317 research outputs found

    Periodontal status in mothers with or without spontaneous preterm births

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    Enhanced electrochemical reduction of hydrogen peroxide by Co3O4 nanowire electrode

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    Crystalline Co3O4 nanowire arrays with different morphologies grown on Ni foam were investigated by varying the reaction temperature, the concentration of precursors, and reaction time. The Co3O4 nanowires synthesized under typical reaction condition had a diameter range of approximately 500–900 nm with a length of 17 µm. Electrochemical reduction of hydrogen peroxide (H2O2) of the optimized Co3O4 nanowire electrode was studied by cyclic voltammetry. A high current density of 101.8 mA cm−2 was obtained at −0.4 V in a solution of 0.4 M H2O2 and 3.0 M NaOH at room temperature compared to 85.8 mA cm−2 at −0.35 V of the Co3O4 nanoparticle electrode. Results clearly indicated that the Ni foam supported Co3O4 nanowire electrode exhibited superior catalytic activity and mass transport kinetics for H2O2 electrochemical reduction

    Synthesis of Novel Double-Layer Nanostructures of SiC–WOxby a Two Step Thermal Evaporation Process

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    A novel double-layer nanostructure of silicon carbide and tungsten oxide is synthesized by a two-step thermal evaporation process using NiO as the catalyst. First, SiC nanowires are grown on Si substrate and then high density W18O49nanorods are grown on these SiC nanowires to form a double-layer nanostructure. XRD and TEM analysis revealed that the synthesized nanostructures are well crystalline. The growth of W18O49nanorods on SiC nanowires is explained on the basis of vapor–solid (VS) mechanism. The reasonably better turn-on field (5.4 V/μm) measured from the field emission measurements suggest that the synthesized nanostructures could be used as potential field emitters

    Plants used during pregnancy, childbirth and postpartum healthcare in Lao PDR: A comparative study of the Brou, Saek and Kry ethnic groups

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    <p>Abstract</p> <p>Background</p> <p>In many Southeast Asian cultures the activities and diet during the postpartum period are culturally dictated and a period of confinement is observed. Plants play an important role in recovery during the postpartum period in diet, traditional medicine, steam bath and mother roasting (where mother and child placed on a bed above a brazier with charcoal embers on which aromatic plants are laid). This research focuses on the use of plants during pregnancy, parturition, postpartum recovery and infant healthcare among three ethnic groups, the Brou, Saek and Kry. It aims to identify culturally important traditions that may facilitate implementation of culturally appropriate healthcare.</p> <p>Methods</p> <p>Data were collected in 10 different villages in Khammouane province, Lao PDR, through group and individual interviews with women by female interviewers.</p> <p>Results</p> <p>A total of 55 different plant species are used in women's healthcare, of which over 90% are used in postpartum recovery. Consensus Analysis rejects the hypothesis that the three ethnic groups belong to a single culture for postpartum plant use, and multidimensional scaling reveals non-overlapping clusters per ethnic group.</p> <p>Conclusion</p> <p>Medicinal plant use is common among the Brou, Saek and Kry to facilitate childbirth, alleviate menstruation problems, assist recovery after miscarriage, mitigate postpartum haemorrhage, aid postpartum recovery, and for use in infant care. The wealth of novel insights into plant use and preparation will help to understand culturally important practices such as confinement, dietary restrictions, mother roasting and herbal steam baths and their incorporation into modern healthcare.</p

    Assessing the digenic model in rare disorders using population sequencing data

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    An important fraction of patients with rare disorders remains with no clear genetic diagnostic, even after whole-exome or whole-genome sequencing, posing a difficulty in giving adequate treatment and genetic counseling. The analysis of genomic data in rare disorders mostly considers the presence of single gene variants in coding regions that follow a concrete monogenic mode of inheritance. A digenic inheritance, with variants in two functionally-related genes in the same individual, is a plausible alternative that might explain the genetic basis of the disease in some cases. In this case, digenic disease combinations should be absent or underrepresented in healthy individuals. We develop a framework to evaluate the significance of digenic combinations and test its statistical power in different scenarios. We suggest that this approach will be relevant with the advent of new sequencing efforts including hundreds of thousands of samples

    Meiotic Recombination Intermediates Are Resolved with Minimal Crossover Formation during Return-to-Growth, an Analogue of the Mitotic Cell Cycle

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    Accurate segregation of homologous chromosomes of different parental origin (homologs) during the first division of meiosis (meiosis I) requires inter-homolog crossovers (COs). These are produced at the end of meiosis I prophase, when recombination intermediates that contain Holliday junctions (joint molecules, JMs) are resolved, predominantly as COs. JM resolution during the mitotic cell cycle is less well understood, mainly due to low levels of inter-homolog JMs. To compare JM resolution during meiosis and the mitotic cell cycle, we used a unique feature of Saccharomyces cerevisiae, return to growth (RTG), where cells undergoing meiosis can be returned to the mitotic cell cycle by a nutritional shift. By performing RTG with ndt80 mutants, which arrest in meiosis I prophase with high levels of interhomolog JMs, we could readily monitor JM resolution during the first cell division of RTG genetically and, for the first time, at the molecular level. In contrast to meiosis, where most JMs resolve as COs, most JMs were resolved during the first 1.5–2 hr after RTG without producing COs. Subsequent resolution of the remaining JMs produced COs, and this CO production required the Mus81/Mms4 structure-selective endonuclease. RTG in sgs1-ΔC795 mutants, which lack the helicase and Holliday junction-binding domains of this BLM homolog, led to a substantial delay in JM resolution; and subsequent JM resolution produced both COs and NCOs. Based on these findings, we suggest that most JMs are resolved during the mitotic cell cycle by dissolution, an Sgs1 helicase-dependent process that produces only NCOs. JMs that escape dissolution are mostly resolved by Mus81/Mms4-dependent cleavage that produces both COs and NCOs in a relatively unbiased manner. Thus, in contrast to meiosis, where JM resolution is heavily biased towards COs, JM resolution during RTG minimizes CO formation, thus maintaining genome integrity and minimizing loss of heterozygosity

    Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

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    The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

    Measurement and interpretation of same-sign W boson pair production in association with two jets in pp collisions at s = 13 TeV with the ATLAS detector

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    This paper presents the measurement of fducial and diferential cross sections for both the inclusive and electroweak production of a same-sign W-boson pair in association with two jets (W±W±jj) using 139 fb−1 of proton-proton collision data recorded at a centre-of-mass energy of √s = 13 TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed by selecting two same-charge leptons, electron or muon, and at least two jets with large invariant mass and a large rapidity diference. The measured fducial cross sections for electroweak and inclusive W±W±jj production are 2.92 ± 0.22 (stat.) ± 0.19 (syst.)fb and 3.38±0.22 (stat.)±0.19 (syst.)fb, respectively, in agreement with Standard Model predictions. The measurements are used to constrain anomalous quartic gauge couplings by extracting 95% confdence level intervals on dimension-8 operators. A search for doubly charged Higgs bosons H±± that are produced in vector-boson fusion processes and decay into a same-sign W boson pair is performed. The largest deviation from the Standard Model occurs for an H±± mass near 450 GeV, with a global signifcance of 2.5 standard deviations
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