Diversity and Distribution of Host Animal Species of Hantavirus and Risk to Human Health in Jiuhua Mountain Area,China

Objective To investigate the diversity and the distribution of host animal species of hantavirus and the effect on human health in Jiuhua Mountain area,China.Methods The host animal species of hantavirus was surveyed by using the trap method and the species diversity was evaluated by using the Simpson,Shannon-Weaner,and Pielou indices.Hantavirus antigens or antibodies in lung and blood samples of all the captured host animals were detected by direct or indirect immunofluorescence.Results Nine animal species of hantavirus were distributed in the forest ecosystem of Jiuhua Mountain.Of these,Niviventer confucianus and Apodemus agrarius were predominant,and N.confucianus,Rattus norvegicus,and Mus musculus had relatively large niche breadth index values.The host animals in the eastern and western mountain regions shared similar biodiversity index characteristics,predominant species,and species structures.Hantavirus was detected in 5 host animal species in Jiuhua Mountain area,the carriage rate of hantavirus was 6.03%.The average density of host animals in forest areas of the mountainous area was only 2.20%,and the virus infection rate in the healthy population was 2.33%.Conclusion The circulation of hantavirus was low in the forest areas of Jiuhua Mountain and did not pose a threat to human health.

Stable Expression of Hantavirus H8205 Strain G1/IL-2 Gene and Immune Protection of the Fusion Gene

To explore the feasibility of stable expression of Hantavirus H8205 strain G1 segment and human IL-2 fusion gene in Vero cells, and to examine the immune protection effects on mice vaccinated with this recombinant eukaryotic expression vector containing Hantavirus G1 gene and IL-2 gene. With the help of lipofectamine, the Vero cells were transfected with pcDNA3.1/HisB-IL-2-G1 and the positive cells were selected by G418. IFAT and SDS-PAGE elec- trophoresis were used to determine the stable transfection and expression of recombinant protein. Each mouse was inoculated with plasmids intramuscularly （i.m.） three times, 2 boosts were given at 2-week intervals, serum anti-hantavirus antibodies were detected by ELISA and neutralizing antibodies （NAb） were detected by Plaque Reduction Neutralization Test. The fusion protein expressed in Vero cells was 78 kD, corresponding to the estimated molecular size. The neutralizing antibody titers of mice with pcDNA3.1/HisB-IL-2-G1 were 1：20-1：80. IL-2/G1 fusion gene could be transferred in Vero cells and stably express the fusion protein. Specific humeral immune responses in mice can be induced with the recombinant eukaryotic expression vector containing the fusion gene, which lays the foundation for further development of therapeutic HTNV vaccine.

Preparation and antigenic characterization of rat monoclonal antibodies againts Hantavirus

Monoclonal antibodies (McAb) to Hantavirus (HTV)were derived from the hybridoma fused with Lou/c plasmocytoma rat cells (IR983F) and spleen cells from lou/c inbred rat immunized with HTV Chen strain. Eleven cell lines producing monoclonal antibodies direc

First Evidence of Hantavirus in Central Iran as an Emerging Viral Disease

Hantavirus is a zoonosis transmitted from rodents to humans. Asymptomatic infected rodents can secrete hantaviruses in the urine, feces, and saliva. The main route of infection transmission to human is aerosols contaminated with the virus. This study was designed to evaluate the serological and molecular prevalence of hantavirus as an emerging zoonoses disease among street sweepers in Isfahan province, central Iran. Serum samples from 200 street sweepers in healthy condition and those with recent renal failure were tested by ELISA (IgM and IgG). Molecular analysis was subsequently applied for IgM positive cases. From these samples, 9 (4.5%) were positive, of which 2 (22.22%) were positive for both IgM and RT-PCR, while 7 (77.77%) were positive for IgG. The mean age and work experience of the positive cases were 39.7 and 11.5 respectively. According to our observations, all positive cases reported prevalence of rodents in their work place. The logistic regression test showed that the age and work experience were not risk factors for being positive, but prevalence of rodents in work place was a risk factor for being positive, when compared with negative cases. This is the first comprehensive study on the prevalence of hantavirus with positive results coming from Iranian population, which can raise the public awareness for the hantavirus infections as a public health threat.

Detection of Hantavirus gene from peripheral blood of patients with HFRS in Heilongjiang province and the epidemiological significance

The aim of this study is to further understand the genotype of Hantavirus （HV） from peripheral blood of patients with hemorrhagic fever with renal syndrome （HFRS） and the epidemiological significance of this disease in Heilongjiang province in recent years. Thirty-one serum samples of clinically diagnosed patients with HFRS were examined by RT-PCR to decide the genetic subtype. On the basis of infection season, the serum samples were divided into two groups： winter （Nov, 2003--Feb, 2004）, spring and summer （April, 200d--Sep, 2004）. Further analysis was performed in combination with clinical symptoms. It was found that among the total 31 samples, 22 were sero-positive. Among 14 serum samples in winter, 8 were sero-positive, of which 5 cases were of type Ⅰ （Hantaan virus, HTNV） and 3 of type Ⅱ （Seoul virus, SEOV）. Among 17 samples in spring and summer, 14 were sero-positive, of which 5 cases were of type Ⅰ and 9 of type Ⅱ . So it concludes that both of the two types of Hantavirus exist in Heilongjiang. The type Ⅰ is the main pathogen of HFRS in winter, and typeⅡ is the main in spring and summer.

基于HVS和小波变换的零水印数字图像算法

该文在分析了现有数字水印特点的基础上,提出了一种新的水印方法。该算法利用了零水印和小波变换的特性,并根据图像的视觉特性选择合适的水印嵌入点,在此基础上利用零水印实现信息的隐藏,因为零水印利用图像的重要特征来构造水印信息,而不是修改图像的重要特征,因此能够很好地解决水印鲁棒性和不可见性之间的关系。实验证明,该算法抵抗各种攻击的能力是很好的。

一种基于HVS的图像自适应盲水印算法

利用人眼视觉系统对背景亮度和纹理的掩盖特性,对小波变换后的系数进行分类,分类的结果是基于图像特征的。对二值水印图像预处理后,根据分类结果采用不同强度自适应的嵌入水印,嵌入采用奇偶判决法则。水印的提取不需要原始载体图像和原始水印图像。实验结果表明,此算法的不可觉察性很好,并对一些诸如中值滤波、JPEG有损压缩、附加高斯噪声、裁剪等各种图像处理攻击有较强的鲁棒性。

HV/CVD系统Si、SiGe低温掺杂外延

研究了硼烷 (B2 H6 )掺杂锗硅外延和磷烷 (PH3)掺杂硅外延的外延速率和掺杂浓度与掺杂气体流量的关系 .B浓度与 B2 H6 流量基本上成正比例关系 ;生长了 B浓度直至 10 1 9cm- 3的多层阶梯结构 ,各层掺杂浓度均匀 ,过渡区约 2 0 nm,在整个外延层 ,Ge组分 (x=0 .2 0 )均匀而稳定 .PH3掺杂外延速率随 PH3流量增加而逐渐下降 ;P浓度在 PH3流量约为 1.7sccm时达到了峰值 (约 6× 10 1 8cm- 3) .分别按 PH3流量递增和递减的顺序生长了多层结构用以研究 PH3掺杂

应用巢式RT-PCR结合RFLP、SSCP对山东肾综合征出血热病人血清中HV基因检测和分型研究

目的探讨山东肾综合征出血热重疫区病人血清中HV分子生物学特征,同时寻找准确、简便、迅速的HV检测与分型方法,从而为制定防治决策提供科学根据。方法从山东肾综合征出血热重疫区临沂市费县收集病人早期血清,应用巢式RT-PCR对病人血清中的HV进行基因扩增,采用RFLP、SSCP分型,并进行序列测定与分析。结果48份临床和ELISA检测确诊的HFRS病人血清经巢式RT-PCR扩增后,41份阳性,阳性率85.42%。41份阳性标本巢式RT-PCR产物经HindIII、HinfI酶切后,呈现2种不同的RFLP图谱:33份显示与R22株相似的酶切图谱,应属SEOV型;另外8份显示出与HTN76-118株相似的图谱,属HTNV型,这8份HTNV型标本均为10-12月间收集的病人血清。41份阳性标本巢式RT-PCR产物经SSCP分析,亦呈现2种不同的图谱:33份具有与R22株相似的SSCP图谱,应属SEOV型;而另8份则与HTN76-118株具有相似的SSCP图谱,属HTNV型。对部分扩增产物序列采用系统进化树分析也得出类似的结果:sdp1、sdp2、sdp3与HTN型76-118株亲缘关系相近,属同一簇,而sdp22、sdp37与SEOV型Z37、R22株亲缘关系相近,属另外一簇,这与RFLP和SSCP获得的结果相一致。结论山东肾综合征出血热重疫区病人基因型以SEOV型为主,但在秋冬季节也存在HTNV型。巢式RT-PCR结合RFLP、SSCP法可对HV准确分型,而且简便、迅速,适合于大规模流行病学调查。

一种基于离散小波变换和HVS的彩色图像数字水印技术

提出了一种将彩色数字水印嵌入到原始彩色数字图像中的算法，通过将水印多次嵌入到DWT后相应的频段来增强鲁棒性；该算法利用了HVS(Human Visual System)特性，并通过实验得出了水印不同彩色分量(R、G、B)的加权系数，从而使嵌入水印后的图像无主观视觉上的失真。通过实验验证，该算法在对嵌入水印后的图像进行JPEG有损压缩、剪切、不规则色块污染、添加各种噪声处理后，提取出的水印表现出了较好的鲁棒性，且主观视觉失真较小。

基于Hv方法的三轴液压振动系统频响函数估计的研究

三轴液压振动系统是实验室内模拟振动环境的主要设备,其主要功能是精确地复现给定的功率谱和时间历程。振动控制技术是实现这一目标的关键技术,它以频响函数估计为基础。频响函数估计的精度影响控制过程的快速性和稳定性。本文对几种典型的频响函数估计方法进行了分析,针对传统方法精度低且受到矩阵病态条件约束等缺点,应用特征分析与摄动理论构造了一种多入多出的Hv方法,并且应用三轴液压振动系统的实测数据对其进行了检验。结果表明该方法是适用的。

PR方程结合HV混合规则计算HFC/HFC和HFC/HC二元混合物气液相平衡

氢氟烃(HFC)/氢氟烃和氢氟烃/碳氢(HC)混合物是两类重要的制冷工质。采用PR状态方程结合Horon-Vidal(HV)混合规则对7种HFC/HFC和7种HFC/HC二元混合物的气液相平衡性质进行了计算,并与PR状态方程结合van der Waals(vdW)混合规则的计算结果进行了对比。结果表明,HFC/HFC体系组元性质比较接近,非理想性不强,vdW混合规则即可达到较理想计算效果,HV混合规则对计算精度的提升有限;对非理想性较强的HFC/HC体系,vdW混合规则对共沸性质的描述不够理想,HV混合规则可以显著提升相平衡的计算精度。

基于HV分割的精确碰撞检测及其应用

为了实现虚拟加工环境中的精确碰撞检测,采用了HV分割的方法以实现三维物体的自动分割,并且在HV分割后很容易地实现包围盒重构,从而对其进行精确碰撞和干涉检测.对于任意两个在虚拟设计环境中的以任意角度旋转的三维物体,采用HV分割均能精确地检测出它们之间的碰撞.该算法在虚拟车削环境中的应用实例可以说明,该算法与传统的包围盒法相比,可更为准确地实现仿真中的碰撞检测.

一种基于HVS的DWT数字水印算法研究

版权保护和信息隐藏最重要的方法就是数字水印技术.该文提出了一种基于HVS的DWT数字水印算法,该算法充分利用人类视觉特性和离散小波变换特点把图像进行分解,并且将低频子带块按升序排列,能选出最优的嵌入水印系数对,这样就能很好地平衡鲁棒性和水印嵌入透明性.测试结果表明,此算法鲁棒性和透明性都很好,具有广阔的应用空间.

一种基于HVS模型的图像质量信噪比评价方法

从研究人体视觉系统的角度出发,给出了一种基于人体视觉系统HVS模型的客观图像质量评价方法,提出了基于HVS模型的SNR和PSNR评价标准,并给出了对典型图像的评测结果,同时也验证了与主观评价结果的一致性。

用HV谱比法推测银川市区沉积层基底分布特征

在缺乏其他资料的情况下,地脉动常常用做确定地震动对地表介质产生影响效应的简便手段。本文以银川市区为研究对象,根据地震勘探资料有目的的选取5条测线在银川市区进行地脉动观测,观测点共141个。用Nakamura提出的HV谱比法解析观测数据,在给定地下构造剪切波速度(VS)的基础上,由H/V比值曲线中的基本频率推测盆地深层地下构造。通过理论计算进一步验证了解析结果。结合前人地震勘探资料推测了银川市区脉动基本频率分布特征,并给出2D和3D银川市基底构造变化情况,对比分析表明,HV谱比法得到的脉动基本频率值可以反映银川盆地基底变化情况。

基于HVS的小波图像融合新算法

目前的大多数基于小波变换的图像融合算法 ,由于并没有细致考虑人眼的视觉特性 ,因而得到的融合效果有时并不理想。为了提高图像的融合效果 ,提出了一种新的基于人类视觉系统 (HVS)的小波图像融合新算法。该算法充分考虑了人类视觉系统的特点 ,首先在多尺度小波分解的基础上 ,计算出每层每个像素邻域的纹理和边缘亮度相关量 ;然后自适应地求得加权融合系数 ;最后采用多层次迭代法来产生融合图像。实验结果表明 ,该算法不仅能使图像融合结果有较大的改善 ,而且有利于人眼对目标的探测和识别。

一种基于HVS和自适应小波变换的彩色图像水印算法

数字水印技术是实现数字产品产权保护的一种新方法。本文提出了一种基于HVS和自适应小波变换的彩色图像水印改进算法。首先利用改进的自适应小波变换对原始图像进行处理,然后采用混合置乱算法对水印图像进行处理。同时根据HVS的特点来确定水印的嵌入强度。实验证明这种算法具有较好的隐蔽性,对各种图像处理操作是鲁棒的。

一种基于HVS特性的视频质量评测方法

本文针对视频质量的评测应用,对传统峰值信噪比(PSNR)算法加以改进。通过在视频帧内图像和帧间图像的处理过程中引入人眼视觉系统(HVS)的主要特性,克服传统PSNR算法在序列质量检测应用方面的缺陷。方法在帧内图像处理上利用人眼对边缘轮廓失真具有较强敏感性的特点,设计了基于图像边缘的检测方案以提高对典型空域失真的检测性能;在帧间图像处理上,通过测量帧间时域能量的变化,获得序列在时域轴上的典型特征,并据此对空域检测结果进行修正。通过上述改进,算法能在保持传统PSNR算法简易性的同时,提升其检测结果与主观感受的相关性;同时算法的计算量并不复杂。

从鼠、螨(革螨、恙螨)和人中分离HV的基因分型研究

目的 了解鼠、螨 (革螨、恙螨 )、人间HV基因型是否一致。方法 对从同一疫区鼠、螨、人中分离的HV进行毒力测定 ;单克隆抗体检测和多聚酶链式反应 (PCR)进行基因分型。结果 从同一疫区鼠、螨、人中所分离的HV毒力和单克隆抗体检测均有I型 (HV型 )反应特征。进一步用PCR扩增鉴定 ,表明从鼠、螨、人中所分离的HV其基因型一致。结论 从同一疫区鼠、螨 (革螨、恙螨 )、人中所分离的HV其基因型一致 ,并构成三者相互传播关系 。