323 research outputs found

    Measurement and Understanding of Emissions over London and Southern England by Airborne Eddy-Covariance

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    High anthropogenic emissions are a global problem with clear links existing between poor air quality and premature mortality, which is of great alarm to organisations such as the World Health Organisation (WHO). In Europe, high emissions of nitrogen oxides (NOx) are a concern with concentrations plateauing over the last 15 years. Emission assessment is a key part of the UK’s air quality strategy; this is done so by using tools such as the National Atmospheric Emissions Inventory (NAEI), to report annual emissions to the EU to meet strict air quality regulations. Due to the high importance placed on inventories such as the NAEI, their accuracy is vital. This thesis details the development and implementation of an airborne eddy−covariance (AEC) strategy to measure anthropogenic fluxes over highly polluted areas, and compare these findings to UK emission inventories. The Ozone Precursor Fluxes in an Urban Environment (OPFUE) campaign was run over two consecutive years, aiming at evaluating emissions from London and Southern England. NOx emissions were evaluated over London showing high emissions coming from central areas. Comparison to the NAEI found NOx emissions were being underestimation by up to a factor of 2. Refinement using the NAEI + road transport estimates scaled via road side measurements showed good improvement, suggesting the need to refine road transport estimates used in the NAEI. A variety of VOC emissions were also measured over London and Southern England. Measured VOCs over London showed good agreement to the NAEI, and highlighted the successful reduction of VOC emissions through air quality strategies. Measured biogenic emissions of isoprene were found to be higher than air quality model estimates, which could have implications towards regional air quality due to ground level ozone formation. Overall, the described methodology allows for real-time assessment of emission inventories which is key if the UK is to see improvements in its air quality

    The dark triad in male and female athletes and non-athletes: Group differences and psychometric properties of the short dark triad (SD3)

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    © 2019 Elsevier Ltd Objectives: The Short Dark Triad (SD3) is a popular, brief measure of narcissism, Machiavellianism, and psychopathy, which are known as the Dark Triad. The present study adopted this measure and had two aims. First, to assess the psychometric properties of the SD3 with a focus on measurement invariance across gender, athletic expertise, and sport type. Second, to examine mean differences in Dark Triad scores across these groups. Design: Cross-sectional. Method: In total, 1258 participants (625 women; mean age 23.47 years) with a range of athletic experience (non-athletes, N = 408; amateur, N = 557; elite, N = 293) from team (N = 577) and individual (N = 273) sports completed the SD3. Factorial validity was assessed using exploratory structural equation modelling. Results: Analyses indicated that the three-factor model provided adequate fit, however, a bifactor model incorporating the three specific factors and a general factor, provided superior fit to the data. Moreover, invariance testing suggested some inconsistency in the observed factor structures across groups. In addition, findings indicated group differences with men scoring higher than women, athletes with greater expertise scoring higher than those with less expertise, and individual athletes scoring higher than team athletes across all factors. Conclusions: We suggest that researchers continue to use the SD3 using both composite and subscale scores, but recommend caution when interpreting subscale scores among women and team athletes until further psychometric work has been conducted within these populations. Our findings also suggest that the Dark Triad may be worth examining in future studies in sport

    Intermittent energy restriction induces changes in breast gene expression and systemic metabolism

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    Background: Observational studies suggest weight loss and energy restriction reduce breast cancer risk. Intermittent energy restriction (IER) reduces weight to the same extent as, or more than equivalent continuous energy restriction (CER) but the effects of IER on normal breast tissue and systemic metabolism as indicators of breast cancer risk are unknown. Methods: We assessed the effect of IER (two days of 65 % energy restriction per week) for one menstrual cycle on breast tissue gene expression using Affymetrix GeneChips, adipocyte size by morphometry, and systemic metabolism (insulin resistance, lipids, serum and urine metabolites, lymphocyte gene expression) in 23 overweight premenopausal women at high risk of breast cancer. Unsupervised and supervised analyses of matched pre and post IER biopsies in 20 subjects were performed, whilst liquid and gas chromatography mass spectrometry assessed corresponding changes in serum and urine metabolites in all subjects after the two restricted and five unrestricted days of the IER. Results: Women lost 4.8 % (±2.0 %) of body weight and 8.0 % (±5.0 %) of total body fat. Insulin resistance (homeostatic model assessment (HOMA)) reduced by 29.8 % (±17.8 %) on the restricted days and by 11 % (±34 %) on the unrestricted days of the IER. Five hundred and twenty-seven metabolites significantly increased or decreased during the two restricted days of IER. Ninety-one percent of these returned to baseline after 5 days of normal eating. Eleven subjects (55 %) displayed reductions in energy restriction-associated metabolic gene pathways including lipid synthesis, gluconeogenesis and glycogen synthesis. Some of these women also had increases in genes associated with breast epithelial cell differentiation (secretoglobulins, milk proteins and mucins) and decreased collagen synthesis (TNMD, PCOLCE2, TIMP4). There was no appreciable effect of IER on breast gene expression in the other nine subjects. These groups did not differ in the degree of changes in weight, total body fat, fat cell size or serum or urine metabolomic markers. Corresponding gene changes were not seen in peripheral blood lymphocytes. Conclusion: The transcriptional response to IER is variable in breast tissue, which was not reflected in the systemic response, which occurred in all subjects. The mechanisms of breast responsiveness/non-responsiveness require further investigation. Trial registration:ISRCTN7791648731/07/2012

    Long- and short-term outcomes in renal allografts with deceased donors: A large recipient and donor genome-wide association study.

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    Improvements in immunosuppression have modified short-term survival of deceased-donor allografts, but not their rate of long-term failure. Mismatches between donor and recipient HLA play an important role in the acute and chronic allogeneic immune response against the graft. Perfect matching at clinically relevant HLA loci does not obviate the need for immunosuppression, suggesting that additional genetic variation plays a critical role in both short- and long-term graft outcomes. By combining patient data and samples from supranational cohorts across the United Kingdom and European Union, we performed the first large-scale genome-wide association study analyzing both donor and recipient DNA in 2094 complete renal transplant-pairs with replication in 5866 complete pairs. We studied deceased-donor grafts allocated on the basis of preferential HLA matching, which provided some control for HLA genetic effects. No strong donor or recipient genetic effects contributing to long- or short-term allograft survival were found outside the HLA region. We discuss the implications for future research and clinical application

    Extensive field evidence for the release of HONO from the photolysis of nitrate aerosols

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    Particulate nitrate ([Formula: see text]) has long been considered a permanent sink for NO(x) (NO and NO(2)), removing a gaseous pollutant that is central to air quality and that influences the global self-cleansing capacity of the atmosphere. Evidence is emerging that photolysis of [Formula: see text] can recycle HONO and NO(x) back to the gas phase with potentially important implications for tropospheric ozone and OH budgets; however, there are substantial discrepancies in “renoxification” photolysis rate constants. Using aircraft and ground-based HONO observations in the remote Atlantic troposphere, we show evidence for renoxification occurring on mixed marine aerosols with an efficiency that increases with relative humidity and decreases with the concentration of [Formula: see text] , thus largely reconciling the very large discrepancies in renoxification photolysis rate constants found across multiple laboratory and field studies. Active release of HONO from aerosol has important implications for atmospheric oxidants such as OH and O(3) in both polluted and clean environments

    Non-methane volatile organic compounds emitted from domestic fuels in Delhi: Emission factors and total city-wide emissions

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    In controlled laboratory conditions, 62 samples of domestic fuels collected from 56 grids of Delhi were burnt to quantify the emissions of 23 non-methane volatile organic compounds (NMVOCs), i.e., alkanes (11), alkenes (6), alkynes (1) and aromatic compounds (5). The domestic fuels used for residential activities were comprised of 20 unique types of fuel woods, 3 species of crop residue, dung cakes and coal. These fuels are primarily used for cooking and water/space heating during winters. The current study reports the total emission budget of NMVOCs from domestic burning over Delhi. Furthermore, this study also compares the differences in EFs of NMVOCs which are calculated for different burning cycles and sample collection methods. The EFs of NMVOCs calculated from the samples collected during the flaming stage using canisters were analysed for 23 NMVOCs and then compared with same species emitted from complete burning cycle. In addition to this, 10 consumption and emission hotspot grids were also identified in Delhi; based on the ground survey and laboratory simulated results. The total annual usage of domestic fuels for the year 2019 was found to be 0.415 Mt/yr (million tonnes) in Delhi. 12.01 Gg/yr of annual NMVOC emissions was calculated from domestic fuel burning in which the emissions from dung cake and fuel wood dominated with 6.6 Gg/yr and 5.4 Gg/yr, respectively. The EFs of NMVOCs calculated using canister and online collection method differ significantly from each other. The flaming stage presented enhanced emissions compared to the complete burning cycle by ~7 times which suggests that the method of data analysis and the period of sample collection play a pivotal role in the preparation of an emission inventory and estimating the budget

    Large Methane Emission Fluxes Observed From Tropical Wetlands in Zambia

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    Methane (CH4) is a potent greenhouse gas with a warming potential 84 times that of carbon dioxide (CO2) over a 20-year period. Atmospheric CH4 concentrations have been rising since the nineteenth century but the cause of large increases post-2007 is disputed. Tropical wetlands are thought to account for ∌20% of global CH4 emissions, but African tropical wetlands are understudied and their contribution is uncertain. In this work, we use the first airborne measurements of CH4 sampled over three wetland areas in Zambia to derive emission fluxes. Three independent approaches to flux quantification from airborne measurements were used: Airborne mass balance, airborne eddy-covariance, and an atmospheric inversion. Measured emissions (ranging from 5 to 28 mg m−2 hr−1) were found to be an order of magnitude greater than those simulated by land surface models (ranging from 0.6 to 3.9 mg m−2 hr−1), suggesting much greater emissions from tropical wetlands than currently accounted for. The prevalence of such underestimated CH4 sources may necessitate additional reductions in anthropogenic greenhouse gas emissions to keep global warming below a threshold of 2°C above preindustrial levels

    Children must be protected from the tobacco industry's marketing tactics.

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    Contribution of copy number variants to schizophrenia from a genome-wide study of 41,321 subjects

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    Copy number variants (CNVs) have been strongly implicated in the genetic etiology of schizophrenia (SCZ). However, genome-wide investigation of the contribution of CNV to risk has been hampered by limited sample sizes. We sought to address this obstacle by applying a centralized analysis pipeline to a SCZ cohort of 21,094 cases and 20,227 controls. A global enrichment of CNV burden was observed in cases (OR=1.11, P=5.7×10−15), which persisted after excluding loci implicated in previous studies (OR=1.07, P=1.7 ×10−6). CNV burden was enriched for genes associated with synaptic function (OR = 1.68, P = 2.8 ×10−11) and neurobehavioral phenotypes in mouse (OR = 1.18, P= 7.3 ×10−5). Genome-wide significant evidence was obtained for eight loci, including 1q21.1, 2p16.3 (NRXN1), 3q29, 7q11.2, 15q13.3, distal 16p11.2, proximal 16p11.2 and 22q11.2. Suggestive support was found for eight additional candidate susceptibility and protective loci, which consisted predominantly of CNVs mediated by non-allelic homologous recombination

    Mapping genomic loci implicates genes and synaptic biology in schizophrenia

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    Schizophrenia has a heritability of 60-80%1, much of which is attributable to common risk alleles. Here, in a two-stage genome-wide association study of up to 76,755 individuals with schizophrenia and 243,649 control individuals, we report common variant associations at 287 distinct genomic loci. Associations were concentrated in genes that are expressed in excitatory and inhibitory neurons of the central nervous system, but not in other tissues or cell types. Using fine-mapping and functional genomic data, we identify 120 genes (106 protein-coding) that are likely to underpin associations at some of these loci, including 16 genes with credible causal non-synonymous or untranslated region variation. We also implicate fundamental processes related to neuronal function, including synaptic organization, differentiation and transmission. Fine-mapped candidates were enriched for genes associated with rare disruptive coding variants in people with schizophrenia, including the glutamate receptor subunit GRIN2A and transcription factor SP4, and were also enriched for genes implicated by such variants in neurodevelopmental disorders. We identify biological processes relevant to schizophrenia pathophysiology; show convergence of common and rare variant associations in schizophrenia and neurodevelopmental disorders; and provide a resource of prioritized genes and variants to advance mechanistic studies
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