1,229 research outputs found

    An overview of Cu-based heterogeneous electrocatalysts for CO2 reduction

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    The electrochemical (EC) reduction of CO2 is a promising approach for value-added fuel or chemical production. Cu-based electrodes have been extensively used as a ‘star’ material for CO2 reduction to hydrocarbons. This review mainly focuses on the recent progress of Cu-based heterogeneous electrocatalysts for CO2 reduction from 2013 to 2019. Various morphologies of oxide-derived, bimetallic Cu species and their activity in EC CO2 reduction are reviewed, providing insights for the standardization of Cu-based heterogeneous systems. We also present a tutorial manual to describe parameters for the EC CO2 reduction process, especially for the pretreatment of the reaction system. This will offer useful guidance for newcomers to the field. Aqueous and non-aqueous electrolyte effects based on Cu electrodes are discussed. Finally, an overview of reaction systems of EC/PEC CO2 reduction and H2O oxidation for Cu-based heterogeneous catalysts is provided

    Clinical Benefits Associated With Medicaid Coverage Before Diagnosis of Gynecologic Cancers

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    Many low-income patients enroll in Medicaid at the time of cancer diagnosis, which improves survival outcomes. Medicaid enrollment before cancer diagnosis may confer additional benefits. Our objective was to compare stage at diagnosis and overall mortality between women with and without Medicaid enrollment before gynecologic cancer diagnosis

    On the two-dimensional solution of both adhesive and non-adhesive contact problems involving functionally graded materials

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    This paper presents a semi-analytical algorithm for the determination of the contact half width and surface pressure which results from both adhesive and non-adhesive contact problems involving functionally graded materials (FGM). The inhomogeneously elastic solid comprises a graded elastic coating whose shear modulus depends exponentially on the vertical coordinate and a homogeneously elastic substrate. The solid is assumed to be in a state of plane strain and thus a two-dimensional analysis is performed within this work. Using the work of Chidlow et al. (2011a) as a starting point, we derive a pair of integral equations which may be used to determine approximations to the contact pressure when either the surface deflection or the deflection gradient is known over the contact region. As these integral equations are non-singular, we use Galerkin's method to approximate the contact pressure and it is found that relatively small trial spaces allow accurate computation of the pressure. Information about the prescribed load is then used to formulate an iterative algorithm to determine the contact half width. A selection of numerical results are presented using this method and it is found that the solutions computed here compare favourably with those of other authors. A further investigation is then conducted into the solution of adhesive contact problems using the assumptions of Maugis (1992) and Johnson and Greenwood (2008) to inform the nature of the adhesive stresses outside of the contact. It is found that both JKR-like and DMT-like behaviour can be observed in contact problems involving FGMs

    Growing up in Bradford: protocol for the age 7-11 follow up of the Born in Bradford birth cohort.

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    BACKGROUND: Born in Bradford (BiB) is a prospective multi-ethnic pregnancy and birth cohort study that was established to examine determinants of health and development during childhood and, subsequently, adult life in a deprived multi-ethnic population in the north of England. Between 2007 and 2010, the BiB cohort recruited 12,453 women who experienced 13,776 pregnancies and 13,858 births, along with 3353 of their partners. Forty five percent of the cohort are of Pakistani origin. Now that children are at primary school, the first full follow-up of the cohort is taking place. The aims of the follow-up are to investigate the determinants of children's pre-pubertal health and development, including through understanding parents' health and wellbeing, and to obtain data on exposures in childhood that might influence future health. METHODS: We are employing a multi-method approach across three data collection arms (community-based family visits, school based physical assessment, and whole classroom cognitive, motor function and wellbeing measures) to follow-up over 9000 BiB children aged 7-11 years and their families between 2017 and 2021. We are collecting detailed parent and child questionnaires, cognitive and sensorimotor assessments, blood pressure, anthropometry and blood samples from parents and children. Dual x-ray absorptiometry body scans, accelerometry and urine samples are collected on subsamples. Informed consent is collected for continued routine data linkage to health, social care and education records. A range of engagement activities are being used to raise the profile of BiB and to disseminate findings. DISCUSSION: Our multi-method approach to recruitment and assessment provides an efficient method of collecting rich data on all family members. Data collected will enhance BiB as a resource for the international research community to study the interplay between ethnicity, socioeconomic circumstances and biology in relation to cardiometabolic health, mental health, education, cognitive and sensorimotor development and wellbeing

    A solution method for the sub-surface stresses and local deflection of a semi-infinite inhomogeneous elastic medium

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    This paper proposes analytical Fourier series solutions (based on the Airy stress function) for the local deflection and subsurface stress field of a two-dimensional graded elastic solid loaded by a pre-determined pressure distribution. We present a selection of numerical results for a simple sinusoidal pressure which indicates how the inhomogeneity of the solid affects its behaviour. The model is then adapted and used to derive an iterative algorithm which may be used to solve for the contact half width and pressure induced from contact with a rigid punch. Finally, the contact of a rigid cylindrical stamp is studied and our results compared to those predicted by Hertzian theory. It is found that solids with a slowly varying elastic modulus produce results in good agreement with those of Hertz whilst more quickly varying elastic moduli which correspond to solids that become stiffer below the surface give rise to larger maximum pressures and stresses whilst the contact pressure is found to act over a smaller area

    The role of parental achievement goals in predicting autonomy-supportive and controlling parenting

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    Although autonomy-supportive and controlling parenting are linked to numerous positive and negative child outcomes respectively, fewer studies have focused on their determinants. Drawing on achievement goal theory and self-determination theory, we propose that parental achievement goals (i.e., achievement goals that parents have for their children) can be mastery, performance-approach or performance-avoidance oriented and that types of goals predict mothers' tendency to adopt autonomy-supportive and controlling behaviors. A total of 67 mothers (aged 30-53 years) reported their goals for their adolescent (aged 13-16 years; 19.4 % girls), while their adolescent evaluated their mothers' behaviors. Hierarchical regression analyses showed that parental performance-approach goals predict more controlling parenting and prevent acknowledgement of feelings, one autonomy-supportive behavior. In addition, mothers who have mastery goals and who endorse performance-avoidance goals are less likely to use guilt-inducing criticisms. These findings were observed while controlling for the effect of maternal anxiety

    Spectrophotometric determination of the formation constants of calcium(II) complexes with 2,2'-bipyridyl and 1,10-phenanthroline in acetonitrile

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    AbstractThe oxygen-evolving complex (OEC), which consists of a calcium-manganese cluster, is the reaction center of the Photosystem II. At this catalytic site, the water-splitting reaction in dioxygen and hydronium ions occurs. In order to partially reproduce the water splitting process, several studies have reported the synthesis of functional model complexes. Nevertheless, there is a small amount of reports, concerning the spectral behavior of calcium complexes or the calcium role in the cluster. In this work, in order to explore the absorption spectrum of calcium species in acetonitrile, an equilibrium study of the calcium complexes with 2,2'-bipyridyl or 1,10-phenanthroline, was carried out. The formation constants and the calculated electronic spectrum of each complex was obtained by a modified method of continuous variations consisting in a correlation of the experimental spectrophotometric data with the HypSpec software. The values of the formation constants for the calcium(II) complexes with 2,2'-bipyridyl and 1,10-phenanthroline, are Log β110 = 4.39 ± 0.02 and Log β110 = 5.94 ± 0.05, respectively

    Strategies to self-manage side-effects of adjuvant endocrine therapy among breast cancer survivors: an umbrella review of empirical evidence and clinical guidelines

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    Purpose: Side-effects of adjuvant endocrine therapy (AET) are common in breast cancer survivors, and can affect adherence to treatment. We synthesised the evidence for strategies to self-manage these side-effects. Methods: We searched for systematic reviews and clinical guidelines on self-management strategies for AET side-effects (arthralgia, fatigue, hot flashes, gastrointestinal discomfort, nausea, vulvovaginal symptoms, and sleep disturbance). We searched oncology organisation’s websites and eight databases (Inception-November 2020). Screening, data extraction and quality assessment were completed independently in duplicate. PROSPERO: 2019CRD4201914001. Results: We identified 33 systematic reviews and 18 clinical guidelines. 21% of reviews were high quality, and the average quality score for guidelines was 44%. Evidence for most strategies was absent or weak. There was consensus from a low-quality review and multiple guidelines to recommend moisturisers, gels and lubricants for vulvovaginal symptoms. Evidence was weak for physical activity for self-managing most symptoms, although two high-quality reviews indicated yoga and aerobic exercise could reduce fatigue. Primary research was often biased by weak and underpowered study designs. Eleven reviews did not report information on adverse events. Conclusions: Most self-management strategies for breast cancer survivors experiencing side-effects from AET lack evidence. Primary research is needed using high-quality well-powered designs focusing on implementable strategies. Implications for Cancer Survivors: Patients and clinicians should be aware that although the risk of harm is low for these self-management strategies, the likelihood of benefit is often unclear. Women should consider moisturisers, gels or lubricants for self-managing vulvovaginal symptoms, and yoga or aerobic exercise for alleviating fatigue

    Nutrition intervention is beneficial in oncology outpatients receiving radiotherapy to the gastrointestinal or head and neck area

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    Background: Malnutrition occurs frequently in patients with cancer of the gastrointestinal or head and neck area and can lead to negative outcomes. Objective: To determine the impact of early and intensive nutrition intervention on body weight, body composition, nutritional status, global quality of life and physical function compared to usual practice in oncology outpatients receiving radiotherapy to the gastrointestinal or head and neck area. Design: Outpatients commencing at least 20 fractions of radiotherapy to the gastrointestinal or head and neck area were randomised to receive intensive, individualised nutrition counselling by a dietitian using a standard protocol and oral supplements if required, or the usual practice of the centre (general advice and nutrition booklet). Outcome parameters were measured at baseline and four, eight, and twelve weeks after commencing radiotherapy using valid and reliable tools. Results: Sixty patients (51M;9F; mean age 61.9 yr +/- 14.0) were randomised to receive either nutrition intervention (n=29) or usual care (n=31). The nutrition intervention group had statistically smaller deteriorations in weight (p < 0.001), nutritional status (p = 0.020) and global quality of life (p = 0.009) compared with those receiving usual care. Clinically, but not statistically significant differences in fat-free mass were observed between the groups (p = 0.195). Conclusions Early and intensive nutrition intervention appears beneficial in terms of minimising weight loss, deterioration in nutritional status, global quality of life and physical function in oncology outpatients receiving radiotherapy to the gastrointestinal or head and neck area. Weight maintenance in this population leads to beneficial outcomes and suggests that this, rather than weight gain, may be a more appropriate aim of nutrition intervention
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