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This paper considers farmers’ willingness to pay (WTP) to conserve an endangered Irish farmland bird, the corncrake (Crex crex). An Irish National Farm Survey is used to produce individual farm-level WTP estimates for the year 2006. These figures are then aggregated to obtain a total value figure for the farming community of corncrake conservation in Ireland. We focus on the willingness to pay of farmers rather than the WTP of the general Irish population, as farmers will ultimately be the ones that will have to take responsibility if targets set out in the All Ireland Action Plan for corncrake conservation are to be achieved. Quantifying willingness to pay on the part of farmers can help inform the design of agri-environment schemes aimed at improving conservation of many bird species on farmland. Results indicate that the non-market benefit of corncrake conservation in Ireland may significantly outweigh the costs of existing conservation schemes.  相似文献   
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A metabolically protected analog of substance P, [pGlu5-MePhe8-MeGly9]SP(5-11) (DiMe-C7), was approximately equipotent with substance P in causing increased locomotor activity after microinfusion into the ventral tegmental area of rat brain, but the effects of DiMe-C7 on behavior were considerably prolonged. There was little metabolic degradation of tritiated DiMe-C7 for up to 1 hour after infusion, whereas tritiated substance P was completely degraded within 10 minutes.  相似文献   
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An adult female, radiated tortoise (Geochelone radiata) presented with a grossly swollen left forelimb that restricted mobility and prevented limb withdrawal. Clinical pathology revealed leukopenia (1.9 x 10(9)/L) and hyperproteinemia (69 g/L) that on protein electrophoresis was attributed to increased acute-phase proteins in the alpha fraction (26.4 g/L). Biopsy revealed a poorly differentiated soft tissue sarcoma. Surgical amputation at the proximal humerus was curative. To encourage postoperative mobility, a novel methylmethacrylate prosthesis, molded from a lubricated transected tennis ball, was adhered to the plastron using three cortical bone screws. This is the first recorded case of a sarcoma in the genus Geochelone.  相似文献   
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On the basis of synchronization of three carbon-14 (14C)-dated lacustrine sequences from Sweden with tree ring and ice core records, the absolute age of the Younger Dryas-Preboreal climatic shift was determined to be 11,450 to 11,390 +/- 80 years before the present. A 150-year-long cooling in the early Preboreal, associated with rising Delta14C values, is evident in all records and indicates an ocean ventilation change. This cooling is similar to earlier deglacial coolings, and box-model calculations suggest that they all may have been the result of increased freshwater forcing that inhibited the strength of the North Atlantic heat conveyor, although the Younger Dryas may have begun as an anomalous meltwater event.  相似文献   
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A 32.5-year-old female hybrid orangutan (Pongo pygmaeus) developed hind-limb stiffness that progressed to tetraparesis over 2 wk. Repeated diagnostic evaluations, including serial magnetic resonance imaging of the central nervous system, revealed nonspecific lesions involving both the deep white and gray matter with an intact blood-brain barrier. Multiple empirical treatments failed to produce improvement and the animal was humanely euthanized. Histology of a granuloma in the ileum contained a nematode parasite, most consistent with Baylisascaris procyonis. Additionally, neuropil vacuolization, rarefaction, astrocytic scarring, and an eosinophilic granuloma and lymphoeosinophilic perivascular cuffing in the brain were suggestive of nematode migration. These findings confirm the presence of visceral larval migrans and support the presence of neural larval migrans. This case report of Baylisascaris procyonis confirms the presentation for the first time in an ape and documents the difficulty in antemortem diagnosis of neural larval migrans.  相似文献   
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The effects of biochar properties on crop growth are little understood. Therefore, biochar was produced from eight feedstocks and pyrolyzed at four temperatures (300°C, 400°C, 500°C, 600°C) using slow pyrolysis. Corn was grown for 46 days in a greenhouse pot trial on a temperate and moderately fertile Alfisol amended with the biochar at application rates of 0.0%, 0.2%, 0.5%, 2.0%, and 7.0% (w/w) (equivalent to 0.0, 2.6, 6.5, 26, and 91 t biochar ha−1) and full recommended fertilization. Animal manure biochars increased biomass by up to 43% and corn stover biochar by up to 30%, while food waste biochar decreased biomass by up to 92% in relation to similarly fertilized controls (all P < 0.05). Increasing the pyrolysis temperature from 300°C to 600°C decreased the negative effect of food waste as well as paper sludge biochars. On average, plant growth was the highest with additions of biochar produced at a pyrolysis temperature of 500°C (P < 0.05), but feedstock type caused eight times more variation in growth than pyrolysis temperature. Biochar application rates above 2.0% (w/w) (equivalent to 26 t ha−1) did generally not improve corn growth and rather decreased growth when biochars produced from dairy manure, paper sludge, or food waste were applied. Crop N uptake was 15% greater than the fully fertilized control (P < 0.05, average at 300°C) at a biochar application rate of 0.2% but decreased with greater application to 16% below the N uptake of the control at an application rate of 7%. Volatile matter or ash content in biochar did not correlate with crop growth or N uptake (P > 0.05), and greater pH had only a weak positive relationship with growth at intermediate application rates. Greater nutrient contents (N, P, K, Mg) improved growth at low application rates of 0.2% and 0.5%, but Na reduced growth at high application rates of 2.0% and 7.0% in the studied fertile Alfisol.  相似文献   
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