艾叶粗提物的分离提取及其抗肝癌活性组分筛选

为筛选艾叶水提物的抗肝癌活性组分,采用去溶剂和乙醇沉淀法,从等量的艾叶水提液中获得总水提物以及去多糖提取物和多糖提取物2种粗提物,用等量的去离子水溶解各提取物制成溶液,分别以不同的浓度作用HepG2细胞,倒置显微镜观察细胞的生长状态,MTT法测定细胞活力。结果为:处理肝癌细胞24~48h,不同浓度的总水提物和去多糖水提物能使肝癌细胞明显皱缩,OD值较对照组明显减小(P0.01),细胞最终死亡;而低、中浓度的多糖提取物对肝癌细胞的形态无明显影响,OD值较对照组小,但无统计学差异,高浓度的多糖提取物能使肝癌细胞明显皱缩,OD值较对照组小,有差异(P0.05)。去多糖水提物和总水提物的活性较强,能使肝癌细胞明显皱缩,阻滞其增殖,最终诱导死亡,多糖提取物作用较弱,能抑制肝癌细胞增殖。因此,进一步筛选抗癌活性精细组分或先导化合物可从艾叶去多糖水提物中深入研究。     

基于作业成本法的物流作业分析与改善

作业成本法以＂作业＂为单位计算物流服务的成本,为物流企业成本核算提供了较为科学的体系和方法,同时引入了作业分析与优化的理念,其应用环境与物流企业独特的生产运作方式不谋而合。物流企业可以通过消除和减低无效作业,选择和分享有效作业来改善物流作业,以降低物流作业成本。     

FDI溢出效应、创新活动与技术进步—基于中国高技术产业的实证分析

科技创新投入、人力资源积累以及FDI引致的技术外溢效应都对中国高科技产业技术进步产生正向的影响。当区分行业中不同的产权组织形式后再进行检验时,结果差异很大,国有企业的技术进步主要来源于人力资本积累而非科技创新投入,FDI技术外溢效应对技术进步也产生不利影响;而三资企业中的技术进步基本上来源于FDI技术外溢效应,而不是来源于科技创新投入和人力资源的积累。     

The Dynamics of Security Trades,Quote Revisions,and Market Depths for Actively Traded Stocks

We examine the dynamics of return volatility, trading volume, and depth—in an intraday setting for a sample of actively traded NYSE and NASDAQ stocks. We show that depth is a useful intervening variable and mitigates the impact of trading activity on price volatility. Furthermore, depth is affected by the perception of prevailing information asymmetry between informed and uninformed traders. We demonstrate empirically that the NYSE supplies greater depth under conditions of high, perceived information asymmetry as compared to NASDAQ. NASDAQ makes up for this deficiency by its capability of managing large volume shocks without a major decline in depth.JEL Classification: C32, D82, G10     

Individual and Environmental Determinants of Entrepreneurship

I argue that to better understand the emergence of entrepreneurial activity in a given country, we need to complement the analysis of the psychological and non-psychological characteristics of the individual entrepreneur that currently dominates entrepreneurship studies with the analysis of environmental characteristics in terms of the availability of resources and competition, as well as the conditions of the institutions that govern economic activity. These three groups of factors enable the entrepreneur not only to identify a business opportunity, but also to exploit it, and create a firm that achieves profitability and generates wealth.     

从生产力的发展看我国的编辑活动

我国编辑活动的历史源远流长。本文通过对我国不同时期生产力状况的考察，论述了不同时期的生产力状况下的编辑活动。揭示了编辑活动与生产力发展的内在联系：生产力的发展制约着编辑活动，编辑活动随着生产力的发展由低级向中、高级不断地变革、进化、发展。     

The Sustainable Growth Rate of Non–profit Organisations: The Effect of Efficiency, Profitability and Capital Structure

The activity growth of non–profit organisations is financially contrained by their efficiency, profitability and capital structure. In this paper, a very general expression relating these four organisational parameters is derived and its practical use is discussed.     

How far can changes in general business activity be forecasted?

An F test [Nelson (1976)] of Parzen's prediction variance horizon [Parzen (1982)] of an ARMA model yields the number of steps ahead that forecasts contain information (short memory). A special 10 year pattern in Finnish GDP is introduced as a ‘seasonal’ in an ARMA-model. Forecasts three years ahead are statistically informative but exploiting the complete 10 year pattern raises doubts both about model memory and model validity.     

基于价值链理论的商业银行业务流程优化研究

商业银行业务活动和流程是否协调，是决定其客户价值的重要基础。本文以价值链理论为指导，对我国商业银行的业务活动与业务流程进行归类分析，阐述业务活动与流程之间互相联系、共同影响客户价值的关系，建立了商业银行业务流程的优化模型。业务活动的优化关键是解决商业银行的活动瓶颈、不断对商业银行的弱势增值活动进行优化；业务流程的优化可以通过外包非核心业务、集中资源发展商业银行核心业务来解决。商业银行在业务流程优化过程中要注意以客户价值的提高为核心、差别化设计服务流程、集中资源发展核心业务等战略环节。     

基于物联网技术的港口煤炭作业流程的系统分析与设计

以秦皇岛港煤炭作业流程为研究对象,分析煤炭在港内流转各环节存在的问题及改进需求,从物联网技术应用角度,提出了煤炭作业流程的系统框架,设计了满足各环节需求的四大主要功能模块,即智能闸口管理、煤炭推场管理、港口装卸智能化管理及作业机械监控管理模块的功能与作用.