瞬态电磁脉冲对细胞跨膜电位的影响

我们初步研究了瞬态电磁脉冲的非热生物效应,取得了第一手实验数据,为进一步探索其机理提供基础［１］．低强度瞬态电磁脉冲非热效应的源发点为细胞膜,脉冲对细胞跨膜电位的影响是导致其生物效应的原因之一［２］．所以需要了解电磁脉冲激发的细胞跨膜电位,以及瞬态电磁脉冲特性对跨膜电位的影响．我们采用简化的细胞电学模型计算得到不同特性的瞬态电磁脉冲对细胞跨膜电位的影响,结果具有普遍指导意义．１　简化的细胞电学模型　　在实验系统中,电磁脉冲的频率范围不是很宽,采用的细胞种类也有限,可以统一采用简化的细胞电学模型进…     

低强度瞬态电磁场脉冲作用于不同动物细胞形成电穿孔的实验比较

电穿孔是由电磁脉冲作用引起细胞或生物组膜半通透性暂时或永久性丧失出现穿孔的现象 .目前电穿孔技术已广泛应用于生物技术、基因工程及临床医学等很多领域 ,而其研究多集中于针对单个或数个瞬时高强度脉冲 (电场强度为 10 2 ～ 10 3ｋＶ/ｍ ,脉冲作用时间一般为 10 - 6 ～ 10 - 3ｓ)作用下细胞或组织膜的穿孔现象 ,与此相关的机理分析及实验研究已较为详尽[1～ 4 ] .近 10年来 ,我们一直致力于弱电磁场的非热生物效应的研究 ,并采用电场强度几ｋＶ/ｍ、脉冲宽度几个ｎｓ～ 10 0ｎｓ的低强度瞬态电磁脉冲对生物样品进行照射实验 ,结果发现…     

瞬态电磁脉冲以淋巴细胞遗传及免疫功能的影响

通过以人的T－淋巴细胞为受试对象，以其结合绵羊红细胞形成E－玫瑰花结的百分率为指标，测试了不同波形参数的脉冲电磁场，不同照射时间对E－玫瑰花结形成率的影响；并讨论了瞬态电磁脉冲（TEMP）对长白猪巴细胞转化率等遗传学效应的影响，为解释低强度瞬态电磁脉冲对细胞产生非热效应作用的机理提供了可靠的依据。     

电穿孔——解释生物体中非热生物效应的关键机理

介绍了细胞膜电穿孔的形成过程和基本应用，报道了瞬态电磁脉冲和生物细胞相互作用的一些重要实验结果。采用电穿孔机理解释了细胞膜破裂的原因。     

瞬态电磁脉冲对淋巴细胞遗传及免疫功能的影响

通过以人的 T-淋巴细胞为受试对象 ,以其结合绵羊红细胞形成 E-玫瑰花结的百分率为指标 ,测试了不同波形参数的脉冲电磁场、不同照射时间对 E-玫瑰花结形成率的影响 ;并讨论了瞬态电磁脉冲(TEMP)对长白猪淋巴细胞转化率等遗传学效应的影响 ,为解释低强度瞬态电磁脉冲对细胞产生非热效应作用的机理提供了可靠的依据     

瞬态电磁脉冲对淋巴细胞遗传及免疫功能的影响

通过以人的T-淋巴细胞为受试对象,以其结合绵羊红细胞形成E-玫瑰花结的百分率为指标,测试了不同波形参数的脉冲电磁场、不同照射时间对E-玫瑰花结形成率的影响;并讨论了瞬态电磁脉冲(TEMP)对长白猪淋巴细胞转化率等遗传学效应的影响,为解释低强度瞬态电磁脉冲对细胞产生非热效应作用的机理提供了可靠的依据.     

利用电穿孔提高抗肿瘤药物细胞毒性的初步研究

作者运用电磁脉冲使细胞电穿孔并结合抗肿瘤药物观察细胞的毒性 ,比较了电穿孔组与对照组细胞的抗肿瘤药物胞质毒性的差异 ,发现电穿孔组比对照组的胞质毒性显著提高 .结果说明 ,利用电穿孔可提高抗肿瘤药物的细胞毒性 ,为治疗肿瘤提供了新的途径 .     

低强度瞬态电磁脉冲对淋巴细胞影响的实验研究

从低强度瞬态电磁脉冲对淋巴细胞转化率、T-淋巴细胞免疫能力等影响的实验入手，通过人的T-淋巴细胞为受试对象，以其结合绵羊红细胞形成E-玫瑰花结百分率为指标，测试了不同波形参数的脉冲电磁场、不同照射时间对E-玫瑰花结形成率的影响，为解释低强度脉冲电磁场对细胞产生非热效应作用的机理了可靠的依据。     

低强度瞬态电磁场下动物细胞的电穿孔效应

用低强度瞬态电磁场处理动物细胞后,一些胞内蛋白可以溢出细胞,荧光标记抗体蛋白（ＩｇＧ）可以进入细胞,通过扫描电镜观察到红细胞膜上有电致孔洞,证实了低强度瞬态电磁场作用能起电穿孔。     

瞬态电磁脉冲对细胞增殖的影响

实验采用有丝分裂指数测定法及＾３Ｈ－ＴｄＲ掺入法,研究瞬态电磁脉冲对人外周血淋巴细胞及艾氏腹水癌细胞增殖的影响。结果发现,没有植物凝集素ＰＨＡ时,１００ｋＨｚ和２００ｋＨｚ瞬态电磁脉冲对淋巴细胞有丝分裂指数和＾３Ｈ－ＴｄＲ掺入量无显著影响;有ＰＨＡ时,１００ｋＨｚ瞬态电磁脉冲促进淋巴细胞摄取＾３Ｈ－ＴｄＲ,细胞有丝分裂指数增加,２００ｋＨｚ瞬态电磁脉冲抑制淋巴细胞摄取＾３Ｈ－ＴｄＲ,细胞有丝分裂指     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.