303 research outputs found

    3. Launching the New Enterprise

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    As the academic year of 1945-46 approached, the intensity of activity in preparation for actually opening the school in the fall term became overwhelming. Incredible though it may seem, Ives and Day were able in a period of a few weeks to assemble the nucleus of a faculty, several of whom formed a continuing source of counsel and advice both during the school’s formative years and thereafter. Includes: The First Dean and the School’s Dedication; A Participant’s View of the Early Years; Ives Moves On; Several Views of Martin P. Catherwood; The Founders

    An assessment of abundance trends and biology of langoustines (Metanephrops mozambicus) and pink prawns (Haliporoides triarthrus) from the deep-water trawl fishery off eastern South Africa.

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    Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2013.Deep-water trawling (>200 m deep) for crustaceans in the South West Indian Ocean (SWIO) yields catches of several species, including prawns (Haliporoides triarthrus, Aristaeomorpha foliacea, Aristeus antennatus and Aristeus virilis), langoustine (Metanephrops mozambicus), spiny lobster (Palinurus delagoae) and geryonid crab (Chaceon macphersoni). Infrequent deep-water trawling takes place off Tanzania, Kenya and Madagascar; however, well-established fisheries operate off Mozambique and South Africa. Regular trawling off South Africa started in the 1970’s, mainly targeting M .mozambicus and H. triarthrus. Catch and effort data for the South African fishery were regularly recorded in skipper logbooks over a 23 year period (1988 – 2010); this database was obtained from the Department of Agriculture, Forestry and Fisheries (DAFF) in order to assess abundance trends of M. mozambicus and H. triarthrus. Generalized linear models (GLM) were used to quantify the effects of year, month, depth and vessel on catch per unit effort (CPUE). By year, the standardized CPUE of M. mozambicus increased, and three factors (or a combination of them) could explain the trend: reduced effort saturation, improved gear and technology, or an increase in abundance. By month, CPUE peaked in July and was highest between depths of 300 and 399 m. The standardized CPUE of H. triarthrus fluctuated more by year than for M. mozambicus, possibly because it is a shorter-lived and faster growing species. The monthly CPUE peaked in March, and was highest between depths of 400 and 499 m. Totals of 2 033 M. mozambicus (1 041 males and 992 females) and 5 927 H. triarthrus (2 938 males and 2 989 females) were sampled at sea between December 2010 and March 2012, during quarterly trips on-board a fishing trawler. A GLM framework was used to explore their size composition, sex ratio variability, size at maturity and reproductive cycles. Male and female M. mozambicus size distributions were similar, but varied by month and decreased as depth increased. Female H. triarthrus were significant larger than males; size structure varied by month, but showed no change over depth. The sex ratio of M. mozambicus favoured males (1 : 0.89), but was close to parity in all months, except November when males predominated. H. triarthrus exhibited parity (1 : 1.002) with no significant variations in sex ratios by month. The proportion of egg-bearing M. mozambicus in the population declined between March and August (hatching period) and then increased until December (spawning period). The L₅₀ (length at 50% maturity) of M. mozambicus was estimated to be 49.4 mm carapace length (CL), and the smallest and largest observed egg-bearing females were 33.5 and 68.6 mm, respectively. No reproductively active female H. triarthrus were recorded during the sampling period. Growth parameter estimates for M. mozambicus (male and female combined) using Fabens method were K = 0.48 yearˉ¹ and L∞ = 76.4 mm CL. Estimates for the von Bertalanffy growth formula (VBGF) were: K = 0.45 yearˉ¹ and L∞ = 76.4 mm CL. H. triarthrus male and female growth parameter were estimated separately. For males they were K = 0.5 yearˉ¹ and L∞ = 46.6 mm CL using Fabens method, and K = 0.76 yearˉ¹ and L∞ = 46.6 mm CL using the VBGF. For females they were K = 0.3 yearˉ¹ and L∞ = 62.9 mm CL using Fabens method, and K = 0.47 yearˉ¹ and L∞ = 62.9 mm CL using the VBGF. CL to total weight regressions were calculated for both species; no significant differences were found between male and female M. mozambicus, although H. triarthrus females became larger and heavier than males. Comparisons with three earlier studies (Berry, 1969; Berry et al., 1975; Tomalin et al., 1997) revealed no major changes in the biology of either species off eastern South Africa. Stocks appear to be stable at current levels of fishing pressure, although some factors are not yet fully understood. Disturbance caused by continual trawling over a spatially limited fishing ground may affect distribution and abundance patterns, especially in M. mozambicus, which was less abundant in the depth range trawled most frequently. The absence of reproductive H. triarthrus in samples suggests that they occur elsewhere, and there is some evidence of a possible spawning migration northwards to Mozambique; this suggests that H. triarthrus is a shared stock between South Africa and Mozambique. The results from this thesis will add to the knowledge of M. mozambicus and H. triarthrus in the SWIO, and provide a basis for developing sustainable management strategies for the deep-water crustacean trawl fishery off eastern South Africa

    Assessing the Feasibility of an Aerotropolis Around Cleveland Hopkins International Airport, Technical Report

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    This report provides an assessment of the feasibility of developing an aerotropolis around Cleveland Hopkins International Airport, Cleveland, Ohio. The report describes the methodology used to assess the feasibility, notes the needs and expectations of community stakeholders, profiles the challenges and successes of six emerging and potential U.S. aerotropolises, and discusses the operating experiences and challenges of 12 additional U.S. airports. Further, this report describes the demographic and economic aspects of the study cities, and discusses potential target industry opportunities. The findings suggest that it is feasible to develop CLE as an aerotropolis, and that CLE may not be suited for an aerotropolis as practiced at other domestic and international airports. Rather, the concept itself may be the platform for moving forward with a defined, staged strategy for development surrounding CLE and should be viewed as an opportunity to develop the concept to specifically fit the region and its economic circumstance

    Assessing the Feasibility of an Aerotropolis Around Cleveland Hopkins International Airport, Technical Report

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    This report provides an assessment of the feasibility of developing an aerotropolis around Cleveland Hopkins International Airport, Cleveland, Ohio. The report describes the methodology used to assess the feasibility, notes the needs and expectations of community stakeholders, profiles the challenges and successes of six emerging and potential U.S. aerotropolises, and discusses the operating experiences and challenges of 12 additional U.S. airports. Further, this report describes the demographic and economic aspects of the study cities, and discusses potential target industry opportunities. The findings suggest that it is feasible to develop CLE as an aerotropolis, and that CLE may not be suited for an aerotropolis as practiced at other domestic and international airports. Rather, the concept itself may be the platform for moving forward with a defined, staged strategy for development surrounding CLE and should be viewed as an opportunity to develop the concept to specifically fit the region and its economic circumstance

    Assessing the Feasibility of an Aerotropolis Around Cleveland Hopkins International Airport, Appendices

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    This is a companion report to the full technical report entitled, “Assessing the Feasibility of an Aerotropolis Around Cleveland Hopkins International Airport.” This report contains the supporting documents including interview scripts, focus group protocol, a reference list and glossary, cooperative economic development agreements, airport case studies, a map of physical property characteristics, and endnotes for the appendices

    Assessing the Feasibility of an Aerotropolis Around Cleveland Hopkins International Airport, Executive Report

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    This report provides an assessment of the feasibility of developing an aerotropolis around Cleveland Hopkins International Airport, Cleveland, Ohio. The report describes the methodology used to assess the feasibility, notes the needs and expectations of community stakeholders, profiles the challenges and successes of six emerging and potential U.S. aerotropolises, and discusses the operating experiences and challenges of 12 additional U.S. airports. Further, this report describes the demographic and economic aspects of the study cities, and discusses potential target industry opportunities. The findings suggest that it is feasible to develop CLE as an aerotropolis, and that CLE may not be suited for an aerotropolis as practiced at other domestic and international airports. Rather, the concept itself may be the platform for moving forward with a defined, staged strategy for development surrounding CLE and should be viewed as an opportunity to develop the concept to specifically fit the region and its economic circumstance

    Assessing the Feasibility of an Aerotropolis Around Cleveland Hopkins International Airport, Executive Report

    Get PDF
    This report provides an assessment of the feasibility of developing an aerotropolis around Cleveland Hopkins International Airport, Cleveland, Ohio. The report describes the methodology used to assess the feasibility, notes the needs and expectations of community stakeholders, profiles the challenges and successes of six emerging and potential U.S. aerotropolises, and discusses the operating experiences and challenges of 12 additional U.S. airports. Further, this report describes the demographic and economic aspects of the study cities, and discusses potential target industry opportunities. The findings suggest that it is feasible to develop CLE as an aerotropolis, and that CLE may not be suited for an aerotropolis as practiced at other domestic and international airports. Rather, the concept itself may be the platform for moving forward with a defined, staged strategy for development surrounding CLE and should be viewed as an opportunity to develop the concept to specifically fit the region and its economic circumstance

    Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead.

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    Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology

    Occurrence of microplastic pollution at oyster reefs and other coastal sites in the Mississippi sound, USA: Impacts of freshwater inflows from flooding

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    © 2020 by the authors. Much of the seafood that humans consume comes from estuaries and coastal areas where microplastics (MPs) accumulate, due in part to continual input and degradation of plastic litter from rivers and runoff. As filter feeders, oysters (Crassostrea virginica) are especially vulnerable to MP pollution. In this study, we assessed MP pollution in water at oyster reefs along the Mississippi Gulf Coast when: (1) historic flooding of the Mississippi River caused the Bonnet Carré Spillway to remain open for a record period of time causing major freshwater intrusion to the area and deleterious impacts on the species and (2) the spillway was closed, and normal salinity conditions resumed. Microplastics (~25 μm-5 mm) were isolated using a single-pot method, preparing samples in the same vessel (Mason jars) used for their collection right up until the MPs were transferred onto filters for analyses. The MPs were quantified using Nile Red fluorescence detection and identified using laser direct infrared (LDIR) analysis. Concentrations ranged from ~12 to 381 particles/L and tended to decrease at sites impacted by major freshwater intrusion. With the spillway open, average MP concentrations were positively correlated with salinity (r = 0.87, p = 0.05) for sites with three or more samples examined. However, the dilution effect on MP abundances was temporary, and oyster yields suffered from the extended periods of lower salinity. There were no significant changes in the relative distribution of MPs during freshwater intrusions; most of the MPs (\u3e50%) were in the lower size fraction (~25-90 μm) and consisted mostly of fragments (~84%), followed by fibers (~11%) and beads (~5%). The most prevalent plastic was polyester, followed by acrylates/polyurethanes, polyamide, polypropylene, polyethylene, and polyacetal. Overall, this work provides much-needed empirical data on the abundances, morphologies, and types of MPs that oysters are exposed to in the Mississippi Sound, although how much of these MPs are ingested and their impacts on the organisms deserves further scrutiny. This paper is believed to be the first major application of LDIR to the analysis of MPs in natural waters
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