1,293 research outputs found

    Integrating Fisheries Into Irrigation Planning and Management

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    Expectations of progression to university among pupils in rural communities : the role of social influences

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    Funding: Authors thank the University of St Andrews, the Scottish Government and the Scottish Funding Council for their support.This paper examines the social influences determining S5/Year 12 and S6/Year 13 (final year) pupils’ expectations of progression to university in a Scottish rural context in which pupils are less likely to go to university. In particular, we investigate the extent to which perceived support from parents, peers, and school, taking into account pupils’ own evaluation of their qualifications, is associated with their self-assessed likelihood of university entry. Our sample is drawn from a repeated questionnaire completed by pupils at three Scottish state secondary schools whose catchment areas are mainly rural. Our results are twofold. First, it is the perceived enthusiasm of their parents and peers, rather than their school, which is primarily correlated with pupils’ expectations of progression to university all else equal. This is true whether pupils report low or high qualification barriers to university entry. Second, perceived parental support is stronger for those whose parents had themselves attended university, especially for pupils identifying low qualification barriers. Given that school support appears to lack significance in pupils’ expectations of progression to university in this context, there is potentially scope for policymakers, universities and schools located in these rural communities to strengthen this influence.Publisher PDFPeer reviewe

    Interpreting Mendelian-randomization estimates of the effects of categorical exposures such as disease status and educational attainment

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    BACKGROUND: Mendelian randomization has been previously used to estimate the effects of binary and ordinal categorical exposures—e.g. Type 2 diabetes or educational attainment defined by qualification—on outcomes. Binary and categorical phenotypes can be modelled in terms of liability—an underlying latent continuous variable with liability thresholds separating individuals into categories. Genetic variants influence an individual’s categorical exposure via their effects on liability, thus Mendelian-randomization analyses with categorical exposures will capture effects of liability that act independently of exposure category. METHODS AND RESULTS: We discuss how groups in which the categorical exposure is invariant can be used to detect liability effects acting independently of exposure category. For example, associations between an adult educational-attainment polygenic score (PGS) and body mass index measured before the minimum school leaving age (e.g. age 10 years), cannot indicate the effects of years in full-time education on this outcome. Using UK Biobank data, we show that a higher educational-attainment PGS is strongly associated with lower smoking initiation and higher odds of glasses use at age 15 years. These associations were replicated in sibling models. An orthogonal approach using the raising of the school leaving age (ROSLA) policy change found that individuals who chose to remain in education to age 16 years before the reform likely had higher liability to educational attainment than those who were compelled to remain in education to age 16 years after the reform, and had higher income, lower pack-years of smoking, higher odds of glasses use and lower deprivation in adulthood. These results suggest that liability to educational attainment is associated with health and social outcomes independently of years in full-time education. CONCLUSIONS: Mendelian-randomization studies with non-continuous exposures should be interpreted in terms of liability, which may affect the outcome via changes in exposure category and/or independently

    An assessment of intermediary roles in payments for ecosystem services schemes in the context of catchment management: An example from South West England

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    Payments for Ecosystems Services (PES) schemes are an underdeveloped component of the policy mix for catchment management in many countries. The importance of intermediaries to such schemes is acknowledged in the literature but few studies go beyond theory to evaluate practice. This paper analyses generic intermediary functions for PES. It then evaluates an innovative example from southwest England that provides illustrations, and some lessons regarding necessary capabilities and characteristics for intermediaries, and understanding of their form, functions and modalities. The ‘UpStream Thinking’ project was co-developed by a private water company and an environmental charity. The former translated effective demand from shareholders and water customers for improved raw water quality into finance, whilst the latter had capabilities for catchment-scale on-farm delivery and trusted acceptance as an intermediary. While any sector can potentially provide a PES intermediary, the value driven, not-for-profit and politically neutral voluntary sector proves to be a good fit. Such ‘boundary organisations’ are also well placed for horizontal coordination of catchment management authorities and actions

    Inefficiency and Environmental Risks associated with Nutrient Use in Agriculture within China and the UK

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    The stocks and flows of nitrogen (N) and phosphorus (P) were quantified for five case studies, representing contrasting agricultural systems in China and the UK. The input of nutrients exceeded the output of nutrients in agricultural products for all five systems, although to varying degrees between individual case studies.Excessive input of nutrients for each system increases the risk of negative environmental impacts on soil, air and water quality. Soils accumulate nutrient stocks due to excessive nutrient inputs, representing an under-exploited nutrient reserve that could contribute to future agriculture production. Livestock and crop production are increasingly disconnected in China. Manure application was limited to high-value fruit and vegetable crops in the systems analysed, but often without adequate accounting for the nutrient content of the applied manure.Pathways to improve the efficiency of nutrient use are identified

    Place attachment in deprived neighbourhoods: The impacts of population turnover and social mix

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    This paper examines the determinants of individual place attachment, focussing in particular on differences between deprived and others neighbourhoods, and on the impacts of population turnover and social mix. It uses a multi-level modelling approach to take account of both individual- and neighbourhood-level determinants. Data are drawn from a large sample government survey, the Citizenship Survey 2005, to which a variety of neighbourhood-level data have been attached. The paper argues that attachment is significantly lower in more deprived neighbourhoods primarily because these areas have weaker social cohesion but that, in other respects, the drivers of attachment are the same. Turnover has modest direct impacts on attachment through its effect on social cohesion. Social mix has very limited impacts on attachment and the effects vary between social groups. In general, higher status or more dominant groups appear less tolerant of social mix

    Assortative mating and within-spouse pair comparisons

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    Spousal comparisons have been proposed as a design that can both reduce confounding and estimate effects of the shared adulthood environment. However, assortative mating, the process by which individuals select phenotypically (dis)similar mates, could distort associations when comparing spouses. We evaluated the use of spousal comparisons, as in the within-spouse pair (WSP) model, for aetiological research such as genetic association studies. We demonstrated that the WSP model can reduce confounding but may be susceptible to collider bias arising from conditioning on assorted spouse pairs. Analyses using UK Biobank spouse pairs found that WSP genetic association estimates were smaller than estimates from random pairs for height, educational attainment, and BMI variants. Within-sibling pair estimates, robust to demographic and parental effects, were also smaller than random pair estimates for height and educational attainment, but not for BMI. WSP models, like other within-family models, may reduce confounding from demographic factors in genetic association estimates, and so could be useful for triangulating evidence across study designs to assess the robustness of findings. However, WSP estimates should be interpreted with caution due to potential collider bias

    Wolbachia and DNA barcoding insects: patterns, potential and problems

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    Wolbachia is a genus of bacterial endosymbionts that impacts the breeding systems of their hosts. Wolbachia can confuse the patterns of mitochondrial variation, including DNA barcodes, because it influences the pathways through which mitochondria are inherited. We examined the extent to which these endosymbionts are detected in routine DNA barcoding, assessed their impact upon the insect sequence divergence and identification accuracy, and considered the variation present in Wolbachia COI. Using both standard PCR assays (Wolbachia surface coding protein – wsp), and bacterial COI fragments we found evidence of Wolbachia in insect total genomic extracts created for DNA barcoding library construction. When >2 million insect COI trace files were examined on the Barcode of Life Datasystem (BOLD) Wolbachia COI was present in 0.16% of the cases. It is possible to generate Wolbachia COI using standard insect primers; however, that amplicon was never confused with the COI of the host. Wolbachia alleles recovered were predominantly Supergroup A and were broadly distributed geographically and phylogenetically. We conclude that the presence of the Wolbachia DNA in total genomic extracts made from insects is unlikely to compromise the accuracy of the DNA barcode library; in fact, the ability to query this DNA library (the database and the extracts) for endosymbionts is one of the ancillary benefits of such a large scale endeavor – for which we provide several examples. It is our conclusion that regular assays for Wolbachia presence and type can, and should, be adopted by large scale insect barcoding initiatives. While COI is one of the five multi-locus sequence typing (MLST) genes used for categorizing Wolbachia, there is limited overlap with the eukaryotic DNA barcode region
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