPERA. "Now that we know singlet fission can be used in an OLED, we have a new path to potentially overcome the challenge of creating an efficient near-infrared OLED, which would find immediate practical use."

Overall efficiency is still relatively low in this early work because near-infrared emission from organic emitters is traditionally inefficient, and energy efficiency will, of course, always be limited to a maximum 100%. Nonetheless, this new method offers a way to increase efficiency and intensity without changing the emitter molecule, and the researchers are also looking into improving the emitter molecules themselves.

With further improvements, the researchers hope to get the exciton production efficiency up to 125%, which would be the next limit since electrical operation naturally leads to 25% singlets and 75% triplets. After that, they are considering ideas to convert triplets into singlets and possibly reach a quantum efficiency of 200%.

The Auk: Ornithological Advances presents a study on a Northern Spotted Owl pedigree, consisting of almost 14,200 individuals over 30 years, which determined inbreeding varies across the species' range. Selection against inbreeding based on decreased future reproduction, fewer offspring, and overall survival of individuals was also supported. These results indicate that Spotted Owl conservation efforts need to address owl breeding more. Another implication of this work is the need to increase genetic diversity to prevent further population decline.

Mark Miller of the United States Geological Survey (USGS) Forest and Rangeland Ecosystem Science Center, and colleagues employed field and statistical methods to create a family tree for Northern Spotted Owls living in California, Oregon, and Washington. From this, the researchers determined how often inbreeding occurs in the wild for these birds. Fourteen types of matings among relatives were determined with most inbreeding relationships being between half or full siblings. It was discovered that inbreeding is most common in the Washington Cascades (~15% of individuals are inbred), while the lowest inbred population was Northern California (~2.7% of individuals). The explanation for this geographic variation may be the rate at which specific populations are declining and experiencing bottlenecks. Conservation efforts are vital today given that Northern Spotted Owls are already facing habitat loss and competition with a similar species, the Barred Owl. This study showed that both the physical consequences of inbreeding (physical deformities, reduced ability to adapt) and the reproductive fitness of individual birds (infertility, future reproduction, decreased survival) need to be taken into account since both influence this species' success. Translocating birds among populations to help increase the genetic diversity may be a potential management strategy.

Lead author Mark Miller comments, "Long-term studies, similar to the one described in this paper, are key to understanding how common or rare inbreeding is in natural populations. An understanding of the extent of inbreeding can help resource managers better identify appropriate measures to conserve threatened and endangered species."

Barcelona, 4 July 2018: The inclusion of nuts in a regular diet significantly improves the quality and function of human sperm, according to results of a randomised trial which measured conventional semen parameters and molecular changes over a 14-week study period. The findings, say the investigators, "support a beneficial role for chronic nut consumption in sperm quality" and reflect a research need for further male-specific dietary recommendations.

The results of the study are presented today by Dr Albert Salas-Huetos from the Human Nutrition Unit of the Universitat Rovira i Virgil in Reus, Spain.(1)

The study was performed, he said, against a background of general decline in quantity and quality of human sperm, attributed in industrialised countries to "pollution, smoking, and trends toward a western-style diet".(2) In this study subjects randomised to the nut group had significant improvements in their sperm count, vitality, motility and morphology (shape); these were consistent with improvements found in other recent studies with diets rich in omega-3, antioxidants (eg, vitamin C and E, selenium and zinc), and folate. Nuts are dense foods containing many of these nutrients and other phytochemicals.

The study was a 14-week randomised clinical trial in which 119 healthy young men aged 18-35 were allocated to either their usual western-style diet supplemented with 60 grams/day of mixed almonds, hazelnuts and walnuts, or their usual western-style diet without nuts. In its analysis the study recorded not just sperm parameters (according to WHO benchmarks) but also changes in several molecular factors, including sperm DNA fragmentation.(3) Sperm and blood samples were analysed at baseline and after 14 weeks of intervention.

Results firstly found significantly higher levels of sperm count, vitality, motility and morphology in the men randomised to the 60 g/day nut diet than in those following their usual diets free of nuts. Improvements in the former group were by around 16% in sperm count, 4% in sperm vitality, 6% in sperm motility, and 1% in morphology. These four parameters, explained Salas-Huetos, are all associated with male fertility. Moreover, the subjects in the nut group also showed a significant reduction in their levels of sperm DNA fragmentation, a parameter closely associated with male infertility. Indeed, it was this change in the level of DNA fragmentation in the sperm cells by which the investigators explained, at least in part, the improvement in sperm count, motility and morphology.

Although these are statistically significant results from a randomised trail with a high level of scientific evidence, Salas-Huetos emphasised that subjects in the study were all healthy and apparently fertile men following a western-style diet. He thus warned that results cannot be extrapolated to the general population.

So should men hoping to conceive a baby - either naturally or with IVF - add nuts to their everyday diet? "We can't yet say that," said Salas-Huetos, "based solely on the results of this study. But evidence is accumulating in the literature that healthy lifestyle changes such as following a healthy dietary pattern might help conception - and of course, nuts are a key component of a Mediterranean healthy diet."

India will need to feed approximately 394 million more people by 2050, and that's going to be a significant challenge. Nutrient deficiencies are already widespread in India today--30 percent or more are anemic--and many regions are chronically water-stressed. Making matters worse, evidence suggests that monsoons are delivering less rainfall than they used to. But a study published today in Science Advances shares a brighter outlook: replacing some rice with less thirsty crops could dramatically reduce water demand in India, while also improving nutrition.

Starting in the 1960s, a boom in rice and wheat production helped reduce hunger throughout India. Unfortunately, this Green Revolution also took a toll on the environment, increasing demands on the water supply, greenhouse gas emissions, and pollution from fertilizer.

"If we continue to go the route of rice and wheat, with unsustainable resource use and increasing climate variability, it's unclear how long we could keep that practice up," says Kyle Davis, a fellow at Columbia University's Earth Institute and lead author on the new study. "That's why we're thinking of ways to better align food security and environmental goals."

The study addresses two key objectives of the Indian government: to reduce undernourishment and improve nutrition, and to promote sustainable water use.

A Grain of Truth

Davis and his colleagues studied six major grains currently grown in India: rice, wheat, maize, sorghum, and pearl and finger millet. For each crop, they compared yield, water use, and nutritional values such as calories, protein, iron, and zinc.

They found that rice is the least water-efficient cereal when it comes to producing nutrients, and that wheat has been the main driver in increasing irrigation stresses.

The potential benefits of replacing rice with alternative crops varied widely between different regions, depending on how much the crops could rely on rainfall instead of irrigation. But overall, the researchers found that replacing rice with maize, finger millet, pearl millet, or sorghum could reduce irrigation water demand by 33 percent, while improving production of iron by 27 percent and zinc by 13 percent.

In some instances, those improvements came with a slight reduction in the number of calories produced, because rice has been bred to have higher yields per unit of land. So in some regions there's a tradeoff between water and land use efficiency, but Davis thinks that with more attention from scientists, the alternative crops could develop higher yields as well. For now, rice replacement isn't a one-size-fits-all solution, but something that should be evaluated on a case-by-case basis for each district, he said.

Going Against the Grain

While the findings are promising, the authors stop short of making policy recommendations--yet. First, says Davis, they'd like to add other variables into the analysis, including greenhouse gas emissions, climate sensitivity, and how much labor and money it takes to grow each crop.

In addition, the team wants to study Indian food preferences, to see if people would be willing to incorporate more of these alternative cereals into their diets. Davis is hopeful; "There are places around India where these crops continue to be consumed in pretty large amounts," he says, "and there were even more a generation or two ago, so it's still within the cultural memory."

India's state-run Public Distribution System (PDS) could be an ally in influencing consumer preferences. PDS currently subsidizes rice and wheat to support smallholder farmers and low-income households. Those subsidies have given incentives to farmers and consumers to plant and buy those crops, but future policies could help to encourage the use of the more nutritious, water-saving cereals like millet and sorghum.

Momentum is growing in support of alternative grains. Some Indian states are have already started pilot programs to grow more of these crops, and the Indian government is calling 2018 the 'Year of Millets.'

"If the government is able to get people more interested in eating millets, the production will organically respond to that," says Davis. "If you have more demand, then people will pay a better price for it, and farmers will be more willing to plant it."

This week, we see the first papers in PLOS Medicine's Special Issue on Climate Change and Health being published, advised by Guest Editors Jonathan Patz, the Director of the Global Health Institute at the University of Wisconsin-Madison and the John P. Holton Chair in Health and the Environment with appointments in the Nelson Institute for Environmental Studies and the Department of Population Health Sciences, USA and Madeleine Thomson, a Senior Research Scientist at the International Research Institute for Climate and Society (IRI) and Senior Scholar at the Mailman School of Public Health, Department of Environmental Health Sciences, Columbia University, New York, USA.

In a research article, Christopher Weyant of Stanford University, USA and colleagues predict reduced crop nutritional content and subsequent health disparities due to increased carbon dioxide levels associated with climate change. In their country-level modelling study, the authors incorporate estimates of climate change, crop nutrient concentrations, dietary patterns and disease risk into a model of iron and zinc deficiency. Their estimates predict a disease burden of approximately 125.8 million disability-adjusted life-years (DALYs) globally over the period from 2015 to 2050, disproportionately affecting South-East Asian and sub-Saharan African countries.

In a Perspective article, Kristie Ebi of the University of Washington, USA and Lewis Ziska of the Department of Agriculture-ARS, Adaptive Cropping Systems Laboratory, Mississippi, USA continue the theme of crop nutrition in a changing climate and how rising carbon dioxide concentrations and climate change are expected to decrease the quality, quantity, and availability of rice, wheat, potatoes and other staple crops. They outline major knowledge gaps and investments needed to protect population health, particularly among the most vulnerable.

Turning to the effects of climate change on demands for increased air conditioning, a primary adaptation to climate change, David Abel of the University of Wisconsin Madison, USA and colleagues predict future mortality associated with increased emissions from power plants caused by demand for air conditioning. Their modelling study considers different climate increases with or without adaptation. They predict increases of 4.8% and 8.7% respectively for particulate- and ozone-associated deaths above climate change impacts alone. Policy advisors and building planners may need to consider energy conservation, building design and other measures to tackle future dependence on buildings' cooling systems.

China is the world's biggest greenhouse gas emitter and the most populated country, and its population structure is undergoing change and aging. In a study looking at ozone emissions and population change projections, Patrick Kinney of Boston University, USA and Kai Chen of Helmholtz Institute, Munich, Germany show future changes in ozone-related acute mortality from 2013-2015 to 2053-2055 under different climate and population change scenarios in 104 cities across China. Climate change and an aging population may lead to increases of 1-4 fold for ozone-related deaths in 2053-2055. Mitigation policies are urgently needed.

The Special Issue will provide a venue for data-rich research focused on climate-related impacts, adaptation and mitigation, with research and discussion articles appearing over the next few weeks.

TALLAHASSEE, Fla. -- In pharmacology, not all molecular structures are created equal. Some frameworks are overrepresented in nature, making them especially attractive to scientists on the hunt for more effective drugs.

One such structure, known to scientists as the carbocyclic 5-8-5 fused ring system, is notoriously difficult to produce using conventional laboratory methods, and researchers have therefore been largely unable to tap into its potentially broad therapeutic potential.

Now, an innovative synthetic technique developed by Florida State University chemists could unlock these elusive structures, opening the door to a new world of cutting-edge medicinal compounds.

In a study published in the journal Chemical Science, FSU researchers detail a novel, modular scheme for producing large quantities of the 5-8-5 ring structure. A synthesis process that was once exceptionally labor- and resource-intensive, they discovered, could be streamlined into four relatively straightforward steps.

"The ubiquity of the 5-8-5 ring system within natural products caught our attention," said lead author James Frederich, an assistant professor in the Department of Chemistry and Biochemistry. "Our chemistry provides an attractive entry point to natural products harboring a 5-8-5 ring system."

Considered by chemists to be a possible example of a "privileged scaffold" -- an atomic arrangement that recurs frequently in biologically active compounds -- the 5-8-5 framework is composed of two five-sided molecular rings fused to a central 8-sided ring. This unique architecture constitutes the core of more than 30 natural products, several of which have useful, potentially therapeutic effects in human cell cultures.

Existing methods for producing this framework in a lab were limited by impractically protracted synthesis processes requiring high temperatures and transition metal catalysts. Frederich's approach sidesteps these hurdles. In his system, cyclization substrates -- the underlying structures upon which the ring frameworks are built -- can be accessed via a simple two-step assembly scheme. With a reliable substrate in place, the full 5-8-5 scaffold is accomplished in one, highly controlled operation with UV light employed to promote ring formation.

"The use of UV light is particularly convenient as it avoids the need for high temperatures or costly catalysts," Frederich said.

Frederich's strategy is a significant improvement on current approaches to 5-8-5 ring structure synthesis. He said the simplified, high-yielding methodology will aid scientists as they work to better understand the possible medicinal properties of synthetic products built upon the 5-8-5 scaffold.

In particular, Frederich said these compounds could help stabilize protein-protein interactions -- the physical mingling of protein molecules that govern biological processes within a cell.

"We speculate that the 5-8-5 ring system can support a range of designed, non-natural structures with interesting properties in human cell culture," he said. "We expect to leverage this chemistry to build and test certain structures that have been shown to modulate protein-protein interactions."

Batrachochytrium dendrobatidis (Bd), known as chytrid fungus, has long been known to cause the decline and extinction of numerous species of frogs, toads, salamanders and other amphibians on several continents.

Chytrid is found around the world, but until recently it has been unclear where the pathogen originated. New research has now traced its source to East Asia.

The results were published in the journal Science. Researchers at Imperial College London and several partners, including the Norwegian University of Science and Technology's NTNU University Museum, carried out the study.

Enhanced biosafety recommended

The researchers highlight the need for more stringent biosafety guidelines across national borders, including a possible ban on trade in amphibians as pets to ensure the survival of vulnerable species.

"Biologists have known since the 1990s that Bd is behind the decline for many amphibian species. But until now, we haven't been able to identify exactly where it came from," says first author Simon O'Hanlon of Imperial College London.

"In our article we solve this problem and show that the lineage that has caused this devastation can be traced back to East Asia," he says.

Chytrid spreads rapidly in the wild and travels from animal to animal. The fungus causes catastrophic mortality and decline in some species, while others are less affected.

The fungus causes a disease called chytridiomycosis. The disease attacks the animal's skin, which affects its ability to regulate water and electrolyte levels and leads to heart failure.

International cooperation

In this latest study, 38 institutions formed an international team that gathered pathogen samples from all over the world. They sequenced the genomes of the samples and combined the new data with the genomes of previous Bd studies to make a collection of 234 samples.

The researchers analysed the data and looked at differences between the genomes. From the samples, they identified four main genetic lineages of the fungus, of which three were found globally. A fourth line was found only in Korea, on frogs that were native to the region.

Commercial pet trade spreads infectious agent

The researchers' finding supports the hypothesis that instead of dating back thousands of years, as previously thought, the disease range has greatly expanded only in the last 50 to 120 years. This coincides with the rapid global expansion of intercontinental trade.

The researchers believe that human movement of amphibians through the pet trade has directly contributed to spreading the pathogen around the world. They add that the paper provides a strong argument for banning trade in amphibians from Asia, due to the high risk associated with exporting previously unknown strains of chytrid out of this region.

The group highlights the threat of another amphibian pathogen that also emerged from Asia (B. salamandrivorans or BSal), which affects salamanders in Europe. The spread of this pathogen is also connected to the global trade in pet amphibians from Asia.

NTNU contribution to study

"The NTNU University Museum contributed to the study by sequencing the genes of frogs infected by the chytrid bacteria found in the museum collections," says associate professor Michael D. Martin in NTNU's Department of Natural History.

Martin notes that the museum's scientific collections provide valuable historical material that allows researchers to look back in time and carry out genetic studies of evolution. These collections are also an extremely valuable source of genetic information from places that are otherwise difficult to travel to and gather fieldwork samples from.

Analysing nearly four decades of archive footage from the Tour of Flanders, researchers from Ghent University have been able to detect climate change impacts on trees. Their findings were published today in the journal Methods in Ecology and Evolution.

Focusing on trees and shrubs growing around recognisable climbs and other 'landmarks' along the route of this major annual road cycling race in Belgium, the team looked at video footage from 1981 to 2016 obtained by Flemish broadcaster VRT. They visually estimated how many leaves and flowers were present on the day of the course (usually in early April) and linked their scores to climate data.

The ecologists found that the trees had advanced the timing of leafing and flowering in response to recent temperature changes. Before 1990, almost no trees had grown leaves at the time of the spring race. After that year, more and more trees visible in the television footage - in particular magnolia, hawthorn, hornbeam and birch trees - were already in full leaf.

These shifts were most strongly related to warmer average temperatures in the area, which have increased by 1.5°C since 1980.

"Early-leafing trees can be good news for some species as they grow faster and produce more wood", says Prof. Pieter De Frenne from Ghent University, lead author of this study. "However, their leaves also cast shadows. When trees flush earlier in the year, they shadow for a longer period of time, affecting other animals and plants, and even whole ecosystems."

"Some of the flowers growing under these trees may not be able to receive enough sunlight to bloom. As a result, insects can go without nectar and may struggle to find enough spots to sunbathe", he adds.

Phenology - the study of natural phenomena that recur periodically such as leafing and flowering - is mostly based on long-term observations and repeat photography, with data often being biased towards common species or geographical regions. In this study, archive footage allowed the researchers to use previously unexploited records of twelve tree species in the Flanders region in order to build long-term datasets of phenological responses.

"Our method could also be used to collect data on other aspects important for ecological or evolutionary research, such as tree health, water levels in rivers and lakes, and the spread of invasive species. Only by compiling data from the past will we be able to predict the future effects of climate change on species and ecosystems", De Frenne comments.

Television footage of cycling races lends itself well to research as these have relatively fixed routes and are organised around the globe, providing an opportunity to study a diverse range of species and locations that are currently understudied.

De Frenne points out that researchers could also take advantage of video material from other annual sports events such as marathons, golf tournaments and rally races, or even news coverage featuring open-air concerts or iconic landmarks surrounded by trees.

Podcast pre-embargo link: https://soundcloud.com/cmajpodcasts/170920-view

Community-based health care providers, such as physicians, nurse practitioners and others, should be aware of services and resources to help people living at home with dementia as well as their caregivers. A review in CMAJ (Canadian Medical Association Journal) aims to provide guidance to health care providers as well as government and health system planners, based on recent evidence.

"All health care providers should be aware of their local resources for dementia and which services may be most beneficial for their patients and caregivers," writes Dr. Dallas Seitz, Queen's University, Kingston, Ontario, with coauthors. "Health system planners and policy-makers should be aware of services that have been shown to be beneficial for people and plan to meet the increasing demand for these services in the future."

In Canada, over 500 000 people are affected by dementia, and society spends $15 billion annually caring for this population.

Highlights of the review:

Early detection of dementia is an important first step for accessing services by proactively identifying people at risk (case finding) rather than through broad population screening programs. Identifying dementia early can relieve stress and uncertainty for patients and their caregivers and facilitate early connection to supports.

Evaluation for dementia should include patient history of cognitive and functional changes, medication review, cognitive screening tests, blood work and neuroimaging in some situations.

Community-based supports, such as in-home support services, caregiver education and training, respite programs and more, have been shown to delay admission to long-term care facilities.

Caregiver education programs and coordination of care have been effective at delaying placement in homes and are cost-effective.

Reducing caregiver stress is important for keeping people at home as long as possible.

Referral to dementia specialists may need to be selective, given the limited number of specialists and the increasing number of people with dementia. Referrals should be made when there is diagnostic uncertainty, marked change in a person's behaviour, challenges with medication and other complicating problems.

Some parts of Canada may currently have limited access to supports mentioned in the review.

"The identification and care of community-dwelling people with dementia and their caregivers is complex and will often involve multiple supports and services to optimize outcomes. Existing guideline recommendations for dementia and high-quality evidence underscore that community-level multicomponent supports, including caregiver education and training programs, some forms of respite programs and case management approaches for dementia, are effective in delaying admission to long-term care settings for older adults with dementia and reducing caregiver stress," the authors conclude.

"Care of community-dwelling older adults with dementia and their caregivers" is published July 3, 2018.

A biological switch that reliably turns protein expression on at will has been invented by University of Bath and Cardiff University scientists. The switch enables control of genome editing tools that might one day regulate cascades of desired genetic changes through entire populations.

This new switching method should work for any protein in any species and uses a cheap, non-toxic amino acid as the control switch - the 'on' mode requires the presence of an amino acid called BOC.

In contrast to other reported switches, this method does not use antibiotics, removing risks of selecting for bacterial antibiotic resistance, and neither is it 'leaky' - a situation in which proteins are expressed even when in 'off' mode, a problem faced by current methods that depend on temperature or light. The switch, an amino acid similar to lysine, is cheap, plentiful, non-toxic and should be environmentally-friendly.

The research teams in Bath and Cardiff successfully demonstrated the switch in both cultured cells and in early-stage mouse embryos without any detectable target protein expression activity in the absence of BOC.

The method extends a principle called genetic code expansion. To demonstrate the principle the team used transgenic mice carrying a gene that makes their skin glow green under UV light. When the genetic code expansion toolkit adapted for genome editing was present in embryos from the mice, their genomic DNA was efficiently edited to remove the fluorescence gene, but only when BOC was present. In the absence of BOC, no editing occurred. Embryos edited in this way could develop into mice that did not fluoresce, but without BOC no editing had occurred, so these mice remained green.

The study is published in the journal Scientific Reports.

The switch offers the potential to control a host of biological processes with the addition of BOC. These may include research and practical applications, in the laboratory test-tube, whole animals or both. For example, it might be used to address how certain proteins effect aging of cells in culture or animals. Clinically, it may provide a means to switch on proteins to enhance regenerative processes and could offer a new tier of control in gene therapy.

One exciting potential application would be in using the switch in gene drive technology. Gene drives can use the CRISPR-Cas9 system in a way that ensures all offspring in sexually reproducing species inherit a particular genetic segment, overcoming the 50% chance of inheritance that sexual reproduction might otherwise confer upon it.

Characteristics endowed by a gene drive can spread rapidly through a population regardless of whether or not they are advantageous - for instance trials have been done using gene drives to spread genes in mosquitoes that make females infertile, intending to crash the population of the malaria-spreading insect.

However, multiple challenges must be met before gene drive usage is likely to be authorised. Once initiated, they are difficult or impossible to control and may work over wider areas than desired, for example straying across international borders. They may have unintended environmental consequences or give rise to resistance. Regulating gene drives by making Cas9 BOC-switchable promises to ameliorate these problems.

Professor Tony Perry, who led the Bath team from the Department of Biology & Biochemistry, said: "Our switch is a way of controlling the expression of any protein via genetic code expansion.

"What sets our work apart is the potential for this as an environmentally friendly switch across large distances, which no previous method really enables. For example you can imagine controlling gene drive activity in livestock herds by adding or removing BOC from feedstuffs as required.

"Gene editing has enormous potential across biological science, from biomedicine to food security, in insects, plants and animals."

Co-author, Dr Yuhsuan Tsai from Cardiff said: "Although BOC provides an attractive and promising means to control editing, we are now working to address remaining challenges and iron out wrinkles in the system."

Barcelona, 3 July 2018: An add-on treatment commonly offered to female IVF patients to improve their chance of success has been shown in a large randomised trial to be of no value. "Endometrial scratch", a technique whereby a small scratch or tissue biopsy is made to the lining of the uterus prior to IVF, was associated with no improvements in pregnancy or live birth rates, and should, say an international team of investigators, be abandoned as a procedure by fertility clinics.

The results of the study are presented today in Barcelona at the 34th Annual Meeting of ESHRE by Dr Sarah Lensen, a researcher from the University of Auckland, New Zealand.

The study was a large randomised trial performed at 13 fertility centres in five countries (New Zealand, UK, Belgium, Sweden and Australia) and involving more than 1300 women having IVF. One half were randomly assigned to endometrial scratching and the other to no adjuvant procedure. The scratch was performed with a Pipelle cannula, a small flexible plastic tube commonly used for performing uterine biopsy for a variety of indications. In IVF, where some studies have shown a benefit in outcome, it's been proposed that injury to the lining of the uterus causes an inflammatory response conducive to implantation following embryo transfer.

"Results from earlier studies have suggested a benefit from endometrial scratching in IVF," explained Lensen, "especially in women with previous implantation failure. However, many of these studies had a high risk of bias in their design or conduct and did not provide strong evidence. There was still uncertainty about the validity of a beneficial effect."

Women in the endometrial scratch arm of the study had a Pipelle biopsy between day 3 of the preceding cycle and day 3 of the IVF/embryo transfer cycle. Controls had no intervention. Results showed that clinical pregnancy rate in the endometrial scratch group was 31.4% and in the control group 31.2%; live birth rates were 26.1% in the former and 26.1% in the latter. The probabilities of pregnancy were still comparable after controlling for variables and sub-group analysis, which included patients with a history of implantation failure in IVF (defined as two or more unsuccessful embryo transfers). This group in earlier studies has appeared to gain particular benefit from the procedure.

This latest study also measured pain discomfort score associated with endometrial scratch and found "a moderate amount of pain and bleeding". This too, said the investigators, was further reason why endometrial scratch should be abandoned and removed from the list of IVF adjuvant options.

Endometrial scratch is a reportedly common add-on treatment in fertility clinics. A survey of clinics in Australia, New Zealand and UK performed by Lensen and colleagues in 2016 found that 83% of clinicians would recommend endometrial scratching prior to IVF, especially to women with recurrent implantation failure.(1)

"Our results contradict those of many studies published previously," said Lensen, "and, although our trial was the largest and most robust study undertaken so far, it can be difficult for one trial to change practice. However, there are other trials under way at the moment, including two large studies from the Netherlands and UK. Nevertheless, even based just on our results, I think clinics should now reconsider offering endometrial scratch as an adjuvant treatment."

Chemical engineers at Rice University and Pennsylvania State University have shown that combining machine learning and quantum chemistry can save time and expense in designing new catalysts.

"Large amounts of data are generated in computational catalysis, and the field is starting to realize that data science tools can be extremely valuable for sifting through high-volume data to look for fundamental correlations that we might otherwise miss," said Rice's Thomas Senftle, co-author of a new study published online this week in Nature Catalysis. "That's what this paper was really about. We combined well-established tools for data generation and analysis in a way that allowed us to look for correlations we wouldn't otherwise have noticed."

A catalyst is a substance that accelerates chemical reactions without being consumed by them. The catalytic converters in automobiles, for example, contain metals like platinum and palladium that aid in reactions that break down air pollutants. Catalysts are a mainstay of the chemical and pharmaceutical industries, and the global market for catalysts is estimated at $20 billion per year.

The metals used in catalytic converters are typically part of a wire mesh. As hot exhaust passes through the mesh, the metal atoms on the surface catalyze reactions that break apart some noxious molecules into harmless byproducts.

"That's a gas phase reaction," Senftle said of the catalytic converter example. "There's a certain concentration of gas-phase species that come out of the engine. We want a catalyst that converts pollutants into harmless products, but different cars have different engines that put out different compositions of those products, so a catalyst that works well in one situation may not work as well in another."

The practice of flowing reactants past a catalyst is also common in industry. In many cases, a catalytic metal is attached to a solid surface and reactants are flowed over the surface, either as a liquid or a gas. For industrial processes that make tons of products per years, improving the efficiency of the metal catalyst by even a few percent can translate into millions of dollars for companies.

"If you have a clear picture of the properties of the metal catalyst and the substrate material the metal attaches to, that allows you to basically narrow down your search at the beginning," Senftle said. "You can narrow your design space by using the computer to explore which materials are likely to do well under certain conditions."

Senftle, assistant professor in chemical and biomolecular engineering at Rice, began the newly published research while still a graduate student at Penn State in 2015, along with lead authors Nolan O'Connor and A.S.M. Jonayat and co-author Michael Janik. They started by using density functional theory to calculate the binding strengths of single atoms of many different kinds of metals with a range of metal oxide substrates.

"The binding energy between the metal and substrate is of particular interest because the stronger the bond, the less likely the metal atom is to dislodge," Janik said. "If we can control that binding energy, we can tailor the size distribution of these metal particles, and that, in turn, is going to impact the overall reaction that they can catalyze."

O'Connor said, "We were curious about the properties of individual metal atoms and oxide surfaces that made for strong interacting pairs, which is a property we can use to design robust catalysts."

Along with the list of binding energies, the team had a catalog of about 330,000 additional properties for each of the metal-substrate combinations, including factors like oxide formation energy, coordination number, alloy formation energy and ionization energy.

"The machine learning algorithm looks for the combinations of those descriptors that correlate with the observed data on binding energies," Jonayat said. "It basically allows us to ask, 'Of all of these descriptors, how can we find the ones that correlate with the observed behavior in which we're interested?"

He said identifying such correlations can streamline catalyst design by making it possible to predict how materials will behave prior to laboratory testing that can be both expensive and time-consuming. Machine learning also can identify interesting effects that are worthy of additional study.

For example, Senftle said one correlation that kept appearing in the study was the importance of the direct interaction between the catalytic metals and the metal atoms in the support. He said this was unexpected because the metals typically each have a strong affinity to bind with oxygen as opposed to binding with each other.

"Originally, the idea was that it was the oxygen that was important," Senftle said. "We were interested in determining how well these two different metals shared the oxygen. But this direct interaction between the metals themselves kept popping up in our calculations, and it played a much larger role in dictating the overall behavior of the system than we had anticipated."

Senftle said he'd like to build on the complexity of the simulations in future research.

"Here we were looking at the interactions between the metals and the supports in a pristine environment with no water molecules or impurities of any kind," he said. "In reality, catalysts are used in very complicated reaction environments, and we'd like to examine how these trends change in those settings. For example, if this were an aqueous environment, water or dissociated water would likely adsorb on the surface. Those are going to impact the interaction, because now you have another player that is sharing the electron density and sharing the surface oxygens."