A Theoretical Test of the Geostrophic Momentum Approximation

A previously developed model of a 2-dimensional air flow with constant horizontal shear is used to estimeate the accuracy of the geostrophic momentum approximation by comparison of exact solutions when exist with approximate ones.     

Generation of Reactive Oxygen Species in Different Fractions of the Coelomocytes of Holothurian Eupentacta fraudatrix in Response to the Thermostable Toxin of Yersinia pseudotuberculosis in Vitro

Pure fraction (92% - 95%) of phagocytes (FP) and a mixture of amoebocytes (62%) and morula cells (38 % )-FPMC- of the holothurian Eupentacta fraudatrix ( Holothuroidea,Dendrochirota ) were obtained by using ficoll-verographine step gradient. Basal production of reactive oxygen species (ROS) in FP quantified by using reduction of nitroblue tetrazolium (NBT) was more than twice that in FPMC. Thermostable toxin of Yersinia pseudotuberculosis (TST) at differentconcentrations ( 0.2; 0.5; 2.5 μg/ml, but not 0.1 μg/ml) stimulated NBT reduction in FPMC after 24 h incubation. In FP, TST at concentrations of 0.1 and 0.2 μg/ml inhibited and at concentrations of 0.5 and 2.5 μg/ml stimulated NBT reduction after 24 h incubation. Maximal effect was observed in FP and FPMC at TST concentrations of 0.5 and 0.2 μg/ml, respectively. Addition of catalase (0.7 μg/ml) to the cells treated with TST (2.5 μg/ml) was followed by a decrease in NBT reduction compared to that under toxin treatment alone. TST stimulated superoxide dismutase activity in ccncentration-dependent manner (maximum at 0.5 μg/ml concentration in FP) after 24 htreatment, and this stimulation was prevented by a commercial catalase. Plant lectin concanavalin A stimulated NBT reduction more than 5-fold in FPMC compared to the control. With addition of TST, lectin stimulated ROS to lesser extent than that with lectin alone. When catalase, TST, and lectin were added into the FPMC simultaneously, ROS increase was similar to that under lectin treatment alone. On the whole, data obtained indicated that ROS generation in holothurian coelomocytes especially occurs in both stimulated and not stimulated phagocytes, and that changes in ROS production by these cells may be one of the mechanisms of antibacterial protection of holothurians.     

FORGING ASIA′S GLOBAL TRANSPARK IN THE PEARL RIVER DELTA AT ZHUHAI

1 NEEDFORNEWCOMPETITIVENESSINTHEPEARLRIVERDELTAIn1978ChinaadoptedanewapproachofOpen andReforminitsdevelopment.Priortothis,HongKongwasaBritish-runenclaveoffreetrade,andwaslittlerelatedeconomicallywithitsnextdoorneighborandnaturalhinterland—thePearl(Zhujiang)RiverDelta(PRD)(SIT,1991).Sincethen,localinitiativesofGuangdongProvinceanditsconstituentmunicipalitieshaveprovidedanattractivemilieuforHongKongin-vestment.IthassoongrownintoHongKong'snewmanufacturingbasewhileHong…     

MIXTURE ANALYSIS USING FACTOR ANALYSIS.Ⅱ:SELF-MODELING CURVE RESOLUTION

One of the major applications of factor analysis in the chemical literature,self-modeling curve resolution(SMCR),is covered in this review,including a historical account of the inethods derived from Lawtonand Sylvestre's original method.Papers treating the theory or applications of SMCR are included.Qualitative and quantitative applications are described where appropriate.     

Convective Boundary Layer in the Region of the Monsoon Trough-A Case Study

A case study of the convectively driven monsoon boundary layer has been carried out using the aerological observations at four stations in the region of monsoon trough during Monsoon Trough Boundary Layer Experiment (MONTBLEX) 1988. The Convective Boundary Layer (CBL) in the region of monsoon trough did not show double mixing line structure. A single mixing line representing the CBL with different stabilities with respect to the convective activities was observed.     

《中国天文地质事件》评述

该书的作者们独辟蹊径地研究整个显生宙地层剖面,其目的是从这些剖面可能揭示出一系列地外成因的事件。暂且不论这费劲的工作收益有多大,一个引人深思的问题在于,象这样一本书在10年前能否被接受并出版?但正是在这10年间,许多地质学家已注意到:他们研究的课题同天文学和天体物理学有联系。1980年出现了观念性的变化,在这之前,任何一种把     

印度马德拉斯含水层系统水文地球化学对人类健康的影响

从1985年开始,安娜大学水资源中心在马德拉斯含水层系统(MAS)有规律地进行了水文地球化学研究,该含水层系统包括北-西北部多层含水层和南部半承压含水层。马德拉斯大城市居民的60～70~*％,供水来自马德拉斯含水层系统,在干旱年份,近     

地质演化与生物演化体系(岩石学中的变成学派)

自古以来,metamorphism(变质作用,变异)就是一种用来描述形态变化,即转变的概念.这一术语具有特殊的含意,并且在不同的自然学科中有着不同的用法.在生物学中,“metamorphism”描述生长的变异,而在地质学中,则用它来表述在温度和压力相对增加的条件下,或者在地球营力的作用下,岩石的变形、重结晶和变晶生长.     

Methods Used to Study Bacterial Diversity in the Marine Environment around Qingdao

Pollution has a considerable effect on biological communities, in terms of size and diversity of the populations. Yet, the precise consequences of human activity on microbial communities in the marine environment are poorly understood. Therefore, in an ongoing collaborative research programme between Heriot-Watt University and the Ocean University of Qingdao, bacteria were isolated in 1999 and 2000 from marine sediment, seawater, seaweed, fish and shellfish, taken from locations in Shandong Province adjacent to Qingdao. Sampling locations were comprised of industrial and aquacultural sites and a clean, control site. In order to analyse microbial diversity, a polyphasic approach was adopted for characterisation of these isolates, specifically through examination of key phenotypic traits, i.e. using Biolog GN MicroPlateTM profiles, bacterial whole cell protein profiles and 16S and 23S rRNA gene sequences. These techniques yielded complex taxonomic data, which were subjected to statistical and cluster analyses. The application of these methods to studies of microbial communities is discussed.