816 research outputs found

    Correspondence between environmental gradients and summer littoral fish assemblages in low salinity reaches of the Chesapeake Bay, USA

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    Patterns in the assemblage structure of littoral fishes occupying the gradient between riverine and estuarine ecosystems were revealed through multivariate analysis of 5 annual summer seine surveys in 4 tributary systems of the lower Chesapeake Bay. Catch per unit effort of fishes was quantified and environmental variables measured to characterize assemblage structure and population responses along large-scale (km) environmental gradients. Results of two-way indicator species analysis (TWINSPAN), detrended correspondence analysis (DCA) and detrended canonical correspondence analysis (DCCA) suggested the presence of 4 intergrading assemblages of littoral beach fishes: permanent tidal freshwater, lower tidal freshwater, oligohaline estuary and mesohaline estuary. Littoral fish assemblages were ordered along a large-scale spatial gradient between tidal freshwater and mesohaline river reaches during summer, when relatively stable hydrological conditions create a well-defined salinity gradient. Large-scale distribution of these fishes along the liver axis corresponded with salinity (and its correlates) up to the interface, and with structural attributes of the habitat (nearshore sediment grain size, presence of submerged aquatic vegetation, woody debris) in the permanent tidal freshwater river reaches. The permanent tidal freshwater reaches were more riverine in character, and were typified by speciose and relatively stable assemblages dominated by resident secondary division freshwater fishes and the juveniles of several diadromous species. Although the resident fauna is certainly derivative of more upland, non-tidal streams. patterns of association suggest distinct ecological relationships may exist for species co-occurring in tidal freshwater habitats

    Thin films of a dimeric ruthenium phthalocyanine complex on gold

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    Thin films of a new dimeric ruthenium phthalocyanine complex bearing a thioester-functionalized axial ligand were formed on gold surfaces. Characterization of the thin films by laser ablation-inductively coupled-mass spectrometry and scanning tunneling microscopy revealed that the films do not have any long-range order. © 2009 Elsevier B.V. All rights reserved

    Thin films of Ruthenium Phthalocyanine complexes

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    Four new ruthenium phthalocyanine complexes bearing axial ligands with thioacetate groups that facilitate thin film formation on gold surfaces are presented. Scanning tunnelling microscopy (STM) images and surface coverage data obtained by solution inductively coupled plasma mass spectrometry (ICP-MS) experiments show that peripheral and axial ligand substituents on the complexes have a significant effect on their surface coverage. A laser ablation ICP-MS technique that provides information about thin films across macro-sized areas is described here for the first time. Using the technique, the maximum surface coverage of a ruthenium phthalocyanine complex was found to occur within one minute of gold substrate immersion in the complexcontaining solution

    Effects of air pollution and the introduction of the London Low Emission Zone on the prevalence of respiratory and allergic symptoms in schoolchildren in East London: a sequential cross-sectional study

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    The adverse effects of traffic-related air pollution on children’s respiratory health have been widely reported, but few studies have evaluated the impact of traffic-control policies designed to reduce urban air pollution. We assessed associations between traffic-related air pollutants and respiratory/allergic symptoms amongst 8–9 year-old schoolchildren living within the London Low Emission Zone (LEZ). Information on respiratory/allergic symptoms was obtained using a parent-completed questionnaire and linked to modelled annual air pollutant concentrations based on the residential address of each child, using a multivariable mixed effects logistic regression analysis. Exposure to traffic-related air pollutants was associated with current rhinitis: NOx (OR 1.01, 95% CI 1.00–1.02), NO2 (1.03, 1.00–1.06), PM10 (1.16, 1.04–1.28) and PM2.5 (1.38, 1.08–1.78), all per μg/m3 of pollutant, but not with other respiratory/allergic symptoms. The LEZ did not reduce ambient air pollution levels, or affect the prevalence of respiratory/allergic symptoms over the period studied. These data confirm the previous association between traffic-related air pollutant exposures and symptoms of current rhinitis. Importantly, the London LEZ has not significantly improved air quality within the city, or the respiratory health of the resident population in its first three years of operation. This highlights the need for more robust measures to reduce traffic emissions

    Rehabilitation Enablement in Chronic Heart Failure—a facilitated self-care rehabilitation intervention in patients with heart failure with preserved ejection fraction (REACH-HFpEF) and their caregivers:rationale and protocol for a single-centre pilot randomised controlled trial

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    This is the final version of the article. Available from the publisher via the DOI in this record.INTRODUCTION: The Rehabilitation EnAblement in CHronic Heart Failure in patients with Heart Failure (HF) with preserved ejection fraction (REACH-HFpEF) pilot trial is part of a research programme designed to develop and evaluate a facilitated, home-based, self-help rehabilitation intervention to improve self-care and quality of life (QoL) in heart failure patients and their caregivers. We will assess the feasibility of a definitive trial of the REACH-HF intervention in patients with HFpEF and their caregivers. The impact of the REACH-HF intervention on echocardiographic outcomes and bloodborne biomarkers will also be assessed. METHODS AND ANALYSIS: A single-centre parallel two-group randomised controlled trial (RCT) with 1:1 individual allocation to the REACH-HF intervention plus usual care (intervention) or usual care alone (control) in 50 HFpEF patients and their caregivers. The REACH-HF intervention comprises a REACH-HF manual with supplementary tools, delivered by trained facilitators over 12 weeks. A mixed methods approach will be used to assess estimation of recruitment and retention rates; fidelity of REACH-HF manual delivery; identification of barriers to participation and adherence to the intervention and study protocol; feasibility of data collection and outcome burden. We will assess the variance in study outcomes to inform a definitive study sample size and assess methods for the collection of resource use and intervention delivery cost data to develop the cost-effectiveness analyses framework for any future trial. Patient outcomes collected at baseline, 4 and 6 months include QoL, psychological well-being, exercise capacity, physical activity and HF-related hospitalisation. Caregiver outcomes will also be assessed, and a substudy will evaluate impact of the REACH-HF manual on resting global cardiovascular function and bloodborne biomarkers in HFpEF patients. ETHICS AND DISSEMINATION: The study is approved by the East of Scotland Research Ethics Service (Ref: 15/ES/0036). Findings will be disseminated via journals and presentations to clinicians, commissioners and service users. TRIAL REGISTRATION NUMBER: ISRCTN78539530; Pre-results .This paper presents independent research funded by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research Programme (Grant Reference Number RP-PG-1210-12004). NB, CA, CJG and RST are also supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care (CLAHRC) South West Peninsula at the Royal Devon and Exeter NHS Foundation Trust; KJ by CLAHRC West Midlands and SS by CLAHRC East-Midlands. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Healt

    Dietary Supplementation with Soluble Plantain Non-Starch Polysaccharides Inhibits Intestinal Invasion of Salmonella Typhimurium in the Chicken

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    Soluble fibres (non-starch polysaccharides, NSP) from edible plants but particularly plantain banana (Musa spp.), have been shown in vitro and ex vivo to prevent various enteric pathogens from adhering to, or translocating across, the human intestinal epithelium, a property that we have termed contrabiotic. Here we report that dietary plantain fibre prevents invasion of the chicken intestinal mucosa by Salmonella. In vivo experiments were performed with chicks fed from hatch on a pellet diet containing soluble plantain NSP (0 to 200 mg/d) and orally infected with S.Typhimurium 4/74 at 8 d of age. Birds were sacrificed 3, 6 and 10 d post-infection. Bacteria were enumerated from liver, spleen and caecal contents. In vitro studies were performed using chicken caecal crypts and porcine intestinal epithelial cells infected with Salmonella enterica serovars following pre-treatment separately with soluble plantain NSP and acidic or neutral polysaccharide fractions of plantain NSP, each compared with saline vehicle. Bacterial adherence and invasion were assessed by gentamicin protection assay. In vivo dietary supplementation with plantain NSP 50 mg/d reduced invasion by S.Typhimurium, as reflected by viable bacterial counts from splenic tissue, by 98.9% (95% CI, 98.1–99.7; P<0.0001). In vitro studies confirmed that plantain NSP (5–10 mg/ml) inhibited adhesion of S.Typhimurium 4/74 to a porcine epithelial cell-line (73% mean inhibition (95% CI, 64–81); P<0.001) and to primary chick caecal crypts (82% mean inhibition (95% CI, 75–90); P<0.001). Adherence inhibition was shown to be mediated via an effect on the epithelial cells and Ussing chamber experiments with ex-vivo human ileal mucosa showed that this effect was associated with increased short circuit current but no change in electrical resistance. The inhibitory activity of plantain NSP lay mainly within the acidic/pectic (homogalacturonan-rich) component. Supplementation of chick feed with plantain NSP was well tolerated and shows promise as a simple approach for reducing invasive salmonellosis

    Informing the design of a national screening and treatment programme for chronic viral hepatitis in primary care: qualitative study of at-risk immigrant communities and healthcare professionals

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    n Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise statedThis paper presents independent research funded by the National Institute for Health Research (NIHR) under the Programme Grants for Applied Research programme (RP-PG-1209-10038).

    Insulin versus oral agents in the management of Cystic Fibrosis Related Diabetes: a case based study

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    BACKGROUND: Insulin is the recommend therapeutic agent of choice for the management of Cystic Fibrosis Related Diabetes (CFRD), despite only sub-optimal reductions in glycemic control and increased morbidity and mortality reported by centers using this agent. The newer insulin sensitizing agents demonstrated to have anti-inflammatory mechanisms may provide an alternative management option for CFRD. METHODS: A prospective case based therapeutic comparison between insulin, sulfonylurea, metformin and thiazolidinedione was observed over one decade with 20 CFRD patients diagnosed using American Diabetes Association guideline standards. Patients entering the study elected treatment based on risk and benefit information provided for treatment options. Patients receiving organ transplant or requiring combination diabetic medications were excluded from the study. RESULTS: No statistical advantage was achieved regarding overall glycemic control for oral agents over insulin. Additional outcome measures including changes in weight, liver function testing and FEV(1 )were not statistically significant. CONCLUSION: Insulin alone may not be the only therapeutic option in managing CFRD. Oral hypoglycemic agents were equally effective in treating CFRD and may provide an alternative class of agents for patients reluctant in using insulin

    Breast feeding and intergenerational social mobility: what are the mechanisms?

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    Objective To investigate the association between breast feeding and intergenerational social mobility and the possible mediating role of neurological and stress mechanisms. Design Secondary analysis of data from the 1958 and the 1970 British Cohort Studies. Setting Longitudinal study of individuals born in Britain during 1 week in 1958 and 1970. Participants 17 419 individuals participated in the 1958 cohort and 16 771 in the 1970 cohort. The effect of breast feeding on intergenerational social mobility from age 10/11 to age 33/34 was analysed after multiple imputations to fill in missing data and propensity score matching on a wide range of confounders measured in childhood (1958 cohort N=16 039-16 154; 1970 cohort N=16 255-16 361). Main outcome measures Own Registrar General's Social Class (RGSC) at 33/34 years adjusted for father's RGSC at 10/11 years, gender and their interaction. Results Breastfed individuals were more likely to be upwardly mobile (1958 cohort: OR 1.24 95% CI 1.12 to 1.38; 1970 cohort: OR 1.24 95% CI 1.12 to 1.37) and less likely to be downwardly mobile (1958 cohort: OR 0.81 95% CI 0.73 to 0.90; 1970 cohort: OR 0.79 95% CI 0.71 to 0.88). In an ordinal regression model, markers of neurological development (cognitive test scores) and stress (emotional stress scores) accounted for approximately 36% of the relationship between breast feeding and social mobility. Conclusions Breast feeding increased the odds of upward social mobility and decreased the odds of downward mobility. Consistent with a causal explanation, the findings were robust to matching on a large number of observable variables and effect sizes were alike for two cohorts with different social distributions of breast feeding. The effect was mediated in part through neurological and stress mechanisms

    Mark Carney and the gendered political economy of British central banking

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    In this article we explore Mark Carney’s place in the gendered political economy of British central banking. We document the gendered narratives surrounding Carney around the time of his appointment as Governor of the Bank of England, suggesting that they worked to naturalise certain gender constructions in finance. We show how Carney seemingly had the ability to successfully embody a combination of two ideal-types of masculinity: both ‘transnational business masculinity’ and ‘traditional bourgeois masculinity’. We argue this contributed to three depoliticising moves, each of which gain their strength in part from the naturalisation of masculinities in finance, while obfuscating important questions of gendered finance. To elucidate the latter, we highlight some of the gendered outcomes that are obscured by the furore surrounding Carney’s character, suggesting that the monetary and financial stability concerns of the Bank under his stewardship are likely to reproduce the uneven and exploitative relations of gendered finance
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