16,784 research outputs found

    Prevalence of substance use among rural high school students in Limpopo Province, South Africa

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    This study documents the prevalence rates for use of cigarette, alcohol, methylated spirit, cannabis, mandrax and cannabis together, glue or thinners among rural high school students in Mankweng, Limpopo Province, South Africa. A multistage sampling procedure produced a sample of 1600 students in grades 9 and 11 who completed a self-administered questionnaire. The prevalence rates for previous mouth (recent) use of alcohol, cigarettes, cannabis glue and spirits were 6.4%, 10.5%, 1.4%, 1.2% and 0,8% respectively. For all substances, males had higher prevalence rates than females. Developing alcohol and drug programme for high school students that are more gender specific may improve the effectiveness of intervention efforts at high schools. KEY WORDS: substance use, rural high school students, South Afric

    Regulation of ATP binding cassette transporter A1 (ABCA1) expression: cholesterol-dependent and - independent signaling pathways with relevance to inflammatory lung disease.

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    The role of the ATP binding cassette transporter A1 (ABCA1) in maintaining cellular lipid homeostasis in cardiovascular disease is well established. More recently, the important beneficial role played by ABCA1 in modulating pathogenic disease mechanisms, such as inflammation, in a broad range of chronic conditions has been realised. These studies position ABCA1 as a potential therapeutic target in a diverse range of diseases where inflammation is an underlying cause. Chronic respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD) are driven by inflammation, and as such, there is now a growing recognition that we need a greater understanding of the signaling pathways responsible for regulation of ABCA1 expression in this clinical context. While the signaling pathways responsible for cholesterol-mediated ABCA1 expression have been clearly delineated through decades of studies in the atherosclerosis field, and thus far appear to be translatable to the respiratory field, less is known about the cholesterol-independent signaling pathways that can modulate ABCA1 expression in inflammatory lung disease. This review will identify the various signaling pathways and ligands that are associated with the regulation of ABCA1 expression and may be exploited in future as therapeutic targets in the setting of chronic inflammatory lung diseases

    Interval State Estimation in Active Distribution Systems Considering Multiple Uncertainties.

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    Distribution system state estimation (DSSE) plays a significant role for the system operation management and control. Due to the multiple uncertainties caused by the non-Gaussian measurement noise, inaccurate line parameters, stochastic power outputs of distributed generations (DG), and plug-in electric vehicles (EV) in distribution systems, the existing interval state estimation (ISE) approaches for DSSE provide fairly conservative estimation results. In this paper, a new ISE model is proposed for distribution systems where the multiple uncertainties mentioned above are well considered and accurately established. Moreover, a modified Krawczyk-operator (MKO) in conjunction with interval constraint-propagation (ICP) algorithm is proposed to solve the ISE problem and efficiently provides better estimation results with less conservativeness. Simulation results carried out on the IEEE 33-bus, 69-bus, and 123-bus distribution systems show that the our proposed algorithm can provide tighter upper and lower bounds of state estimation results than the existing approaches such as the ICP, Krawczyk-Moore ICP(KM-ICP), Hansen, and MKO

    The effect of statins and the synthetic LXR agonist T0901317 on expression of ABCA1 transporter protein in human lung epithelial cell lines in vitro

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    © 2019 Institute of Pharmacology, Polish Academy of Sciences Background: The pathogenesis of chronic obstructive pulmonary disease (COPD) is associated with dyslipidemia, an established co-morbidity. Statins treat hypercholesterolemia, but more recently have been trailed in the setting of COPD for their potential anti-inflammatory benefits. The outcomes of prospective trials however have been inconsistent. Thus, we hypothesize that the variation in results may have been due to statin-induced downregulation of ATP-binding cassette transporter A1 (ABCA1), thereby reducing cholesterol export. This study aims to elucidate whether statin treatment in a cellular model of COPD leads to a decrease in ABCA1 protein expression. Methods: To mimic the inflammatory environment of COPD, two commonly used lung epithelial cell lines (BEAS-2B and A549) were treated with tumor necrosis factor (TNF), and co-treated with cholesterol/25-hydroxycholesterol (25-OH) to mimic dyslipidemia. ABCA1 protein was detected by Western Blotting. Results: We unexpectedly showed that statins did not affect ABCA1 expression. However, the LXR agonist T0901317 significantly increased ABCA1 expression in both cell lines, while TNF, cholesterol or 25-OH induced ABCA1 protein upregulation in BEAS-2B cells, indicating cell line differences in response. There was also evidence of synergistic impacts of combined treatments on ABCA1 upregulation in BEAS-2B cells. Conclusion: Statins did not have an impact on ABCA1 expression in lung epithelial cell lines, disproving our original hypothesis. However, we showed for the first time, the effect of the inflammatory cytokine TNF, cholesterol/25-OH, statins and the LXR agonist T0901317 on expression of ABCA1 transporter protein in human lung epithelial cell lines in vitro. We hope that these in vitro studies may prove beneficial for addressing dyslipidemia in COPD in the future

    Physical cleaning techniques to control fouling during the pre-concentration of high suspended-solid content solutions for resource recovery by forward osmosis

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    © 2017 The fouling propensity of digested sludge centrate, and the effectiveness of membrane flushing, air-scouring, and ultrasonication for physical cleaning were systematically evaluated. Accelerated fouling conditions were applied to simulate the long-term and intensive pre-concentration scenario that is required for phosphorus recovery from digested sludge centrate. The results suggest that membrane fouling during forward osmosis operation to pre-concentrate digested sludge centrate is mostly due to the deposition of small mineral crystals and particulate matter on the membrane surface. Both high cross-flow velocity flushing and ultrasonication were effective at preventing membrane fouling under accelerated fouling conditions. Our results also highlight the potential of intermittent membrane cleaning for achieving a higher cumulative permeate volume and lower energy consumption in comparison to continuous application to prevent membrane fouling. Among several physical cleaning regimes investigated in this study, the combination of ultrasonication and high cross-flow velocity flushing was the most effective and could maintain stable FO operation over several consecutive cleaning cycles

    Family-based interventions to increase physical activity in children: a systematic review, meta-analysis and realist synthesis.

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    OBJECTIVE: Family-based interventions represent a potentially valuable route to increasing child physical activity (PA) in children. A dual meta-analysis and realist synthesis approach examined existing interventions to assist those developing programmes to encourage uptake and maintenance of PA in children. DESIGN: Studies were screened for inclusion based on including participants aged 5-12 years, having a substantive aim of increasing PA by engaging the family and reporting on PA outcome. Duplicate data extraction and quality assessment were conducted. Meta-analysis was conducted in STATA. Realist synthesis included theory development and evidence mapping. RESULTS: Forty-seven studies were included, of which three received a 'strong' quality rating, 21 'moderate' and 23 'weak'. The meta-analysis (19 studies) demonstrated a significant small effect in favour of the experimental group (standardized mean difference: 0.41; 95%CI 0.15-0.67). Sensitivity analysis, removing one outlier, reduced this to 0.29 (95%CI 0.14-0.45). Realist synthesis (28 studies) provided insight into intervention context (particularly, family constraints, ethnicity and parental motivation), and strategies to change PA (notably, goal-setting and reinforcement combined). CONCLUSION: This review provides key recommendations to inform policy makers and other practitioners in developing evidence-based interventions aimed at engaging the family to increase PA in children, and identifies avenues for future research.This research received no specific grant from any funding agency in the public, commercial or not-for- profit sectors. This work was supported by the Medical Research Council [Unit Programme number: MC_UU_12015/7], and undertaken under the auspices of the Centre for Diet and Activity Research, a UKCRC Public Health Research Centre of Excellence which is funded by the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, the National Institute for Health Research, and the Wellcome Trust (RES-590-28-0002). JP is supported by an NIHR post-doctoral fellowship (NIHR-PDF-2012-05-157). This article presents independent research in which the funders had no involvement in the study design; the collection, analysis, and interpretation of data; the writing of the article; or the decision to submit the article for publication. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR, the Department of Health or the other funders.This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1111/obr.1236

    Dog owners are more likely to meet physical activity guidelines than people without at dog: An investigation of the association between dog ownership and physical activity levels in a UK community

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    Previous research suggests that dog owners are slightly more physically active than those without dogs, but have only studied one household member, and it is unclear whether time spent dog walking replaces other physical activity (PA). A survey of 191 dog owning adults (DO), 455 non-dog owning adults (NDO), and 46 children, living in 385 households in West Cheshire UK, was conducted in July-August 2015. Objective (accelerometer) validation occurred on a subset (n=28 adults). Survey PA outcomes were modelled using hierarchical logistic and linear multivariable regression modelling, accounting for clustering of participants in households. DO were far more likely than NDO to report walking for recreation (OR=14.35, 95% CI=5.77-35.79, P<0.001), and amongst recreational walkers walked for longer per week (RR=1.39, 95%CI=1.27-5.91, P<0.001). Other PA undertaken did not differ by dog ownership. The odds of DO meeting current physical activity guidelines of 150mins per week were four times greater than for NDO (OR=4.10, 95% CI=2.05-8.19, P<0.001). Children with dogs reported more minutes of walking (P=0.01) and free-time (unstructured) activity (P<0.01). Dog ownership is associated with more recreational walking and considerably greater odds of meeting PA guidelines. Policies regarding public spaces and housing should support dog ownership due to PA benefits

    How wasting is saving: Weight loss at altitude might result from an evolutionary adaptation

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    At extreme altitude (>5,000 – 5,500 m), sustained hypoxia threatens human function and survival, and is associated with marked involuntary weight loss (cachexia). This seems to be a coordinated response: appetite and protein synthesis are suppressed, and muscle catabolism promoted. We hypothesise that, rather than simply being pathophysiological dysregulation, this cachexia is protective. Ketone bodies, synthesised during relative starvation, protect tissues such as the brain from reduced oxygen availability by mechanisms including the reduced generation of reactive oxygen species, improved mitochondrial efficiency and activation of the ATP-sensitive potassium (KATP) channel. Amino acids released from skeletal muscle also protect cells from hypoxia, and may interact synergistically with ketones to offer added protection. We thus propose that weight loss in hypoxia is an adaptive response: the amino acids and ketone bodies made available act not only as metabolic substrates, but as metabolic modulators, protecting cells from the hypoxic challenge

    Recent Advances in Ultralow-Pt-Loading Electrocatalysts for the Efficient Hydrogen Evolution.

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    Hydrogen production from water electrolysis provides a green and sustainable route. Platinum (Pt)-based materials have been regarded as efficient electrocatalysts for the hydrogen evolution reaction (HER). However, the large-scale commercialization of Pt-based catalysts suffers from the high cost. Therefore, ultralow-Pt-loading electrocatalysts, which can reach the balance of low cost and high HER performance, have attracted much attention. In this review, representative promising synthetic strategies, including wet chemistry, annealing, electrochemistry, photochemistry, and atomic layer deposition are summarized. Further, the interaction between different electrocatalyst components (transition metals and their derivatives) and Pt is discussed. Notably, this interaction can effectively accelerate the kinetics of the HER, enhancing the catalytic activity. At last, current challenges and future perspectives are briefly discussed
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