953 research outputs found
Concentration of Selected Priority Organic Contaminants in Fish Maintained on Formulated Diets in Lake Ontario Waters
Fish were grown in Lake Ontario water under conditions simulating commercial aquaculture and then analyzed for 10 priority organic contaminants. Black bullheads (Ameiurus meias) were grown in cages placed in a bay of Lake Ontario. Rainbow trout (Oncorhynchus mykiss) were grown in terrestrial raceways served with Lake Ontario water. Yearlings were reared on a commercial ration in these systems, which partially isolated them from the contaminant-laden food web and bottom sediments, to an average weight of 93 g for black bullheads (range, 31-220 g) and 213 g (29-558 g) for rainbow trout. Concentrations of contaminants in skinless fillets of both rainbow trout cultivated 6 months and black bullheads cultured 3.5 months in Lake Ontario waters were nondetectable or less than one-sixth the action levels defined by the U.S. Food and Drug Administration. Contaminant levels in rainbow trout were consistently less than concentrations observed in black bullheads. Of the 10 priority contaminants surveyed, 7 were nondetectable in rainbow trout and 3 were nondetectable in black bullheads. Concentrations of contaminants in both species were generally much lower than levels observed in wild fish from Lake Ontario. This investigation demonstrated that bioaccumulation of lipophilic contaminants by fish cultured under simulated commercial conditions in Lake Ontario was not significant. These findings have implications for commercial aquaculture, regulatory decisions, and fish consumers in the Great Lakes basin and elsewhere
Parasitic Copepods of Chinook, Oncorhynchus tshawytscha (Walbaum), and Coho, Oncorhynchus kisutch (Walbaum), Salmon of Lake Michigan
Uptake and Retention of Mirex By Fish Maintained on Formulated and Natural Diets in Lake Ontario Waters
Fish with no detectable levels of the contaminant mirex were grown in Lake Ontario waters under conditions simulating commercial aquaculture. Benthic black bullheads (Ameiurus me/as) were grown in cages placed in a bay of the lake. Pelagic rainbow trout (Oncorhynchus mykiss) were grown in terrestrial raceways served with Lake Ontario waters. Contaminant-free fingerlings were reared to a large size on a commercial ration in these systems, which partially isolated them from the contaminant-laden food web and bottom sediments. Black bullheads fed a mirex-spiked, commercially prepared food had mirex concentrations that exceeded the U.S. Food and Drug Administration (FDA) action level of 0.1 p,g/g, significantly higher than concen, trations in fish receiving the same commercial food without mirex. Ninety percent offish receiving the unspiked ration had nondetectable levels of mirex (values below 0.002 p,g/g). The 10% containing mirex had concentrations 94% below FDA action level. In the rainbow trout study, 97% of the fish had no detectable levels ofmirex. This investigation demonstrated that bioaccumulation of the lipophilic contaminant mirex by fish cultured under simulated commercial conditions in Lake Ontario waters was not significant. These findings have implications for commercial aquaculture, regulatory decisions, and health-conscious fish consumers in the Great Lakes Basin
Phytoplankton, Zooplankton, Macrobenthos and lchthyoplankton Abundance, Biomass and Species Composition in Onondaga Lake, 1994
Once a pristine recreational center and a productive fishery that supplied New York City markets with fresh fish, Onondaga Lake is now considered one of the most badly degraded bodies of water in the entire world (Sage 1993). The Onondaga Lake Management Conference was established to develop a comprehensive restoration, conservation, and management plan for Onondaga Lake that recommends priority corrective actions and a compliance schedule for cleanup of the lake. Biological assessment of the lake has been infrequent and concentrated on a few biological groups. This study either updates or establishes baseline characteristics for the following biological components of the Onondaga Lake ecosystem: phytoplankton, zooplankton, ichthyoplankton and macrobenthos
Infection Prevention and the Protective Effects of Unidirectional Displacement Flow Ventilation in the Turbulent Spaces of the Operating Room
Background: Unidirectional displacement flow (UDF) ventilation systems in operating rooms are characterized by a uniformity of velocity 80% and protect patients and operating room personnel against exposure to hazardous substances. However, the air below the surgical lights and in the surrounding zone is turbulent, which impairs the ventilation system’s effect.
Aim: We first used the recovery time (RT) as specified in International Organization for Standardization 14644 to determine the particle reduction capacity in the turbulent spaces of an operating room with a UDF system. Methods: The uniformity of velocity was analyzed by comfort-level probe grid measurements in the protected area below a hemispherical closed-shaped and a semi-open column-shaped surgical light (tilt angles: 0/15/30) and in the surrounding zone of a research operating room. Thereafter, RTs were calculated.
Results: At a supply air volume of 10,500 m3/h, the velocity, reported as average uniformity+standard deviation, was uniform in the protected area without lights (95.8% + 1.7%), but locally turbulent below the hemispherical closedshaped (69.3% + 14.6%), the semi-open column-shaped light (66.9% + 10.9%), and in the surrounding zone (51.5%+17.6%). The RTs ranged between 1.1 and 1.7 min below the lights and 3.5+0.28 min in the surrounding zone and depended exponentially on the volume flow rate.
Conclusions: Compared to an RT of 20 min as required for operating rooms with mixed dilution flow, particles here were eliminated 12–18 times more quickly from below the surgical lights and 5.7 times from the surrounding zone. Thus, the effect of the lights was negligible and the UDF’s retained its strong protective effect
Is Entrepreneurial Success Predictable? An Ex-Ante Analysis of the Character-Based Approach
This paper empirically analyzes whether the character-based approach, which focuses on the personality structure and the human capital of business founders, allows prediction of entrepreneurial success. A unique data set is used consisting of 414 persons whose personal characteristics were analyzed by different methods, namely an one-day assessment center (AC) and a standardized questionnaire, before they launched their business. Results are partly unexpected and weaker than previous ex-post findings: first, we found correlations between the AC data and the questionnaire in one subgroup only. Second, the predictive power of the AC data is slightly better than that of the questionnaire, but lower than expected in theory. Interestingly, for those subgroups where the AC data have low predictive power, the questionnaire does better. Third, when success is measured in terms of employees hired, the character-based approach is a poor predictor. Copyright 2008 The Authors.
Predictors of outcome for severely emotionally disturbed children in treatment
Despite general agreement that severely emotionally disturbed children and adolescents are an "at risk" group, and that ongoing evaluation and research into the effectiveness of services provided for them is important, very little outcome evaluation actually takes place. The absence of well-conducted and appropriately interpreted studies is particularly notable for day or residential treatment programs, which cater for the most severely emotionally disturbed youths. This thesis outlines the main areas of conceptual, pragmatic and methodological confusion and neglect which impede progress in research in this area. It argues for plurality of data analytic strategies and research designs. It then critically reviews the reported findings about the effectiveness of day and residential treatment in specialist facilities, and the predictors of good outcomes for this treatment type. This review confirms that there is very little to guide practice. Having argued for the legitimacy of its methods and the necessity to address basic questions, the thesis reports the results of a naturalistic study based on data accumulated during a decade-long evaluative research program taking place at Arndell Child and Adolescent Unit, Sydney. The study addresses the question of what child, family and treatment variables predict outcome for 159 children and adolescents treated at this facility from 1990 to 1999. Statistically significant results with large effect size were obtained. Among the most disturbed subgroup of forty three children, (a) psychodynamic milieu-based treatment was shown to be more effective than the “empirically-validated” cognitive-behavioural treatment which superseded it in 1996, and (b) children from step-families showed better outcome than those from other family structures. Furthermore, it was found for the study sample as a whole that severe school-based problem behaviours were associated with a limited trajectory of improvement in home-based problem behaviour. These results are discussed with regard to implications for treatment, research methodology, policy and further studies
Proporción diaria de alimento del diablillo antártico (pleuragramma antarcticum boulenger, 1902) en el este del mar de weddell
[EN] The daily ration of Pleuragramma antarcticum in the Eastern Weddell Sea was investigated from midwater and bottom trawl samples collected in the Antarctic in the summer of 1998. Using a gastric evacuation model that takes into account Weddell Sea temperature below zero and information on the prey type daily ration estimates were: 1.133% BW for immature fish of 10-16 cm and 0.484% BW for mature fish of 17-24 cm. The low daily ration intake was influenced by the low temperatures that limited the rate of gastric evacuation. This model seems more realistic than results from the classic Elliot & Persson and Eggers models that are also used in this paper, since their assumptions on feeding regularity are more rigid and they do not consider data of energy density of the prey[ES] La ración diaria de alimento de Pleuragramma antarcticum en el mar de Weddell es investigada en muestras de arrastres de fondo y pelágicas recogidas durante diferentes horas del día en el verano antártico de 1998. Utilizando un modelo de evacuación gástrica que tiene en cuenta la temperatura bajo del Mar de Weddell e información sobre el tipo de presa, las estimaciones de consumo diario fueron: 1.133% BW para peces inmaduros entre 10 -16 cm y 0.484% BW para peces maduros entre 17-24 cm. La baja ración diaria ingerida estuvo influida por las bajas temperaturas que limitan la tasa de evacuación gástrica. Este modelo parece más realista que los resultados de los modelos clásicos de Elliot & Persson and Eggers también empleados, ya que sus asunciones sobre su periodicidad de alimentación son más rígidas y no consideran datos de densidad energética de las presasThis work was conducted under the SCAR EASIZ programme, and was supported by the Alfred Wegener Institute and the Spanish Antarctic ProgrammePeer reviewe
Large scale cosmic-ray anisotropy with KASCADE
The results of an analysis of the large scale anisotropy of cosmic rays in
the PeV range are presented. The Rayleigh formalism is applied to the right
ascension distribution of extensive air showers measured by the KASCADE
experiment.The data set contains about 10^8 extensive air showers in the energy
range from 0.7 to 6 PeV. No hints for anisotropy are visible in the right
ascension distributions in this energy range. This accounts for all showers as
well as for subsets containing showers induced by predominantly light
respectively heavy primary particles. Upper flux limits for Rayleigh amplitudes
are determined to be between 10^-3 at 0.7 PeV and 10^-2 at 6 PeV primary
energy.Comment: accepted by The Astrophysical Journa
Onboard Hydrogen/Helium Sensors in Support of the Global Technical Regulation: An Assessment of Performance in Fuel Cell Electric Vehicle Crash Tests
Automobile manufacturers in North America, Europe, and Asia project a 2015 release of commercial hydrogen fuel cell powered light-duty road vehicles. These vehicles will be for general consumer applications, albeit initially in select markets but with much broader market penetration expected by 2025. To assure international harmony, North American, European, and Asian regulatory representatives are striving to base respective national regulations on an international safety standard, the Global Technical Regulation (GTR), Hydrogen Fueled Vehicle, which is part of an international agreement pertaining to wheeled vehicles and equipment for wheeled vehicles
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