865 research outputs found

    The prediction of thriving in elite sport:A prospective examination of the role of psychological need satisfaction, challenge appraisal, and salivary biomarkers

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    ObjectivesTo examine (i) whether levels of, and changes in, athletes’ basic psychological need satisfaction (BPNS) and challenge appraisals predicted in-match thriving; and (ii) if salivary biomarkers could be defined that were related to thriving.DesignProspective study design.MethodsFifty-one elite male hockey players ( M age = 24.94 years, SD age = 4.73) completed questionnaires measuring their BPNS and challenge appraisals on seven consecutive days prior to a competitive match, as well as providing saliva samples immediately on waking, and then +0.5, +3, and +5.25 h on the day of the match. Saliva was assayed for catabolic (i.e., cortisol) and anabolic (i.e., dehydroepiandrosterone [DHEA]) hormones. In-match thriving was assessed retrospectively using measures of subjective performance and well-being.ResultsLatent growth curve modelling showed pre-match levels of BPNS and challenge appraisals to positively predict thriving. Although not statistically significant, small and moderate negative associations were found for thriving with cortisol concentration (+5.25 h sample) and total cortisol exposure across the morning of the match, respectively. DHEA concentration shared a small positive, yet non-significant, association with thriving.ConclusionsAthletes’ pre-match levels of BPNS and challenge appraisal predict in-match thriving; thus, offering potential mechanisms through which both high-level performance and the experience of well-being can be facilitated. Furthermore, associations suggest that total cortisol exposure across the morning of the match, and cortisol and DHEA levels in pre-match samples may offer sport science and sports medicine practitioners potential biomarkers for thriving. Future research is required to substantiate this initial finding.<br/

    Experimental and Theoretical (e,2e) Ionization Cross Sections for a Hydrogen Target at 75.3 eV Incident Energy in a Coplanar Asymmetric Geometry

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    Very recently it was shown that the molecular three-body distorted wave (M3DW) approach gives good agreement with the shape of the experimental data for electron-impact ionization of H2 in a coplanar symmetric geometry, providing the incident electrons have an energy of 35 eV or greater. One of the weaknesses of these studies was that only the shape of the cross section could be compared to experiment, since there was no absolute or relative normalization of the data. Here we report a joint experimental/theoretical study of electron-impact ionization of H2 in a coplanar asymmetric geometry where the energy of the incident electron was fixed, and different pairs of final state electron energies were used. In this case, the experimental data can be normalized such that only one renormalization factor is required. It is shown that the M3DW is pretty good in agreement with experiment. However, a better treatment of polarization and exchange between the continuum and bound state electrons is required before quantitative agreement between experiment and theory is achieved

    Rapid diagnostic test for antenatal syphilis screening in low-income and middle-income countries: a systematic review and meta-analysis

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    OBJECTIVES: To undertake a systematic review and meta-analysis to evaluate the test performance including sensitivity and specificity of rapid immunochromatographic syphilis (ICS) point-of-care (POC) tests at antenatal clinics compared with reference standard tests (non-treponemal (TP) and TP tests) for active syphilis in pregnant women. METHODS: Five electronic databases were searched (PubMed, EMBASE, CRD, Cochrane Library and LILACS) to March 2016 for diagnostic accuracy studies of ICS test and standard reference tests for syphilis in pregnant women. Methodological quality was assessed using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies). A bivariate meta-analysis was undertaken to generate pooled estimates of diagnostic parameters. Results were presented using a coupled forest plot of sensitivity and specificity and a scatter plot. RESULTS: The methodological quality of the five included studies with regards to risk of bias and applicability concern judgements was either low or unclear. One study was judged as high risk of bias for patient selection due to exclusion of pregnant women with a previous history of syphilis, and one study was judged at high risk of bias for study flow and timing as not all patients were included in the analysis. Five studies contributed to the meta-analysis, providing a pooled sensitivity and specificity for ICS of 0.85 (95% CrI: 0.73 to 0.92) and 0.98 (95% CrI: 0.95 to 0.99), respectively. CONCLUSIONS: This review and meta-analysis observed that rapid ICS POC tests have a high sensitivity and specificity when performed in pregnant women at antenatal clinics. However, the methodological quality of the existing evidence base should be taken into consideration when interpreting these results. PROSPERO REGISTRATION NUMBER: CRD42016036335

    Shaping electron wave functions in a carbon nanotube with a parallel magnetic field

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    A magnetic field, through its vector potential, usually causes measurable changes in the electron wave function only in the direction transverse to the field. Here we demonstrate experimentally and theoretically that in carbon nanotube quantum dots, combining cylindrical topology and bipartite hexagonal lattice, a magnetic field along the nanotube axis impacts also the longitudinal profile of the electronic states. With the high (up to 17T) magnetic fields in our experiment the wave functions can be tuned all the way from "half-wave resonator" shape, with nodes at both ends, to "quarter-wave resonator" shape, with an antinode at one end. This in turn causes a distinct dependence of the conductance on the magnetic field. Our results demonstrate a new strategy for the control of wave functions using magnetic fields in quantum systems with nontrivial lattice and topology.Comment: 5 figure

    A novel accelerometer-based method to describe day-to-day exposure to potentially osteogenic vertical impacts in older adults: findings from a multi-cohort study

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    Summary: This observational study assessed vertical impacts experienced in older adults as part of their day-to-day physical activity using accelerometry and questionnaire data. Population-based older adults experienced very limited high-impact activity. The accelerometry method utilised appeared to be valid based on comparisons between different cohorts and with self-reported activity. Introduction: We aimed to validate a novel method for evaluating day-to-day higher impact weight-bearing physical activity (PA) in older adults, thought to be important in protecting against osteoporosis, by comparing results between four cohorts varying in age and activity levels, and with self-reported PA levels. Methods: Participants were from three population-based cohorts, MRC National Survey of Health and Development (NSHD), Hertfordshire Cohort Study (HCS) and Cohort for Skeletal Health in Bristol and Avon (COSHIBA), and the Master Athlete Cohort (MAC). Y-axis peaks (reflecting the vertical when an individual is upright) from a triaxial accelerometer (sampling frequency 50 Hz, range 0–16 g) worn at the waist for 7 days were classified as low (0.5–1.0 g), medium (1.0–1.5 g) or higher (≥1.5 g) impacts. Results: There were a median of 90, 41 and 39 higher impacts/week in NSHD (age 69.5), COSHIBA (age 76.8) and HCS (age 78.5) participants, respectively (total n = 1512). In contrast, MAC participants (age 68.5) had a median of 14,322 higher impacts/week. In the three population cohorts combined, based on comparison of beta coefficients, moderate-high-impact activities as assessed by PA questionnaire were suggestive of stronger association with higher impacts from accelerometers (0.25 [0.17, 0.34]), compared with medium (0.18 [0.09, 0.27]) and low impacts (0.13 [0.07,0.19]) (beta coefficient, with 95 % CI). Likewise in MAC, reported moderate-high-impact activities showed a stronger association with higher impacts (0.26 [0.14, 0.37]), compared with medium (0.14 [0.05, 0.22]) and low impacts (0.03 [−0.02, 0.08]). Conclusions: Our new accelerometer method appears to provide valid measures of higher vertical impacts in older adults. Results obtained from the three population-based cohorts indicate that older adults generally experience very limited higher impact weight-bearing PA

    Infliximab, adalimumab and golimumab for treating moderately to severely active ulcerative colitis after the failure of conventional therapy (including a review of TA140 and TA262): clinical effectiveness systematic review and economic model.

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    BACKGROUND: Ulcerative colitis (UC) is the most common form of inflammatory bowel disease in the UK. UC can have a considerable impact on patients' quality of life. The burden for the NHS is substantial. OBJECTIVES: To evaluate the clinical effectiveness and safety of interventions, to evaluate the incremental cost-effectiveness of all interventions and comparators (including medical and surgical options), to estimate the expected net budget impact of each intervention, and to identify key research priorities. DATA SOURCES: Peer-reviewed publications, European Public Assessment Reports and manufacturers' submissions. The following databases were searched from inception to December 2013 for clinical effectiveness searches and from inception to January 2014 for cost-effectiveness searches for published and unpublished research evidence: MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature, The Cochrane Library including the Cochrane Systematic Reviews Database, Cochrane Controlled Trials Register, Database of Abstracts of Reviews of Effects, the Health Technology Assessment database and NHS Economic Evaluation Database; ISI Web of Science, including Science Citation Index, and the Conference Proceedings Citation Index-Science and Bioscience Information Service Previews. The US Food and Drug Administration website and the European Medicines Agency website were also searched, as were research registers, conference proceedings and key journals. REVIEW METHODS: A systematic review [including network meta-analysis (NMA)] was conducted to evaluate the clinical effectiveness and safety of named interventions. The health economic analysis included a review of published economic evaluations and the development of a de novo model. RESULTS: Ten randomised controlled trials were included in the systematic review. The trials suggest that adult patients receiving infliximab (IFX) [Remicade(®), Merck Sharp & Dohme Ltd (MSD)], adalimumab (ADA) (Humira(®), AbbVie) or golimumab (GOL) (Simponi(®), MSD) were more likely to achieve clinical response and remission than those receiving placebo (PBO). Hospitalisation data were limited, but suggested more favourable outcomes for ADA- and IFX-treated patients. Data on the use of surgical intervention were sparse, with a potential benefit for intervention-treated patients. Data were available from one trial to support the use of IFX in paediatric patients. Safety issues identified included serious infections, malignancies and administration site reactions. Based on the NMA, in the induction phase, all biological treatments were associated with statistically significant beneficial effects relative to PBO, with the greatest effect associated with IFX. For patients in response following induction, all treatments except ADA and GOL 100 mg at 32-52 weeks were associated with beneficial effects when compared with PBO, although these were not significant. The greatest effects at 8-32 and 32-52 weeks were associated with 100 mg of GOL and 5 mg/kg of IFX, respectively. For patients in remission following induction, all treatments except ADA at 8-32 weeks and GOL 50 mg at 32-52 weeks were associated with beneficial effects when compared with PBO, although only the effect of ADA at 32-52 weeks was significant. The greatest effects were associated with GOL (at 8-32 weeks) and ADA (at 32-52 weeks). The economic analysis suggests that colectomy is expected to dominate drug therapies, but for some patients, colectomy may not be considered acceptable. In circumstances in which only drug options are considered, IFX and GOL are expected to be ruled out because of dominance, while the incremental cost-effectiveness ratio for ADA versus conventional treatment is approximately £50,300 per QALY gained. LIMITATIONS: The health economic model is subject to several limitations: uncertainty associated with extrapolating trial data over a lifetime horizon, the model does not consider explicit sequential pathways of non-biological treatments, and evidence relating to complications of colectomy was identified through consideration of approaches used within previous models rather than a full systematic review. CONCLUSIONS: Adult patients receiving IFX, ADA or GOL were more likely to achieve clinical response and remission than those receiving PBO. Further data are required to conclusively demonstrate the effect of interventions on hospitalisation and surgical outcomes. The economic analysis indicates that colectomy is expected to dominate medical treatments for moderate to severe UC. STUDY REGISTRATION: This study is registered as PROSPERO CRD42013006883. FUNDING: The National Institute for Health Research Health Technology Assessment programme

    Surgical interventions for treating extracapsular hip fractures in older adults: a network meta‐analysis: Review

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    Background Hip fractures are a major healthcare problem, presenting a challenge and burden to individuals and healthcare systems. The number of hip fractures globally is rising. The majority of extracapsular hip fractures are treated surgically. Objectives To assess the relative effects (benefits and harms) of all surgical treatments used in the management of extracapsular hip fractures in older adults, using a network meta‐analysis of randomised trials, and to generate a hierarchy of interventions according to their outcomes. Search methods We searched CENTRAL, MEDLINE, Embase, Web of Science and five other databases in July 2020. Selection criteria We included randomised controlled trials (RCTs) and quasi‐RCTs comparing different treatments for fragility extracapsular hip fractures in older adults. We included internal and external fixation, arthroplasties and non‐operative treatment. We excluded studies of hip fractures with specific pathologies other than osteoporosis or resulting from high‐energy trauma. Data collection and analysis Two review authors independently assessed studies for inclusion. One review author completed data extraction which was checked by a second review author. We collected data for three outcomes at different time points: mortality and health‐related quality of life (HRQoL) ‐ both reported within 4 months, at 12 months and after 24 months of surgery, and unplanned return to theatre (at end of study follow‐up). We performed a network meta‐analysis (NMA) with Stata software, using frequentist methods, and calculated the differences between treatments using risk ratios (RRs) and standardised mean differences (SMDs) and their corresponding 95% confidence intervals (CIs). We also performed direct comparisons using the same codes. Main results We included 184 studies (160 RCTs and 24 quasi‐RCTs) with 26,073 participants with 26,086 extracapsular hip fractures in the review. The mean age in most studies ranged from 60 to 93 years, and 69% were women. After discussion with clinical experts, we selected nine nodes that represented the best balance between clinical plausibility and efficiency of the networks: fixed angle plate (dynamic and static), cephalomedullary nail (short and long), condylocephalic nail, external fixation, hemiarthroplasty, total hip arthroplasty (THA) and non‐operative treatment. Seventy‐three studies (with 11,126 participants) with data for at least two of these treatments contributed to the NMA. We selected the dynamic fixed angle plate as a reference treatment against which other treatments were compared. This was a common treatment in the networks, providing a clinically appropriate comparison. We downgraded the certainty of the evidence for serious and very serious risks of bias, and because some of the estimates included the possibility of transitivity owing to the proportion of stable and unstable fractures between treatment comparisons. We also downgraded if we noted evidence of inconsistency in direct or indirect estimates from which the network estimate was derived. Most estimates included the possibility of benefits and harms, and we downgraded the evidence for these treatments for imprecision. Overall, 20.2% of participants who received the reference treatment had died by 12 months after surgery. We noted no evidence of any differences in mortality at this time point between the treatments compared. Effect estimates of all treatments included plausible benefits as well as harms. Short cephalomedullary nails had the narrowest confidence interval (CI), with 7 fewer deaths (26 fewer to 15 more) per 1000 participants, compared to the reference treatment (risk ratio (RR) 0.97, 95% CI 0.87 to 1.07). THA had the widest CI, with 62 fewer deaths (177 fewer to 610 more) per 1000 participants, compared to the reference treatment (RR 0.69, 95% CI 0.12 to 4.03). The certainty of the evidence for all treatments was low to very low. Although we ranked the treatments, this ranking should be interpreted cautiously because of the imprecision in all the network estimates for these treatments. Overall, 4.3% of participants who received the reference treatment had unplanned return to theatre. Compared to this treatment, we found very low‐certainty evidence that 58 more participants (14 to 137 more) per 1000 participants returned to theatre if they were treated with a static fixed angle plate (RR 2.48, 95% CI 1.36 to 4.50), and 91 more participants (37 to 182 more) per 1000 participants returned to theatre if treated with a condylocephalic nail (RR 3.33, 95% CI 1.95 to 5.68). We also found that these treatments were ranked as having the highest probability of unplanned return to theatre. In the remaining treatments, we noted no evidence of any differences in unplanned return to theatre, with effect estimates including benefits as well as harms. The certainty of the evidence for these other treatments ranged from low to very low. We did not use GRADE to assess the certainty of the evidence for early mortality, but our findings were similar to those for 12‐month mortality, with no evidence of any differences in treatments when compared to dynamic fixed angle plate. Very few studies reported HRQoL and we were unable to build networks from these studies and perform network meta‐analysis. Authors' conclusions Across the networks, we found that there was considerable variability in the ranking of each treatment such that there was no one outstanding, or subset of outstanding, superior treatments. However, static implants such as condylocephalic nails and static fixed angle plates did yield a higher risk of unplanned return to theatre. We had insufficient evidence to determine the effects of any treatments on HRQoL, and this review includes data for only two outcomes. More detailed pairwise comparisons of some of the included treatments are reported in other Cochrane Reviews in this series. Short cephalomedullary nails versus dynamic fixed angle plates contributed the most evidence to each network, and our findings indicate that there may be no difference between these treatments. These data included people with both stable and unstable extracapsular fractures. At this time, there are too few studies to draw any conclusions regarding the benefits or harms of arthroplasty or external fixation for extracapsular fracture in older adults. Future research could focus on the benefits and harms of arthroplasty interventions compared with internal fixation using a dynamic implant

    Comparison of two modern vaccines and previous influenza infection against challenge with an equine influenza virus from the Australian 2007 outbreak

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    During 2007, large outbreaks of equine influenza (EI) caused by Florida sublineage Clade 1 viruses affected horse populations in Japan and Australia. The likely protection that would be provided by two modern vaccines commercially available in the European Union (an ISCOM-based and a canarypox-based vaccine) at the time of the outbreaks was determined. Vaccinated ponies were challenged with a representative outbreak isolate (A/eq/Sydney/2888-8/07) and levels of protection were compared. A group of ponies infected 18 months previously with a phylogenetically-related isolate from 2003 (A/eq/South Africa/4/03) was also challenged with the 2007 outbreak virus. After experimental infection with A/eq/Sydney/2888-8/07, unvaccinated control ponies all showed clinical signs of infection together with virus shedding. Protection achieved by both vaccination or long-term immunity induced by previous exposure to equine influenza virus (EIV) was characterised by minor signs of disease and reduced virus shedding when compared with unvaccinated control ponies. The three different methods of virus titration in embryonated hens’ eggs, EIV NP-ELISA and quantitative RT-PCR were used to monitor EIV shedding and results were compared. Though the majority of previously infected ponies had low antibody levels at the time of challenge, they demonstrated good clinical protection and limited virus shedding. In summary, we demonstrate that vaccination with current EIV vaccines would partially protect against infection with A/eq/Sydney/2888-8/07-like strains and would help to limit the spread of disease in our vaccinated horse population
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