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Fisheries management in most areas of the world is concerned with the effects of resource exploitation on the broad marine environment that includes all major ecological components. However, all fisheries lack some information about many of these components particularly marine habitats and non-target species. Such data deficiencies make it difficult to identify priorities for management action. Qualitative ecological risk assessment is one tool that can be used by management to prioritise and evaluate management strategies. This paper demonstrates the mechanics of a qualitative ecological risk assessment applied to a currently operating data deficient commercial fishery. In particular, we demonstrate how the method applies to two distinct ecological components – marine habitats and harvested species – and shows how it contributed to the formation of management responses. The method combines biological and ecological information about each component with knowledge on the operations of the fishery. Using pre-defined decision rules and criteria the available information is used in a rigorous, transparent and repeatable manner. The paper demonstrates that the method can be used generally to apply to all ecological components of a marine fishery where data is deficient.  相似文献   
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Anticoagulant poisoning is a common rodent control method in urban areas, but rodents may exhibit versatile feeding behavioural habits in varying environmental conditions. This study has been conducted to determine those environmental factors that could directly influence bait consumption and which therefore may affect an urban rodent control plan carried out with chemical methods. In the city of Bologna (Italy), 2500 bait stations have been monitored in various urban biotopes and the bait consumption studied in relation to several environmental factors, using both bivariate and multivariate analysis. Results reveal that the rodent patch distribution triggers the avoidance of baits placed outside of their home-range, hence the importance on bait placement. The logistic regression model confirms that vegetation, harbourage and water supplies are important variables in determining bait consumption, probably because they may spatially and temporarily facilitate the agoraphobic rodent movement, ensuring undisturbed bait consumption. The role of predators (dogs and cats) and food competitors (synanthropic birds) remains insignificant. However, bait eating invertebrates may consume part of the bait. For a proper rodent control plan the first real need is to minimize the alternative food sources, which may compete with baits. Weather conditions in which rodents could possibly pass unnoticed (fog and rainfall) may encourage bait consumption, vice versa with a cold climate. The considered environmental factors have satisfactorily explained bait consumption, highlighting the importance of human influence. The study of environmental factors may be useful in categorizing several site-specific conditions where rodent control efforts should be targeted, enhancing any intervention by matching the correct and specific strategy.  相似文献   
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Because solar energy is available in large excess relative to current rates of energy consumption, effective conversion of this renewable yet intermittent resource into a transportable and dispatchable chemical fuel may ensure the goal of a sustainable energy future. However, low conversion efficiencies, particularly with CO(2) reduction, as well as utilization of precious materials have limited the practical generation of solar fuels. By using a solar cavity-receiver reactor, we combined the oxygen uptake and release capacity of cerium oxide and facile catalysis at elevated temperatures to thermochemically dissociate CO(2) and H(2)O, yielding CO and H(2), respectively. Stable and rapid generation of fuel was demonstrated over 500 cycles. Solar-to-fuel efficiencies of 0.7 to 0.8% were achieved and shown to be largely limited by the system scale and design rather than by chemistry.  相似文献   
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Journal of Crop Science and Biotechnology - This study aims to elucidate the molecular characterization of Trichoderma strains isolated from rice soil rhizosphere from paddy cultivation in West...  相似文献   
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Journal of Crop Science and Biotechnology - A correction to this paper has been published: https://doi.org/10.1007/s12892-021-00097-2  相似文献   
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The determination of the geographical origin of dairy products is an ongoing issue. In this paper the effects of botanical diversity of two pastures on the hydrocarbon and fatty acid composition of cheese fat were studied, over 2 years of experimentation. Two areas in the Italian southwestern Alpine region, dominated by Trifolium alpinum (T) and Festuca nigrescens (F) vegetation, respectively, were chosen, and milk obtained from cows grazing on these pastures was used to produce a semihard traditional cheese. Cheese samples showed a significantly different composition of most linear hydrocarbons, odd-chain (C15, C17, and C17:1) and unsaturated (trans-11,cis-15-C18:2, C18:3, C20:4n-6, C20:4n-3, and 20:5n-3) fatty acids, according to pasture type. The ratio between C(29) and C(27) linear hydrocarbons, unlike the absolute content of the single molecules, showed a good discriminating ability between the two pastures and was little affected by the natural variability due to the climatic and environmental factors.  相似文献   
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Neospora caninum is widely distributed in the world and this parasite is one of the major causes of abortion in cattle. Dogs and coyotes are definitive hosts of N. caninum and several species of domestic and wild animals are intermediate hosts. Dogs can become infected by the ingestion of tissues containing cysts and then excrete oocysts. It is not yet known whether sporulated oocysts are able to induce a patent infection in dogs, i.e. a shedding of N. caninum oocysts in feces. The objective of this study was to experimentally examine the infection of dogs by sporulated oocysts. The oocysts used in the experiment were obtained by feeding dogs with brain of buffaloes (Bubalus bubalis) positive for anti-N. caninum antibodies by indirect fluorescent antibody test (IFAT ≥200). Oocysts shed by these dogs were confirmed to be N. caninum by molecular methods and by bioassay in gerbils, and sporulated N. caninum oocysts were used for the oral infection of four dogs. The dogs were 8 weeks old and negative for antibodies to N. caninum and Toxoplasma gondii. Dogs 1 and 4 received an inoculum of 10,000 sporulated oocysts each; dog 2 an inoculum of 5000 sporulated oocysts and dog 3 received 1000 sporulated oocysts of N. caninum. The total feces excreted by these dogs were collected and examined daily for a period of 30 days. No oocysts were found in their feces. The dogs were monitored monthly for a 6-month period to observe a possible seroconversion and when this occurred the animals were eliminated from the experiment. Dogs 1 and 4 seroconverted 1 month after the infection with titer, in the IFAT, of 1600 and 800, respectively; the other two dogs presented no seroconvertion during the 6-month period. Dogs 1 and 2 were euthanized 180 days after infection and were examined for the detection of N. caninum in tissues (brain, muscle, lymph node, liver, lung, heart and bone marrow) by immunohistochemistry and PCR with negative results in both techniques. Bioassay in gerbils with brain of these dogs was also performed and again the results were negative. In conclusion, dogs infected with sporulated oocysts of N. caninum were not able to shed oocysts in feces. However, a higher dose of infection stimulated the production of antibodies against N. caninum in the dogs.  相似文献   
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