5,966 research outputs found

    A sequential direct arylation/Suzuki-Miyaura cross-coupling transformation of unprotected 2 '-deoxyadenosine affords a novel class of fluorescent analogues

    Get PDF
    Novel rigid 8-biaryl-2'-deoxyadenosines with tuneable fluorescent properties can be accessed by an efficient sequential catalytic Pd-0-coupling approach

    ‘I guess it’s kind of elitist’: the formation and mobilisation of cultural, social and physical capital in youth sport volunteering

    Get PDF
    Policy and research portray sport volunteering as a means by which young people can develop skills and perform active citizenship. This paper draws on qualitative research with participants in a UK sport volunteering programme to critically examine young people’s volunteering journeys and how these are shaped by their formation and mobilisation of capital. The results show how programme structures and practices, such as selection criteria, privilege young people with higher levels of cultural and physical capital, and afford these youth additional opportunities to accumulate and mobilise cultural and social capital. The paper argues for a more critical understanding of youth sport volunteering; one that recognises that sport volunteering can reserve the practice of active citizenship for privileged youth

    Are methodological quality and completeness of reporting associated with citation-based measures of publication impact? A secondary analysis of a systematic review of dementia biomarker studies

    Get PDF
    Objective: To determine whether methodological and reporting quality are associated with surrogate measures of publication impact in the field of dementia biomarker studies. Methods: We assessed dementia biomarker studies included in a previous systematic review in terms of methodological and reporting quality using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) and Standards for Reporting of Diagnostic Accuracy (STARD), respectively. We extracted additional study and journal-related data from each publication to account for factors shown to be associated with impact in previous research. We explored associations between potential determinants and measures of publication impact in univariable and stepwise multivariable linear regression analyses. Outcome measures: We aimed to collect data on four measures of publication impact: two traditional measures—average number of citations per year and 5-year impact factor of the publishing journal and two alternative measures—the Altmetric Attention Score and counts of electronic downloads. Results: The systematic review included 142 studies. Due to limited data, Altmetric Attention Scores and electronic downloads were excluded from the analysis, leaving traditional metrics as the only analysed outcome measures. We found no relationship between QUADAS and traditional metrics. Citation rates were independently associated with 5-year journal impact factor (β=0.42; p<0.001), journal subject area (β=0.39; p<0.001), number of years since publication (β=-0.29; p<0.001) and STARD (β=0.13; p<0.05). Independent determinants of 5-year journal impact factor were citation rates (β=0.45; p<0.001), statement on conflict of interest (β=0.22; p<0.01) and baseline sample size (β=0.15; p<0.05). Conclusions: Citation rates and 5-year journal impact factor appear to measure different dimensions of impact. Citation rates were weakly associated with completeness of reporting, while neither traditional metric was related to methodological rigour. Our results suggest that high publication usage and journal outlet is not a guarantee of quality and readers should critically appraise all papers regardless of presumed impact

    ECP divisional training: plan 1996

    Get PDF
    The divisional training plan is produced each year at the request of the Joint Training Board (JTB) following a recommendation in the 1991 CERN Training Plan which states that divisions should produce a plan setting out training priorities. This plan presents a review of training activities. a report on ECP progress in implementing the recommendations of the 1995 CERN training plan, a discussion of divisional training objectives, and a summary of training requests generated by the 1996 periodic interview exercise

    Shubnikov de Haas effect in the metallic state of Na0.3_{0.3}CoO2_2

    Full text link
    Shubnikov de Haas oscillations for two well defined frequencies, corresponding respectively to areas of 0.8 and 1.36% of the first Brillouin zone (FBZ), were observed in single crystals of Na0.3_{0.3}CoO2_2. The existence of Na superstructures in Na0.3_{0.3}CoO2_2, coupled with this observation, suggests the possibility that the periods are due to the reconstruction of the large Fermi surface around the Γ\Gamma point. An alternative interpretation in terms of the long sought-after ϵg\epsilon_g^\prime pockets is also considered but found to be incompatible with existing specific heat data.Comment: 5 pages 4 figure

    Endogenous glucagon-like peptide 1 controls endocrine pancreatic secretion and antro-pyloro-duodenal motility in humans

    Get PDF
    Background: Exogenous use of the intestinal hormone glucagon-like peptide 1 (GLP-1) lowers glycaemia by stimulation of insulin, inhibition of glucagon, and delay of gastric emptying.Aims: To assess the effects of endogenous GLP-1 on endocrine pancreatic secretion and antro-pyloro-duodenal motility by utilising the GLP-1 receptor antagonist exendin(9-39)amide (ex(9-39)NH2).Methods: Nine healthy volunteers underwent four experiments each. In two experiments with and without intravenous infusion of ex(9-39)NH2 300 pmol/kg/min, a fasting period was followed by intraduodenal glucose perfusion at 1 and 2.5 kcal/min, with the higher dose stimulating GLP-1 release. Antro-pyloro-duodenal motility was measured by perfusion manometry. To calculate the incretin effect (that is, the proportion of plasma insulin stimulated by intestinal hormones) the glycaemia observed during the luminal glucose experiments was mimicked using intravenous glucose in two further experiments.Results: Ex(9-39)NH2 significantly increased glycaemia during fasting and duodenal glucose. It diminished plasma insulin during duodenal glucose and significantly reduced the incretin effect by approximately 50%. Ex(9-39)NH2 raised plasma glucagon during fasting and abolished the decrease in glucagon at the high duodenal glucose load. Ex(9-39)NH2 markedly stimulated antroduodenal contractility. At low duodenal glucose it reduced the stimulation of tonic and phasic pyloric motility. At the high duodenal glucose load it abolished pyloric stimulation.Conclusions: Endogenous GLP-1 stimulates postprandial insulin release. The pancreatic \textgreeka cell is under the tonic inhibitory control of GLP-1 thereby suppressing postprandial glucagon. GLP-1 tonically inhibits antroduodenal motility and mediates the postprandial inhibition of antral and stimulation of pyloric motility. We therefore suggest GLP-1 as a true incretin hormone and enterogastrone in humans
    corecore