检索结果-南通市图书馆

2014—2016年济南市哨点医院食源性诺如病毒感染病例流行病学特征分析

在线全文

学校读者我要写书评

暂无评论

中国食品卫生杂志 2018年第3期30卷 264-269页

作者：杨丽段德水孙婷刘守钦孙延斌济南市疾病预防控制中心山东济南250021

目的了解济南市哨点医院食源性散发腹泻病例中诺如病毒感染类型以及流行病学状况和临床特征。方法采集2014年1月—2016年12月济南市2家食源性疾病主动监测哨点医院的腹泻病例粪便标本,并收集病例的临床症状资料和流行病学资料。结果共收... 详细信息

目的了解济南市哨点医院食源性散发腹泻病例中诺如病毒感染类型以及流行病学状况和临床特征。方法采集2014年1月—2016年12月济南市2家食源性疾病主动监测哨点医院的腹泻病例粪便标本,并收集病例的临床症状资料和流行病学资料。结果共收集1 292份病例标本,诺如病毒阳性率为18.58%(240/1 292),其中GII基因型占75.42%(181/240)。不同性别的诺如病毒感染病例以及GI和GII基因型病例阳性率差异均无统计学意义(P>0.05);2种基因型各年龄段阳性率差异有统计学意义(χ2=27.912,P<0.001;χ2=42.285,P<0.001)。第一和第四季度诺如病毒阳性率高于其他季度,具有季节性分布特点。240例诺如病毒阳性病例中以单纯腹泻症状为主(54.17%,130/240),其次为腹泻+呕吐症状(18.75%,45/240);腹泻强度以中度腹泻为主(38.75%,93/240),平均腹泻频次为5.82次/d,粪便性状均以水样便为主(93.75%,225/240)。诺如病毒阳性病例出现呕吐症状的比例为30.00%(72/240),呕吐频次以1~2次/d居多。可疑暴露食物种类以肉与肉制品所占比例最高,其次为水产动物及其制品和乳及乳制品,占比分别为20.00%(48/240)、18.33%(44/240)和15.00%(36/240)。结论济南市食源性散发腹泻病例诺如病毒感染类型以GII基因型为主,全年流行且具有明显的季节性,婴幼儿为易感人群。应针对诺如病毒感染的季节性特点,以及暴露人群易感程度的差异和暴露食品种类不同的特点,加强食源性散发腹泻病例的监测、识别和防控。

关键词：食源性疾病诺如病毒基因型临床症状流行病学特征易感人群婴幼儿济南

2013-2016年济南市哨点医院食源性疾病病原体分布及流行特征调查

在线全文

学校读者我要写书评

暂无评论

中华疾病控制杂志 2018年第3期22卷 282-286页

作者：杨丽段德水钟庆孙婷董淑香李世凯刘守钦孙延斌济南市疾病预防控制中心食品安全风险监测所山东济南250021

目的了解济南市食源性疾病病原体分布特征,为防控食源性疾病提供依据。方法对济南市2013-2016年两家食源性疾病哨点医院上报采集的1 730例病例标本进行检测分析。结果食源性疾病致病原检出率为37.34%。其中,细菌感染检出率为19.31%,以... 详细信息

目的了解济南市食源性疾病病原体分布特征,为防控食源性疾病提供依据。方法对济南市2013-2016年两家食源性疾病哨点医院上报采集的1 730例病例标本进行检测分析。结果食源性疾病致病原检出率为37.34%。其中,细菌感染检出率为19.31%,以肠集聚性大肠埃希菌(enteroaggregative escherichia col,EAEC)为主;诺如病毒感染检出率为14.05%,以GⅡ基因型感染为主;多重感染检出率为3.99%。不同年份(X^2=33.19,P<0.001)、不同性别(X^2=12.09,P=0.001)间病原检出率差异均有统计学意义。食源性疾病发病冬季以病毒感染为主,夏季以细菌感染为主。患者年龄分布以18~35岁年龄段(50.00%)为主。可疑暴露食品居前三位的分别为乳及乳制品(18.89%)、肉及肉制品(17.49%)和水产动物及其制品(13.62%)。多重感染的可疑暴露食品主要为肉及其制品(17.39%)和水产动物及其制品(17.39%)。结论夏秋季主要致病菌为EAEC,冬季以GⅡ基因型感染为主,提示应根据季节变化趋势,针对不同暴露人群和暴露食品,制定相适应的食源性疾病防控措施。

关键词：病原人群监测流行病学

1起沙门菌污染肉制品引起的食源性疾病暴发调查

在线全文

学校读者我要写书评

暂无评论

预防医学论坛 2018年第11期24卷 846-848页

作者：杨丽张民段德水于瑞洪钟庆孙延斌济南市疾病预防控制中心山东济南250021 平阴县疾病预防控制中心山东平阴250400

目的查明本次食源性疾病暴发的原因和可疑危险因素,控制暴发的扩散和蔓延。方法结合病例临床特征,发病时间和用餐时间查找可疑餐次,采集可疑食物和病例样本等进行实验室检测。结果共确认29例病例,症状主要为腹泻、腹痛、发热、呕吐,部... 详细信息

目的查明本次食源性疾病暴发的原因和可疑危险因素,控制暴发的扩散和蔓延。方法结合病例临床特征,发病时间和用餐时间查找可疑餐次,采集可疑食物和病例样本等进行实验室检测。结果共确认29例病例,症状主要为腹泻、腹痛、发热、呕吐,部分病例伴头痛、恶心、头晕等。中毒餐次为2017年9月14、15日的午餐和晚餐,中毒食品为熟食肉制品,致病因子为鼠伤寒沙门菌。结论此次食源性疾病暴发是由鼠伤寒沙门菌引起的,交叉污染是鼠伤寒沙门菌污染来源最重要的传播方式。

关键词：鼠伤寒沙门菌食源性疾病暴发流行病学调查

Study on the Method of Soil Productivity Assessment in Black Soil Region of Northeast China

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2009年第4期8卷 472-481页

作者： duan Xing-wu XIE Yun FENG Yan-jie YIN shui-qing State Key Laboratory of Earth Surface Processes and Resource Ecology School of Geography Beijing Normal University Beijing 100875P.R. China

The objective of this paper is to investigate a simple and practical method for soil productivity assessment in the black soil region of Northeast China. Firstly, eight kinds of physicochemical properties for each of 120 soil samples collected from 25 black soil profiles were analyzed using cluster and correlation analysis. Subsequently, parameter indices were calculated using physicochemical properties. Finally, a modified productivity index （MPI） model were developed and validated. The results showed that the suitable parameters for soil productivity assessment in black soil region of Northeast China were soil available water, soil pH, clay content, and organic matter content. Compared with original productivity index （PI） model, MPI model added clay content and organic matter content in parameters while omitted bulk density. Simulation results of original PI model and MPI model were compared using crop yield of land block where investigated soil profiles were located. MPI model was proven to perform better with a higher significant correlation with maize yield. The correlation equation between MPI and yield was： Y= 3.2002Ln（MP/）＋ 10.056, R^2 = 0.7564. The results showed that MPI model was an effective and practical method to assess soil productivity in the research area.

关键词： PI MPI soil productivity black soil region of Northeast China

Uncertainty relation of successive measurements based on Wigner-Yanase skew information

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2022年第1期74卷 25-30页

作者： Jun Zhang Jia-Ning Wei Zhou-Bo duan Kan He Chang-shui Yu College of Data Science Taiyuan University of TechnologyTaiyuan 030024China College of Mathematics Institute of MathematicsTaiyuan University of TechnologyTaiyuan 030024China School of Physics Dalian University of TechnologyDalian 116024China

Wigner-Yanase skew information could quantify the quantum uncertainty of the observables that are not commuting with a conserved *** present the uncertainty principle for two successive projective measurements in terms of Wigner-Yanase skew information based on a single quantum *** could capture the incompatibility of the observables,*** lower bound can be nontrivial for the observables that are incompatible with the state of the quanaim ***,the lower bound is also constrained by the quantum Fisher *** addition,we find the complementarity relation between the uncertainties of the observable which operated on the quantum state and the other observable that performed on the post-measured quantum state and the uncertainties formed by the non-degenerate quantum observables performed on the quantum state,respectively.

关键词： quantum uncertainty relation successive measurements Wigner-Yanase skew information

Effects of Mixing Volume and Initial Particle Size Distribution of Fly Ash on Pore Solution of Cement Paste

在线全文

学校读者我要写书评

暂无评论

武汉理工大学学报 2010年第17期32卷 112-116页

作者： shui Z H duan P SHEN C H School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Center of Materials Research and Analysis Wuhan University of TechnologyWuhan 430070China

The effects of fly ash with different mixing volume and different particle sizes on pore solution of cement-based materials were studied. The pore solution was extracted by squeezing at scheduled ages. The particle size distribution of fly ash was classified as smaller than 45 μm and 45～80 μm,and the mixing volume was classified as 10% and 20%. The concentrations of K+,Na+ and Ca2+ were measured using Inductively Coupled Plasma Emission Spectrometer (ICP),and the pH was measured by acid-base titration. The results indicate that the concentrations of various ions were prompted at the initial time of the hydration. With further hydration,ion concentrations of K+ and Na+ raise again and finally stabilized,but there is a certain decline on Ca2+ later on. It also shows that fly ash exhibited great effect on the hydration of cement,it can lower the concentration of Ca2+ and pH of the pore solution,but raise the concentrations of K+ and Na+. More importantly,ion concentrations of K+,Na+ and Ca2+ reduced with smaller particle sizes of fly ash.

关键词： cement-based materials pore solution ion concentration squeeze

Effect of interface morphology on the mechanical properties of titanium clad steel plates

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 404-408页

作者： Ji-xiong Liu Ai-min Zhao Hai-tao Jiang Di Tang Xiao-ge duan Heng-yong shui Research Institute of Metallurgy Engineering University of Science and Technology BeijingBeijing 100083China

Interface morphology has important influence on the bond quality of titanium clad steel plates. The mechanical properties of titanium clad steel plates with wavy and straight interfaces were investigated by tensile-shear tests and bending tests. The interface morphology of the plates was examined by optical microscopy （OM） and scanning electron microscopy （SEM）. The experimental results show that the shear strength of a wavy interface is higher than that of a straight interface. A wavy interface is the guarantee for obtaining high shear strength to provide a greater shear resistance. During the maerobending process, cracks appear in the swirl of the wave tip and ferrotitanium intermetallies. For in-situ observing the bending process by SEM, the wave tip of a wavy interface and the massive ferrotitartium intermetallies of a straight interface are places where cracks initiate and propagate. The results are the same as those observed in the macrobending process. Became of high hardness, the wave tip and the massive ferrotitanium intermetallies are hard in terms of compatible deformation.

关键词： clad metals cladding titanium low carbon steel interfaces morphology mechanical properties

Variation of alpine lakes from 1986 to 2019 in the Headwater Area of the Yellow River,Tibetan Plateau using Google Earth Engine

在线全文

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2020年第1期11卷 11-21页

作者： LUO Dong-Liang JIN Hui-Jun DU He-Qiang LI Chao MA Qiang duan shui-Qiang LI Guo-Shuai State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China School of Civil Engineering Northeast Forestry UniversityHarbin150040China Key Laboratory of desert and desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Faculty of Geomatics Lanzhou Jiaotong UniverisityLanzhou730070China University of Chinese Academy of Sciences Beijing100049China Hydrology and Water Resources Bureau of Qinghai Province Xining810001China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing100101China Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing100101China

To understand the variations in surface water associated with changes in air temperature,precipitation,and permafrost in the Headwater Area of the Yellow River(HAYR),we studied the dynamics of alpine lakes larger than 0.01 km^2 during 1986-2019 using Google Earth Engine(GEE)*** surface areas of water bodies in the HAYR were processed using mass remote sensing images consisting of Landsat TM/ETM-H/OLI,Sentinel-2A,and MODIS based on automatic extraction of water indices under ***,the lake ice phenology of the Sister Lakes(the Gyaring Lake and the Ngoring Lake)was derived by threshold segmenting of water/ice area *** demonstrate that the change of surface areas experienced four stages:decreasing during 1986-2004,increasing during 2004-2012,decreasing again during 2012-2017,and increasing again during ***,the number of small lakes decreased(-26.5 per year),increased(139.5 per year),again decreased(-109.0 per year),and again increased(433.0 per year).Eight lakes larger than 1 km^2 disappeared in 2004 but restored *** overall trends in the area of small lakes(0.01-1 km^2),large lakes(>1 km^2),and all lakes during 1986-2019 were 0.4,3.1,and 3.4 km^2 per year,*** the onsets of freezing,freeze-up,breaking and the break-up of the Sister Lakes varied from year to year,there is no obvious trend regarding the lake ice *** of lake variations in the HAYR are primarily related to the increased net precipitation and the declined aridity,followed by the construction of hydropower station around the outlet of the Ngoring Lake,as well as permafrost degradation.

关键词： Headwater Area of the Yellow River Lake surface area Lake ice phenology Climate change Google Earth Engine Permafrost degradation

Changes of surface water pollution of Suzhou region: a case study in Taicang County, China

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 1998年第3期10卷 27-35页

作者： Li Yong Xu Rui-wei Zhang shui-ming An Qiong Jin Wei duan Zeng qiang Xi Hui-lin Institute of Soil Science Chinese Academy of SciencesNanjing 210008China Taicang Branch of National EPA Taicang 215400China

Environmental pollution is a by product of industrialization when economy of a region is developing. China also suffers from such a problem, especially in the southern part like Suzhou region in Jiangsu Province. In this paper, data covering situations of surface water pollution and social and economic development showed that the surface water pollution in Taicang County, a typical economic zone of Suzhou region, is significantly correlated to the economic growth of this region.

关键词： environmental pollution economy development surface water Taicang County.