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1.
The objective of this study was to evaluate the relationship of pond size and hybrid striped bass growout profitability as an alternative source of farm income in the Mid-Atlantic region. A dynamic, whole farm, Montdarlo capital budgeting simulation model (AQUASIM) and stochastic dominance with respect to a function technique were used to analyze the economics of hybrid striped bass growout from phase II to market production stage for eight farms categorized by pond sizes. Three scenarios are assumed to examine the effects of pond-size dependent changes in feed conversion efficiency and fingerling survival rates on discounted after-tax net present values and probabilities of economic survival and success. Optimal pond sizes were found to be in the 2.5 acre to 10 acre range.  相似文献   
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The role of oils in herbicide treatments is reviewed, both in terms of their own intrinsic activity and of their enhancement of the performance of other herbicides. The phytotoxicity of oils can be related to their physical properties. Their efficacy as adjuvants can vary with the plant/pesticide combination involved, and differences may also be observed between oils of mineral and vegetable origin. The possible mechanisms involved in the enhancement of activity by oils are discussed and areas of work that might elucidate these fun her are indicated.  相似文献   
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An approximately 37-yr-old female Atlantic bottlenose dolphin (Tursiops truncatus) died after a 4-mo illness characterized by intermittent anorexia, lethargy, mild neutrophilic leukocytosis, and mild nonregenerative anemia. At necropsy, the lungs were diffusely consolidated, and histopathology of the lungs revealed severe pneumonia with macrophages containing clusters of numerous yeast cells. Inflammatory lesions and yeast also were found in pulmonary, mediastinal, prescapular, and duodenal lymph nodes, spleen, liver, kidneys, urinary bladder, pancreas, right adrenal gland, and the pyloric stomach. Histomorphology, fungal culture, and polymerase chain reaction analysis indicated that the fungus was Histoplasma capsulatum var. capsulatum. This is the first report of histoplasmosis in a cetacean.  相似文献   
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Ohne Zusammenfassung Mit 5 Abbildungen.  相似文献   
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Summary Two types of processes have been applied for the pretreatment of lignocellulosic materials in order to render them easily degradable by the cellulase of Trichoderma viride. They were compared at different temperatures, with regard both to the residual dry mass and the improvement in accessibility to the enzyme complex. The latter was measured in terms of glucose liberated, which was quantified by HPLC. Hydrothermolysis proved more effective than the organosolv process for the pretreatment of wheat straw, and vice versa for poplar wood. In terms of the percentage of glucan enzymatically converted to glucose, yields up to 90% could be achieved.One of the authors (H.H.) would like to thank the Austrian Research Center Seibersdorf for granting a bursary. We are also grateful to Mr. Josef Huber for his kind assistance in preparing the three-dimensional plot  相似文献   
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The spotted-wing drosophila, Drosophila suzukii Matsumura, is an invasive pest causing significant damage to soft skinned fruits. Control of D. suzukii is critical since there is no tolerance for infested fruit in the market. While most insecticides control one or more D. suzukii life-stages (e.g., egg, larvae, and adult), the impact of insecticides that are toxic to immature stages  is unclear on the subsequent generation of a field population. Insecticides were applied at field recommended rates on cherries and blueberries in the laboratory to determine immature D. suzukii mortality. Spinetoram, cyantraniliprole, malathion, methomyl, spinosad, and phosmet resulted in relatively high mortality of all immature life stages. Zeta-cypermethrin, cyclaniliprole, and fenpropathrin resulted in lower mortality of egg and all larval instars. Malathion was also applied to lowbush blueberries with different fruit sizes (small, medium, and large) in the laboratory and there was no statistical difference in mortality rates depending on fruit sizes. Mortality data from the laboratory experiments were used to parameterize a refined D. suzukii population model. The model revealed that the timing and order of different insecticide classes are important to control D. suzukii population. Model runs that included early applications of more effective insecticides resulted in high immature mortality and greater reduction of D. suzukii populations compared to treatments applied later.

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