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HERSHEY, Pa. -- The absence of a protein that works to prevent tumor formation may explain why some patients are resistant to a common cancer therapy, according to Penn State College of Medicine researchers. They said that testing cancers for the presence of this protein may help clinicians identify patients who may be resistant to or relapse when treated with the therapy.

Epidermal growth factor receptor (EGFR) is a protein that plays a role in cell division and survival signaling and is active in skin, bladder, esophageal, lung, liver, pancreatic, colon, and head and neck cancers. Patients with high amounts of this protein in their tumors tend to have a poor prognosis. EGFR-targeting therapies are used in clinical practice and are often initially effective in many patients. However, some patients are resistant to the therapy and many who were initially responsive to treatment relapse within a year.

Douglas Stairs, assistant professor of pathology and laboratory medicine and pharmacology, investigated why these patients may be resistant to EGFR therapies. He said mutations in the gene that contains the instructions for building EGFR or other genetic and cellular factors account for about 70% of resistance causes.

"There are still some reasons for resistance that are alluding scientists," said Stairs, a Penn State Cancer Institute researcher. "Our previous work showed that too much EGFR and reduced amounts of a protein called p120 catenin (p120ctn) can cause cancer to develop. We hypothesized that reduced amounts of p120ctn might also cause resistance to EGFR therapies."

In healthy cells, p120ctn strengthens cell-to-cell contact by cooperating with other proteins to strengthen connections between epithelial cells, which serve as the barrier between the body's external and internal surfaces. According to Stairs, scientists know that the cancer cells often have reduced amounts of p120ctn, but are unsure why.

To test their hypothesis, Stairs and colleagues cultured genetically-engineered esophageal cancer cells -- one set with normal amounts of EGFR and p120ctn, one set with higher amounts of EGFR, one set with lower amounts of p120ctn and another set with high amounts of EGFR and low amounts of p120ctn. They then treated each cell line with a series of EGFR-targeting therapies.

Cells with high amounts of EGFR died when treated with the therapies, while those with normal amounts of EGFR were not affected by the therapies. The cell lines that had high amounts of EGFR and reduced amounts of p120ctn were resistant -- demonstrating that loss of p120ctn is a critical component to the cells' resistance to EGFR-targeted therapies. The results were published in PLOS ONE.

Stairs said that while these results are promising, his lab will continue to explore the role of p120ctn loss in EGFR therapy resistance by testing the effect in cancer cells sampled from patients with colon, lung, oral or other cancers. They will also explore whether the cells with increased EGFR and decreased p120ctn are resistant to other EGFR therapies approved by the U.S. Food and Drug Administration.

"We also need to investigate further how the loss of p120ctn causes this resistance," Stairs said. "For now, we know that if patients who have high levels of EGFR in their samples were also tested for their levels of p120ctn, it may provide a clue to clinicians as to which patients are at risk for resistance to EGFR-targeting therapies or relapse."

While parents from diverse backgrounds most often value parks that offer amenities like playgrounds, sports fields and green spaces, they also want parks to feel safe, according to a survey by North Carolina State University researchers.

Published in the Journal of Healthy Eating and Active Living, the study findings were drawn from a survey of 278 parents with children aged 5 to 10 who visited parks in North Carolina's Triangle region and in New York City in the spring and summer of 2017 and 2018. The study was designed to pinpoint the most attractive park features for parents of different races and ethnicities in low-income communities. While researchers found several key differences by race and ethnicity in New York City, they did not see significant differences by race or ethnicity in the Triangle.

"Although there is no one-size-fits-all approach to encourage park use, our findings suggest emphasizing facilities and park safety are ways local government agencies could design and maintain parks that are attractive to parents and their children," said Scott Ogletree, the study's lead author and a postdoctoral researcher at NC State. "We were trying to get at what might encourage or discourage parents from bringing their children to parks, with the idea that's where kids can get physical activity through play."

Finding there were no significant differences by race in the Triangle indicated that many parents may share similar values for what they want in parks, Ogletree said. Across all parents in the Triangle, they saw that safety and safe facilities were most often cited, followed closely by physical features like playground equipment, sports fields and green areas.

When they broke down the findings for parents in New York City by race and ethnicity, one of the findings they considered most surprising was the low reported desire for increased safety and cleanliness in parks by parents who self-identified as Asian. They also found only three of 70 parents who self-identified as Asian reported an increased need for social amenities, such as activities within parks or more children to play with.

"This is not at all to say these are not desired attributes of parks and park programming by Asian families, but more likely suggests in the parks we surveyed that families felt safe, that there were other children to play with, and there was plenty to do," said J. Aaron Hipp, the study's senior author and an associate professor of community health and sustainability at NC State. "In turn, this result may point to shortcomings in safety, numbers, and activities in parks located in low-resourced and primarily Latinx and Black neighborhoods."

Parents who identified as Latinx in New York City highly valued the safety and security of the park, along with proximity and limited entrances. Latinx parents were also more likely to indicate the social environment of a park was important to them.

"In New York, where Latinx parents reported park safety was an important concern, we see a need to increase the sense of security in and around parks, such as ensuring adequate lighting, reducing incivilities such as litter or graffiti, or providing staff and community engagement opportunities," Hipp said.

Using the findings, researchers hope to help inform park developers so they can better serve diverse audiences.

"These findings can help point out aspects of parks that can be improved to meet the needs and desires of parents from diverse backgrounds," said study co-author Jing-Huei Huang, a Ph.D. candidate in parks, recreation and tourism management at NC State. "Making parks attractive can have beneficial outcomes from greater use of parks by children and adults."

In future work, they plan to explore the social, cultural, and environmental factors underlying differences they saw, and their role in park-use decisions.

"This work was one time point and only in 12 parks across the two regions," Hipp said. "Interviews and focus groups with parents and kids could help us better understand concerns and desires around safety, social interactions and activities."

New Rochelle, NY, December 21, 2020--Myanmar youth rely heavily on Facebook for news and information. This can be a platform for disseminating fake news and hate speech. With poor digital literacy skills, these youths may be susceptible to disinformation campaigns and other online dangers, according to the peer-reviewed journal Cyberpsychology, Behavior, and Social Networking. Click here (http://doi.org/10.1089/cyber.2020.0131) to read the article now.

Facebook and its sister app Messenger were used by 87.4% and 71.4% of Myanmar youth living in conflict-affected areas. Overall, 58% of respondents indicated that they use social media, mainly Facebook, to read news.

The results "suggest that young people living in conflict-affected areas of Myanmar are aware of the proliferation of fake news on social media, and often check the accuracy of the news they receive from this medium," states Dr. Brad Ridout, The University of Sydney, and coauthors. "However, the overreliance on Facebook for checking news accuracy, combined with poor literacy skills and low levels of trust in traditional and state-run media, may have a negative impact on the information ecosystem within which young people in Myanmar exist."

"Teaching young people media and information literacy has always been an important tool, to give them the critical thinking skills to properly navigate the information they are exposed to in everyday life. Digital networks that have enabled trans-border and trans-media information availability makes this education more important now than ever before to encourage us all to call into question the information encountered online," says Editor-in-Chief Brenda K. Wiederhold, PhD, MBA, BCB, BCN, Interactive Media Institute, San Diego, California and Virtual Reality Medical Institute, Brusse (https://home.liebertpub.com/publications/cyberpsychology-behavior-and-social-networking/10) is an authoritative peer-reviewed journal published monthly online with Open Access options and in print that explores the psychological and social issues surrounding the Internet and interactive technologies. Complete tables of contents and a sample issue may be viewed on the Cyberpsychology, Behavior, and Social Networking (https://home.liebertpub.com/publications/cyberpsychology-behavior-and-social-networking/10)
website.

Below please find a summary and link(s) of new coronavirus-related content published today in Annals of Internal Medicine. The summary below is not intended to substitute for the full article as a source of information. A collection of coronavirus-related content is free to the public at http://go.annals.org/coronavirus.

1. Modeling Study Suggests That Mitigation Efforts Can Prevent Most COVID-19 Cases on College Campuses

A modeling study from Brigham and Women's Hospital, Massachusetts General Hospital and Case Western Reserve University suggests that mitigation efforts can prevent most COVID-19 cases on college campuses. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-6558.

Researchers used the Clinical and Economic Analysis of COVID-19 interventions (CEACOV) model to analyze mitigation strategies. They evaluated 24 mitigation strategies based on four approaches: social distancing, mask-wearing policies, isolation, and laboratory testing. The team compared results from a minimal social distancing program, in which only large gatherings such as sporting events or concerts were canceled, and an extensive social distancing program, where all large classes and 50 percent of smaller classes were delivered online. Laboratory testing ranged from no testing of asymptomatic students and faculty to routine testing at 14-, 7-, or 3-day intervals. Based on the model, combining a mandatory mask-wearing policy with extensive social distancing would prevent 87 percent of infections among students and faculty. Routine testing was also found to be highly effective at preventing infections in the model but may be cost-prohibitive for many colleges and universities.

The researchers caution that even if campuses remain closed, there would likely be infections among faculty acquired from the surrounding community, as well as infections among students who return to live off-campus in and around college towns.

Media contacts: A PDF for this article is not yet available. Please click the link to read full text. The lead corresponding author, Elena Losina, PhD, can be reached through Eliza Powell at epowell5@bwh.harvard.edu.

2. Patient-physician race concordance may modestly increase COVID-19 knowledge and information seeking

The paucity of public health messages that directly address communities of color might contribute to racial and ethnic disparities in knowledge and behavior related to coronavirus disease 2019 (COVID-19). Physicians have increasingly reached out to the community on social media. Whether or not these messages matter, and whether or not physician race/ethnicity affects information uptake is not clear. Read the full text: https://www.acpjournals.org/doi/10.7326/M20-6141.

Researchers from MIT Department of Economics, Massachusetts General Hospital, and other top academic institutions, randomly assigned 14,267 self-identified Black or Latinx adults to either first view three video messages regarding COVID-19, delivered by physicians, that varied by physician race/ethnicity, acknowledgment of racism/inequality, and community perceptions of mask-wearing and then answer questions, or answer questions first and then watch the videos. The goal was to determine whether physician-delivered prevention messages affect knowledge and information-seeking behavior of Black and Latinx individuals and whether this differs according to the race/ethnicity of the physician and tailored content. The researchers found a small but statistically significant increase in COVID-19 knowledge when viewing the video first that did not differ by race concordance between the physician messenger and the viewer. However, information seeking (click through on links that offered further information on COVID-19) was higher among African American participants after they viewed messages from African American physicians.

The authors of an accompanying editorial from Johns Hopkins Center for Health Equity suggest that this study provides insight during a critical time. As new vaccines against COVID-19 become available, and when so many lives are at stake, mistrust of institutions and science remains high. This mistrust is especially high in U.S. communities of color, which have borne the greatest burden during the pandemic. They suggest further study focusing on whether COVID-19 information seeking is a predictor of actual behavior change. Read the full text here: https://www.acpjournals.org/doi/10.7326/M20-8057.

Media contacts: A PDF for this article is not yet available. Please click the link to read full text. The lead corresponding author, Esther Duflo, PhD, can be reached through Peter Dizikes at dizikes@mit.edu. Click here for more information from the authors.

3. ACP, Annals of Internal Medicine host virtual COVID-19 Vaccine Forum II for physicians

Panel offers timely, evidence-based advice for promoting vaccine confidence and uptake

As COVID-19 vaccines are becoming available, physicians and other health care professionals must do the hard work of making sure sufficient numbers of people are vaccinated to end the pandemic. To help prepare them, the American College of Physicians (ACP) and Annals of Internal Medicine hosted the COVID-19 Vaccine Forum II - Promoting COVID-19 Vaccination on Dec. 16 where a panel of infectious disease experts discussed strategies for gaining public trust and acceptance of the vaccine. This was the second in a series of vaccine forums hosted by ACP and Annals of Internal Medicine.

ACP and Annals of Internal Medicine invited four experts to offer their perspectives on the vaccine and the current barriers to optimal uptake. Panelists included Dr. Ada Adimora from University of North Carolina, Dr. Helen Gayle from the Chicago Community Trust, Dr. Peter Hotez from Baylor University, and Dr. Heidi Larson from the London School of Tropical Medicine. Dr. Ryan Mire, a member of ACP's Board of Regents and a practicing internist in Nashville, and Dr. William Schaffner from Vanderbilt University moderated the discussion. The full recording is available for replay here and is published in Annals of Internal Medicine along with commentary by Christine Laine, MD, MPH, ACP senior vice president and editor-in-chief, Annals of Internal Medicine; Deborah Cotton, MD, MPH, deputy editor, Annals of Internal Medicine, and Darilyn V. Moyer, MD, Executive Vice President, and CEO, ACP.

During the forum, the panelists discussed the current vaccines, when and how they might be disseminated to patients, bearing fairness and equity in mind, and the challenges ahead related to influencing public opinion about the safety of the vaccine. Panelists stressed the need to build trust among disproportionally affected minority communities to ensure adequate uptake of the COVID-19 vaccines. Every member of the panel agreed that a comprehensive public health communications campaign would be needed to promote the vaccine and refute the glut of misinformation that has been circulating online.

Media contacts: A PDF for this article is not yet available. Please click the link to read full text. To speak with someone from ACP, please contact Andrew Hachadorian at AHachadorian@acponline.org.

An international team of researchers from the Chinese Academy of Sciences, Zhejiang A & F University and the University of Eastern Finland have found that regardless of whether flowering or leaf unfolding occurred first in a species, the first event advanced more than the second over the last seven decades.

In the four European tree species the researchers looked at: horse chestnut, scots pine, alder and ash, the time interval between leaf unfolding and flowering increased at a rate of 0.6 to 1.3 days per decade between 1950 - 2013. Similar trends were seen geographically, with the time interval between the two life-cycle (phenological) events being greater in trees in warmer areas of Europe.

Although leaf unfolding and flowering have both been shown to be happening earlier with climate warming, this is the first large scale study to examine both phenological events together and show that they are not advancing at the same rate in response to climate warming.

Leaf unfolding and flowering are key annual events for trees with each signalling the start of growth and reproduction, respectively. The timing of these events is crucial for maximising fitness.

"The unequal advances of leaf unfolding and flowering may alter trees' partitioning of resources between growth and reproduction and could leave flowers or leaves vulnerable to late spring frost damage if they appear too early" said Dr Jian-Guo Huang, the corresponding author of the study. "This could have impacts on tree species health and further affect ecosystem structure and function."

Species that produce flowers before leaves, like ash, could suffer losses in seed production if flowers were damaged by late spring frost. For species that produce leaves before flowers, like horse chestnut, late spring frost damage to leaves could reduce growth and carbon uptake.

Dr Qianqian Ma, lead author of the study said "The timing of phenological events is very sensitive to environmental factors, with temperature being particularly important in temperate plants. The changes in phenology we observed in our study may affect both growth and reproductive development in tree species and ultimately affect the ecosystem, nutrient cycles and carbon storage."

Tree species have evolved an optimal timing for growth and reproduction based on historic climate conditions. Changes to flowering times could disrupt interactions with pollinators, impacting the survival of both species with knock-on consequences for the ecosystem. Changes to when trees are able to grow in the year can have further consequences to their survival and carbon uptake.

The triggering of these phenological events is closely linked to temperature changes in the seasons. "Plants often require an exposure to chilling temperatures during winter as a cue for rest before the bursting of leaf buds or flowering can be triggered by a sufficient exposure to warmer temperatures in spring." explained Dr Qianqian Ma.

For each tree species, leaf unfolding and flowering have evolved to occur in a predetermined order. Although leaf unfolding occurs first in most species, those pollinated by wind, like alder and ash, flower first so that leaves don't inhibit pollen dispersal.

To collect the data on the four tree species, the researchers used the Pan European Phenology (PEP) network. This database contains annul observations of the date when leaves first unfold (or separate for evergreens) and the date when flowers first emerge for tree species across Europe. With this data the authors calculated the time intervals between first leaf date and first flower date between 1950 - 2013 and assessed this with corresponding temperature data.

Dr Qianqian Ma said: "Using long-term phenological records in Europe, we examined simultaneously the responses of both leaf unfolding and flowering of four common temperate tree species: ash, alder, horse chestnut and scots pine to climate warming."

These trees were chosen to give a mix of deciduous and evergreen trees with different orders of leaf unfolding and flowering.

Ideally more species would have been included in the study, but the researchers could only look at tree species with data on first leaf, first flower date and temperature. Only four tree species had sufficient data records over long enough time periods and large enough geographic areas.

Dr Jian-Guo Huang said: "Further studies that simultaneously monitor the timing of phenological events and the allocation of resources within plants are needed to better evaluate the consequences of altered phenology under climate warming."

Prof. PAN Jianwei and his colleges from University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) have achieved the experimental verification of distribution quantum phase estimation for the first time. This work was published on Nature Photonics.

Distributed metrology is a key tool to measure several locations from remote simultaneously with high precision, one typical task of which is the monitoring of stress field and temperature field of bridge and airplane.

In line with the development of quantum technology, metrology also entered quantum era. When targeting on the measurement of multiple parameters distributed in space, distributed quantum metrology can enhance the sensitivity of measurements beyond the classical limits.

However, the researchers are wondering how to achieve entangled states for optimal precision of multiparameter measurement, which was known as the ultimate Heisenberg limit.

In this study, Prof. PAN's team designed the optimal measurement scheme using entangled photons, and demonstrated measurement of individual phase shifts and their average. The precision went beyond the theory limit of classical sensor.

By considering both photon entanglement and coherence, Prof. PAN's team further demonstrated linear combination of multiple phase shifts with the total number of parameters to measure up to 21. This combined scheme both enlarged the number of measurable parameters and enhanced the precision compared with using photon entanglement only.

This study assesses the precision of measurement in different entanglement strategies and provided the verification of the benefit of entanglement and coherence for distributed quantum metrology. It lays a foundation for future application of high-precision distributed quantum metrology.

Other than a spicy night snack, the crayfish has been endowed with greater significance. Prof. ZHU Xifeng's team from University of Science and Technology of China (USTC) of the Chinese Academy of Sciences (CAS) made it possible to use crayfish shell as the biological template for high-performance supercapacitors. This work was published in Carbon.

Compared with other high-performance materials, biomass has long been regarded as a promising one for its environmental-friendliness and extensive resources. However, practical application of biomass is restricted by their relatively rare efficient storage sites, low diffusion kinetics and the need for huge amount of premade nano templates.

To solve the problems, the researchers innovatively introduced crayfish shells to get the biological template.

Shells were dried, ground and pretreated in an alkaline solution to retrieve templates, which were then mixed with the heavy fraction of bio-oil derived from agricultural waste to manufacture hierarchical porous carbons, a kind of supercapacitor material.

The mixed product delivered magnificent capacitance of 351 F/g thanks to its ultrahigh specific surface area, large total pore volume and reasonable content of oxygen atoms, which are of importance to a capacitor.

Besides, the symmetric supercapacitors assembled by the synthetic samples showed a superior energy density of 20 Wh/kg at a power density of 350W/kg, preceding other biomass materials.

This method possesses an environmental friendly solution for the power storage problem of the rapid-growing wearable displays, electric vehicles and smartphones.

An infant's odd case of rare encephalitis not typically found in children led researchers to discover never before seen genetic mutations and a more accurate technique to examine the IRAK4 gene responsible for innate immunity.

The IRAK4 gene instructs the production of a protein that plays a key role in the early recognition and response to invading pathogens. Inherited mutations in this gene can cause an immune system disorder that leaves the body susceptible to recurrent infections of pus-forming pyogenic bacteria. Cases of IRAK4 deficiency are quite rare and only about 10 familial instances were identified so far in Japan.

A Hiroshima University-led research team detected two novel IRAK4 mutations, c.29_30delAT (p.Y10Cfs*9) and c.35G>C (p.R12P), in a 10-month-old boy with anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis and human herpesvirus 6 (HHV6) reactivation. The p.Y10Cfs*9 and p.R12P variations were inherited from his father and mother, respectively. The research team found the mutations by using whole exome sequencing (WES), a method used to exhaustively examine the DNA for genetic disorders.

Anti-NMDAR encephalitis, an inflammation of the brain, happens when the immune system attacks a vital brain receptor, causing psychiatric symptoms, involuntary movement, seizures, autonomic dysfunction, and central hypoventilation. It typically occurs in adult females suffering from ovarian tumor. Only a few cases of anti-NMDAR encephalitis have been so far reported in infants.

The researchers suspect that reactivation of HHV6 may have induced brain damage that triggered the production of anti-NMDAR antibodies.

"It is well known that anti-NMDAR encephalitis is triggered by HSV1 (herpes simplex virus) infection. The post-infectious autoimmune process that follows the HSV-induced brain damage is thought to be the cause of anti-NMDAR encephalitis," the researchers said in their study published in the Journal of Clinical Immunology.

"The coexistence of anti-NMDAR encephalitis and HHV6 reactivation in this patient may reveal an unknown manifestation associated with IRAK4 deficiency," they said.

More precise method to analyze IRAK4 mutations

Although the researchers have yet to find direct evidence demonstrating a relationship between IRAK4 deficiency and the development of anti-NMDAR encephalitis or HHV6 reactivation, they were able to establish that mutations p.Y10Cfs*9 and p.R12P are damaging.

The researchers developed a novel NF-κB reporter assay that can precisely evaluate whether an IRAK4 mutation is harmful. The reporter assay allows them to investigate the activation of transcription factor NF-κB which regulates the body's inflammatory responses.

"Using this system, we confirmed that both novel mutations are deleterious. The current case revealed the possibility that genetics can contribute to characterizing infantile cases with anti-NMDAR encephalitis," study author Satoshi Okada, a professor at HU's Graduate School of Biomedical and Health Sciences, said.

They resolved potential issues of misevaluation in a previously developed NF-κB reporter assay by using CRISPR gene-editing technology to remove the IRAK4 naturally expressed in the HEK293 cell -- commonly used in studying gene function as it is much easier to transfect than other cell lines.

"HEK293 cells have endogenous IRAK4 expression. Their endogenous IRAK4 prevents the precise evaluation of the activity of introduced WT or mutant IRAK4," Okada explained.

To date, there are so far 24 known mutations identified in patients with IRAK4 deficiency.

The research team hopes to soon introduce their novel NF-κB reporter assay system to help evaluate IRAK4 gene mutations and achieve early diagnosis.

Waveguides and resonators are core components in electronics, photonics, and phononics, both in existing and future scenarios. In certain situations (space or frequency), critical coupling can occur between the two components, i.e., no energy passes through the waveguide after the incoming wave is coupled into the resonator. The transmission spectral characteristics resulting from this phenomenon are highly advantageous for signal filtering, switching, multiplexing, sensing, etc. However, under the existing mechanism, the occurrence of critical couplings always leads to increased reflection in the input channel due to the inevitable backscattering in practical. These reflection will further induce both intra- and interchannel crosstalk (noise) in an integrated system, whose accumulation will tend to generate large performance degradations, or even result in rapid failure of system functions. Unlike the electronic system, a passive integrated photonic or phononic diode has not been put into practical use thus far, although massive notable attempts have been made. Therefore, avoiding input reflections, especially in spectral functional devices, poses a challenge for further development of integrated photonic or phononic circuitry.

Recently, Yu and his colleagues at Nanjing University have designed a brand-new waveguide-resonator by using the principle of topological insulator (TI), which solves the above "input reflection" problem fundamentally. As a major achievement in condensed matter physics since this century, TI materials are promising to create future high-performance electronics and computers, since electrons with spin ±½ at the TI boundaries are lossless one-way conducting as they are moving on a superhighway. By constructing artificial spin ±½, photonic and phononic TIs also have been proposed and created in recent years, offering revolutionarily waveguides for photons and phonons with spin-direction locking at the TI boundaries. Photon/phonons transports on these waveguides are backscattering-free to defects such as fabrication imperfections or arbitrary bends, without any losses induced to their transmission energy.

Following these ideal waveguides, a thought-provoking application-driven question is whether spectral functions can be implemented inside them. Specifically, it is asked whether there is a resonator solution that matches these TI waveguides. An effective way is to wrap the TI waveguides themselves into closed loops, creating TI ring-resonators like whispering galleries in many acoustic and optical scenarios. The research at Nanjing University found that, unlike conventional ring resonators, a TI ring-resonator unavoidably supports two kinds of modes simultaneously, i.e., travelling-wave whispering-gallery modes (WGMs) and split standing wave modes (SWMs). In the TI resonator, these two kinds of modes support different spin quantum numbers (±½ and 0), respectively, thus need to meet different conditions for critical coupling to the TI waveguide.

When a TI-SWM resonator is coupled to a TI waveguide, because the spin-less SWM (spin 0) can be converted with both forward (with spin +½) and backward (with spin -½) modes in the TI waveguide, even if the initial state of the whole system has only one arbitrary spin (+½, 0, or -½), eventually, all three spins (+½, 0, and -½) can be excited. Consequently, there is always input reflection when critical coupling occurs, similar to conventional scenarios. Advantageously, when a TI-WGM resonator is coupled to a TI waveguide, because both of them support the same spins ±½ locked with wave direction, if the initial state of the system has only one spin, then back reflections with the opposite spin are unable to be excited, even in the case of critical coupling. The latter critical coupling is of particular favorable because when it meets: 1) reflections and induced noise are completely eliminated while the required transmission spectral characteristics are retained and 2) the incident energy is bound entirely inside the resonator with no channel through which to exit, resulting in an extremely high energy capacity/density. All these advantages make the TI waveguide-resonator exceed the performance of all conventional designs.

This research provides strong support for applying the principle of topological insulator to practical device performance and functionalities. It opens an avenue for integrated topological photonics and phononics for e.g., advanced signal processing, sensing, lasering, in both classical and quantum regions.

Older adults about to undergo elective surgery should undertake a sustained programme of targeted exercise beforehand to counteract the muscle-wasting effects of bedrest, new research suggests.

A study published by researchers in the University of Birmingham's School of Sport, Exercise and Rehabilitation Sciences showed that short term 'prehabilitation' strength exercises, undertaken pre-surgery, are insufficient to prevent muscle loss.

In the study, the researchers asked a group of older adults to perform four sessions of weight lifting exercise over one week. The participants did the exercises using only one leg, while the other leg did no exercise at all.

After completing the prehabilitation, the participants underwent five days of bed-rest - a typical length of stay in hospital for an older patient. Although the researchers expected to find that the leg which had undergone the exercise would experience less muscle loss than the other leg, in fact they found muscle loss was about the same in both legs.

The team's detailed analysis showed that, while short-term exercise prehabilitation does enhance the body's muscle-building processes, thigh muscle-wasting was about 3-4 per cent in both legs - roughly equivalent to what older adults would typically lose over 3-5 years of ageing.

The researchers recommend that one approach to protect older muscle from wasting during hospitalisation is to perform longer-term strength exercise prehabilitation beforehand.

Dr Leigh Breen, the study's corresponding author, says: "Although short-term prehabilitation offers a cost-effective and easy-to-implement strategy, it does not prevent muscle wasting among older adults undergoing bed-rest. This muscle loss may be extremely hard to recover from and can lead to long-term health and disease complications."

The team recommend that prehabilitation exercise programmes should also incorporate aerobic exercise alongside strength training to protect cardiovascular health, and a protein rich diet to increase muscle mass levels in a way that will effectively cancel out the muscle loss that is experienced during bed-rest

They also recommend that, where appropriate and safe, hospitalised older patients should aim to get back on their feet and mobile again as quickly as possible. Post-surgery exercise and dietary strategies will also be important to ensure a return to full health and lower the risk of future health complications.

Dr Benoit Smeuninx, now at Monash University in Australia, is lead author on the paper. He says: "Our study reinforces the need for more research into the benefits of longer term training programmes prior to surgery. In the same was as an athlete would train before a race or a competition, exercise training before hospitalisation is likely to be highly beneficial to older adults undergoing elective surgeries."

The work was completed in collaboration with colleagues within the Medical Research Council Versus Arthritis Centre for Musculoskeletal Ageing Research, which is a partnership between the University of Birmingham and the University of Nottingham. The work was funded by the Biotechnology and Biological Sciences Research Council.

Synchronization and transients are two fundamental phenomena in nonlinear and complex dynamical systems, and they also emerge ubiquitously in ecology and evolutionary biology. Synchronization is commonly observed in spatially extended ecological systems and is regarded as the dynamical basis for the emergence of ecological cycles and orders, yet there is little understanding of the underlying mechanism. Likewise, transient dynamics are fundamental to the conservation and management of ecological systems, yet the analysis of transient dynamics in spatiotemporal ecological systems remains a challenge. The two phenomena, which have been studied separately in the past, are unified in a recent study by Huawei Fan and Xingang Wang from Shaanxi Normal University, Ling-Wei Kong and Ying-Cheng Lai from Arizona State University, and Alan Hastings from University of California Davis. The paper, entitled "Synchronization within synchronization: transients and intermittency in ecological networks" is published in the Beijing-based journal of National Science Review.

The class of systems studied is a ring-structure ecological network of patches, each with a chaotic predator-prey type of dynamics. Each oscillator describes the local population dynamics of a patch, in which there are three interacting species: vegetation, herbivores and predators. When isolated, the dynamics of the oscillators are chaotic. The oscillators are coupled with each other through the migrations of herbivores and predators. In the presence of couplings, all oscillators are synchronized in phase. The authors found that, enclosed within phase synchronization, complete synchronization in both phase and amplitude of the abundance oscillations can emerge among certain subsets of the patches.

The subsets of synchronized oscillators are determined by the intrinsic symmetries of the network, i.e., each symmetry generates a specific configuration of the subsets (or clusters of oscillators). There is then cluster synchronization. As complete synchronization among a subset of patches occurs under the umbrella of phase synchronization among all the patches, this phenomenon is named "synchronization within synchronization."

The striking feature of this phenomenon is that the synchronous dynamics associated with any configuration are transient: any cluster synchronization can be maintained for only a finite amount of time when the network is subject to intrinsic stochasticity due to chaos and/or random noise of arbitrarily small amplitude. When one form of cluster synchronization breaks down, a new form of cluster synchronization allowed by the system symmetry emerges. In the course of time evolution, there is intermittent switching among the distinct patterns of cluster synchronization. The duration of any cluster synchronization state, or the transient time, is found to obey an algebraic scaling law. Mathematically, the emergence of transient cluster synchronization, intermittency, and the distribution of the transient lifetime can be understood through a dynamical stability analysis based on symmetry considerations. The finding and analysis provide a quantitative, unified picture of transients and synchronization.

Ecologically, in addition to transients in patch synchronization dynamics, the finding implies that the ubiquitous phenomenon of population cycles can possess a more organized dynamical structure than previously thought: not only do the populations in all patches exhibit the same trend of variation as characterized by phase synchronization, but certain patches can also have the same population at any time even they are not directly coupled and are separated by a large distance. In fact, nearby patches, in spite of being directly coupled, may not be completely synchronized. The results establish the possibility and the dynamical mechanism for the occurrence of spatially "remote" synchronization in ecological systems.

For the field of ecology, the study reveals the fundamental role played by network symmetry in the emergence of dynamical patterns in spatiotemporal ecological systems, which can be potentially used to explain some intriguing, counterintuitive synchronization phenomena. For example, in a previous work on a class of dispersal ecological networks, it was found that randomizing the structure of an otherwise regular network tends to induce desynchronization with prolonged transient dynamics. This contrasts the result in the literature of complex networks where synchronization is typically favored by creating random shortcuts in a large regular network. The paradox is naturally resolved by resorting to symmetry considerations: adding random shortcuts destroys the network symmetries and, consequently, the corresponding synchronization patterns.

For the field of nonlinear dynamics and complex systems, the finding extends our knowledge on the synchronization behavior of coupled dynamical systems. Cluster synchronization and synchronization patterns are widely recognized as the dynamical basis for the functioning and operation of many realistic complex systems. An important feature of the patterns, as revealed by various empirical and experimental studies, is that they are non-stationary, i.e., with time the system can switch dynamically among different patterns. The current study reproduces successfully this non-stationary pattern and, more importantly, provides a general underlying mechanism: transient synchronization.

The finding provides insights into the management and conservation of ecological systems, and the theory developed and the mechanism uncovered can be generalized to broader complex dynamical systems for a deep understanding of the interplay among synchronization, transients, intermittency, and nonstationarity.

Scientists at The Marine Mammal Center in Sausalito, CA - the largest marine mammal hospital in the world - and international colleagues have identified a novel skin disease in dolphins that is linked to climate change. The study is a groundbreaking discovery, as it is the first time since the disease first appeared in 2005 that scientists have been able to link a cause to the condition that affects coastal dolphin communities worldwide. Due to the decreased water salinity brought upon by climate change, the dolphins develop patchy and raised skin lesions across their bodies - sometimes covering upwards of 70 percent of their skin.

The international study, which can be found here, was co-authored by three internationally respected scientists, from California and Australia:

Dr. Pádraig Duignan, Chief Pathologist at The Marine Mammal Center

Dr Nahiid Stephens, a veterinary pathologist at Murdoch University (Perth, Australia)

Dr. Kate Robb, Founding Director, zoologist, and geneticist of the Marine Mammal Foundation (Victoria, Australia)

The study, published in Scientific Reports, a peer-reviewed natural sciences journal, provides the first-ever case definition for fresh-water skin disease in bottlenose dolphins.

This study comes on the heels of significant outbreaks in Louisiana, Mississippi, Alabama, Florida and Texas and Australia in recent years. In all of these locations, a sudden and drastic decrease in salinity in the waters was the common factor. Coastal dolphins are accustomed to seasonal changes in salinity levels in their marine habitat, but they do not live in freshwater. The increasing severity and frequency of storm events like hurricanes and cyclones, particularly if they are preceded by drought conditions, are dumping unusual volumes of rain that turn coastal waters to freshwater. Freshwater conditions can persist for months, particularly after intense storms such as hurricanes Harvey and Katrina. With the increasing climate temperatures, climate scientists have predicted extreme storms like these will occur more frequently and, consequently, will result in more frequent and severe disease outbreaks in dolphins.

"This devastating skin disease has been killing dolphins since Hurricane Katrina, and we're pleased to finally define the problem," said Duignan. "With a record hurricane season in the Gulf of Mexico this year and more intense storm systems worldwide due to climate change, we can absolutely expect to see more of these devastating outbreaks killing dolphins."

The study has major implications for the current outbreak in Australia, which is impacting the rare and threatened Burrunan dolphin in southeast Australia, and could provide professionals with the information needed to diagnose and treat affected animals. Currently, the long-term outlook for dolphins affected with the skin disease is poor. This is especially true for the animals suffering from prolonged exposure to freshwater.

The deadly skin disease was first noted by researchers on approximately 40 bottlenose dolphins near New Orleans after Hurricane Katrina in 2005.

"As warming ocean temperatures impact marine mammals globally, the findings in this paper will allow better mitigation of the factors that lead disease outbreaks for coastal dolphin communities that are already under threat from habitat loss and degradation," said Duignan. "This study helps shed light on an ever-growing concern, and we hope it is the first step in mitigating the deadly disease and marshalling the ocean community to further fight climate change."

Leading a collaboration of institutions in the U.S. and abroad, the Princeton University Department of Chemistry is reporting new topological properties of the magnetic pyrite Cobalt disulfide (CoS2) that expand our understanding of electrical channels in this long-investigated material.

Using angle-resolved photoelectron spectroscopy and ab-initio calculations, researchers working with the Schoop Lab discovered the presence of Weyl nodes in bulk CoS2 that allow them to make predictions about its surface properties. The material hosts Weyl-fermions and Fermi-arc surface states within its band structure, which may enable it to serve as a platform for exotic phenomena and places it among materials candidates for use in spintronic devices.

The research also settles a long-standing debate, proving that CoS2 is not a true half-metal. A half-metal is any substance that acts as a conductor to electrons of one spin orientation but as an insulator or semiconductor to those of the opposite orientation. Although all half-metals are ferromagnetic, most ferromagnets are not half-metals. This finding that CoS2 is not a half-metal has important implications for materials and device engineering.

Leslie Schoop, assistant professor of chemistry at Princeton Chemistry, called the work "a rediscovery of new physics in an old material." The research was published this week in Science Advances.

CoS2 has been a subject of study for many decades because of its itinerant magnetism, and since the early 2000s - before topological insulators were predicted and discovered - because of its potential to be a half-metal. Researchers were "happy" to put the latter discussion to rest.

Through the Schoop research, the material was discovered to be a rare example of that group of magnetic topological metals proposed as agents of charge-to-spin conversion. By disentangling the bulk and surface electronic structure of CoS2, researchers have demonstrated that there is a relationship between electronic channels in the inner material that can predict other states at its surface. In a material, an electrical current can go through the bulk or flow along the surface. Researchers found that bulk CoS2 contains objects called Weyl nodes within its structure that serve as electronic channels that can predict other states at the surface.

"The beautiful physics here is you have these Weyl nodes that demand spin-polarized surface states. These may be harvested for spintronic applications," said Schoop.

"These electronic states that only exist at the surface have chirality associated with them, and because of that chirality the electrons can also only move in certain directions," she added. "Some people think about using these chiral states in other applications. There aren't many magnetic materials where these have been found before."

Chirality refers to that property that makes an object or system indistinguishable from its mirror image - i.e. not superimposable - and is an important property in many branches of science.

Schoop added that the electronic channels are polarized. This magnetism could potentially be used to manipulate the material: scientists can switch the magnetization direction and surface states could then be reconfigured as a response to this applied magnetic field.

Paper co-author Maia Vergniory, of the Donostia International Physics Center in Spain, added, "There are just a very few magnetic materials that have been measured to have such surface states, or Fermi arcs, and this is like the fourth, right? So, it's really amazing that we could actually measure and understand the spinchannels in a material that was known for so long."

As colleagues in 2016, Schoop and Vergniory discussed investigating the material properties of CoS2, particularly whether it could be classified as a true half-metal. The investigation went through several iterations after Schoop arrived at Princeton in 2017, and was worked on by graduate students under Schoop and under Vergniory at Donostia.

Niels Schröter, a colleague at the Paul Scherrer Institute in Switzerland and lead author on the paper, oversaw the team at the Swiss Light Source that mapped out the material Weyl nodes.

"What we wanted to measure was not just the surface electronic structure," said Schröter. "We also wanted to learn something about the bulk electronic properties, and in order to get both of these complementary pieces of information, we had to use the specialized ADRESS beamline at the Swiss Light Source to probe electrons deep in the bulk of the material."

Schröter explained how engineers might build a device down the road using this material.

"You would put this material in contact with another material, for instance with a magnetic insulator or something like that in which you then want to create magnetic waves by running an electric current through it.

"The beauty of these topological materials is that these interfacial electrons that may be used for spin-injection, they are very robust. You cannot easily get rid of them. This is where these fields of topology and spintronics may meet, because topology is maybe a way to ensure that you have these spin-polarized interface states in contact with other magnetic materials that you would like to control with currents or fields."

Schoop added, "I think that this kind of rediscovery in this very old and well-studied material is very exciting, and I'm glad I have these two amazing collaborators who helped nail it down."

A team of researchers, using satellite data and other analytical tools, has identified companies fishing in high seas--waters that lie outside of national jurisdiction where fishing has raised fears about environmental and labor violations. The study, which appears in the journal One Earth, is the first to link companies to fishing activity in these largely unregulated areas.

"There is a lot of concern about companies that operate on the high seas, simply because there they are beyond the reach of any nation's laws and regulations," says Jennifer Jacquet, an associate professor in NYU's Department of Environmental Studies and lead author of the peer-reviewed study. "By connecting those boats with specific companies, this study takes a first step in enhancing transparency--we now know a lot more about who is profiting from fish catches in the global commons."

The findings illuminate a significant element of commercial fishing. Previously, researchers could only identify which countries reported catching fish on the high seas, which account for 60 percent of the world's oceans and therefore represent a substantial proportion of waters that lie beyond the reach of national jurisdiction.

"We also have a much better sense of what we don't know," adds first author Gabrielle Carmine, a doctoral candidate at Duke University's Nicholas School of the Environment who worked with Jacquet as an NYU undergraduate. "The corporate actors we know vary by fishing gear type and by location in the high seas. For example, we know far more about the trawling fleet than the longline fleet and more about the Atlantic Ocean than the Western Tropical Pacific."

Species caught on the high seas are fished by industrial fleets and destined mainly for high-end markets in the U.S and Europe. Past assessments of high seas fish populations show that fishing in these waters has led to extraordinary declines in the abundance of many open-ocean species, including several species of tuna, swordfish, and marlin. While fish catches are reported by nations, many companies catch and profit from fish in the global ocean, where fishing is subject to few regulations because the high seas lie beyond national jurisdiction.

Combining data that detects fishing vessels made available from Global Fishing Watch with other public databases, such as regional fisheries management organizations and shareholder information, the team's analysis showed 1,120 corporations owned nearly 2,500 high seas fishing vessels in 2018--or approximately two-thirds of the total detected fishing effort in these waters.

However, high seas fishing is notably concentrated among a small number of entities. The Korean companies Sajo Group and Dongwon, which owns the U.S. subsidiary Starkist, were in the top 10 of the most active corporations on the high seas, along with a handful of Chinese corporations and one U.S. corporation based in Hawaii. Approximately 100 companies, based in the United States, the United Kingdom, China, Taiwan, Russia, Spain, the Netherlands, and South Korea, among other nations, accounted for more than one-third of high seas fishing during the studied period.

"These results provide a unique lens through which to view accountability for the use and protection of global ocean biodiversity," observes Jacquet.

Peroxisomes are essential, membrane-enclosed vesicles that occur in every cell. An arsenal of enzymes inside them breaks down harmful substances, thereby detoxifying the cells. A team of scientists led by Prof. Dr. Bettina Warscheid from the University of Freiburg, Prof. Dr. Ralf Erdmann from the Ruhr University Bochum and Prof. Dr. Christos Gatsogiannis from the University of Münster, formerly at the Max Planck Institute (MPI) of Molecular Physiology in Dortmund, has studied the molecular complex that carries the enzymes to where they are needed in the peroxisome. They have been able to cast light on the structure of the complex with great precision and obtain insights into the mechanisms of how it functions. Their results have been published in the journal Proceedings of the National Academy of Sciences of the United States of America (PNAS).

The cell contains numerous vesicles of different sizes. Known as 'organelles', they carry out specific functions. While mitochondria are like power stations providing energy for the cells, peroxisomes are more like sewage plants. Here, dozens of enzymes work on the degradation of harmful substances and the synthesis of useful ones. The toxic hydrogen peroxide produced during this process is immediately neutralized in the peroxisomes. Defects in peroxisomes or their enzymes lead to severe diseases, usually with fatal outcomes.

Like most organelles, peroxisomes also cannot produce their own enzymes. Instead, the right enzymes must be distributed to the right organelles. Enzymes intended for the peroxisome have one of two specific signal sequences that are recognized and bonded by import receptors in the interior of the cell. These import receptors are then passed from a docking complex to access pores in the peroxisomal membrane which trap the enzymes. Ralf Erdmann's group has already been able to show in earlier work that the enzymes are transported into the interior by different pores, depending on which of the two signal sequences they carry. "Until now we've known very few details about this process though," says Erdmann. The docking complex that traps the import receptors on the peroxisomal membrane appears to have a key role. Now the researchers have succeeded for the first time in determining the architecture of this complex at near-atomic resolution. "The close cooperation of scientists with expertise from different fields was the key to success," stresses Bettina Warscheid.

Essential components of the docking complex are the two proteins Pex14p and Pex17p. Tobias Hansen succeeded in isolating a highly pure complex of these proteins as part of his doctoral thesis at the University of Bochum. By applying cryo-electron microscopy and tomography, Pascal Lill at the MPI in Dortmund obtained the structure of the complex, which consists of elongated strands arranged parallel to each other, together forming an overall rod-like structure. Daniel Wendscheck, a doctoral student in the Research Training Group (RTG) 2202 'Transport across and into membranes' at the University of Freiburg, was able to determine with native mass spectrometry and chemical cross-linking that the complex is composed of a total of three copies of the Pex14p protein and one Pex17p. The groups' joint work reveals that the three Pex14p proteins show flexible areas that protrude into the cell like tentacles. The scientists suspect that the tentacles serve to 'fish' for as many loaded receptors as possible. "This complex is essential for functional peroxisomes," says Christos Gatsogiannis. "Our first picture of its structure and a mechanistic model of its function form an important basis for further studies of peroxisomes and could also contribute to a better understanding of peroxisomal diseases."