Tech

Everyone knows 2 + 2 = 4, but what about mosquitoes plus malaria? Lauren Childs, an assistant professor in the Department of Mathematics at Virginia Tech, says there's an equation for that too.

Childs recently co-authored a report with a team from Harvard University on the role of natural mosquito behavior on transmission of a disease that threatens half the world's population.

The study, "Multiple blood feeding in mosquitoes shortens the Plasmodium falciparum incubation period and increases malaria transmission potential," was published in the December 2020 issue of PLOS Pathogens.

"Worldwide there are about 400,000 deaths and 200 million cases each year from malaria," said Childs, a faculty member with the Virginia Tech College of Science who last year was named the Cliff and Agnes Lilly Faculty Fellow by the Board of Visitors. "About 50 percent of the world's population lives in an area that has consistent malaria transmission, so while it's not heard much about here in the U.S., it's certainly a huge problem."

One of the oldest and most varied parasites in the world -- more than 200 species exist today -- Plasmodium, the parasite that causes malaria, is transmitted through the millennia-old interaction between mosquitoes and humans. Plasmodium falciparum is considered the most virulent species.

Efforts to study this interplay solely in nature can be problematic due to constantly changing conditions known as "feedbacks": population of males vs. females, water tables for larval development, food sources, weather, and so forth.

"All these complicated pieces, mathematically we can put them all into a system and see how that feedback affects the next level and the next level so we can think about it quantitatively and make predictions," said Childs, who's also an affiliated faculty member of the systems biology program within the Academy of Integrated Science, also part of the College of Science.

According to Childs' team's study, while a mosquito ingests the parasite in a "blood meal" by biting an infected person, it typically takes about 10 to 14 days -- known as the "extrinsic incubation period" or EIP -- until the parasites appear in the mosquito's salivary glands where it can then be transmitted to another human.

Current common mitigation efforts include: a) killing of mosquitoes with insecticides, b) encouraging mosquitoes to feed on nearby animals rather than people and; c) genetically engineered drives to reduce mosquito egg production. 

But these strategies may be counter-productive.

According to Childs' research, "providing a second blood meal to female mosquitoes 3 days after they became infected ... dramatically increased the size of developing parasites and accelerated the appearance of transmissible forms in the salivary glands, shortening the EIP by 2.3 days (21 percent) and making these mosquitoes infectious sooner."

Furthermore, Childs said, reducing the number of eggs a female produces likely gives parasites more nutritional resources to grow and thus shortening the EIP.

"Malaria is a highly complex disease governed by the interplay of human and ecological factors, vector competence, infrastructure and others," said Igor V. Sharakhov, a professor of entomology in the Virginia Tech College of Agriculture and Life Sciences. "The development of predictive mathematical models can guide formation of malaria control measures. The modeling framework and analysis support policy-driven efforts to control and possibly eradicate malaria on a large scale."

Childs' work in applied mathematics began as an undergraduate when she took an interdisciplinary class that used quantitative ideas like oscillation and dynamics to answer questions in nature, such as how a population of fireflies achieve synchronized flashing.

As a post-doctoral researcher in Harvard University's T.H. Chan School of Public Health, Childs used her mathematical expertise to help infectious diseases and epidemiology specialists -- connections that continued after she joined Virginia Tech's math department in 2016.

"Collaborating with Lauren is always a pleasure as she really enables us to communicate the impact and relevance of our biological studies in the wider world," said Harvard research scientist W. Robert Shaw, who served as first co-author on the study. "I think of her as multilingual, working at the intersection of mathematics and mosquito and parasite biology. It's her ability to distill and translate complex behaviors and life cycles into a simplified mathematical framework that is such a rare talent and so valuable to our research."

Added Harvard Ph.D. candidate and study team member Inga Holmdahl: "Lauren has mentored me on a variety of different projects relating mosquito biology and malaria epidemiology over the past couple of years, using a mathematical and ecological framework. This is necessarily interdisciplinary and critical for allowing us to interpret biological findings in the context of malaria epidemiology." 

A professed fan of puzzles and games, Childs wields her math skills on the frontlines of other infectious disease fights. Some of her work in 2020 focused on the probability of asymptomatic spread by someone infected by COVID-19.

"Many people can see the next move in a game of chess," she said, "but the one that is 20, 30, or 50 moves ahead is much harder to see. You can use mathematics to calculate what possibilities there are."

Prisons with more green space have lower levels of violence and self-harm, according to new research at the University of Birmingham and Utrecht University.

The study is the first to attempt large-scale mapping of green space within prison environments and link it to well-being in a robust, statistically significant way. The results are published in Annals of the American Association of Geographers.

The researchers used GIS mapping to identify the percentages of green space (such as trees, lawns and shrubbery) within prisons in England and Wales. They compared this with available data about incidents of self-harm, prisoner assaults on staff and violence between prisoners. They also drew on information about the age and function of individual establishments - for example their capacity, what the security level was, whether they accommodated men, women or young offenders, and whether they were purpose-built prisons, or converted from other types of buildings such as military bases.

Their findings showed that taking all of these factors into account, prisons with a higher presence of green space had lower levels of self-harm, and lower levels of prisoner-on-prisoner violence and assaults on prison staff.

The study is significant since it demonstrates that the beneficial effects of nature contact, already recognised in other institutional contexts such as hospitals and schools, are also to be found in prisons. Self-harm and violence are currently at very high levels in prisons in England and Wales, with over 61,000 incidents of self-harm in the 12 months to September 2019. Over the same period, there were more than 33,000 incidents of violence between prisoners, and more than 10,000 assaults on staff.

While it is not possible to calculate the personal and emotional costs of these incidents, the costs of hospital treatment from self-harm amount to some £2.7 million, while the costs of litigation arising from violent incidents are also significant. Her Majesty's Prison and Probation Service has not disclosed the full costs of legal actions, but has paid out £85 million in litigation claims between 2016 and 2019.

The team's findings, shared with the Ministry of Justice ahead of publication, therefore show that through improving wellbeing, increasing green spaces within prisons should also help in terms of managing costs and minimising staff absence.

Lead researcher, Professor Dominique Moran, of the University of Birmingham's School of Geography, Earth and Environmental Sciences, says: "Our evidence shows clear and demonstrable benefits from the presence of green space for prisoners in all categories of prison. It's clear that inclusion of green space should be a key design element for new prisons, and existing prisons should convert existing outdoor areas to provide more green space wherever possible."

A new report shows that British citizens who are missing abroad were more than twice as likely to be found by UK police as police in the country of disappearance.

Research by the Centre for the Study of Missing Persons (CSMP) at the University of Portsmouth also shows they were likely to be missing for much longer than if they'd disappeared in the UK.

The study found that British people who vanish abroad tend to be missing for extended periods, on average 134 days. This compares with 88 percent of people who go missing in the UK being found within the first 48 hours.

Dr Karen Shalev-Greene, Director of the Centre for the Study of Missing Persons at the University of Portsmouth, says: Missing persons cases within the UK are typically resolved within the first 48 hours, but British citizens who go missing abroad tend to take much longer to be found. Our analysis shows that only 17.4 percent of these people are discovered within the first two days. Furthermore, nearly a third of the sample remained missing for over a month."

The researchers examined 330 closed cases from nine UK forces, relating to data collected between 2017 and 2019. In total, 65 percent of those people who were reported missing abroad were either found by the UK police (41.8 percent), discovered by their family (11.9 percent) or returned by their own accord (11.6 percent). Non-UK police or authorities accounted for just 20 percent of all finds.

Dr Shalev-Greene says: "Nearly 42 percent of cases in this sample were resolved by the efforts of the UK police. This underlines the importance and effectiveness of UK police officers in making inquiries into these disappearances. It indicates that investigations abroad are resolved more quickly when UK police forces are involved at the earliest opportunity."

The report also showed that white middle aged men were the most likely group of British people to be reported missing abroad, and the majority of people who had disappeared were last seen at their home address.

Most people (66.8 percent) were last seen at their home or neighbourhood

The average and median age was 33, ranging between 0 and 89 years old. This is contrasts with with a UK missing population that is mostly children.

The majority (59.1 percent) of people who were reported missing abroad were male. 40.3 percent were female. The remainder (0.6 percent) were transgender.

The vast majority of missing people were identified as white (67.4 percent)

The study was funded by the International Crime Co-ordination Centre. It is thought to be amongst the first to break down missing abroad cases in such detail, enabling a range of trends, patterns and practices to be highlighted

Detective Inspector Helen Lomas, International Crime Co-ordination Centre says: "Until now there has been no research as to the numbers and types of international missing person investigations and this needs to be rectified. Police officers need to be aware of how many people go missing abroad and what the patterns of such disappearances are.

"This study explores these gaps, and the unique challenges faced by investigators tasked at solving these cases. This report examines these issues with a view to making immediate recommendations in the short term that can be taken forward to inform training, response and future research."

The study also shows the circumstances leading to a disappearance are different to those previously considered to be stereotypical cases, such as cases of getting lost, abduction or homicide. The results suggest that the majority of people are reported missing due to misunderstanding, miscommunication or lost documents - (20 percent) followed by lost contact (16.1 percent) and asylum seeker, refugee or migrant, including visiting family and travelling (13.2 percent).

A number of recommendations have been made, based on the findings of this study. They include; future training, consideration of the increased length of time UK police spend on these cases, the cost and burden of these cases and the challenges of working abroad. A central database that gathers and collates information on missing abroad cases is also recommended to promote understanding of these cases and to reduce ambiguity between forces.

With the voice commands "Alexa Skills," users can load numerous extra functions onto their Amazon voice assistant. However, these Skills can often have security gaps and data protection problems, as a team of researchers from the Horst Görtz Institute for IT Security at Ruhr-Universität Bochum (RUB) and North Carolina State University discovered, together with a former PhD student who started to work for Google during the project. They will present their work at the "Network and Distributed System Security Symposium (NDSS)" conference on 24 February 2021.

More than 90,000 Skills analyzed

In their study, the researchers around Christopher Lentzsch and Dr. Martin Degeling studied first-time the ecosystem of Alexa Skills. These voice commands are developed not only by the U.S. tech company Amazon itself but also by external providers. Users can download them at a store operated by Amazon directly, and in some cases, they are also activated automatically by Amazon.

The researchers obtained and analyzed 90,194 Skills from the stores in seven country platforms. They found significant deficiencies for safe use. "A first problem is that Amazon has partially activated Skills automatically since 2017. Previously, users had to agree to the use of each Skill. Now they hardly have an overview of where the answer Alexa gives them comes from and who programmed it in the first place," explains Dr. Martin Degeling from the RUB Chair of System Security. Unfortunately, it is often unclear which Skill is activated at what time. For example, if you ask Alexa for a compliment, you can get a response from 31 different providers, but it's not immediately clear which one is automatically selected. Data that is needed for the technical implementation of the commands can be unintentionally forwarded to external providers.

Publishing new Skills under a false identity

"Furthermore, we were able to prove that Skills can be published under a false identity. Well-known automotive companies, for example, make voice commands available for their smart systems. Users download these believing that the company itself has provided these Skills. But that is not always the case," says Martin Degeling. Although Amazon checks all Skills offered in a certification process, this so-called Skill squatting, i.e., the adoption of already existing provider names and functions, is often not noticeable.

"In an experiment, we were able to publish Skills in the name of a large company. Valuable information from users can be tapped here," explains the researcher. So if an automotive supplier has not yet developed a Skill for its smart system in the car to turn up or turn down the music in the car, for example, attackers would be able to do so under the supplier's name. "They can exploit users' trust in the well-known name and in Amazon to tap into personal information such as location data or user behaviour," Degeling says. Criminals, however, could not directly tap encrypted data or change commands with malicious intent in this process to manipulate the smart car, for example to open the car doors.

Circumventing Amazon's security check

The researchers also identified another security risk: "Our study also showed that the Skills could be changed by the providers afterward," explains Christopher Lentzsch from the RUB Chair of Information and Technology Management. This vulnerability places the security of the previous certification process on the part of Amazon into another perspective. "Attackers could reprogram their voice command after a while to ask for users' credit card data, for example," Lentzsch says. Amazon's testing usually catches such prompts and does not allow them - the trick of changing the program afterward can bypass this control. By trusting the abused provider name and Amazon, numerous users could be fooled by this trick.

Unsufficient data protection declarations

In addition to these security risks, the research team also identified significant lacks in the general data protection declarations for the Skills. For example, only 24.2 percent of the Skills have a so-called Privacy Policy at all, and even fewer in the particularly sensitive areas of "Kids" and "Health and Fitness." "Especially here, there should be strong improvements," Degeling says.

Amazon has confirmed some of the problems to the research team and says it is working on countermeasures.

ROCKVILLE, MD - The remarkable genetic scissors called CRISPR/Cas9, the discovery that won the 2020 Nobel Prize in Chemistry, sometimes cut in places that they are not designed to target. Though CRISPR has completely changed the pace of basic research by allowing scientists to quickly edit genetic sequences, it works so fast that it is hard for scientists to see what sometimes goes wrong and figure out how to improve it. Julene Madariaga Marcos, a Humboldt postdoctoral fellow, and colleagues in the lab of Professor Ralf Seidel at Leipzig University in Germany, found a way to analyze the ultra-fast movements of CRISPR enzymes, which will help researchers understand how they recognize their target sequences in hopes of improving the specificity. Madariaga Marcos will present the research on Tuesday, February 23 at the 65th Annual Meeting of the Biophysical Society.

To use CRISPR enzymes to edit gene sequences, scientists can tailor them to target a specific sequence within the three billion DNA base pairs in the human genome. During target recognition CRISPR enzymes untwist the DNA strands to find a sequence that is complementary to CRISPR's attached RNA sequence. But sometimes the RNA matches to DNA sequences that are not quite complementary. To troubleshoot this unintended match, scientists need to be able to observe how CRISPR is acting along individual DNA base pairs, but the process is fast and difficult to observe.

To measure CRISPR's actions on an ultra-fast timescale, Madariaga Marcos and colleagues turned to DNA origami, which uses special DNA sequences to form complex three-dimensional nanostructures instead of a simple double helix. DNA origami has applications in drug delivery, nanoelectronics, and even art. Using DNA origami, they built rotor arms out of DNA so that they could watch with a high-speed camera on a microscope the untwisting of the DNA by CRISPR enzymes, causing the rotor arm to spin like helicopter blades. With this system, they were able to measure the different responds to matches and mismatches within the DNA sequence. "We are able to directly measure the energy landscape of CRISPR/Cascade when it interacts with DNA for the first time," said Madariaga Marcos.

This technique will help scientists better understand CRISPR enzymes, and how they ultimately land on their match. That way, they can figure out how to optimize CRISPR so it makes fewer off-target matches. In the future, Madariaga Marcos is interested in "developing more tools and methods for studying these gene editing processes in new ways and at a more detailed level."

The use of the polymeric flame retardant PolyFR in "eco-friendly" foam plastic building insulation may be harmful to human health and the environment, according to a new commentary in Environmental Science & Technology. The authors' analysis identifies several points during the lifecycle of foam insulation that may expose workers, communities, and ecosystems to PolyFR and its potentially toxic breakdown products.

With the climate crisis fueling demand for energy-efficient insulation, the production of PolyFR is increasing rapidly. That's because this flame retardant is added to all foam plastic building insulation in North America to comply with flammability codes, replacing the flame retardant hexabromocyclododecane that has been globally phased out due to its toxicity and persistence. PolyFR is commonly assumed to be safe. However, the authors question that assumption.

The presumed safety of PolyFR hinges on the claim that as a large molecule called a polymer, it has few opportunities for release from foam insulation. But the authors' analysis shows that in fact, PolyFR in building insulation has significant opportunities for release into the environment during manufacturing, installation, and disposal of foam insulation. Once released, the PolyFR may break down into harmful chemicals that can end up in people and ecosystems.

"Since so much PolyFR is being used and so little is known about its release into the environment, we need to have realistic assessments of the potential for PolyFR across its life cycle to harm human and environmental health," said Miriam Diamond, Professor at University of Toronto and corresponding author of the study.

PolyFR is a polymer made from butadiene and styrene, which are both carcinogens. Bromine is added making it a brominated flame retardant--such flame retardants studied in the past were found to be toxic and many have been phased out of use.

A greater understanding of the potential for health harm associated with the increasing production of PolyFR, as well as its eventual breakdown and disposal, is needed to protect workers, fenceline communities near waste disposal sites, and others exposed throughout this flame retardant's lifecycle.

Importantly, alternative insulation materials already exist which do not require the use of potentially hazardous flame retardants. Inherently flame-resistant mineral fibers, such as glass wool or stone wool, can be used instead. Also, the fire safety benefit of adding flame retardants should be established before such chemicals are used.

"Making buildings more energy-efficient is a key part of tackling the climate crisis," said co-author Arlene Blum, Executive Director of the Green Science Policy Institute. "But we need to be careful not to create new health and environmental problems along the way. A 'green building' with potentially hazardous insulation isn't a green building at all."

In recent years, researchers have discovered ways to remove specific fears from the brain, increase one's own confidence, or even change people's preferences, by using a combination of artificial intelligence and brain scanning technology. Their technique could lead to new treatments for patients with conditions such as post-traumatic stress disorder (PTSD), phobias or anxiety disorders.

But while this technique is extremely promising, in some individuals it remains unsuccessful. Why are there such differences in outcome? Better understanding how the brain can self-regulate its own activity patterns would go a long way toward establishing the technique for clinical use. The researchers who spearheaded this technique have thus released a unique dataset (which includes five different studies) to the community, in a bid to accelerate the translation from basic science to application.

The technique is called 'Decoded Neurofeedback', and is based on a method to read and identify specific information in the brain - for example, a fear memory. Dr. Mitsuo Kawato, Director of the Computational Neuroscience Laboratories at the ATR Institute International in Japan, and senior author on the paper and who pioneered the technique a decade ago, explained: "In Decoded Neurofeedback experiments, brain scanning is used to monitor activity in the brain, and identify complex patterns of activity that resemble a specific memory or mental state. When the pattern is detected, we give our experimental participants a small reward. The simple action of repeatedly providing a reward every time the pattern is detected modifies the original memory or mental state. Importantly, participants do not need to be aware of the patterns' content for this to work."

Dr. Aurelio Cortese, senior researcher at ATR Institute International and lead author of the paper, explained the vision for releasing the data: "The Decoded Neurofeedback approach could have major benefits for clinical populations over traditional treatments. Patients could avoid the stress associated with exposure therapies, or side-effects resulting from established drugs. As such, it is crucial we accelerate the development of the Decoded Neurofeedback technique - and this will only be possible if more scientists will be able to work on the actual data."

Young novice drivers who speak into hand-held smartphones while driving are also likely to drive while under the influence of drink or drugs, according to researchers at Lero, the Science Foundation Ireland Research Centre for Software.

The study "Smartphone Use While Driving: An Investigation of Young Novice Driver (YND) Behaviour," also found that speaking on a hand-held phone is strongly correlated with high-risk driving behaviours such as overtaking on the inside of the car ahead, speeding, driving without a valid licence and driving while intoxicated.

Lero researchers, surveyed 700 German Young Novice Drivers (YNDs), with an average age of just over 21. While the data relates to Germany, it may point to young drivers' risky driving behaviour in other motorised countries, enabling road safety authorities to target information campaigns designed for younger drivers, the authors believe.

Dr Darren Shannon of Lero and University of Limerick said car crashes are the leading cause of death for those between the ages of 15-29, according to the World Health Organisation, with smartphone use acting as a significant contributory factor.

"The data also indicates a moderately-strong effect between talking on a hand-held phone and speeding more than 20 km/h over the speed limit in urban areas. Speeding in built-up areas is moderately correlated with reading notifications, sending texts, or voice messages.

"There is a strong association between those who speak on their phone and those who engage in risky activity with potentially fatal consequences, such as intoxicated driving, ignoring red traffic lights, and driving with more passengers than seatbelts," added Dr Shannon, a specialised vehicle collision researcher with the Emerging Risk Group (ERG), Kemmy Business School, UL.

Lero's Dr Martin Mullins said the work carried out by the team points to the prevalence of certain attitudes in young people who drive while using mobile phones. In Germany, for example, the research shows that a sizeable number of novice motorists deliberately disobey the law by hiding their phones while driving.

"These attitudes have implications for the safety of other road users. Our work allows for road safety authorities to accurately target information campaigns designed for younger drivers. Targeted campaigns should increase awareness that all smartphone-related activities can significantly increase the risk of a crash or near-crash event.

"We don't just see policymakers as responsible. Carmakers are making their cars seem like a place of entertainment. This may have induced a false perception that behaviours like changing the music while driving are perceived as safe, and should instead engage in efforts to reduce this type of behaviour," added Dr Mullins, Co-Leader of the ERG at UL.

Lero researcher and PhD student Tim Jannusch of Institute for Insurance Studies of TH Köln said that the overall high percentage of Young Novice Drivers using their phone for music-related activities may suggest that they might perceive music-related activities as less dangerous.

"This could be attributed to the fact that drivers are allowed to use the car stereo while driving, which implies that changing or searching for music is safe. Nevertheless, changing music while driving, like reading or writing text messages, can cause cognitive, visual and physical distraction and significantly increase the risk for road traffic collisions," said Mr Jannusch.

Dr Shannon said policymakers could use their results for public information policy development, and to tailor financial penalties for those engaging in smartphone behaviour linked to dangerous driving. "Our findings can also be used in a Usage-based Insurance (UBI) context to financially incentivise safer driving," he added.

A team of researchers designed and manufactured a new sodium-ion conductor for solid-state sodium-ion batteries that is stable when incorporated into higher-voltage oxide cathodes. This new solid electrolyte could dramatically improve the efficiency and lifespan of this class of batteries. A proof of concept battery built with the new material lasted over 1000 cycles while retaining 89.3% of its capacity--a performance unmatched by other solid-state sodium batteries to date.

Researchers detail their findings in the Feb. 23, 2021 issue of Nature Communications.

Solid state batteries hold the promise of safer, cheaper, and longer lasting batteries. Sodium-ion chemistries are particularly promising because sodium is low-cost and abundant, as opposed to the lithium required for lithium-ion batteries, which is mined at a high environmental cost. The goal is to build batteries that can be used in large-scale grid energy storage applications, especially to store power generated by renewable energy sources to mitigate peak demand.

"Industry wants batteries at cell-level to cost $30 to $50 per kWh," about one-third to one-fifth of what it costs today, said Shirley Meng, a professor of nanoengineering at the University of California San Diego, and one of the paper's corresponding authors. "We will not stop until we get there."

The work is a collaboration between researchers at UC San Diego and UC Santa Barbara, Stony Brook University, the TCG Center for Research and Education in Science and Technology in Kolkata, India, and Shell International Exploration, Inc.

For the battery described in the Nature Communications study, researchers led by UC San Diego nanoengineering professor Shyue Ping Ong ran a series of computational simulations powered by a machine learning model to screen which chemistry would have the right combination of properties for a solid state battery with an oxide cathode. Once a material was selected as a good candidate, Meng's research group experimentally fabricated, tested, and characterized it to determine its electrochemical properties.

By rapidly iterating between computations and experiments, the UC SanDiego team settled on a class of halide sodium conductors made up of sodium, yttrium, zirconium and chloride. The material, which they named NYZC, was both electrochemically stable and chemically compatible with the oxide cathodes used in higher voltage sodium-ion batteries. The team then reached out to researchers at UC Santa Barbara to study and understand the structural properties and behavior of this new material.

NYZC is based on Na3YCl6, a well-known material that is unfortunately a very poor sodium conductor. Ong suggested substituting zirconium for yttrium because it would create vacancies and increase the volume of the cell battery unit, two approaches that increase the conduction of sodium ions. Researchers also noted that, in conjunction with the increased volume, a combination of zirconium and chloride ions in this new material undergoes a rotating motion, resulting in more conduction pathways for the sodium ions. In addition to the increase in conductivity, the halide material is much more stable than materials currently used in solid-state sodium batteries.

"These findings highlight the immense potential of halide ion conductors for solid-state sodium-ion battery applications," said Ong. "Further, it also highlights the transformative impact that large-scale materials data computations coupled with machine learning can have on the materials discovery process."

Next steps include exploring other substitutions for these halide materials and increasing the battery's overall power density, along with working to scale up the manufacturing process.

Graphene, a two-dimensional material composed exclusively of carbon, has revealed extraordinary properties, including thermal and electrical conductivity, transparency, and flexibility. When combined, these properties become particularly interesting in the age of touch screens and flexible electronics! 'Unlike 3D materials, graphene has a height reduced to the ultimate dimension of the atom. It's therefore a carbon atom plane,' explains Prof. Jean-Christophe Charlier, a specialist in nanoscopic physics at the Institute of Condensed Matter and Nanosciences of UCLouvain.

In a study published in Nature, the scientist and his team dissected the behaviour of electrons when two layers of graphene superimposed at an angle of 1.1 degrees (the so-called 'magic angle') produce a moiré effect. Well known to photographers, painters and fashion specialists, this optical effect consists of a figure composed of dark and light domains resulting from the superposition of two gratings. 'When two layers of graphene are superimposed with this magic angle, they give rise to superconductivity. They therefore conduct electricity without any resistance,' Prof. Charlier says. This property is more than useful for transporting electricity without loss of energy. 'We've shown that the two graphene planes twisted in this way interact and lead to a restructuring of the atoms into domains where electrons are trapped and localised in space.' However, by definition, electrons tend to move away from one other, repelled by their respective negative charges. 'To limit their interactions, the electrons can organise themselves by aligning their spin, which gives them magnetic properties, or by forming an insulator, or by pairing up to produce superconductivity.' It's the last that occurs in the case of bilayer graphene twisted at the magic angle. In addition, the scientists have shown that phonons, atom particles responsible for vibrations in solid materials, are also trapped in the domains formed by the twisted graphene.

The synthesis of new 2D materials and the observation of the extraordinary properties which can be derived from them have led to a twistronics craze driven by the idea of one day being able to create structures with the desired properties 'brick by brick', or to extrapolate knowledge acquired on simple materials, such as graphene, to more complex materials, allowing for better control or performance of superconducting systems in everyday life. Examples include the superconducting coils in Japanese magnetic levitation trains (Maglev), which levitate above the rails, or the superconducting magnet in magnetic resonance imaging (MRI) equipment.

Its muscular body shape and large pectoral fins are perfect for long-distance travel, yet movement patterns of the whitespotted eagle ray (Aetobatus narinari) remain a mystery. Researchers from Florida Atlantic University's Harbor Branch Oceanographic Institute in collaboration with Mote Marine Laboratory & Aquarium, the University of Florida and the Florida Fish and Wildlife Conservation Commission, are the first to conduct a multiyear study examining large-scale movements of whitespotted eagle rays in United States waters.

Between 2016 and 2018, scientists fitted 54 rays with acoustic transmitters and tracked them using collaborative acoustic telemetry networks. The rays were tagged along both the Gulf of Mexico and Atlantic coasts of Florida, which differ in environmental characteristics. Scientists compared rays' movement patterns between the Atlantic and Gulf coasts and gathered data on migratory routes, seasonality and habitat use. Their findings suggest that potential sub-population structuring may be occurring within Florida more than previously thought and have significant conservation and adaptive management implications for this protected species.

Results of the study, published in the journal Marine Biology, reveal striking differences in travel patterns on the Atlantic coast compared to the Gulf coast. The majority of Gulf coast whitespotted eagle rays preferred to "spread their wings," exhibiting migratory and transient behaviors, while most Atlantic coast tagged rays were "homebodies" and remained a resident within the Indian River Lagoon. Atlantic coast rays spent greater than five times the amount of time inshore, regardless of maturity or sex, than Gulf coast rays.

"Although tagged at similar latitudes, whitespotted eagle rays exhibited coastline-specific movements. The rays on the Gulf coast conduct repetitive annual migration patterns, heading south from Sarasota starting in fall and returning to the area in early spring," said Breanna DeGroot, M.S., first author and research coordinator, FAU Harbor Branch.

DeGroot worked on the study with co-author Matt Ajemian, Ph.D., principal investigator, an assistant research professor at FAU Harbor Branch and head of the Fisheries Ecology and Conservation (FEC) Lab, who supervised the study.

"This behavior is likely driven by a combination of environmental factors, but most notably temperature. In addition, the expansive, shallow shelf on the Gulf coast may provide additional habitat, enabling rays to move over larger distances along nearshore migratory corridors and lessen their reliance on inshore estuaries," said Ajemian.

On both coastlines, water temperatures during times when rays were present were significantly warmer (at least 27.8 degrees Celsius) compared to temperatures when rays were absent (below 24.9 degrees Celsius), suggesting it may be a major abiotic factor influencing migration patterns. Ontogenetic shifts in habitat use were evident along the Atlantic coast in the Indian River Lagoon, but not along the Gulf coast. Immature rays spent significantly more time (about 91.5 percent) inside the Indian River Lagoon compared to mature counterparts (about 60.2 percent).

"Most of the rays we tagged on Florida's Atlantic coast resided in the same area where they were originally tagged, which increases their susceptibility to local stressors like persistent environmental impacts in the Indian River Lagoon," said DeGroot. "Moreover, immature rays spent a significantly larger proportion of time inside the confines of the lagoon. This is especially disconcerting because we found no evidence of neonate or young-of-the-year rays leaving the lagoon throughout the entire three-year study."

The consistent presence of rays in the Indian River Lagoon throughout the study suggests that it serves as parturition grounds and nursery habitat for rays. As males and females were equally resident to the Sebastian portion of the Indian River Lagoon, this area is likely an important feeding ground, nursery habitat, mating location, pupping ground, or serves a combination of these roles.

"This information about year-round or seasonal residency and longer distance migrations would not be possible without the collaborative data sharing of the acoustic telemetry networks such as iTAG and the FACT Network," said Kim Bassos-Hull, M.Sc., co-author and senior biologist with Mote Marine Lab's Sharks & Rays Conservation Research Program.

According to Ajemian, there is a need for a better understanding of how extreme weather events such as hurricanes and fluctuations in environmental factors such as red tide and harmful algal blooms may impact ecologically important large-bodied mesopredators like the whitespotted eagle ray, because the frequency of these events is predicted to increase yet the potential alterations on the ecosystem remain unknown.

"This is a critical issue that requires increased tracking infrastructure and new analytical approaches," said Susan Lowerre-Barbieri, Ph.D., co-author, University of Florida and Florida Fish and Wildlife Conservation Commission, who led an iTAG workshop on this topic.

Study co-authors are Krystan A. Wilkinson, Ph.D., Mote Marine Lab's Sharks & Rays Conservation Research Program and the Chicago Zoological Society's Sarasota Dolphin Research Program; and Gregg R. Poulakis, Ph.D., Florida Fish and Wildlife Conservation Commission.

"I'm looking forward to adding more pieces to the eagle ray puzzle in the coming years as these animals get detected for years to come along both coasts of the state and beyond," said Poulakis.

According to recent estimates, there will be roughly 10 billion people to feed in 2050. Agricultural production will need to increase by almost 56% to guarantee food security globally, without converting more land for agriculture (in line with environmental and climate targets). This unprecedented challenge has ushered in the era of "smart agriculture," which promises to revolutionize food production by combining agricultural techniques with information technology, automation, and artificial intelligence. This new era, called "Agriculture 4.0," could ensure sustainable food production for the entire world. However, as communities gradually embrace smart agriculture, it is important to understand how to manage the security and privacy risks associated with the integration of information technology into agriculture.

To this end, in a new survey published in IEEE/CAA Journal of Automatica Sinica, researchers from China, Algeria, and the UK have performed a comprehensive analysis of the risks involved in current technologies used in smart agriculture and identified potential countermeasures. Lei Shu, a Professor from Nanjing Agricultural University in China and University of Lincoln in UK, the leading author of the paper, and Xing Yang from Nanjing Agricultural University in China, the first author of the paper, say, "Smart agriculture provides solutions for agricultural intelligence and automation. Both intellectual and unmanned operations are the development goals of smart agriculture."

The researchers also state that the field of smart agriculture is ripe with the risks of information theft and cyberattacks. To prevent these risks from putting global food supply in jeopardy, Yang and his team identified and proposed adequate countermeasures to the risks, based on the context (or "mode") of agricultural production. Commenting on their approach, Yang explains, "Security countermeasures based on urban conditions may not be suitable for rural conditions." They categorized the agricultural system into three modes: precision agriculture, facility agriculture, and order agriculture. Each of these modes has its own distinctive features (scale, climate, infrastructure, equipment, and technology) that makes it vulnerable to distinct types of risks requiring equally distinct countermeasures.

After laying this groundwork, the researchers set out to analyze the various security challenges involved in the three modes. First, they identified key technologies involved in each mode and their applications. The Internet of Things (IoT), which is arguably the most important technology in smart agriculture, is used in every mode, but has different applications depending on what specific tasks need to be performed. For instance, it is used in field agriculture to record environmental variables and analyze trends to predict optimal fertilizer input, while it can be used to automate environmental conditions in greenhouses and aquaculture. In each case, the way in which the technological architecture is set up exposes it to widely varying types of security challenges. For example, extreme environmental conditions can damage sensing equipment outside, while unauthorized access and malicious cyberattacks can compromise data integrity and site security, tamper with automated equipment, and lead to severe financial costs and a loss in food production. To better assess the solutions needed in each case, the researchers classified the challenges they identified as belonging either to agricultural production or information technology.

Reviewing each technology and their current applications, the researchers proposed six general countermeasures. These include technological solutions such as intrusion detection systems, authentication and access control, and privacy-preserving, blockchain-based solutions for data integrity, as well as physical countermeasures. Their study goes into great detail about how each solution can be applied in different contexts and how they address each of the challenges identified for smart agriculture.

After this comprehensive review, the scientists went one step further and pointed out that little is known about the potential security risks for agricultural equipment, such as sensors and tractors. They portray this lack of knowledge using a case study of one piece of equipment: a solar insecticidal lamp based on an IoT architecture (SIL-IoT). Their experiments showed that this lamp can cause electromagnetic interference and might even cause wireless sensor networks to malfunction. In this case, a simple physical separation distance was enough to address the security risk; however, the researchers advise caution.

As agriculture becomes more technologically complex, so will the challenges of ensuring its security. To this end, the researchers discussed other emerging technologies (such as 5G networks and VR/AR simulation) and the need for further research on their security impacts as their integration in smart agriculture becomes inevitable in the near future.

As we move towards a sustainable future with smart agriculture, let's also learn take a step back from time to time to check how we could become truly smart about it.

Researchers of the University of Helsinki have resolved for the first time, how the ultrafine particles of atmosphere effect on the climate and health.

Atmospheric air pollution kills more than 10,000 people every day. The biggest threat to human health has been assumed to be the mass accumulation of atmospheric particles with diameter smaller 2.5 μm: the higher the mass and loss of visibility, the bigger the threat.

The researchers of the Institute for Atmospheric and Earth System Research (INAR) at the University of Helsinki together with collaborators in China discovered that if we want to solve the accumulation of the biggest particles, we need to start with the smallest.

Until recent studies, very little attention had been given to the ultrafine particles, smaller than 100 nm in diameter, since their weight and surface area are comparably negligible. It has been controversial whether these particles can grow to relevant sizes where they can affect visibility and human health.

"We found that the smallest particles matter the most", says Academician Markku Kulmala from the Institute for Atmospheric and Earth System Research (INAR).

The results of two studies were recently published in Faraday Discussion and Nature NPJ climate and atmospheric science.

Sur­vival to mass rel­ev­ant sizes

When there are enough precursor vapors available and when the conditions are favorable, particles forming in the atmosphere through gas-to-particle conversion at ~1 nm in diameter appear abruptly in the air. This atmospheric phenomenon known as New Particle Formation is observed in many different environments around the world.

"We are speaking of hundred thousands of particles per cubic centimeter especially in Megacities where increased population meets increased pollution", says Lubna Dada from the Institute for Atmospheric and Earth System Research (INAR).

The researchers tackled the for-long controversial topic whether these smallest particles have an effect on haze formation, visibility and air pollution. In two parallel studies, they deployed the most up-to-date state-of-the-art instrumentation in the center of Beijing to tackle 'haze'.

In the first study, they followed the growth and chemical composition of the freshly formed particles from sizes ~ 1 nm until those reached sizes where they contribute to mass accumulation, in an attempt to understand the reasons behind their formation and survival to mass relevant sizes.

In the second study, the researchers deployed sophisticated instrumentation at ground level and at a 260 m and estimated the contribution of ground base sources to haze formation and accumulation.

Also the smal­lest matter

The results showed that In Megacities, Beijing in this case, the smallest particles are formed from gaseous sulfuric acid and ammonia or amines, which are ubiquitous. The particles grow via condensation of organics and nitrate which are equally available throughout the city.

While traffic and other anthropogenic activities do contribute to haze formation, new particle formation and growth are equally important.

In order to alleviate the air pollution problem and to reduce haze, the researchers suggest an increased attention towards the very small particles and vapors.

"It´s crucial to control the precursor vapors needed to form the particles and the vapors needed to grow them", Dada says.

A bubble pre­vent­ing di­lu­tion

It was also found in the studies that new particle formation is a regional phenomenon happening over 100 of kilometers, while its amplification and growth to haze relevant sizes is rather local. The increased pollution on ground level together with amplified urbanization like high buildings create something like a bubble which separates the city from the upper atmosphere.

The more pollution is trapped in this bubble, the more stable it makes it, preventing the pollutants from being diluted into the upper atmosphere and concentrating pollution inside the city where people live. It is a runaway effect, the more pollutants are emitted the more trapping happens, making haze even worse at ground level.

"In brief, it is not only the particles that are directly emitted by anthropogenic activities such as traffic and industry need to be controlled, but also the associated vapors which are capable of forming seed particles on their own or grow those that are already present. To solve the big, we need to start small," Dada summarizes.

Having a memory of past events enables us to take smarter decisions about the future. Researchers at the Max-Planck Institute for Dynamics and Self-Organization (MPI-DS) and the Technical University of Munich (TUM) have now identified how the slime mold Physarum polycephalum saves memories - although it has no nervous system.

The ability to store and recover information gives an organism a clear advantage when searching for food or avoiding harmful environments. Traditionally it has been attributed to organisms that have a nervous system.

A new study authored by Mirna Kramar (MPI-DS) and Prof. Karen Alim (TUM and MPI-DS) challenges this view by uncovering the surprising abilities of a highly dynamic, single-celled organism to store and retrieve information about its environment.

Window into the past

The slime mold Physarum polycephalum has been puzzling researchers for many decades. Existing at the crossroads between the kingdoms of animals, plants and fungi, this unique organism provides insight into the early evolutionary history of eukaryotes - to which also humans belong.

Its body is a giant single cell made up of interconnected tubes that form intricate networks. This single amoeba-like cell may stretch several centimeters or even meters, featuring as the largest cell on earth in the Guinness Book of World Records.

Decision making on the most basic levels of life

The striking abilities of the slime mold to solve complex problems, such as finding the shortest path through a maze, earned it the attribute "intelligent". It intrigued the research community and kindled questions about decision making on the most basic levels of life.

The decision-making ability of Physarum is especially fascinating given that its tubular network constantly undergoes fast reorganization - growing and disintegrating its tubes - while completely lacking an organizing center.

The researchers discovered that the organism weaves memories of food encounters directly into the architecture of the network-like body and uses the stored information when making future decisions.

The network architecture as a memory of the past

"It is very exciting when a project develops from a simple experimental observation", says Karen Alim, head of the Biological Physics and Morphogenesis group at the MPI-DS and professor on Theory of Biological Networks at the Technical University of Munich.

When the researchers followed the migration and feeding process of the organism and observed a distinct imprint of a food source on the pattern of thicker and thinner tubes of the network long after feeding.

"Given P. polycephalum's highly dynamic network reorganization, the persistence of this imprint sparked the idea that the network architecture itself could serve as memory of the past", says Karen Alim. However, they first needed to explain the mechanism behind the imprint formation.

Decisions are guided by memories

For this purpose the researchers combined microscopic observations of the adaption of the tubular network with theoretical modeling. An encounter with food triggers the release of a chemical that travels from the location where food was found throughout the organism and softens the tubes in the network, making the whole organism reorient its migration towards the food.

"The gradual softening is where the existing imprints of previous food sources come into play and where information is stored and retrieved", says first author Mirna Kramar. "Past feeding events are embedded in the hierarchy of tube diameters, specifically in the arrangement of thick and thin tubes in the network."

"For the softening chemical that is now transported, the thick tubes in the network act as highways in traffic networks, enabling quick transport across the whole organism", adds Mirna Kramar. "Previous encounters imprinted in the network architecture thus weigh into the decision about the future direction of migration."

Design based on universal principles

"Given the simplicity of this living network, the ability of Physarum to form memories is intriguing. It is remarkable that the organism relies on such a simple mechanism and yet controls it in such a fine-tuned manner," says Karen Alim.

"These results present an important piece of the puzzle in understanding the behavior of this ancient organism and at the same time points to universal principles underlying behavior. We envision potential applications of our findings in designing smart materials and building soft robots that navigate through complex environments", concludes Karen Alim.

During this unique study, a team of researchers led by Professor Jane Ogden from the University of Surrey investigated the impact of actively preparing or watching others prepare food (e.g., on a cooking show) versus distraction away from this focus. Researchers sought to understand how this may affect the amount of food consumed and influence the desire to continue eating.

To investigate this further, eighty female participants were recruited and assigned to one of four groups: active food preparation (preparing a cheese wrap within 10 minutes), video food preparation (watching a video of a researcher preparing a cheese wrap), distraction (undertaking a 10-minute colouring task) and a control group. All groups were then requested to eat the wrap.

Researchers measured how much of the wrap each participant ate and assessed their desire to continue eating (questions included 'I could eat now,' 'I do not want to eat' and 'I am thinking about food'). It was found that those who had either actively prepared the wrap or watched someone else do so consumed more and reported a greater desire to eat than those in the distraction group.

Jane Ogden, Professor of Health Psychology at the University of Surrey, said: "We found that actively preparing food yourself or watching someone else prepare food can lead to increased feelings of hunger and to eating more.

"The impact of this depends on the kinds of food being prepared. If the food is lacking in nutritional value this could lead to weight gain and unhealthy overeating. However, if people are preparing their own nutritious food or watching others do the same then this could actually be a good influence, particularly if they are cooking with children as it could encourage them to eat more of the healthier foods that they may not have usually wanted to eat."