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971.
A comparison is made between a hot-spot model and a recently proposed oblate spheroid model (Böhm-Vitense & Van Dyk 1987) to explain the spectroscopic and photometric variations of α2 CVn. It is found that the spot model gives a better fit to the spectroscopic and photometric variations. The spot model requires five high temperature circular patches over the surface of the star. The positions of these patches agree well with those derived spectroscopically by Pyper (1969). 相似文献
972.
Xueyi YOU 《中国地球化学学报》2006,25(B08):111-111
With the densification of population and the deterioration of urban ecological cycle, the airborne disease virus is becoming a new crisis for human. It is well known that airborne disease virus such as smallpox, hives, mumps and SARS can cause respiratory disease by the aerosol of sneezes or cough of infected person. The pathogens release virus aerosol to the environment. If the virus can live some time in the air, it can go with air flowing far away. The aim of the present research is to simulate the transportation of airborne disease virus in a group of buildings by taking into account the time-dependent virus aerosol source. A commonly used virus-host dynamical model is introduced to simulate the time-dependent development of virus aerosol releasing process. The wind velocity field is described by the continuity equation, momentum equation and turbulence model to enclose the Reynolds stress in the momentum equation. The RNG model is used in all simulations. The aerosol of microbial pollutant is assumed flowing at the same velocity as the air. The computation time is one life cycle of virus T. We assume that the pathogens release virus aerosol at the upper wall of building A. The conclusions are： （1） The microbial pollutant begins to be discharged after its delitescence 1/12 T. As the virus goes into logarithmic growth period, the concentration of virus and the pathogenic area increase very fast. After entering the virus decay period （1/3 T）, the pathogenic area decreases. It should be noticed that no secondary infection is considered in present simulation. Generally, as the virus concentration is above the pathogenic concentration, new pathogens will be infected and release virus aerosol to the environment. With the increase of new pathogens, the pathogenic area would increase very fast and finally result in the outbreak of infection. 相似文献
973.
简要介绍了浙江省突发性地热点基本情况、产出特征、成因机制,同时还介绍了一处运用地热物化探方法勘查突发性地热点的实例,指出突发性地热点分布区密集出现多处地热点及地热异常点,潜在地热资源量丰富,且多依托重要城市分布,开发利用条件好,是省内最具开发前景的地热远景区。 相似文献
974.
975.
中国的就地城镇化被视为城乡界限淡化条件下人类聚落系统发生重大改变的证据之一。已有文献大多局限在城乡二元分析框架内,本文基于城乡界限淡化的背景建立县域就地城镇化模型,对河南省108个县市2006—2016年就地城镇化水平的整体格局、空间聚类和热点区域演化进行分析。研究结果显示：① 河南省大多数县市就地城镇化水平有了明显提升,但大部分县市仍处低水平发展阶段,就地城镇化水平相对差异呈扩大趋势。② 河南省就地城镇化空间演化特征明显,“L”形豫北-豫东板块就地城镇化先行区凸显,豫西整体城镇化水平虽低但发展后劲足,连片发展态势明显。③ 河南省县域就地城镇化全局自相关性十分显著,空间聚集倾向和空间近邻效应日益显现,但仅出现了小范围的高聚类区和低聚类区。④ 河南省县域就地城镇化的热点区、冷点区分布格局变化较大,但次冷区和次热区基本保持稳定状态。⑤ 基于极大似然估计的实证检验结果表明,基础设施建设水平、城镇就业规模、人口规模和财政支出水平等是影响河南省县域就地城镇化水平的重要因素。基于上述研究结论,本文提出应从加快推进户籍制度和就业创业制度改革、完善农业土地流转和征地补偿制度、加快城乡结合部新型农村社区建设等方面提升就地城镇化建设质量和水平。 相似文献
976.
977.
978.
The ovary is an excellent system for studying stem cell renewal and differentiation, which is under the control of ovarian somatic cells. In order to understand oogenesis in Fugu rubripes (Temminck et. Schlegel) as a marine fish model of aquaculture importance, we established cell lines called TSOC1 and TSOC2 from a juvenile ovary of this organism. TSOC1 is composed of spindle epithelial-like cells, while the other is cobblestone-like cells. Therefore, TSOC1 and TSOC2 appear to consist of ovarian somatic cells. Growth requirement condition was investigated including temperature, concentration of FBS and pH. Significant fluorescent signals were observed after TSOC1 and TSOC2 cells were transfected with pEGFP-N3 vector, indicating its potential utility for genetic manipulation such as gene function studies. It is shown that these cell lines are effective for infection by the turbot reddish body iridovirus and flounder lymphosystis disease virus as evidenced by the appearance of cytopathic effect and virus propagation in the virus-infected cells, and most convincingly, the observation of viral particles by electron microscopy, demonstrating that TSOC1 and TSOC2 are suitable to study interactions between virus and host cells. It is believed that TSOC1 and TSOC2 will be useful tools to study sex-related events and interactions between primordial germ cells and oogonia cells during oogenesis. Therefore, establishment of ovary cell lines from Fugu rubripes seems to be significant for those research areas. 相似文献
979.
中医学之郁证,涵盖了现代医学之“抑郁症”。对该病的认知与调治,已成为心身医学高度重视和共同攻克的重大课题。国医大师孙光荣教授认为,中医心身医学认知郁证的源泉是“天人合一”观;而中医调治郁证必须遵循“形神合一”观。孙老认为,中医临床必须具备3个基本思维：四诊审证、审证求因的“求解思维”,求因明机、明机立法的“上升思维”,立法组方、组方用药的“决断思维”。因此,中医心身医学的医、护、药工作者,在郁证的调治过程中首先要注重以“神形”为主线,把握20个“天”“人”元素,运用“求解思维”“上升思维”进行心身疾病的辨证,并做到“五注重”,方可达到事半功倍的良好效果。 相似文献
980.
基于数字足迹的河南省A级景区旅游流网络特征研究 总被引：1，自引：0，他引：1
以携程旅行网站上发布的关于河南省景区旅行游记作为数据来源,运用社会网络分析和空间分析方法分析河南省A级景区空间网络特征。结果表明:河南省A级景区旅游流网络中4A级及以上资源禀赋较高的景区与其他景区联系频繁,客流量最多的景区主要分布在洛阳、郑州、开封和焦作;龙门石窟、嵩山少林寺、白马寺、香严寺、云台山-神农山-青天河景区、万仙山风景区6个景区的节点中心性和结构洞分析排名靠前,资源优势显著,旅游吸引力较强,竞争优势明显,位于网络的核心地位;河南省A级景区网络整体规模大但密度低,核心-边缘结构明显,核心节点对边缘节点的带动作用不强,凝聚子群在郑、汴、洛地区呈现集聚发展趋势,整体网络具有一定的流通性和集聚性,呈现小世界网络特征。 相似文献