2,352 research outputs found

    Scintillation observations at Ancon and Jicamarca Observatories

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    Satellite scintillation and diffraction pattern scale size distribution from ionospheric irregularitie

    Statistical characteristics of low-latitude ionospheric field-aligned irregularities obtained with the Piura VHF radar

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    International audienceWe present a summary of the statistical characteristics of echoes from ionospheric (E- and F-region) field-aligned irregularities obtained with the Piura VHF radar. This radar is located at ~ 7.0° dip latitude, just outside the equatorial electrojet (EEJ) region. Our results are based on (1) intermittent observations made between 1991 and 1999 just few days a year, and (2) continuous observations made between January 2000 and June 2001. During most of the intermittent observations, simultaneous measurements of EEJ and equatorial spread F (ESF) irregularities were performed with the Jicamarca VHF radar. From the continuous measurements, we have obtained the diurnal and seasonal characteristics of a variety of parameters (percentage of occurrence, signal-to-noise ratio and/or Doppler velocities) from the lower and upper E-region irregularities and also from F-region irregularities over Piura. For example, we have found that (1) the E-region echoes are stronger and occur more frequently during local summer (i.e. between December and March); (2) between May and June, the E-region echoes are weaker and occur less frequently; moreover, during these months, a semidiurnal wave with large amplitudes is observed in the meridional wind (> 100 ms- 1); (3) there is vertical wavelength of about 20 km in the Doppler velocity, particularly after midnight; (4) the lower (upper) E-region Doppler velocities are influenced mainly by meridional winds (equatorial F-region vertical drifts). In addition, we have observed that the seasonal and daily occurrences of Piura F-region irregularities are similar to the occurrence of topside ESF irregularities over Jicamarca. The likelihood of occurrence of F-region irregularities over Piura and, therefore, topside ESF over Jicamarca is greater when there are no E-region irregularities over Piura. On the other hand, there is more probability of observing bottomtype/bottomside ESF irregularities over Jicamarca when E-region irregularities are observed over Piura

    Measuring disadvantage in the early years in the UK: A systematic scoping review

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    Background: The relationship between disadvantage and child health in the early years is well established. For this evidence base to most helpfully inform services, we need to better understand how disadvantage is conceptualised and measured in the literature. We aimed to conceptualise disadvantage measured in child health literature and explore the associations between disadvantage and child health using these measures. Method: We conducted a scoping review using systematic methods to identify key concepts of disadvantage used in empirical child health literature. We searched MEDLINE, Scopus, and grey literature for studies exploring the association between disadvantage and child health outcomes for children aged 0-5 in the United Kingdom. We extracted and analysed data from 86 studies. Results: We developed a framework describing two domains, each with two attributes conceptualising disadvantage: level of disadvantage indicator (individual and area) and content of disadvantage indicator (social and economic). Individual-level measures of disadvantage tended to identify stronger associations between disadvantage and child health compared with area-level measures. Conclusion: The choice of disadvantage indicators, particularly whether individual- or area-level, can affect the inferences made about the relationship between disadvantage and child health. Better access to individual-level disadvantage indicators in administrative data could support development and implementation of interventions aimed at reducing child health inequalities in the early years

    Naturally enhanced ion-line spectra around the equatorial 150-km region

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    For many years strong radar echoes coming from 140–170 km altitudes at low latitudes have been associated to the existence of field-aligned irregularities (FAIs) (the so called 150-km echoes). In this work, we present frequency spectra as well as angular distribution of 150-km echoes. When the 150-km region is observed with beams perpendicular to the magnetic field (<B>B</B>) the observed radar spectra are very narrow with spectral widths between 3–12 m/s. On the other hand, when few-degrees off-perpendicular beams are used, the radar spectra are wide with spectral widths comparable to those expected from ion-acoustic waves at these altitudes (>1000 m/s). Moreover the off-perpendicular spectral width increases with increasing altitude. The strength of the received echoes is one to two orders of magnitude stronger than the expected level of waves in thermal equilibrium at these altitudes. Such enhancement is not due to an increase in electron density. Except for the enhancement in power, the spectra characteristics of off-perpendicular and perpendicular echoes are in reasonable agreement with expected incoherent scatter spectra at these angles and altitudes. 150-km echoes are usually observed in narrow layers (2 to 5). Bistatic common volume observations as well as observations made few kilometers apart show that, for most of the layers, there is very high correlation on power fluctuations without a noticeable time separation between simultaneous echoes observed with Off-perpendicular and Perpendicular beams. However, in one of the central layers, the echoes are the strongest in the perpendicular beam and absent or very weak in the off-perpendicular beams, suggesting that they are generated by a plasma instability. Our results indicate that most echoes around 150-km region are not as aspect sensitive as originally thought, and they come from waves that have been enhanced above waves in thermal equilibrium

    Comparison of traps and baits for censusing small mammals in Neotropical lowlands.

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    Snap-traps, live-traps, and baits affect the ability to capture small mammals, but few previous studies have involved sampling communities of small mammals in tropical environments. We tested differences in captures of small marsupials and rodents by Victor snap-traps versus Sherman live-traps and by two types of bait in lowland rainforest at Reserva Cuzco AmazĂłnico, southeastern Peru. Snap-traps took ca. 3.5 times as many individuals as live-traps. Snap-traps also captured more species (and more rare species), but we attribute this to more numerous captures overall because the relative proportions of species captured by the two traps generally were the same. Type of bait had little impact on our trapping results

    The impact of a pilot continuing professional development module on hospital pharmacists’ preparedness to provide contemporary advice on the clinical use of vancomycin

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    This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.BACKGROUND: Revised international clinical guidelines for the antibiotic vancomycin have changed the advice pharmacists need to provide to medical and nursing colleagues. OBJECTIVES: (1) To determine the self-reported confidence of hospital pharmacists to provide contemporary advice on vancomycin and (2) to evaluate hospital pharmacists' knowledge to provide contemporary advice on vancomycin following a pilot continuing professional development (CPD) module. METHODS: The study was a prospective two-phase design in an Australian teaching hospital. Phase one: a survey of pharmacist self-reported confidence to eight questions on providing contemporary advice on vancomycin. Responses were recorded using a Likert scales. Phase two: The provision of a pilot online CPD module on vancomycin containing knowledge-based assessment based on a clinical vignette. Likert scales recorded self-reported confidence were reported as median and interquartile range (IQR). Knowledge assessment was reported using descriptive statistics. The main outcome measure were the self-reported confidence, and knowledge of pharmacists regarding provision of contemporary advice on clinical vancomycin use. RESULTS: Response rates for surveys; confidence n = 35 (72.9 %) and knowledge n = 31 (58.5 %). Phase one: confidence was highest regarding vancomycin dosing and monitoring with 71.4-81.6 % of respondents agreeing or strongly agreeing that they were confident in these domains. Respondents agreeing or strongly agreeing were least confident regarding intravenous administration and infusion related reactions, 57.1 and 45.7 % respectively. Respondents who provided advice on vancomycin >10 times in the prior 12 months reported significantly higher confidence in; therapeutic range 1 (IQR 1-2) versus 2 (IQR 1-3) p = 0.02; amending dosage based on therapeutic drug monitoring results 2 (IQR 1-3) versus 3 (IQR 2-3) p = 75 % of pharmacists. CONCLUSION: Pharmacists' self-reported confidence to managing vancomycin was variable but generally high. Knowledge scores were consistently high after pharmacists completed a pilot CPD module on vancomycin. These data provides impetus for a randomised controlled study across multiple sites to determine the extent to which pharmacist knowledge on vancomycin can be attributed to completion of an online CPD

    Health outcomes, healthcare use and development in children born into or growing up in single-parent households: a systematic review study protocol

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    INTRODUCTION: Up to a quarter of all children globally live in single-parent households. Studies have concluded that children who grow up with continuously married parents have better health outcomes than children who grow up with single or separated parents. This is consistent for key health and development outcomes including physical health, psychological well-being and educational attainment. Possible explanations include higher poverty and time limitations of parental engagement within single-parent families, but these only represent a narrow range of mechanisms. We aim to identify and synthesise the evidence on how being born into and/or living in a single-parent household compared with living in a two-parent household as a child impacts health and development outcomes, healthcare use and factors that may be driving differences. METHODS AND ANALYSIS: We will search PubMed, Scopus and ERIC and adapt our search terms for search engines and grey literature sites to include relevant conference abstracts and grey literature. We will restrict results to English language publications from 2000 to 2020 and screen against inclusion criteria. We will categorise main outcomes into five groups of outcomes: birth outcomes, mortality, physical health, mental health and development, and healthcare use. We will use the Newcastle-Ottawa Scale to assess the methodological quality of studies. Narrative synthesis will form the primary analysis in the review. Synthesis of effect estimates without meta-analysis will follow the Synthesis Without Meta-analysis guidelines. ETHICS AND DISSEMINATION: All documents used are publicly accessible. We will submit results to a peer-reviewed journal and international social science conferences. We will communicate results with single-parent groups and relevant charitable organisations. This review will also be included in IL's PhD thesis. PROSPERO REGISTRATION NUMBER: CRD42020197890

    Hardy-Weinberg and linkage equilibrium estimates in the BSSS and BSCB1 random mated populations

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    Because maize (Zea mays) is an annual species those working with it must frequently make crosses to preserve and periodically maintain populations. Random mating is performed either using hand-pollination techniques or in wind-pollinated isolated blocks. Eighty-two restriction fragment length polymorphism (RFLP) markers were used to examine samples of random mated, hand-pollinated BSSS(R) and BSCB1(R) maize populations to find out whether their genotypic proportions conformed to predicted outcomes of random mating. The majority of loci conformed to expectations for Hardy-Weinberg equilibrium (HWE). Excess homozygosity was observed at 87% of the loci where the null hypothesis of HWE was rejected. For pairs of polymorphic loci, linkage equilibrium was observed in the BSSS(R) and BSCB1(R) progenitor populations (fewer than 5% of all tests rejected the null hypothesis of equilibrium at the P≤0.05 significance level). The BSSS(R)CO, BSCB1(R)CO and BSCB1(R)C12 populations showed slight increases in the proportion of pairs of loci in linkage disequilibrium compared to the progenitors (approximately 8.4% of all pairs of loci rejected the null hypothesis at the P≤0.05 significance level). BSSS(R)C12 was an extreme outlier with 25.0% of all pairs of polymorphic loci displaying significant (P≤0.05) linkage disequilibrium. This result was likely caused by the artificial grouping of three BSSS(R)CO plants with 97 BSSS(R)C12 plants during sampling. Results from principal components analysis of all individuals based on RFLP alleles supported this interpretation. Overall, most of the observed deviations from equilibrium were likely to have been caused by positive assortative mating in the case of HWE, and natural selection for epistatic effects between unlinked loci in the case of linkage disequilibrium

    Population Genetics of Increased Hybrid Performance between Two Maize Populations under Reciprocal Recurrent Selection

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    Heterosis, the superiority in one or more characteristics of crossbred organisms relative to their inbred parents, is the basis of the modern cultivars utilized in maize (Zed mays L.). Heterosis is of interest in nondomesticated species due to its relevance to the question how much polymorphism is maintained in natural populations due to selection? (Berger, 1976). For maize and certain other domesticated species that employ inbred lines to produce commercial hybrids, knowledge of the mechanisms of gene action producing heterosis could contribute to advances in breeding techniques

    A Behaviour Change Analysis of Safer Sleep Interventions for Infants at Risk of Sudden and Unexpected Death

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    \ua9 2024 The Authors. Child Abuse Review published by Association of Child Protection Professionals and John Wiley & Sons Ltd.Rates of sudden unexpected death in infancy have been found to occur disproportionately amongst families living in the most deprived neighbourhoods. This suggests that standard safer sleep messaging may not be effective for this population and that research is required to identify ways of working that are better associated with behavioural change in parents with children at increased risk of SUDI. In this study, we aimed to explore the behavioural change components and mechanisms of action of safer sleep interventions for families with children at increased risk of SUDI. We conducted an analysis of the literature on safer sleep interventions using the COM-B model, Theoretical Domains Framework and Behavioural Change Technique Taxonomy. All interventions targeted parents\u27 capability; 15 interventions targeted parents\u27 opportunity; and six interventions targeted parents\u27 motivation to engage in safer sleep practices. Nineteen behavioural change techniques were identified. The focus of practitioners may need to shift from solely the delivery of safer sleep information towards working with parents to understand their capability, opportunity and, in particular, motivation to engage in safer sleep practices, identified as being a key driver of behaviour in this population
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