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71.
胡少波 《中国农村水利水电》1992,(7)
地方小水电网由于网络结构复杂,运行方式变化频繁,对继电保护的正确动作带来了很大的影响。根据地区电网多年运行的情况,对保护的整定计算方法等提出了一些改进措施和建议。 相似文献
72.
World Small Animal Veterinary Association Nutritional Assessment Guidelines Task Force 《Journal of the South African Veterinary Association》2011,82(4):254-263
Careful assessment of nutritional needs of dogs and cats must be taken into consideration in order to maintain optimum health, be part of a treatment regimen for a diseased state, or to maximise the quality of life in all animals. Therefore, the goal of these WSAVA Guidelines is that a nutritional assessment and specific nutritional recommendation be made on every patient on every visit. This will become known as the 5th Vital Assessment (5VA), following the four vital assessments of temperature, pulse, respiration and pain that are already addressed on each patient interaction. Routinely doing a brief screening evaluation of the nutritional status during history taking and the physical examination can be seamlessly performed as part of every patient exam. Nutrition-related risk factors that can be easily identified from the history and physical examination include age (growing or old), suboptimal body condition score (overweight or thin), muscle loss, atypical or homemade diet, medical conditions, or changes in appetite. An extended evaluation would follow, if one or more risk factors is identified on screening. These guidelines provide criteria to evaluate the animal and the diet, as well as key feeding and environmental factors. In addition, recommendations for interpretation, analysis, and action are included so that a plan for optimising the animal's nutritional status can be instituted. Client compliance with nutritional recommendations requires input from the veterinarian, veterinary technicians/nurses, and the hospital staff. A team approach to continuous nutritional education, implementation of appropriate protocols, and focused client communication, utilising these WSAVA Nutritional Guidelines, are key components to reach this 5VA goal. 相似文献
73.
GJ EAMENS PD KIRKLAND MJ TURNER JA GARDNER† MP WHITE‡ CL HORNITZKY 《Australian veterinary journal》1988,65(4):120-123
Toxigenic strains of Pasteurella multocida were readily differentiated from non-toxigenic strains by an agarose overlay method using bovine turbinate cells or bovine lung cells. Cells which were young and densely confluent were best suited to this assay. The incubation period required to distinguish toxigenic strains was dependent on the confluence of the monolayers, which was affected by the seeding rate, cell passage level and growth time prior to overlay. The agarose overlay method correctly identified 11 of 11 reference strains of Pasteurella multocida, and visible cytotoxic changes were present in the monolayers after 48 to 65 h. Outbreaks of the enzootic form of atrophic rhinitis in 2 New South Wales piggeries were associated with the isolation of toxigenic type D strains of P. multocida. 相似文献
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Sinha R. Small M. J. Ryan P. F. Sullivan T. J. Cosby B. J. 《Water, air, and soil pollution》1998,105(3-4):617-642
A reduced-from modelling approach is used to predict soil and lake acidification as part of an integrated assessment of acid deposition effects and control strategies. The reduced-form model is based upon the mechanistic, lumped parameter watershed chemistry model, MAGIC (Model of Acidification of Groundwater in Catchments). Recent improvements to MAGIC are described, and its reduced-form representation in the Tracking and Analysis Framework (TAF), an integrated assessment model for decision and uncertainty analysis, is presented. Reduced-form models are developed for lake acid neutralising capacity (ANC), calcium, pH, and aluminium; and for soil base saturation. The model for lake ANC incorporates long-term depletion of the watershed acid neutralisation fraction, as is predicted to occur with MAGIC. In test calibrations for 33 representative watersheds in the Adirondacks, the resulting reduced-form model provides a close approximation to MAGIC, with average root mean square errors of 0.79 μeq l-1 for ANC, 1.09 μeq l-1 for calcium, 0.16 for pH, 2.52 μeq l-1 for aluminium, and 0.09% for soil base saturation. In addition, improved fish viability models are incorporated in the integrated assessment model, and predictions are demonstrated for a future deposition reduction scenario for the Adirondack region. 相似文献
79.
The structure of the upper atmosphere of mars: In situ accelerometer measurements from mars global surveyor 总被引:1,自引:0,他引:1
GM Keating SW Bougher RW Zurek RH Tolson GJ Cancro SN Noll JS Parker TJ Schellenberg RW Shane BL Wilkerson JR Murphy JL Hollingsworth RM Haberle M Joshi JC Pearl BJ Conrath MD Smith RT Clancy RC Blanchard RG Wilmoth DF Rault TZ Martin DT Lyons PB Esposito MD Johnston al et 《Science (New York, N.Y.)》1998,279(5357):1672-1676
The Mars Global Surveyor (MGS) z-axis accelerometer has obtained over 200 vertical structures of thermospheric density, temperature, and pressure, ranging from 110 to 170 kilometers, compared to only three previous such vertical structures. In November 1997, a regional dust storm in the Southern Hemisphere triggered an unexpectedly large thermospheric response at mid-northern latitudes, increasing the altitude of thermospheric pressure surfaces there by as much as 8 kilometers and indicating a strong global thermospheric response to a regional dust storm. Throughout the MGS mission, thermospheric density bulges have been detected on opposite sides of the planet near 90 degreesE and 90 degreesW, in the vicinity of maximum terrain heights. This wave 2 pattern may be caused by topographically-forced planetary waves propagating up from the lower atmosphere. 相似文献
80.
About 700 sheep died on 52 farms in north-western New South Wales and south-western Queensland over a 3 mo period. Affected animals had a marked asymmetrical swelling of the face, extending from the nostril to just anterior to the eyes. They lost condition rapidly and died within 7 to 10 days. At necropsy there was a unilateral severe necrogranulomatous rhinitis with extension of inflammation into the adjacent subcutaneous tissue, nasal septum and hard palate. Metastatic lesions were present in the draining lymph nodes and in the thorax. Histological changes consisted of a granulomatous reaction with numerous eosinophilic foci of necrosis and a diffuse, heavy, mixed inflammatory cell response. Many vessels had segmental necrosis and thrombosis. Fungal hyphae were numerous, particularly within or associated with necrotic foci. Conidiobolus incongruus was isolated from nasal tissues, parotid and submandibular lymph nodes and pulmonary lesions. 相似文献