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1.
Appl Radiat Isot ; 157: 109033, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32063328

RESUMO

Alternate treatment routes for radioactive waste are a key research area for much of the nuclear industry, with potentially significant savings available through volume reduction of waste. Achieving this requires a full and demonstrable understanding of waste product behaviour. For this purpose, the UK's National Nuclear Laboratory (NNL) has been collaborating with the University of Glasgow and Lynkeos Technology to develop passive techniques for analysis of waste containers over a number of years. In this instance, novel muon tomographic techniques have been applied to the analysis of thermally treated nuclear waste surrogates as part of a project to build and deploy a first of a kind muon imaging system for nuclear waste. The system has been deployed at NNL's Central Laboratory, Cumbria, UK, to analyse products from a series of thermal treatment technology trials, funded by the Nuclear Decommissioning Authority (NDA) through the Direct Research Portfolio (DRP). Analysis of the waste products using this technique has proven the value of muon analysis in the development of waste management technologies, proving an ability to understand the homogeneity of products and direct further destructive testing. Results from three different thermal treatment trials are presented, with three different surrogate intermediate level waste (ILW) forms in each.


Assuntos
Mésons , Resíduos Radioativos/análise , Tomografia Computadorizada por Raios X/métodos , Gerenciamento de Resíduos/métodos
2.
Acad Emerg Med ; 20(10): 997-1003, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24127702

RESUMO

BACKGROUND: Hirsch's h-index (h) attempts to measure the combined academic impact and productivity of a scientist by counting the number of publications by an author, ranked in descending order by number of citations, until the paper number equals the number of citations. This approach provides a natural number or index of the number of publications and the number of citations per publication. H was first described in physics and was demonstrated to be highly predictive of continued academic activity, including recognized measures of scientific excellence such as membership in the National Academy of Sciences and being a Nobel laureate. Citation rates, research environments, and years of experience all affect h, making any comparisons appropriate only for scientists working in the same field for a similar time period. The authors are unaware of any report describing the distribution of h among academic emergency physicians (AEPs). OBJECTIVES: The objective was to describe the distribution of h for AEPs and to determine whether Hirsch's demonstration of the h-index as a predictor of continued scholarly activity among physicists would also apply to AEPs. METHODS: Academic EPs were identified from lists provided on allopathic U.S. emergency medicine (EM) residency program websites. "Harzing's Publish or Perish," a free program available on the Web that queries Google Scholar, was used to calculate h for each AEP. Agreement between raters was analyzed on a subset of 100 EPs. An analysis of the 20 EPs with the top h-indices was performed to characterize the entire body of their scholarly work, and their h-indices were calculated at 12 and 24 years into their careers. RESULTS: A total of 4,744 AEPs from 136 programs were evaluated. Nine programs did not publicly list the faculty at their institutions and were excluded. A linear weighted kappa was used to measure rater concordance, with agreement of 98.3% and κ = 0.92 (95% confidence interval [CI] = 0.861 to 0.957). The majority of AEPs had h-indices of zero or one (59%), 85% had h-indices less than six, 95% less than 13, and 99% less than 24. Ten percent of AEPs had h/(years in publication) of 0.5 or greater. For the top 20 EPs, the mean (± standard deviation [±SD]) h-index increased from 7.6 (±4.6) to 23.5 (±9.4) between years 12 and 24. The mean (±SD) increase in h-index was 15.8 (±7.6). CONCLUSIONS: The h-index can be used to characterize the academic productivity of AEPs. An h/year of 0.5 or greater is characteristic of the most productive EPs and represents only 10% of all AEPs. The 12-year h-index of top-performing EPs was strongly related to their future academic productivity. The distribution of h among EPs may provide a means for individual investigators and academic leaders to evaluate performance and identify EPs with future success in EM research.


Assuntos
Bibliometria , Medicina de Emergência/estatística & dados numéricos , Médicos/estatística & dados numéricos , Centros Médicos Acadêmicos/estatística & dados numéricos , Estudos Transversais , Eficiência , Humanos , Internato e Residência/estatística & dados numéricos , Publicações/estatística & dados numéricos , Estados Unidos
3.
Diab Vasc Dis Res ; 9(2): 138-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22234950

RESUMO

Guidelines recommend aggressive goals for lipid and blood pressure reduction for high risk patients with diabetes mellitus and atherosclerotic coronary disease. However, it remains unclear how many patients achieve treatment goals versus the number of people merely placed on treatment. We conducted an observational study in an academic cardiology clinic. A total of 926 patients with atherosclerotic cardiovascular disease and concomitant diabetes mellitus met criteria. Mean age was 68.4 ± 10.2, 65.6% were male, and 86.8% were Caucasian. By the last visit a high percentage of patients were receiving recommended medications. Mean LDL-cholesterol achieved was 80.4 mg/dl with 40.9% reaching ≤ 70 mg/dl, and 61.7% reaching SBP ≤ 130 mmHg. Many patients with diabetes mellitus and atherosclerotic cardiovascular disease are prescribed recommended medications; however, few achieve guidelines-specified therapeutic goals for LDL-cholesterol and blood pressure. Studies evaluating performance improvement should include percentage of patients reaching treatment goals. Mechanisms underlying the treatment gap need to be identified and addressed.


Assuntos
Aterosclerose/tratamento farmacológico , LDL-Colesterol/sangue , Doença da Artéria Coronariana/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Hipolipemiantes/uso terapêutico , Padrões de Prática Médica , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Aterosclerose/sangue , Aterosclerose/epidemiologia , Aterosclerose/fisiopatologia , Biomarcadores/sangue , Pressão Sanguínea/efeitos dos fármacos , Distribuição de Qui-Quadrado , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , Estudos Transversais , Medicina Baseada em Evidências , Feminino , Fidelidade a Diretrizes , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
4.
Ann Emerg Med ; 59(2): 103-11, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21872969

RESUMO

STUDY OBJECTIVE: Automated external defibrillators are essential for treatment of cardiac arrest by lay rescuers and must determine when to shock and if they are functioning correctly. We seek to characterize automated external defibrillator failures reported to the Food and Drug Administration (FDA) and whether battery failures are properly detected by automated external defibrillators. METHODS: FDA adverse event reports are catalogued in the Manufacturer and User Device Experience (MAUDE) database. We developed and internally validated an instrument for analyzing MAUDE data, reviewing all reports in which a fatality occurred. Two trained reviewers independently analyzed each report, and a third resolved discrepancies or passed them to a committee for resolution. RESULTS: One thousand two hundred eighty-four adverse events were reported between June 1993 and October 2008, of which 1,150 were failed defibrillation attempts. Thirty-seven automated external defibrillators never powered on, 252 failed to complete rhythm analysis, and 524 failed to deliver a recommended shock. In 149 cases, the operator disagreed with the device's rhythm analysis. In 54 cases, the defibrillator stated the batteries were low and in 110 other instances powered off unexpectedly. Interrater agreement between reviewers 1 and 2 ranged by question from 69.0% to 98.6% and for most likely cause was 55.9%. Agreement was obtained for 93.7% to 99.6% of questions by the third reviewer. Remaining discrepancies were resolved by the arbitration committee. CONCLUSION: MAUDE information is often incomplete and frequently no corroborating data are available. Some conditions not detected by automated external defibrillators during self-test cause units to power off unexpectedly, causing defibrillation delays. Backup units frequently provide shocks to patients.


Assuntos
Desfibriladores/efeitos adversos , Análise de Falha de Equipamento , Bases de Dados Factuais , Fontes de Energia Elétrica/efeitos adversos , Fontes de Energia Elétrica/estatística & dados numéricos , Análise de Falha de Equipamento/estatística & dados numéricos , Humanos , Estudos Retrospectivos , Estados Unidos , United States Food and Drug Administration
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