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51.
The moderately halophilic strain Salinivibrio sp. EG9S8QL was isolated among 11 halophilic strains from saline mud (Emisal Salt Company, Lake Qarun, Fayoum, Egypt). The lipopolysaccharide was extracted from dried cells of Salinivibrio sp. EG9S8QL by the phenol–water procedure. The OPS was obtained by mild acid hydrolysis of the lipopolysaccharide and was studied by sugar analysis along with 1H and 13C NMR spectroscopy, including 1H,1H COSY, TOCSY, ROESY, 1H,13C HSQC, and HMBC experiments. The OPS was found to be composed of linear tetrasaccharide repeating units of the following structure: →2)-β-Manp4Lac-(1→3)-α-ManpNAc-(1→3)-β-Rhap-(1→4)-α-GlcpNAc-(1→, where Manp4Lac is 4-O-[1-carboxyethyl]mannose.  相似文献   
52.
A blinded randomized study was conducted on 24 cats to confirm the presence of bacterial and/or fungal secondary infections associated with otoacariasis and to verify the efficacy of Oridermyl, an acaricidal/antibiotic/antifungal/anti-inflammatory ointment, for treatment of the primary infestation and secondary infections. Sixteen cats were treated once daily for 10 d; 4 cats were not treated and 4 were treated with a placebo ointment. On Days 0 and 10, ears were swabbed for counts of bacteria and yeasts, for bacterial culture and sensitivity, and examined for determination of the degree of clinical otitis. Auricular secretions were removed for mite counts on Day 10, except for 8 treated cats that were done on Day 30. There was a high number of bacteria and yeasts in most cats and Oridermyl treatment significantly decreased those numbers. Staphylococci were the most frequently isolated bacteria. No live ear mites were found in cats treated with Oridermyl or the placebo ointment.  相似文献   
53.
在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。  相似文献   
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55.
Cerium binding activity of three different water soluble pectin compounds of different origin was studied in a batch sorption system. The Langmuir, Freundlich and BET sorption models were adopted to describe the binding reactions between metal ions and pectin molecules. The Langmuir model provided the best fit. Within the pH range from 4.0 to 6.0, the largest amount of the cerium ions was bound by pectin isolated from the seagrass Phylospadix iwatensis in comparison to pectin extracted from the seagrass Zostera marina and pectin obtained from citrus peel (commercial grade). The Langmuir constants were also highest for the pectin samples isolated from the seagrass P. iwatensis. The results obtained from this study suggest that pectin is a prospective source for the development of radioisotope-removing pharmaceuticals.  相似文献   
56.
Understanding the spatial pattern of fire is essential for Mediterranean vegetation management. Fire-risk maps are typically constructed at coarse resolutions using vegetation maps with limited capacity for prescribing prevention activities. This paper describes and evaluates a novel approach for fire risk assessment that may produce a decision support system for actual fire management at fine scales. FARSITE, a two-dimensional fire growth and behavior model was activated, using ArcView VBA code, to generate Monte Carlo simulations of fire spread. The study area was 300 km2 of Mt. Carmel, Israel. FARSITE fuel models were adjusted for Mediterranean conditions. The simulation session consisted of 500 runs. For each simulation run, a calendar date, fire length, ignition location, climatic data and other parameters were selected randomly from known distributions of these parameters. Distance from road served as a proxy for the probability of ignition. The resulting 500 maps of fire distribution (the entire area burnt in a specific fire) were overlaid to produce a map of ‘hotspots’ and ‘cold spots’ of fire frequency. The results revealed a clear pattern of fires, with high frequency areas concentrated in the northwestern part. The spatial pattern of the fire frequency map bears partial resemblance to the fuel map, but seems to be affected by several other factors as well, including the location of urban areas, microclimate, topography and the distribution of ignition locations (which is affected by road pattern). These results demonstrate the complexities of fire behavior, showing a very clear pattern of risk level even at fine scales, where neighboring areas have different risk levels due to combinations of vegetation cover, topography, microclimate and other factors.  相似文献   
57.
由于种群数量的急剧下降和分布区缩小,黄颊麦鸡(Vanellus gregarius)近期被IUCN提升为极危物种.该物种至今在中国唯一一个发表的记录是1998年见到的迷鸟.我们查阅了一个德国鸟类考察队1876年的报告和历史文献.该报告认为黄颊麦鸡在19世纪下半叶在中国西部的新疆为繁殖鸟.根据当地专家推测,该物种已在新疆绝灭.本文建议开展调查以阐明其现状.  相似文献   
58.
Several nonthyroidal illnesses in euthyroid dogs can affect the results of thyroid function testing, making interpretation of the results more difficult with an increased risk of overdiagnosing hypothyroidism. The purpose of this study was to evaluate the effect of chronic, moderate to severe, osteoarthritis on canine thyroid function. Ninety-six, healthy, client-owned dogs, 65 of which were suffering from moderate to severe osteoarthritis and 31 euthyroid dogs without any physical evidence of osteoarthritis, were used in this study. Blood samples were collected to evaluate serum basal total thyroxine (TT4), free thyroxine (FT4), and thyrotropin (TSHc) concentrations. Basal serum TT4 concentration was not affected by osteoarthritis in dogs. Mild, but statistically significant, differences were noticed in FT4 and TSHc concentrations among the 2 groups. However, this had limited clinical relevance, since virtually all values were within their reference range, and no dogs would have been misdiagnosed as hypothyroid. Therefore, based on the results of our study, osteoarthritis does not need to be considered a factor influencing thyroid function evaluation in dogs.  相似文献   
59.
The well-ordered aluminum oxide film formed by oxidation of the NiAl(110) surface is the most intensely studied metal surface oxide, but its structure was previously unknown. We determined the structure by extensive ab initio modeling and scanning tunneling microscopy experiments. Because the topmost aluminum atoms are pyramidally and tetrahedrally coordinated, the surface is different from all Al2O3 bulk phases. The film is a wide-gap insulator, although the overall stoichiometry of the film is not Al2O3 but Al10O13. We propose that the same building blocks can be found on the surfaces of bulk oxides, such as the reduced corundum (0001) surface.  相似文献   
60.
The use of the “integrative approach” for classification of organisms since its formal establishment in 2005 has become a recurrent theme of zoosystematics. A bibliometric survey of the publications on integrative taxonomy of animals, which is aimed at exploring the most popular areas of research and characterizing the practical systematists’ attitudes to this new approach, is presented. An analysis of 582 papers, which appeared between 2005 and 2017 in journals indexed by Scopus and the Web of Science Core Collection, has illustrated the gradual growth of the popularity of integrative taxonomy as well as some biases in the representation of higher taxa in “integrated” studies. It has been shown that the “integrative” papers have more chance of appearing in a top‐ranking journal and gain relatively more citations as compared with non‐integrative papers. The obtained results are discussed in the context of the “taxonomic impediment” problem thought to be a consequence of the institutional crisis of traditional taxonomy, which has been vividly debated over the past decades.  相似文献   
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