甘草纤素对实验动物化学性肝损伤保护功能研究

目的:了解甘草纤素对大鼠化学性肝损伤的保护作用。方法:按照卫生部《保健食品功能学评价程序和检验方法》进行。并比较四氯化碳染毒后第48h和第5d处死动物对各项指标的影响。结果:与肝损伤模型对照组比较,染毒后第48h,甘草纤素的二个剂量组血清ALT(丙氨酸氨基转移酶)水平均有显著降低(p<0.05),中、高剂量组血清AST(天门冬氨酸氨基转移酶)水平也有显著降低(p<0.05)。受试物的高剂量组可改善肝细胞的退行性变,且高剂量组可明显减轻CCl4引起的肝细胞坏死(p<0.05)。结论:适量甘草纤素对CCl4所致动物急性肝损伤具有保护作用。     

关于正整数的k次根的整部

对于给定的自然数m，令口α（m)为m的是的次根的整部。即：α(m)=[m^1/k]。研究了α(m)的渐近性质，并给出了一个有趣的渐近公式。     

On the Locus of Speed-Accuracy Trade-Off in Reaction Time: Inferences From the Lateralized Readiness Potential.

Lateralized readiness potentials (LRPs) were used to determine the stage(s) of reaction time (RT) responsible for speed-accuracy trade-offs (SATs). Speeded decisions based on several types of information were examined in 3 experiments, involving, respectively, a line discrimination task, lexical decisions, and an Erikson flanker task. Three levels of SAT were obtained in each experiment by adjusting response deadlines with an adaptive tracking algorithm. Speed stress affected the duration of RT stages both before and after the start of the LRP in all experiments. The latter effect cannot be explained by guessing strategies, by variations in response force, or as an indirect consequence of the pre-LRP effect. Contrary to most models, it suggests that SAT can occur at a late postdecisional stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

动态矩阵控制系统稳定域的根轨迹分析

本文使用根轨迹技术从理论上分析了纯滞后工业过程参数变化对系统稳定性的影响,得到了一个与设计参数有关的稳定域,从而为设计参数自动整定提供了参考。     

方程根数对反应系数法求解负荷的影响

房间围护结构热力系统传递矩阵元素Ｂ（Ｓ）的根数多少或根值大小，直接影响反应系数的精度。其值取多少，国内外没有统一标准。本文结合空调房间的下部送风，针对不同结构的房间进行探讨，发现最小根值取到（—３０）时，即足能满足一般精度要求。     

Annexin 1 Is a Component of eATP-Induced Cytosolic Calcium Elevation in Arabidopsis thaliana Roots

Extracellular ATP (eATP) has long been established in animals as an important signalling molecule but this is less understood in plants. The identification of Arabidopsis thaliana DORN1 (Does Not Respond to Nucleotides) as the first plant eATP receptor has shown that it is fundamental to the elevation of cytosolic free Ca²⁺ ([Ca²⁺]_cyt) as a possible second messenger. eATP causes other downstream responses such as increase in reactive oxygen species (ROS) and nitric oxide, plus changes in gene expression. The plasma membrane Ca²⁺ influx channels involved in eATP-induced [Ca²⁺]_cyt increase remain unknown at the genetic level. Arabidopsis thaliana Annexin 1 has been found to mediate ROS-activated Ca²⁺ influx in root epidermis, consistent with its operating as a transport pathway. In this study, the loss of function Annexin 1 mutant was found to have impaired [Ca²⁺]_cyt elevation in roots in response to eATP or eADP. Additionally, this annexin was implicated in modulating eATP-induced intracellular ROS accumulation in roots as well as expression of eATP-responsive genes.     

反对称矩阵的外在美和内在美的教学呈示

关于对称矩阵的美韵,笔者已经撰文做过研究,而反对称矩阵的美韵并不亚于对称矩阵。本文对反对称矩阵之美亦从“内”与“外”进行分析和探索。     

重塑黄土与植物根系界面摩擦离散元分析

油松作为一种植根于黄土地区的常见植物,在提高黄土强度方面起重要作用。为了弄清油松根系在黄土地区的固土效应,本文采用离散单元法(Distinct Element Method)模拟根系拉拔试验,分析了法向压力、根系埋深、含水率对根-黄土界面摩擦力学特性的影响。结果表明:拉拔试验中,根-黄土界面峰值强度、残余强度随着法向力的增大而增大;峰值强度、残余强度随着根系埋深的增加而增大;随着含水率的降低,根-黄土界面峰值强度、残余强度呈增大的趋势。     

Effects of individuals' locus of control and computer self-efficacy on their e-learning acceptance in high-tech companies

High-tech companies encounter intense competition in today's global economy. With rapid changes in working environments, high-tech employees must learn quickly and effectively to solve difficult problems and increase their productivity. Many large high-tech companies have recently implemented electronic learning (e-learning) for employee training. However, e-learning systems are expensive and often underutilised. Therefore, understanding the factors associated with acceptance to e-learning are of priority concern. By integrating locus of control, computer self-efficacy and technology acceptance model (TAM) into one model, this study examines the feasibility of the extended TAM to explain employee acceptance of e-learning systems. Data were collected from 223 employees at five high-tech companies located in the Hsinchu Science Park, Taiwan. Analytical results indicate that locus of control had significant direct effects on perceived usefulness and perceived ease of use. Computer self-efficacy had significant direct effects on perceived ease of use and behavioural intention to use. Overall, analytical results provide strong support for using the extended TAM to explain user acceptance of e-learning systems. The research and practical implications of findings are discussed.