123 research outputs found

    Operational, water quality and temporal factors affecting impingement of fish and shellfish at a Texas coastal power plant

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    AbstractThe Barney M. Davis Power Plant in Corpus Christi, Texas, withdraws large quantities of water from the Laguna Madre for non-contact cooling. As a result, fish and shellfish may be harmed when impinged against screens intended to remove debris and wrack (floating sea grass). To reduce impingement it is important to understand related factors and their interrelationships. Several operational, water quality, and temporal factors were correlated with the total number of impinged organisms when the plant is pumping water. In this study, operational factors included hourly average flow and the number of screens in operation during sampling. Water quality factors included temperature, dissolved oxygen, pH, conductivity and salinity. Temporal factors included month and time of day of impingement sampling. Over the course of a year, fish and shellfish impinged on Passavant traveling drum screens were collected, classified, and counted. Multiple regression analyses were conducted and the number of organisms impinged was the response variable. Total impingement was most associated with dissolved oxygen concentration, sampling month and sampling time. For fish, sampling month and dissolved oxygen were most associated with impingement, while for shellfish, sampling month and sampling time were most important. Hourly flow and number of operating screens were not significant predictors of impingement

    To the question of the distribution and diagnosis of typhoid and typhus in the military field conditions (based on the materials of the Great Patriotic War)

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    The article analyzes the problems of diagnostics of typhoid and typhus during the Great Patriotic War. The main difficulties in diagnosing these diseases in military conditions and the ways to overcome them are highlightedВ статье проанализированы проблемы диагностики брюшного и сыпного тифа во время Великой Отечественной войны. Освещены основные трудности диагностики данных заболеваний в военных условиях и пути их преодолени

    Non-syndromic Hearing Impairment in a Hungarian Family with the m.7510T>C Mutation of Mitochondrial tRNA^^Ser(UCN)^^^ and Review of Published Cases

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    The m.7510T>C mitochondrial DNA (mtDNA) mutation is a tRNA(Ser(UCN)) alteration leading to matrilineal isolated hearing impairment. The current paper reviews the available reports on the m.7510T>C mtDNA mutation, with special attention to phenotypic variations and haplogroup background. A Hungarian family, the fourth family reported in the literature, is presented, in which analysis of three generations with bilateral isolated hearing loss revealed the m.7510T>C tRNA(Ser(UCN)) mutation in homoplasmic form in the affected members. Haplogroup analysis verified an unnamed subgroup of mitochondrial haplogroup H. Previously reported Spanish and North American Caucasian families belong to different subgroups of haplogroup H. Analyzing our biobank of Hungarian patients with sensorineural hearing loss, we did not detect this mutation in any other patient, nor was it found in Caucasian haplogroup H control samples. Comparing the cases reported so far, there is interfamilial variablity in the age of onset, accompanying symptoms, and haplogroup background. Our case adds further genetic evidence for the pathogenicity of the m.7510T>C mutation and underlines the need to include full mtDNA sequencing in the screening for unexplained hearing loss

    Quality gap of educational services in viewpoints of students in Hormozgan University of medical sciences

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    <p>Abstract</p> <p>Background</p> <p>Higher education is growing fast and every day it becomes more and more exposed to globalization processes. The aim of this study was to determine the quality gap of educational services by using a modified SERVQUAL instrument among students in Hormozgan University of Medical Sciences.</p> <p>Methods</p> <p>A cross-sectional study was carried out at Hormozgan University of Medical Sciences in 2007. In this study, a total of 300 students were selected randomly and asked to complete a questionnaire that was designed according to SERVQUAL methods. This questionnaire measured students' perceptions and expectations in five dimensions of service that consists of assurance, responsiveness, empathy, reliability and tangibles. The quality gap of educational services was determined based on differences between students' perceptions and expectations.</p> <p>Results</p> <p>The results demonstrated that in each of the five SERVQUAL dimensions, there was a negative quality gap. The least and the most negative quality gap means were in the reliability (-0.71) and responsiveness (-1.14) dimensions respectively. Also, there were significant differences between perceptions and expectations of students in all of the five SERVQUAL dimensions (p < 0.001).</p> <p>Conclusion</p> <p>Negative quality gaps mean students' expectations exceed their perceptions. Thus, improvements are needed across all five dimensions.</p

    Structure of benthic communities in small rivers of southern Sakhalin in summer-autumn period, a case of the Lyutoga River tributaries

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    Quantitative characteristics of microbial community, algal periphyton and macrozoobenthos are presented for two tributaries of the Lyutoga River, as the Partizanka River (pink salmon spawning stream) and the Frikena River (without steady spawning grounds), on the base of surveys conducted in July-October, 2011. Number of benthic bacteria in the bottom grounds varied in the range 1.1-4.0 · 106 cells/g in the Frikena and 0.8-11.1 · 106 cells/g in the Partizanka. Oligocarbophilic microorganisms prevailed in the bacterial benthos of both rivers before the beginning of active salmon spawning (July- August), developing mainly on autochthonous organic substrates. In September, with appearance of salmon carcasses after spawning, total abundance of the microorganisms increased and the portion of ammonifying bacteria basing on this allochthonous organic matter became higher in the Partizanka. Algal periphyton biomass changed from 7.8 to 117.0 g/m2 in the Frikena River and from 0.5 to 305.6 g/m2 in the Partizanka River, with diatoms domination in both streams. Periphyton in the Partizanka was destroyed by flood in September but successively recovered by October, with multiple increasing of the algal biomass, obviously due to influx of nutrients in the process of salmon carcasses decomposing. Biomass of macrozoobenthos was 5.1-21.0 g/m2 in the Frikena River and 2.2 to 3.7 g/m2 in the Partizanka River, in both tributaries its dynamics was determined mainly by life cycles of aquatic insects

    Galactic chemical abundance evolution in the solar neighborhood up to the Iron peak

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    We have developed a detailed standard chemical evolution model to study the evolution of all the chemical elements up to the iron peak in the solar vicinity. We consider that the Galaxy was formed through two episodes of exponentially decreasing infall, out of extragalactic gas. In a first infall episode, with a duration of \sim 1 Gyr, the halo and the thick disk were assembled out of primordial gas, while the thin disk formed in a second episode of infall of slightly enriched extragalactic gas, with much longer timescale. The model nicely reproduces the main observational constraints of the solar neighborhood, and the calculated elemental abundances at the time of the solar birth are in excellent agreement with the solar abundances. By the inclusion of metallicity dependent yields for the whole range of stellar masses we follow the evolution of 76 isotopes of all the chemical elements between hydrogen and zinc. Those results are confronted with a large and recent body of observational data, and we discuss in detail the implications for stellar nucleosynthesis.Comment: 19 pages, 14 figures, submitted to A&
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