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During the past two decades with farmer participation in irrigation management moving to center stage, the traditional view of having a centralized control over the water resources for better management has changed. Nevertheless, success of irrigation management transfer depend on a whole set of institutional arrangements or the rules-in-use and the willingness of the users to comply and enforce and/or change the rules in the light of changing circumstances. There are many institutional analyses of water sector, much of them touch on law, policy and administration, and characteristics of the users. The present paper is based on the study carried out to examine the institutional arrangements in one of the water users association that was first in the Maharashtra state. It focuses on the institutional arrangements governing water use and distribution and attempts to elicit the perceptions of the members regarding the rules-in-use. The findings reveal that the WUA has been successful in devising and enforcing the rules for water distribution, fee collection and conflict resolution for over a decade. However, current socio-economic developments such as political heterogeneity have required explicit conflict resolution mechanisms. These issues have now become issues demanding immediate attention and may be use of existing courts or legal institutions to help the WUA sustain in future. 相似文献
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Jennifer Harris-Hellal Tatiana Vallaeys Evelyne Garnier-Zarli Noureddine Bousserrhine 《Applied soil ecology》2009,41(1):59-68
In gold mining regions, the risk of soil pollution by mercury is a major environmental hazard, especially in tropical areas where soil microflora plays a major part in soil functioning, major bio-geochemical cycles and carbon turn-over. The impact of mercury pollution on soil microflora should thus be carefully assessed in such environments while taking into consideration the specificities of tropical soils. The aim of this study was to compare the effects of mercury (0, 1 and 20 μg of inorganic mercury per gram of soil) on the functional diversity and genetic structure of microbial communities in a tropical soil. We investigated the effects of mercury on tropical soil microflora using soil microcosms spiked with mercury and incubated at 28 °C for 1 month. Microcosm flora, its biomass and its activity, as well as its functional and genetic structure, were followed by cultural methods, measures of respiration, ECOLOG plates, and DGGE (denaturing gel gradient electrophoresis), respectively. Fate of total and bioavailable mercury was estimated by CVAFS (cold vapor atomic fluorescence spectrometry). Results obtained for the microcosms enriched with only 1 μg g?1 mercury were indistinguishable from controls. Conversely, in the presence of high mercury contents (20 μg g(1), an immediate effect was measured on soil respiration, functional diversity (ECOLOG plates) and genetic structure (DGGE), although no significant effect was observed on plate counts or microbial biomass. In addition, whereas microbial activities (respiration and functional diversity) rapidly regained control values, a lasting effect of the high mercury concentration was observed on the genetic structure of the soil microbial community. These modifications took place during the first week of incubation when total mercury concentration was declining and bioavailable mercury was at its highest.This multiple approach study is one of the first attempts at investigating the effects of mercury on soil microbial communities in tropical soils. Our results demonstrate that in the tropical soil under study, mercury affects the soil microbial communities in a different manner than was previously reported in temperate soils. Furthermore, mercury toxicity on soil microbes may be modulated by typical tropical soil characteristics. 相似文献
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Brian J. Trumpatori Jennifer E. Carter Jon Hash Gigi S. Davidson Kyle G. Mathews Simon C. Roe B. Duncan X. Lascelles 《Veterinary surgery : VS》2010,39(7):785-796
Objective: To evaluate a technique for midhumeral peripheral nerve blockade in the dog. Study Design: Cadaveric technique development; in vivo placebo‐controlled, prospective crossover study. Animals: Canine cadavers (n=38) and 8 clinically healthy, adult hound dogs. Methods: A technique for peripheral block of the radial, ulnar, musculocutaneous, and median nerves (RUMM block) was evaluated using cadaver limbs. Eight purpose‐bred, research dogs were anesthetized; a RUMM block was performed on each thoracic limb. One limb from each dog randomly received 0.5% bupivacaine and the opposite limb was assigned to receive sterile saline solution as a control. After recovery from anesthesia, skin sensation at selected dermatomes was evaluated for 24 hours using a mechanical stimulus. Weight‐bearing, conscious proprioception, and withdrawal reflex were also evaluated. One month after initial testing, each dog was reanesthetized and each limb received the opposite treatment. Results: Sensory thresholds were significantly increased over baseline measurements when compared with control limbs for all nerves. Complete sensory block was achieved in radial (15/16), ulnar (3/16), musculocutaneous (8/16), and median (11/16) nerves, using a mechanical stimulus of analgesia. Complete simultaneous block of all nerves was only obtained in 1 of 16 limbs. Conclusion: RUMM block resulted in desensitization of the skin in the associated dermatomes for 4–10 hours. Complete sensory block of the dermatomes supplied by the radial nerve was most consistent. Clinical Relevance: RUMM block may be an effective technique to provide adjunctive analgesia for dogs undergoing surgery of the distal aspect of the thoracic limb. 相似文献
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Eunice J. Allan Janakie P. Eeswara Shaun Johnson A. Jennifer Mordue E. David Morgan Trevor Stuchbury 《Pest management science》1994,42(3):147-152
Callus produced from leaves of a Ghanaian strain of the neem tree, Azadirachta indica A. Juss has been shown to produce the natural insecticide azadirachtin when grown in a defined medium. The azadirachtin was isolated by standard procedures of solvent partition and column chromatography monitored by supercritical fluid chromatography. Biological activity was monitored with antifeedant tests using the desert locust (Schistocerca gregaria Forsk.). The azadirachtin was identified by chromatography on three independent chromatographic systems (SFC, HPLC & TLC) and two thin-layer colour tests. It has 100% antifeedant activity at < 0.04mg litre?1. The yield of azadirachtin was 0.0007% based on dry weight of callus. 相似文献
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Allyson C. Berent DVM Jeffrey Todd DVM Jennifer Sergeeff DVM DACVIM Lisa L. Powell DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2005,15(2):128-135
Objective: To describe diagnostics, therapy, and sequelae of acute carbon monoxide (CO) toxicity because of a motor vehicle generator in 4 dogs and 2 cats. Series summary: Four dogs and 2 cats presented for recumbency, disorientation, dyspnea, and stiffness after an estimated 6–8 hour exposure to exhaust from a generator. Diagnostics included a serum carboxyhemoglobin levels evaluation, arterial blood gas analysis, pulse oximetry readings, and blood pressure measurements. Initial therapy included oxygen (O2) administration, intravenous bronchodilators, fluids, and a hemoglobin‐based O2 carrying (HBOC) molecule. Following administration of the HBOC, 4 of the 6 animals showed dramatic clinical improvement. Two weeks after hospital discharge, the owner reported potential hearing deficits in all animals. Brain auditory evoked response (BAER) tests were conducted in all surviving animals and some degree of hearing impairment was documented in all cases, with complete clinical resolution noted 6 weeks later. Unique information provided: This report describes the therapeutic use of an HBOC in acute isolated CO toxicity (i.e. without the complications of smoke inhalation). In addition, delayed nervous system dysfunction was documented in all surviving animals. 相似文献
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OBJECTIVE: To determine the hemodynamic effects of nitrous oxide in isoflurane-anesthetized cats. ANIMALS: 12 healthy adult domestic shorthair cats. PROCEDURE: Cats were anesthetized by administration of isoflurane in oxygen. After instruments were inserted, end-tidal isoflurane concentration was set at 1.25 times the individual minimum alveolar concentration, and nitrous oxide was administered in a Latin-square design at 0, 30, 50, and 70%. Each concentration was administered for 25 minutes before measurements were obtained to allow for stabilization. Heart rate; systemic and pulmonary arterial pressures; central venous pressure; pulmonary artery occlusion pressure; cardiac output; body temperature; arterial and mixed-venous pH, PCO2, PO2, and hemoglobin concentrations; PCV; and total protein and lactate concentrations were measured before and during noxious stimulation for each nitrous oxide concentration. Arterial and mixed-venous bicarbonate concentrations and oxygen saturation, cardiac index, stroke index, rate-pressure product, systemic and pulmonary vascular resistance indices, left and right ventricular stroke work indices, arterial and mixed-venous oxygen contents, oxygen delivery, oxygen consumption, oxygen extraction ratio, alveolar-to-arterial oxygen difference, and venous admixture were calculated. RESULTS: Arterial pressure, central venous pressure, pulmonary arterial pressure, rate-pressure product, systemic and pulmonary vascular resistance indices, arterial PCO2, and PCV increased during administration of 70% nitrous oxide. Arterial and mixed-venous pH, mixed-venous PO2, and alveolar-to-arterial oxygen difference decreased during administration of 70% nitrous oxide. Results before and during noxious stimulation were similar. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of 70% nitrous oxide to isoflurane-anesthetized cats resulted in improved arterial pressure, which was related to a vasoconstrictive effect. 相似文献