Brain

As the body goes about its daily business, molecules called neurotransmitters control the level of electrical activity within the brain. Interacting with protein receptors nestled in the membrane that makes up the outer border of a neuron, neurotransmitters open and close portals that control the flow of ions in and out of the cell.

Gamma-aminobutyric acid, or GABA, dominates as one of the most important inhibitory neurotransmitters in the brain. Its primary role is to calm brain activity, lowering the number of signals firing in the brain in balance with the activity of other neurotransmitters that ramp up brain activity. (It's even sold as a nutritional supplement to promote calm and improve sleep.)

When GABA is unable to inhibit brain signaling, the imbalance in activity can lead to a number of health issues including anxiety or mood disorders, increased pain, muscle spasms and, in extreme cases, even epilepsy.

In a study published in Nature on June 17, scientists at USC Dornsife College of Letters, Arts and Sciences and the Bridge Institute at the USC Michelson Center for Convergent Bioscience figured out how GABA interacts with a key protein receptor called GABAB.

The study, done in collaboration with researchers at Stanford University, the Stanford Linear Accelerator Center and the Université de Montpellier in France, paints a clear picture of how GABA changes the shape of GABAB and reveal a clear target for new drugs.

Ultra-high definition views of a shape-shifter

The researchers used cryo-electron microscopy, or cryo-EM, to capture never-before-seen detailed snapshots of the GABAB receptor protein twisting and contorting as it interacts with GABA.

The GABAB receptor protein rests across the cellular membrane of neurons and is composed of two subunits with similar shapes: GB1, which recognizes GABA, and GB2, which relays the signal from GB1 into the cell's interior.

The cryo-EM images provide blueprints of how, as GABA interacts with GB1, a ripple effect moves through the entire protein until a cavity opens in the part of GB2 that faces inside the cell. Once revealed, this cavity in GB2 can interact with and activate proteins within the cell that control the neuron's activity.

The three-dimensional structural images offer promise for improved therapies for neurological disorders, according to Vadim Cherezov, professor of chemistry at USC Dornsife and a corresponding author on the study. "These blueprints can be used to design new therapeutic drugs that could affect different conformational states and thus act more precisely."

Equally important if not more so, the images also reveal a critical location on the GABAB receptor protein, where GB1 and GB2 meet within the cell membrane when the receptor is activated. Previously unknown, this GB1-GB2 interface is a prime target for a type of drug called a PAM (short for positive allosteric modulator).

PAMs offer promise for the development of new therapeutic drugs because they don't replace the action of naturally occurring molecules such as GABA but rather fine-tune how the receptor behaves, leading to fewer side-effects, Cherezov said.

"There are many therapeutic areas in which targeting the GABAB receptor protein could be beneficial; however, such direct interventions may come with significant side-effects," he said. "Developments of PAMs facilitated by our structure images could lead to a new generation of safer drugs targeting this receptor."

Quantum communication--where information is sent through particles, typically entangled photons--has the potential to become the ultimate secure communication channel. Not only is it nearly impossible to eavesdrop on quantum communication, those who try will also leave evidence of their indiscretions.

However, sending quantum information via photons over traditional channels, such as fiber-optic lines, is difficult: the photons carrying the information are often corrupted or lost, making the signals weak or incoherent. Oftentimes a message must be sent several times to ensure that it went through.

In a new paper, scientists with the Pritzker School of Molecular Engineering (PME) at the University of Chicago have demonstrated a new quantum communication technique that bypasses these channels altogether. By linking two communication nodes with a channel, they show that this new technique can send information quantum-mechanically between the nodes--without ever occupying the linking channel.

The research, led by Prof. Andrew Cleland and published June 17 in the journal Physical Review Letters, takes advantage of the spooky quantum phenomenon of entanglement between the two nodes and shows a potential new direction for the future of quantum communication.

The research joins a second recently published paper, where Cleland's group entangled two phonons--the quantum particles of sound--for the first time, opening the door to potential new technologies.

"Both papers represent a new way of approaching quantum technology," said Cleland, the John A. MacLean Sr. Professor of Molecular Engineering at Pritzker Molecular Engineering and a senior scientist at Argonne National Laboratory. "We're excited about what these results might mean for the future of quantum communication and solid-state quantum systems."

Ghostly quantum communication

Entangled photons and phonons defy intuition: these particles can be quantum-mechanically entangled, an entanglement that can survive over large distances. A change in one particle then spookily elicits a change in the other. Quantum communication takes advantage of this phenomenon by encoding information in the particles.

Cleland wanted to find a method to send quantum information without losing it in the transmission. He and his team, including PME graduate student Hung-Shen Chang, developed a system that entangled two communication nodes using microwave photons--the same photons used in your cell phone--through a microwave cable. For this experiment, they used a microwave cable about a meter in length. By turning the system on and off in a controlled manner, they were able to quantum-entangle the two nodes and send information between them--without ever having to send photons through the cable.

"We transferred information over a one-meter cable without sending any photons to do this, a pretty spooky and unusual achievement," Cleland said. "In principle, this would also work over a much longer distance. It would be much faster and more efficient than systems that send photons through fiber-optic channels."

Though the system has limitations--it must be kept very cold, at temperatures a few degrees above absolute zero--it could potentially work at room temperature with atoms instead of photons. But Cleland's system provides more control, and he and his team are conducting experiments that would entangle several photons together in a more complicated state.

Entangling phonons with the same technique

Entangled particles aren't just limited to photons or atoms, however. In a second paper published June 12 in the journal Physical Review X, Cleland and his team entangled two phonons--the quantum particle of sound--for the first time ever.

Using a system built to communicate with phonons, similar to the photon quantum communication system, the team, including former postdoctoral fellow Audrey Bienfait, entangled two microwave phonons (which have roughly a million times higher pitch than can be heard with the human ear).

Once the phonons were entangled, the team used one of the phonons as a "herald," which was used to affect how their quantum system used the other phonon. The herald allowed the team to perform a so-called "quantum eraser" experiment, in which information is erased from a measurement, even after the measurement has been completed.

Though phonons have a lot of disadvantages over photons--for example, they tend to be shorter-lived--they interact strongly with a number of solid-state quantum systems that may not interact strongly with photons. Phonons could provide a better way to couple to these systems

"It opens up a new window in what you can do with quantum systems, perhaps similar to the way gravitational wave detectors, that also use mechanical motion, have opened a new telescope on the universe," Cleland said.

A long-sought-after black phosphous-structured (BP) nitrogen was synthesized by an international team co-led by Dr. Ho-Kwang Mao and Dr. Huiyang Gou from the Center for High Pressure Science and Technology Advanced Research (HPSTAR) and Prof. Yansun Yao from the University of Saskatchewan. This finding provides a firm base for exploring new type of high-energy-density nitrogen and a new direction of two-dimensional nitrogen. The results were recently published in Science Advances.

Graphene, or a single layer of graphite, has a set of novel properties that have attracted tremendous attention since its discovery. Nitrogen is the next neighbor to carbon in the periodic table of elements, so it is natural to question whether nitrogen can form a 2D material similar to graphene. It is not easy to imagine such a nitrogen layer because nitrogen has one more electron than carbon, overwhelming the bonding requirement of graphene. However, all elements in the VA group bar nitrogen do possess allotropes with layered structures similar to graphite but with the layers being buckled (Figure 1A). Phosphorene is a typical 2D material derived from the buckled honeycomb layers of black phosphorus. It exhibits a number of unusual electronic, mechanical, optical, and transport properties with great potential as a prototypical next-generation 2D material. Finding a BP-structured nitrogen means the synthesis of a nitrogen-based 2D material, or nitrogene, may become possible.

The rule of thumb for structural changes at high pressure is that elements at high pressure behave like the elements below them in the periodic table at lower pressures. As the first element of the VA group, nitrogen is right above phosphorus. Theoretical calculations have predicted the formation of BP-structured nitrogen at high pressure. However, it is much more challenging to transform nitrogen into a BP structure than the other VA elements because nitrogen forms N2 molecules with extremely strong triple chemical bonds. Even though nitrogen has been studied at pressures exceeding one million atmosphere (100 GPa), BP-structured nitrogen has never been reported until now.

"Analogous to the black, white, and red phosphorus allotropes, which have similar energies and can be mutually transformed, single-bonded nitrogen at high pressure may also have multiple polymorphs that are very close in energy. Although BP-structured nitrogen is not calculated to be the allotrope with the lowest energy, we think it may be synthesized as a metastable phase at particular pressure-temperature conditions," said Dr. Huiyang Gou, a co-team leader at the Center for High Pressure Science and Technology Advanced Research (HPSTAR) in Beijing.

"Our molecular dynamic simulation indicates that BP-structured nitrogen becomes energetically more favorable when the temperature is raised, implying the possibility of synthesizing BP-structured nitrogen at high-pressure and high-temperature conditions." said Prof. Yansun Yao, from the University of Saskatchewan.

The team used diamond anvil cell apparatus to exert formidable pressure onto molecular nitrogen; squeezing a tiny nitrogen sample between two opposite sharp diamond tips (Figure 1B), and subjecting it to very high temperatures by high-power laser heating. They explored a large pressure range from 1.2 to 1.9 million times normal atmospheric pressure, and saw the formation of a new nitrogen phase at approximately 1.5 million times normal atmospheric pressure and 1,900 degrees Celsius. The BP structure was identified using synchrotron-based single-crystal X-ray diffraction (XRD) techniques (Figure 1C), Raman spectroscopy (Figure 1D), and theoretical calculation. The new material exhibits an extraordinary set of optical properties associated with the anisotropy of the buckled layers, in particular, colossal Raman intensity compared to other nitrogen phases. The reason for the long-term absence of BP-structured nitrogen in high-pressure experiments is also explained through theoretical calculations. The BP-structured nitrogen transforms back to N2 gas when the pressure is lowered. Future studies are desirable to obtain metastable BP-structured nitrogen at ambient conditions.

"The discovery of BP-structured nitrogen is a typical showcase demonstrating the importance of fundamental scientific research at extreme conditions," added Dr. Ho-kwang Mao, director of HPSTAR. "Proving the existence of a material is the very first and essential step towards applications, which may demand years or even decades of continued research efforts."

A research team led by Dr Chaogu Zheng from the School of Biological Sciences at the University of Hong Kong (HKU), in collaboration with a team led by Professor Martin Chalfie (2008 Nobel Laureate in Chemistry) from the Department of Biological Sciences at Columbia University, recently discovered an unexpected role of the heat shock proteins (HSPs), also known as the molecular chaperones, during neuronal differentiation, which refers to the process a neuron takes to acquire its shape and function. HSPs are mostly known to protect cells from various stresses, e.g. extreme temperatures, toxins, and mechanical damage, and to safeguard tissue development. This new study, however, suggests that the Hsps can also play an inhibitory role in neuronal differentiation by destabilizing the cytoskeleton of the neurons. The research findings were recently published in a leading international journal in the developmental biology - Development.

Protein quality control is important for normal development in human cells, and its dysregulation leads to a range of neurodevelopmental disorders. Inside cells, the Hsps and other chaperones promote protein folding and stability, while the ubiquitination-proteasome system (UPS) targets proteins for degradation. The HSPs and UPS pathways often collaborate to eliminate irreparable proteins in some cellular contexts, but their interaction in developing neurons is not well understood. Using neurons from a model organism called Caenorhabditis elegans, which can be easily genetically manipulated, the research team discovered that when the UPS system is compromised in genetic mutants, a major part of the cytoskeleton called microtubules is destabilized, leading to defects in the axonal growth (axons are the projections of neurons). Surprisingly, through a genetic screen, the team found that deleting the HSPs and co-chaperones can fully rescue the defects caused by the compromised UPS, suggesting that the two systems counter each other during development.

Furthermore, a protein kinase called DLK-1 was found to be stabilized by the HSPs and degraded by the UPS. The overabundance of DLK-1 caused instable microtubules and neuronal growth defects. Thus, by regulating the same target proteins, HSPs and UPS can fine-tune the level of critical signaling molecules and create a tightly controlled balance between protein stability and degradation. The discovery of this mechanisms can help understand the molecular basis of neurodevelopmental diseases, nerve regeneration, and neurodegenerative diseases.

"This research identifies a previously underappreciated role of HSPs in neuronal development and suggests that HSPs may not be always protective of cellular morphology and functions," said Dr Zheng. At the same time, this research also opens up a new direction to understand the antagonism between the HSPs and the UPS system in maintaining a balance between protein stabilization and turnover. In the further, Dr Zheng suggests the research will be focused on identifying the common targets of the two HSPs and UPS pathways, which will be the critical control point of not only neuronal development but also neuronal regeneration. Dr Zheng envisions that a complete understanding of the relationship between chaperoning and degradation of proteins can help identify the key therapeutic targets of many neurological diseases.

By discovering a trick the hepatitis C virus uses to evade the immune system, scientists have identified a new antiviral defence system that could be used to treat many virus infections, according to new research published today in eLife.

Viruses have many strategies to avoid immune system defenses. They often do this by hijacking the immune system's own proteins. One immune protein that is frequently targeted by viruses, including HIV, hepatitis C, and the SARS coronavirus, is called cyclophilin A (CypA). Understanding how CypA is used by viruses could help scientists develop drugs that work against all of them, including the SARS-CoV-2 virus causing the COVID-19 pandemic.

"Previously, clinical trials have shown that blocking CypA reduces the ability of the hepatitis C virus to replicate and boosts the immune response," explains lead author Che Colpitts, Assistant Professor of Biomedical and Molecular Sciences at Queen's University, Kingston, Canada. "We set out to understand how CypA helps hepatitis C evade the immune system."

In the experiments, the team used hepatitis C-infected human liver cancer cells with and without a functioning innate immune system. The innate immune system scans the body for potential threats such as viruses or bacteria and triggers a response. The scientists used a tool called a short hairpin RNA to selectively silence CypA and found that this stopped the virus from replicating only in the liver cells with a functioning innate immune system. They also showed that drugs called cyclophilin inhibitors help block the virus from co-opting CypA and prevent it from multiplying.

CypA is known to attach to an immune protein called protein kinase R (PKR), affecting its ability to detect viruses. So, the team used a gene-editing tool called CRISPR/Cas9 to cut out the gene for PKR in human liver cells with a working innate immune system. In cells without PKR, the cyclophilin inhibitors were less able to stop the virus from reproducing. This happened because PKR was not there to identify the virus and trigger antiviral defenses.

"These findings reveal a new antiviral defence mechanism that suppresses virus growth," says senior author Greg Towers, Professor of Molecular Virology at University College London, UK. "This opens the door for the development of CypA-targeting antiviral drugs that can be used against many currently untreatable viruses."

While it's only about a 10-kilometer stretch, Juno Beach is home to one of the largest aggregations of nesting green sea turtles (Chelonia mydas) in Florida and is one of the highest-density nesting beaches in the state. Although this high-profile turtle population has routinely been monitored for nest counts since 1989, an in-depth health assessment of these turtles has never been conducted.

Researchers from Florida Atlantic University's Harbor Branch Oceanographic Institute and Loggerhead Marinelife Center have conducted the most comprehensive health assessment for a green turtle rookery in the world to date. Findings from the study provide critical insights into various aspects of physiology, biology, and herpesvirus epidemiology of this nesting population and are especially timely as the world observes "Sea Turtle Day."

Results, recently published in the journal Endangered Species Research, are hopeful for this population of green sea turtles in southeastern Florida and offer important data on the profile of health for future comparative investigations.

"Effective conservation measures cannot take place unless the animals we are trying to protect are healthy," said Annie Page-Karjian, D.V.M., Ph.D., lead author, assistant research professor and clinical veterinarian at FAU's Harbor Branch. "Chronological and longitudinal studies of biology, physiology, and overall health in both free-ranging and captive populations are critical for supporting large-scale efforts to promote sea turtle population recovery."

A total of 4,343 green turtle nests were documented on Juno Beach in 2017, which was the busiest nesting year on record for this beach. For the study, researchers collected blood samples from 60 female green turtles that nested on Juno Beach in 2017. They evaluated a broad suite of biological and health data, including measures of reproductive success, morphometrics, hematology, plasma chemistry, plasma protein fractions, haptoglobin, corticosterone, and measures of oxidative stress, antioxidative capacity, and innate immunity. They also tested for two herpesviruses of green turtles, ChHV5 and ChHV6, which are implicated in fibro-papillomatosis (FP) and respiratory and skin disease, respectively. FP is a debilitating disease of sea turtles characterized by neoplastic growths on the skin, shell, and/or internal organs.

Results showed that all 60 turtles included in the study were in good body condition with no external FP tumors. Five of the 60 turtles (8 percent) tested positive for ChHV5 and all turtles were negative for ChHV6. Of the 41 turtles tested for antibodies to ChHV5 and ChHV6, 29 percent and 15 percent tested positive, respectively, and 10 percent tested positive for antibodies to both viruses. Notably, there were no statistically significant differences between health variables for nesting turtles that tested positive for ChHV5 DNA versus those that tested negative; and also no differences between turtles that tested positive for ChHV5 or ChHV6 antibodies and those that did not. Findings from the study suggest that these viruses are endemically stable in Florida's adult green sea turtles.

Researchers differentiated between previous viral infection versus recent infection/reactivation, and evaluated the results alongside health analytes to understand whether either infection state was associated with detectable physiological changes.

"The fitness of the turtles examined for this study is likely representative of the health of the ecosystems in which they forage and the oceanic corridors through which they migrate," said Page-Karjian. "As human activities continue to affect sea turtle population recovery, these comprehensive baseline data from our study will provide a valuable resource for evaluating the impacts of various stressors such as habitat degradation on the population over time and will help inform wildlife and environmental policy management."

Green turtles are the second most common sea turtle species to nest on the coast of Florida, after loggerhead turtles (Caretta caretta). Sea turtles are considered to be sentinel species of environmental health, whereby sea turtle health is thought to reflect the health of the ecosystems they inhabit. Thus, examining sea turtle health is an important component of any coastal ecosystem health survey that includes sea turtle developmental, foraging, and/or nesting habitat(s).

Conservation threats to sea turtles in Florida are numerous, and include habitat encroachment and pollution, illegal harvesting, artificial beach lighting and coastal armoring, and human interactions such as entanglement, hook ingestion, and boat strike trauma. Diseases, including FP, also directly threaten sea turtle conservation.

Scientists at the University of Sydney have adapted techniques from autonomous vehicles and robotics to efficiently assess the performance of quantum devices, an important process to help stabilise the emerging technologies.

The innovative approach has been shown experimentally to outperform simplistic characterisation of these environments by a factor of three, with a much higher result for more complex simulated environments.

"Using this approach, we can map the 'noise' causing performance variations across quantum devices at least three times as quickly as a brute-force approach," said lead author Riddhi Gupta, a PhD student in the School of Physics. "Rapidly assessing the noise environment can help us improve the overall stability of quantum devices."

The research has been published in Nature partner journal Quantum Information.

Quantum computing is still in its early stages of development yet promises to revolutionise technology by solving problems beyond the scope of classical computing.

One of the barriers to develop these systems to practical scale is overcoming the imperfections of hardware. The basic units of quantum technology - quantum bits, or qubits - are highly sensitive to disturbance from their environments, such as electromagnetic 'noise', and exhibit performance variations that reduce their usefulness.

Ms Gupta, also part of the ARC Centre of Excellence for Engineered Quantum Systems, has taken techniques from classical estimation used in robotics and adapted them to improve hardware performance. This is achieved through the efficient automation of processes that map both the environment of and performance variations across large quantum devices.

"Our idea was to adapt algorithms used in robotics that map the environment and place an object relative to other objects in their estimated terrain," she said. "We effectively use some qubits in the device as sensors to help understand the classical terrain in which other qubits are processing information."

In robotics, machines rely on simultaneous localisation and mapping, or SLAM, algorithms. Devices like robotic vacuum cleaners are continuously mapping their environments then estimating their location within that environment in order to move.

The difficulty with adapting SLAM algorithms to quantum systems is that if you measure, or characterise, the performance of a single qubit, you destroy its quantum information.

What Ms Gupta has done is develop an adaptive algorithm that measures the performance of one qubit and uses that information to estimate the capabilities of nearby qubits.

"We have called this 'Noise Mapping for Quantum Architectures'. Rather than estimate the classical environment for each and every qubit, we are able to automate the process, reducing the number of measurements and qubits required, which speeds up the whole process," Ms Gupta said.

Dr Cornelius Hempel, whose experimental team provided Ms Gupta with data from experiments on a one-dimensional string of trapped ions, said he was pleased to see a threefold improvement even in the mapping of such a small quantum system.

"However, when Riddhi modelled this process in a larger and more complex system, the improvement in speed was as high as twentyfold. This is a great result given the future of quantum processing is in larger devices," he said.

Ms Gupta's supervisor is Professor Michael J. Biercuk, founder of quantum technology company Q-CTRL and director of the University of Sydney Quantum Control Laboratory.

He said: "This work is an exciting demonstration that state-of-the-art knowledge in robotics can directly shape the future of quantum computing. This was a first step to unify concepts from these two fields, and we see a very bright future for the continued development of quantum control engineering."

The bitter gourd (Momordica charantia) is a summer vegetable that graces the tables of many homes and restaurants in Asia. In Okinawa and Kyushu, the southern islands of Japan, the bitter gourds grow easily and have long been said to have many health benefits. The bitter gourds are packed with vitamin C, vitamin A, folate, minerals, carotenes and catechins. It is thought to ward off the feeling of sluggishness that can accompany the summer heat and humidity.

The bitter gourd is healthy to eat, and is traditionally said to have medicinal properties. There has been research into its effectiveness in lowering blood sugar. Associate Professor Hideo Matsumura of Shinshu University and an international team elucidated the genome sequence of the bitter gourd to scientifically look into developing strains that exhibit the medicinal claims and create a better product. Historically, it has been cultivated for the unique bitter taste preferred by the region, but demand is growing for a better universal product. For that purpose, it was necessary to clarify the genetic background of the bitter gourd.

Domestication occurs when humans actively modify traits of organisms. Most domesticated plants show the significant phenotypic and genotypic differences from wild strains upon the divergence between wild and cultivar groups. However, the bitter gourd showed its divergence after it had domesticated when regional cultivar groups reflected consumer preferences in different areas, to the South Asia and Southeast Asia type.

The group sequenced the genome of 60 bitter gourd strains: 18 wild accessions, 42 cultivar strains and an outgroup (Momordica cochinchinensis) from around the world. This process of sequencing and comparisons revealed that the bitter gourd came from the wild strain in South Asia 6000 years ago. Then, the Southeastern strain diverged from the South Asian cultivar strain 800 years ago, creating the large phenotypic divergence.

Two-stage patterns of quantitative trait evolution has also been observed in maize, watermelon and tomato. However, the bitter gourd may provide a valuable nonclassic model of domestication of the intermittent weaker selection and polygenic genetic architecture that precludes the identification of strong single candidate genes. Also, according to the low divergence between the wild and cultivars in the genomic region containing gynoecious locus, directional artificial selection for sex ratio cannot overwhelm the force of balancing selection in nature.

This study is also unique in that the group reported on the chromosome-level genome assembly and genomic investigation of non-classic domestication model instead of the usual selective sweep of newly mutated Mendelian genes.

What happens to teenagers whose parents are overbearing? A new longitudinal study sought to determine the long-term impact on youth of parenting that is psychologically controlling. Although the study did not establish causation, it found that overbearing and overcontrolling tactics by parents when children were 13 years old were associated with difficulties in social relationships and educational attainment by the time the teens reached age 32.

The findings, from researchers at the University of Virginia, are published in Child Development, a journal of the Society for Research in Child Development.

"Parents, educators, and clinicians should be aware of how parents' attempts to control teens may actually stunt their progress," says Emily Loeb, postdoctoral researcher at the University of Virginia, who was the lead author on the study. "This style of parenting likely creates more than a temporary setback for adolescent development because it interferes with the key task of developing autonomy at a critical period."

Past research has identified psychological control as a problematic parenting behavior. Parents attempt to control their children in this way through intrusive and harshly manipulative means (e.g., withdrawing love and affection when the parent is angry at the child, making the child feel guilty for upsetting the parent). Children whose parents use this tactic tend to have problems such as lower grades and lower self-esteem, likely because the children are discouraged from asserting themselves and gaining independence.

In this study, which examined perceived psychological control earlier in adolescent development than previous work, researchers followed 184 youth annually from ages 13 to 32. The youth, from urban and suburban areas in the Southeastern United States, came from a variety of socioeconomic backgrounds. About half of the group was male and half female, and 42% identified themselves as members of minority racial/ethnic groups. The study also considered family income, gender, and grade point average at age 13.

Researchers asked the participants fill out questionnaires about themselves, their parents, and in adulthood, their relationship status and level of education. They also collected information from each youth's peers about how well liked the teen was in school, and they observed videos of each youth interacting with his or her closest friend and later in adulthood, interacting with his or her romantic partner.

The study found that having overbearing and overcontrolling parents at age 13 was associated with less supportive romantic relationships for those who were in relationships by age 27, a lower likelihood of being in a relationship by age 32, and lower educational attainment by age 32. These outcomes were explained largely by problems at ages 15 to 16, including that teens were less psychologically mature and were less liked by their peers.

"Even though parents routinely attempt to guide their children toward successful adaptation, overcontrolling parenting in adolescence has the potential to impede development in a fundamental way that's not easy to repair," according to Joseph Allen, Hugh Kelly Professor of Psychology at the University of Virginia, who coauthored the study.

Light exerts a certain amount of pressure onto a body: sun sails could thus power space probes in the future. However, when light particles (photons) hit an individual molecule and knock out an electron, the molecule flies toward the light source. Atomic physicists at Goethe University have now observed this for the first time, confirming a 90 year-old theory.

As early as the 16th century, the great scholar Johannes Kepler postulated that sunlight exerted a certain pressure, as the tail of the comets he observed consistently pointed away from the sun. In 2010 the Japanese space probe Ikaros used a sun sail for the first time in order to use the power of sunlight to gain a little speed.

Physically and intuitively, the pressure of light or radiation can be explained by the particle characteristic of light: light particles (photons) strike the atoms of a body and transfer a portion of their own momentum (mass times speed) onto that body, which thus becomes faster.

However, when in the 20th century physicists studied this momentum transfer in the laboratory during experiments on photons of certain wavelengths which knocked individual electrons out of atoms, they were met by a surprising phenomenon: the momentum of the ejected electron was greater than that of the photon that struck it. This is actually impossible - since Isaac Newton it has been known that within a system, for every force there must exist an equal but opposite force: the recoil, so to speak. For this reason, the Munich scientist Arnold Sommerfeld concluded in 1930 that the additional momentum of the ejected electron must come from the atom it left. This atom must fly in the opposite direction; in other words, toward the light source. However, this was impossible to measure with the instruments available at that time.

Ninety years later the physicists in the team of doctoral student Sven Grundmann and Professor Reinhard Dörner from the Institute for Nuclear Physics have succeeded for the first time in measuring this effect using the COLTRIMS reaction microscope developed at Goethe University Frankfurt. To do so, they used X-rays at the accelerators DESY in Hamburg and ESRF in French Grenoble, in order to knock electrons out of helium and nitrogen molecules. They selected conditions that would require only one photon per electron. In the COLTRIMS reaction microscope, they were able to determine the momentum of the ejected electrons and the charged helium and nitrogen atoms - which are called ions - with unprecedented precision.

Professor Reinhard Dörner explains: "We were not only able to measure the ion's momentum, but also see where it came from - namely, from the recoil of the ejected electron. If photons in these collision experiments have low energy, the photon momentum can be neglected for theoretical modelling. With high photon energies, however, this leads to imprecision. In our experiments, we have now succeeded in determining the energy threshold for when the photon momentum may no longer be neglected. Our experimental breakthrough allows us to now pose many more questions, such as what changes when the energy is distributed between two or more photons."

AURORA, Colo. (June 15, 2020) - A national study measuring parental attitudes toward vaccinations found 6.1% were hesitant about routine childhood immunizations while nearly 26% were hesitant about the influenza vaccine.

"Our study provides the first national estimates of hesitancy about routine childhood and influenza vaccination among representative samples of U.S. parents of children, using a scale specifically developed and validated to assess vaccine hesitancy internationally," said the study's lead author Allison Kempe, MD, MPH, professor of pediatrics at the University of Colorado School of Medicine and director of ACCORDS which brings together investigators from across CU Anschutz Medical Campus to conduct research for real world impact.

The study was published today in the journal Pediatrics.

The investigators surveyed 2,176 parents and found 12% strongly agreed and 27% somewhat agreed they had concerns over serious side effects of both routine childhood and influenza vaccines. In contrast, 70% strongly agreed that routine vaccinations were effective versus only 26% for the influenza vaccine.

The researchers found those with less than a bachelor's degree more skeptical of vaccinations. Race and ethnicity didn't play a major role in these attitudes but Latino parents were less hesitant than white, non-Latino parents about getting vaccinated against influenza.

"The fact that one in eight parents are still concerned about vaccine safety for both childhood and influenza vaccinations is discouraging," said Kempe who practices at Children's Hospital Colorado. "But what is driving the hesitancy about the influenza vaccine is primarily doubts about its effectiveness."

In fact, the vaccine is not 100% effective in preventing influenza but, even in a year where there is not a good match between circulating strains and the vaccine, Kempe said it lessens the severity of the illness which kills between 10,000 and 60,000 Americans annually.

Last year, the World Health Organization (WHO) designated vaccine hesitancy as one of the ten leading threats to global health. In many countries, including the U.S., hesitancy about childhood vaccines has contributed to lower rates of childhood vaccination, with associated outbreaks of vaccine-preventable diseases, including pertussis, mumps and measles.

As of 2018-2019, just 57.9% of American children were vaccinated against influenza.

"That means in any given year more than 40% of children are not vaccinated against influenza," Kempe said. "We have already seen outbreaks of preventable diseases like measles and mumps. Low vaccination rates among children for influenza vaccine makes influenza seasons more severe for all portions of the population, since children are a major conduit of the disease to vulnerable parts of the population such as the elderly."

Understanding the reasons for hesitancy, Kempe said, will help providers develop interventions to combat vaccine hesitancy.

In addressing parents who are already hesitant about vaccines, the study suggests focusing on changing behavior rather than directly countering beliefs or attitudes.

Examples of this would include:

- Strong and presumptive, rather than open-ended, recommendations by a trusted provider.

- The use of standing orders.

- Making it easier to deliver vaccines via clinics and schools.

- Reminders and calls.

- Enacting preschool and school influenza vaccine requirements.

- Minimizing philosophic exemptions to the vaccine.

"There is evidence that communication techniques such as motivational interviewing can be helpful in convincing some hesitant parents to vaccinate in the primary care setting," the study said. "The use of social media interventions, some of which involve trained parents as advocates for vaccination within their own communities, has shown some effectiveness in overcoming hesitancy."

Kempe said the best way to counter hesitancy may be to prevent it from developing by starting conversations about vaccines before a baby is born.

"Ideally, we'd like to immunize parents against all the misinformation that is out there," she said.

The children of mothers with long-term depression have been found to be at higher risk of behavioural problems and poor development.

University of Queensland researchers analysed depression levels in 892 mothers and the development and behaviour of 978 children, using data from the Australian Longitudinal Study on Women's Health.

They compared maternal depression before, during and after pregnancy, and found duration was more influential than timing.

Researcher Dr Katrina Moss said the study found one in five women experienced depression once, while 11 per cent experienced a reoccurrence.

"The longer a mother suffered maternal depression, the worse the outcomes for the child," Dr Moss said.

"Mothers may worry that if they've been depressed during pregnancy then it's too late to do anything about it, but reducing depressive symptoms at any stage is better for them and their children.

"The earlier we can effectively detect and treat maternal depression, the better our chances of improving outcomes."

Dr Moss suggested screening for depression could start when couples begin planning a pregnancy, and continue through the perinatal period and early childhood.

"Maternal depression is a significant challenge for women, families and communities, and we need to look after women better at key times in their lives," she said.

Dr Moss said women experiencing depression should visit their GP and use supportive parent resources from organisations such as PANDA or the Gidget Foundation.

An international research team has conducted a field survey on two species of eel native to Japan and other organisms that share the same habitat, revealing for the first time in the world that these eels can act as comprehensive surrogate species for biodiversity conservation in freshwater rivers. It is hoped that conducting activities to restore and protect eel populations will contribute greatly to the recovery and conservation of freshwater ecosystems that have suffered a significant loss of biodiversity.

The team consisted of Researcher ITAKURA Hikaru (of Kobe University's Graduate School of Science, and a JSPS Overseas Research Fellow at the University of Maryland), Specially Appointed Researcher WAKIYA Ryoshiro (of The University of Tokyo), Dr. Matthew Gollock (of The Zoological Society of London) and Associate Professor KAIFU Kenzo (Chuo University).

The results of this research were published in the British scientific journal 'Scientific Reports' on May 29.

Main Points:

In a world-first, this research demonstrated that eels have the potential to be a comprehensive surrogate species for freshwater diversity conservation.

It is thought that efforts to restore eel populations through river environment restoration and conservation would be beneficial not only for the protection of eels but also for freshwater species as a whole.

Showed that two kinds of eel, the Japanese eel (Anguilla japonica) and the giant mottled eel (A. marmorata) (Figure 1), can serve as all three categories of surrogate species: umbrella, indicator and flagship (*1).

It was revealed that these two species of eel were found in all parts of rivers, from the upper to the lower reaches, making them the most widely distributed among freshwater organisms. In addition, stable isotope analysis (*2) indicated that these eel species are higher-order predators in freshwater ecosystems.

The researchers investigated the quantitative relationship between the eels and other diadromous migratory species (indicative of biodiversity), revealing that the presence of eels is a good sign of river-ocean connectivity, and consequently an indicator of freshwater biodiversity.

Research Background

Although freshwater covers only 2.3% of the Earth's surface, it provides diverse habitats that support a far greater number of species per area than terrestrial or marine ecosystems. However, at the same time freshwater ecosystems have suffered significant deterioration and loss of biodiversity due to the human populations concentrated around them. As a result far more freshwater species are in danger of extinction than species belonging to other ecosystems. One third of freshwater species have been classified as 'Endangered' in the International Union for Conservation of Nature (IUCN)'s Red List of Threatened Species.

It is challenging to monitor and manage all the species that make up these ecosystems in order to protect biodiversity. For this reason, it is thought that by focusing conservation efforts on one or a few species, we can understand the functions, resource dynamics and structures of the biological communities to which they belong. This knowledge can be used to manage and conserve biodiversity. These surrogate species are classified as umbrella, indicator or flagship species according to conservation goals. So far some large mammal and bird species have been proposed as surrogate species.

The two kinds of eel that were the subject of this study are catadromous, meaning that they are migratory species that spawn in the ocean and grow in rivers and coastal waters. Anguillid eels can be found almost worldwide (except for the polar areas); in the varied aquatic environments of 150 countries, including inner bays, and all parts of rivers from the source to mouth.

In this study, the researchers focused on the eels' unique life cycle and confirmed that they can serve as umbrella, indicator and flagship species. They propose that eels are a comprehensive surrogate species for the conservation of freshwater biodiversity.

Research Methodology

Eel and other freshwater organisms (fish and large crustaceans such as crab and shrimp) were collected from 78 sites spanning upstream to downstream regions in six rivers in Japan using an electric shocker (three mainland rivers in Kyushu and Honshu, and three rivers on Amami-Oshima island). The Japanese eel is mostly found in the mainland rivers, whereas the giant mottled eel largely inhabits Amami-Oshima's rivers. In order to determine these two species' suitability as indicator and umbrella species for biodiversity conservation, the distribution of the sampled eels and freshwater organisms in the rivers was analyzed and their trophic levels in the food web were researched. Furthermore, the researchers also investigated the quantitative relationship between the number of eels and the number of other migratory diadromous species (biodiversity), and the environmental factors affecting this. Japan is a mountainous country and there are many small, fast flowing rivers. It was predicted that the migratory species that travel between the sea and the rivers during their life cycles would be predominant in freshwater rivers' ecosystems. Therefore, a large number of migratory species was interpreted as an indicator of biodiversity.

The results from each of the field studies on Japanese eels and giant mottled eels showed that they were the most widely distributed of all freshwater species in river habitats. Japanese eels covered 87% of the study rivers in mainland Japan, whereas the giant mottled eel was found in 94% of the Amami Oshima rivers used in this study (Figure 2). Stable isotope analyses of the muscle tissue of eel and other freshwater organisms were carried out to estimate their trophic levels. The results showed that the mean trophic levels of eel species were greater than three which indicates that they are higher-order predators, and these values were significantly higher than those for other freshwater organisms (Figure 3). These results support the eels' potential as umbrella species and show that they require a diverse range of lower trophic level animals for food.

This study confirmed the presence of 48 species of freshwater organisms, including fish and crustaceans. As predicted, a total of 80% of these were migratory species (78% in Honshu/Kyushu and 91% on Amami Oshima island). Furthermore, there was a positive correlation between the number of Japanese eels or giant mottled eels and the number of other migratory species. A statistical model was used to investigate various environmental factors that may have an impact on both of these groups. The researchers found a strong negative correlation between the number of eels and other migratory species and the following two points; 'the distance of the study site from the sea' and the 'cumulative height of trans-river structures, such as dams or weirs, that species have to pass in order to get from the sea to the study site'. These factors have an impact on river-ocean connectivity for migratory species. In other words, these results imply that the positive correlation found between the number of eels and the number of other migratory species is probably an indirect relationship through river-ocean connectivity. In areas where river-ocean connectivity is high (i.e., it's easy for them to swim upstream), there will be greater numbers of eels and other migratory species. Conversely, if river-ocean connectivity is low, there will be fewer of these species. These results show that eels are an indicator of good river-ocean connectivity, and through this they are an indicator of biodiversity.

This research showed that trans-river structures have a negative impact on eels and other migratory species. It has been indicated that eels can climb such structures vertically, if the structures are wet. However, trans-river structures inhibit eel movement, moreover they have been shown to cause a decline in the numbers of many eel species. In this study, it was shown that even barriers under 1m high could have a negative impact on eel distribution. Previous studies have indicated that the habitat loss caused by these trans-river structures is a leading factor in the decline in eel numbers. Many other studies have reported that the distribution of other migratory species is limited by these structures in a similar way to eels. Eels are an indicator of river-ocean connectivity. It is hoped that improving and maintaining this connectivity for eels will greatly boost the biodiversity of freshwater ecosystems.

In 2016, IUCN decided upon the 'Promotion of Anguillid eels as flagship species for aquatic conservation'. This designation was based on the widespread decline of eel numbers, the effects of habitat deterioration and destruction, as well as eels' global distribution and their unique catadromous migration. As shown in this study, eels have the following important aspects that make them suitable as a flagship species; they are widely distributed, higher-order predators that are generally larger than other freshwater organisms, and are easily identifiable.

Looking at eels in terms of their importance ecologically, commercially and culturally, we can conclude that they have provided a diverse ecological service worldwide since ancient times. Eels are found almost all over the world, and have served as a source of food in various lands and eras. They have played roles in food cultures, in literature and art, in legends and belief systems. Therefore, the researchers concluded that eels have the ability to stir up great public awareness worldwide about environmental issues, which is connected to their value as a flagship species.

In conclusion, eels can serve as indicator, umbrella and flagship species, making them a comprehensive surrogate for the conservation of freshwater biodiversity.

Further Developments

This study confirmed the possibility that eels could be used as a surrogate species by using Japanese rivers as a model. These results could be applied to regions where, like in Japan, migratory species dominate freshwater ecosystems, such as islands that are relatively new geologically. On the other hand, continental freshwater ecosystems, for example, have a higher diversity of primary freshwater species that spend their entire lives in freshwater compared to Japan, therefore it is predicted that the impact of river-ocean connectivity on biodiversity would be lower than in the results of this study. However, trans-river structures also inhibit the mobility of primary freshwater species, such as upriver migrations for egg laying.

Sixteen species of eel have been discovered so far and they are globally distributed. Consequently, eels have the potential to be a surrogate species for freshwater biodiversity conservation worldwide, due to their importance in ecosystems as widely distributed higher-order predators, in addition to their commercial and cultural importance. It is hoped that further research could investigate this possibility in continental rivers and elsewhere.

Researchers led by King's College London announced today the first published results from PREDICT, the largest ongoing nutritional study of its kind.

The results, published in Nature Medicine and presented at the American Society of Nutrition 2020, showed a wide range of metabolic responses after eating in apparently healthy adults, and that inflammation triggered by the food we eat varies up to ten-fold.

Poor metabolic responses to food, where the body takes longer and works harder to clear the blood of fat and sugar, are linked with increased risk of conditions such as low-grade inflammatory diseases including heart disease, type 2 diabetes and obesity.

The results suggest improved health could be achieved by eating foods that are personalised to reduce inflammation after meals.

Senior researcher on the study Professor Tim Spector, King's College London, said:

"When it comes to weight, we've traditionally put a huge emphasis on factors we have no control over, like genetics. The fact is, while genetics plays a role, there are many more important factors that impact an individual's response to food and maintenance of a healthy metabolism. This study shows that achieving a healthy weight requires a scientific approach to eating that takes into account an individual's unique biology."

Led by Professor Tim Spector and his team at King's College London and spin-out health science company ZOE, in collaboration with researchers across the world, the PREDICT-1 study recruited participants across the UK and the US. This consisted of 1,103 participants, including 660 identical and non-identical twins from the TwinsUK cohort.

The study measured a wide range of markers from blood glucose, fat and insulin levels to exercise, sleep and gut bacteria (microbiome) over two weeks. It is the most detailed study to date to look at all the different factors that affect our responses to food together.

Despite wide variation in metabolic responses between participants, results from identical meals eaten on different days showed that individual responses to the same foods were remarkably consistent for each person.

PREDICT-1 study results showed:

A wide range of factors from gut microbes, blood sugar, fat and insulin levels to exercise and sleep impact an individual's ability to achieve optimal health.

Genetics plays a minor role in determining personal nutritional response and even identical twins can respond very differently to the same foods.

Everyone is unique in the way they respond to eating food (nutritional response), so there is no one "right" way to eat.

The optimal time to eat for nutritional health also depends on the individual rather than fixed "perfect" mealtimes. The researchers found that some people clearly metabolised food better at breakfast while others saw no difference.

Optimal meal composition in terms of fat, carbohydrates, proteins and fibre (macronutrients) is also highly individual, so prescriptive diets based on fixed macronutrient ratios are too simplistic and will not work for everyone. For example, a sensitive glucose responder may need to reduce carbohydrates whereas someone else may be able to eat these freely.

The proportions of nutrients explain less than 25% of our responses to food, showing the importance of how we eat (time of day, sleep, exercise etc.) as well as what we eat.

Dr Sarah Berry, Senior Lecturer of Nutrition Sciences at King's College London and first author of the Nature Medicine paper and the inflammation study presented at the American Society of Nutrition 2020 conference, said:

"We found that the increase in fat and glucose in our blood after eating a meal initiates an inflammatory response which differs hugely between individuals. Dietary and lifestyle strategies to reduce prolonged elevations in blood fat and glucose may therefore be a useful target to reduce low grade inflammation, and help prevent people from developing low-grade inflammatory conditions such as type 2 diabetes and cardiovascular disease."

Monash researchers are part of an international collaboration applying 'twistronics' concepts (the science of layering and twisting 2D materials to control their electrical properties) to manipulate the flow of light in extreme ways.

The findings, published today in the journal Nature, hold the promise for leapfrog advances in a variety of light-driven technologies, including nano-imaging devices; high-speed, low-energy optical computers; and biosensors.

This is the first application of Moire physics and twistronics to the light-based technologies, photonics and polaritonics, opening unique opportunities for extreme photonic dispersion engineering and robust control of polaritons on 2D materials.

APPLYING TWISTRONICS TO PHOTONS

The team took inspiration from the recent discovery of superconductivity in a pair of stacked graphene layers that were rotated to the 'magic twist angle' of 1.1 degrees.

In this stacked, misaligned configuration, electrons flow with no resistance, while separately, each of the two graphene layers shows no special electrical properties.

The discovery has shown how the careful control of rotational symmetries can unveil unexpected material responses.

The research team was led by Andrea Alù at the Advanced Science Research Center at the Graduate Center, CUNY, Cheng-Wei Qiu at National University of Singapore and Qiaoliang Bao formerly at Monash University.

The team discovered that an analogous principle can be applied to manipulate light in highly unusual ways. At a specific rotation angle between two ultrathin layers of molybdenum-trioxide, the researchers were able to prevent optical diffraction and enable robust light propagation in a tightly focused beam at desired wavelengths.

Typically, light radiated from a small emitter placed over a flat surface expands away in circles very much like the waves excited by a stone that falls into a pond. In their experiments, the researchers stacked two thin sheets of molybdenum-trioxide and rotated one of the layers with respect to the other. When the materials were excited by a tiny optical emitter, they observed widely controllable light waves over the surface as the rotation angle was varied. In particular, they showed that at the photonic 'magical twist angle' the configured bilayer supports robust, diffraction-free light propagation in tightly focused channel beams over a wide range of wavelengths.

"While photons - the quanta of light - have very different physical properties than electrons, we have been intrigued by the emerging discovery of twistronics, and have been wondering if twisted two-dimensional materials may also provide unusual transport properties for light, to benefit photon-based technologies," said Andrea Alù.

"To unveil this phenomenon, we used thin layers of molybdenum trioxide. By stacking two of such layers on top of each other and controlling their relative rotation, we have observed dramatic control of the light guiding properties. At the photonic magic angle, light does not diffract, and it propagates very confined along straight lines. This is an ideal feature for nanoscience and photonic technologies."

"Our experiments were far beyond our expectations," said Dr Qingdong Ou, who led the experimental component of the study at Monash University. "By stacking 'with a twist' two thin slabs of a natural 2D material, we can manipulate infrared light propagation, most intriguingly, in a highly collimated style."

"Our study shows that twistronics for photons can open truly exciting opportunities for light-based technologies, and we are excited to continue exploring these opportunities," said National University of Singapore graduate student Guangwei Hu, who led the theoretical component.

"Following our previous discovery published in Nature in 2018, we found that biaxial van der Waals semiconductors like α-MoO3 and V2O5 represent an emerging family of material supporting exotic polaritonic behaviors," said A/Prof Qiaoliang Bao, "These natural-born hyperbolic materials offer an unprecedented platform for controlling the flow of energy at the nanoscale."

DEVELOPMENT OF TWISTRONICS AND MAGIC ANGLES IN GRAPHENE

Novel electronic properties in 'misaligned' graphene sheets was first predicted by National University of Singapore Professor (and FLEET Partner Investigator) Antonio Castro Neto in 2007, and the 'magic angle' of 1.1 degrees was theorised by FLEET PI (University of Texas in Austin) in 2011.

Superconductivity in twisted graphene was experimentally demonstrated by Pablo Jarillo-Herrero (MIT) in 2018.

THE STUDY

Topological polaritons and photonic magic angles in twisted α-MoO3 bi-layers was published in Nature today, 11 June 2020 (DOI 10.1038/s41586-020-2359-9 ).

As well as support from the Australian Research Council, support was also provided by the US Air Force Office of Scientific Research, >Vannevar Bush Fellowship, Office of Naval Research, and National Science Foundation, as well as Singapore's Agency for Science Technology and Research (A*STAR), and China's National Natural Science Foundation.

Layering and twisting of 2D materials was performed at Monash University (Department of Materials Science and Engineering), while the topological polaritons was observed and characterised at the Melbourne Centre for Nanofabrication (MCN), the Victorian Node of the Australian National Fabrication Facility (ANFF).

PHOTONICS AT FLEET

Experimental physicist Dr Qingdong Ou is a research fellow now working with Prof Michael Fuhrer at Monash University to study nano-device fabrication based on 2D materials, within FLEET's Enabling technology B.

Qingdong seeks to minimise energy losses in light-matter interactions, aiming to realise ultra-low energy consumption in 2D-material-based photonic and optoelectronic devices. He also studies highly-confined low-loss polaritons in 2D materials using near-field optical nano-imaging within FLEET's Research theme 2.

FLEET is an Australian Research Council Centre of Excellence developing a new generation of ultra-low energy electronics.