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Summary: Background: COVID-19 has the potential to cause outbreaks in hospitals. Given the comorbid and elderly cohort of patients hospitalized, hospital-acquired COVID-19 infection is often fatal. Pathogen genome sequencing is becoming increasingly important in infection prevention and control (IPC). Aim: To inform the understanding of in-hospital SARS-CoV-2 transmission in order to improve IPC practices and to inform the future development of virological testing for IPC. Methods: Patients detected COVID-19 positive by polymerase chain reaction on Ward A in April and May 2020 were included with contact tracing to identify other potential cases. Genome sequencing was undertaken for a subgroup of cases. Epidemiological, genomic, and cluster analyses were performed to describe the epidemiology and to identify factors contributing to the outbreak. Findings: Fourteen cases were identified on Ward A. Contact tracing identified 16 further patient cases; in addition, eight healthcare workers (HCWs) were identified as being COVID-19 positive through a round of asymptomatic testing. Genome sequencing of 16 of these cases identified viral genomes differing by two single nucleotide polymorphisms or fewer, with further cluster analysis identifying two groups of infection (a five-person group and a six-person group). Conclusion: Despite the temporal relationship of cases, genome sequencing identified that not all cases shared transmission events. However, 11 samples were found to be closely related and these likely represented in-hospital transmission. This included three HCWs, thereby confirming transmission between patients and HCWs.

Abstract Background The genetic diversity in Australian populations of Xanthomonas species associated with bacterial leaf spot in tomato, capsicum and chilli were compared to worldwide bacterial populations. The aim of this study was to confirm the identities of these Australian Xanthomonas species and classify them in comparison to overseas isolates. Analysis of whole genome sequence allows for the investigation of bacterial population structure, pathogenicity and gene exchange, resulting in better management strategies and biosecurity. Results Phylogenetic analysis of the core genome alignments and SNP data grouped strains in distinct clades. Patterns observed in average nucleotide identity, pan genome structure, effector and carbohydrate active enzyme profiles reflected the whole genome phylogeny and highlight taxonomic issues in X. perforans and X. euvesicatoria. Circular sequences with similarity to previously characterised plasmids were identified, and plasmids of similar sizes were isolated. Potential false positive and false negative plasmid assemblies were discussed. Effector patterns that may influence virulence on host plant species were analysed in pathogenic and non-pathogenic xanthomonads. Conclusions The phylogeny presented here confirmed X. vesicatoria, X. arboricola, X. euvesicatoria and X. perforans and a clade of an uncharacterised Xanthomonas species shown to be genetically distinct from all other strains of this study. The taxonomic status of X. perforans and X. euvesicatoria as one species is discussed in relation to whole genome phylogeny and phenotypic traits. The patterns evident in enzyme and plasmid profiles indicate worldwide exchange of genetic material with the potential to introduce new virulence elements into local bacterial populations.

In deep inelastic multinucleon transfer reactions of 48Ca + 248Cm we observed about 100 residual nuclei with proton numbers between Z=82 and Z=100. Among them, there are five new neutron-deficient isotopes: 216U, 219Np, 223Am, 229Am and 233Bk. As separator for the transfer products we used the velocity filter SHIP of GSI while the isotope identification was performed via the α decay chains of the nuclei. These first results reveal that multinucleon transfer reactions together with here applied fast and sensitive separation and detection techniques are promising for the synthesis of new isotopes in the region of heaviest nuclei.

Abstract The sequence of events associated with the triggering of energy release during substorm expansion phase onset is still not well‐understood. Oberhagemann and Mann (2020b, https://doi.org/10.1029/2019gl085271) proposed a new substorm onset mechanism, where the transition toward parallel proton pressure anisotropy during tail stretching in the late growth phase could trigger a pressure anisotropic ballooning instability. Here we examine the evolution of energetic proton parallel pressure anisotropy at geosynchronous altitudes, seeking evidence in support of the proposed substorm onset mechanism. We use the Geostationary Operational Environment Satellite (GOES) proton flux and magnetometer data combined with substorm onset indicators derived from ground‐based magnetometers. Superposed epoch analysis of substorm onset times for 2014 using the isolated substorm list (Ohtani & Gjerloev, 2020, https://doi.org/10.1029/2020ja027902) clearly shows signatures of energetic proton parallel pressure anisotropy immediately before substorm onset, potentially supportive of the Oberhagemann and Mann theory.

Abstract Background Point mutations in histone variant H3.3 (H3.3K27M, H3.3G34R) and the H3.3-specific ATRX/DAXX chaperone complex are frequent events in pediatric gliomas. These H3.3 point mutations affect many chromatin modifications but the exact oncogenic mechanisms are currently unclear. Histone H3.3 is known to localize to nuclear compartments known as promyelocytic leukemia (PML) nuclear bodies, which are frequently mutated and confirmed as oncogenic drivers in acute promyelocytic leukemia. Results We find that the pediatric glioma-associated H3.3 point mutations disrupt the formation of PML nuclear bodies and this prevents differentiation down glial lineages. Similar to leukemias driven by PML mutations, H3.3-mutated glioma cells are sensitive to drugs that target PML bodies. We also find that point mutations in IDH1/2—which are common events in adult gliomas and myeloid leukemias—also disrupt the formation of PML bodies. Conclusions We identify PML as a contributor to oncogenesis in a subset of gliomas and show that targeting PML bodies is effective in treating these H3.3-mutated pediatric gliomas.

Objectives: To quantify the number and type of students failing to secure basic needs. Participants: Students attending 22 postsecondary schools in the United States in Fall 2019. Methods: The Adult Food Security Module and part of the #RealCollege Survey were used to measure food and housing insecurity, respectively. Logistic and linear regression models were used to assess the relationship between selected factors and basic needs insecurities. Results: Participants (n = 22,153) were classified as 44.1% and 52.3% food insecure and housing insecure, respectively. Homeless students or those who experienced childhood food insecurity were at the greatest odds of college food insecurity. Year in school was the largest contributor to being housing insecure, with PhD or EdD students being 1,157% more likely to experience housing insecurity compared to freshmen. Conclusions: High prevalence of basic needs insecurities remain. Current campus initiatives may be insufficient, calling for a more holistic approach at the campus, state, and national levels.

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Abstract In the face of the global biodiversity crisis, collecting comprehensive data and making the best use of existing data are becoming increasingly important to understand patterns and drivers of environmental and biological phenomena at different scales. Here we address the concept of secondary data, which refers to additional information unintentionally captured in species records, especially in multimedia‐based citizen science reports. We argue that secondary data can provide a wealth of ecologically relevant information, the utilisation of which can enhance our understanding of traits and interactions among individual organisms, populations and biodiversity dynamics in general. We explore the possibilities offered by secondary data and describe their main types and sources. An overview of research in this field provides a synthesis of the results already achieved using secondary data and different approaches to information extraction. Finally, we discuss challenges to the widespread use of secondary data, such as biases, licensing issues, use of metadata and lack of awareness of this trove of data due to a missing common terminology, as well as possible solutions to overcome these barriers. Although the exploration and use of secondary data is only emerging, the many opportunities identified show how these data can enrich biodiversity research and monitoring.

Abstract Understanding intense electron precipitation is crucial for characterizing radiation belt loss and assessing related impacts on the atmosphere. We investigate the evolution of electron flux during an ensemble of 70 geomagnetic storms, focusing on equatorial and low‐Earth orbit observations of trapped and precipitating ∼30–100 keV energy electrons. We reveal that the most intense electron precipitation is associated with equatorial flux capping through self‐limiting processes, for example, as described theoretically by Kennel and Petschek (1966, https://doi.org/10.1029/jz071i001p00001). Our results indicate that the most intense electron precipitation is caused by electron injections associated with self‐limiting processes. Dawn side injections are observed to have fluxes that exceed the Kennel‐Petschek limit, consistent with the excitation of strong chorus waves and resulting in intense precipitation and return of the trapped flux to the Kennel‐Petschek limit. Our results clearly demonstrate the important role of self‐limiting processes in affecting the dynamics of newly injected electrons and driving intense electron precipitation.

The structure of pore spaces in typical catalyst particles could often be described as being “not so much fabricated as thrown together”. Thus whilst for certain materials, such as zeolites, the microstructures are well defined and have a precise geometry, most materials when used in typical particulate form are at least partly composed of chaotically configured pore spaces. These random pore structures can be important in determining an adsorbent's performance, so it is necessary to define them quantitatively. A heirarchy of approaches based upon developments from simple stochastic pore networks is described. A stochastic pore network is one in which simple pore segments form interconnecting networks within which pores can be either randomly or partly randomly distributed. Such stochastic networks can be characterised by mercury porosimetry and low-temperature gas adsorption. Interconnectivity and randomness affect the degree of hysteresis for both these techniques. For 3-D random pattern stochastic networks, it is possible to interpret sectioned SEM images using ‘random’ slices of particles subject to low melting point alloy visual porosimetry in order to arrive at measures of random pore structure. This ‘image analysis’ approach is being extended to 3-D image reconstruction of SEM sections using fractal surfaces in conjunction with randomly tortuous pores.

JWST has ushered in an era of unprecedented ability to characterize exoplanetary atmospheres. While there are over 5000 confirmed planets, more than 4000 Transiting Exoplanet Survey Satellite (TESS) planet candidates are still unconfirmed and many of the best planets for atmospheric characterization may remain to be identified. We present a sample of TESS planets and planet candidates that we identify as “best-in-class” for transmission and emission spectroscopy with JWST. These targets are sorted into bins across equilibrium temperature T _eq and planetary radius R _p and are ranked by a transmission and an emission spectroscopy metric (TSM and ESM, respectively) within each bin. We perform cuts for expected signal size and stellar brightness to remove suboptimal targets for JWST. Of the 194 targets in the resulting sample, 103 are unconfirmed TESS planet candidates, also known as TESS Objects of Interest (TOIs). We perform vetting and statistical validation analyses on these 103 targets to determine which are likely planets and which are likely false positives, incorporating ground-based follow-up from the TESS Follow-up Observation Program to aid the vetting and validation process. We statistically validate 18 TOIs, marginally validate 31 TOIs to varying levels of confidence, deem 29 TOIs likely false positives, and leave the dispositions for four TOIs as inconclusive. Twenty-one of the 103 TOIs were confirmed independently over the course of our analysis. We intend for this work to serve as a community resource and motivate formal confirmation and mass measurements of each validated planet. We encourage more detailed analysis of individual targets by the community.

Abstract On 7 January 2014, a solar storm erupted, which eventually compressed the Earth's magnetosphere leading to the generation of chorus waves. These waves enhanced local wave‐particle interactions and led to the precipitation of electrons from 10 s eV to 100 s keV. This paper shows observations of a low energy cutoff in the precipitation spectrum from Van Allen Probe B Helium Oxygen Proton Electron measurements. This low energy cutoff is well replicated by the predicted loss calculated from pitch angle diffusion coefficients from wave and plasma observations on Probe B. To our knowledge, this is the first time a single spacecraft has been used to demonstrate an accurate theoretical prediction for chorus wave‐induced precipitation and its low energy cutoff. The specific properties of the precipitating soft electron spectrum have implications for ionospheric activity, with the lowest energies mainly contributing to thermospheric and ionospheric upwelling, which influences satellite drag and ionospheric outflow.

This introduction to the special issue provides an overview of the status of transitions from care in Canada. Currently, few statistics are collected on youth in and from care and regional disparities contribute to a comparatively low level of services overall, as well as a fragmented approach to policies outlining the rights of those who have grown up in government care. The contributions in the issue exemplify the growing interest in care leaving research and theory building in Canada, as well as the significant advocacy provided by care-experienced youth leaders , all of which augur well for the future of care leaving across the country.

Objective: In Athletics (Track and Field), athletes can be affected by injuries, especially in their quest for top performance. Therefore, we aim to provide an overview of the current knowledge about the problem of injuries in Athletics. Main findings: It is necessary to maintain a clear definition of "injury" when stakeholders in Athletics discuss clinical, administrative, and/or research perspectives. There are several possible methodological approaches to collect injury data in Athletics depending on the context, population, and injury definition. In general, about two thirds of Athletics athletes sustain at least one injury during an Athletics season, and there are about 100 injuries per 1000 registered athletes during an international championship. The injury rates and characteristics vary by sex and discipline. The injuries can affect athletes physically, psychologically, and socially, with short- and long-term consequences for musculoskeletal function, athletics performance and athletics career. Although it is logical to try to reduce the injury risk, little scientific evidence is currently available to help Athletics-related stakeholders. Conclusions: Injury can currently be considered as an omnipresent problem in Athletics, which affects their practice, with consequences on performance and health. Injury risk is today an undeniable part of the life of Athletics athletes, which implies that there is a pressing need to continue the development of injury risk reduction strategies, to scientifically evaluate their efficacy, and to implement them in sports practice. [ABSTRACT FROM AUTHOR]

Abstract Ground‐based Pc5 ultralow frequency (ULF) wave power in multiple ground‐based meridians is compared to the very low frequency (VLF) wave amplitude proxy, derived from Polar Operational Environmental Satellite (POES) precipitation, for the 33 storms studied by Li et al. (2015, https://doi.org/10.1002/2015GL065342). The results reveal common L‐shell and time profiles for the ULF waves and VLF proxy for every single storm, especially at L ≤ 6, and identical discrimination between efficient and inefficient radiation belt electron acceleration. The observations imply either ULF waves play a role in driving precipitation, which is falsely interpreted as VLF wave power in the proxy, ULF waves drive VLF waves (the reverse being energetically unfeasible), or both have a common driver with nearly identical L‐shell and time dependence. Global ground‐based ULF wave power coherence implies that a small number of meridians can be used to estimate storm time radial diffusion coefficients. However, the strong correspondence between ULF wave power and VLF wave proxy complicates causative assessments of electron acceleration.

Capstone courses often focus on applied learning, typically practicum experiences such as internships. However, students do not always benefit as much as they could from their internships because teaching and learning resources are not used optimally. This paper explores the use of project-based learning in a capstone course of the Graduate Diploma in Youth Work program at Concordia University that includes an in-class seminar and an internship in a human services agency. Using the principles of context authenticity and cognitive apprenticeship from the Authentic Situated Learning and Teaching (ASLT) framework, we examine the experiences of two cohorts of interns (24 students in all). An analysis of their final papers and participation in a focus group, as well as the results of the university’s course evaluation, suggests that the ASLT framework contributes to the transfer of learning in a professional setting. Furthermore, the use of the psychoeducative model to structure active pedagogies in a youth work capstone course provides a means for planning therapeutic activities and organizing intervention programs that help develop competencies to work in diverse settings.

This report describes the evolution of an independent youth-led organization for youth in and from care in Quebec. The emergence of CARE Jeunesse is presented and compared with two other networks in Canada. Factors that promoted and hindered its development are discussed particularly as they apply to issues outlined in the youth engagement literature. The board of CARE Jeunesse, comprising former youth in care, wrote this article with the participation of a university professor who is an adult ally to the alumni of care movement in Quebec. This report is the first publication that provides an account of the processes associated with developing a youth in care network in Canada.