1,920 research outputs found

    Emergence of macrolide-resistant Mycoplasma pneumoniae in Hong Kong is linked to increasing macrolide resistance in the multilocus variable-number tandem-repeat analysis type 4-5-7-2

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    Macrolide-resistant Mycoplasma pneumoniae (MRMP) is rapidly emerging in Asia, but information on the temporal relationship between the increase in macrolide resistance and changes in strain types is scarce. Between 2011 and 2014, M. pneumoniae infection was diagnosed by PCR as part of routine care in a health care region in Hong Kong. Testing was initiated by clinicians, mainly in patients with suspected M. pneumoniae pneumonia. Specimens positive for M. pneumoniae were retrospectively investigated by macrolide resistance genotyping and a four-locus (Mpn13 to-16) multilocus variable-number tandem-repeat analysis (MLVA) scheme. The overall percentage of M. pneumoniae-positive specimens was 17.9%, with annual rates ranging from 9.8% to 27.2%. The prevalence of MRMP had rapidly increased from 13.6% in 2011 to 30.7% in 2012, 36.6% in 2013, and 47.1% in 2014 (P=0.038). Two major MLVA types, 4-5-7-2 and 3-5-6-2, accounted for 75% to 85% of the infections each year. MLVA types 4-5-7-2 and 3-5-6-2 predominated among macrolide-resistant and macrolide-sensitive groups, respectively. The increase in MRMP was mainly caused by increasing macrolide resistance in the prevalent MLVA type 4-5-7-2, changing from 25.0% in 2011 to 59.1% in 2012, to 89.7% in 2013, and to 100% in 2014 (P<0.001). In conclusion, increasing MRMP in Hong Kong was linked to a single MLVA type, which was both prevalent and increasingly resistant to macrolides. Copyright © 2015, American Society for Microbiology. All Rights Reserved.postprin

    Planar Hall effect from the surface of topological insulators

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    A prominent feature of topological insulators (TIs) is the surface states comprising of spin-nondegenerate massless Dirac fermions. Recent technical advances have made it possible to address the surface transport properties of TI thin films by tuning the Fermi levels of both top and bottom surfaces. Here we report our discovery of a novel planar Hall effect (PHE) from the TI surface, which results from a hitherto-unknown resistivity anisotropy induced by an in-plane magnetic field. This effect is observed in dual-gated devices of bulk-insulating Bi2−x Sb x Te3 thin films, where the field-induced anisotropy presents a strong dependence on the gate voltage with a characteristic two-peak structure near the Dirac point. The origin of PHE is the peculiar time-reversal-breaking effect of an in-plane magnetic field, which anisotropically lifts the protection of surface Dirac fermions from backscattering. The observed PHE provides a useful tool to analyze and manipulate the topological protection of the TI surface

    Conceptualizing pathways linking women's empowerment and prematurity in developing countries.

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    BackgroundGlobally, prematurity is the leading cause of death in children under the age of 5. Many efforts have focused on clinical approaches to improve the survival of premature babies. There is a need, however, to explore psychosocial, sociocultural, economic, and other factors as potential mechanisms to reduce the burden of prematurity. Women's empowerment may be a catalyst for moving the needle in this direction. The goal of this paper is to examine links between women's empowerment and prematurity in developing settings. We propose a conceptual model that shows pathways by which women's empowerment can affect prematurity and review and summarize the literature supporting the relationships we posit. We also suggest future directions for research on women's empowerment and prematurity.MethodsThe key words we used for empowerment in the search were "empowerment," "women's status," "autonomy," and "decision-making," and for prematurity we used "preterm," "premature," and "prematurity." We did not use date, language, and regional restrictions. The search was done in PubMed, Population Information Online (POPLINE), and Web of Science. We selected intervening factors-factors that could potentially mediate the relationship between empowerment and prematurity-based on reviews of the risk factors and interventions to address prematurity and the determinants of those factors.ResultsThere is limited evidence supporting a direct link between women's empowerment and prematurity. However, there is evidence linking several dimensions of empowerment to factors known to be associated with prematurity and outcomes for premature babies. Our review of the literature shows that women's empowerment may reduce prematurity by (1) preventing early marriage and promoting family planning, which will delay age at first pregnancy and increase interpregnancy intervals; (2) improving women's nutritional status; (3) reducing domestic violence and other stressors to improve psychological health; and (4) improving access to and receipt of recommended health services during pregnancy and delivery to help prevent prematurity and improve survival of premature babies.ConclusionsWomen's empowerment is an important distal factor that affects prematurity through several intervening factors. Improving women's empowerment will help prevent prematurity and improve survival of preterm babies. Research to empirically show the links between women's empowerment and prematurity is however needed

    Performance of the CMS Cathode Strip Chambers with Cosmic Rays

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    The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

    Parents’ marital status and child physical abuse potential: the mediation of depression symptoms

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    Informed by a social interactional framework of stress and parenting, the aim of this study was to examine the mediating effect of depression symptoms on the asso- ciation between parents’ marital status (married and divorced parents) and child physical abuse potential, in a Portuguese community sample. It was hypothesized that the possible observed differences between divorced and married parents in the child physical abuse potential would be explained by their depression symptoms. Parents (N = 892) were assessed in their marital status, severity of depression symptoms and child physical abuse potential. Results showed that, when compared with married parents, divorced parents had higher child physical abuse potential. However, parents’ depression symptomatology was found as a mediator of the effect of marital status differences on child physical abuse potential. The influence of the status of divorced parents on the increase of child physical abuse potential was explained by the increase of the parents’ depression symptoms. This finding suggested that parents’ divorced status had no longer an effect on child physical abuse potential when parents’ depression symptomatology was tested as a mediator vari- able. The present mediation model explained 47 % of the variability in the child physical abuse potential score. Prac- tical implications of these findings for prevention and psy- chological intervention are also discussed.info:eu-repo/semantics/publishedVersio

    Toll-Like Receptor 8 Agonist and Bacteria Trigger Potent Activation of Innate Immune Cells in Human Liver

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    This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The study was supported by a Grant core funding from the Agency for Science Technology and Research (A*STAR, Singapore) and a Singapore Translational Research Investigator Award (NRMC/StaR/013/2012) to AB as well as NIHR Biomedical Centre, Oxford, WT 091663MA, NIAID1U19AI082630-01, Oxford Martin School funding and an NIHR Senior Investigator award to PK

    Properties of Graphene: A Theoretical Perspective

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    In this review, we provide an in-depth description of the physics of monolayer and bilayer graphene from a theorist's perspective. We discuss the physical properties of graphene in an external magnetic field, reflecting the chiral nature of the quasiparticles near the Dirac point with a Landau level at zero energy. We address the unique integer quantum Hall effects, the role of electron correlations, and the recent observation of the fractional quantum Hall effect in the monolayer graphene. The quantum Hall effect in bilayer graphene is fundamentally different from that of a monolayer, reflecting the unique band structure of this system. The theory of transport in the absence of an external magnetic field is discussed in detail, along with the role of disorder studied in various theoretical models. We highlight the differences and similarities between monolayer and bilayer graphene, and focus on thermodynamic properties such as the compressibility, the plasmon spectra, the weak localization correction, quantum Hall effect, and optical properties. Confinement of electrons in graphene is nontrivial due to Klein tunneling. We review various theoretical and experimental studies of quantum confined structures made from graphene. The band structure of graphene nanoribbons and the role of the sublattice symmetry, edge geometry and the size of the nanoribbon on the electronic and magnetic properties are very active areas of research, and a detailed review of these topics is presented. Also, the effects of substrate interactions, adsorbed atoms, lattice defects and doping on the band structure of finite-sized graphene systems are discussed. We also include a brief description of graphane -- gapped material obtained from graphene by attaching hydrogen atoms to each carbon atom in the lattice.Comment: 189 pages. submitted in Advances in Physic
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