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Deep-water corals are slow growing, fragile and vulnerable to the impacts of deep-water fisheries and the development activities of the offshore industries. In Ireland there is now evidence of major damage to deep-water corals linked to a recent expansion of the Irish deep-water fishery. This fishery uses trawls fitted with robust rock hopping gear and employs a high risk fishing technique, which is potentially very destructive to coral habitats. Consequently resource managers have been exploring the potential of marine protected areas (MPA) as a tool for the conservation of these coral ecosystems in the North East Atlantic. MPAs aim to minimise the socio-economic costs associated with closures or other management restrictions while still achieving the desired conservation objectives. However, the decision to use MPAs (and thereby restrict fishing) is often taken in the light of uncertainty over the value of the reserved habitats to the fishing industry. This paper reports on a choice experiment study carried out in Ireland in early 2007 aimed at partly addressing this uncertainty. The study primarily focused on determining the economic value held by the Irish public for the conservation of deep-sea corals using several variants of the concept of MPAs. They have endorsed MPA strategies that banned trawling in an MPA that included all areas where corals are thought to exist with no personal tax imposed, banned trawling in an MPA covering all known corals with a personal tax imposed of €1 p.a. and banned all fishing in an MPA covering all areas where corals are thought to exist with a personal tax imposed of €1 p.a. In terms of the probabilities attached to the individual attributes, the most preferred policy options were to ban trawling, protect all areas where corals are thought to exist, and pay a ring-fenced personal tax of €1 p.a.  相似文献   
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Five parents of common vetch (Vicia sativa L.) having orange/beige cotyledon colour, brown/white testa colour, purple/green seedling colour and purple/white flower colour were crossed as a full diallele set. The inheritance patterns of cotyledon, testa or seed coat colour, flower and seedling colour, were studied by analyzing their F1, F2, BC1 and BC2 generations. The segregation pattern in F2, BC1 and BC2, showed that cotyledon colour was governed by a single gene with incomplete dominance and it is proposed that cotyledon colour is controlled by two allelic genes, which have been designated Ct1 and Ct2. Testa colour was governed by a single gene with the brown allele dominant and the recessive allele white. This gene has been given the symbol H. Two complementary genes governed both flower and seedling colours. These flower and seedling colour genes are pleiotropic and the two genes have been given the symbols S and F.  相似文献   
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A high temperature/low oxygen pulse improves cold storage disinfestation   总被引:4,自引:0,他引:4  
Short periods of elevated temperature under controlled atmospheres (CA) effectively control insect pests. Cold treatment is also an effective non-chemical disinfestation process. If synergistic effects can be found by combining treatments, these may provide opportunities for cost reduction. Tests were performed to evaluate the tolerance of Packham's Triumph pears (Pyrus communis L.) to a range of temperatures (30–40 °C) combined with low oxygen (O2 < 1 kPa). Treatment duration was 16–48 h and was followed by 1 month storage at 0 °C under air. When held at 30 °C, pears withstood up to 30 h of hypoxia. After cold storage, pears ripened slightly faster than controls but were undamaged. A temperature of 35 °C induced slight skin browning, and 40 °C resulted in substantial skin blackening. Some treatments were also tested on survival of lightbrown apple moth (LBAM), Epiphyas postvittana (Walker). All developmental stages were subjected to either 16 h at 30 °C, or 16 h under hypoxia, or 1 month at 0 °C, or a combination of the three treatments. With all treatments combined, all eggs, larvae and adults were killed. Only 4% of the pupae produced adults and combined treatments led to an increase in pupa mortality of 38%. A combined treatment (tolerated by pears) consisting of 30 h at 30 °C under low O2 plus 1 month cold storage under air, killed 100% of LBAM pupae, and 100% of 5th instar larvae of both codling moth, Cydia pomonella (L.), and oriental fruit moth, Grapholita molesta (Busck). Implementation of such treatments would not require substantial investments for fruit industries equipped with CA storage facilities.  相似文献   
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Arid land and riparian plants were irrigated with a liquid wastewater stream (centrate) from biosolids production at a municipal sewage treatment facility. Centrate containing approximately 1000 mg/l ammonia nitrogen was diluted with Tucson city tap water to provide treatments of 2.5, 5, 10, 25, 50, and 100% centrate, along with a dilution water control. Plants grown in 19-l containers in a greenhouse were irrigated daily with 6.7 l of solution over a 7-week period. All species exhibited a fertilizing effect at concentrations up to 5 and 10% centrate, equivalent to approximately 50 and 100 mg/l NH3–N, but then inhibitory above 100 mg/l. No plants survived on the 50 or 100% treatments. If centrate were to be diverted from the wastewater facility to be disposed of on the land, it was estimated that the total nitrogen content of the biosolids produced by the plant would be reduced by 11%. This reduction would have only a small impact on the value of the biosolids for soil amendment applications.  相似文献   
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To obtain structure-function information of a range of carbohydrates, which are available only in very small quantities, an in vitro fermentation method using 7 mg of carbohydrate, 0.7 mL of basal medium, and 1% (w/v) of fecal bacteria was validated against a pH-controlled batch culture with 150 mL of basal medium and 1.5 g of test carbohydrate. This method was used to determine the influence of different glycosidic linkages and monosaccharide compositions of disaccharides on the selectivity of microbial fermentation. A prebiotic index (PI) was calculated for each disaccharide. Generally, disaccharides with linkages of 1-2, 1-4, and 1-6 generated a high PI score, with kojibiose and sophorose showing the greatest values (21.62 and 18.63, respectively). Apart from 6alpha-mannobiose, mannose-containing disaccharides gave a low PI due to low numbers of bifidobacteria and lactobacilli and an increase in bacteroides. The structure-function information obtained in this study may lead to a predictive understanding of how specific structures are fermented by the human gut microflora.  相似文献   
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Our experience in developing models to predict the potential impacts of oil spills on colonially breeding marine birds has revealed some major gaps in the information available on these systems. We consider the availability of data for a variety of parameters of seabird biology that are required in modelling efforts, and assign provisional priorities to our information needs. In order to develop means of predicting the impacts of oil spills on seabirds, we suggest that colony- or site-specific information on the timing of reproduction and colony occupancy, chick growth rates and body weights, several metabolic parameters, flight speed, and food load size is of relatively low overall priority. Intermediate priority is assigned to the collection of specific data on the dynamics of oil spills, the age and breeding structure of the populations, reproductive success, foraging activity budgets and flight paths, flight costs, and the response of growing chicks to food deprivation. We suggest that studies of seabird biology should give highest priority to obtaining information on population sizes, the probability of adult death upon encountering a spill, age-specific fecundity and survivorship, the time required in foraging trips, the lag time in the response of birds to an oil spill, foraging rate as a function of resource density, and changes in the availability of resources to the birds as a consequence of oil spills.  相似文献   
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Unfortunate bovine fatalities occurring after ingestion of mold-damaged sweetpotatoes preclude the use of the culled tubers in livestock feed. In cattle, mold-damaged sweetpotatoes induce an acute respiratory distress syndrome resulting in asphyxiation. Because of this potential toxicity and the general abundance of culled sweetpotatoes, the detoxification efficacy of ensiling was explored since it is an easy and economically viable technique often applied to preserve livestock feed. Sweetpotato slices with or without mold damage were stored either frozen (to represent unfermented samples) or fermented for 6 weeks at room temperature. Following fermentation, organic extracts were generated for administration to mice. Thirty hours following administration of the extracts, mice were evaluated for gross and microscopic lesions affecting the lungs, liver, and kidneys. Fermentation of 6 weeks duration was observed to inadequately eliminate the lung, liver, and kidney toxicity caused by mold-damaged sweetpotatoes. In fact, fermentation exacerbated the hepatotoxicity of mold-damaged sweetpotatoes. This is also the first demonstration that sweetpotato regions lacking visible mold damage can induce lung and kidney injury, which, however, is preventable by fermentation.  相似文献   
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