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Different values have resulted in conflicts between anglers and conservation lobbies in the management of trout in South Africa. Key to the conflict is the demarcation of boundaries to areas in which brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss currently occur, or are likely to establish following stocking for angling. To provide a longer-term perspective on these areas, we developed models to link salmonid biological thermal thresholds to elevation. These, when applied spatially using a digital elevation model with a probability of occurrence model, provided the basis for estimating potentially available thermal habitat for these two cold water species. Here, we acknowledge that other variables (stocking history; river connectivity) also play a role in understanding trout distributions. Using a simple scenario of an increase in mean daily water temperatures of 2 °C, we demonstrated that both brown and rainbow trout are likely to exhibit considerable range reductions in the future. Because it is possible that these range restrictions will result in an increasing desire to introduce trout into areas above their current distribution limits for the maintenance of angling opportunities, conservation managers should prioritise these areas, with management interventions seeking to understand what will help to limit introductions. 相似文献
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Rimikhanov N. I. Epova E. Yu. Belyakova A. V. Lebedeva A. A. Mutnykh E. S. Biryukova Yu. K. Zylkova M. V. Shibaeva A. V. Trubnikova E. V. Karataeva D. A. Akbaev R. M. Tyno Y. Y. Laypanov B. K. 《Russian Journal of Genetics》2019,55(8):933-938
Russian Journal of Genetics - Owing to the changes in the general ecological situation in Russia, livestock losses from ovine anaplasmosis have rapidly increased in recent years. The development of... 相似文献
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水淹状况是湿地植被动态的重要影响因素。该研究基于谷歌地球引擎(GEE)平台, 利用2000-03-01至2020-02-29所有覆盖研究区域的MODIS遥感影像数据, 分析20年间水淹频率(IF)、增强型植被指数(EVI)的时空变化以及湿地植被对IF变化的响应, 得出以下结论: (1) 20年来鄱阳湖水文节律发生了明显改变, 高IF (IF > 75%)水域面积呈现下降趋势, 从2000年1 435.3 km2下降至2019年的510.25 km2, 降幅为64.45%; (2)区域平均EVI呈显著上升趋势, 植被扩张主要集中在中部IF下降区域; (3)分析不同总水淹频率区域中平均EVI年际变化, 发现EVI与水淹状况的变化趋势相似, 2009年之后鄱阳湖水域面积萎缩趋势缓解, EVI增长速度出现下降; (4)鄱阳湖湿地植被主要沿水域面积萎缩方向扩张, 基于像元统计20年间IF与EVI的变化趋势, 发现它们在空间分布上高度吻合, 这种空间异质性进一步证实水淹状况起到调节植被动态变化的作用。 相似文献
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Abdurashitov MA Belichenko OA Lebedeva NA Degtyarev SK 《Biochemistry. Biokhimii?a》1999,64(4):481-482
PsiI, a novel restriction endonuclease produced by the bacterial strain Pseudomonas sp. SE-G49, has been isolated and characterized. The enzyme cleaves DNA in the middle of its palindromic recognition sequence 5'-TTA downward arrow TAA-3'. Thus, PsiI belongs to a rare group of type II restriction endonucleases whose recognition sites consist of AT base pairs only. 相似文献
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Nudnov NV Kosheleva NV Gamova EV Chaplygina LP Lebedeva MIu Amelichkina MA Khavkin VA 《Vestnik rentgenologii i radiologii》1999,(6):35-38
MRI findings of 13 patients with soft tissue tumors (STT) are presented. There are were abnormalities, such as primary STTs of the hip in 5 patients, the back in 1, and the neck in 1, STT relapses of the hip in 2 and those of the back in 1. Two patients had chronic hip STT hematomas and 1 had hip STT metastatic melanoma. The diagnosis was verified in 11 cases (in 10 cases at surgery and 1 at needle biopsy). MRI makes it possible to define the accurate sizes of the tumor, its structure and relationship to its adjacent tissues, which is important in choosing at treatment policy, the type and scope of a surgical interventions. 相似文献
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Kosse LV Nekliaeva VN Lebedeva SA Zarenkov MI 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1999,(5):81-85
The preparation of Y. pestis capsular antigen F1, isolated from Y. pestis Fra-positive strain by Baker's method, has been shown to have a composition and contain three components: protein, glycoprotein and a lipid-containing component. Each of them equally reacts with antibodies to F1 and diagnostic preparations based on these antibodies. The synthesis of protein and glycoprotein is temperature-dependent and controlled by pYT (Caf). The synthesis of glycoprotein is constitutive and determined by chromosomal genes. Protein and glycoprotein have almost identical mol. wt., 18 and 17 kD respectively, but their localization is different: protein is secreted on the surface of bacterial cells and into the environment, while glycoprotein can be found inside the cells and is similar to intracellular glycoprotein of different enterobacteria, described in our earlier works and exhibiting F1 specificity. Different biological role of these F1-specific components is suggested. 相似文献
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Pavlova LI Gorbunov MA Vorob'eva MS Karavanov AS Grachev VP Ladyshenskaia IP Rasshchepkina MN Mel'nikova LN Lebedeva TM Mel'nikov NA Gusmanova AG Deviatkov MIu Rozanova EV Mukachev MA 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1999,(6):50-53
The word deals with the results obtained in the study of the reactogenicity and immunological activity of concentrated and inactivated tissue-culture tick-borne encephalitis vaccine, manufactured by the Chumakov Institute of Poliomyelitis and Viral Encephalitides, in the immunization of children and adolescents. The vaccine proved to be moderately reactogenic and exhibited pronounced immunological activity. In 91.5% of the immunized children the fourfold increase of the antibody level was observed. On the basis of the data obtained in this study the tick-borne encephalitis vaccine was recommended for use in medical practice for the prophylaxis of tick-borne encephalitis among children and adolescents. 相似文献
30.
Mel'nov SB Lebedeva TB 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2004,44(6):627-631
In the present investigation the analysis of the cytogenetic status and some blood characteristics of the adolescents from the contaminated area of Vulka-2 in Belarus has been done. The obtained data testifed that patients living in the condition of chronic radiation influence had essentially increased general frequency of all types of chromosome aberrations. First of all the elevated level of radiation markers is marked (0.54 +/- 0.11 and 0.11 +/- 0.05% in control. group, p < 0.05), the growth of double fragments (1.27 +/- 0.17 and 0.40 +/- 0.09% in control group, p < 0.05). The Spearmen correlation alalysis has revealed statistically significant increase of apoptosis level on the background of increased level of micronuclei (R = 0.832, p < 0.01). Thus our data testify that the degree of the biological homeostasis violation is intimately connected with the level of genome destabilization. 相似文献