375 research outputs found

    Copoly(Imide Siloxane) Abhesive Materials with Varied Siloxane Oligomer Length

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    Incorporation of PDMS moieties into a polyimide matrix lowered the surface energy resulting in enhanced adhesive interactions. Polyimide siloxane materials were generated using amine-terminated PDMS oligomers of different lengths to study changes in surface migration behavior, phase segregation, mechanical, thermal, and optical properties. These materials were characterized using contact angle goniometry, tensile testing, and differential scanning calorimetry. The surface migration behavior of the PDMS component depended upon the siloxane molecular weight as indicated by distinct relationships between PDMS chain length and advancing water contact angles. Similar correlations were observed for percent elongation values obtained from tensile testing, while the addition of PDMS reduced the modulus. High fidelity topographical modification via laser ablation patterning further reduced the polyimide siloxane surface energy. Initial particulate adhesion testing experiments demonstrated that polyimide siloxane materials exhibited greater abhesive interactions relative to their respective homopolyimides

    Inter-Coder Agreement for Computational Linguistics

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    This article is a survey of methods for measuring agreement among corpus annotators. It exposes the mathematics and underlying assumptions of agreement coefficients, covering Krippendorff's alpha as well as Scott's pi and Cohen's kappa; discusses the use of coefficients in several annotation tasks; and argues that weighted, alpha-like coefficients, traditionally less used than kappa-like measures in computational linguistics, may be more appropriate for many corpus annotation tasks—but that their use makes the interpretation of the value of the coefficient even harder. </jats:p

    Evidence-Based Progressive Passage to Reopening American Societies Post COVID-19

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    In the United States, the total number of confirmed reported cases of Covid-19 had reached&nbsp; 1.36 million with a total death of 80,574 and a total confirmed recoveries of 210,000 cases. Significant efforts have been invested to flatten the curve and control new cases appearing in the societies. Meanwhile, the governments has imposed a lockdown with the objective of controlling the transmission of the virus. The re-opening of societies is challenging and might involve threats, many of them remain unseen. We describe here a dynamic scenario to un-locking and re-opening societies using an evidence-based design, suggested by an algorithm of screening using RT-PCR and antibodies in a large population

    Synthesis of Long-T1 Silicon Nanoparticles for Hyperpolarized 29Si Magnetic Resonance Imaging

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    We describe the synthesis, materials characterization and dynamic nuclear polarization (DNP) of amorphous and crystalline silicon nanoparticles for use as hyperpolarized magnetic resonance imaging (MRI) agents. The particles were synthesized by means of a metathesis reaction between sodium silicide (Na4Si4) and silicon tetrachloride (SiCl4) and were surface functionalized with a variety of passivating ligands. The synthesis scheme results in particles of diameter ~10 nm with long size-adjusted 29Si spin lattice relaxation (T1) times (> 600 s), which are retained after hyperpolarization by low temperature DNP.Comment: Supporting material: https://dl.dropboxusercontent.com/u/1742676/Supporting_Atkins_v11.pd

    Life-saving automated external defibrillation in a teenager: a case report

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    <p>Abstract</p> <p>Background</p> <p>Adolescent sudden death during sport participation is commonly due to cardiac causes. Survival is more likely when an automated external defibrillator (AED) is used soon after collapse.</p> <p>Case presentation</p> <p>We describe a case of sudden death in a 14 year old boy with two remarkable points, successful resuscitation at school using an AED and diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC). Bystander cardiopulmonary resuscitation (CPR) was immediately started by a witness and 5 minutes after the event the child was placed on an AED monitor that determined he was in a non shockable rhythm, therefore CPR was continued. Two minutes later, the AED monitor detected a shockable rhythm and recommended a shock, which was then administered. One minute after the shock, a palpable pulse was detected and the child began to breathe by himself. Four days after cardiac arrest, the boy was conversing and self-caring. Cardiac magnetic resonance imaging was suggestive of ARVC.</p> <p>Conclusion</p> <p>Ventricular fibrillation secondary to ARVC may be a devastating event and places young patients and athletes at high risk of sudden death. Immediate CPR and AED have been demonstrated to be lifesaving in such events. Therefore, we suggest that schools should have teachers skilled in CPR and accessible AEDs.</p

    Human longevity is influenced by many genetic variants: evidence from 75,000 UK Biobank participants

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    This is the final version of the article. Available from the publisher via the DOI in this record.Variation in human lifespan is 20 to 30% heritable in twins but few genetic variants have been identified. We undertook a Genome Wide Association Study (GWAS) using age at death of parents of middle-aged UK Biobank participants of European decent (n=75,244 with father's and/or mother's data, excluding early deaths). Genetic risk scores for 19 phenotypes (n=777 proven variants) were also tested. In GWAS, a nicotine receptor locus(CHRNA3, previously associated with increased smoking and lung cancer) was associated with fathers' survival. Less common variants requiring further confirmation were also identified. Offspring of longer lived parents had more protective alleles for coronary artery disease, systolic blood pressure, body mass index, cholesterol and triglyceride levels, type-1 diabetes, inflammatory bowel disease and Alzheimer's disease. In candidate analyses, variants in the TOMM40/APOE locus were associated with longevity, but FOXO variants were not. Associations between extreme longevity (mother >=98 years, fathers >=95 years, n=1,339) and disease alleles were similar, with an additional association with HDL cholesterol (p=5.7x10-3). These results support a multiple protective factors model influencing lifespan and longevity (top 1% survival) in humans, with prominent roles for cardiovascular-related pathways. Several of these genetically influenced risks, including blood pressure and tobacco exposure, are potentially modifiable.This work was generously funded by an award to DM, TF, AM, LH and CB by the Medical Research Council MR/M023095/1. This research has been conducted using the UK Biobank Resource, under application 1417. The authors wish to thank the UK Biobank participants and coordinators for this unique dataset. S.E.J. is funded by the Medical Research Council (grant: MR/M005070/1). J.T. is funded by a Diabetes Research and Wellness Foundation Fellowship. R.B. is funded by the Wellcome Trust and Royal Society grant: 104150/Z/14/Z. M.A.T., M.N.W. and A.M. are supported by the Wellcome Trust Institutional Strategic Support Award (WT097835MF). R.M.F. is a Sir Henry Dale Fellow (Wellcome Trust and Royal Society grant: 104150/Z/14/Z). A.R.W. H.Y., and T.M.F. are supported by the European Research Council grant: 323195:GLUCOSEGENES-FP7-IDEAS-ERC. The funders had no influence on study design, data collection and analysis, decision to publish, or preparation of the manuscript. The Framingham Heart Study is supported by Contract No. N01-HC-25195 and HHSN268201500001I and its contract with Affymetrix, Inc for genotyping services (Contract No. N02-HL-6-4278). The phenotypegenotype association analyses were supported by National Institute of Aging R01AG29451. This work has made use of the resources provided by the University of Exeter Science Strategy and resulting Systems Biology initiative. Primarily these include high-performance computing facilities managed by Konrad Paszkiewicz of the College of Environmental and Life Sciences and Pete Leggett of the University of Exeter Academics services unit

    Communication of cancer screening results by letter, telephone or in person: A mixed methods systematic review of the effect on attendee anxiety, understanding and preferences

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    Attending and receiving a result from screening can be an anxious process. Using an appropriate method to deliver screening results could improve communication and reduce negative outcomes for screening attendees. Screening programmes are increasingly communicating results by letter or telephone rather than in-person. We investigated the impact of communication methods on attendees. We systematically reviewed the literature on the communication methods used to deliver results in cancer screening programmes for women, focusing on screening attendee anxiety, understanding of results and preferences for results communication. We included qualitative and quantitative research. We searched MEDLINE, PsycINFO, CINAHL, Cochrane Library and Embase. Results were analysed using framework synthesis. 10,558 papers were identified with seven studies meeting the inclusion criteria. Several key ideas emerged from the synthesis including speed, accuracy of results, visual support, ability to ask questions, privacy of results location and managing expectations. Verbal communication methods (telephone and in-person) were preferred and facilitated greater understanding than written methods, although there was considerable variability in attendee preferences. Findings for anxiety were mixed, with no clear consensus on which method of communication might minimise attendee anxiety. The low number of identified studies and generally low quality evidence suggest we do not know the most appropriate communication methods in the delivery of cancer screening results. More research is needed to directly compare methods of results communication, focusing on what impact each method may have on screening attendees
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