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51.
《African Journal of Marine Science》2013,35(1):59-65
In order to estimate the absorption rate of carbon by the palinurid lobster Jasus lalandii, the net quantity of ingested carbon and gross carbon content of faeces must be known. Experimental animals were selected for consistent feeding and subsequently starved for 72 h. Ingested carbon was established by determining the carbon content of the prey mussel Choromytilus meridionalis under controlled aquarium conditions through five eating/defaecating cycles. The losses of particulate and dissolved organic carbon due to messy feeding were measured and amounted to 20,1 per cent of the food presented. Of the net carbon ingested, 20,5 per cent was voided as faeces, thereby giving a mean absorption efficiency of 79,5 per cent (n = 15, SD = 4,6%). J. lalandii, as a top carnivore in the inshore Benguela ecosystem, is therefore highly efficient in the utilization of ingested carbon. In animals of commercial size (≥ 89 mm carapace length), small variations in absorption efficiencies exhibited were neither dependent on body mass nor ingested mass, but may rather be attributed to scatter inherent in all biological systems. 相似文献
52.
刺参(Apostichopus japonicus)腐皮综合症发生相关蛋白的分离与鉴定 总被引:1,自引:0,他引:1
采用比较蛋白质组学的方法,对2011年10月20日取自辽宁省普兰店室内养殖厂腐皮综合症刺参和健康个体肠组织中差异表达蛋白进行了研究。结果表明,在优化的电泳条件(80μg脱盐蛋白、pH4—7[NL,13cm]的IPG预制胶条)下,共检测到约700个蛋白质点;表达量差异两倍以上的蛋白点51个,最大表达差异比率为4.32;对其中重复性一致的30个差异点进行质谱鉴定,成功鉴定了23个差异蛋白,包括铁蛋白,过氧化氢酶,泛素相关修饰子3,细胞色素氧化酶和肌动蛋白等;进一步扫描实验室完成的刺参转录组数据,筛选了过氧化氢酶和泛素相关修饰子3的EST序列。本研究是蛋白层面上刺参腐皮综合症发生机制的有效尝试,研究结果为进一步认识该疾病的发生机制提供了参考。 相似文献
53.
The intestinal bacteria of vertebrates form a close relationship with their host.External and internal conditions of the host,including its habitat,affect the intestinal bacterial community.Similarly,the intestinal bacterial community can,in turn,influence the host,particularly with respect to disease resistance.We compared the intestinal bacterial communities of grass carp that were collected from farm-ponds or a lake.We conducted denaturing gradient gel electrophoresis of amplified 16S rRNA genes,from which 66 different operational taxonomic units were identified.Using both the unweighted pair-group method with arithmetic means clustering and principal component analysis ordination,we found that the intestinal bacterial communities from the two groups of pond fish were clustered together and inset into the clusters of wild fish,except for DF-7,and there was no significant correlation between genetic diversity of grass carp and their intestinal bacterial communities(Mantel one-tailed test,R=0.157,P=0.175).Cetobacterium appeared more frequently in the intestine of grass carp collected from pond.A more thorough understanding of the role played by intestinal microbiota on fish health would be of considerable benefit to the aquaculture industry. 相似文献
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Spatial (10 different locations) and temporal (2 years) changes in characteristics of the Marmara Sea Sediments were monitored to determine interactions between the chemical and microbial diversity. The sediments were rich in terms of hydrocarbon, nitrate, Ni and microbial cell content. Denitrifying, sulfate reducing, fermentative and methanogenic organisms were co-abundant in 15 cm below the sea floor. The local variations in the sediments’ characteristics were more distinctive than the temporal ones. The sulfate and nitrate contents were the main drivers of the changes in the microbial community compositions. N and P were limited for microbial growth in the sediments, and their levels determined the total cell abundance and activity. Seasonal shifts in temperatures of the shallow sediments were also reflected in the active cell abundances. It was concluded that the Marmara Sea is a promising ecosystem for the further investigation of the ecologically important microbial processes. 相似文献
58.
Sándor Szalai László Szarka 《Journal of Applied Geophysics》2011,75(1):1-8
Recent two-dimensional multielectrode measurements are restricted to only a few geoelectric arrays. Realizing that specific features of nearly 90 other arrays are totally ignored, all original intentions as published about the development of new geoelectric arrays were reviewed. Apart from arrays, either already applied in two-dimensional geoelectric arrays or impossible to be applied in such systems, 61 forgotten once-developed arrays were found. These provide altogether 102 various solutions, which would be able to increase the efficiency of two-dimensional multielectrode measurements in some respect. 46 array solutions are able to enhance the depth of investigation; 9/11 array solutions give better vertical/horizontal resolution; 17 array solutions provide better planview images; 8 array solutions are worth applying in areas with limited access; 11 array solutions may reduce the effect of near-surface inhomogeneities. By reviving these forgotten arrays, it will be possible to develop versatile multielectrode systems, which are more adaptive to the diverse field needs. 相似文献
59.
应用孤岛油田现场聚合物和美国进口复合有机铬交联剂TIORCOWC684进行了一系列的室内评价实验。实验结果表明,宝莫聚合物均具有较好的初始黏度、且形成的弱冻胶体系强度高;弱冻胶主段塞选取聚合物浓度2500--3000mg/L,交联剂浓度300--600mg/L,成胶强度较高,且胶体不易脱水;弱冻胶封口段塞聚合物浓度为4000mg/L,交联剂浓度300--900mg/L,胶体强度较大、韧性好,满足封口的要求;同时评价了封口段塞的耐盐性能,结果表明该体系随盐类矿化度的增加体系强度有增加趋势。 相似文献
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