Observations of the 1991 June 11 solar flare with COMPTEL

The COMPTEL instrument onboard of the Compton Gamma‐Ray Observatory (CGRO) is sensitive to γ‐rays in the energy range from 0.75 to 30 MeV and to neutrons in the energy range from 10 to 100 MeV. During the period of unexpectedly high solar activity in June 1991, several flares from active region 6659 were observed by COMPTEL. For the flare on June 11, we have analyzed the COMPTEL telescope data, finding strong 2.223 MeV line emission, that declines with a time constant of 11.8 minutes during the satellite orbit in which the flare occurs. It remains visible for at least 4 hours. We obtained preliminary values for the 2.2 MeV and 4–7 MeV fluences. Neutrons with energies above 20 MeV have been detected and their arrival time at the Earth is consistent with the γ‐ray emission during the impulsive phase

Modeling of Water Injection into a Vacuum

A loosely coupled two-phase vacuum water plume model has been developed. This model consists of a source flow model to describe the expansion of water vapor, and the Lagrangian equations of motion for particle trajectories. Gas/Particle interaction is modeled through the drag force induced by the relative velocities. Particles are assumed traveling along streamlines. The equations of motion are integrated to obtain particle velocity along the streamline. This model has been used to predict the mass flux in a 5 meter radius hemispherical domain resulting from the burst of a water jet of 1.5 mm in diameter, mass flow rate of 24.2 g/s, and stagnation pressure of 21.0 psia, which is the nominal Orbiter water dump condition. The result is compared with an empirical water plume model deduced from a video image of the STS-29 water dump. To further improve the model, work has begun to numerically simulate the bubble formation and bursting present in a liquid stream injected into a vacuum. The technique of smoothed particle hydrodynamics was used to formulate this simulation. A status and results of the on-going effort are presented and compared to results from the literature

A PDZ-Binding Motif is Essential but Not Sufficient to Localize the C Terminus of CFTR to the Apical Membrane

Localization of ion channels and transporters to the correct membrane of polarized epithelia is important for vectorial ion movement. Prior studies have shown that the cytoplasmic carboxyl terminus of the cystic fibrosis transmembrane conductance regulator (CFTR) is involved in the apical localization of this protein. Here we show that the C-terminal tail alone, or when fused to the green fluorescent protein (GFP), can localize to the apical plasma membrane, despite the absence of transmembrane domains. Co-expression of the C terminus with full-length CFTR results in redistribution of CFTR from apical to basolateral membranes, indicating that both proteins interact with the same target at the apical membrane. Amino acid substitution and deletion analysis confirms the importance of a PDZ-binding motif D-T-R-L\u3e for apical localization. However, two other C-terminal regions, encompassing amino acids 1370-1394 and 1404-1425 of human CFTR, are also required for localizing to the apical plasma membrane. Based on these results, we propose a model of polarized distribution of CFTR, which includes a mechanism of selective retention of this protein in the apical plasma membrane and stresses the requirement for other C-terminal sequences in addition to a PDZ-binding motif

Examining the potential public health benefit of offering STI testing to men in amateur football clubs: evidence from cross-sectional surveys

Background: In Britain, young people continue to bear the burden of sexually transmitted infections (STIs) so efforts are required, especially among men, to encourage STI testing. The SPORTSMART study trialled an intervention that sought to achieve this by offering chlamydia and gonorrhoea test-kits to men attending amateur football clubs between October and December 2012. With football the highest participation team sport among men in England, this paper examines the potential public health benefit of offering STI testing to men in this setting by assessing their sociodemographic characteristics, sexual behaviours, and healthcare behaviour and comparing them to men in the general population. Methods: Data were collected from 192 (male) members of 6 football clubs in London, United Kingdom, aged 18–44 years via a 20-item pen-and-paper self-completion questionnaire administered 2 weeks after the intervention. These were compared to data collected from 409 men of a similar age who were resident in London when interviewed during 2010–2012 for the third National Survey of Sexual Attitudes and Lifestyles (Natsal-3), a national probability survey that used computer-assisted-personal-interviewing with computer-assisted-self-interview. Age standardisation and multivariable regression were used to account for sociodemographic differences between the surveys. Results: Relative to men in the general population, SPORTSMART men were younger (32.8 % vs. 21.7 % aged under 25 y), and more likely to report (all past year) at least 2 sexual partners (adjusted odds ratio, AOR: 3.25, 95 % CI: 2.15–4.92), concurrent partners (AOR: 2.05, 95 % CI: 1.39–3.02), and non-use of condoms (AOR: 2.17, 95 % CI: 1.39–3.41). No difference was observed in STI/HIV risk perception (AOR for reporting “not at all at risk” of STIs: 1.25, 95 % CI: 0.76–2.04; of HIV: AOR: 1.54, 95 % CI: 0.93–2.55), nor in reporting STI testing in the past year (AOR: 0.83, 95 % CI: 0.44–1.54), which was reported by only one in six men. Conclusions: Relative to young men in the general population, football club members who completed the SPORTSMART survey reported greater sexual risk behaviour but similar STI/HIV risk perception and STI testing history. Offering STI testing in amateur football clubs may therefore widen access to STI testing and health promotion messages for men at higher STI risk, which, given the minority currently testing and the popularity of football in England, should yield both individual and public health benefit

A Composite Metric for Benchmarking Site Performance in TAVR: Results from the STS/ACC TVT Registry

Background: Transcatheter aortic valve replacement (TAVR) is a transformative therapy for aortic stenosis. Despite rapid improvements in technology and techniques, serious complications remain relatively common and are not well described by single outcome measures. The purpose of this study was to determine if there is site-level variation in TAVR outcomes in the United States using a novel 30-day composite measure. Methods: We performed a retrospective cohort study using data from the STS/ACC TVT Registry to develop a novel ranked composite performance measure that incorporates mortality and serious complications. The selection and rank order of the complications for the composite was determined by their adjusted association with 1-year outcomes. Sites whose risk-adjusted outcomes were significantly more or less frequent than the national average based on a 95% probability interval were classified as performing worse or better than expected. Results: The development cohort consisted of 52,561 patients who underwent TAVR between January 1, 2015 and December 31, 2017. Based on the associations with 1-year risk-adjusted mortality and health status, we identified four periprocedural complications to include in the composite risk model in addition to mortality. Ranked empirically according to severity, these included stroke, major, life-threatening or disabling bleeding, stage III acute kidney injury, and moderate or severe peri-valvular regurgitation. Based on these ranked outcomes, we found that there was significant site-level variation in quality of care in TAVR in the United States. Overall, better than expected site performance was observed in 25/301 (8%) of sites; performance as expected was observed in 242/301 sites (80%); and worse than expected performance was observed in 34/301 (11%) of sites. Thirty-day mortality, stroke, major, life-threatening or disabling bleeding, and moderate or severe peri-valvular leak were each substantially more common in sites with worse than expected performance as compared with other sites. There was good aggregate reliability of the model. Conclusions: There are substantial variations in the quality of TAVR care received in the United States, and 11% of sites were identified as providing care below the average level of performance. Further study is necessary to determine structural, process-related, and technical factors associated with high- and low-performing sites

Natural history of HFE simple heterozygosity for C282Y and H63D: A prospective 12-year study

Background and Aim - The risk of hemochromatosis-related morbidity for HFE simple heterozygosity for either the C282Y or H63D substitutions in the HFE protein was assessed using a prospective community-based cohort study. Methods - HFE genotypes were measured for 31 192 persons of northern European descent, aged between 40 and 69 years when recruited to the Melbourne Collaborative Cohort Study, and subjects were followed for an average of 12 years. For a random sample of 1438 participants stratified according to HFE genotype, two sets of biochemical iron indices performed 12 years apart and, at follow-up only, the presence/absence of six disease features associated with hereditary hemochromatosis were obtained. Summary data for 257 (139 female) C282Y simple heterozygotes and 123 (74 female) H63D simple heterozygotes were compared with 330 (181 female) controls with neither HFE mutation. Results - At baseline, mean transferrin saturation (TS) (95% confidence interval) and prevalence of TS > 55% were 35.14% (33.25, 37.04) and 3/112 (3%), 33.03% (29.9, 36.15) and 0/39 (0%), and 29.67% (27.93, 31.4) and 3/135 (2%) for C282Y, H63D and wild-type male participants, respectively. At follow-up, mean TS levels remained similar to baseline levels for both men and women irrespective of simple heterozygosity for either mutation. No HFE C282Y or H63D simple heterozygotes had documented iron overload (based on hepatic iron measures or serum ferritin greater than 1000 mg/L at baseline with documented therapeutic venesection). Conclusion - No documented iron overload was observed for HFE simple heterozygotes for either C282Y or H63D, and morbidity for both HFE simple heterozygote groups was similar to that of HFE wild-type participants

A pragmatic group sequential placebo controlled randomised trial to determine the effectiveness of Glyceryl trinitrate for retained placenta (GOT-IT): a study protocol

A retained placenta is diagnosed when the placenta is not delivered following delivery of the baby. It is a major cause of postpartum haemorrhage and treated by the operative procedure of manual removal of placenta (MROP).The aim of this pragmatic, randomised, placebo-controlled, double-blind UK-wide trial, with an internal pilot and nested qualitative research to adjust strategies to refine delivery of the main trial, is to determine whether sublingual glyceryl trinitrate (GTN) is (or is not) clinically and cost-effective for (medical) management of retained placenta. The primary clinical outcome is need for MROP, defined as the placenta remaining undelivered 15 min poststudy treatment and/or being required within 15 min of treatment due to safety concerns. The primary safety outcome is measured blood loss between administration of treatment and transfer to the postnatal ward or other clinical area. The primary patient-sided outcome is satisfaction with treatment and a side effect profile. The primary economic outcome is net incremental costs (or cost savings) to the National Health Service of using GTN versus standard practice. Secondary outcomes are being measured over a range of clinical and economic domains. The primary outcomes will be analysed using linear models appropriate to the distribution of each outcome. Health service costs will be compared with multiple trial outcomes in a cost-consequence analysis of GTN versus standard practice.Ethical approval has been obtained from the North-East Newcastle and North Tyneside 2 Research Ethics Committee (13/NE/0339). Dissemination plans for the trial include the Health Technology Assessment Monograph, presentation at international scientific meetings and publication in high-impact, peer-reviewed journals.ISCRTN88609453; Pre-results

The initial U.S. experience with the Tempo active fixation temporary pacing lead in structural heart interventions

ObjectivesThis multicenter retrospective study of the initial U.S. experience evaluated the safety and efficacy of temporary cardiac pacing with the Tempo® Temporary Pacing Lead.BackgroundDespite increasing use of temporary cardiac pacing with the rapid growth of structural heart procedures, temporary pacing leads have not significantly improved. The Tempo lead is a new temporary pacing lead with a soft tip intended to minimize the risk of perforation and a novel active fixation mechanism designed to enhance lead stability.MethodsData from 269 consecutive structural heart procedures were collected. Outcomes included device safety (absence of clinically significant cardiac perforation, new pericardial effusion, or sustained ventricular arrhythmia) and efficacy (clinically acceptable pacing thresholds with successful pace capture throughout the index procedure). Postprocedure practices and sustained lead performance were also analyzed.ResultsThe Tempo lead was successfully positioned in the right ventricle and achieved pacing in 264 of 269 patients (98.1%). Two patients (0.8%) experienced loss of pace capture. Procedural mean pace capture threshold (PCT) was 0.7 ± 0.8 mA. There were no clinically significant perforations, pericardial effusions, or sustained device‐related arrhythmias. The Tempo lead was left in place postprocedure in 189 patients (71.6%) for mean duration of 43.3 ± 0.7 hr (range 2.5–221.3 hr) with final PCT of 0.84 ± 1.04 mA (n = 80). Of these patients, 84.1% mobilized out of bed with no lead dislodgment.ConclusionThe Tempo lead is safe and effective for temporary cardiac pacing for structural heart procedures, provides stable peri and postprocedural pacing and allows mobilization of patients who require temporary pacing leads.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154941/1/ccd28476.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154941/2/ccd28476_am.pd

An expert-based system to predict population survival rate from health data

This work was supported by the Office of Naval Research Marine Mammal Biology Program [grant number N00014-17-1-2868].Timely detection and understanding of causes for population decline are essential for effective wildlife management and conservation. Assessing trends in population size has been the standard approach but we propose that monitoring population health could prove more effective. We collated data from seven bottlenose dolphin (Tursiops truncatus) populations in southeastern U.S. to develop the Veterinary Expert System for Outcome Prediction (VESOP), which estimates survival probability using a suite of health measures identified by experts as indices for inflammatory, metabolic, pulmonary, and neuroendocrine systems. VESOP was implemented using logistic regression within a Bayesian analysis framework, and parameters were fit using records from five of the sites that had a robust stranding network and frequent photographic identification (photo-ID) surveys to document definitive survival outcomes. We also conducted capture-mark-recapture (CMR) analyses of photo-ID data to obtain separate estimates of population survival rates for comparison with VESOP survival estimates. VESOP analyses found multiple measures of health, particularly markers of inflammation, were predictive of 1- and 2-year individual survival. The highest mortality risk one year following health assessment related to low alkaline phosphatase, with an odds ratio of 10.2 (95% CI 3.41-26.8), while 2-year mortality was most influenced by elevated globulin (9.60; 95% CI 3.88-22.4); both are markers of inflammation. The VESOP model predicted population-level survival rates that correlated with estimated survival rates from CMR analyses for the same populations (1-year Pearson's r = 0.99; p = 1.52e-05, 2-year r = 0.94; p = 0.001). While our proposed approach will not detect acute mortality threats that are largely independent of animal health, such as harmful algal blooms, it is applicable for detecting chronic health conditions that increase mortality risk. Random sampling of the population is important and advancement in remote sampling methods could facilitate more random selection of subjects, obtainment of larger sample sizes, and extension of the approach to other wildlife species.Publisher PDFPeer reviewe

A case study of controlling crossover in a selection hyper-heuristic framework using the multidimensional knapsack problem

Hyper-heuristics are high-level methodologies for solving complex problems that operate on a search space of heuristics. In a selection hyper-heuristic framework, a heuristic is chosen from an existing set of low-level heuristics and applied to the current solution to produce a new solution at each point in the search. The use of crossover low-level heuristics is possible in an increasing number of general-purpose hyper-heuristic tools such as HyFlex and Hyperion. However, little work has been undertaken to assess how best to utilise it. Since a single-point search hyper-heuristic operates on a single candidate solution, and two candidate solutions are required for crossover, a mechanism is required to control the choice of the other solution. The frameworks we propose maintain a list of potential solutions for use in crossover. We investigate the use of such lists at two conceptual levels. First, crossover is controlled at the hyper-heuristic level where no problem-specific information is required. Second, it is controlled at the problem domain level where problem-specific information is used to produce good-quality solutions to use in crossover. A number of selection hyper-heuristics are compared using these frameworks over three benchmark libraries with varying properties for an NP-hard optimisation problem: the multidimensional 0-1 knapsack problem. It is shown that allowing crossover to be managed at the domain level outperforms managing crossover at the hyper-heuristic level in this problem domain. © 2016 Massachusetts Institute of Technolog