Serengeti III: Human Impacts on Ecosystem Dynamics

During a survey of seals in September and October 2009 at Gough Island, South Atlantic Ocean, we recorded goose barnacles (Lepas australis) attached to the pelage of two of the 12 elephant seals (Mirounga leonina) inspected and one of the seven vagrant Antarctic fur seals (Arctocephalus gazella) which were found amongst the resident Subantarctic fur seals (A. tropicalis). We also recorded a goose barnacle attached to a Northern rockhopper penguin (Eudyptes chrysocome moseleyi).     

鲁尔泵运行中典型故障分析与处理方法

德国鲁尔泵作为油品外输泵被广泛应用于输油管道泵站。结合现场实践，对运行过程中泵机组因为机械密封动环轴套发生轴向串动而引起的泵机组突然停机、启动时出现堵转的现象进行阐述和分析。从泵机组机械密封的结构设计和受力状态分析入手，阐述了机械密封动环轴套发生位移是由灌泵时巨大的流体冲击力造成的这一观点，并通过建立流体力学模型进行计算证明，最后成功解决了机组运行中的过载停机和启动堵转难题，对于今后鲁尔泵机组类似故障的解决具有借鉴意义。（表1，图7，参7）     

干气密封失效原因分析与有效性措施

针对西气东输站场内压缩机组干气密封频繁失效并造成高额维修更换费用的问题，从干气密封的基本结构和工作原理出发，分析了西气东输管道干气密封实际应用效果，重点剖析了部分压缩机组站场干气密封失效的原因，根据实际生产运行中得出的结论，在收集和分析西气东输各站影响干气密封事件的同时，深入分析了导致干气密封失效的一系列因素，并从压缩机的设计、干气密封系统设计、阻挡密封、干气密封的运输和储藏、安装和拆卸、运行和维护6个方面提出了提高干气密封有效性的针对性措施，以期对压缩机站场干气密封的使用及维护提供指导。（图6，参6）     

谈阳离子乳化沥青稀浆封层的施工工艺

简要介绍了阳离子乳化沥青稀浆封层的施工工艺及施工中应注意的几个问题     

Longitudinal study of northern fur seal (Callorhinus ursinus) hematology

Although the causes have not been specified yet, wild populations of northern fur seals (Callorhinus ursinus) have been decreasing, which is why conservation techniques such as captive breeding and health maintenance should be established. Hematological parameters can be used to maintain the health status of northern fur seals kept in captivity for artificial reproduction and public education. Year-round fluctuations of blood parameters have not been examined for northern fur seals due to the difficulties in obtaining serial blood samples from wild animals during the oceanic migration period from late autumn to spring. In this study, blood samples were collected from four captive northern fur seals and analyzed monthly for more than three years to clarify the seasonal fluctuation patterns in 14 hematological parameters. Many hematological parameters seemed to be seasonal patterns: summer–autumn and winter–spring; leukocyte-related parameters were higher in summer and autumn than in winter and spring; erythrocyte-related parameters were lower in summer and autumn than in winter and spring. Significant seasonal differences in nine of the 14 parameters were observed using a generalized linear mixed model (GLMM) analysis. These results have improved our understanding of the seasonal patterns of hematological characteristics in the northern fur seal and can contribute to the health care of protected or captive northern fur seals.     

森林消防用离心泵机械密封的改进

机械密封性能是影响森林消防用离心泵使用性能的重要因素。分析了森林消防用离心泵机械密封失效的原因,改进了机械密封的结构,这对森林消防用离心泵的可靠性和经济性有重要意义。     

The effect of rehabilitation of northern elephant seals (Mirounga angustirostris) on antimicrobial resistance of commensal Escherichia coli

The aim of this study was to determine if antimicrobial drug use increases resistance of commensal gastrointensinal Escherichia coli of wild northern elephant seals (Mirounga angustirostris) treated in rehabilitation, and, if so, identify the risk factors involved. Minimum inhibitory concentration (MIC) levels of twelve antimicrobial drugs were determined for 289 E. coli isolates from 99 seals sampled at admission and 277 isolates obtained at release from rehabilitation using broth microdilution. Prevalence of E. coli antimicrobial resistance, MIC(50), MIC(90), and clustering of MIC values were determined for seals and the data were analyzed using Fisher's exact test, ordinal logistic regression and negative binomial regression. At release from rehabilitation 77.8% of the seals had antimicrobial resistant E. coli compared to 38.4% of the seals at admission. The MIC(90) for amoxicillin-clavulanic acid, chloramphenicol, enrofloxacin, ticarcillin-clavulanic acid, and trimethoprim-saulfamethoxazole were at levels considered to be sensitive at admission but they increased to levels of resistance at release. E. coli were grouped into four clusters by their MIC values, with increasing levels of resistance going from Cluster 1 to 4. A primary risk factor associated with the probability of a seal having E. coli in Clusters 3 and 4 was time in rehabilitation, regardless of whether the animal received treatment with antimicrobial drugs, suggesting nosocomial infection. The results of this study provide evidence that increased levels of hygiene and appropriate use of antimicrobial therapy might be important in the rehabilitation of wild animals to prevent rise in the prevalence of antimicrobial resistant bacteria.     

截干封蜡技术在造林中的应用

通过对比试验表明，截干封蜡技术可以使造林成活率提高14个百分点。截干封蜡技术是提高造林成活率的有效措施之一。     

Apparent Seroprevalence of Salmonella spp. in Harp Seals in the Greenland Sea as Determined by Enzyme-linked Immunosorbent Assay

An indirect ELISA was developed as a possible tool for surveillance of the seroprevalence of Salmonella spp. in harp seals. This species is hunted for human consumption and thus transmission of disease to humans cannot be excluded. To cover a broad spectrum of serogroups, a mixture of the lipopolysaccharides (LPS) of S. typhimurium and S. choleraesuis was used as the antigen in this pilot study. Chicken anti-harp-seal immunoglobulin horseradish peroxidase conjugate served as the immunoconjugate. Sera from four captive harp seals, which were Salmonella culture-negative and had no clinical or historical evidence of salmonellosis, were used as negative controls. After immunization with an inactivated S. typhimurium vaccine, further sera from these seals were used as positive controls, as no serum from naturally infected animals was available. Serum samples from 93 harp seals caught in the Greenland sea in 1999 were examined, and anti-Salmonella antibodies were found in the samples from two individuals (seroprevalence 2.2%). Although Salmonella has been isolated from other pinniped species, this is the first documentation of Salmonella-seropositive harp seals. This study contributes to the evaluation of the importance of salmonellosis in arctic marine mammals and thus to the prevention of potential outbreaks of this important zoonosis.     

输油泵螺旋密封装置的适应性问题

在Ｄ型输油泵螺旋密封装置的应用中发现,不同规格的Ｄ型泵在输送不同原油及在不同运行工况下,会导致密封效果出现较大差异。通过分析,指出在螺旋密封装置设计时将输送介质粘度、运行温度及压力等参数作为常数,是导致密封效果不理想的主要原因。在实践经验的基础上,根据实际工况,确定了螺旋密封装置的设计参数选值,对原设计进行了修改,在一定程度上提高了螺旋密封装置的适应性。