485 research outputs found
Formation of a Nematic Fluid at High Fields in Sr3Ru2O7
In principle, a complex assembly of strongly interacting electrons can
self-organise into a wide variety of collective states, but relatively few such
states have been identified in practice. We report that, in the close vicinity
of a metamagnetic quantum critical point, high purity Sr3Ru2O7 possesses a
large magnetoresistive anisotropy, consistent with the existence of an
electronic nematic fluid. We discuss a striking phenomenological similarity
between our observations and those made in high purity two-dimensional electron
fluids in GaAs devices.Comment: 14 pages, 3 figures, 11 extra pages of supplementary informatio
Superconducting Magnetization above the Irreversibility Line in Tl2Ba2CuO6
Piezolever torque magnetometry has been used to measure the magnetization of
superconducting Tl2Ba2CuO6. Three crystals with different levels of oxygen
overdoping were investigated in magnetic fields up to 10 Tesla. In all cases,
the magnetization above the irreversibility line was found to depart from the
behaviour M ~ ln(Hc2/H) of a simple London-like vortex liquid. In particular,
for a strongly overdoped (Tc = 15K) crystal, the remnant superconducting order
above the irreversibility line is characterized by a linear diamagnetic
response (M ~ H) that persists well above Tc and also up to the highest field
employed.Comment: RevTeX, 11 pages, 7 encapsulated PostScript figures, submitted to
Physical Review
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The use of drama to teach social skills in a special school setting for students with autism.
For children with autism, social challenges may be both part of the disability and a barrier to accessing education. This paper reports on a project which used drama to address such challenges by drawing on the social skills of non-autistic peers in a special school setting. The paper demonstrates how drama’s flexibility may be harnessed in order to help students support each other’s development of creative and communicative skills. Focusing on two children in particular, specific examples are given to illustrate how they participated in group work, made imaginative contributions to verbal and physical representations, and engaged with abstract ideas. The project’s outcomes suggest, given a concrete structure and an invitation to collaborate, drama can be a powerful learning medium for children with ASD. The conclusion reflects on the diverse meaning of inclusive practice which can be achieved within specialist settings
Crystal Structure of the N-Acetylmannosamine Kinase Domain of GNE
UDP-GlcNAc 2-epimerase/ManNAc 6-kinase, GNE, is a bi-functional enzyme that plays a key role in sialic acid biosynthesis. Mutations of the GNE protein cause sialurea or autosomal recessive inclusion body myopathy/Nonaka myopathy. GNE is the only human protein that contains a kinase domain belonging to the ROK (repressor, ORF, kinase) family.We solved the structure of the GNE kinase domain in the ligand-free state. The protein exists predominantly as a dimer in solution, with small populations of monomer and higher-order oligomer in equilibrium with the dimer. Crystal packing analysis reveals the existence of a crystallographic hexamer, and that the kinase domain dimerizes through the C-lobe subdomain. Mapping of disease-related missense mutations onto the kinase domain structure revealed that the mutation sites could be classified into four different groups based on the location - dimer interface, interlobar helices, protein surface, or within other secondary structural elements.The crystal structure of the kinase domain of GNE provides a structural basis for understanding disease-causing mutations and a model of hexameric wild type full length enzyme.This article can also be viewed as an enhanced version in which the text of the article is integrated with interactive 3D representations and animated transitions. Please note that a web plugin is required to access this enhanced functionality. Instructions for the installation and use of the web plugin are available in Text S1
Research Data Management in the Atlantic Provinces
Research Data Management (RDM) is becoming an increasingly important issue for post-secondary institutions. The Tri-Agencies (SSHRC, NSERC, CIHR) are expected to release a new policy that will stipulate that institutions have an institutional strategy for dealing with research data. Part of the responsibility will lie with researchers and the management of their research data.
Three Atlantic universities are aiming to discover how researchers are storing, using and sharing their data through administering a survey using an instrument that has been used at many Canadian universities. Surveys will be administered in Winter 2019. Data from the surveys will be analyzed separately by each institution and may be combined to identify commonalities and possibilities for collaboration in the region.
The results of these surveys will help librarians, IT specialists, data managers, and others interested in data management to understand current practices and attitudes. The results will also be used to contribute of the development of RDM services and resources across Atlantic post-secondary institutions with the aim of being prepared for the Tri-Agency policy once it comes into effect
How does study quality affect the results of a diagnostic meta-analysis?
Background: The use of systematic literature review to inform evidence based practice in diagnostics is rapidly expanding. Although the primary diagnostic literature is extensive, studies are often of low methodological quality or poorly reported. There has been no rigorously evaluated, evidence based tool to assess the methodological quality of diagnostic studies. The primary objective of this study was to determine the extent to which variations in the quality of primary studies impact the results of a diagnostic meta-analysis and whether this differs with diagnostic test type. A secondary objective was to contribute to the evaluation of QUADAS, an evidence-based tool for the assessment of quality in diagnostic accuracy studies. Methods: This study was conducted as part of large systematic review of tests used in the diagnosis and further investigation of urinary tract infection (UTI) in children. All studies included in this review were assessed using QUADAS, an evidence-based tool for the assessment of quality in systematic reviews of diagnostic accuracy studies. The impact of individual components of QUADAS on a summary measure of diagnostic accuracy was investigated using regression analysis. The review divided the diagnosis and further investigation of UTI into the following three clinical stages: diagnosis of UTI, localisation of infection, and further investigation of the UTI. Each stage used different types of diagnostic test, which were considered to involve different quality concerns. Results: Many of the studies included in our review were poorly reported. The proportion of QUADAS items fulfilled was similar for studies in different sections of the review. However, as might be expected, the individual items fulfilled differed between the three clinical stages. Regression analysis found that different items showed a strong association with test performance for the different tests evaluated. These differences were observed both within and between the three clinical stages assessed by the review. The results of regression analyses were also affected by whether or not a weighting (by sample size) was applied. Our analysis was severely limited by the completeness of reporting and the differences between the index tests evaluated and the reference standards used to confirm diagnoses in the primary studies. Few tests were evaluated by sufficient studies to allow meaningful use of meta-analytic pooling and investigation of heterogeneity. This meant that further analysis to investigate heterogeneity could only be undertaken using a subset of studies, and that the findings are open to various interpretations. Conclusion: Further work is needed to investigate the influence of methodological quality on the results of diagnostic meta-analyses. Large data sets of well-reported primary studies are needed to address this question. Without significant improvements in the completeness of reporting of primary studies, progress in this area will be limited
Risky Business: Reopening Recreational Sport Facilities During COVID-19
At the onset of COVID-19, sport and fitness administrators shut down facilities to mitigate viral spread. To reopen facilities, safety protocols and policies reflecting risk mitigation strategies were established. This case study adopted the International Standards Organization’s risk management framework to explore strategies for reopening collegiate recreational sport facilities during the pandemic. Document analysis was employed to analyze the reopening plans of four collegiate recreation departments across North America. The reopening plans focused on the risk assessment and treatment process and used a phased approach, with strategies moving from risk avoidance to risk reduction and transfer. Common risk management strategies across facility areas included social distancing, reduced programming/services, and increased sanitization. However, notable differences were found based on risk unique to distinct facility areas. Implications for practice include use of a customized facility inspection checklist, adherence to new industry safety standards, and clear communication with stakeholders
Pathogenic marine microbes influence the effects of climate change on a commercially important tropical bivalve
There is growing evidence that climate change will increase the prevalence of toxic algae and harmful bacteria, which can accumulate in marine bivalves. However, we know little about any possible interactions between exposure to these microorganisms and the effects of climate change on bivalve health, or about how this may affect the bivalve toxin-pathogen load. In mesocosm experiments, mussels, Perna viridis, were subjected to simulated climate change (warming and/or hyposalinity) and exposed to harmful bacteria and/or toxin-producing dinoflagellates. We found significant interactions between climate change and these microbes on metabolic and/or immunobiological function and toxin-pathogen load in mussels. Surprisingly, however, these effects were virtually eliminated when mussels were exposed to both harmful microorganisms simultaneously. This study is the first to examine the effects of climate change on determining mussel toxin-pathogen load in an ecologically relevant, multi-trophic context. The results may have considerable implications for seafood safety
Reprocessing with GANEX:Methodology for Ligand Radiation Tolerance Testing
Results demonstrating the methodology for testing the radiation tolerance of organic ligands are presented. A high activity sealed source was used to irradiate samples which were sequentially removed and analysed using a sensitive mass spectrometer. The degradation of a candidate ligand for a new reprocessing process “GANEX” was found to be around 50% after 567 kGy exposure to gamma from Cs-137.<br/
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