2,131 research outputs found

    Eta carinae and the homunculus: far infrared/submillimetre spectral lines detected with the Herschel Space Observatory

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    The evolved massive binary star η Carinae underwent eruptive mass-loss events that formed the complex bi-polar ‘Homunculus’ nebula harbouring tens of solar masses of unusually nitrogen-rich gas and dust. Despite expectations for the presence of a significant molecular component to the gas, detections have been observationally challenged by limited access to the far-infrared and the intense thermal continuum. A spectral survey of the atomic and rotational molecular transitions was carried out with the Herschel Space Observatory, revealing a rich spectrum of broad emission lines originating in the ejecta. Velocity profiles of selected PACS lines correlate well with known substructures: H I in the central core; NH and weak [C II] within the Homunculus; and [N II] emissions in fast-moving structures external to the Homunculus. We have identified transitions from [O I], H I, and 18 separate light C- and O-bearing molecules including CO, CH, CH+, and OH, and a wide set of N-bearing molecules: NH, NH+, N2H+, NH2, NH3, HCN, HNC, CN, and N2H+. Half of these are new detections unprecedented for any early-type massive star environment. A very low ratio [12C/13C] ≤ 4 is estimated from five molecules and their isotopologues. We demonstrate that non-LTE effects due to the strong continuum are significant. Abundance patterns are consistent with line formation in regions of carbon and oxygen depletions with nitrogen enhancements, reflecting an evolved state of the erupting star with efficient transport of CNO-processed material to the outer layers. The results offer many opportunities for further observational and theoretical investigations of the molecular chemistry under extreme physical and chemical conditions around massive stars in their final stages of evolution

    Using Electronic Technology to Improve Clinical Care -- Results from a Before-after Cluster Trial to Evaluate Assessment and Classification of Sick Children According to Integrated Management of Childhood Illness (IMCI) Protocol in Tanzania.

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    Poor adherence to the Integrated Management of Childhood Illness (IMCI) protocol reduces the potential impact on under-five morbidity and mortality. Electronic technology could improve adherence; however there are few studies demonstrating the benefits of such technology in a resource-poor settings. This study estimates the impact of electronic technology on adherence to the IMCI protocols as compared to the current paper-based protocols in Tanzania. In four districts in Tanzania, 18 clinics were randomly selected for inclusion. At each site, observers documented critical parts of the clinical assessment of children aged 2 months to 5 years. The first set of observations occurred during examination of children using paper-based IMCI (pIMCI) and the next set of observations occurred during examination using the electronic IMCI (eIMCI). Children were re-examined by an IMCI expert and the diagnoses were compared. A total of 1221 children (671 paper, 550 electronic) were observed. For all ten critical IMCI items included in both systems, adherence to the protocol was greater for eIMCI than for pIMCI. The proportion assessed under pIMCI ranged from 61% to 98% compared to 92% to 100% under eIMCI (p < 0.05 for each of the ten assessment items). Use of electronic systems improved the completeness of assessment of children with acute illness in Tanzania. With the before-after nature of the design, potential for temporal confounding is the primary limitation. However, the data collection for both phases occurred over a short period (one month) and so temporal confounding was expected to be minimal. The results suggest that the use of electronic IMCI protocols can improve the completeness and consistency of clinical assessments and future studies will examine the long-term health and health systems impact of eIMCI

    Contrasting environmental drivers of adult and juvenile growth in a marine fish: implications for the effects of climate change

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    Many marine fishes have life history strategies that involve ontogenetic changes in the use of coastal habitats. Such ontogenetic shifts may place these species at particular risk from climate change, because the successive environments they inhabit can differ in the type, frequency and severity of changes related to global warming. We used a dendrochronology approach to examine the physical and biological drivers of growth of adult and juvenile mangrove jack (Lutjanus argentimaculatus) from tropical north-western Australia. Juveniles of this species inhabit estuarine environments and adults reside on coastal reefs. The Niño-4 index, a measure of the status of the El Niño-Southern Oscillation (ENSO) had the highest correlation with adult growth chronologies, with La Niña years (characterised by warmer temperatures and lower salinities) having positive impacts on growth. Atmospheric and oceanographic phenomena operating at ocean-basin scales seem to be important correlates of the processes driving growth in local coastal habitats. Conversely, terrestrial factors influencing precipitation and river runoff were positively correlated with the growth of juveniles in estuaries. Our results show that the impacts of climate change on these two life history stages are likely to be different, with implications for resilience and management of populations

    Fractal Profit Landscape of the Stock Market

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    We investigate the structure of the profit landscape obtained from the most basic, fluctuation based, trading strategy applied for the daily stock price data. The strategy is parameterized by only two variables, p and q. Stocks are sold and bought if the log return is bigger than p and less than -q, respectively. Repetition of this simple strategy for a long time gives the profit defined in the underlying two-dimensional parameter space of p and q. It is revealed that the local maxima in the profit landscape are spread in the form of a fractal structure. The fractal structure implies that successful strategies are not localized to any region of the profit landscape and are neither spaced evenly throughout the profit landscape, which makes the optimization notoriously hard and hypersensitive for partial or limited information. The concrete implication of this property is demonstrated by showing that optimization of one stock for future values or other stocks renders worse profit than a strategy that ignores fluctuations, i.e., a long-term buy-and-hold strategy.Comment: 12 pages, 4 figure

    Conformational effects on the Circular Dichroism of Human Carbonic Anhydrase II: a multilevel computational study

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    Circular Dichroism (CD) spectroscopy is a powerful method for investigating conformational changes in proteins and therefore has numerous applications in structural and molecular biology. Here a computational investigation of the CD spectrum of the Human Carbonic Anhydrase II (HCAII), with main focus on the near-UV CD spectra of the wild-type enzyme and it seven tryptophan mutant forms, is presented and compared to experimental studies. Multilevel computational methods (Molecular Dynamics, Semiempirical Quantum Mechanics, Time-Dependent Density Functional Theory) were applied in order to gain insight into the mechanisms of interaction between the aromatic chromophores within the protein environment and understand how the conformational flexibility of the protein influences these mechanisms. The analysis suggests that combining CD semi empirical calculations, crystal structures and molecular dynamics (MD) could help in achieving a better agreement between the computed and experimental protein spectra and provide some unique insight into the dynamic nature of the mechanisms of chromophore interactions

    Improving the management of pain from advanced cancer in the community: study protocol for a pragmatic multi-centre randomised controlled trial

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    Introduction: For patients with advanced cancer, research shows that pain is frequent, burdensome and undertreated. Evidence-based approaches to support cancer pain management have been developed but have not been implemented within the context of the UK National Health Service. This protocol is for a pragmatic multi-centre randomised controlled trial to assess feasibility, acceptability, effectiveness and cost effectiveness for a multi-component intervention for pain management in patients with advanced cancer. Methods and Analysis: This trial will assess the feasibility of implementation and uptake of evidence based interventions, developed and piloted as part of the IMPACCT Programme grant, into routine clinical practice and determine whether there are potential differences with respect to patient rated pain, patient pain knowledge and experience, healthcare use, quality of life, and cost effectiveness. 160 patients will receive either the intervention (usual care plus supported self-management) delivered within the oncology clinic and palliative care services by locally assigned community palliative care nurses, consisting of a self-management educational intervention and eHealth intervention for routine pain assessment and monitoring; or usual care. The primary outcomes are to assess implementation and uptake of the interventions, and differences in terms of pain severity. Secondary outcomes include pain interference, participant pain knowledge and experience, and cost effectiveness. Outcome assessment will be blinded and patient reported outcome measures collected via post at 6 and 12 weeks following randomisation. Ethics and Dissemination: This RCT has the potential to significantly influence NHS service delivery to community based patients with pain from advanced cancer. We aim to provide definitive evidence of whether two simple interventions delivered by community palliative care nurse in palliative care that support-self-management are clinically and cost effective additions to standard community palliative care

    The politics of regulatory enforcement and compliance: Theorizing and operationalizing political influences

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    There is broad consensus in the literature on regulatory enforcement and compliance that politics matters. However, there is little scholarly convergence on what politics is or rigorous theorization and empirical testing of how politics matters. Many enforcement and compliance studies omit political variables altogether. Among those that address political influences on regulatory outcomes, politics has been defined in myriad ways and, too often, left undefined. Even when political constructs are explicitly operationalized, the mechanisms by which they influence regulatory outcomes are thinly hypothesized or simply ignored. If politics is truly as important to enforcement and compliance outcomes as everyone in the field seems to agree, regulatory scholarship must make a more sustained and systematic effort to understand their relationship, because overlooking this connection risks missing what is actually driving regulatory outcomes. This article examines how the construct of “politics” has been conceptualized in regulatory theory and analyzes how it has been operationalized in empirical studies of regulatory enforcement and compliance outcomes. It brings together scholarship across disciplines that rarely speak but have much to say to one another on this subject in order to constitute a field around the politics of regulation. The goal is to sharpen theoretical and empirical understandings of when and how regulation works by better accounting for the role politics plays in its enforcement

    What is regulation? An interdisciplinary concept analysis

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    The concept of regulation is believed to suffer from a lack of shared understanding. Yet, the maturation of the field raises the question whether this conclusion is still valid. By taking a new methodological approach towards this question of conceptual consolidation, this study assesses how regulation is conceived in the most-cited articles in six social science disciplines. Four main conclusions are drawn. First, there is a remarkable absence of explicit definitions. Second, the scope of the concept is vast, which requires us to talk about regulation in rather abstract terms. Third, scholars largely agree that ‘prototype regulation’ is characterised by interventions which are intentional and direct – involving binding standard-setting, monitoring and sanctioning – and exercised by public-sector actors on the economic activities of private-sector actors. Fourth, while there is considerable variation in research concerns, this variation cannot be attributed to disciplinary differences. Instead, our findings support the portrayal of the field as interdisciplinary, including a shared conception of regulation

    Patient-reported outcome measures for asthma:a systematic review

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    BACKGROUND: Patient-reported outcome measures (PROMs) are measures of the outcome of treatment(s) reported directly by the patient or carer. There is increasing international policy interest in using these to assess the impact of clinical care. AIMS: To identify suitably validated PROMs for asthma and examine their potential for use in clinical settings. METHODS: We systematically searched MEDLINE, EMBASE and Web of Science databases from 1990 onwards to identify PROMs for asthma. These were critically appraised, then narratively synthesised. We also identified the generic PROMs commonly used alongside asthma-specific PROMs. RESULTS: We identifi ed 68 PROMs for asthma, 13 of which were selected through screening as being adequately developed to warrant full-quality appraisal: 8 for adults, 4 for children and 1 for a child's caregiver. The PROMs found to be sufficiently well validated to offer promise for use in clinical settings were the Asthma Quality of Life Questionnaire (AQLQ) and mini-AQLQ for adults, and Pediatric Asthma Quality of Life Questionnaire for children. Rhinasthma was considered promising in simultaneously assessing the impact of asthma and rhinitis in those with coexistent disease. We identified 28 generic PROMs commonly used in conjunction with asthma-specific instruments. CONCLUSIONS: We identified asthma PROMs that offer the greatest potential for use in clinical settings. Further work is needed to assess whether these are fit-for-purpose for use in clinical practice with individual patients. In particular, there is a need to ensure these are validated for use in clinical settings, acceptable to patients, caregivers and clinicians, and yield meaningful outcomes. © 2014 Primary Care Respiratory Society/Macmillan Publishers Limited

    Effectiveness of bisphosphonates on nonvertebral and hip fractures in the first year of therapy: The risedronate and alendronate (REAL) cohort study

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    INTRODUCTION: Randomized clinical trials have shown that risedronate and alendronate reduce fractures among women with osteoporosis. The aim of this observational study was to observe, in clinical practice, the incidence of hip and nonvertebral fractures among women in the year following initiation of once-a-week dosing of either risedronate or alendronate. METHODS: Using records of health service utilization from July 2002 through September 2004, we created two cohorts: women (ages 65 and over) receiving risedronate (n = 12,215) or alendronate (n = 21,615). Cox proportional hazard modeling was used to compare the annual incidence of nonvertebral fractures and of hip fractures between cohorts, adjusting for potential differences in risk factors for fractures. RESULTS: There were 507 nonvertebral fractures and 109 hip fractures. Through one year of therapy, the incidence of nonvertebral fractures in the risedronate cohort (2.0%) was 18% lower (95% CI 2% – 32%) than in the alendronate cohort (2.3%). The incidence of hip fractures in the risedronate cohort (0.4%) was 43% lower (95% CI 13% – 63%) than in the alendronate cohort (0.6%). These results were consistent across a number of sensitivity analyses. CONCLUSION: Patients receiving risedronate have lower rates of hip and nonvertebral fractures during their first year of therapy than patients receiving alendronate
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