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Sufficient Coverage (sufficient + coverage)
Selected AbstractsEvaluation of statistical methods for left-censored environmental data with nonuniform detection limitsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2006Parikhit Sinha Abstract Monte Carlo simulations were used to evaluate statistical methods for estimating 95% upper confidence limits of mean constituent concentrations for left-censored data with nonuniform detection limits. Two primary scenarios were evaluated: data sets with 15 to 50% nondetected samples and data sets with 51 to 80% nondetected samples. Sample size and the percentage of nondetected samples were allowed to vary randomly to generate a variety of left-censored data sets. All statistical methods were evaluated for efficacy by comparing the 95% upper confidence limits for the left-censored data with the 95% upper confidence limits for the noncensored data and by determining percent coverage of the true mean (,). For data sets with 15 to 50% nondetected samples, the trimmed mean, Winsorization, Aitchison's, and log-probit regression methods were evaluated. The log-probit regression was the only method that yielded sufficient coverage (99,100%) of ,, as well as a high correlation coefficient (r2 = 0.99) and small average percent residuals (, 0.1%) between upper confidence limits for censored versus noncensored data sets. For data sets with 51 to 80% nondetected samples, a bounding method was effective (r2 = 0.96,0.99, average residual = ,5% to ,7%, 95-98% coverage of ,), except when applied to distributions with low coefficients of variation (standard deviation/, < 0.5). Thus, the following recommendations are supported by this research: data sets with 15 to 50% nondetected samples,log-probit regression method and use of Chebyshev theorem to estimate 95% upper confidence limits; data sets with 51 to 80% nondetected samples, bounding method and use of Chebyshev theorem to estimate 95% upper confidence limits. [source] Pharmacokinetics of intravenous ceftiofur sodium and concentration in body fluids of foalsJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2009S. MEYER The objectives of this study were to determine pharmacokinetics of intravenous (i.v.) ceftiofur in foals, to compare ultra-high performance liquid chromatography tandem mass spectometry (UPLC-MS/MS) and microbiologic assay for the measurement of ceftiofur concentrations, and to determine the minimum inhibitory concentration (MIC) of ceftiofur against common equine bacterial pathogens. In a cross-over design, ceftiofur sodium was administered i.v. to six foals (1,2 days-of-age and 4,5 weeks-of-age) at dosages of 5 and 10 mg/kg. Subsequently, five doses of ceftiofur were administered i.v. to six additional foals between 1 and 5 days of age at a dose of 5 mg/kg q 12 h. Concentrations of desfuroylceftiofur acetamide (DCA), the acetamide derivative of ceftiofur and desfuroylceftiofur-related metabolites were measured in plasma, synovial fluid, urine, and CSF by use of UPLC-MS/MS. A microbiologic assay was used to measure ceftiofur activity for a subset of plasma samples. Following i.v. administration of ceftiofur at a dose of 5 mg/kg to 1,2 day-old foals, DCA had a t½ of 7.8 ± 0.1 h, a body clearance of 74.4 ± 8.4 mL/h/kg, and an apparent volume of distribution of 0.83 ± 0.09 L/kg. After multiple i.v. doses at 5 mg/kg, DCA concentrations in CSF were significantly lower than concurrent plasma concentrations. Ceftiofur activity using a microbiologic assay significantly underestimated plasma concentrations of DCA. The MIC of ceftiofur required to inhibit growth of 90% of isolates of Escherichia coli, Pasteurella spp, Klebsiella spp, and ,-hemolytic streptococci was <0.5 ,g/mL. Intravenous administration of ceftiofur sodium at the rate of 5 mg/kg every 12 h would provide sufficient coverage for the treatment of susceptible bacterial isolates. [source] General competencies of problem-based learning (PBL) and non-PBL graduatesMEDICAL EDUCATION, Issue 4 2005Katinka J A H Prince Introduction, Junior doctors have reported shortcomings in their general competencies, such as organisational skills and teamwork. We explored graduates' perceptions of how well their training had prepared them for medical practice and in general competencies in particular. We compared the opinions of graduates from problem-based learning (PBL) and non-PBL schools, because PBL is supposed to enhance general competencies. Method, We analysed the responses of 1159 graduates from 1 PBL and 4 non-PBL schools to a questionnaire survey administered 18 months after graduation. Results, Compared with their non-PBL colleagues, the PBL graduates gave higher ratings for the connection between school and work, their medical training and preparation for practice. According to the graduates, the most frequently used competencies with sufficient coverage during medical training were expert knowledge, profession-specific skills and communication skills. The majority of the PBL graduates, but less than half of the non-PBL graduates, indicated that communication skills had been covered sufficiently. All the graduates called for more curriculum attention on working with computers, planning and organisation, and leadership skills. More PBL graduates than non-PBL graduates indicated that they had learned profession-specific methods, communication skills and teamwork in medical school. Discussion, Overall, the graduates appeared to be satisfied with their knowledge and skills. The results suggest that the PBL school provided better preparation with respect to several of the competencies. However, both PBL and non-PBL graduates identified deficits in their general competencies, such as working with computers and planning and organising work. These competencies should feature more prominently in undergraduate medical education. [source] Quantitative proteomics of intracellular Porphyromonas gingivalisPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 23 2007Qiangwei Xia Abstract Whole-cell quantitative proteomic analyses were conducted to investigate the change from an extracellular to intracellular lifestyle for Porphyromonas gingivalis, a Gram-negative intracellular pathogen associated with periodontal disease. Global protein abundance data for P. gingivalis strain ATCC 33277 internalized for 18,h within human gingival epithelial cells and controls exposed to gingival cell culture medium were obtained at sufficient coverage to provide strong evidence that these changes are profound. A total of 385 proteins were overexpressed in internalized P. gingivalis relative to controls; 240 proteins were shown to be underexpressed. This represented in total about 28% of the protein encoding ORFs annotated for this organism, and slightly less than half of the proteins that were observed experimentally. Production of several proteases, including the classical virulence factors RgpA, RgpB, and Kgp, was decreased. A separate validation study was carried out in which a 16-fold dilution of the P. gingivalis proteome was compared to the undiluted sample in order to assess the quantitative false negative rate (all ratios truly alternative). Truly null (no change) abundance ratios from technical replicates were used to assess the rate of quantitative false positives over the entire proteome. A global comparison between the direction of abundance change observed and previously published bioinformatic gene pair predictions for P. gingivalis will assist with future studies of P. gingivalis gene regulation and operon prediction. [source] The Northern Ireland Civil Service: Characteristics and Trends Since 1970PUBLIC ADMINISTRATION, Issue 1 2002Paul Carmichael "This is a damned funny country. There's one crowd singing ,Wrap the Green Flag Round Me' and another crowd sings ,Rule Britannia' and there's a lot of bloody civil servants up there in Stormont drawing twenty pounds a week and laughing at the lot of us."Comment made in 1939 to Patrick Shea, cited in Shea 1981, p. 205. This paper offers a summary of research on the Northern Ireland Civil Service (NICS) that has been undertaken as part of an ESRC-supported project examining the changing nature of civil services throughout the British Isles. Not since Gladden's seminal work in 1967 have studies of the British Civil Services offered sufficient coverage of the long-existing variations within the UK. The weaknesses in coverage are particularly visible with respect to the Northern Ireland Civil Service (NICS), which is accorded either footnote status in most work or even ignored altogether. A compelling case for closing the gap in the literature is underscored by the political devolution that was introduced after 1998. Far from being the unitary state associated with the Westminster model, the UK exhibits the features of a differentiated polity in which figure the contradictory impulses of centralization and fragmentation. In illustrating ,parity with particularity', the civil service arrangements obtaining within the Province of Northern Ireland clearly exemplify the differentiation with the UK. Moreover, with devolved fora now established for both Scotland and Wales, with associated pressure for more distinctive and even separate civil arrangements in each, Northern Ireland's experience offers valuable lessons on how the UK civil service may develop in Scotland and Wales. [source] | ||||||||||