Culture

New research has determined the prevalence of private security systems may be robbing the general public of the police services they need.

Dr. Ross Hickey is an economist in UBC Okanagan's Faculty of Management and the Irving K. Barber Faculty of Arts and Social Sciences. Along with a team of researchers, Hickey examined data from a social survey of Canada victimization, where people answered whether they had added security measures to their homes to protect themselves from crime.

"We are seeing more expenditures on private security systems installed in homes and, as economists, we have to ask why. We know that crime rates are down and expenditure on police is up," says Hickey. "But private security purchases are at an all-time high."

Hickey says the research team first thought about the classic supply and demand equations. The government provides the supply, or resources, for policing and there is a demand for public protection. However, when you combine a supply of private security products, then add criminals to the mix, Hickey says the basic supply and demand equation doesn't add up.

There are many different types of security measures people can take--anything from putting bars on windows to getting a dog, or adding motion-detection lights, house alarms and security cameras. And while they may make people feel more secure, it's also been proven that a barking dog may deter a thief more effectively than cameras and alarms. Hickey says security systems that automatically alert police, even though it may be a false alarm, can divert police from other duties.

"All of these innovations in private security don't prevent the crime, they increase the chances of the person getting caught. When the police are called to homes using these technologies, we see the police being taken away from responding to another, perhaps, more urgent call," says Hickey.

Hickey says their research demonstrates a classic case of inequity between segments of society.

"This is a dimension of inequity that doesn't show up directly," he says. "The inequity is in how some people are accessing this public good. It is available for everybody but some people are getting more of it, because they have chosen to install these private systems. And police are responding to those systems."

The research, says Hickey, means that municipalities should consider police budgets differently than they currently do. Right now, just adding more money to the system does not change the inequity that will continue with the prevalence of home security systems.

"We need to think more carefully about this. In a world where private security investments are happening, we may need to look at different methods of funding the police," he says.

Hickey says just adding extra funding into the mix is not the solution. Currently, people are not being uniformly protected by police services. And the police are being drawn toward particular segments of society who have privately invested in their own home protective measures.

"Are the people with lower incomes, or those living on the street, getting the same service from police? And we have to ask--if the city adds more police services next year, is that really going to make downtown much safer?"

CORVALLIS, Ore. - Selectively cutting trees in riparian zones to aid forest restoration can be done without adversely affecting streams' water temperature as long as the thinning isn't too intensive, new research by Oregon State University shows.

Published in PLOS One, the study led by OSU College of Agricultural Sciences graduate student David Roon is one of the few to quantify restorative thinning's effects on forest streams.

"We don't know much about what happens with the more subtle changes in shade and light that come with thinning," Roon said. "Most of the research so far has looked at the effects of clearcutting with no stream-side buffer at all, or harvests outside of an untouched buffer area. And regulatory requirements tend to look at single descriptors of stream temperature - the warmest it gets in the middle of summer, for example - and those descriptors possibly don't do a thorough job of explaining thermal influences on ecological processes."

Riparian zones - lands near streams, lakes, ponds, etc. - have unique soil and vegetation characteristics that are influenced strongly by the presence of water. Riparian zones make up less than 1% of the total area of the American West, contrast significantly with the West's arid uplands and provide habitat for a range of endangered and threatened species.

In riparian restoration, conservation managers look at an area's functional and structural elements - climate, soils, weather patterns, hydrology, plants, wildlife and socioeconomic use patterns - and actively or passively try to set in motion processes that enable natural ecological conditions to return.

Riparian forests in the Pacific Northwest, Roon explains, were "extensively altered" by previous timber harvesting practices that persisted for much of the 20th century, including clearcutting trees right up to waters' edge.

Leaving a buffer zone of vegetation alongside streams is critical for wildlife, especially salmon and trout. A riparian buffer also provides a wide array of ecosystem services for riparian forests and streams including filtering sediment and excessive nutrients and providing shade to keep water temperatures cool, as well as storing carbon. In addition, mature trees next to the stream will eventually fall in, creating important habitat for fish.

Roon and collaborators Jason Dunham and Jeremiah Groom examined the effects of riparian thinning on shade, light and stream temperature in three small watersheds in second-growth redwood forests in northern California. Dunham is an aquatic ecologist with the U.S. Geological Survey who has a courtesy appointment in OSU's Department of Fisheries and Wildlife. Groom, who holds two graduate degrees from Oregon State, operates Groom Analytics LLC, a data analysis consulting firm, and is an expert on the effects of forest harvest on stream temperatures.

Northern California is well known for its groves of large, iconic redwood trees. However, intensive logging removed most of the old-growth forests from this region and less than 10% of those forests remain.

Foresters are interested in whether thinning can be applied to young forests to help speed up the recovery of older redwood forests. Most forest restoration efforts so far have been focused on upland forests - those where soils do not stay saturated for extended periods - and have been generally successful; now attention is turning to young forests in riparian zones.

The OSU research took place both on private timber land and in nearby Redwood National Park, bringing together land managers with different natural resource management requirements with the common goal of understanding the effects of thinning on aquatic ecosystems. In this study the focus was on stream temperatures - an important consideration for the sensitive fish and amphibians that live in the watersheds in the region.

The large-scale field study enabled the scientists to measure conditions before and after experimental thinning treatments. These types of field experiments are rare in riparian forests, which are carefully protected.

"The power of these types of field experiments is that they can help us more directly attribute changes to the thinning treatment itself and remove other factors that often confound these types of studies," Roon said. "Responses to the thinning differed greatly depending on the intensity. In the watersheds where thinning treatments were more intensive, the reductions in shade and increases in light were sufficient to change the stream thermal regimes both locally and downstream. However, where the thinning treatments were less intensive, smaller reductions in shade and light resulted in minimal changes in stream temperatures."

That means, Roon said, at lower intensity levels thinning within riparian zones in second-growth redwood forests looks like a feasible restoration strategy. This study is an important step toward making robust decisions regarding whether thinning, and how much of it, can be done without having adverse effects on streams.

Future research, he added, could examine thinning treatments with a wider range of intensities. Roon also pointed out that the results were specific to the cool, coastal climates of the redwoods and would not necessarily apply to locations further inland.

"We also need to understand the effects of thinning in other locations under a range of different contexts," he said. "Until we know more about the effects of thinning on stream temperatures across a broader range of conditions, it should still be approached with caution."

HOUSTON - (March 1, 2021) - Rice University physicists have discovered a way to trap the world's coldest plasma in a magnetic bottle, a technological achievement that could advance research into clean energy, space weather and astrophysics.

"To understand how the solar wind interacts with the Earth, or to generate clean energy from nuclear fusion, one has to understand how plasma -- a soup of electrons and ions -- behaves in a magnetic field," said Rice Dean of Natural Sciences Tom Killian, the corresponding author of a published study about the work in Physical Review Letters.

Using laser-cooled strontium, Killian and graduate students Grant Gorman and MacKenzie Warrens made a plasma about 1 degree above absolute zero, or approximately -272 degrees Celsius, and trapped it briefly with forces from surrounding magnets. It is the first time an ultracold plasma has been magnetically confined, and Killian, who's studied ultracold plasmas for more than two decades, said it opens the door for studying plasmas in many settings.

"This provides a clean and controllable testbed for studying neutral plasmas in far more complex locations, like the sun's atmosphere or white dwarf stars," said Killian, a professor of physics and astronomy. "It's really helpful to have the plasma so cold and to have these very clean laboratory systems. Starting off with a simple, small, well-controlled, well-understood system allows you to strip away some of the clutter and really isolate the phenomenon you want to see."

That's important for study co-author Stephen Bradshaw, a Rice astrophysicist who specializes in studying plasma phenomena on the sun.

"Throughout the sun's atomosphere, the (strong) magnetic field has the effect of altering everything relative to what you would expect without a magnetic field, but in very subtle and complicated ways that can really trip you up if you don't have a really good understanding of it," said Bradshaw, an associate professor of physics and astronomy.

Solar physicists rarely get a clear observation of specific features in the sun's atmosphere because part of the atmosphere lies between the camera and those features, and unrelated phenomena in the intervening atmosphere obscures what they'd like to observe.

"Unfortunately, because of this line-of-sight problem, observational measurements of plasma properties are associated with quite a lot of uncertainty," Bradshaw said. "But as we improve our understanding of the phenomena, and crucially, use the laboratory results to test and calibrate our numerical models, then hopefully we can reduce the uncertainty in these measurements."

Plasma is one of four fundamental states of matter, but unlike solids, liquids and gases, plasmas aren't generally part of everyday life because they tend to occur in very hot places like the sun, a lightning bolt or candle flame. Like those hot plasmas, Killian's plasmas are soups of electrons and ions, but they're made cold by laser-cooling, a technique developed a quarter century ago to trap and slow matter with light.

Killian said the quadrupole magnetic setup that was used to trap the plasma is a standard part of the ultracold setup that his lab and others use to make ultracold plasmas. But finding out how to trap plasma with the magnets was a thorny problem because the magnetic field plays havoc with the optical system that physicists use to look at ultracold plasmas.

"Our diagnostic is laser-induced fluorescence, where we shine a laser beam onto the ions in our plasma, and if the frequency of the beam is just right, the ions will scatter photons very effectively," he said. "You can take a picture of them and see where the ions are, and you can even measure their velocity by looking at the Doppler shift, just like using a radar gun to see how fast a car is moving. But the magnetic fields actually shift around the resonant frequencies, and we have to disentangle the shifts in the spectrum that are coming from the magnetic field from the Doppler shifts we're interested in observing."

That complicates experiments significantly, and to make matters even more complicated, the magnetic fields change dramatically throughout the plasma.

"So we have to deal with not just a magnetic field, but a magnetic field that's varying in space, in a reasonably complicated way, in order to understand the data and figure out what's happening in the plasma," Killian said. "We spent a year just trying to figure out what we were seeing once we got the data."

The plasma behavior in the experiments is also made more complex by the magnetic field. Which is precisely why the trapping technique could be so useful.

"There is a lot of complexity as our plasma expands across these field lines and starts to feel the forces and get trapped," Killian said. "This is a really common phenomenon, but it's very complicated and something we really need to understand."

One example from nature is the solar wind, streams of high-energy plasma from the sun that cause the aurora borealis, or northern lights. When plasma from the solar wind strikes Earth, it interacts with our planet's magnetic field, and the details of those interactions are still unclear. Another example is fusion energy research, where physicists and engineers hope to recreate the conditions inside the sun to create a vast supply of clean energy.

Killian said the quadrupole magnetic setup that he, Gorman and Warrens used to bottle their ultracold plasmas is similar to designs that fusion energy researchers developed in the 1960s. The plasma for fusion needs to be about 150 million degrees Celsius, and magnetically containing it is a challenge, Bradshaw said, in part because of unanswered questions about how the plasma and magnetic fields interact and influence one another.

"One of the major problems is keeping the magnetic field stable enough for long enough to actually contain the reaction," Bradshaw said. "As soon as there's a small sort of perturbation in the magnetic field, it grows and 'pfft,' the nuclear reaction is ruined.

"For it to work well, you have to keep things really, really stable," he said. "And there again, looking at things in a really nice, pristine laboratory plasma could help us better understand how particles interact with the field."

Osaka, Japan - Osaka University researchers employed machine learning to design new polymers for use in photovoltaic devices. After virtually screening over 200,000 candidate materials, they synthesized one of the most promising and found its properties were consistent with their predictions. This work may lead to a revolution in the way functional materials are discovered.

Machine learning is a powerful tool that allows computers to make predictions about even complex situations, as long as the algorithms are supplied with sufficient example data. This is especially useful for complicated problems in material science, such as designing molecules for organic solar cells, which can depend on a vast array of factors and unknown molecular structures. It would take humans years to sift through the data to find the underlying patterns—and even longer to test all of the possible candidate combinations of donor polymers and acceptor molecules that make up an organic solar cell. Thus, progress in improving the efficiency of solar cells to be competitive in the renewable energy space has been slow.

Now, researchers at Osaka University used machine learning to screen hundreds of thousands of donor:acceptor pairs based on an algorithm trained with data from previously published experimental studies. Trying all possible combinations of 382 donor molecules and 526 acceptor molecules resulted in 200,932 pairs that were virtually tested by predicting their energy conversion efficiency.

"Basing the construction of our machine leaning model on an experimental dataset drastically improved the prediction accuracy," first author Kakaraparthi Kranthiraja says.

To verify this method, one of the polymers predicted to have high efficiency was synthesized in the lab and tested. Its properties were found to conform with predictions, which gave the researchers more confidence in their approach.

"This project may contribute not only to the development of highly efficient organic solar cells, but also can be adapted to material informatics of other functional materials," senior author Akinori Saeki says.

We may see this type of machine learning, in which an algorithm can rapidly screen thousands or perhaps even millions of candidate molecules based on machine learning predictions, applied to other areas, such as catalysts and functional polymers.

With their exuberant colours, fiery personalities and captivating courtship displays, the fairy wrasses are one of the most beloved coral reef fish. Despite this, the evolutionary history of its genus was not well understood - until now.

Fairy wrasses diverged in form and colour after repeated sea level rises and falls during the last ice age, finds a new study. Published in top journal Systematic Biology, it employed a novel genome-wide dataset to make this discovery.

Lead author, ichthyologist and PhD candidate at the University of Sydney, Mr Yi-Kai (Kai) Tea, says that the fish's divergence occurred rapidly and over a short amount of time.

"Although the fairy wrasses split from their most common ancestor some 12 million years ago, it was only within the last 2-5 million years ago that much of their divergences took place, in the Pliocene/Pleistocene epoch," said Mr Tea, a researcher in the School of Life and Environmental Sciences.

"They developed distinct colours and forms in a sort of evolutionary arms race, putting on dazzling displays in an effort to court females and chase off rival males. Also, sea level changes caused groups to become isolated, and therefore evolve separately. The repeated rise and fall of sea levels acted like a 'species pump', propelling fish into the Indian Ocean and even as far as the Red Sea. Most of this movement, however, occurred in the Pacific Ocean, in particular, around the Indo-Australian Archipelago."

Mr Tea completed the work under the supervision of Professors of Molecular Evolution, Simon Ho and Nathan Lo.

Decoding fish DNA

Despite the vast variation in colour and form, many species of fairy wrasses have highly conserved, or similar, regions of their genome. This poses a challenge in trying to reconstruct their evolutionary history.

The current study used an approach that had not been previously attempted on fairy wrasses: by combining genome-wide ultra-conserved elements with mitochondrial DNA, the researchers reconstructed a robust evolutionary tree. Using that, they began to tease apart the reason behind the fish's diversification.

Do a little dance, make a little love

In addition to sea level fluctuations, male fairy wrasses (as with many animals, the more colourful sex) developed their bright colours and individual forms to court females.

"They do a little dance, and they are capable of changing colours, sometimes temporarily flashing bright, iridescent colours. They also do this to ward off rival males," said Mr Tea. "In a reef where multiple species often occur, there is increased pressure for males to attract not only a female's attention, but also the female of the correct species."

"We have only just begun scratching the surface of this exciting group, and more work still needs to be done in order to fully understand the drivers of species diversification," he continued.

That work, and the present study, might be germane to reef conservation and management, too. For example, the finless 'mutant wrasse', an Australian endemic species restricted to a narrow distribution of reefs in far northwest Western Australia, is listed as vulnerable on the International Union for Conservation of Nature Red List of threatened species. The species has been placed in its own genus, with a single species. However, Mr Tea's study finds strong evidence that this species is simply a derived fairy wrasse, and that its loss of fins likely resulted from it being 'bottlenecked' in a narrow area.

Raspberry muffins are in our future.

Washington State University scientists have figured out a way to treat raspberries before they're frozen so that they maintain their structure when thawed.

The tart little berries are very delicate and freezing damages their cells. They turn to mush when baked and leak juice into the surrounding baked product, making them unattractive and diluted in flavor. As a result, frozen raspberries are rarely used in baking, whether at home or in commercial bakeries. But that's about to change.

In a recent article published in Food and Bioprocess Technology, Shyam Sablani and his team describe their method of reducing syneresis, or the leaking out of liquid.

Washington State is responsible for approximately 95% of processed (frozen) red raspberry production in the nation.

"We wanted to help the Washington raspberry industry," said Sablani, a professor in WSU's Department of Biological Systems Engineering. "Frozen raspberries are good in smoothies and things like that, but not in baking. We wanted to find a way to keep them intact through the baking process."

Doing that requires three separate steps, all of them long-proven as safe for people to eat. First, they infuse each berry with pectin, which is often used as a thickener in cooking and baking, and calcium, which plays an important role in maintaining the cell-wall structure by forming a firm gel-like structure. Second, the raspberries are partially dried, reducing the damage from ice crystals in the thawed fruit.

"You can't dry them completely, you don't want them to look like raisins," Sablani said. "But removing part of the water still allows the raspberries to maintain their color and shape."

The third step is to cover the berries with a food grade edible coating that's often used in coating pre-baked frozen pies and pizzas.

"That way, when the raspberry is being frozen, it won't leak any juice and the coating will protect the moisture that's left," Sablani said.

He and his team ran hundreds of tests to get the best results for each step, then did their own hands-on testing.

"My Ph.D. student, Armando Quintanilla, made raspberry muffins and cakes many times," he said. "They were really tasty, and the raspberries held their shape and juices well."

After their own testing, Sablani and his team partnered with a commercial baker in Western Washington who made two batches of raspberry muffins. One had frozen berries bought from a store, the other berries frozen using Sablani's new method. The baker did not know which frozen berries were which.

Then both muffins were served in a blind taste-test to members of the Washington raspberry council during their annual meeting (pre-COVID 19 pandemic).

"They could tell a difference right away," Sablani said. "The store-bought raspberries bled juice all over with no big chunks of fruit. Ours kept their shape with very little bleeding."

After impressing industry representatives, the next step is to start work on increasing the process to commercial scale. That means working with raspberry processors who would need to add the new capabilities at their facilities.

It also requires food makers to include more baked raspberry items in their product lines. That means doing consumer testing to gauge the potential market, so it may be a while before this breakthrough leads to raspberry muffins or bagels becoming a grocery store staple.

"We're early on in this work," Sablani said. "But we're excited and think there will be a market. People love raspberries; they've got lots of flavor."

The work for this project was funded by a Washington State Department of Agriculture Specialty Crop Block Grant.

Sablani plans to apply for a larger grant later this year to further develop the process on a commercial scale and include market testing.

Making cheese leaves a lot to chance as a batch could be ripened for months or even years before a problem is discovered, which could send a prized batch of cheddar to be sold off cheap as an ingredient for processed cheese.

It's part of why cheese is so complex and expensive to make - a factory could invest lots of time and money into what they think will be a top-graded batch, only to discover it's a flop when it's too late to fix.

But new research from RMIT University in Melbourne, Australia allows quality to be checked much earlier and more precisely in the process, giving manufacturers a better chance to react to issues with the ripening process.

Dr Roya Afshari said the team devised a method to expose cheese's biomarkers - or fingerprints - to show unique combinations of things like chemicals and milk-derived components that make up the perfect block.

"Once we know the chemical profile of a successful cheese, we can compare it to new batches as soon as 30 days into the ageing process," she said.

"It's like a pregnancy screening test for cheese - we analyse the biological data early in the development to see if there are any red flags.

"This could be done alongside traditional analyses like tasting to highlight future potential problems."

The team looked at different commercial cheddar cheeses in Australia and applied multi-omics - a kind of biological analysis typically used in human medicine to detect diseases early.

Researchers studied the biological make up of different brands and grades of cheese and worked with data experts to interpret and compare the results for known batches.

"Once we knew the unique properties of a finished cheese, we compared them to ripening batches and worked out which compounds distinguished the best cheeses," Afshari said.

With larger datasets, it will be possible for these techniques to let manufacturers know if their batch will age properly, because they can check to see if the key compounds have developed early in the ripening process or just as importantly that the bad ones haven't - like having a crystal ball.

What's more, the practice of grading a cheese's quality and maturity will no longer need to be left to subjective human senses.

Afshari said incorporating multi-omics analysis into testing cheese gives professional cheese graders more tools to accurately assess for quality.

"Cheese chemical fingerprints can be compared against those found in the perfect product, along with traditional grading methods.

"Now we can identify different types and grades of cheese more accurately than a taste test."

The researchers have published three recent studies demonstrating how interpreting the biological profile of cheese can aid manufacturing and grading.

In separate studies, they used multi-omics analyses to differentiate cheddar cheeses based on their age and brand, compare cheese of varying quality and group artisanal and industrial cheddar cheeses based on type and brand.

From cheese to wine

The method devised by the RMIT team is scalable and with more development could be used to test just about any food or beverage product, including wine, for quality and authenticity.

This is significant, as counterfeit wines are a multi-billion-dollar problem plaguing the industry.

Chief supervisor of this research project Professor Harsharn Gill said the days of counterfeit food and drink products could be numbered, as bioanalysis technology becomes commercially available.

"Some product's fingerprints are so unique and detailed that we can narrow down a sample to its origin," he said.

"Clues like the type of grapes used to the fermenting process can be answered by studying wine and comparing results to a trusted sample.

"We're still a long way off from having the technology affordable and therefore widely accessible but we're open to working with industry using facilities in the RMIT Food Research and Innovation Centre."

Led by Gill, RMIT researchers - including Professor Mark Osborn, Dr Daniel Dias and Dr Christopher Pillidge - are continuing development in this area, including investigating new ways to interpret the millions of data points extracted from food samples.

"As new tools become available, we'll have more power to inspect and interpret chemical data from food from many different angles, leading to more sustainable manufacturing," Gill said.

Researchers from Tokyo Medical and Dental University (TMDU) observe underdeveloped jaw cartilage in newborn rats exposed to periods of low oxygen

Tokyo, Japan - Breathing in adequate amounts of oxygen is critical for human life. However, certain disorders can cause individuals to go through periods where they are exposed to periodical low levels of oxygen, called intermittent hypoxia (IH). This is common in people who suffer from some sleep disorders like obstructive sleep apnea. Although we know IH can cause neurological development issues, it is not clear how it affects cartilage. Now, researchers at Tokyo Medical and Dental University (TMDU) have shown that IH can result in underdeveloped jaw cartilage in rats.

In an article published in Scientific Reports, researchers from TMDU revealed the inhibitory effects of IH on the growth of cells in the condylar cartilage of the mandible, which is the cartilage found at the rounded end of the jawbone. Previous work had primarily focused on how IH affects only bone growth.

Cartilage within different parts of the body often displays varying metabolic characteristics. Studies have shown that cartilage in the jaw has different growth patterns and gene expression profiles compared with cartilage in the limbs, for example. Because of this, the TMDU group became interested in how IH affects both mandibular cartilage and tibial (shinbone) cartilage. They compared both areas by examining growth of cartilage cells, called chondrocytes. The researchers also investigated the expression levels of specific genes in the cartilage cells that could help them recognize what phase of growth they were in.

"It is very important to understand more about the effects of intermittent hypoxia because it can lead to significant developmental issues," says lead author the study Kochakorn Lekvijittada. "It can even precede sudden infant death syndrome (SIDS) - a terrifying and tragic event that has sadly affected many families worldwide."

To address their questions, the researchers used newborn rats as a model system. They exposed one group of 1-week-old rats to air with normal amounts of oxygen, while another group of rats was exposed to alternating cycles of air with low oxygen levels. The researchers then investigated the effects on the rats' jaw and tibial cartilage growth.

"We observed inhibited growth of the cartilage in the rat jaws," describes Professor Takashi Ono, senior author. "Interestingly, the tibial cartilage was not affected by the hypoxic air exposure."

The authors also saw decreased expression levels of two genes called TGF-β and SOX9 in the jaw cartilage of the rats exposed to IH, while another gene named collagen X displayed increased expression.

"The gene expression patterns we observed in the jaw cartilage of the rats exposed to hypoxia were consistent with hypertrophy," says Dr. Lekvijittada. "This indicates that the jaw cartilage had restricted growth. We did not see these patterns in the tibial cartilage."

The findings of this study deliver novel insight into how being exposed to periods of low oxygen levels can affect jaw cartilage growth and development with potential applications in orthopedic medicine and diagnosis of temporomandibular disorders. This work also provides further understanding of how cartilage throughout the body differs depending on its location.

HIV infections are treated with antiviral drugs which effectively prevent the disease from developing. While pharmacological HIV therapy has advanced considerably, the virus cannot be entirely eliminated from the body with currently available drugs.

However, in roughly one-fifth of HIV patients the immune system does not recover as expected: the quantity of CD4 T cells, reflecting the status of the immune system, remains low even when the quantity of HI viruses in blood is suppressed to very low levels or below the measurement threshold. In such patients, indications of chronic immune activation, which erodes the immune system, can be detected.

In cooperation with the University of Erlangen-Nuremberg in Germany, researchers at the University of Helsinki have already shown that the Nef protein, a central factor associated with the HI virus, can continue low-level production in the patient's tissues for a long time even after viral multiplication is successfully suppressed. Important to this immunity-eroding activity are extracellular vesicles generated by Nef, circulating in blood and promoting chronic immune activation.

In a new study, Professor Kalle Saksela's research group has discovered an intracellular mechanism through which the chain of events associated with immune activation is initiated.

The study was published in the Journal of Virology.

"The new findings demonstrate that the Nef protein kicks off this harmful chain of events via cellular signalling: it activates protein kinases of the Src family, which leads to the activation of Raf and MAPK protein kinases. As these two protein kinases are activated, the production of extracellular vesicles, mediated by them, begins," Saksela explains.

Protein kinase inhibitors as a new treatment option?

Pharmaceutical agents that inhibit Src, Raf and MAPK protein kinases are already in clinical use, and the researchers at the University of Helsinki investigated their utility as well.

Studying the drugs in tissue cultures, they observed that it was possible to entirely prevent the production of inflammatory extracellular vesicles caused by the Nef protein using the same drug levels as in the current clinical use of protein kinase inhibitors.

"Our findings make it possible to explore novel therapies without delay in patients whose immunodeficiency is not reversed to a sufficient degree with current antiretroviral therapies. The repurposing of kinase inhibitors for treating HIV infection appears to be a very promising way of solving this significant medical challenge," Professor Saksela states.

In recent years, roughly 150 new HIV infections have been diagnosed in Finland annually. Throughout the 2000s, the number of new infections per year has remained under 200. In 2018 approximately 38 million people were estimated to be HIV positive, most of them in Africa.

A painful tradeoff between a number of infected and negative economic impact must be considered before deciding on the lockdown strategy within a city. As national economies continue to crumble, citizens wonder whether their governments did a good job at regulating the lockdown measures.

Russian city of St. Petersburg is at the frontlines of this ongoing war with Covid-19. To combat this situation effectively, Russian government allocated significant funds for the research. Results followed. Scientists from Peter the Great St.Petersburg Polytechnic University (SPbPU) modified the existing SIR class pandemic prediction model. Now it is better.

But why? What is the nature of this modification? Why is it necessary? And what kind of benefits does this modification provide?

Let's take a look:

Existing SIR (Susceptible - Infected - Recovered) class of models is widely known.

There are many modifications to the SIR model. One of them is SEIR (Susceptible - Exposed - Infected - Recovered)

The SEIR model was taken as a basis and then expanded to include another group: individuals in isolation or quarantine. That was the modification.

But why is this so important? To account for individuals in isolation or quarantine? Let's read the quote from the study:

"This modification of the SEIR model allows the number of susceptible individuals available for infection during modelling to be adjusted according to isolation scenarios (i.e., measures designed to prevent susceptible people from becoming infected). This means the model becomes more accurate, as the reduction of individuals in contact during the pandemic is objectively present in society. Moreover, the modification creates the possibility for scenario modelling. Scenario modelling involves assessing the epidemiological consequences of various strategies for countering the spread of an infectious disease in a given region."

This model has been tested on data from St.Petersburg.

A set of six experiments was sufficient to assess the impact of quarantine measures. The initial data for each experiment include isolated industries that indicate the timing of the introduction and lifting of isolation measures.

The results of this first group demonstrate that the dynamics of the virus' spread have a nonlinear dependence on the number of workers employed in the isolated sectors of the economy. For example, the isolation of three economic sectors, which make up approximately 42% of the total number of workers, reduces the peak number of infected people by 6.2 times and the total number of patients by 4.83 times. Isolation of six sectors of the economy, accounting for 80% of the total number of workers, reduces the peak number of infected people by 75 times and the total number of recovered individuals by 56 times".

The results of the second group show that the introduction of measures to isolate the economy and public life in the early stages of virus' spread can reduce the incidence of the disease and bring an earlier end to the pandemic. Conversely, the late introduction of isolation measures affects the dynamics of the disease's spread to a lesser extent. These results support assessments made by leading epidemiologists. These results indicate that the optimal disease-countering strategy is total isolation as early as possible.

This modified version of the SEIR model can be used to develop strategies for countering the spread of infectious diseases. It also enables researchers to assess the possible mortality in each case as a proportion of the total infected and recovered population.

The article develops a methodological apparatus of a SIR-class model for practical use in decision-making by regional leaders.

Tohoku University scientists and their colleagues in Germany have revealed that a first-time exposure to only a brief period of brain hyperactivity resulted in an acute breakdown of the inter-cellular network of glial cells. Pharmacological intervention of the glial plasticity may provide a new preventative strategy for fighting epilepsy.

The findings were detailed in the Journal of Neuroscience.

Epilepsy is a disorder characterized by neuronal hyper-excitation and a progression of seizures with each episode. Anti-epileptic drugs are mostly aimed at suppressing hyperactivity, but approximately 30% of patients worldwide show drug-resistance.

Half of the brain is occupied by non-neuronal glial cells. Astrocytes are star-shaped glial cells that are connected to each other via gap junctions. Neuronal excitation leads to potassium extrusion from neurons. The excess potassium is picked up by astrocytes and diluted in the astrocyte network. Efficacy of the potassium clearance can affect neuronal signal processing.

"Astrocytes have a strong control over neuronal activity," says professor Ko Matsui of the Super-network Brain Physiology lab at Tohoku University, who led the research. "Plasticity of the neuronal network underlies learning and memory but apparently astrocyte function is also susceptible to plastic change."

A collaborative research group led by Matsui, doctoral student Mariko Onodera and researchers at Heinrich Heine University Düsseldorf, studied the plastic change of astrocytes associated with epileptogenesis in mice.

In response to hyperactivity of the surrounding neurons, Na+/HCO3- co-transporter (NBC) in astrocytes was activated. The resulting intracellular alkalization led to gap junction uncoupling and impairment of prompt potassium clearance. Pharmacological blockade of the NBC suppressed the plastic change of the astrocyte network and prevented intensification of epileptiform activity.

"Astrocytes play a crucial role in taking control of neuronal activity in healthy brains as well, said Matsui. "Our research reveals the presence of glial plasticity and suggests a future therapeutic strategy can be aimed to control the glial function for treating disease."

An impressive body of evidence published this week reveals the answer to a mystery that has puzzled plant scientists for more than 30 years: the role of the molecule suberin in the leaves of some of our most productive crops. This discovery could be the key to engineering better crops and ensuring future food security.

Highly productive crops such as sugarcane, sorghum and maize belong to the type of plants that use the more efficient C4 photosynthetic pathway to transform water, sunlight and carbon dioxide (CO2) into sugars.

Scientists have known for a long time that one of key factors that makes C4 photosynthesis more efficient is that they have the capacity to enclose CO2 inside a gas tight compartment in the leaf tissue, making it easier for the inefficient photosynthetic enzyme Rubisco to fix carbon.
"The big question we haven't been able to answer until now is what makes this compartment gas tight so CO2 can't escape?" says lead author Dr Florence Danila, from the ARC Centre of Excellence for Translational Photosynthesis (CoETP) at the Australian National University (ANU).

"Our research provides several pieces of evidence about the responsibility of suberin on making the leaf cells of C4 plants, gas tight. Suberin forms a layer that keeps CO2 gas inside a layer of cells called the bundle sheath. We have grown mutant plants that don't develop this layer and we have seen the deleterious effect this mutation has in their growth and in their capacity to photosynthesise," says Dr Danila, who works at ANU as part of the international C4 Rice Project, led by Oxford University.

This discovery is the result of many years of work, a bit of serendipity and access to modern techniques that were not available until recently, including faster and cheaper genome mapping, high throughput phenotyping, electron microscopy and gas exchange measures.

"We have known for a long time that suberin is in the bundle sheath cells of the C4 plants leaves. However, we didn't have the experimental evidence to prove its essential role for C4 photosynthesis. Now, for the first time, we have been able to see clearly under the microscope, the anatomical differences between plants with and without suberin. The key element in this discovery is that we found a mutant population of green foxtail millet (Setaria viridis) that didn't have the gene that produces suberin," says CoETP's Deputy Director Professor Susanne von Caemmerer, one of the co-authors of this study.

This elusive mutant population was generated in the International Rice Research Institute (IRRI) by screening hundreds of plants under low CO2 conditions and then selecting those plants that didn't perform well.

"Using high throughput screening, we identified only three mutants with impaired photosynthetic capacity. We sent the seeds to ANU in Canberra and they grew and analysed them using the electron microscope and gas exchange techniques. To our surprise, one of these mutants was the one that lacked suberin, says Dr Rob Coe, who was in charge of the screening process at IRRI.

Centre Director and co-author of the paper Bob Furbank says that "this is a very exciting discovery, one of the last mechanistic pieces of the C4 photosynthesis puzzle, as Hal Hatch, the discoverer of the C4 pathway noted some time ago".

"It shows that science discoveries can take a long time to be solved and that the recipe for eureka moments like this are the collaborative work of several experts combined with modern technologies, plus a pinch of serendipity. It seems that all the stars were aligned this time for us, but it was certainly a hard nut to crack," he says.

Dr Danila says that the team's next steps involve applying their discovery and new developed methodologies to projects like the C4 rice project that aims to convert rice (a C3 photosynthesis crop) into the more productive C4 path.

"We will also focus on another unsolved mystery: the case of a group of grasses which use C4 photosynthesis but don't have suberin," she says.

A University of Melbourne led study has established how plants use their metabolism to tell time and know when to grow - a discovery that could help leverage growing crops in different environments, including different seasons, different latitudes or even in artificial environments and vertical gardens.

Published in the PNAS journal, Superoxide is promoted by sucrose and affects amplitude of circadian rhythms in the evening, details how plants use their metabolism to sense time at dusk and help conserve energy produced from sunlight during the day.

Lead researcher Dr Mike Haydon, from the School of BioSciences, said while plants don't sleep as humans do, their metabolism is adjusted during the night to conserve energy for the big day ahead of making their own food using energy from sunlight, or photosynthesis.

"Getting the timing of this daily cycle of metabolism right is really important because getting it wrong is detrimental to growth and survival," Dr Haydon said. "Plants can't stumble to the fridge in the middle of the night if they get hungry so they have to predict the length of the night so there's enough energy to last until sunrise; a bit like setting an alarm clock."

Dr Haydon and collaborators had earlier shown that the accumulation of sugars produced from photosynthesis give the plant important information about the amount of sugar generated in the morning and sends signals to what's known as the circadian clock, to adjust its pace.

"We have now found that a different metabolic signal, called superoxide, acts at dusk and changes the activity of circadian clock genes in the evening," said Dr Haydon. "We also found that this signal affects plant growth. We think this signal could be providing information to the plant about metabolic activity as the sun sets."

Researchers hope the study will be invaluable in the world producing more food, more reliably.

"As we strive to produce more food for the increasing global population in the face of changing climate, we may need to grow crops in different environments such as different seasons, different latitudes or even in artificial environments like vertical gardens," Dr Haydon said.

"Understanding how plants optimise rhythms of metabolism could be useful information to allow us to fine-tune their circadian clocks to suit these conditions and maximise future yields."

Research from the University of Kent has led to the development of the MeshCODE theory, a revolutionary new theory for understanding brain and memory function. This discovery may be the beginning of a new understanding of brain function and in treating brain diseases such as Alzheimer's.

In a paper published by Frontiers in Molecular Neuroscience, Dr Ben Goult from Kent's School of Biosciences describes how his new theory views the brain as an organic supercomputer running a complex binary code with neuronal cells working as a mechanical computer. He explains how a vast network of information-storing memory molecules operating as switches is built into each and every synapse of the brain, representing a complex binary code. This identifies a physical location for data storage in the brain and suggests memories are written in the shape of molecules in the synaptic scaffolds.

The theory is based on the discovery of protein molecules, known as talin, containing "switch-like" domains that change shape in response to pressures in mechanical force by the cell. These switches have two stable states, 0 and 1, and this pattern of binary information stored in each molecule is dependent on previous input, similar to the Save History function in a computer. The information stored in this binary format can be updated by small changes in force generated by the cell's cytoskeleton.

In the brain, electrochemical signalling between trillions of neurones occurs between synapses, each of which contains a scaffold of the talin molecules. Once assumed to be structural, this research suggests that the meshwork of talin proteins actually represent an array of binary switches with the potential to store information and encode memory.

This mechanical coding would run continuously in every neuron and extend into all cells, ultimately amounting to a machine code coordinating the entire organism. From birth, the life experiences and environmental conditions of an animal could be written into this code, creating a constantly updated, mathematical representation of its unique life.

Dr Goult, a reader in biochemistry, said: 'This research shows that in many ways the brain resembles the early mechanical computers of Charles Babbage and his Analytical Engine. Here, the cytoskeleton serves as the levers and gears that coordinate the computation in the cell in response to chemical and electrical signalling. Like those early computation models, this discovery may be the beginning of a new understanding of brain function and in treating brain diseases.'

New research from the University of Kent reveals social cohesion with immigration is best ensured through childhood exposure to diversity in local neighbourhoods, leading to acceptance of other groups.

The research, which is published in Oxford Economic Papers, builds on the Nobel Laureate economist Thomas Schelling's Model of Segregation, which showed that a slight preference by individuals and families towards their own groups can eventually result in complete segregation of communities.

Shedding new light on this issue, researchers from Kent's School of Economics have introduced the theory that adaptability to a diverse social environment depends on greater exposure to diversity in childhood years. Following this increased acceptance of other social groups in a community, social diversity and cohesion is then sustainable.

A model of immigration based on this theory shows that fast-paced immigration into a community reduces social cohesion and increases social segregation, which explains the recent evolution of social diversity within UK communities and social attitudes towards other groups. The study also shows a medium pace of immigration is more effective in establishing acceptance of diversity within communities, leading to greater community cohesion over time.

Dr Zaki Wahhaj, Reader in Economics at the University of Kent and joint author of the paper, said: 'For a long time there has been a blind spot in debates around immigration and the social integration of minority groups: namely, that sustaining social cohesion requires not only adaption by immigrants but also a shift in how majority groups see themselves. We discovered that bringing insights from psychology - that childhood experiences are key to forming identity - easily overturns the predictions of standard economic models for studying social segregation.'