1,035 research outputs found

    BAYESIAN ESTIMATION FOR THE M/G/1 QUEUE USING A PHASE TYPE APPROXIMATION

    Get PDF
    This article deals with Bayesian inference and prediction for M/G/1 queueing systems. The general service time density is approximated with a class of Erlang mixtures which are phase type distributions. Given this phase type approximation, an explicit evaluation of measures such as the stationary queue size, waiting time and busy period distributions can be obtained. Given arrival and service data, a Bayesian procedure based on reversible jump Markov Chain Monte Carlo methods is proposed to estimate system parameters and predictive distributions.

    Philosophy, Science and Social Science

    Get PDF
    Philosophy, Science and Social Scienc

    Lasting temperature effects on the muscle tissue, body growth and fillet texture of adult turbots, Scophthalmus maximus, L.

    Get PDF
    In the teleosts, several factors can influence the muscle growth patterns of fish by a modulation of the hypertrophy and hyperplasia. The temperature (T) is one of the most important environmental factors. Thus, the T history of fish influences on their potential growth, as it has been observed in Salmon, Salmo salar (Johnston et al., 2003) and other species. The T imprinting can influence on the muscle cellularity throughout the advanced stages of life due to the lasting T effects on myogenic cells precursors (MPC) (Steinbacher et al., 2011). In different teleost species, a correlation between texture and muscle fibre size has been demonstrated (Hatae et al., 1990). Hence, the thermal history can also influence in the flesh texture. In the present work we study the lasting T effects in adult turbots reared at different Ts during the early phases. This species reaches ≈ 1.5 kg at 18-20 months of age and the first sexual maturity takes place at ≈ 24 month

    Amino acid stable N isotope estimations reveal uniform diazotrophic contributions across zooplankton size fractions in the subtropical N Atlantic

    Get PDF
    presentacionNatural abundance of stable N isotopes (d15N) in both individual amino acids and bulk organic matter of size-fractionated plankton samples were compared to analyze the differential impact of nitrogen fixation through the food web, in a transect across the subtropical North Atlantic. Low d15N values in the central and western regions were consistent with the prevalence of nitrogen fixation, while maximum d15N values tracked the influence of West African upwelling in the eastern zone. Compound-specific amino acid isotope data (CSI-AA) revealed relatively low variability in the impact of diazotrophic nitrogen within the different plankton size fractions, while d15N of bulk organic matter showed higher variability with size. Moreover, CSI-AA results also indicated a greater importance of diazotrophy than suggested by bulk d15N values. Trophic position estimates using CSI-AA showed the expected general increase with mean plankton size class and varied in a relatively narrow range (1.8 to 2.5), with the lowest values in the central zone. Using isotopic δ15N values of individual amino acids (in particular Phe and Thr), as well as reconstructed total protein d15N values, a set of new relationships with bulk plankton d15N was determined, aimed to improve the use CSI-AA data in tracing direct plankton contributions to organic nitrogen pools in the ocean. These new results represent the most detailed investigation of CSI-AA data in zooplankton size classes to date, and point to a key role of large zooplankton in the transmission of the diazotrophic nitrogen up oceanic food webs.Malaspina-2010(CSD2008-00077), NSF Grant OCE-113181

    U-Pb zircon geochronology of intrusive rocks from an exotic block in the Late Cretaceous – Paleocene Taraklı Flysch (northern Turkey): Constraints on the tectonics of the Intrapontide suture zone

    Get PDF
    In the Boyal\u131 area (northern Anatolia), a thick succession of the Early Maastrichtian - Middle Paleocene Tarakl\u131 Flysch crops out. The Tarakl\u131 Flysch represents a foredeep sediment deposited during the final stage of collision between the Sakarya and Istanbul-Zonguldak continental margins, that developed as a consequence of the closure of the Intrapontide oceanic basin. The top of the Tarakl\u131 Flysch is characterized by a level of slide-block in shaly-matrix lithofacies that can be considered as the result of several fast catastrophic events predating the closure of the basin and its deformation. This level consists of slide-blocks surrounded by monomict pebbly-mudstones and pebbly-sandstones. Among the slide-blocks, the biggest one consists of quartz-monzonites and leucocratic granodiorites of Late Permian age (260.8 \ub1 2.2 Ma) dated by zircon LA-ICP-MS method. By comparison with the regional data, the source area of these granitoids can be identified in the Istanbul-Zonguldak terrane. This evidence suggests a new picture for the paleogeographic setting of the ultimate stage of the continental collision between the Istanbul-Zonguldak and the Sakarya continental margins. In this scenario the coarse-grained deposits of the Tarakl\u131 Flysch are supplied by an orogenic wedge, consisting of oceanic units topped by the Istanbul-Zonguldak terrane. This orogenic wedge represented the north side of the foredeep, while the southern one was represented by the still undeformed Sakarya continental margin

    Avaliação do curso de Engenharia de Ordenamento dos Recursos Naturais

    Get PDF
    O relatório resulta do trabalho de avaliação ao curso de Engenharia de Ordenamento dos Recursos Naturais levado a cabo pela equipa de Auto-Avaliação da Escola Superior Agrária. Esta equipa, designada pelo Conselho Científico com a finalidade de proceder a todas as solicitações de avaliação tanto dos cursos como da instituição, é basicamente composta por um coordenador e um elemento de cada unidade departamental. Decorrente do tipo de curso que se está a avaliar juntam-se à equipa os respectivos coordenadores do curso e um relator. Além deste elementos participaram também neste trabalho um representante dos alunos (designado pela associação de estudantes) e dois funcionários representantes do pessoal administrativo e do pessoal não docente. Em termos metodológicos optou-se pelo seguimento do guião proposto pelo CNAVES, tendo-se recolhido informação de diversos modos: pesquisa documental e bases de dados nos serviços administrativos, inquéritos auto administrados a alunos, docentes e funcionários, inquérito postal aos diplomados e entrevistas directas às entidades empregadoras. Uma vez recolhida e tratada a informação procedeu-se à sua análise crítica tendo como referência os trabalhos de avaliação que até então decorreram relativamente à Escola e ao curso de Ordenamento dos Recursos Naturais

    Spanish adaptation of the Stroke and Aphasia Quality of Life Scale-39 (SAQOL-39)

    Get PDF
    [Abstract] Aim. The stroke and aphasia quality of life scale-39 is an interviewer administered questionnaire that has been developed and validated in the United Kingdom to be applied to patients with chronic aphasia as a consequence of a stroke. The objective of this article was to translate the Stroke and Aphasia Quality of Life-39 Scale (SAQOL-39) into Spanish language, and evaluate its acceptability and reliability. Methods. The cross-cultural adaptation of the SAQOL- 39 into Spanish was carried out by following the translation and back-translation method. Twenty three patients with long-term aphasia due to stroke were tested. The patients were interviewed twice in a period from 2 to 12 days. The acceptability of the Spanish SAQOL- 39 was evaluated by examining the floor/ceiling effects and the missing data. The reliability was assessed by Cronbach’s alpha (internal consistence) and intraclass correlation coefficients (test-retest reliability) for the overall scale and its subdomains. Results. There were no difficulties to translate the original version into Spanish. There was good acceptability demonstrated by minimal missing data and floor/ceiling effects. Test-retest reliability for the overall score, and the subscales scores was 0.949 (0.854-0.944). Internal consistency analysis by Cronbach’s α was 0.950 (0.851-0.900). Conclusion. This small scale study provided preliminary evidence for the acceptability and reliability of the Spanish version of the SAQOL-39. Further testing in larger samples is needed to evaluate the validity of the scale, its sensitivity to change and to confirm its reliability
    • …
    corecore