The Expression of VacA in BCF of Helicobacter Pylori and Its Relationship to Vacuolated Effect

Summary: The vacuolated effect of Helicobacter (H. pylori) and its relationship to vacuolated cytotoxin antigen (VacA) were investigated by the method of cytotoxic test and SDS-pobyacrylamide gel electrophoresis (SDS-PAGE). Of the 62 clinical isolates, the broth culture filter (BCF) of 43 strains caused the Vero cell intracytoplasmically vacuolated. H. pylori strains were divided into H. pylori (Toxin +) group with vacuolated effect and H. pylori (Toxin -) group without vacuolated effect. The analysis of the BCF of H. pylori (Toxin +) and that of H. pylori (Toxin -) was studied by SDS-PAGE and Scan reader. A kind of protein with 87 ku molecular weight was recognized in the BCF of 30.23 % (13/43) H. pylori (Toxin +) strains but in none of that of H. pylori (Toxin -) strains, the difference was statistically significant (P<0.05). There was a significant and concordant relationship between OD of the protein band with 87 ku molecular weight and titer of vacuolated activity of H. pylori(Toxin +) (r=0.67 and P<0.05 by linear regression analysis). H. pylori strains were divided into H. pylori (Toxin +) group with vacuolated effect and H. pylori (Toxin -) group without vacuolated effect. The vacuolated effect of H. pylori (Toxin +) was caused by the protein with 87 ku molecular weight (VacA)

一种自适应图象水印算法

数字水印作为数字媒体版权保护的有效办法，近年来在国际上引起了人们极大的兴趣与注意．提出了一个利用块分类的自适应图象水印算法．为了实现自适应，将原始图象分块并设计了一个基于视觉掩蔽特性的分类器．根据分类的结果，不同强度的水印分量被嵌入到不同图象块的ＤＣＴ低频系数中．实验结果表明，应用所提出的算法实现的水印对常见图象处理和噪声干扰具有很好的稳健性．

创面修复中外源性FN对NO的调节作用

目的:探讨外源性FN对内源性NO的调节作用,研究FN在加速感染创面修复中的作用机制。方法:家兔40只随机分成4组,FN组、中药组、FN+中药组和凡士林对照组,在家兔背部制各4cm直径感染创面模型,分别在术前和术后4、7、14、21d,采用改良的NO检测技术,测定血浆和创面渗出液中NO的动态变化。结果:创伤4d时,FN组、FN+中药组渗出液中NO水平高于其它各组(P<0.05),而14d时对照组NO水平升高最显著(P<0.05)。结论:提示FN可调控NO的分泌和释放,对促进感染创面的修复起重要作用。

流体传动及控制的现状及新发展

史维祥教授撰写:“流体传动及控制的现状及新发展”的论文,包括三大部分内容:1、概述;2、流体传动及控制几个重要方面的发展状况;3、液压技术应用中的一些新发展,全文约4.2万字,有很大的参考价值,本刊将分几期陆续刊登。

Production of high strength Al-Zn-Mg-Cu alloys by spray forming process

High strength Al Zn Mg Cu alloys were produced by spray forming process, and compacted by hot extrusion. The results show that the as deposited billets have fine grained microstructure and low porosity. After heat treatment, mechanical properties increase greatly: tensile strength up to 754 MPa, yield strength up to 722 MPa, fracture elongation up to 8%, and elastic modulus up to 72 GPa, respectively. [

Physicochemistry and Mineralogy of Storm Dust and Dust Sediment in Northern China

Dust sediments collected from 1995 to 1998 in Beijing, Dunhuang, Inner Mongolia, Kashi, the Kunlun Mountains, Lanzhou, Ningxia, the Taklimakan Desert, and Xi’an, China, were characterized in terms of their physical, chemical, and mineralogical properties. Most aerosols and dust analysed ranged in texture from silty clay to clay loam. Their median particle diameters (Mds) generally ranged between 5 to 63 μm, coinciding with those of loess from central China and the finest sand from northwestern China. The dust sediments were characterized by a predominance of SiO2 and Al2O3, followed by K2O. Their SiO2/Al2O3 and K2O/SiO2 molar ratios ranged from 5.17 to 8.43 and from 0.009 to 0.0368, respectively. The mass concentration spectrum during a dust storm showed a single peak, rather than the triple peak generally observed under clear sky conditions. The dominant minerals were chlorite, illite, calcite, and dolomite. These physical, chemical, and mineralogical properties were consistent with those of aeolian soils and loess in western and central China. The results suggest that aerosols and fine-grained fractions of dust sediments collected in northern China are mainly composed of soil material transported from the arid and semiarid regions of China and Mongolia by prevailing winds. The rate of deposition and properties of dust falling on eastern China were strongly influenced by meteorological conditions, season, latitude, longitude, and altitude of the sampling sites.

Application of observed strain steps to the study of remote earthquake stress triggering

A study of the Kunlunshan earthquake of MS = 8.1 based on observed coseismic strain steps from the borehole strain monitoring network over China has been carried out with some interesting results. Firstly, many recordings disagree with theoretic calculation using static dislocation model. Secondly, abnormally large strain steps are ob-served at quite a few stations in the tectonically active east-northern China, while in the relatively inactive east-southern China no obvious steps are recorded. It is inferred that seismic stress triggering may significantly affect remote seismic strain field. In other words, whether remote faulting be seismically triggered or not may de-termine the pattern of local seismic strain changes. Further comparison study results of March 11, 1999 Zhangbei earthquake and November 1, 1999 Datong earthquake show that the specific pattern of seismic zones has obvious influence on seismic strain changes in the region. This supports the idea that observed abnormal strain steps might be produced by coseismicly stress-triggered local faulting.

Study on Luster of Fabrics with Goniophotometric Curves

The distribution of the light reflected from various fabric surfaces was studied. A series of samples of different fibers, weaves and colors were investigated. The experiments show that the goniophotometric curves of fabrics change with constituent fibers, weave, dyeing and finishing, and experimental condition.The goniophotometric curves for fabrics of same kind with different colors are same in general shape, and the reflectance or the height of the curves are changed to the extent of that they are in proportion with the brightness or the tristimulus value Y of the samples. The goniophotometric curve also varies in form when the incident angle is changed. Discussion and explanation for the above mentioned are given. Luster of the samples was calculated with methods suggested by different indexing systems.

Isolation and characterization of a lytic bacteriophage φKp-lyy15 of Klebsiella pneumoniae

Dear Editor,Bacteriophages(phages)are viruses that specifically infect and kill bacteria.They are ubiquitous throughout all environments that bacteria inhabit.Following their discovery by F.W.Twort in 1915 and F.d’Herele in 1917,bacteriophages were recognized as potential agents to treat bacterial diseases and phage therapy has been used

Probability-consistent spectrum and code spectrum

In the seismic safety evaluation (SSE) for key projects, the probability-consistent spectrum (PCS), usually obtained from probabilistic seismic hazard analysis (PSHA), is not consistent with the design response spectrum given by Code for Seismic Design of Buildings (GB50011-2001). Sometimes, there may be a remarkable difference be-tween them. If the PCS is lower than the corresponding code design response spectrum (CDS), the seismic fortifi-cation criterion for the key projects would be lower than that for the general industry and civil buildings. In the paper, the relation between PCS and CDS is discussed by using the ideal simple potential seismic source. The re-sults show that in the most areas influenced mainly by the potential sources of the epicentral earthquakes and the regional earthquakes, PCS is generally lower than CDS in the long periods. We point out that the long-period re-sponse spectra of the code should be further studied and combined with the probability method of seismic zoning as much as possible. Because of the uncertainties in SSE, it should be prudent to use the long-period response spectra given by SSE for key projects when they are lower than CDS.

空气动力学教学改革创新的探索与实践

空气动力学是一门应用面十分广泛的专业技术基础课,该课程有助于学生更好的学习专业后续课程以及今后从事相关专业工程技术工作。本文首先分析该课程的教学特点和现状,随后针对教学过程中存在的突出问题,以学为中心,以问题为导向,对理论和实验教学进行改革创新探索,培养学生的创新能力。

APPLICATION OF FRACTAL THEORY IN TRANSIENT CHAOTIC SIGNAL DETECTION

According to the definition of correlation dimension in fractal theory, this paper presented a method to determine and assess noise part in detected transient signal. Such work is essential to decrease the noise part in the detected signal. It is proved that heart period signal (HPS) is one typical sort of transient chaotic signal. Through experiment and simulation, the analysis of chaotic HPS in the detected signal was done. In the end, we deepen the researches on attractor dimension of HPS for persons who are different in age.

TOWARDS AN ONTOLOGY-BASED MULTI-AGENT MEDICAL INFORMATION SYSTEM BASED ON THE WEB

This paper described an ontology based multi agent knowledge process made (MAKM) which is one of multi agents systems (MAS) and uses semantic network to describe agents to help to locate relative agents distributed in the workgroup. In MAKM, an agent is the entity to implement the distributed task processing and to access the information or knowledge. Knowledge query manipulation language (KQML) is adapted to realize the communication among agents. So using the MAKM mode, different knowledge and information on the medical domain could be organized and utilized efficiently when a collaborative task is implemented on the web.

A STRESS VECTOR-BASED CONSTITUTIVE MODEL FOR COHESIONLESS SOIL (Ⅰ)-THEORY

On the basis of the sufficient consideration of vectorial characteristics of stress, a new nonlinear constitutive model for cohesionless soil under plane strain and 3-D conditions was presented in a way that the action effects of stress vector are decomposed into the action effect of mean effective stress and that of the stress ratio vector (ratio of deviatoric stress vector to mean effective stress). The constitutive model can take account of the influence of both numerical and directional changes of stress vector on deformation of soil simultaneously, and is applicable of both static and dynamic loading.

思想政治教育必须贯彻以人为本原则

思想政治教育贯彻以人为本原则,是马克思主义以人为本思想的重要体现,是实践“三个代表”重要思想、落实科学发展观的根本要求,是提高思想政治教育实效性的重要途径。在实践中贯彻以人为本原则必须遵循思想品德活动规律,坚持政治性和教育性相结合,思想政治教育与实现人的物质利益相结合,创造良好的育人环境,实施渗透式、激励式思想政治教育。

A NEW TECHNIQUE FOR COMPAIRING FUZZY NUMBERS USING AN INDEX OF OPTIMISM

Fuzzy numbers are convenient for representing imprecise numerical quantities in a vague environment, and their comparison or ranking is very important for application purposes. Despite many methods suggested in the literature, there is no single measure that is universally applicable to a wide variety of situations. This paper suggested a new method for comparing fuzzy numbers based on the combination of maximizing possibility and minimizing possibility using an index of optimism in [0,1] reflecting the decision makers’ risk taking attitude. The method is simple, but has many comparative advantages.

Preparation of Macroporous Poly (vinyl alcohol-co-triallyl isocyanurate) Beads Bearing Aminocarboxylic Acid as Functional Groups by Suspension Polymerization

Macroporous poly (vinyl acetate-co-triallyl isocyanurate) beads were prepared with suspension polymerization method. The copolymer beads were then transformed into poly (vinyl alcohol-co-triallyl isocyanurate) by ester exchange reaction. Aminocarboxylic acids were immobilized on the copolymer beads by the esterification of hydroxyl groups with diethyl-lenetriaminepentaacetic bisanhydride. The weak acid exchange capacities, specific surface areas and mean pore diameters of the resultant resin beads were measured.

Screening the stage-specific expression gene from different germ cells of rat

Objective: To screen the stage-specific expression genes from rat spermatogonia, pachytene spermatocytes and round spermatids. Methods: Highly purified spermatogonia were isolated from 9-day-old rats, pachytene spermatocytes and round spermatids from adult rats by sedimentation velocity at unit gravity, using 2%-4% BSA gradient in DMEM/F12 medium. A mRNA differential display method was used for screening the stage-specific expression gene. Results: Nineteen differentially expressed cDNA fragments were obtained. After excluding the false positive cDNA fragments by dot blot, 13 cDNAs were selected to clone and sequence. To obtain longer cDNAs, six ESTs were used to screen the rat testis λ-zap II cDNA library. Two longer cDNA fragments, designated as LY21 and LM66, were obtained. The analysis with DNAMAN software indicated that LY21 had a long open reading frame coding 372 amino acids while LM66 had no long open reading frame. LY21 were highly homologous with hnRNP H1. To observe the expression patterns of LY21 gene in the testicular cells, we performed in situ hybridization on testis sections from adult rats. The LY21 gene expression was found in the spermatogonia and primary spermatocytes.Conclusion: This study indicated that LY21 gene was associated with spermatogenesis. Further studies will be needed to explore the function of LY21.

THE FORMATION OF SHOCK WAVES OF THE EQUATIONS OF MAGNETOHYDRODYNAMICS

The property of fluid field of one-dimensional magnetohydrodynamics (MHD) transverse flow after the appearance of singularity is discussed. By the method of iteration, the strong discontinuity (shock wave) and entropy solution are constructed and the estimations on the singularity of the solution near the point of blow-up are obtained.

AFFINE TRANSFORMATION IN RANDOM ITERATED FUNCTION SYSTEMS

Random iterated function systems (IFSs) is discussed, which is one of the methods for fractal drawing. A certain figure can be reconstructed by a random IFS. One approach is presented to determine a new random IFS, that the figure reconstructed by the new random IFS is the image of the origin figure reconstructed by old IFS under a given affine transformation. Two particular examples are used to show this approach.