Intracellular NAD(H) levels control motility and invasion of glioma cells

Oncogenic transformation involves reprogramming of cell metabolism, whereby steady-state levels of intracellular NAD⁺ and NADH can undergo dramatic changes while ATP concentration is generally well maintained. Altered expression of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme of NAD⁺-salvage, accompanies the changes in NAD(H) during tumorigenesis. Here, we show by genetic and pharmacological inhibition of NAMPT in glioma cells that fluctuation in intracellular [NAD(H)] differentially affects cell growth and morphodynamics, with motility/invasion capacity showing the highest sensitivity to [NAD(H)] decrease. Extracellular supplementation of NAD⁺ or re-expression of NAMPT abolished the effects. The effects of NAD(H) decrease on cell motility appeared parallel coupled with diminished pyruvate-lactate conversion by lactate dehydrogenase (LDH) and with changes in intracellular and extracellular pH. The addition of lactic acid rescued and knockdown of LDH-A replicated the effects of [NAD(H)] on motility. Combined, our observations demonstrate that [NAD(H)] is an important metabolic component of cancer cell motility. Nutrient or drug-mediated modulation of NAD(H) levels may therefore represent a new option for blocking the invasive behavior of tumors.     

建立可行的最高标准,促进海事安全发展(英文)

提高海事安全的有效方法是建立海事安全标准.从技术性、可操作性以及国际性3个方面分析建立可行的最高标准的方法,使安全标准能够广泛有效地实施,进而有效地促进海事安全的发展.     

构建网络安全环境 抵御“黑客”侵袭风险——追踪“基于Web的实时网站防篡改系统”实施情况

项目概况 随着计算机和通信技术的迅速发展,网络成为当今社会发展的一个主题,网络的开放性、互联性、共享性程度的扩大,也使得黑客针对网站的攻击和篡改事件时有发生.因此,严格地说,所有的Web网站都需要进行文件系统保护,防止非授权人员随意篡改内容.对于更新快、容量大、受众多、权威性强的政府电子政务网站尤显重要.     

蜂窝纸板与瓦楞纸板的复合刚度试验及分析

通过试验测试了蜂窝纸板和瓦楞纸板及其复合板的刚度 ,并在理论上作了分析 .结果表明 ,面纸的纵横方向对纸板的弯曲刚度起决定性作用 ,复合板的刚度性能较单层板大大增强 .     

A Property of the CHAID Partitioning Method for Dichotomous Randomized Response Data and Categorical Predictors

In this paper, we present empirical and theoretical results on classification trees for randomized response data. We considered a dichotomous sensitive response variable with the true status intentionally misclassified by the respondents using rules prescribed by a randomized response method. We assumed that classification trees are grown using the Pearson chi-square test as a splitting criterion, and that the randomized response data are analyzed using classification trees as if they were not perturbed. We proved that classification trees analyzing observed randomized response data and estimated true data have a one-to-one correspondence in terms of ranking the splitting variables. This is illustrated using two real data sets.     

Design for availability: A holistic approach to create value for manufacturers and customers of capital goods

This research introduces a holistic framework called Design for Availability that uses the principles of Lean Sigma and Design for X to cost-effectively optimize the availability of capital goods(i.e., technical systems used in the production of end-products or -services such as medical systems, airplanes,and manufacturing equipment) throughout their entire lifetime.Manufacturers require such a framework because users of capital goods increasingly insist on high system availability levels against reduced lifetime costs.The Design for Availability framework allows manufacturers to determine the current status of system availability and associated lifetime costs,and to identify opportunities to create additional value for themselves and their customers.A case study at a global manufacturer of capital goods in the food processing industry illustrates how the framework can be used in practice and to what extent the manufacturer and customers may profit from applying Design for Availability.     

大肠杆菌葡萄糖脱氢酶基因的克隆与原核表达

克隆出大肠杆菌编码葡萄糖脱氢酶(PQQGDH)的 gcd 基因，构建了诱导型表达载体pET28a-gcd，转化大肠杆菌E. coli BL21后获得阳性克隆菌株BL21/pET28a-gcd。IPTG诱导后，经SDS-PAGE分析表明，该工程菌PQQGDH的表达量约为对照菌的18倍，约为18.2 mg/L，实现了高表达。此外，研究发现添加MgCl₂能提高PQQGDH的表达量。     

1997-2011年经济类英语新词认知语义阐释

新词是词汇学研究的重要方面。新词的产生是一个认知的过程。伴随经济贸易的迅猛发展,经济类英语新词大量出现。本文对1997-2011年间的经济类英语新词作了定量考察和定性分析,详细探讨了经济类英语新词的构建方式,并从认知语义学的视角解释了该类新词的语义建构,来揭示人类创造新词的思维方式、心理机制和认知特点,为理解新词的产生和研究经济现象提供了新的视角。     

浅析高校图书馆自助借还书服务——以湖北民族学院图书馆为例

自助借还书系统进入高校图书馆是大势所趋,正发挥着越来越大的作用,如何利用好自助借还系统是图书馆面临的现实问题。结合湖北民族学院图书馆的实际情况,对自助借还书系统使用过程中可能出现的问题进行了分析和探讨,并提出了相应的解决对策。     

双轴跟踪光伏阵列的日地天文理论仿真实现

固定倾角的传统安装方式导致光伏阵列输出效率较低。根据日地天文理论,仿真太阳和地球间的运动,分析一小时、一天、一个月以及一年等不同时间范围内的太阳高度角和方位角的变化规律,仿真结果表明在不同时刻,日地间的高度角、时角、方位角等都处于变化当中,即传统的固定倾角的安装方式不能有效跟踪太阳运动,如将日地天文理论应用于光伏阵列的双轴跟踪,可以有效地提高光伏阵列的输出效率。