Culture

More than ten years ago, large geometric earthworks found in the southwestern parts of the Amazon, called geoglyphs, were reported in the global scientific news. A pre-colonial civilization unknown to scholars that built geometric ceremonial centers and sophisticated road systems. This civilization flourished in the rainforest area 2,000 years ago. The discovery radically altered the prevailing notion of the pristine Amazon rainforest. The research of an interdisciplinary Finnish-Brazilian team continues in the region with the support of the Academy of Finland. Recent findings show that large ancient construction projects not only shaped the landscape, but civilization has also impacted the diverse construction of rainforest.

The research team's latest article "Domestication in Motion" has been published in the journal Environmental Archeology last week. The article shows that in addition to the cultivation of manioc, maize and squash, the protection, care and planting of several trees were important for the food supply of the region's Indigenous peoples, says research director Professor Martti Pärssinen. In particular, Brazilian nut and palm trees with protein-rich fruits are common in samples from geoglyphic sites. They show the pre-colonial diet of the geoglyphic ceremonial sites.

The article also describes how tree domestication was not a linear process in Amazon conditions, as wild forms of plants could also be protected. During the archaeological excavations wild and domesticated forms of peach palm fruit were found, among other plants. On the other hand, especially Brazilian nut trees as well as many palm trees, which are vital for both their fruits and palm kernels, were domesticated in the rainforest area for human consumption. Their fruits are clearly larger than they were 2,000 years ago.

A unlinear process of domestication is evident, as both wild and domesticated peach palm trees are still well known by Indigenous peoples in the state of Acre, and the latter have spread to a very large area across the Amazon, says Pirjo Kristiina Virtanen, assistant professor involved in the project.

Human impact on the Amazon rainforest stand has been significant, and therefore there is no such thing as virgin rainforest. On the other hand, the study shows that Indigenous peoples of the Amazon have been able to use their environment in a sustainable way by domesticating certain plants while protecting and respecting it. There is no indication that large areas of forest would have been deforested.

These new findings argue against the idealistic notion of the pristine Amazon rainforest. At the same time, however, it highlights how Indigenous peoples utilize wild plants while domesticating certain plants for humans' use. The relationship between the peoples of the Amazon and forest has been proved sustainable. It should be explored further and lessons could be learned from this.

The authors of the article are from the University of Helsinki. Martti Pärssinen, Professor Emeritus leads the project and Pirjo Kristiina Virtanen, Assistant Professor of Indigenous Studies, has worked with the Indigenous peoples of the region. In addition to them, the authors were Brazilian palm researcher Evandro Ferreira and paleoecologist Alceu Ranzi from the Federal University of Acre. The Finnish Cultural and Academic Institute in Madrid has also contributed to the project. In Brazil the research was authorised by Instituto do Patrimônio Histórico e Artístico Nacional (IPHAN) and Fundação Nacional do Índio (FUNAI).

The blood circulatory system serves as critical infrastructure for mass transportation of nutrients and facilitates the exchange of gaseous and waste products from organs in the human body. These blood vessels are subjected to constant exposure to the hydrodynamic pressure of blood flow, as well as the contracting and relaxing rhythm exerted by tissues surrounding it. The exposure to these stimuli can trigger a cascade of cellular responses that may give rise to adverse conditions such as thrombosis and inflammation in blood vessels.

These cellular responses to events are known as mechanotransduction - the process of converting mechanical signals into chemical signals in the body. Although researchers have managed to engineer disease models that mimic various impairments in blood vessels, the ability to incorporate simultaneous shear stress from blood flow and stretch stress was still deemed as challenging to replicate.

Researchers from Keio University (Keio U) Onoe Research Group collaborated with Singapore University of Technology and Design's (SUTD) Soft Fluidics Lab to develop and fabricate an extracellular matrix (ECM)-based microchannel that enables to provide mechanical stimuli due to perfusion and stretching simultaneously (refer to image). This straightforward method allowed the researchers to make a complex network of microchannels in an ECM that resembled human tissues by sacrificial molding.

In this approach, the mold was first patterned with bifurcations and cascading dimensions as low as 0.2 mm in width. A commercially and ubiquitously available fused deposition modeling (FDM) 3D printer was used to print the sacrificial mold made with polyvinyl alcohol (PVA). Unlike a well-establish method such as replica molding where multiple steps of assembly and alignment were required to create microchannel with 3D geometry, sacrificial molding enabled the rapid fabrication of microchannels in various matrices. The mold was embedded entirely in an ECM (gelatin), cured with transglutaminase; sealing, alignment, or stacking were not necessary when making the platform for blood vessels and surrounding tissue.

"Since the PVA mold is removable in water, the process of fabrication was entirely completed using only water. This is important to ensure the biocompatibility of the fabricated microchannels," said Jason Goh, a Ph.D. scholar at SUTD.

"Sacrificial molding of a fused deposition modeling 3D-printed mold offers wide freedom of design and potentiates the fabrication of more physiological relevant platform," added Assistant Professor Michinao Hashimoto from SUTD.

Human endothelial cells were readily cultured on the surface of the microchannel to form a tube mimicking blood vessels. The hallmark behavior of blood vessels, such as its pulsatile flow, was successfully achieved under conditions of perfusion and stretch. This blood vessel platform served to broaden the spectrum of applicability of current vascular in vitro models to investigate pathological conditions in a more physiologically relevant manner.

"We successfully demonstrated to engineer substitutes for blood vessels with sufficient mechanical strength to withstand the applied fluid pressure and stretching present in the human body. The platform will be useful to understand the mechanisms of vascular diseases," said Azusa Shimizu, the lead author and an MSc student, and Associate Professor Hiroaki Onoe from Keio U, Japan.

The research work has been published and featured prominently in the inside cover of Lab on a chip, the top journal covering original work related to the miniaturization below the microscale and at the interface between technological advancements and impactful applications. Azusa Shimizu (Keio U) collaborated with Jason Goh (SUTD) and Shun Itai (Keio U). Other senior researchers of the project include Dr. Shigenori Miura from the University of Tokyo.

It's not often that scientists are able to find tuff in continental sedimentation, but this was accomplished in the PreUrals region by Kazan Federal University, Borisyak Institute of Paleontology, and Institute of Geology (the latter two are parts of the Russian Academy of Sciences). This was a first such finding on the territory of European Russia. Radioisotopic analysis was conducted by Boise State University.

"We calculated the precise age of the upper layers of the continental formation of European Russia. The age is 253.95 million years, and this helped us to directly compare sea and continental sedimentation, something that would be impossible with the sole use of paleontological methods. This is a first opportunity to directly compare fauna associations of terrestrial vertebrates in Russia, Southern Africa, Greenland, and India. Thus, we can determine the length of thaws and glaciations in European Russia in late Permian," says co-author Vladimir Silantiev, Chair of the Department of Paleontology and Stratigraphy at Kazan Federal University.

Tuff includes microscopic particles of zircon, which makes it possible to determine the absolute age of rocks. After seven years of work, the key finding was made near the Vetluga River in Northern Russia. Volcanic tuff from thousands of kilometers away ended up here. Continental platforms are usually not conducive to preserving such material for millions of years because of intense geological processes, but in this case, the researchers were in luck.

As the "king of beasts," majestic lions have been used as a symbol of courage, nobility and strength by rulers for over 6000 years. A lion became the symbol of a Norwegian king at least as early as 1280. It still stands proudly on Norway's Coat of Arms.

Wild lions have likely never made their way to Norway, but European cave lions were once found as far north as Denmark.

Lions were once far more widespread than they are now, with several subspecies of lions dividing the world between them. They were found in much of Europe and Asia including the Middle East, in Africa, North America and maybe South America.

Today, the lion is considered a vulnerable species, and is found only in relatively isolated pockets of Africa and - just barely still - in India.

Filling in the lions' family tree

Experts disagree on how many subspecies exist now and have previously existed, and presumably there is significant overlap among several of them. We need to know this information to save the lions.

"We wanted to find out more about the relationships between the different groups, or populations, of lions," says Michael D. Martin at the Norwegian University of Science and Technology's (NTNU) University Museum's Department of Natural History.

An international research group has helped expand our understanding of the lion species' family tree. The results were recently presented in PNAS, the Proceedings of the National Academy of Sciences of the United States of America.

Associate Professor Martin is among the contributors. The last author is Professor Tom Gilbert from the same department. He is also head of the Centre for Evolutionary Hologenomics at the University of Copenhagen.

Tackling the whole DNA

Previously, the cave lion Panthera leo spelaea was found across much of Eurasia and as far as Alaska and Canada.

But cave lions died out 13 000 years ago, perhaps partly due to humans, although palaeontologists suspect that climate change played a major role. The American lion P. leo atrox suffered the same fate.

The researchers wanted to find answers to several questions.

How closely related were cave lions to today's lions?

When did cave lions and today's lions diverge?

Are some of today's lion populations more closely related to cave lions than others?

How much genetic diversity do lions have today compared to in the past?

Several groups have previously investigated mitochondrial DNA (mtDNA) when they were studying the relationships between different populations of lions. (See fact box.)

"But mtDNA is only a small part of the overall genetic material. Our group looked at all the DNA to get a more complete picture," says Gilbert.

Little interbreeding by cave lions

The research team examined two cave lions, from Siberia and Canada's Yukon. They also looked at 12 lions from populations that died out in historical times in Africa and the Middle East. In addition, they examined six lions from populations that are still extant in Africa and India.

The geographical spread of these lions corresponds very roughly to the area lions once inhabited, and where they still exist today.

"The cave lions don't appear to have mixed much with the other subspecies. We find no evidence of hybridization between the cave lions and the other groups of lions," says Gilbert.

The studies also indicate that cave lions and other lions most likely diverged about 500 000 years ago. This is in line with some previous findings, while others believe that they probably parted ways much earlier.

Two main branches

Not only the cave lions are distinct from other lions. Modern lions also show two main branches that may have diverged some 70 000 years ago.

"A northern branch includes Asian, North African and West African lions. A southern African branch includes southern, eastern and South African lions," says Martin.

This division is the same as other research groups have found by examining mitochondrial DNA (mtDNA) - up to a point. But the new study differs in several areas as well.

Studies of mtDNA have previously grouped central African lions with the northern branch, but studies of the entire DNA show that they might belong to the southern one instead.

Could help the Barbary lions

Furthermore, the North African lions, which are at least extinct in the wild, are probably more closely related to the West African lions than to the Asian lion lineage, which many scientists have believed up to now.

"This is important to know for people who may want to bring back the North African lions," says Martin.

The North African Barbary lions disappeared from the wild in the 1960s, but captive specimens may be Barbary lions, at least in part.

If these captive individuals ever need new external gene supplements to prevent inbreeding, it would probably be best to use West African lions rather than Asian ones.

Important to know what we have

Perhaps it seems a bit strange to some that several research groups are spending so much time figuring out the relationships between the different lions in the world.

"The work isn't interesting only for us geneticists and natural historians, although that's exciting enough. It's also important for people who want to conserve our lions and give them a fair chance to survive as a species outside captivity," says Gilbert.

As many as one million lions might have lived in the wild as recently as 1950. Today, a common estimate is between 20 000 and 30 000. Only 600 of the Indian lions are left.

Human activity is the main cause of the decline in most places, either directly by humans killing animals or indirectly by our species impacting their habitats.

"Some people have claimed that the Indian lions are actually African lions that were released into the wild in India and that it's therefore not as valuable to preserve them. But we've found that the Indian lions are so genetically different from the African lions that this claim can't be true," says Gilbert.

Danger of inbreeding

The research group is also finding less genetic diversity between the lions today than was found a few decades ago. This may be especially true of the geographically isolated Indian lions.

"We have fewer lions than we used to, and groups of lions are actually isolated from other groups, often due to human activity. That increases the risk of inbreeding," says Martin.

Inbreeding, which results in lions being more genetically similar, may mean that the population is more susceptible to various diseases and may not be able to reproduce. Of course, this is important to know for anyone who is involved with preserving the lions.

According to senior researcher at the Universitat Oberta de Catalunya's Internet Interdisciplinary Institute (IN3) Gender and ICT (GenTIC) research group, Milagros Sáinz, "In those cases where families have very sexist attitudes in relation to education and life, their opinions in terms of academic and other skills which boys and girls are ideally supposed to have may hold even more weight."

Despite the current lockdown being a temporary event, the researcher suggests that such circumstances may influence the decisions being made by young people with regard to their educational path in terms of their choice of courses for post-compulsory secondary or university education.

"There is a risk that young people, especially those from certain socio-economic and cultural backgrounds, will be more likely to be swayed by the opinions and experiences of their parents than they would have been prior to the health crisis," says Sáinz, who went on to add that, "They are not socializing with others, such as teachers or members of their peer groups in the same way as they were before quarantine."

In a study published in the International Journal of Social Psychology, the researcher with José Luis Martínez and Julio Meneses, also from the UOC, analysed the differences corresponding to gender in the response mechanisms of secondary school students with regard to scenarios related to academic sexism. The researchers explain that "girls are particularly likely to encounter this kind of situation, as they are more frequently faced with sexist attitudes about their abilities in science, technology, engineering and mathematics (STEM) subjects than boys."

According to the study, students whose parents had completed intermediate or higher level academic studies showed a greater predisposition to actively confronting sexist situations. "Interestingly, we observed that boys tend to use avoidance in response to scenarios of academic sexism, whereas girls are more likely to confront them or seek help from people in authority, such as teachers or family members, when it comes to this type of situation," the expert pointed out.

Boys are also affected by sexism

The study sampled 954 first-year baccalaureate students across ten schools in the metropolitan areas of Madrid and Barcelona. Sixty per cent of the students described their parents' level of academic achievement as intermediate, while 30% said that it was high and the final 10% reported a low level of education. In terms of origin, 80% of the student's parents were born in Spain.

Students were asked to complete a questionnaire in which they were presented with a series of different scenarios involving sexist attitudes towards their academic abilities and they had to state whether they would respond by: confronting the situation, asking for help or avoidance.

The students also had to indicate to what extent they agreed with five sexist statements about the academic abilities of boys and girls. In terms of their own personal experience, they also had to say whether anyone around them had ever made discouraging remarks about their abilities in STEM fields, such as mathematics, technology and physics (in the case of girls), or in languages and biology (in the case of boys).

In the words of Milagros Sáinz, "Our society tends to undervalue women's abilities with regard to highly prestigious and socially valued subjects and fields, such as science and technology. Boys, however, are used to their skills being valued above those of girls, which is also an example of sexism, albeit positive in this case, as it works in their favour."

According to the expert, this type of sexism does not mean that all boys have a greater affinity for those subject areas and they also feel frustrated and suffer its negative effects because many "do not comply with that ideal of masculinity".

The influence of parental academic achievement

In addition to gender being influential in determining the way young people tackle academic discrimination, the study also emphasizes an impact corresponding to levels of parental education.

As pointed out by Sáinz, "Gender explains the different ways of coping with academic sexism per se but the educational level of parents helps us understand the degree to which groups of students are predisposed to actively respond to such situations."

Girls whose parents had completed post-compulsory secondary education or university studies tended to respond to sexist scenarios by confronting the relevant person, whereas in boys with a similar family background, the response was often avoidance.

The study also reveals that, in some cases, the students themselves are not aware of having personally witnessed or experienced this kind of discrimination. "Girls are often exposed to academic sexism that questions their technological competence but they perceive this as being based on their own personal lack of ability and rule out pursuing it as a result," explained Sáinz, adding that, "They don't realize that this is a stereotypical belief applied to women based solely on the fact that they are women." The opposite is true for boys: their decisions and behaviours are also strongly conditioned by social and cultural expectations related to masculinity.

To prevent these kinds of imbalances, the expert stressed the importance of educating boys and girls on issues related to equality and how to deal with different academic or other types of sexist scenario; a programme that would also need to be extended to teachers and families.

People in what is now Washington State were smoking Rhus glabra, a plant commonly known as smooth sumac, more than 1,400 years ago.

The discovery, made by a team of Washington State University researchers, marks the first-time scientists have identified residue from a non-tobacco plant in an archeological pipe.

Unearthed in central Washington, the Native American pipe also contained residue from N. quadrivalvis, a species of tobacco not currently grown in the region but that is thought to have been widely cultivated in the past. Until now, the use of specific smoking plant mixtures by ancient people in the American Northwest had only been speculated about.

"Smoking often played a religious or ceremonial role for Native American tribes and our research shows these specific plants were important to these communities in the past," said Korey Brownstein, a former WSU Ph.D. student now at the University of Chicago and lead author of a study on the research in the journal Frontiers in Molecular Biosciences. "We think the Rhus glabra may have been mixed with tobacco for its medicinal qualities and to improve the flavor of smoke."

The discovery was made possible by a new metabolomics-based analysis method that can detect thousands of plant compounds or metabolites in residue collected from pipes, bowls and other archeological artifacts. The compounds can then be used to identify which plants were smoked or consumed.

"Not only does it tell you, yes, you found the plant you're interested in, but it also can tell you what else was being smoked," said David Gang, a professor in WSU's Institute of Biological Chemistry and a co-author of the study. "It wouldn't be hyperbole to say that this technology represents a new frontier in archaeo-chemistry."

Previously, the identification of ancient plant residues relied on the detection of a limited number of biomarkers, such as nicotine, anabasine, cotinine and caffeine. Gang said the issue with this approach is while the presence of a biomarker like nicotine shows tobacco was smoked it doesn't distinguish which species it was.

"Also, if you are only looking for a few specific biomarkers, you aren't going to be able to tell what else was consumed in the artifact," Gang said.

In addition to identifying the first non-tobacco plant smoked in an archaeological pipe, the WSU researchers' work also helps elucidate the complex evolution of tobacco trade in the American Northwest.

Analysis of a second pipe that was used by people living in Central Washington after Euro-American contact revealed the presence of a different tobacco species, N. rustica, which was grown by native peoples on the east coast of what is now the United States.

"Our findings show Native American communities interacted widely with one another within and between ecological regions, including the trade of tobacco seeds and materials," said Shannon Tushingham, an assistant professor of anthropology at WSU and co-author of the study. "The research also casts doubt on the commonly held view that trade tobacco grown by Europeans overtook the use of natively-grown smoke plants after Euro-American contact."

Moving forward, the WSU researchers' work could ultimately help scientists studying ancient societies in the Americas and elsewhere around the globe identify which plant species ancient people were consuming, providing important information about the evolution of drug use and similar plant-human dynamics.

Closer to home, the WSU team is also putting their work to use helping confirm connections between ancient plant management practices from before the arrival of Western settlers with cultural traditions of modern indigenous communities such as the Nez Perce.. The researchers shared their work with members of the tribe who also used some of the seeds from the study to grow some of the pre-contact tobacco. The smoking of tobacco is a sacred tradition for Native American groups including the Nez Perce, Colville and other northwest Tribes and before now it was impossible to tell which kind of tobacco their ancestors smoked.

"We took over an entire greenhouse to grow these plants and collected millions of seeds so that the Nez Perce people could reintroduce these native plants back onto their land," Brownstein said. "I think these kinds of projects are so important because they help build trust between us and tribal communities and show that we can work together to make discoveries."

DURHAM, N.C. -- The thin, slippery layer of cartilage between the bones in the knee is magical stuff: strong enough to withstand a person's weight, but soft and supple enough to cushion the joint against impact, over decades of repeat use. That combination of soft-yet-strong has been hard to reproduce in the lab. But now, Duke University researchers say they've created an experimental gel that's the first to match the strength and durability of the real thing.

The material may look like a distant cousin of Jell-O -- which it is -- but it's incredibly strong. It's 60% water, but a single quarter-sized disc can bear the weight of a 100-pound kettlebell without tearing or losing its shape.

Its developers say it's the first hydrogel -- materials made of water-absorbing polymers -- capable of withstanding tugging and heavy loads as well as human cartilage, without wearing out over time.

Led by Duke chemistry and materials scientists Ben Wiley and Ken Gall, the research could one day offer people with knee troubles a replacement for damaged cartilage, and an alternative to the 600,000 knee replacement surgeries performed in the U.S. each year.

A smooth rubbery tissue that covers the ends of bones and enables them to glide smoothly against each other, cartilage helps absorb a huge amount of force with every step -- typically between two and three times your body weight.

However, cartilage also has limited ability to heal and repair itself. Once worn by age, overuse or trauma it's difficult to treat, said Gall, a professor of mechanical engineering and materials science at Duke.

For patients who want to avoid or postpone a knee replacement that may only last 20 years, artificial cartilage can help. Hydrogels have been explored for use as a cartilage substitute since the 1970s and are used in soft contact lenses and disposable diapers. Researchers are attracted to these materials because of their slippery, shock-absorbing properties and because they don't harm nearby cells. But until now they've proven too weak to be used in load-bearing joints like the knee.

The Duke team set out to change that. "We set out to make the first hydrogel that has the mechanical properties of cartilage," said Wiley, a chemistry professor at Duke.

The new hydrogel consists of two intertwined polymer networks: one made of stretchy spaghetti-like strands and the other more rigid and basketlike, with negative charges along their length. These are reinforced with a third ingredient, a meshwork of cellulose fibers.

When the gel is stretched, the cellulose fibers resist pulling and help hold the material together. And when it is squeezed, the negative charges along the rigid polymer chains repel each other and stick to water, helping it spring back to its original shape.

"Only this combination of all three components is both flexible and stiff and therefore strong," said co-author Feichen Yang, who earned a chemistry PhD in Wiley's lab.

When the researchers compared the resulting material to other hydrogels, theirs was the only one that was as strong as cartilage under both squishing and stretching.

In one experiment, the team subjected it to 100,000 cycles of repeat pulling, and the material held up just as well as porous titanium used for bone implants, "which exceeded our initial expectations," said co-author William Koshut, a PhD student in the Gall lab.

They also rubbed the new material against natural cartilage a million times. They found that its smooth, slippery self-lubricating surface is as wear-resistant as the real thing and four times more wear-resistant than synthetic cartilage implants currently FDA-approved for use in the big toe.

Moving the material from the lab to the clinic would take another three years at least, Wiley said. Initial safety tests suggest the material is nontoxic to lab-grown cells. The next step is to design an implant that they can test in sheep.

But the team says eventually the research could offer new options for people with knee pain, and get them back to doing the things they love without the long recovery times and limited lifetime associated with cartilage repair or knee replacement surgery.

The study, published recently in Circulation Research and led by a team from King's College London, has investigated how nitrogen dioxide can impact the cardiovascular system.

The study examined the blood chemistry and cardiovascular changes of 12 healthy volunteers. They sat next to a domestic gas cooker for ninety minutes followed by ninety minutes with normal background nitrogen levels. On another occasion, the volunteers were exposed to normal background nitrogen dioxide levels for three hours.

The period next to a gas cooker increased nitrogen dioxide levels in the air 10-fold and subsequently lowered blood pressure by 5 mm Hg from 45 minutes onwards. The study also found that blood levels of the substance nitrite increased by 15% after 15 minutes.

Previous studies have shown nitrite, which can be converted from dietary nitrate following the ingestion of green leafy vegetables and beetroot, can lower blood pressure. This study suggests nitrite can also be made when the body processes nitrogen dioxide and makes a link between previous research focusing on dietary nitrate and studies of inhalation of nitrogen dioxide for the first time.

Air pollution contributes to illness and death in the general population, but it is a complex mixture of airborne particles and gases, including nitrogen dioxide. Working out the individual effects of each is challenging and there has been a running debate about how to distinguish between the independent effects of nitrogen dioxide and respirable particles in the air.

While the evidence linking nitrogen dioxide to a worsening of symptoms in respiratory disease is well established, its short-term impact on the heart and circulation is less clear. Notably, people with domestic gas appliances or people working in kitchens with gas cookers may be exposed to higher levels of nitrogen dioxide, but with less particulate matter, than that found on the street.

This unique study helps to shed light on some of the rapid effects of nitrogen dioxide on the heart and circulation. Looking at previous air pollution studies, it had been unclear whether the nitrite in the blood came from nitrogen dioxide or from particulate matter causing inflammation and generation of nitric oxide, which is converted to nitrite. This study suggests that it is the nitrogen dioxide that causes nitrite to be formed in the blood.

Crucially, while this effect of short-term exposure to nitrogen dioxide in healthy volunteers may be beneficial, there are other studies of adverse effects of long-term exposure to nitrogen dioxide, and on adverse effects of short-term exposure in asthmatics.

Further research will confirm these findings in larger studies and examine the effects on a more varied cohort.

Dr Andrew Webb, Clinical Senior Lecturer at King's College London, said: "High blood pressure is the biggest single contributor to deaths around the world. Therefore, if exposure to nitrogen dioxide from gas cookers contributes to lowering blood pressure, this could be beneficial per se, and in the context of general air pollution may partially offset the adverse cardiovascular effects of short-term exposures to elevated particulate matter concentrations.

"The mechanism by which nitrogen dioxide lowers blood pressure appears to be through linking into the same pathway as dietary nitrate (found in green leafy vegetables and beetroot): both result in an increase in blood nitrite levels. Therefore, it is not just what you eat, but how you cook it that matters."

Marina Domracheva and Sofya Kulikova, researchers from HSE University's campus in Perm, have discovered a new approach to analyse the perceived similarity of food products, based on electroencephalography (EEG) signals. They note that the power of gamma oscillations can reflect similarities in a cross-modal approach. Their paper was published in the journal Food Quality and Preference.

The most common tools used to understand people's perception of food products are hall tests, surveys and observations. There is a general assumption that consumers can evaluate and express their real preferences, but it is not uncommon when a consumer's expressed opinion of the product does not comply with their behaviour. In addition, such research can be costly for companies.

Neuromarketing may help to eliminate these troubles. To analyse consumers' preferences, neuromarketing specialists can apply neuroimaging technologies, such as magnetic resonance imaging (MRI) and electroencephalography (EEG).

The researchers from HSE University used a cross-modal approach to study how food product similarity is assessed. This approach is based on the integration of senses from different modalities (taste, smell, and visual appearance) in an integral image of an object. For this experiment, 18 participants tasted multi-cereal candies, and then looked at images of similar objects, such as cookies, cereal bars or oatmeal. The respondents evaluated the similarities of each of these products with the candy they had just tried. While this was happening, their brain activity was recorded using EEG.

Two EEG-based metrics were considered as a potential measure of product similarity: the power of induced gamma oscillations during a 400-600 ms period after the presentation of a visual stimulus and an amplitude of N400 evoked response potentials.

In EEG-registered brain activity, oscillations of varying frequency and amplitude can be detected, which are related to various psychological processes. Gamma oscillations have frequency over 30 Hz and are detected when the brain is solving tasks that require focusing the attention and exchanging the information between different brain areas.

Evoked gamma oscillation with a power of 30-80 Hz is thought to ensure the distributed processing of information in various areas of the brain to form a common consistent perception of a given object on the basis of its various characteristics - visual, audial, and taste. For example, if the vocalization of an animal is congruent with the animal's image, the power of the evoked gamma oscillations grows. The researchers also assumed that a similar effect may be observed when food products are compared. And indeed, when the respondents looked at products that were similar to multi-cereal candies (such as cereal bars), the power of the gamma oscillations was at their highest.

'The amplitude of the N400-like negative difference component is registered by EEG when we see a minor error or incongruency: e.g, between a taste feeling and the visual perception of the product,' says Sofya Kulikova. 'When an experiment participant tasted the candy and then viewed an image of broccoli or fried potatoes, the amplitude was at its highest.'

The N400-like component is a wave that appears on the EEG at about 400 ms after the onset of the stimulus and has a negative amplitude polarity.

It turned out that both approaches are reasonable, but the N400-like component amplitude displayed a high variability among the respondents. Therefore, in a perceived similarity assessment, it is better to rely on the power of gamma oscillations.

The approach discovered by the researchers may be applied to neuromarketing studies of food taste perception. In particular, this method can be a useful tool to study the perception of new innovative products manufactured with the use of innovative technologies, or from unconventional ingredients, to which consumers might be unaccustomed.

Analysis from the University of Surrey suggests that the economies of countries such as America, the United Kingdom and Germany should prepare for a long slow recovery with prolonged periods of instability.

Rates of growth across member states of Organisation for Economic Co-operation and Development (OECD) have been in decline since the 1970s, a phenomenon known as 'secular stagnation'. The average growth in gross domestic product (GDP) per capita fell from over 4 percent in the mid-1960s to little more than 1 percent in the pre-pandemic years. The International Monetary Fund expects global GDP to decline by 5 percent this year alone (2020) with a contraction of 3 percent likely even in the emerging and developing market economies.1

In a paper published by Nature, researchers from Surrey's Centre for Understanding Sustainable Prosperity (CUSP) broke new research ground by applying critical slowing down (CSD) theory, typically used in physics and ecology, to analyse long-term trends in the global GDP datasets from as far back as the 1820s.2,3

CSD theory suggests that when a constrained, dynamic system is close to breaking point, its ability to recovery decreases. Fluctuations around the system's equilibrium become deeper and more pronounced because its internal stabilisation forces have weakened.

The team from CUSP found that, even before the Covid-19 crisis, many of the world's leading economies were experiencing larger slower growth cycles (recession cycles), suggesting precisely such a period of critical slowing down in the economic system. The team's analysis suggests that the added weight of the Covid-19 crisis may result in one of the weakest and most unstable recoveries in recorded history for many economies.

Professor Tim Jackson, Director of CUSP at the University of Surrey, said: "The global economy is facing one of the largest downturns since the Great Depression in the 1930s. Placing the economy on hold to prevent unfathomable human tragedy from the Covid-19 pandemic was the right decision. Trying to force our way back to economic growth now would be the wrong one. A post-growth world is the new normal.4

"It's time to rethink and remake the economic models that have been failing us for decades. The challenge is enormous. But so is the prize. CSD theory suggests that a resilient, sustainable economic system which protects the health of people and planet is now within our grasp."

SAN ANTONIO - The majority of children with COVID-19 in 26 countries fared well clinically compared to adults during the first four months of the pandemic, a newly released study shows.

Researchers from the Long School of Medicine at The University of Texas Health Science Center at San Antonio prepared the study, which is the largest systematic review to date of children and young adults with COVID-19. EClinicalMedicine, a journal of The Lancet, on June 26 published the results, which cover studies published between Jan. 24 and May 14.

Among the findings:

19% of the pediatric population with COVID-19 had no symptoms.

21% exhibited patchy lesions on lung X-rays.

5.6% suffered from co-infections, such as flu, on top of COVID-19.

3.3% were admitted to intensive care units.

Seven deaths were reported.

"Our data is compiled from 131 studies and encompasses 7,780 patients who span the pediatric age spectrum," said study senior author Alvaro Moreira, MD, MSc, assistant professor of pediatrics at UT Health San Antonio and a fellowship-trained neonatologist.

"In the study we report the most common symptoms, quantify laboratory findings and describe imaging characteristics of children with COVID-19," Dr. Moreira said. "Furthermore, we summarize treatments that were administered and offer an initial glimpse of a handful of patients who met the U.S. Centers for Disease Control and Prevention (CDC) criteria for multisystem inflammatory syndrome in children."

Symptoms

The most frequent symptoms, similar to the adult population, were fever and cough. Those were found in 59% and 56% of the pediatric population.

In 233 individuals, a past medical history was noted, and among this group, 152 were children with compromised immune systems or who had underlying respiratory or cardiac disease.

The number of children with excellent outcomes surprised the research team. "Although we are hearing about severe forms of the disease in children, this is occurring in very rare circumstances," Dr. Moreira said.

The majority of journal articles were from China. The largest study that was included was a case series of 2,572 patients reported by the U.S. CDC COVID-19 team.

Laboratory measures that were consistently abnormal in pediatric COVID-19 patients included inflammatory markers such as creatine kinase, interleukin-6 and procalcitonin.

Few severe cases

Thankfully, only a small number of patients met inclusion for multisystem inflammatory syndrome in children. Their disease paralleled the extreme forms of COVID-19 seen in adults.

"Children with systemic inflammation had a significant decrease in the amount of lymphocytes in their blood," Dr. Moreira said. "COVID-positive children who didn't have the extreme form of the disease had 42% lymphocytes in their blood, versus 11% in children with the multisystem syndrome."

Lymphocytes are one of the main types of immune cells in the body.

Kidney failure was seen in nine pediatric patients, liver failure also in nine and shock in 19. Mechanical ventilation was required by 42 patients.

The study does not take into consideration a new surge of patients in New York, England and Italy where specialists are now starting to see children with multisystem inflammatory syndrome, Dr. Moreira said.

Leipzig/Dresden. In connection with the effects of the COVID-19 pandemic, satellite measurements made headlines showing how much the air pollutant nitrogen dioxide (NO2) had decreased in China and northern Italy. In Germany, traffic density is the most important factor. However, weather also has an influence on NO2 concentrations, according to a study by the Leibniz Institute for Tropospheric Research (TROPOS), which evaluated the influence of weather conditions on nitrogen dioxide concentrations in Saxony 2015 to 2018 on behalf of the Saxon State Office for Environment, Agriculture and Geology (LfULG). It was shown that wind speed and the height of the lowest air layer are the most important factors that determine how much pollutants can accumulate locally.

In order to determine the influence of various weather factors on air quality, the team used a statistical method that allows meteorological fluctuations to be mathematically removed from long-term measurements. The air quality fluctuates, in some cases very strongly, due to different emissions and the influence of the weather. Until now, however, it has been difficult to estimate, what share legal measures such as low emission zones or diesel driving bans have and what share the weather influences have in the actual air quality? With the method used, this will be easier in the future.

Nitrogen dioxide (NO2) is an irritant gas which attacks the mucous membrane of the respiratory tract, causes inflammatory reactions as an oxidant and increases the effect of other air pollutants. As a precursor substance, it can also contribute to the formation of particulate matter. Limit values have been set in the EU to protect the population: For nitrogen dioxide, an annual average value of 40 micrograms per cubic metre of air applies (μg/m³). To protect the health of the population, measures must be taken if these limit values are not complied with. In 2018/2019, for example, various measures were taken in Germany, ranging from a reduction in the number of lanes (e.g. in Leipzig) to driving bans for older diesel vehicles (e.g. in Stuttgart).

To evaluate the effectiveness of such measures, it would be helpful to determine the exact influence of weather conditions. The Saxon State Office for Environment, Agriculture and Geology (LfULG) therefore commissioned TROPOS to carry out a study on the influence of weather factors on NO2 concentrations and provided its measurement data from the Saxon air quality measurement network and meteorological data for this purpose. The researchers were thus able to evaluate data from 29 stations in Saxony over a period of four years, which represent a cross-section of air pollution - from stations at traffic centres to urban and rural background stations and stations on the ridge of the Erzgebirge mountains. They also calculated the height of the lowest layer in the atmosphere and incorporated data from traffic counting stations in Leipzig and Dresden into the study. A method from the field of machine learning was used for the statistical modelling, the application of which in the field of air quality was first published by British researchers in 2009.

In this way, the study was able to demonstrate that the traffic density at all traffic stations is most significantly responsible for nitrogen oxide concentrations. However, two weather parameters also have a significant influence on nitrogen dioxide concentrations: wind speed and the height of the so-called mixing layer. The latter is a meteorological parameter that indicates the height to which the lowest layer of air, where the emissions mix, extends. "It was also shown that high humidity can also reduce the concentration of nitrogen dioxide, which could be due to the fact that the pollutants deposit more strongly on moist surfaces. However, the exact causes are still unclear," says Dominik van Pinxteren.

The statistical analysis has also enabled the researchers to remove the influence of the weather from the time series of pollutant concentrations: Adjusted for the weather, the concentration of nitrogen oxides (NOx) decreased by a total of 10 micrograms per cubic meter between 2015 and 2018 on average over all traffic stations in Saxony. In urban and rural areas and on the ridge of the Erzgebirge, however, NOx concentrations tend to remain at the same level. Even though there have been some improvements in air quality in recent years, there are good scientific arguments for further reducing air pollution.

In a way, this also applies to premature conclusions from the corona crisis: in order to find out how strong the influence of the initial restrictions on air quality actually was, the influence of the weather would have to be statistically removed in a longer series of measurements. To this end, investigations for the Leipzig area are currently underway at TROPOS, as is a Europe-wide study of the EU research infrastructure for short-lived atmospheric constituents such as aerosol, clouds and trace gases (ACTRIS), the German contribution to which is coordinated by TROPOS. Tilo Arnhold

The nature of the sediments on the Basque continental shelf is very heterogeneous. From the point of view of distribution, two clearly differentiated sectors can be picked out in terms of grain size. "In the area of Bizkaia medium to coarse-sized sands predominate, whereas on the coast of Gipuzkoa there is a predomination of deposits of very fine sand, silts and clays, currently known as the Basque Mud Patch (BMP)," explained Maria Jesus Irabien, researcher in the UPV/EHU's Department of Mineralogy and Petrology.

"This mud patch has an irregular surface area of approximately 680 km2. Metals and contaminants, in general, are more likely to build up in this type of muddy material. So if what we are aiming to do is study anthropogenic, industrial or human influence, it is necessary to explore the mud patch in the area of Gipuzkoa," said the researcher in the Harea: Coastal Geology group of the UPV/EHU.

So, as Irabien pointed out, "we analysed three cores (19-46 cm deep) from a multidisciplinary perspective that includes the analysis of various metals, foraminifera (small organisms characterised by a shell or chalky conch), pollen and various natural and artificial isotopes".

"The results obtained have made it possible to calculate that the sediments build up at an approximate rate of one millimetre per year. An increase in the concentrations of metals from the end of the 19th century onwards can also be observed, showing that the influence of industrialization and human activity taking place in the Basque Country extends to the marine environment. In the case of lead (Pb), for example, the content in the most recent samples is five times higher than in that recorded in the past. However, the foraminifera are not affected by this contamination. Finally, the pollen analysis displays a growing trend in conifers and a reduction in indigenous species (Deciduous Quercus), possibly as a result of reforestation," highlighted the researcher of the Harea: Coastal Geology group of the UPV/EHU.

"The results confirm that the influence of coastal anthropogenic activities extends to the adjacent shelf where muddy deposits are likely to act as a trap for contaminants," said Irabien.

The researcher stresses "the importance of continuing to make interpretations of this type in marine depths to get to know marine evolution from a historical perspective. It is clear that human activity is exerting a significant influence on the coast, too; the only advantage that all this has is knowing we can stop," concluded María Jesús Irabien.

New Orleans, LA - A paper published by Paul Fidel, Jr., PhD, Professor and Director of the Center of Excellence in Oral and Craniofacial Biology and Associate Dean for Research at LSU Health New Orleans School of Dentistry, and Mairi Noverr, PhD, Professor of Microbiology & Immunology at Tulane University School of Medicine in New Orleans, suggests that live attenuated vaccines such as MMR (measles, mumps and rubella) may prevent the severe lung inflammation and sepsis associated with COVID-19 infection. The paper was published online in mBio
Increasing evidence demonstrates that live attenuated vaccines can activate nonspecific immune cells to train leukocytes (the white blood cells of the immune system) to mount a more effective defense against unrelated infections. The researchers demonstrated in a laboratory that vaccination with a live attenuated fungal strain generated trained innate protection against lethal sepsis (blood poisoning) caused by a combination of disease-causing fungi and bacteria.

The authors propose that the protection from an unrelated live attenuated vaccine is produced by long-lived myeloid-derived suppressor cells (MDSCs) previously reported to inhibit septic inflammation and mortality in several experimental models. They stress that this live attenuated MMR vaccine concept is NOT in any way suggested to be directed against COVID-19, but instead an immune preventive measure against the severe inflammatory symptoms of COVID-19.

"The use of childhood live attenuated vaccines such as MMR given to adults to induce bystander cells that can dampen or reduce severe complications associated with COVID-19 infection is a low risk - high reward preventive measure during a critical period of the pandemic," notes Dr. Fidel. "These bystander cells are long-lived but not life-long. Anyone who had an MMR vaccination as a child, while likely to still have immune antibodies directed against measles, mumps, or rubella, will not likely still have the immune cells directed against sepsis. So, it could be important to get the MMR vaccination as an adult to protect better against COVID-related sepsis."

A similar concept is being tested in other countries. The authors write "at least six clinical trials have been initiated in Europe, Australia, and the United States to test vaccination with Mycobacterium bovis BCG (live attenuated tuberculosis [TB] vaccine) or placebo in high-risk health care workers to determine whether beneficial trained innate responses against COVID-19 can be elicited."

In contrast, Fidel and Noverr propose that the trained innate response includes induction of the MDSCs that can inhibit/reduce the severe lung inflammation/sepsis associated with COVID-19.

"While we initiate the clinical trials and animal model studies to test the hypothesis that the MMR vaccine given to adults induces the bystander cells that we propose can inhibit the severe lung inflammation/sepsis associated with COVID-19 infection, we suggest adults working in high-risk settings who are not immunocompromised, pregnant or allergic to vaccinations, get an MMR vaccine/booster," Fidel concludes. "If we're correct, an MMR-vaccinated person may suffer less if infected with COVID-19. If we're wrong, the person has better immunity to measles, mumps, and rubella. A sort of no harm no foul action."

In a new study of axion motion, researchers propose a scenario known as "kinetic misalignment" that greatly strengthens the case for axion/dark matter equivalence. The novel concept answers key questions related to the origins of dark matter and provides new avenues for ongoing detection efforts. This work, published in Physical Review Letters, was conducted by researchers at the Institute for Advanced Study, University of Michigan, and UC Berkeley.

The existence of dark matter has been confirmed by several independent observations, but its true identity remains a mystery. According to this study, axion velocity provides a key insight into the dark matter puzzle. Previous research efforts have successfully accounted for the abundance of dark matter in the universe; however certain factors, such as the underproduction of axions with stronger ordinary matter interactions, remained unexplored.

By assigning a nonzero initial velocity to the axion field, the team discovered a mechanism--termed kinetic misalignment--producing far more axions in the early universe than conventional mechanisms. The motion, generated by breaking of the axion shift symmetry, significantly modifies the conventional computation of the axion dark matter abundance. Additionally, these dynamics allow axion dark matter to react more strongly with ordinary matter, exceeding the prediction of the conventional misalignment mechanism.

"The extensive literature on the axion was built upon the assumption that the axion field is initially static in the early universe," stated Keisuke Harigaya of the Institute for Advanced Study. "Instead, we discovered that the axion field may be initially dynamic as a consequence of theories of quantum gravity with axions."

Two members of the research team, Keisuke Harigaya and Raymond Co, previously explored the concept of axion dynamics in the study "Axiogenesis," which explained how the excess of matter over antimatter could be due to a nonzero initial velocity of the QCD axion field. This study also provided a framework for generating new insights into the questions surrounding dark matter.

"This new kinetic misalignment mechanism predicts an axion with a larger interaction strength and may be discovered in planned experimental searches," stated Raymond Co of the University of Michigan. "Our discovery of new axion dynamics thus opens up unexplored research avenues for theoretical and experimental particle physics and cosmology."

To date, the axion has proven incredibly versatile. The particle was originally proposed to solve the mystery of why neutrons do not interact with an electric field despite having charged constituents. Former IAS Professor Frank Wilczek, who coined the term axion, published his landmark findings in 1978 in Physical Review Letters while a Member of the Institute for Advanced Study's School of Natural Sciences.