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It is assumed that the brain has homeostatic mechanisms to prevent the depletion of cellular energy, required for all cellular activities. For example, the blood flow increases, and oxygen and glucose are actively delivered in the brain region in which neural firing activity occurs. Besides, the cerebral blood flow and glucose uptake into the cells fluctuate accompanying the variations of cellular activities in the brain across the sleep-wake states of animals. Under these brain energy homeostatic mechanisms, it is assumed that the cellular energy status in the brain could be maintained constant in all physiological conditions including across the sleep-wake states of animals. However, this has not been experimentally proven.

To investigate whether the cellular energy status in the brain of living animals is always constant or variated, the researchers measured the neuronal intracellular concentration of adenosine 5'-triphosphate (ATP), the major cellular energy metabolite, using a fluorescent sensor in the brain of living mice. Using an optical fiber and wide-field microscopy, they showed a cortex-wide variation of cytosolic ATP levels in the cortical neurons depending on the sleep-wake states of animals: The ATP levels were high during the waking state, decreased during non-REM sleep, and profoundly decreased during REM sleep. On the other hand, cerebral blood flow, as a metabolic parameter for energy supply, slightly increased during non-REM sleep and greatly increased during REM sleep, compared with the waking state. The reduction in neuronal ATP levels was also observed under general anesthesia in mice and response to local brain electrical stimulation for neuronal activation, whereas the hemodynamics was simultaneously enhanced.

Since the neuronal ATP levels increase throughout the cortex in the waking state, which is when the cellular energy demand increases, brain mechanisms for energy modulation could increase the neuronal ATP levels in a cortex-wide manner in response to the sleep-to-wake transition of animals. Meanwhile, the great reduction of neuronal ATP levels during REM sleep despite a simultaneous increase of cerebral hemodynamics for energy supply suggests negative energy balance in neurons, which could be due to REM sleep-specific promotion of energy-consuming activities such as heat production. The significant reduction of ATP levels in the cortical neurons during REM sleep is expected to use as a novel biomarker of REM sleep. Eventually, cerebral energy metabolism may not always meet neuronal energy demands, consequently resulting in physiological fluctuations of intracellular ATP levels in neurons.

Adaptive radiation - the rapid evolution of many new species from a single ancestor - is a major focus in evolutionary biology. Adaptive radiations often show remarkable repeatability where lineages have undergone multiple episodes of adaptive radiation in distant places and at various points in time - implying their extraordinary evolutionary potential.

Now, researchers from the Swiss Federal Institute of Aquatic Science and Technology and Tohoku University have developed a novel "individual-based model" that simulates the evolution of an ecosystem of virtual organisms. This model reveals additional information about recurrent adaptive radiation and the role that hybridization plays in that process.

Hybridization - the interbreeding of different species - generates extraordinary genetic variation by mixing and recombining genetic materials from different species. Then the enriched genetic variation can facilitate rapid adaptive radiation into various unoccupied habitats if available. However, hybridization generates large genetic variation locally and for a short period, meaning the simultaneous coexistence of hybridization and unoccupied habits is rare. Because of this, hybridization seemed unlikely to explain the recurrent adaptive radiation in the same lineage.

Yet, a recent genomics study on adaptive radiations of East African cichlid fish caused researchers to reevaluate what they previously thought. The study discovered that a genetic variation generated through an ancient hybridization event permanently increased evolutionary potential of the descendant lineage and facilitated a recurrent adaptive radiation of the lineage in several geographically distant lakes - one of which started over 100000 years after the hybridization event.

To address this theoretical conundrum, Kotaro Kagawa and his colleague Ole Seehausen used their individual-based model to simulate the evolutionary dynamics caused by hybridization under various geographic, ecological, and historical scenarios. Results from over 15000 simulations provided two theoretical findings. First, simulations showed that hybridization-derived genetic variation geographically spreads and persists for long periods only if the hybrid population becomes separated into isolated sub-lineages. Subsequent secondary hybridization of the sub-lineages can potentially reestablish genetic polymorphisms from the ancestral hybridization in places far from the birthplace of the hybrid-clade and long after the ancestral hybridization event. This leads to the second finding: genetic variation generated through a single hybridization event could lead to multiple independent episodes of adaptive radiation far apart in location and time when ecological and geographic conditions promote the temporal isolation and subsequent admixture of sub-lineages.

"These findings provide not only an explanation for the recurrent adaptive radiation of African cichlids but also a novel insight that exceptional genetic variation, once generated through a rare hybridization event, may significantly influence clade-wide macroevolutionary trends ranging over large spatial and temporal scales," said Dr. Kagawa.

Humans are exposed continuously to the menace of viral diseases such as those caused by the Ebola virus, Zika virus and coronaviruses. Such emerging/re-emerging viral outbreaks can be triggered by cross-species viral transmission from wild animals to humans.

To achieve cross-species transmission, new hosts have to be exposed to the virus from the old host. Next, the viruses acquire certain mutations that can be beneficial for replicating in the new hosts. Finally, through sustained transmission in the new host, the viruses adapt further evolving as a new virus in the new host (Figure 1). However, at the outset of this process, the viruses have to overcome "the species barriers", which hamper viral cross-species transmission. Mammals including humans have "intrinsic immunity" mechanisms that have diverged enough in evolution to erect species barriers to viral transmission.

HIV-1 most likely originated from related precursors found in chimpanzees and gorillas

HIV-1, the causative agent of AIDS, most likely originated from related precursors found in chimpanzees (SIVcpz) and gorillas (SIVgor), approximately 100 years ago (Figure 2).

Additionally, SIVgor most likely emerged through the cross-species jump of SIVcpz from chimpanzees to gorillas (Figure 2).

However, it remains unclear how primate lentiviruses successfully transmitted among different species. To limit cross-species lentiviral transmission, cellular "intrinsic immunity", including APOBEC3 proteins potentially inhibit lentiviral replication. In contrast, primate lentiviruses in this evolutionary "arms race" have acquired their own "weapon", viral infectivity factor (Vif), to antagonize the antiviral effect of restriction factors.

Suggesting that a great ape APOBEC3 protein can potentially restrict the cross-species transmission of great ape lentiviruses

A research group at The Institute of Medical Science, The University of Tokyo (IMSUT) showed that gorilla APOBEC3G potentially plays a role in inhibiting SIVcpz replication. Intriguingly, the research group demonstrated that an amino acid substitution in SIVcpz Vif, M16E, is sufficient to overcome gorilla APOBEC3G-mediated restriction.

"To our knowledge, this is the first report suggesting that a great ape APOBEC3 protein can potentially restrict the cross-species transmission of great ape lentiviruses and how lentiviruses overcame this species barrier. Moreover, this is the first investigation elucidating the molecular mechanism by which great ape lentiviruses achieve cross-species transmission", said the lead scientist, Kei Sato, Associate Professor (Principal Investigator) in the Division of Systems Virology, Department of Infectious Disease Control, IMSUT.

New international research into the Moon provides scientists with insights as to how and why its crust is magnetised, essentially 'debunking' one of the previous longstanding theories.

Australian researcher and study co-author Dr Katarina Miljkovic, from the Curtin Space Science and Technology Centre, located within the School of Earth and Planetary Sciences at Curtin University, explained how the new research, published by Science Advances, expands on decades of work by other scientists.

"There are two long term hypotheses associated with why the Moon's crust might be magnetic: One is that the magnetisation is the result of an ancient dynamo in the lunar core, and the other is that it's the result of an amplification of the interplanetary magnetic field, created by meteoroid impacts," Dr Miljkovic said.

"Our research is a deep numerical study that challenges that second theory - the impact-related magnetisation - and it essentially 'debunks' it. We found that meteoroid impact plasmas interact much more weakly with the Moon compared to the magnetisation levels obtained from the lunar crust.

"This finding leads us to conclude that a core dynamo is the only plausible source of the magnetisation of the Moon's crust."

To carry out her portion of the research, Dr Miljkovic provided the team with numerical estimates of the vapour formation that occurred during large meteoroid impact bombardment on the Moon approximately 4 billion years ago.

"When we look at the Moon with the naked eye, we can see these large craters caused by ancient meteoroid impacts. They are now filled with volcanic maria, or seas, causing them to look darker on the surface," Dr Miljkovic said.

"During these impact events, the meteoroids hit the Moon at a very high speed, causing displacement, melting, and vaporisation of the lunar crust.

"My work calculated the mass and thermal energy of the vapour emitted during these impacts. That was then used as input for further calculations and investigation of the behaviour of the ambient magnetic field at the Moon, following these large impact events.

"Basically, we made a much more inclusive, high fidelity and high-resolution investigation that led to debunking of the older hypothesis."

The study's lead researcher Dr Rona Oran, a research scientist in the Department of Earth, Atmospheric and Planetary Sciences (EAPS) at the Massachusetts Institute of Technology (MIT), said the impact simulations, combined with plasma simulations, harness the latest developments in scientific codes and computing power and allowed the team to perform the first simulations that could realistically capture and test this long-proposed mechanism.

Using such tools was key to allowing the team to look at many different scenarios, and in this way to rule out this mechanism under any feasible conditions that could have existed during the impact. This refutation could have important implications to determine what did magnetise the Moon, and even other objects in the solar system with unexplainable magnetised crusts.

"In addition to the Moon, Mercury, some meteorites, and other small planetary bodies all have a magnetic crust. Perhaps other equivalent mechanical dynamo mechanisms, such as those we now believe to have been in operation on the Moon, could have been in effect on these objects as well," Dr Oran said.

Millions of people plant pollinator gardens in an effort to provide monarch butterflies with food along their annual migration route from overwintering sites in the highland forests of central Mexico to summer breeding grounds in the United States and southern Canada. For the first time, entomologists studied how effective native milkweed cultivars in small gardens are at attracting and supporting monarchs - their results suggest that this can be a valuable additional food source.

Plant cultivars are natural variants of native plants that have been deliberately collected, selected, cross-bred or hybridized for desirable traits that can be maintained through propagation. Although experts generally discourage using cultivars for ecological restoration in natural habitats such as forests and wetlands, consumers find them attractive when seeking new plants that combine the attributes of natives and ornamentals. For the nursery industry, cultivars open the door to new introductions and vast market potential. Indeed, most native plants sold at most garden centers are available only as cultivars as opposed to true or ''wild type'' native species.

Researchers Adam Baker and Daniel Potter from the University of Kentucky College of Agriculture, Food and Environment set out to study whether or not native milkweed cultivars, planted by 'citizen ecologists', were effective in helping to support the declining monarch butterfly populations.

"Native milkweed cultivars including those selected for novel floral display, longer blooming duration, compact growth form and other consumer-attractive traits are increasingly available in wholesale nurseries and at local garden centers," said Baker. "It is important to determine whether these cultivars have the same ability as wild-type native plants to attract monarchs and bees and contribute to effective ecological gardens."

In the study, Baker, Potter and their collaborators planted six urban gardens each containing two species of native wild-type milkweeds (swamp and butterfly), along with three cultivars of each species. They monitored them for monarch and bee visitation for two summers. In both years, monarchs laid many more eggs on swamp milkweed than on butterfly milkweed, despite both species being equally suitable food for the caterpillars. Importantly, in both milkweed species, they found the native cultivars were just as attractive and suitable for monarchs as the respective wild-type counterparts from which those cultivars were derived.

"Previous research has shown that monarch butterflies tend to lay more eggs on taller milkweeds than on shorter ones," Potter said. "We think that is what has happened in our study because swamp milkweed is significantly taller than butterfly milkweed, and probably easier for the egg-laying female monarchs to find."

Milkweeds produce a lot of nectar, so besides monarchs they also attract and help to sustain native bees, honeybees, various butterflies and many other nectar-feeding insects. In the study, the scientists identified more than 2,400 bees, representing five bee families and 17 genera, visiting the milkweeds while they were in bloom. They found that swamp milkweed and its cultivars attracted proportionately more large bees, including bumble bees, carpenter bees, and honeybees, whereas butterfly milkweeds attract proportionately more small native bees. Importantly, within each native milkweed species, the cultivars attracted similar bees as their native counterparts.

These findings suggest that the efforts of individual gardeners to plant milkweed, either wild-type native plants or native cultivars, can be helpful in supporting the declining populations of both monarch butterflies and other insects.

Epilepsy is one of the most common neurological diseases. It is caused by a malfunction in brain cells and is usually treated with medicines that control or counteract the seizures.

Scientists from the Faculty of Health and Medical Sciences, University of Copenhagen and Rigshospitalet have now identified the exact neurons that are most affected by epilepsy. Some of which have never been linked to epilepsy before. The newfound neurons might contribute to epileptogenesis - the process by which a normal brain develops epilepsy - and could therefore be ideal treatment targets.

'Our findings potentially allows for the development of entirely new therapeutic approaches tailored towards specific neurons, which are malfunctioning in cases of epilepsy. This could be a breakthrough in personalized medicine-based treatment of patients suffering from epileptic seizures,' says Associate Professor Konstantin Khodosevich from Biotech Research & Innovation Center (BRIC), Faculty of Health and Medical Sciences.

A major step towards more effective drugs

It is the first time a study investigates how every single neuron in the epileptic zone of the human brain is affected by epilepsy. The researchers have analyzed more than 117,000 neurons, which makes it the largest single cell dataset for a brain disorder published so far.

Neurons have been isolated from tissue resected from patients being operated as part of the Danish Epilepsy Surgery Programme at Rigshospitalet in Copenhagen.

'These patients continue to have seizures despite the best possible combination of anti-seizure drugs. Unfortunately, this is the case for 30-40 % of epilepsy patients. Active epilepsy imposes serious physical, cognitive, psychiatric and social consequences on patients and families. A more precise understanding of the cellular mechanism behind epilepsy could be a major step forward for developing drugs specifically directed against the epileptogenic process compared to the current mode of action reducing neuronal excitability in general throughout the brain' says associate professor Lars Pinborg, head of the Danish Epilepsy Surgery Program at Rigshospitalet.

From 'neuronal soup' to single cell analysis

The study from the Khodosevich Group differs from previous work by using single cell analysis. Earlier studies on neuronal behavior in regards to epilepsy have taken a piece of the human brain and investigated all the neurons together as a group or a 'neuronal soup'. When using this approach, diseased cells and healthy cells are mixed together, which makes it impossible to identify potential treatment targets.

'By splitting the neurons into many thousands of single cells, we can analyze each of them separately. From this huge number of single cells, we can pinpoint exactly what neurons are affected by epilepsy. We can even make a scale from least to most affected, which means that we can identify the molecules with the most promising potential to be effective therapeutic targets', says Konstantin Khodosevich.

Next step is to study the identified neurons and how their functional changes contribute to epileptic seizures. The hope is to then find molecules that can restore epilepsy related neuronal function back to normal and inhibit seizure generation.

Expanding knowledge on underlying mechanisms of epilepsy

The study confirms expression from key genes known from a number of previous studies, but is also a dramatic expansion of knowledge on the subject. Previously, gene expression studies have identified a couple of hundred genes that changes in epilepsy.

'We show that the complexity of gene expression in epilepsy is much larger than previously known. It is not a matter of a handful or a few hundred genes changing. Our study proves that thousands of genes in different neurons change their expression in epilepsy. From these thousands of gene expression changes, we identified those that most likely contribute to epileptogenesis. Now it is time to prove it functionally,' says Konstantin Khodosevich.

A mathematician from Cardiff University has developed a new method for processing large volumes of COVID-19 tests which he believes could lead to significantly more tests being performed at once and results being returned much quicker.

Dr Usama Kadri, from the University's School of Mathematics, believes the new technique could allow many more patients to be tested using the same amount of tests tubes and with a lower possibility of false negatives occurring.

Dr Kadri's technique, which has been published in the journal Health Systems, uses simple algebraic equations to identify positive samples in tests and takes advantage of a testing technique known as 'pooling'.

Pooling involves grouping a large number of samples from different patients into one test tube and performing a single test on that tube.

If the tube is returned negative then you know that everybody from that group does not have the virus.

Pooling can be applied by laboratories to test more samples in a shorter space of time, and works well when the overall infection rate in a certain population is expected to be low.
If a tube is returned positive then each person within that group needs to be tested once again, this time individually, to determine who has the virus.

In this instance, and particularly when it is known that infection rates in the population are high, the savings from the pooling technique in terms of time and cost become less significant.

However, Dr Kadri's new technique removes the need to perform a second round of tests once a batch is returned positive and can identify the individuals who have the virus using simple equations.

The technique works with a fixed number of individuals and test tubes, for example 200 individuals and 10 test tubes, and starts by taking a fixed number of samples from a single individual, for example 5, and distributing these into 5 of the 10 test tubes.

Another 5 samples are taken from the second individual and these are distributed into a different combination of 5 of the 10 tubes.

This is then repeated for each of the 200 individuals in the group so that no individual shares the same combination of tubes.

Each of the 10 test tubes is then sent for testing and any tube that returns negative indicates that all patients that have samples in that tube must be negative.

If only one individual has the virus, then the combinations of the tubes that return positive, which is unique to the individual, will directly indicate that individual.

However, if the number of positive tubes is larger than the number of samples from each individual, in this example 5, then there should be at least two individuals with the virus.

The individuals that have all of their test tubes return positive are then selected.

The method assumes that each individual that is positive should have the same quantity of virus in each tube, and that each of the individuals testing positive will have a unique quantity of virus in their sample which is different to the others.

From this, the method then assumes that there are exactly two individuals with the virus and, for every two suspected individuals, a computer is used to calculate any combination of virus quantity that would return the actual overall quantity of virus that was measured in the tests.

If the right combination is found then the selected two individuals have to be positive and no one else. Otherwise, the procedure is repeated but with an additional suspected individual, and so on until the right combination is found.

"Applying the proposed method allows testing many more patients using the same number of testing tubes, where all positives are identified with no false negatives, and no need for a second round of independent testing, with the effective testing time reduced drastically," Dr Kadri said.

So far, the method has been assessed using simulations of testing scenarios and Dr Kadri acknowledges that lab testing will need to be carried out to increase confidence in the proposed method.

Moreover, for clinical use, additional factors need to be considered including sample types, viral load, prevalence, and inhibitor substances.

Diamonds have a firm foothold in our lexicon. Their many properties often serve as superlatives for quality, clarity and hardiness. Aside from the popularity of this rare material in ornamental and decorative use, these precious stones are also highly valued in industry where they are used to cut and polish other hard materials and build radiation detectors.

More than a decade ago, a new property was uncovered in diamonds when high concentrations of boron are introduced to it - superconductivity. Superconductivity occurs when two electrons with opposite spin form a pair (called a Cooper pair), resulting in the electrical resistance of the material being zero. This means a large supercurrent can flow in the material, bringing with it the potential for advanced technological applications. Yet, little work has been done since to investigate and characterise the nature of a diamond's superconductivity and therefore its potential applications.

New research led by Professor Somnath Bhattacharyya in the Nano-Scale Transport Physics Laboratory (NSTPL) in the School of Physics at the University of the Witwatersrand in Johannesburg, South Africa, details the phenomenon of what is called "triplet superconductivity" in diamond. Triplet superconductivity occurs when electrons move in a composite spin state rather than as a single pair. This is an extremely rare, yet efficient form of superconductivity that until now has only been known to occur in one or two other materials, and only theoretically in diamonds.

"In a conventional superconducting material such as aluminium, superconductivity is destroyed by magnetic fields and magnetic impurities, however triplet superconductivity in a diamond can exist even when combined with magnetic materials. This leads to more efficient and multifunctional operation of the material," explains Bhattacharyya.

The team's work has recently been published in an article in the New Journal of Physics, titled "Effects of Rashba-spin-orbit coupling on superconducting boron-doped nanocrystalline diamond films: evidence of interfacial triplet superconductivity". This research was done in collaboration with Oxford University (UK) and Diamond Light Source (UK). Through these collaborations, beautiful atomic arrangement of diamond crystals and interfaces that have never been seen before could be visualised, supporting the first claims of 'triplet' superconductivity.

Practical proof of triplet superconductivity in diamonds came with much excitement for Bhattacharyya and his team. "We were even working on Christmas day, we were so excited," says Davie Mtsuko. "This is something that has never been before been claimed in diamond," adds Christopher Coleman. Both Mtsuko and Coleman are co-authors of the paper.

Despite diamonds' reputation as a highly rare and expensive resource, they can be manufactured in a laboratory using a specialised piece of equipment called a vapour deposition chamber. The Wits NSTPL has developed their own plasma deposition chamber which allows them to grow diamonds of a higher than normal quality - making them ideal for this kind of advanced research.

This finding expands the potential uses of diamond, which is already well-regarded as a quantum material. "All conventional technology is based on semiconductors associated with electron charge. Thus far, we have a decent understanding of how they interact, and how to control them. But when we have control over quantum states such as superconductivity and entanglement, there is a lot more physics to the charge and spin of electrons, and this also comes with new properties," says Bhattacharyya. "With the new surge of superconducting materials such as diamond, traditional silicon technology can be replaced by cost effective and low power consumption solutions".

The induction of triplet superconductivity in diamond is important for more than just its potential applications. It speaks to our fundamental understanding of physics. "Thus far, triplet superconductivity exists mostly in theory, and our study gives us an opportunity to test these models in a practical way," says Bhattacharyya.

Ultraviolet light from giant stellar flares can destroy a planet's habitability. New research from the University of North Carolina at Chapel Hill will help astrobiologists understand how much radiation planets experience during super flares and whether life could exist on worlds beyond our solar system.

Super flares are bursts of energy that are 10 to 1,000 times larger than the biggest flares from the Earth's sun. These flares can bathe a planet in an amount of ultraviolet light huge enough to doom the chances of life surviving there.

Researchers from UNC-Chapel Hill have for the first time measured the temperature of a large sample of super flares from stars, and the flares' likely ultraviolet emissions. Their findings, published Oct. 5 ahead of print in Astrophysical Journal, will allow researchers to put limits on the habitability of planets that are targets of upcoming planet-finding missions.

"We found planets orbiting young stars may experience life-prohibiting levels of UV radiation, although some micro-organisms might survive," said lead study author Ward S. Howard, a doctoral student in the Department of Physics and Astronomy at UNC-Chapel Hill.

Howard and colleagues at UNC-Chapel Hill used the UNC-Chapel Hill Evryscope telescope array and NASA's Transiting Exoplanet Survey Satellite (TESS) to simultaneously observe the largest sample of super flares.

The team's research expands upon previous work that has largely focused on flare temperatures and radiation from only a handful of super flares from a few stars. In expanding the research, the team discovered a statistical relationship between the size of a super flare and its temperature. The temperature predicts the amount of radiation that potentially precludes on-surface life.

Super flares typically emit most of their UV radiation during a rapid peak lasting only five to 15 minutes. The simultaneous Evryscope and TESS observations were obtained at two-minute intervals, ensuring multiple measurements were taken during the peak of each super flare.

This is the first time the temperatures of such a large sample of super flares has ever been studied. The frequency of observations allowed the team to discover the amount of time super flares can cook orbiting planets with intense UV radiation.

The flares observed have already informed the TESS Extended Mission to discover thousands of exoplanets in orbit around the brightest dwarf stars in the sky. TESS is now targeting high priority flare stars from the UNC-Chapel Hill sample for more frequent observations.

"Longer term these results may inform the choice of planetary systems to be observed by NASA's James Webb Space Telescope based on the system's flaring activity," said study co-author Nicholas M. Law, associate professor of physics and astronomy at UNC-Chapel Hill and principal investigator of the Evryscope telescope.

"We found that - over the longer term - the links between plant traits and ecosystem functions were indeed very weak, as we could only explain about 12 per cent of the variance in ecosystem functioning," said the paper's lead author, Dr Fons van der Plas from the Institute of Biology at Leipzig University. Together with colleagues from the German Centre for Integrative Biodiversity Research (iDiv) and other research institutions in Germany and abroad, he found different patterns than in previous studies - which had focused on short-term links between plant traits and ecosystem functions. These had previously assumed much stronger links between plant traits and ecosystem functioning.

"The main difference between our studies and earlier ones was that we carried out our work over a period of ten years, while most other studies were based on data measured in just one year," said the biologist. The relationships between plant traits and ecosystem functions changed from year to year: some species become locally extinct, while others replace them.

Scientists often ask themselves how this change in biodiversity affects the way ecosystems function, for example in terms of biomass production, carbon sequestration and pollination. In predicting these consequences, they rely on the traits in which plants differ. For example, some plant species are pollinated by insects, and others by the wind. They hope that knowing which species will be more common in the future and what traits these species have will enable them to make more precise predictions.

The research team led by van der Plas has now discovered, for example, that plant biomass production was maximised in plant communities dominated by species with thick roots in some years and by completely different plant communities in others. In almost every year, a different plant trait was found to have been important for maximising biomass production. According to van der Plas, it is therefore extremely difficult to predict exactly how changes in plant communities affect the functioning of ecosystems over long periods of time.

Ganoderma lucidum, known as Yeongji mushroom in Korea, is called a modern-day elixir plant and has long been used medicinally in China, Japan and Korea. Ganoderic acid, an active ingredient found in the mushroom, is known for its excellence in enhancing the immune function of cells. Due to the hard texture of the mushroom, it has been ingested in powder or liquid form, but it has been noted that the active ingredient becomes destroyed when the mushroom is dried for an extended period of time or the extraction is performed at high heat (80 °C or higher).

The Korea Institute of Science and Technology (KIST) announced that a team led Dr. Ho-Youn Kim of the Smart Farm Research Center of the Gangneung Natural Products Informatics Center determined the conditions for enhancing the anti-inflammatory, anti-diabetic, and antioxidant effects of Ganoderma lucidum and confirmed its marketability as an anti-inflammatory agent for the skin.

In order to reduce the amount of the active ingredient destroyed and increase the efficacy, the KIST research team extracted the active ingredient after drying the mushroom at various temperatures and times, through which they pinpointed the optimal conditions to achieve the best possible anti-inflammatory, antioxidant and anti-diabetic effects. As a result, it was confirmed that drying with hot air at 60°C led to excellent anti-inflammatory properties, as it led to the extraction of a large amount of ganoderic acid, while outstanding antioxidant and antidiabetic activities resulted from freeze-drying the mushroom at -50°C.

Also, an experiment was carried out using the extract from hot air-dried Ganoderma lucidum on inflammation-induced keratinocytes, and the results showed that it effectively suppressed skin inflammation. The extraction conditions yielding such an effective active ingredient for skin inflammation have never been revealed before, and thus a patent application has been filed (Patent No.: 10-2020-0041577).

It is believed that the results of this study regarding the effect of varying the drying and extraction conditions on the antioxidant, antidiabetic, and anti-inflammatory activities of Ganoderma lucidum will be useful in developing processed products with the mushroom in the future.

Dr. Kim from KIST who spearheaded the research said, "Since the efficacy of Yeongji mushrooms (Ganoderma lucidum) varies depending on the drying and extraction methods, the drying method should be selected according to the purpose of use. It is expected that the findings of this study will not only raise the utility of the mushroom but also lead to the development of therapeutic agents for inflammatory skin conditions such as psoriasis and atopic dermatitis in the future."

Trust in public institutions is linked to fewer COVID-19 deaths, but trust and belonging to groups is associated with more deaths, according to a wide-ranging, McGill-led study of 30-day COVID-19 mortality rates in 84 countries. Greater economic inequality is also associated with COVID-19 mortality.

The study led by McGill researchers published in Social Science & Medicine, is the first to show how global differences in COVID-19 mortality relate to income inequality. It also includes surveys on social trust and confidence in public institutions representing 86% of the global population.

The trouble with trust

The analysis reveals that COVID-19 mortality is linked to differences in trust. A lack of confidence in state institutions was associated with more deaths - consistent with research during the SARS and H1N1 pandemics. Surprisingly, however, the researchers found that social trust and belonging is also associated with mortality. While connecting with friends and family is a natural response in times of crisis, in some countries, this trust and the desire to socialize may be interfering with efforts to contain transmission through physical distancing.

Moreover, strong group bonds can sometimes reinforce risky health behaviours, so that high-trusting societies may be more susceptible to misinformation about the severity of COVID-19, bogus treatments, or dismissive attitudes towards physical distancing. "People expect there are health benefits to trusting others and belonging to groups - and there usually are. But in the context of a pandemic, when you need people to self-isolate, blind trust in others can get in the way," says lead author Frank Elgar, a professor at McGill University and Canada Research Chair in Social Inequality in Child Health.

On the other hand, confidence in public institutions and civic participation were linked to fewer deaths, possibly because they mobilise people to wear masks, wash their hands, and practice physical distancing. The researchers note that being engaged in the community is particularly beneficial when groups are asked to compromise some personal freedom for the common good, like wearing a mask in public.

"Governments and other organisations can capitalise on this engagement during a pandemic by supporting safe ways for people to socialise and remain involved in their communities and cultural activities."

Inequality, not just poverty, a health problem during the pandemic

The researchers also found that income inequality is associated with more deaths, even after accounting for other social factors like national wealth and population age. "Countries with a larger gap between rich and poor, like the United States, Russia, and Brazil are experiencing a more deadly pandemic," says Elgar, who is also a member of the Department of Psychiatry in the Faculty of Medicine.

"In many countries, lower-wage workers are over-represented among the essential workers in retail, public transit, and health care settings who cannot easily practice physical distancing," says Elgar. Greater exposure to the virus and less access to health services among the poor could explain why more economically unequal countries - not necessarily the poorest countries - experienced significantly higher mortality rates. The researchers note, however, that wealthier countries may also have more accurate data or shorter lags in supplying death counts to health officials.

"There is a serious message here about the new challenges we will likely face in this second wave of the pandemic, and our capacity to mount a defense," says Elgar.

New Haven, Conn. -- A growing body of research suggests the planet Venus may have had an Earth-like environment billions of years ago, with water and a thin atmosphere.

Yet testing such theories is difficult without geological samples to examine. The solution, according to Yale astronomers Samuel Cabot and Gregory Laughlin, may be closer than anyone realized.

Cabot and Laughlin say pieces of Venus -- perhaps billions of them -- are likely to have crashed on the moon. A new study explaining the theory has been accepted by the Planetary Science Journal.

The researchers said asteroids and comets slamming into Venus may have dislodged as many as 10 billion rocks and sent them into an orbit that intersected with Earth and Earth's moon. "Some of these rocks will eventually land on the moon as Venusian meteorites," said Cabot, a Yale graduate student and lead author of the study.

Cabot said catastrophic impacts such as these only happen every hundred million years or so -- and occurred more frequently billions of years ago.

"The moon offers safe keeping for these ancient rocks," Cabot said. "Anything from Venus that landed on Earth is probably buried very deep, due to geological activity. These rocks would be much better preserved on the moon."

Many scientists believe that Venus might have had an Earth-like atmosphere as recently as 700 million years ago. After that, Venus experienced a runaway greenhouse effect and developed its current climate. The Venusian atmosphere is so thick today that no rocks could possibly escape after an impact with an asteroid or comet, Cabot said.

Laughlin and Cabot cited two factors supporting their theory. The first is that asteroids hitting Venus are usually going faster than those that hit Earth, launching even more material. The second is that a huge fraction of the ejected material from Venus would have come close to Earth and the moon.

"There is a commensurability between the orbits of Venus and Earth that provides a ready route for rocks blasted off Venus to travel to Earth's vicinity," said Laughlin, who is professor of astronomy and astrophysics at Yale. "The moon's gravity then aids in sweeping up some of these Venusian arrivals."

Upcoming missions to the moon could give Cabot and Laughlin their answer soon. The researchers said NASA's Artemis program is the perfect opportunity to collect and analyze unprecedented amounts of lunar soil.

Laughlin said there are several standard chemical analyses that can pinpoint the origin of moon rocks, including any that came from Venus. Different ratios of specific elements and isotopes offer a kind of fingerprint for each planet in the solar system.

"An ancient fragment of Venus would contain a wealth of information," Laughlin said. "Venus' history is closely tied to important topics in planetary science, including the past influx of asteroids and comets, atmospheric histories of the inner planets, and the abundance of liquid water."

A team of psychologists at the Universities of Sussex and Portsmouth have purr-fected the art of building a bond with cats.

The new study 'The role of cat eye narrowing movements in cat-human communication', published online in the Nature journal Scientific Reports, has shown for the first time that it is possible to build rapport with a cat by using an eye narrowing technique with them. This eye narrowing action by humans generates something popularly known as a cat smile - the so called "slow blink" - and seems to make the human more attractive to the cat. Eye narrowing movements in cats have some parallels with the genuine smile in humans (the Duchenne smile), as well as eye narrowing movements given in positive situations in some other species.

The team, led by Dr Tasmin Humphrey and Professor Karen McComb, animal behaviour scientists at the University of Sussex, undertook two experiments. The first revealed that cats are more likely to slow blink at their owners after their owners have slow blinked at them, compared to when they don't interact at all. The second experiment, this time with a researcher from the psychology team, rather than the owner, found that the cats were more likely to approach the experimenter's outstretched hand after they'd slow blinked at the cat, compared to when they had adopted a neutral expression. Taken together, the study shows that this slow blinking technique can provide a form of positive communication between cats and humans.

The study found:

· Cats were more likely to slow blink at their owners if their owners had slowed blinked at them, compared to when the owner was present in the room but not delivering a slow blink stimulus.

· Cats were more likely to slow blink when an unfamiliar experimenter slow blinked at them, compared to when they had maintained a neutral expression.

· Cats preferred to approach an experimenter after they had slow blinked at the cat than if they had maintained a neutral expression.

Professor Karen McComb, from the School of Psychology at the University of Sussex, who supervised the work, said: "As someone who has both studied animal behaviour and is a cat owner, it's great to be able to show that cats and humans can communicate in this way. It's something that many cat owners had already suspected, so it's exciting to have found evidence for it.

"This study is the first to experimentally investigate the role of slow blinking in cat-human communication. And it is something you can try yourself with your own cat at home, or with cats you meet in the street. It's a great way of enhancing the bond you have with cats. Try narrowing your eyes at them as you would in a relaxed smile, followed by closing your eyes for a couple of seconds. You'll find they respond in the same way themselves and you can start a sort of conversation."

Dr Tasmin Humphrey, a PhD student in the School of Psychology at the University of Sussex during the work, who was the first author of the study said: "Understanding positive ways in which cats and humans interact can enhance public understanding of cats, improve feline welfare, and tell us more about the socio-cognitive abilities of this under-studied species.

"Our findings could potentially be used to assess the welfare of cats in a variety of settings, including veterinary practices and shelters.

"In terms of why cats behave in this way, it could be argued that cats developed the slow blink behaviours because humans perceived slow blinking as positive. Cats may have learned that humans reward them for responding to slow blinking. It is also possible that slow blinking in cats began as a way to interrupt an unbroken stare, which is potentially threatening in social interaction.

Dr Leanne Proops at University of Portsmouth who co-supervised the work said: "It's definitely not easy to study natural cat behaviour so these results provide a rare insight in to the world of cat-human communication."

How the experiments worked

Two experiments were conducted to explore the significance of the slow blink in cat-human communication. The first experiment included a total of 21 cats from 14 different households. Fourteen different owners participated in experiment 1. Ten of the cats were male and 11 of the cats were female, with cat age ranging from an estimated 0.45-16 years. The experiments took place in each cat's home. The psychologist advised the cat's owner on how to slow blink. Once the cat had settled down in one place, the psychologist asked the owner to either sit approximately 1 m away from the cat.

Experiment 2 included a total of 24 additional cats. Twelve cats were male and 12 cats were female, with cat age ranging from an estimated 1-17 years old. The cats included in the final analyses were from 8 different households. In this experiment, the researcher, who was unfamiliar to the cat, either slow blinked at the cat or adopted a neutral face without direct eye contact. This experiment also tested which context the cats preferred to approach the unfamiliar experimenter, by them offering the cat a flat hand with palm faced upwards whilst sat or crouched directly opposite the cat. Both experiments were video recorded.

Cat psychology - the existing context

In the new paper, the authors provide some context for their findings. The psychology of cats hasn't been studied as extensively as dogs, but what is already known includes:

· That cats have been shown to attract and manipulate human attention effectively through 'solicitation purring'.

· That cats can discriminate their name from other words, even when unfamiliar humans are calling.

· That cats may be sensitive to human emotional cues, and will rub or butt their head against a an owner who feels sad.

'The role of cat eye narrowing movements in cat-human communication' by Tasmin Humphrey, Leanne Proops, Jemma Forman, Rebecca Spooner and Karen McComb published in Scientific Reports is open access, Link to the paper here: https://www.nature.com/articles/s41598-020-73426-0

DALLAS - Oct. 7, 2020 - Endocannabinoids, signaling molecules produced in the body that share features with chemicals found in marijuana, can shut down genes needed for some pathogenic intestinal bacteria to colonize, multiply, and cause disease, new research led by UT Southwestern scientists shows.

The findings, published online today in Cell, could help explain why the cannabis plant - the most potent part of which is marijuana - can lessen the symptoms of various bowel conditions and may eventually lead to new ways to fight gastrointestinal infections.

Discovered in 1992, endocannabinoids are lipid-based neurotransmitters that play a variety of roles in the body, including regulating immunity, appetite, and mood. Cannabis and its derivatives have long been used to relieve chronic gastrointestinal conditions, including irritable bowel syndrome and inflammatory bowel disease. Studies have shown that dysregulation of the body's endocannabinoid system can lead to intestinal inflammation and affect the makeup of gut microbiota, the population of different bacterial species that inhabit the digestive tract.

However, study leader Vanessa Sperandio, Ph.D., professor of microbiology and biochemistry at UTSW, says it's been unknown whether endocannabinoids affect susceptibility to pathogenic gastrointestinal infections.

To help answer this question, Sperandio and her colleagues worked with mice genetically altered to overproduce the potent mammalian endocannabinoid 2-arachidonoyl glycerol (2-AG) in various organs, including the intestines. When the researchers infected these animals and their unmodified littermates with Citrobacter rodentium, a bacterial pathogen that attacks the colon and causes marked inflammation and diarrhea, the mutant mice developed only mild symptoms compared with the more extreme gastrointestinal distress exhibited by their littermates. Examination of the mutant animals' colons showed far lower inflammation and signs of infection. These mice also had significantly lower fecal loads of C. rodentium bacteria and cleared their infection days faster than their unmodified littermates. Treating genetically unmodified animals with a drug that raised levels of 2-AG in the intestines produced similar positive effects.

Sperandio's team found that increased levels of 2-AG could also attenuate Salmonella typhimurium infections in mice and impede enterohemorrhagic Escherichia coli - a particularly dangerous gastrointestinal bacteria that infects humans - in order to express the virulence traits needed for a successful infection.

Conversely, when the researchers treated mammalian cells in petri dishes with tetrahydrolipstatin, a Food and Drug Administration-approved compound sold commercially as Alli that inhibits 2-AG production, they became more susceptible to the bacterial pathogens.

Further experiments showed that 2-AG exerted these effects on C. rodentium, S. typhimurium, and E. coli by blocking a bacterial receptor known as QseC. When this receptor senses the host signaling molecules epinephrine and norepinephrine, it triggers a molecular cascade necessary to establish infection. Plugging this receptor with 2-AG prevents this virulence program from activating, Sperandio explains, helping to protect against infection.

Sperandio notes that these findings could help explain some of the effects of cannabis use on inflammatory bowel conditions. Although studies have shown that cannabis can lower inflammation, recent research has shown that these conditions also tend to have a bacterial component that might be positively affected by plant cannabinoids.

In addition, cannabis compounds or synthetic derivatives could eventually help patients kick intestinal bacterial infections without antibiotics. This could be particularly useful for infections caused by enterohemorrhagic Escherichia coli, Sperandio says, which produces a deadly toxin when it's treated with antibiotics, rendering these drugs not only counterproductive but extremely dangerous. Because many virulent bacteria that colonize areas elsewhere in the body also have the QseC receptor, she adds, this strategy could be used more broadly to fight a variety of infections.

"By harnessing the power of natural compounds produced in the body and in plants," she says, "we may eventually treat infections in a whole new way."