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1.
An update on the 2005 American College of Veterinary Internal Medicine (ACVIM) Consensus Statement on blood donor infectious disease screening was presented at the 2015 ACVIM Forum in Indianapolis, Indiana, followed by panel and audience discussion. The updated consensus statement is presented below. The consensus statement aims to provide guidance on appropriate blood‐borne pathogen testing for canine and feline blood donors in North America.  相似文献   
2.
Forestry practices associated with the industrial era (since ~1900) have altered the natural disturbance regimes and greatly impacted the world’s forests. We quantified twentieth century logging patterns and regional scale consequences in three sub-boreal forest landscapes of Eastern Canada (117,000, 49,400 and 92,300 ha), comparing forestry maps depicting age and forest cover types for early industrial (1930) and present-day (2000) conditions. Results were similar for the three landscapes, indicating large-scale forest change during the twentieth century. In 1930, previous logging activities had been concentrated in the lowlands and along the main hydrographical network, as compared to a more even distribution over the landscapes in 2000, reflecting a decreasing influence of the environmental constraints on forest harvesting. In 1930, old-aged forests (>100 years) accounted for more than 75% of the unlogged areas of the three landscapes, as compared to less than 15% for the present-day conditions. Logging practices have thus inverted the stand age distribution of the landscapes that are currently dominated by young and regenerating stands. The 1930 forest cover types showed a clear relationship with elevation, with conifers located in the lowlands and mixed and deciduous stands restricted to the upper slopes. Between 1930 and 2000, 58–64% of the conifer areas transformed to mixed and deciduous forests, such that no clear altitudinal relationships remained in 2000. We conclude that twentieth century logging practices have strongly altered the preindustrial vegetation patterns in our study area, to the point that ecosystem-based management strategies should be developed to restore conifer dominance, altitudinal gradients, as well as the irregular structure inspired from old forest stands.  相似文献   
3.
The determination of the arterial blood pressure was done on 12 healthy mixed breed dogs in both the anesthetized and the conscious state, to evaluate two instruments (Doppler flow detector and infrasonde D4000), in their ability to indirectly determine arterial blood pressure. The coefficients of variation were higher with indirect methods when compared with the results obtained by cannulation. These coefficients were lower with the Doppler flow detector. The correlation study showed that both apparatuses were reliable in most situations. The infrasonde D4000 was more accurate than the Doppler in the conscious animals. However the results showed a lack of precision in hypertensive conscious dogs. The diastolic arterial blood pressure was particularly precise in the case of the anesthetized hypotensive dogs. Its sensitivity allowed it to register muscle movement artifacts. The Doppler flow detector showed less variation and was particularly accurate in both anesthetized and conscious hypertensive dogs. Its sensitivity allowed artifact movement sounds to be detected. The Doppler should be used in quiet surroundings or earphones should be worn by the evaluator. Some form of restraint is needed with the use of both instruments. Even if the correlations with the direct arterial blood pressure values were better with the infrasonde D4000, greater variations were found in the individual readings. The Doppler instrument represents in the hands of the investigators a better instrument for routine monitoring of blood pressure in the dog.  相似文献   
4.
Based on previous research, cats were thought to have been resistant to the development of clinical signs following infection with Leptospira spp. This case report presents three confirmed, naturally infected clinical cases of feline leptospirosis. The cases presented were all indoor/outdoor cats that were known to hunt. They were also all presented at different stages of renal insufficiency; however, they did not show any liver involvement. The authors suggest that there may be a longer incubation period in cats than dogs and recommend further research in the form of a large, clinical study.  相似文献   
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6.
There is a distinct possibility that the simultaneous sludge digestion and metal leaching (SSDML) process will encounter oxygen limitation, at least for some duration of the process. This is because of the high oxygen requirement, for sulfur oxidation as well as for sludge solids degradation, combined with the low solubility of oxygen. This can alter the system kinetics and downgrade the process performance. The present work focuses on the effect of dissolved oxygen concentration and oxygen transfer rates on the process of sludge acidification. SSDML experiments were carried out in 20 L capacity laboratory reactors as well as a 4000 L capacity pilot plant. It was found that the duration of oxygen limited kinetics is directly proportional to the concentration of biodegradable sludge volatile solids and inversely proportional to the surface area of sulfur and initial concentration of less acidophilic bacteria in the sludge. During this period, the specific growth rates and sulfate production rates of the sulfur oxidizing bacteria are reduced to a fraction of their actual values due to the limitation in oxygen. Based on this information, empirical relations were developed and these were used to simulate oxygen limited SSDML process sequences. The oxygen uptake rate (OUR) and the volumetric oxygen transfer coefficient (kLa) values were calculated for 12 runs carried out in the pilot plant. Increase in kLa obtained by increasing the aeration rates were marginal at higher aeration rates. Also, very high OUR values observed in the complete absence of sulfur oxidizing bacterial activity indicate aerobic digestion to be the predominant oxygen consuming step.  相似文献   
7.
Sediment and water chemistry data were collected from ten lakes within a 110 km radius of Noril'sk in Siberia, the largest smelting complex in the world. Metals showing the most pronounced increase in enrichment near the smelters were Cu, Ni, Co, Ba and Zn. Cu and Ni appear to be as or more enriched in lake sediments around Noril'sk compared with levels previously reported for other locations. Although SO4 concentrations were highly elevated in the areas closest to the smelting complex, lake water pH remained elevated due to high concentrations of base cations in the waters. Sediment mercury enrichment was high in sediments near the smelting complex, but not more so than in other parts of the Arctic, suggesting that Hg either is not a major smelting product at Noril'sk, or that Hg is transported greater distances than other metals due to its longer atmospheric residence time.  相似文献   
8.
Water, Air, & Soil Pollution - Nineteen soil samples (SE Spain) with very different chemical physical properties and developed over different parent materials were contaminated by adding...  相似文献   
9.
This study was conducted to determine the optimal conditions for PAH degradation from highly contaminated attrition sludge (PAC) using a Fenton process or successive permanganate (KMnO4) oxidation and Fenton processes. The following parameters were studied to optimize the Fenton oxidation process: the amounts of reactants based on the stoichiometric oxidant demand (SOD), the reactant addition protocol and number of doses, and the solid/liquid ratio (S/L). The results showed that the following conditions were optimum: TS?=?30%, 7.5 times SOD, H2O2/Fe2+ ratio?=?10, and added five times during 60 min, which allowed the degradation of 43% of total 27 PAHs from the PAC. Successive Fenton and KMnO4 oxidation processes were also tested. PAH degradation using a sequential Fenton process followed by KMnO4 oxidation (or KMnO4 followed by Fenton) was higher than for the use of Fenton or KMnO4 treatment alone. Up to 71% of the total 27 PAHs were degraded when using a combination of both processes. It appeared that the sequential treatment is a viable method for the significant degradation of 27 PAHs from PAC (t value?>?2.77).  相似文献   
10.
Cocamidopropyl hydroxysultaine (CAS) has been used in a pilot plant study as a biodegradable surfactant for the extraction of polycyclic aromatic hydrocarbons (PAHs) and lead (Pb) from contaminated soils. The soil treatment has been done in flotation cells with a concentration of 0.20 g CAS L−1 in saline conditions (3 M NaCl) and using a pulp density of 20% (w/w). The process integrates the recirculation of the liquid phases separated from the soil by centrifugation or filtration. Thus, it was necessary to understand CAS-PAHs micellar behavior and to follow the behavior and the fate of the surfactant in the process. 1-8-anilino-naphthalene sulfonate (ANS) is used as a fluorophor compound in the ANS enhanced fluorescence technique. A three-dimensional model detailing the change in the micellar behavior at high NaCl concentration and at different pH has been established. Fluorescence results of centrifuged soil matrix containing CAS have been compared to the results from synthetic solutions assays. A method allowing an accurate titration of the CAS has been developed by using the exact same matrix of the soil as the tested samples for the preparation of the calibration curves. The study of the surfactant concentration in the process has been performed and allows the adjustment of the CAS concentration in the recirculated water.  相似文献   
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