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991.
Ascelin Gordon William T. Langford Matt D. White James A. Todd Lucy Bastin 《Biological conservation》2011,(1):558-566
To reduce global biodiversity loss, there is an urgent need to determine the most efficient allocation of conservation resources. Recently, there has been a growing trend for many governments to supplement public ownership and management of reserves with incentive programs for conservation on private land. At the same time, policies to promote conservation on private land are rarely evaluated in terms of their ecological consequences. This raises important questions, such as the extent to which private land conservation can improve conservation outcomes, and how it should be mixed with more traditional public land conservation. We address these questions, using a general framework for modelling environmental policies and a case study examining the conservation of endangered native grasslands to the west of Melbourne, Australia. Specifically, we examine three policies that involve: (i) spending all resources on creating public conservation areas; (ii) spending all resources on an ongoing incentive program where private landholders are paid to manage vegetation on their property with 5-year contracts; and (iii) splitting resources between these two approaches. The performance of each strategy is quantified with a vegetation condition change model that predicts future changes in grassland quality. Of the policies tested, no one policy was always best and policy performance depended on the objectives of those enacting the policy. This work demonstrates a general method for evaluating environmental policies and highlights the utility of a model which combines ecological and socioeconomic processes. 相似文献
992.
Propylene glycol is a common component on aircraft deicingfluids. Runoff from airports may contain high concentrations ofpropylene glycol, leading to a high biological oxygen demand(BOD) in the runoff. Root zone soils support a diverse microbialcommunity and have been shown to enhance biodegradation of numerous compounds. Root zone soils from several grasses andlegumes were tested for their ability to enhance mineralizationof propylene glycol. Propylene glycol (1000 ppm) was applied toroot zone soils incubated at either 22 or 7 °C underdarkened conditions. Root zone soils from legumes showed thehighest rate of mineralization, however, soils from variousgrasses did not show consistently different mineralization ratesfrom each other. Mineralization rates decreased 2.2 to 4.2-foldat the lower temperature; however, treatment soils stillmineralized propylene glycol faster than autoclaved controls. 相似文献
993.
Davis E Rush BR Herr LG Ewert KM 《Veterinary therapeutics : research in applied veterinary medicine》2006,7(3):232-242
Successful clinical management of bacterial pneumonia in horses depends on the administration of an appropriate antimicrobial agent at an adequate dosage and frequency, given by the correct route of administration for an adequate duration. Empiric antimicrobial therapy should be based on the clinician's experience and current veterinary literature. Based on the frequency of Gram-positive bacterial pathogens isolated from horses with bacterial pneumonia, every effort should be made to provide antimicrobial coverage for this class of pathogens. Gram-negative pathogens may co-exist; therefore, broad spectrum antimicrobial coverage may be necessary. Antimicrobial agents posing potential drug related risks (e.g. nephrotoxicity in dehydrated patients, peracute colitis in racehorses) may not be appropriate for empiric use and enrofloxacin offers an enhanced spectrum of antimicrobial activity with reduced risk of complication. Our findings indicate that in cases of exclusive Gram-positive respiratory disease, solo therapy with enrofloxacin is not indicated. 相似文献
994.
Tom Kasiga Ruguang Chen Todd Sink Rebecca Lochmann 《Journal of the World Aquaculture Society》2014,45(5):508-522
Leaf meals are potential alternatives to soybean meal (SBM) in fish diets in developing countries because they are cheaper. Moringa oleifera (MOR) and Leucaena leucocephala (LEU) reduced nutrient digestibility of diets compared with SBM in an earlier study. However, fish raised outdoors consume natural foods, which might offset the negative effects of leaf‐meal diets. We conducted a feeding trial using mixed‐sex Nile tilapia (5.2 g) to assess performance of fish fed 36% protein diets with different concentrations of MOR and LEU leaf meals in place of SBM. Fish in static pools were fed daily to apparent satiation for 59 d. Individual weight gain (30.4–34.7 g), survival (91.8–97.3%), feed conversion ratio (FCR, 1.6–1.9), proximate composition, plasma lysozyme activity, and intestinal proteolytic enzyme activity were similar among diets. However, fish fed diets containing leaf meals had higher concentrations of n‐3 fatty acids than those fed the SBM control. Despite lower nutrient availability of the leaf‐meal diets compared with the soy diet, MOR or LEU could replace up to 30% of the SBM protein without reducing fish performance. Inclusion of poultry meal in the diets and probable nutrient supplementation from natural foods appeared to compensate for the lower nutritional value of the leaf meals compared with SBM. 相似文献
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The management and dissemination of agricultural experiment station and cooperative extension documents have been a challenge for over 100 years. Digitization of these documents, as well as the standardization and public dissemination that such projects can provide, represent both additional obstacles and possible solutions for addressing these challenges. The authors survey the current landscape of digital collections for agricultural experiment station and cooperative extension documents, after which they present a recent, efficient digitization project at the University of Idaho Library as a possible template for other institutions looking to digitize similar documents. 相似文献
997.
Mullins KB Thomason JM Lunsford KV Pinchuk LM Langston VC Wills RW McLaughlin RM Mackin AJ 《Veterinary anaesthesia and analgesia》2012,39(2):206-217
ObjectiveTo determine effects of anti-inflammatory doses of COX-2 selective NSAIDs carprofen, meloxicam, and deracoxib on platelet function in dogs and urine 11-dehydro-thromboxane B2.Study designRandomized, blocked, crossover design with a 14-day washout period.AnimalsHealthy intact female Walker Hounds aged 1–6 years and weighing 20.5–24.2 kg.MethodsDogs were given NSAIDs for 7 days at recommended doses: carprofen (2.2 mg kg?1, PO, every 12 hours), carprofen (4.4 mg kg?1, PO, every 24 hours), meloxicam (0.2 mg kg?1, PO, on the 1st day then 0.1 mg kg?1, PO, every 24 hours), and deracoxib (2 mg kg?1, PO, every 24 hours). Collagen/epinephrine and collagen/ADP PFA-100 cartridges were used to evaluate platelet function before and during and every other day after administration of each drug. Urine 11-dehydro-thromboxane B2 was also measured before and during administration of each drug.ResultsAll NSAIDs significantly prolonged PFA-100 closure times when measured with collagen/epinephrine cartridges, but not with collagen/ADP cartridges. The average duration from drug cessation until return of closure times (collagen/epinephrine cartridges) to baseline values was 11.6, 10.6, 11 and 10.6 days for carprofen (2.2 mg kg?1 every 12 hours), carprofen (4.4 mg kg?1 every 24 hours), meloxicam and deracoxib, respectively.Conclusions and clinical relevanceOral administration of some COX-2 selective NSAIDs causes detectable alterations in platelet function in dogs. As in humans, PFA-100 collagen/ADP cartridges do not reliably detect COX-mediated platelet dysfunction in dogs. Individual assessment of platelet function is advised when administering these drugs prior to surgery, particularly in the presence of other risk factors for bleeding. 相似文献
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