Tech

Recently, Prof. XIE Can from the High Magnetic Field Laboratory of the Hefei Institutes of Physical Science (HFIPS), in a collaboration with Prof. YAN Xiyun's lab from the Institute of Biophysics, reported the structural basis of mAb AA98's inhibition on CD146-mediated endothelial cells (EC) activation and designed higher affinity monoclonal antibody HA98 for cancer treatment.

CD146 is an adhesion molecule that plays important roles in angiogenesis, cancer metastasis, and immune response. Prof. YAN Xiyun's lab has been focused on the function of CD146 and the mechanism underlain, aiming to develop antibody drugs targeting CD146. Their previous studies demonstrated that CD146 triggered the signaling cascade via dimerization induced by various ligands. AA98, a monoclonal antibody (mAb) binding to CD146, shows inhibitory effects on tumor growth. However, the structural basis of CD146 activation and AA98 inhibition remains to be addressed.

In this research, the researchers described a crystal structure of the CD146/AA98 Fab complex at a resolution of 2.8 angstrom. Structural analysis elucidated AA98 stabilized CD146 in monomer conformation thus inhibited EC activation. A higher-affinity AA98 variant (named HA98) was then rationally designed based on the complex structure in this study.

Further experiments on animal model with HA98 revealed superior inhibitory effects on tumor growth to those of AA98, which suggested future applications of this antibody in cancer therapy.

"There was so much to do," said XIE, "this collaborative project was initiated about 9 years ago. The crystal structure of CD146/AA98 complex was only the first step, and how to use the structural information we obtained in rational design was much more attractive to us. Researchers from two labs have been working together from different perspectives to bring up a better antibody for potential cancer therapy. The collaboration was successful indeed."

Dispersal is an important process governing the persistence of wild animal populations. Upon reaching sexual maturity, individuals usually disperse from their natal home range to search for suitable habitat and mates for reproduction. As such, dispersal promotes gene flow among populations, allows rescuing small and isolated populations, and enables the colonization of unoccupied habitats. In human-dominated landscapes, however, dispersing animals find it increasingly difficult to cross densely populated areas that separate suitable habitats. For this reason, the identification and preservation of wildlife corridors has become of utmost importance for conservation authorities worldwide.

In southern Africa, the governments of Angola, Botswana, Namibia, Zambia and Zimbabwe have agreed to preserve an unprecedented network of wildlife corridors, connecting up to 35 already-existing national parks, game reserves and other protected areas. The Kavango-Zambezi Conservation Area (KAZA) spans roughly 520,000 square kilometers, making it the world's largest terrestrial conservation area. But do the boundaries of the KAZA match the dispersal behavior of the species it seeks to protect? Researchers at the University of Zurich sought to answer this question by studying the African wild dog (Lycaon pictus), the most endangered and most mobile species in the KAZA.

Critically endangered large predator

African wild dogs currently number around 6,000 free-ranging individuals acrossa few remaining populations in southern and eastern Africa. Wild dogs live in packs of up to 30 individuals that are led by one dominant couple. After reaching sexual maturity, wild dogs disperse in an attempt to find potential mates and suitable territory to settle. Similar to wolves, wild dogs can cover hundreds of kilometers during this journey.

"We wanted to find out how and where dispersing wild dogs move and investigate whether the different populations within the Kavango-Zambezi Conservation Area are able to connect with each other," says David Hofmann, first author of the study and PhD student at the Department of Evolutionary Biology and Environmental Studies. For this purpose, the UZH research team put GPS collars on several wild dogs and used the tracking data to find out which habitats dispersers prefer to cross and ultimately to predict which areas contain suitable wildlife corridors.

Very few corridors outside the conservation area

The results suggest that most of the identified wildlife corridors are located within the KAZA, with northern Botswana appearing to act as a central hub for dispersing individuals. Another important corridor connects national parks in Angola and Zambia. "While the corridor still runs through areas that are largely unprotected, the KAZA initiative does intend to place these zones under protection," says Hofmann. "There's still potential for expansion though as several suitable dispersal routes remain currently uncovered by the KAZA."

Not all areas are equally suitable for establishing wildlife corridors. In some countries, dispersers encounter little obstacles during dispersal, whereas in countries such as Zambia and Zimbabwe, high population densities and associated activities hinder animal movements. The researchers have thus urged that these country-specific differences have to be taken into consideration when implementing the KAZA initiative.

Lions and elephants also stand to benefit

The statistical methods and movement data employed in this study will not only be of use to decision-makers involved with the KAZA initiative, but can also be used to create new protected areas or to modify existing zones. The researchers' findings emphasize that the Kavango-Zambezi Transfrontier Conservation Area largely meets the needs of dispersing African wild dogs, thereby making an important contribution to conserving this endangered species in southern Africa. "Ultimately, expanding the network of wildlife corridors doesn't just help African wild dogs. Other species that live in the same ecosystem such as lions, elephants and cheetahs are also likely to benefit," says Hofmann.

Inclusion of soybean and linseed oils in the diet of dairy cows made the fatty acid content of their milk even healthier for human nutrition. It also increased the proportions of omega-6 and omega-3, which in the right balance play a key role in preventing cardiovascular diseases, for example, as well as chronic inflammation and some kinds of cancer.

Cardiovascular diseases are one of the world’s main public health problems. In Brazil, they are among the foremost causes of death. Each year some 300,000 Brazilians have heart attacks, dying in 30% of cases, according to the Health Ministry.

Research led by Arlindo Saran Netto, a professor at the University of São Paulo’s School of Animal Science and Food Engineering (FZEA-USP) in Pirassununga, São Paulo state, shows that consumption of these oils by dairy cows reduced the level of saturated fatty acids in their milk and increased the level of unsaturated fatty acids, which help reduce LDL, known as “bad cholesterol”.

An article published in PLOS ONE, reports the results of the research, which was supported by FAPESP. The study was one of a series led by Saran Netto for more than five years with the aim of improving food quality and developing novel types of milk and meat.

“The quality of the milk available on the market is good. In our research, we aim to create more opportunities to make sure milk benefits human health in novel ways. Many consumers want to go on a specific diet,” Saran Netto told Agência FAPESP.

The study showed that supplementing the cows’ feed with these two oils resulted in an omega-6/omega-3 ratio of 2.7:1 in their milk. Given the opposing effects of the two fatty acids, a healthy diet should be properly balanced. The World Health Organization (WHO) recommends between 5:1 and 10:1, but 50:1 could result from a diet consisting mostly of ultra-processed food with little fish and vegetables, causing an imbalance and heightening the risk of heart disease and cancer.

Like other mammals, humans cannot synthesize omega-6 or omega-3 and must obtain them from food. “Future studies should evaluate the health benefits of omega-enriched milk in the human diet,” the article concludes.

In the human metabolism, omega-6 and omega-3 compete for the same elongase and desaturase enzymes. Higher levels of omega-6 impair the metabolization of omega-3. Too much omega-6 can raise blood pressure and triglyceride levels, among other problems. Omega-3 can exert anti-inflammatory action and reduce blood lipids. Recent research has shown that diets with the right amounts of both play an important role in disease prevention.

Method

The researchers worked with 18 lactating Holstein dairy cows for 94 days. All animals were fed the same diet for the first ten days, followed by three experimental periods of 28 days. Control was a regular dairy cow diet with no addition of oil. Then soybean oil was added at 2.5% as a source of omega-6, followed by 2.5% linseed oil as a source of omega-3. Both oils corresponded to 2.5% of total dry matter, replacing corn. These levels were chosen because in previous studies by the group they enhanced the fatty acid profile of the milk without significantly altering yield. Milk samples were then analyzed for fat, protein, lactose, and total solids.

Research by Saran Netto’s group published in 2016 showed that the addition of canola oil to the diet of dairy cows also altered the fatty acid profile of their milk, making it healthier (read more at: agencia.fapesp.br/23371/).

Another study, also funded by FAPESP, experimented with supplementation comprising sunflower oil, organic selenium and vitamin E, improving animal health and both milk yield and conservation while showing that children who consumed the milk had increased levels of selenium and vitamin E in their blood.

Demand

Cow’s milk has historically been an important source of nutrients for human consumption. It is rich in proteins, calcium, magnesium, selenium and vitamin B12, among others. In recent decades, however, demand has fallen, especially in the United States and Canada, for several reasons including health and dietary concerns. For example, the fat in milk can cause allergic reactions and normally contains saturated fatty acids associated with weight gain and obesity. A great deal of scientific research has therefore been devoted to the adaptations needed to meet consumer demand for a healthier product.

Brazil ranks fifth among the world’s leading milk producers, with an annual output of 34 billion liters. Dairy is one of the most important segments of its food industry. Annual consumption of milk averages 170 liters per capita, less than the developed-country average (250-300 liters). UHT (long life) milk is the most consumed milk product, but sales of cheese have risen strongly in recent years.

The types of milk obtained by Saran Netto and his group are not yet on sale in Brazil, although the research is more than complete. The main reason, he said, is logistical difficulties with distribution and industrial processing that have delayed commercialization.

“In many cases, the same truck collects milk from several farms. This hinders development of the product because we can’t mix regular milk and milk produced by cows with a specific diet. Likewise in industry: we need a separate production line for special milk,” he said. “Consumer demand isn’t large enough yet to guarantee sales volumes that would make separate processing viable.” In future, he hopes to try to commercialize milk with supplemental omega-3 and antioxidants.

The article “Inclusion of soybean and linseed oils in the diet of lactating dairy cows makes the milk’s fatty acid profile nutritionally healthier for the human diet” is at: journals.plos.org/plosone/article?id=10.1371/journal.pone.0246357.

Journal

PLoS ONE

DOI

10.1371/journal.pone.0246357

Narrow-gap semiconductors with the ability to use visible light have garnered significant interest thanks to their versatility. Now, scientists in Japan have developed and characterized a new semiconductor material for application in process components stimulated by light. The findings have, for the first time, suggested a new way to reduce the band gap in cheaper and non-toxic tin-based oxide semiconductors for efficient light-based applications.

Semiconductors that can exploit the omnipresent visible spectrum of light for different technological applications would serve as a boon to the material world. However, such semiconductors often do not come cheap and can often be toxic. Now, a group of material scientists from Tokyo Institute of Technology and Kyushu University have collaborated to develop a cheaper and non-toxic narrow-gap semiconductor material with potential 'light-based' or photofunctional applications, according to a recent study published in Chemistry of Materials.

Tin-containing oxide semiconductors are cheaper than most semiconductor materials, but their photofunctional applications are constrained by a wide optical band gap. The aforementioned team of scientists, led by Dr. Kazuhiko Maeda, Associate Professor at the Department of Chemistry, Tokyo Institute of Technology, developed a perovskite-based semiconductor material that is free of toxic lead and can absorb a wide range of visible light (Figure 1). The team "doped," or intentionally introduced, hydride ions into the tin-containing semiconductor material. In doing so, they successfully reduced the band gap from 4 eV to 2 eV, due to the chemical reduction of the tin component that accompanied the hydride ion doping.

The scientists were also able to pinpoint a crucial tin reduction reaction in the semiconductor material through physicochemical measurements. This reduction leads to the generation of a "tin lone electron pair," whose different electronic states notably contribute to the visible light absorption of the material. They also attribute this desired property to the prior introduction of oxygen defects into the material. Highlighting the importance of the oxygen defects, Dr. Maeda, who is also a corresponding author of the study, explains, "The prior introduction of oxygen defects into BaSnO3 by Y3+ substitution for Sn4+ is also indispensable to realize a significant reduction of the band gap."

To confirm that the developed semiconductor material is indeed photofunctional, the scientists tested the applicability of the semiconductor material in a photoelectrode. They observed that the developed material gave a clear anodic photoresponse up to the expected 600 nm.

Speaking about the impact of the study, Dr. Katsuro Hayashi, Professor of the Faculty of Engineering, Kyushu University, and the other corresponding author of the study, says, "Overall, the study has enabled a giant leap in the development of a cheaper, non-toxic, narrow optical band gap, tin-containing semiconductor material for practical applications in solar cells, photocatalysis and pigments."

Thanks to the efforts of the researchers, we can expect significant advancements in the development of several more novel lead-free visible-light absorbing materials with myriad applications.

A new experiment shows that the more energy consumed by a clock, the more accurate its timekeeping.

Clocks pervade every aspect of life, from the atomic clocks that underlie satellite navigation to the cellular clocks inside our bodies. All of them consume energy and release heat. A kitchen clock, for example, does this by using up its battery. Generally the most accurate clocks require the most energy, which hints at a fundamental connection between energy consumption and accuracy. This is what an international team of scientists from Lancaster, Oxford, and Vienna set out to test.

To do this, they built a particularly simple clock, consisting of a vibrating ultra-thin membrane, tens of nanometers thick and 1.5 millimeters long, incorporated into an electronic circuit. Each oscillation of the membrane generated one electrical tick. The ingenious aspect of this design is that it is powered simply by heating the membrane, while the complete flow of energy through the clock can be measured electrically.

The scientists found that the more heat they supplied, the more accurately the clock ran. In fact, the accuracy was directly proportional to the heat released. To make the clock twice as accurate, they needed to supply twice as much heat.

The experimental team consisted of Dr Edward Laird at Lancaster University, Professor Marcus Huber at Atominstitut, TUWien, Dr Paul Erker and Dr Yelena Guryanova at the Institute for Quantum Optics and Quantum Information (IQOQI), and Dr Natalia Ares, Dr Anna Pearson and Professor Andrew Briggs from Oxford.

Their study, published in Physical Review X, is the first time that a measurement has been made of the entropy - or heat loss - generated by a minimal clock.

Understanding the thermodynamic cost involved in timekeeping is a central step along the way in the development of future technologies, and understanding and testing thermodynamics as systems approach the quantum realm.

It also shows a similarity between the operation of a clock and a steam engine. With a steam engine there is fundamental constraint on how much heat we must supply to do a desired amount of work. This constraint is the famous Second Law of Thermodynamics which is central to modern engineering. What this experiment suggests is that clocks, like engines, are constrained by the Second Law, with their output being accurate ticks instead of mechanical work.

Dr Edward Laird of Lancaster University said: "The subject of thermodynamics, which incorporates the most fundamental principles of nature, tells us that there are two types of machine that we cannot operate without releasing heat. One is the mechanical engine, which releases heat to do work, and the other is the computer memory, which releases heat when it rewrites itself. This experiment - in conjunction with other work - suggests that clocks are also limited by thermodynamics. It also poses an intriguing question: are all possible clocks limited in this way, or is it just a property of the ones we have studied?"

Interestingly, many everyday clocks have an efficiency that is close to what the scientists' analysis predicts. For example, their formula predicts that a wristwatch whose accuracy per tick is one part in ten million must consume at least a microwatt of power. In fact, a basic wristwatch usually consumes only a few times this amount. The laws of thermodynamics, discovered in the nineteenth century, are still finding new applications today.

A research team from the Skoltech Center for Design, Manufacturing and Materials (CDMM) studied the effects of processing additives - aluminum hydroxide and zinc stearate - on the polymerization kinetics of thermosets used in pultrusion. The research was published in the Journal of Composite Materials.

Fiber-reinforced plastic (FRP) structural elements that have obvious advantages over conventional materials, such as steel, wood, and concrete, are widely used in civil, marine and road construction. FRP structures are manufactured using the pultrusion process, in which polymerization is achieved by continuously pulling the material. Engineers extensively use mathematical models to optimize the pultrusion process and thereby avoid costly experiments often performed by trial and error.

To optimize the pultrusion process, one should carefully consider many parameters that determine the quality of the final product, and composition of the polymer mixture is one of them. Accurate description of pultrusion requires an appropriate model of resin cure kinetics, depending on the processing additive used. If properly chosen, the model helps determine the highest possible pulling speed. In turn, maximizing the pulling speed while maintaining the quality of the resulting profiles is essential for enhancing the efficiency and, therefore, the cost effectiveness of the pultrusion process.

A CDMM team, including PhD student Alexander Vedernikov and MSc student Yaroslav Nasonov led by associate professor Alexander Safonov and CDMM director, professor Iskander Akhatov, proved that additives have a considerable impact on the speed of polymerization in pultrusion. The team found that the pulling speed predictions differed by as much as 1.7 times for compositions with and without additives, which had a dramatic effect on the pultrusion performance.

"Our Laboratory of Composite Materials and Structures is intensively working on process optimization in order to increase profitability while maintaining the required quality of composite structures. To do this, we apply mathematical models of manufacturing processes and validate them in experiments on industrial equipment," Alexander Safonov explains.

The Korea Institute of Civil Engineering and Building Technology (KICT) has announced the development of a fully-automated peak-picking method for cable monitoring. The developed method will improve reliability of the method. Such as Incheon Bridge in South Korea, Cable-stayed bridges have received significant attention as efficient structural systems worldwide. In this regard, newly developed cable monitoring systems have become an essential and efficient maintenance approach for cable-stayed bridges. As structural integrity for stay-cables, tension force and damping ratio have been widely utilized as efficient metrics.

A research team in KICT, led by Dr. Seung-Seop Jin, has developed a fully-automated peak-picking method to extract the modal frequencies reliably and flexibly without any prior setting and human manipulation. The developed method utilizes the domain knowledge based on the physical characteristics of the stay-cables. It can be applied to any stay-cables irrespective of their physical characteristics. Consequently, it is fully-automated to estimate tension forces and damping ratio of any stay-cables.

For many years, vibration method has been widely adopted as a cost-effective method to monitor the stay-cables, since it does not require complicated device installation and its calibration. Since the vibration method simply installs the accelerometers in stay-cables, this method can apply to any stay-cables regardless of being in-service or built-in. Once the vibrational signal is measured by the accelerometer, this signal in time-domain is transformed into the Power Spectrum Density (PSD) in frequency domain. To estimate the tension force and damping ratio using vibration method, the modal frequencies (peaks in PSDs) are extracted via a peak-picking method.

Traditionally, a human manually performed peak-picking to select the modal frequencies. However, this method is vulnerable to operator's bias, mistake and fatigue. In other words, human error occurs. As a result, it makes the manual peak-picking challenging for real-time and long-term monitoring. Several methods for automated peak-picking are implemented by selecting peaks larger than a predefined threshold values from the PSD, local maxima point a PSD within pre-defined frequency intervals, and peaks detected by deep-learning-based objective detection such as variants of Faster R-CNN and YOLO (hereafter referred to as "deep-learning method").

However, these methods require human manipulation for predefined amplitude, frequency intervals and training process. In addition, their optimal setting is case-dependent. In this context, these methods cannot be considered as a fully-automated peak-picking method without any prior setting and human manipulation.

Dr. Jin said, "Stay-cables have remarkable physical characteristics. The modal frequencies of the stay-cables appear periodically or quasi-periodically with high-amplitudes. To enjoy the domain knowledge, we can find suitable methods from other disciplines. For example, our heart-beat makes periodic peaks in ECG signals and we can compute heart rate by counting the periodic peaks in real time. The biomedical discipline is one of the specialized fields for analyzing periodic peaks. We can adopt one of the methods from this discipline to exploit the periodic characteristics of the modal frequencies."

When conceptualizing the developed method, the research team made several criteria to select the most suitable method from other disciplines. First, it does not require any hyper-parameters to be predefined by the user. Second, it should be fairly robust against noise and variabilities in signals. Third, their computational complexity and costs should be affordable for near real-time. Based on these three criteria, research team selected three algorithms from other disciplines, such as Bio and Brain Engineering, Raman Spectroscopy and Statistical Process Control. Since each method is developed based on the specific purpose of their original domain, the research team tailored them to accelerate research synergy.

The newly developed method was evaluated using real stay-cables in three cable-stayed bridges in South Korea (total 60 dataset). The proposed method compared with the deep-learning method extensively. The deep-learning method does not work well, when the characteristics of the real peaks differ from those of the peaks in the training data. The experimental results show that the developed method performs well regardless of the characteristics of the real PSD. Also, it outperforms state-of-art methods in terms of accuracy and robustness. And it does not need any prerequisites. Finally, its computational cost is very cheap (less than 0.5 seconds in standard personal computers) to be embedded into low-cost smart sensors.

Dr. Jin said, "For engineering, the most important ingredient is our domain knowledge. It can help us to define our problem and develop a proper solution. We will apply our method to other field-data for its generalization and improve it. Such iterative process is inherent and very important. We hope that our method can guide us to take a step towards autonomous monitoring systems."

LUGANO, 6 May, 2021- New research investigating for the first time the effects of modified intermittent fasting (MIF) on the skin of people with psoriasis has yielded promising results. Preliminary study findings presented today at the EADV Spring Symposium, show a significant reduction in scaling and thickness in patients with mild psoriasis after following a MIF 5:2 diet (eating normally for 5 days and restricting calorie intake on 2 non-consecutive days).

Psoriasis is a chronic, systemic immune-mediated inflammatory disease that causes raised plaques and scales on the skin's surface. The disease affects between 2-3% of the worlds' adult population, and

"We had observed positive results in mice with gut inflammation and psoriasis, with inflammation in the gut driving cutaneous symptoms," shares Dr Lynda Grine, Postdoctoral Researcher, Department of Dermatology, Ghent University, Belgium "Through scientific curiosity and my own experience with fasting as a Muslim, I wanted to find out whether dietary intervention would have the same effects on human patients with psoriasis."

MIF is a form of intermittent fasting which requires participants to restrict calorie intake for a certain amount of time. It is often viewed as a more manageable form of fasting, allowing participants to adjust the rules to accommodate with their personal lives. Popular MIF diets include the 16:8 (fast for 16 hours and eat for 8) and 5:2 diet, with the latter being used as the dietary intervention for this study.

A total of 24 subjects were enrolled in the study, with one group of 12 participants instructed to modify their diet with MIF for 12 weeks, and the other 12 participants continuing on their regular diet. Replicating the 5:2 diet, the fasting group were asked to consume a total of 500 kcal twice per week on 2 non-consecutive days, but were free to consume their usual daily calorie intake for the remaining 5 days of the week. During the trial, 2 patients were excluded: 1 due to start of antibiotic use and 1 due to loss to follow-up.

Objectively, PASI (a tool used to measure the severity and extent of psoriasis) and Body Surface Area (BSA) did not differ significantly between fasting and regular diet, although PASI reduced in the fasting group (p

"The effect of dietary interventions on skin health is a stimulating field of research in dermatology. The results of this study add to the growing body of evidence being undertaken to understand the relationship between the gut and skin, with some promising results for patients and the disease management of psoriasis." Says Prof. Marie-Aleth Richard, EADV Board Member and Professor at the University Hospital of La Timone, Marseille.

Researchers at Chinese Academy of Science and Osaka University show that, unlike the crystalline close packing of spheres, random close packing or jamming of spheres in a container can take place in a broad range of densities and anisotropies. Furthermore, they show that such diverse jammed states are all just marginally stable and exhibit common universal critical properties.

Osaka, Japan - Scientists at the theoretical institutes, Chinese Academy of Science and Cybermedia Center at Osaka University performed extensive computer simulations to generate and examine random packing of spheres. They show that the "jamming" transition, in which a free-flowing material becomes stuck, occurs with universal features despite the diversity of their details. This work may shed light on the physics of amorphous materials and optimization problems in computer science which are intimately related to the mathematics of sphere packings.

How many oranges can fit in a spherical bowl? This seemingly prosaic question actually leads to a fascinating topic of efficient packing theory and the concept of "jamming." While it is known that spheres can be packed regularly to take up a maximum of 74% of the volume, the corresponding limit for random packings is thought to be around 64%, but this has not been proved. The solution is related to the ability of certain soft matter materials, including sand, colloid, foam, or polymers to become jammed by compression or shear. You can experiment for yourself using a box of cereal that will suddenly stop pouring.

Now, the team used simulated collections of frictionless spheres on supercomputers and found that jammed states can be obtained either by compression or by shear in a broad range of densities larger than 64% and with a broad range of anisotropies. They found, the diverse jammed states are all at the verge of mechanical stability and exhibit the same critical properties. "We demonstrated that compression and shear-jammed frictionless packings can be described under a unified framework," first author Yuliang Jin says. This implies the marginal stability is the robust, key mechanism which underlies jamming.

In this research, the coordination number refers to the number of neighbors a sphere has. The team showed that plots of the coordination number at various distances collapse onto the same curve regardless of particle density of the jammed states. "The densest packing of spheres represents a unique structure. Conversely, random packing, as with the atoms in a glass, can lead to arrangements with various densities depending on the method of compression and shear applied," senior author Hajime Yoshino says. This research, which sheds light on the efficient packing of solid objects, may lead to new ideas for the industrial production of glasses, foams, and other jammable materials.

A KAIST research team has developed a new technology that enables to process a large-scale graph algorithm without storing the graph in the main memory or on disks. Named as T-GPS (Trillion-scale Graph Processing Simulation) by the developer Professor Min-Soo Kim from the School of Computing at KAIST, it can process a graph with one trillion edges using a single computer.

Graphs are widely used to represent and analyze real-world objects in many domains such as social networks, business intelligence, biology, and neuroscience. As the number of graph applications increases rapidly, developing and testing new graph algorithms is becoming more important than ever before. Nowadays, many industrial applications require a graph algorithm to process a large-scale graph (e.g., one trillion edges). So, when developing and testing graph algorithms such for a large-scale graph, a synthetic graph is usually used instead of a real graph. This is because sharing and utilizing large-scale real graphs is very limited due to their being proprietary or being practically impossible to collect.

Conventionally, developing and testing graph algorithms is done via the following two-step approach: generating and storing a graph and executing an algorithm on the graph using a graph processing engine.

The first step generates a synthetic graph and stores it on disks. The synthetic graph is usually generated by either parameter-based generation methods or graph upscaling methods. The former extracts a small number of parameters that can capture some properties of a given real graph and generates the synthetic graph with the parameters. The latter upscales a given real graph to a larger one so as to preserve the properties of the original real graph as much as possible.

The second step loads the stored graph into the main memory of the graph processing engine such as Apache GraphX and executes a given graph algorithm on the engine. Since the size of the graph is too large to fit in the main memory of a single computer, the graph engine typically runs on a cluster of several tens or hundreds of computers. Therefore, the cost of the conventional two-step approach is very high.

The research team solved the problem of the conventional two-step approach. It does not generate and store a large-scale synthetic graph. Instead, it just loads the initial small real graph into main memory. Then, T-GPS processes a graph algorithm on the small real graph as if the large-scale synthetic graph that should be generated from the real graph exists in main memory. After the algorithm is done, T-GPS returns the exactly same result as the conventional two-step approach.

The key idea of T-GPS is generating only the part of the synthetic graph that the algorithm needs to access on the fly and modifying the graph processing engine to recognize the part generated on the fly as the part of the synthetic graph actually generated.

The research team showed that T-GPS can process a graph of 1 trillion edges using a single computer, while the conventional two-step approach can only process of a graph of 1 billion edges using a cluster of eleven computers of the same specification. Thus, T-GPS outperforms the conventional approach by 10,000 times in terms of computing resources. The team also showed that the speed of processing an algorithm in T-GPS is up to 43 times faster than the conventional approach. This is because T-GPS has no network communication overhead, while the conventional approach has a lot of communication overhead among computers.

Prof. Kim believes that this work will have a large impact on the IT industry where almost every area utilizes graph data, adding, "T-GPS can significantly increase both the scale and efficiency of developing a new graph algorithm."

Trust, safety and security are the most important factors affecting passengers' attitudes towards self-driving cars. Younger people felt their personal security to be significantly better than older people.

The findings are from a Finnish study into passengers' attitudes towards, and experiences of, self-driving cars. The study is also the first in the world to examine passengers' experiences of self-driving cars in winter conditions.

The findings were published in Transportation Research Part F: Traffic Psychology and Behaviour. The study was carried out in collaboration between the University of Eastern Finland and Tampere University.

Self-driving cars face huge expectations in Europe and the United States, which is why passengers' experiences and expectations stand at the core of their development. The Finnish study explored passengers' experiences in Helsinki, the capital of Finland, and in Muonio, a small town in Finnish Lapland. In Helsinki, passengers used a driverless shuttle bus in two test areas. In Muonio, local residents travelled with an autonomous car in heavy winter conditions on the main road. The quantitative survey included 141 people, and 70 people participated in a qualitative interview.

The researchers charted passengers' attitudes towards self-driving cars, factors influencing their positive or negative attitudes, and factors that could encourage passengers to use self-driving cars.

According to the study, people's positive attitude towards self-driving cars was most influenced by trust, safety and security. However, people were not prepared to accept technological errors in self-driving cars, even though it is understood that the technology is still under development.

Young passengers clearly had more confidence in the safety and security of self-driving cars than older passengers, and students estimated their ability to act in an emergency to be better than the employed. Winter conditions had no significant impact on people's attitudes towards self-driving cars. There was also no significant difference between the genders.

"Finns have a pragmatic approach to new technology: if the new mode of transport facilitates everyday life and is affordable, there seems to be no obstacle to it becoming mainstream," Professor Arto O. Salonen from the University of Eastern Finland says.

Children born in December are almost twice as likely to be diagnosed with a learning disorder as those born in January. ADHD was found not to affect the association between month of birth and the likelihood of a learning disability diagnosis.

The new, register based study included children born in Finland between 1996 and 2002. Of nearly 400,000 children, 3,000 were diagnosed with a specific learning disorder, for example, in reading, writing or math by the age of ten.

"We were familiar with the effects of the relative age to the general school performance, but there were no previous studies on the association between clinically diagnosed specific learning disorders and relative age, which is why we wanted to study it," says Doctoral Candidate, MD Bianca Arrhenius from the Centre for Child Psychiatry at the University of Turku, Finland.

In previous studies, children born later in the year, and therefore younger than their classroom peers, have been found to be at increased risk of psychiatric disorders, low academic achievement, and being bullied.

ADHD does not affect learning disabilities

Many children with learning disabilities are diagnosed with ADHD. The study compared children with both learning disability diagnosis and ADHD separately from children with learning disabilities but without ADHD, and ADHD was found not to affect the association between month of birth and the likelihood of a learning disability diagnosis.

"This finding was surprising. In children referred to specialist care, the problems are typically complex. We did not expect the impact of relative age on "pure" learning disorder to be so significant, given previous research findings on relative age to ADHD," says Dr Arrhenius.

"Diagnosing learning disorders with psychological tests also takes the exact age of the child better into account compared with the methods used in diagnosing ADHD. For this reason, too, we expected more moderate differences between the months of birth. It seems that relatively young children are more easily sent to specialized health care," Arrhenius ponders.

Aiming for equality

Research shows that teachers, health care personnel, and parents need to be aware of the phenomenon of relative age, especially when assessing a child's learning ability.

"There is a risk of both over- and under-diagnosis, meaning that the youngest in the class are proportionately diagnosed so much more that the older students in the class may even be deprived of the diagnosis and rehabilitation they need. A more systematic screening for learning disabilities could be one approach that would even out the effect of relative age on referrals to specialized health care," says Arrhenius.

Research led by the University of Liverpool, in partnership with Johnson Matthey PLC and Loughborough University is making significant progress in the development of stable and practical electrolytes for lithium-oxygen batteries.

The lithium-oxygen (Li-O2) battery (or lithium-air battery), consisting of Li-metal and a porous conductive framework as its electrode's releases energy from the reaction of oxygen from the air and lithium. The technology is in its infancy, but in theory could provide much greater energy storage than the conventional lithium-ion battery.

In a paper published in the journal Advanced Functional Materials, Professor Laurence Hardwick from the University of Liverpool's Stephenson Institute for Renewable Energy (SIRE) and colleagues meticulously characterised and developed electrolyte formulations that significantly minimises side reactions within the battery to enable improved longer cycle stability.

According to lead author of the paper, Dr Alex Neale who is also with SIRE, the research demonstrates that the reactivity of certain electrolyte components can be switched off by precise control of component ratios.

Dr Neale said: "The ability to precisely formulate the electrolyte using readily-available, low volatility components enabled us to specially tailor an electrolyte for the needs of metal-air battery technology that delivered greatly improved cycle stability and functionality."

"The outcomes from our study really show that by understanding the precise coordination environment of the lithium ion within our electrolytes, we can link this directly to achieving significant gains in electrolyte stability at the Li metal electrode interface and, consequently, enhancements in actual cell performance."

Dr Pooja Goddard, from Loughborough University's Department of Chemistry, said: "It was exciting to see through the use of both calculations and experimental data we were able to identify the key physical parameters that enabled the formulations to become stable against the lithium metal electrode interface."

The designed electrolytes provide new benchmark formulations that will support ongoing investigations within our research groups to understand and develop new, and practically viable, cathode architectures to reduce round-trip inefficiencies and further extend cycle lifetimes.

The collaborative research between the two University research groups in Liverpool and Loughborough and Johnson Matthey PLC was made possible by support from an Innovate UK Grant that enables industry and academia to work together to tackle technology focused research challenges.

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Photocatalytic biomass conversion is an ideal way of generating syngas (H2 and CO) via C-C bond cleavage, which is initiated by hydrogen abstraction of O/C-H bond. However, the lack of efficient electron-proton transfer limits its efficiency. Conversional gasification of biomass into syngas needs to be operated at high temperature (400-700 °C).

Recently, a group led by Prof. WANG Feng from the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. WANG Min from Dalian University of Technology, proposed a new method to realize photocatalytic conversion of biopolyols to syngas at room temperature with high efficiency.

This study was published in Journal of the American Chemical Society on April 27.

The researchers prepared surface sulfate ions modified CdS catalyst ([SO4]/CdS), which could simultaneously increase both the electron and proton transfer, thereby facilitating the generation of syngas mixture from biopolyols with high activity and selectivity.

In situ characterizations combined with theoretical calculations demonstrated that the surface sulfate ion [SO4] was bifunctional, serving as the proton acceptor to promote proton transfer, and increasing the oxidation potential of the valence band to enhance electron transfer.

Compared with pristine CdS, [SO4]/CdS exhibited 9-fold higher CO generation rate and 4-fold higher H2 generation. Through this method, a wide range of sugars, such as glucose, fructose, maltose, sucrose, xylose, lactose, insulin, and starch, were facilely converted into syngas.

This study reveals the pivotal effect of surface sulfate ion on electron-proton transfer in photocatalysis and provides a facile method for increasing photocatalytic efficiency.

Scientists at Tokyo Institute of Technology experimentally verify the existence of exotic surface conduction states in topological semimetals (TSMs), materials that lie at the boundary between conductors and insulators, by performing voltage scans of these surface states on a thin film sample of a TSM. The findings can pave the way for future study and exploitation of such conduction states in realizing novel, quantum transport phenomena.

All of us are probably familiar with the idea of conductors and insulators. But what would you call a material that can conduct on the surface but insulate on the inside? Physicists call it a "topological insulator" (TI), a term that highlights the geometric aspect of its strange conduction behavior. Even stranger than TIs are "topological semimetals" (TSMs)-- bizarre materials that straddle the boundary between metals (conductors) and insulators.

While TIs have found practical applications thanks to their unusual properties, notably in advanced optoelectronic devices, TSMs are still largely a curiosity among material scientists. "In TIs, the surface conduction states can be isolated from the bulk insulating states, whereas in typical TSMs, such as Dirac and Weyl semimetals, the bulk and surface states touch at points called 'Weyl nodes,' leading to an interplay between them," explains Associate Professor Masaki Uchida from Tokyo Institute of Technology, Japan, whose research is focused on topological materials.

According to theoretical predictions, an interesting consequence of such an interplay is the formation of a coupled pair of electronic "Weyl orbits" under a magnetic field on opposite surfaces of a TSM that can lead to a novel 2D quantum transport. However, the experimental verification of Weyl orbits has, so far, remained challenging due to the seeming lack of a unique signature. Now, a new study by a team of scientists from Japan, led by Dr. Uchida, might change all that.

Published in Nature Communications, the study focuses on the unique spatial distribution of the Weyl orbits. Specifically, scientists carried out a mapping of Weyl orbit "Quantum Hall" (QH) states under the influence of electric voltages applied on the top and bottom surface of a TSM sample comprising a 75-nm-thick film of (Cd1-xZnx) 3 As2. "The key observation to distinguish the Weyl orbit from a TI-like orbit is the response of the surface transport to electric fields applied in a dual-gate device configuration," says Dr. Uchida.

Scientists began by studying the magnetic field dependence of film resistance at zero gating voltages at a temperature of 3K (270°C) and ensured that the film was thick enough to let the Weyl orbits form. Initially, bulk transport dominated the conduction due to a high electron density. However, as scientists depleted the electrons by applying gating voltages, surface transport and its evolution into QH states became more prominent.

Next, the scientists studied the influence of gating voltage scans on these QH states in presence of a strong magnetic field and observed a peculiar striped pattern in the mapped states due to a modulation in their electron density, suggesting the presence of a coupled Weyl orbit pair!

The research team is thrilled by this finding. An excited Dr. Uchida concludes, "Our work revealing the role of unique distribution of Weyl orbits in quantum transport can open doors to finding various exotic surface transport phenomena in TSMs and controlling them via external fields and interface engineering."

The hunt for these novel quantum phenomena is on, with new and exciting discoveries just be around the corner!