67 research outputs found

    Understanding the Effects of Cross-Linking Density on the Self-Healing Performance of Epoxidized Natural Rubber and Natural Rubber

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    [Image: see text] The demand for self-healing elastomers is increasing due to the potential opportunities such materials offer in reducing down-time and cost through extended product lifetimes and reduction of waste. However, further understanding of self-healing mechanisms and processes is required in order to develop a wider range of commercially applicable materials with self-healing properties. Epoxidized natural rubber (ENR) is a derivative of polyisoprene. ENR25 and ENR50 are commercially available materials with 25 and 50 mol % epoxidation, respectively. Recently, reports of the use of ENR in self-healing materials have begun to emerge. However, to date, there has been limited analysis of the self-healing mechanism at the molecular level. The aim of this work is to gain understanding of the relevant self-healing mechanisms through systematic characterization and analysis of the effect of cross-linking on the self-healing performance of ENR and natural rubber (NR). In our study, cross-linking of ENR and NR with dicumyl peroxide and sulfur to provide realistic models of commercial rubber formulations is described, and a cross-linking density of 5 × 10(–5) mol cm(–3) in sulfur-cured ENR is demonstrated to achieve a healing efficiency of 143% for the tensile strength. This work provides the foundation for further modification of ENR, with the goal of understanding and controlling ENR’s self-healing ability for future applications

    The Radial Velocity TATOOINE Search for Circumbinary Planets: Planet Detection Limits for a Sample of Double-lined Binary Stars - Initial Results from Keck I/Hires, Shane/CAT/Hamspec and TNG/Sarg Observations

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    We present preliminary results of the first and on-going radial velocity survey for circumbinary planets. With a novel radial velocity technique employing an iodine absorption cell we achieve an unprecedented RV precision of up to 2 m/s for double-lined binary stars. The high resolution spectra collected with the Keck I/Hires, TNG/Sarg and Shane/CAT/Hamspec telescopes/spectrographs over the years 2003-2008 allow us to derive RVs and compute planet detection limits for ten double-lined binary stars. For this initial sample of targets, we can rule out planets on dynamically stable orbits with masses as small as ~0.3 to 3 MJup for the orbital periods of up to ~5.3 years. Even though the presented sample of stars is too small to make any strong conclusions, it is clear that the search for circumbinary planets is now technique-wise possible and eventually will provide new constraints for the planet formation theories.Comment: to appear in Ap

    Prasugrel versus Clopidogrel for Acute Coronary Syndromes without Revascularization

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    peer reviewedBACKGROUND: The effect of intensified platelet inhibition for patients with unstable angina or myocardial infarction without ST-segment elevation who do not undergo revascularization has not been delineated. METHODS: In this double-blind, randomized trial, in a primary analysis involving 7243 patients under the age of 75 years receiving aspirin, we evaluated up to 30 months of treatment with prasugrel (10 mg daily) versus clopidogrel (75 mg daily). In a secondary analysis involving 2083 patients 75 years of age or older, we evaluated 5 mg of prasugrel versus 75 mg of clopidogrel. RESULTS: At a median follow-up of 17 months, the primary end point of death from cardiovascular causes, myocardial infarction, or stroke among patients under the age of 75 years occurred in 13.9% of the prasugrel group and 16.0% of the clopidogrel group (hazard ratio in the prasugre

    Enhancement of a modified Mediterranean-style, low glycemic load diet with specific phytochemicals improves cardiometabolic risk factors in subjects with metabolic syndrome and hypercholesterolemia in a randomized trial

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    <p>Abstract</p> <p>Background</p> <p>As the worldwide dietary pattern becomes more westernized, the metabolic syndrome is reaching epidemic proportions. Lifestyle modifications including diet and exercise are recommended as first-line intervention for treating metabolic syndrome. Previously, we reported that a modified Mediterranean-style, low glycemic load diet with soy protein and phytosterols had a more favorable impact than the American Heart Association Step 1 diet on cardiovascular disease (CVD) risk factors. Subsequently, we screened for phytochemicals with a history of safe use that were capable of increasing insulin sensitivity through modulation of protein kinases, and identified hops <it>rho </it>iso-alpha acid and acacia proanthocyanidins. The objective of this study was to investigate whether enhancement of a modified Mediterranean-style, low glycemic load diet (MED) with specific phytochemicals (soy protein, phytosterols, <it>rho </it>iso-alpha acids and proanthocyanidins; PED) could improve cardiometabolic risk factors in subjects with metabolic syndrome and hypercholesterolemia.</p> <p>Methods</p> <p>Forty-nine subjects with metabolic syndrome and hypercholesterolemia, aged 25–80, entered a randomized, 2-arm, 12-week intervention trial; 23 randomized to the MED arm; 26 to the PED arm. Forty-four subjects completed at least 8 weeks [MED (<it>n </it>= 19); PED (<it>n </it>= 25)]. All subjects were instructed to follow the same aerobic exercise program. Three-day diet diaries and 7-day exercise diaries were assessed at each visit. Fasting blood samples were collected at baseline, 8 and 12 weeks for analysis.</p> <p>Results</p> <p>Both arms experienced equal weight loss (MED: -5.7 kg; PED: -5.9 kg). However, at 12 weeks, the PED arm experienced greater reductions (<it>P </it>< 0.05) in cholesterol, non-HDL cholesterol, triglycerides (TG), cholesterol/HDL and TG/HDL compared with the MED arm. Only the PED arm experienced increased HDL (<it>P </it>< 0.05) and decreased TG/HDL (<it>P </it>< 0.01), and continued reduction in apo B/apo A-I from 8 to 12 weeks. Furthermore, 43% of PED subjects vs. only 22% of MED subjects had net resolution of metabolic syndrome. The Framingham 10-year CVD risk score decreased by 5.6% in the PED arm (<it>P </it>< 0.01) and 2.9% in the MED arm (<it>P </it>< 0.05).</p> <p>Conclusion</p> <p>These results demonstrate that specific phytochemical supplementation increased the effectiveness of the modified Mediterranean-style low glycemic load dietary program on variables associated with metabolic syndrome and CVD.</p

    Achieving benchmarks for national quality indicators reduces recurrence and progression in non-muscle-invasive bladder cancer

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    Background Noncompliance with evidence-based interventions and guidelines contributes to significant and variable recurrence and progression in patients with non–muscle-invasive bladder cancer (NMIBC). The implementation of a quality performance indicator (QPI) programme in Scotland’s National Health Service (NHS) aimed to improve cancer outcomes and reduce nationwide variance. Objective To evaluate the effect of hospitals achieving benchmarks for two specific QPIs on time to recurrence and progression in NMIBC. Design, setting, and participants QPIs for bladder cancer (BC) were enforced nationally in April 2014. NHS health boards collected prospective data on all new BC patients. Prospectively recorded surveillance data were pooled from 12 collaborating centres. Intervention QPIs of interest were (1) hospitals achieving detrusor muscle (DM) sampling target at initial transurethral resection of bladder tumour (TURBT) and (2) use of single instillation of mitomycin C after TURBT (SI-MMC). Outcome measurements and statistical analysis The primary and secondary endpoints were time to recurrence and progression, respectively. Kaplan-Meier and Cox multivariable regression analyses were performed. Key findings and limitations Between April 1, 2014 and March 31, 2017, we diagnosed 3899 patients with new BC, of which 2688 were NMIBC . With a median follow up of 60.3 mo, hospitals achieving the DM sampling target had a 5.4% lower recurrence rate at 5 yr than hospitals not achieving this target (442/1136 [38.9%] vs 677/1528 [44.3%], 95% confidence interval [CI] = 1.6–9.2, p = 0.005). SI-MMC was associated with a 20.4% lower recurrence rate (634/1791 [35.4%] vs 469/840 [55.8%], 95% CI = 16.4–24.5, p &lt; 0.001). On Cox multivariable regression, meeting the DM target and SI-MMC were associated with significant improvement in recurrence (hazard ratio [HR] 0.81, 95% CI = 0.73–0.91, p = 0.0002 and HR 0.66, 95% CI = 0.59–0.74, p &lt; 0.004, respectively) as well as progression-free survival (HR 0.62, 95% CI = 0.45–0.84, p = 0.002 and HR 0.65, 95% CI = 0.49–0.87, p = 0.004, respectively). We did not have a national multicentre pre-QPI control. Conclusions Within a national QPI programme, meeting targets for sampling DM and SI-MMC in the real world were independently associated with delays to recurrence and progression in NMIBC patients. Patient summary Following the first 3 yr of implementing a novel quality performance indicator programme in Scotland, we evaluated compliance and outcomes in non–muscle-invasive bladder cancer. In 2688 patients followed up for 5 yr, we found that achieving targets for sampling detrusor muscle and the single instillation of mitomycin C during and after transurethral resection of bladder tumour, respectively, were associated with delays in cancer recurrence and progression

    Roadmap on Photovoltaic Absorber Materials for Sustainable Energy Conversion

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    Photovoltaics (PVs) are a critical technology for curbing growing levels of anthropogenic greenhouse gas emissions, and meeting increases in future demand for low-carbon electricity. In order to fulfil ambitions for net-zero carbon dioxide equivalent (CO2eq) emissions worldwide, the global cumulative capacity of solar PVs must increase by an order of magnitude from 0.9 TWp in 2021 to 8.5 TWp by 2050 according to the International Renewable Energy Agency, which is considered to be a highly conservative estimate. In 2020, the Henry Royce Institute brought together the UK PV community to discuss the critical technological and infrastructure challenges that need to be overcome to address the vast challenges in accelerating PV deployment. Herein, we examine the key developments in the global community, especially the progress made in the field since this earlier roadmap, bringing together experts primarily from the UK across the breadth of the photovoltaics community. The focus is both on the challenges in improving the efficiency, stability and levelized cost of electricity of current technologies for utility-scale PVs, as well as the fundamental questions in novel technologies that can have a significant impact on emerging markets, such as indoor PVs, space PVs, and agrivoltaics. We discuss challenges in advanced metrology and computational tools, as well as the growing synergies between PVs and solar fuels, and offer a perspective on the environmental sustainability of the PV industry. Through this roadmap, we emphasize promising pathways forward in both the short- and long-term, and for communities working on technologies across a range of maturity levels to learn from each other.Comment: 160 pages, 21 figure

    A large-scale genome-wide association study meta-analysis of cannabis use disorder

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    Summary Background Variation in liability to cannabis use disorder has a strong genetic component (estimated twin and family heritability about 50–70%) and is associated with negative outcomes, including increased risk of psychopathology. The aim of the study was to conduct a large genome-wide association study (GWAS) to identify novel genetic variants associated with cannabis use disorder. Methods To conduct this GWAS meta-analysis of cannabis use disorder and identify associations with genetic loci, we used samples from the Psychiatric Genomics Consortium Substance Use Disorders working group, iPSYCH, and deCODE (20 916 case samples, 363 116 control samples in total), contrasting cannabis use disorder cases with controls. To examine the genetic overlap between cannabis use disorder and 22 traits of interest (chosen because of previously published phenotypic correlations [eg, psychiatric disorders] or hypothesised associations [eg, chronotype] with cannabis use disorder), we used linkage disequilibrium score regression to calculate genetic correlations. Findings We identified two genome-wide significant loci: a novel chromosome 7 locus (FOXP2, lead single-nucleotide polymorphism [SNP] rs7783012; odds ratio [OR] 1·11, 95% CI 1·07–1·15, p=1·84 × 10−9) and the previously identified chromosome 8 locus (near CHRNA2 and EPHX2, lead SNP rs4732724; OR 0·89, 95% CI 0·86–0·93, p=6·46 × 10−9). Cannabis use disorder and cannabis use were genetically correlated (rg 0·50, p=1·50 × 10−21), but they showed significantly different genetic correlations with 12 of the 22 traits we tested, suggesting at least partially different genetic underpinnings of cannabis use and cannabis use disorder. Cannabis use disorder was positively genetically correlated with other psychopathology, including ADHD, major depression, and schizophrenia. Interpretation These findings support the theory that cannabis use disorder has shared genetic liability with other psychopathology, and there is a distinction between genetic liability to cannabis use and cannabis use disorder. Funding National Institute of Mental Health; National Institute on Alcohol Abuse and Alcoholism; National Institute on Drug Abuse; Center for Genomics and Personalized Medicine and the Centre for Integrative Sequencing; The European Commission, Horizon 2020; National Institute of Child Health and Human Development; Health Research Council of New Zealand; National Institute on Aging; Wellcome Trust Case Control Consortium; UK Research and Innovation Medical Research Council (UKRI MRC); The Brain & Behavior Research Foundation; National Institute on Deafness and Other Communication Disorders; Substance Abuse and Mental Health Services Administration (SAMHSA); National Institute of Biomedical Imaging and Bioengineering; National Health and Medical Research Council (NHMRC) Australia; Tobacco-Related Disease Research Program of the University of California; Families for Borderline Personality Disorder Research (Beth and Rob Elliott) 2018 NARSAD Young Investigator Grant; The National Child Health Research Foundation (Cure Kids); The Canterbury Medical Research Foundation; The New Zealand Lottery Grants Board; The University of Otago; The Carney Centre for Pharmacogenomics; The James Hume Bequest Fund; National Institutes of Health: Genes, Environment and Health Initiative; National Institutes of Health; National Cancer Institute; The William T Grant Foundation; Australian Research Council; The Virginia Tobacco Settlement Foundation; The VISN 1 and VISN 4 Mental Illness Research, Education, and Clinical Centers of the US Department of Veterans Affairs; The 5th Framework Programme (FP-5) GenomEUtwin Project; The Lundbeck Foundation; NIH-funded Shared Instrumentation Grant S10RR025141; Clinical Translational Sciences Award grants; National Institute of Neurological Disorders and Stroke; National Heart, Lung, and Blood Institute; National Institute of General Medical Sciences.Peer reviewe

    An optimized clearing protocol for the quantitative assessment of sub-epidermal ovule tissues within whole cereal pistils

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    Background: Seed development in the angiosperms requires the production of a female gametophyte (embryo sac) within the ovule. Many aspects of female reproductive development in cereal crops are yet to be described, largely due to the technical difficulty in obtaining phenotypic information at the cellular or sub-cellular level. Hoyer’s solution is currently well established as a solution for clearing thin tissues samples, such as sections or whole tissues of bryophytes, mycorrhizal fungi, and small model organisms (e.g. Arabidopsis thaliana). Results: Here we report a Hoyer’s solution-based clearing method to facilitate clearing of the whole barley pistil, with high reproducibility. The clearing process takes 10 days from fixation to visualisation, whereupon tissue is sufficiently clear to obtain multiple phenotypic measurements from sub-epidermal tissues and cells within the ovule. Conclusion: Visualisation of cereal ovules that have not been dissected from the pistil allows an unprecedented capability to collect quantitative morphological information from the developing ovule, integument, nucellus and embryo sac. This will enable comparisons with genetic data to reveal the contribution of pre-fertilisation ovule tissues towards downstream seed development.Laura G. Wilkinson and Matthew R. Tucke

    Moral education at work: on the scope of MacIntyre’s concept of a practice

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    This paper seeks to show how MacIntyre’s concept of a practice can survive a series of ‘scope problems’ which threaten to render the concept inapplicable to business ethics. I begin by outlining MacIntyre’s concept of a practice before arguing that, despite an asymmetry between productive and non-productive practices, the elasticity of the concept of a practice allows us to accommodate productive and profitable activities. This elasticity of practices allows us to sidestep the problem of adjudicating between practitioners and non-practitioners as well as the problem of generic activities. I conclude by suggesting that the contemporary tendency to regard work as an object of consumption, rather than undermining MacIntyre’s account of practices, serves to demonstrate the potential breadth of its applicability

    Shared genetic risk between eating disorder- and substance-use-related phenotypes:Evidence from genome-wide association studies

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    First published: 16 February 202
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