2,635 research outputs found

    Population characteristics and biology of striped marlin, Tetrapturus audax in the New Zealand fishery : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science (MSc) in Physiology at Massey University, Palmerston North, New Zealand

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    Striped marlin (Tetrapturus audax) are apex predators in the pelagic ecosystem and are seasonally abundant in the off-shore waters of New Zealand during December through May. Data presented in this thesis were derived from a variety of fishing databases from New Zealand, Australia and United States as well as biological samples collected from east Northland New Zealand. This thesis may be used to help answer questions about growth and size structure, factors influencing conventional tag recoveries, and the trophic dynamics of striped marlin in the New Zealand fishery. Results show that the average weight of striped marlin in the New Zealand recreational fishery has declined between 1925-1944 (117.9 ± 0.6 kg) and 1985-2003 (96.6 ± 0.3 kg) (Means ± S.E.). The root causes of this average size decline are unknown but appear to be related to the expansion of a surface longline fishery in the southwest Pacific Ocean during 1958. Despite the large average size (104.9 ± 0.2 kg) of striped marlin from New Zealand, parameters estimated in the von Bertalanffy growth model (L∞3010 mm, K=0.22 annual and t 0=-0.04) do not show higher growth rates compared to Hawaii or Mexico. During their residency in the New Zealand Exclusive Economic Zone (EEZ) the condition Wr (relative weight) of striped marlin improves from 95.1 ± 1.2 to 109.4 ± 3.4 and average weight increases from 98.1 ± 2.0 kg to 114.6 = 0.4 kg. These data imply that striped marlin migrate to New Zealand in order to take advantage of the abundant food resources and to improve condition after spawning in warmer waters to the north. Arrow squid (Nototodarus spp.), jack mackerel (Trachurus murphyi) and saury (Scomberesox saurus) comprised a large portion of the diet from (n=20) striped marlin stomachs during March of 2004. Additionally, with a consumption rate of 0.962 to 1.28 kg of prey per day, striped marlin may consume the equivalent of 2.8-3.5% of New Zealand's current commercial catch of arrow squid and jack mackerel respectively. With concerns about declining pelagic fish stocks, tag-and-recovery programmes have become increasingly popular and over 50% of recreationally captured marlin in New Zealand are tagged and released annually. However, low tag recovery rates (<1.0%) have hindered progress in understanding growth, stock structure and migration patterns important for managing this species. Data from this study suggests that tag returns from striped marlin would increase if more fish were captured and released in less than 39 min and a greater number of small (< 89 kg) individuals were released. Tag recoveries and presumably post-release survivorship of striped marlin was reduced by increasing capture time and fish size. Rates of injury were lowest during capture times ranging from 20-29 min and in fish weighing 60-89 kg

    Investigation of optimization of attitude control systems, volume ii

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    Attitude control system optimization - computer programs, listings and subroutine

    Investigation of optimization of attitude control systems, volume i

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    Optimization of attitude control systems by development of mathematical model and computer program for space vehicle simulatio

    Forschungsschiff METEOR Reise Nr. 66 (2005) SUBFLUX

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    Centrifugation and capillarity integrated into a multiple analyte whole blood analyser

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    A unique clinical chemistry analyser is described which processes 90 μl of whole blood (fingerstick or venous) into multiple aliquots of diluted plasma and reports the results of 12 tests in 14 min. To perform a panel of tests, the operator applies the unmetered sample directly into a single use, 8 cm diameter plastic rotor which contains the required liquid diluent and dry reagents. Using centrifugal and capillary forces, the rotor meters the required amount of blood, separates the red cells, meters the plasma, meters the diluent, mixes the fluids, distributes the fluid to the reaction cuvettes and mixes the reagents and the diluted plasma in the cuvettes. The instrument monitors the reagent reactions simultaneously using nine wavelengths, calculates the results from the absorbance data, and reports the results

    Toward a Social Practice Theory of Relational Competing

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    This paper brings together the competitive dynamics and strategy-aspractice literatures to investigate relational competition. Drawing on a global ethnography of the reinsurance market, we develop the concept of micro-competitions, which are the focus of competitors’ everyday competitive practices. We find variation in relational or rivalrous competition by individual competitors across the phases of a micro-competition, between competitors within a micro-competition, and across multiple micro-competitions. These variations arise from the interplay between the unfolding competitive arena and the implementation of each firm’s strategic portfolio. We develop a conceptual framework that makes four contributions to: relational competition; reconceptualizing action and response; elaborating on the awareness-motivation-capability framework within competitive dynamics; and the recursive dynamic by which implementing strategy inside firms shapes, and is shaped by, the competitive arena

    Spin density matrix of the ω in the reaction p¯p→ωπ0

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    The spin density matrix of the ω has been determined for the reaction p¯p→ωπ0 with unpolarized in-flight data measured by the Crystal Barrel LEAR experiment at CERN. The two main decay modes of the ω into π0γ and π+π-π0 have been separately analyzed for various p¯ momenta between 600 and 1940 MeV/c. The results obtained with the usual method by extracting the matrix elements via the ω decay angular distributions and with the more sophisticated method via a full partial wave analysis are in good agreement. A strong spin alignment of the ω is clearly visible in this energy regime and all individual spin density matrix elements exhibit an oscillatory dependence on the production angle. In addition, the largest contributing orbital angular momentum of the p¯p system has been identified for the different beam momenta. It increases from Lp¯pmax = 2 at 600 MeV/c to Lp¯pmax = 5 at 1940 MeV/c
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