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171.
172.
Andréia Dalla Vecchia Mariana Kluge Joseane V. dos Santos da Silva Juliana Comerlato Manoela T. Rodrigues Juliane D. Fleck Roger B. da Luz Thais F. Teixeira Paulo M. Roehe Roberta Capalonga Ana Beatriz Oliveira Fernando R. Spilki 《Food and environmental virology》2013,5(1):41-45
Torque teno virus (TTV) was surveyed in tap water collected in schools from three municipalities located in the south of Brazil. TTV genomes were found in 11.7 % (4/34) of the samples. TTV DNA was detected in 10.5 % (2/19) of the samples collected at the city of Caxias do Sul and in 25 % (2/8) of the samples from Pelotas. Those cities have a low rate of sewage treatment. All samples from Santa Cruz do Sul, which has nearly 92 % of its sewage treated, were negative. These results suggest that the amount of sewage treated may have an effect on the detection rates of TTV DNA in drinking water in a given urban area, showing a mild negative correlation (r = ?0.76), when comparing the percentage of sewage treatment to the detection of TTV genomes. The detection rate of TTV was also compared with Escherichia coli, showing a strong correlation (r = 0.97), indicating that TTV may be a suitable marker of fecal contamination. 相似文献
173.
目的:了解石油管道储运员工的心理健康现状,建立管道储运员工症状自评量表(SCL-90)的群体常模。方法:运用整群抽样方法和症状自评量表(SCL-90)对5544名中国石化管道储运公司员工进行心理健康状况调查,将SCL-90结果与中国常模比较。结果:本次调查心理健康状况好3947人,占71.2%;心理健康状况良好1299人,占23.4%;心理健康状况一般238人,占4.3%;心理健康状况异常60人,占1.1%;石化管道储运员工在躯体化、焦虑、精神病性、阳性项目数均分显著高于全国常模;人际关系、敌对、偏执和精神病性因子均分男性显著高于女性,恐怖因子均分女性显著高于男性;35岁及以上组的躯体化、强迫、抑郁、焦虑、敌对、恐怖、精神病性以及阳性项目数的因子均分均高于35岁以下组;大专组和高中及以下组各项因子均分均显著高于本科及以上组。结论:管道储运员工心理健康状况低于一般人群。年龄相对较大以及学历相对较低员工的心理健康状况是企业关注的重点。 相似文献
174.
175.
地震海啸危险性分析研究进展 总被引:1,自引:0,他引:1
本文追溯地震海啸危险性分析研究的兴起与发展,介绍地震海啸危险性分析的原理和方法,综述地震海啸危险性分析的常用工具———地震海啸数值模式的研究进展,讨论目前地震海啸危险性分析研究中存在的主要困难和问题。指出建立地震海啸危险性分析不确定性的定性分析和定量评估方法,进行地震海啸危险性分析的不确定性评估,应是今后的一个重要研究方向。 相似文献
176.
177.
黄河入河沙漠颗粒物对磷酸盐的吸附特征 总被引:1,自引:0,他引:1
研究了黄河入河沙漠颗粒物在天然水(河水和海水)中对磷酸盐的吸附行为,用改进的Langmuir和Freundlich等温吸附模型对实验数据进行了拟合.结果表明,①改进的Langmuir等温吸附模型更适用于描述黄河入河沙漠颗粒物对磷酸盐的吸附特征,其物理意义更明确,得到的拟合参数更合理;②颗粒物对磷的最大吸附容量Qmax变化范围为41.322~357.143mg.kg-1,其中居延海颗粒物Y2的Qmax最大.Qmax与颗粒物(Y1~Y5)的有机质有着极显著的正相关关系;③除巴丹吉林沙漠颗粒物Y1外,颗粒物的临界磷平衡浓度EPC0值均大于其相应水体的磷浓度.Y1在黄河水中吸附磷的EPC0小于相应水体的磷浓度0.0100.053 mg.L-1,而在渤海海水中却大于相应水体的磷浓度0.1090.074 mg.L-1,表明Y1吸附了黄河水中的磷,进入渤海后Y1原有吸附可交换态磷NAP转移到海水中.其它颗粒物与相应水体进行磷交换的过程中存在着解吸磷的现象,具有向相应水体释放磷的能力;④黄河入河沙漠颗粒物对磷酸盐的吸附等温线是过溶液浓度轴0.00的交叉型等温线,这种新型交叉型吸附-解吸模型较好地解释了其吸附特征和天然粒子的双重性作用. 相似文献
178.
INTRODUCTION: The study reported here was designed to test the ability of the theory of planned behavior to mediate the effect of parental supervision on adolescents' intentions to violate driving rules. METHOD: A representative sample of 1,654 adolescents completed questionnaires during individual and anonymous interviews carried out at their schools. RESULTS: Results showed that age, gender, prior risky driving-behavior, and parental supervision significantly predict intentions to violate driving rules. Attitude and the subjective norm partially mediate the effect of age, prior behavior, and parental supervision. Perceived behavioral control does not predict intention and is not predicted by other variables. IMPACT: The results suggest that social cognitive variables partially mediate the effect of parenting practices such as supervision. 相似文献
179.
Although Asia is thought to have played a critical role in the radiation of artiodactyls, the fossil record of stem selenodonts
(“dichobunoids”) remains dramatically poor in tropical Asian regions. In this study, we report a new dichobunid genus and
species Cadutherium kyaukmagyii and a new basal ruminant genus and species Irrawadymeryx pondaungi, from the late Middle Eocene Pondaung Formation, Central Myanmar. Although the scarcity of the present material prevents
any attempts to investigate the phylogenetic relationships of Cadutherium with contemporaneous forms from other Holarctic landmasses, this new form shed new light on the diversity of these small
rabbit-like ungulates during a key period of their evolutionary history. Reexamination of the small-bodied artiodactyls from
Pondaung leads us to propose new identifications of certain published specimens and, in turn, to investigate the temporal
and geographic distribution of taxa recognized in the Pondaung Formation. Although fragmentary, these potential new taxa reveal
an unsuspected diversity of small forms among artiodactyls of Pondaung. This addition to the Eocene record of dichobunoids
and early ruminants provides further insight in the diversity of dental patterns among small artiodactyls from the Pondaung
Formation and attests to the antiquity of these groups in Southeast Asia. 相似文献
180.
Power matters in closing the phenotyping gap 总被引:1,自引:0,他引:1
Meyer CW Elvert R Scherag A Ehrhardt N Gailus-Durner V Fuchs H Schäfer H Hrabé de Angelis M Heldmaier G Klingenspor M 《Die Naturwissenschaften》2007,94(5):401-406
Much of our understanding of physiology and metabolism is derived from investigating mouse mutants and transgenic mice, and
open-access platforms for standardized mouse phenotyping such as the German Mouse Clinic (GMC) are currently viewed as one
powerful tool for identifying novel gene-function relationships. Phenotyping or phenotypic screening involves the comparison of wild-type control mice with their mutant or transgenic littermates. In our study, we explored
the extent to which standardized phenotyping will succeed in detecting biologically relevant phenotypic differences in mice
generated and provided by different collaborators. We analyzed quantitative metabolic data (body mass, energy intake, and
energy metabolized) collected at the GMC under the current workflow, and used them for statistical power considerations. Our
results demonstrate that there is substantial variability in these parameters among lines of wild-type C57BL/6 (B6) mice from
different sources. Given this variable background noise in mice that serve as controls, subtle phenotypes in mutant or transgenic
littermates may be overlooked. Furthermore, a phenotype observed in one cohort of a mutant line may not be reproducible (to
the same extent) in mice coming from a different environment or supplier. In the light of these constraints, we encourage
researchers to incorporate information on intrastrain variability into future study planning, or to perform advanced hierarchical
analyses. Both will ultimately improve the detectability of novel phenotypes by phenotypic screening.
Carola W. Meyer and Ralf Elvert contributed equally to this work. 相似文献