Induction of animal model of Graves' disease in BALB/c mice

Objective To construct an animal model of Graves' disease (GD) by immunizing BALB/c mice with hM12 cells co-expressing major histocompatibility complex (MHC) class Ⅱ molecules and human thyrotropin receptor (TSHR) molecules. Methods BALB/c mice in experimental group (H-2d) were immunized with hM12 cells Intraper-itoncally every 2 weeks for six times, while mice in control group were immunized with M12 cells. Five weeks later, the thyroids were histologically examined, and serum samples were tested for thyroid-stimulating antibodies (TSAb) and thyroid hormone levels. Results One BALB/c mouse in experimental group developed Graves'-like disease. Total T4 and T3 levels in this mouse were above the upper limit of normal, TSAb activity was displayed in its serum. The thyroid histologically showed the features of thyroid hyperactivity including thyrocyte hypercellularity and colloid absorption.None of control mice developed Graves'-like disease. Conclusion An animal model with some characteristics of human Graves' disease was successfully induced and the model will facilitate studies aimed directly at understanding the patho-genesis of autoimmunity in Graves' disease.     

Glutamate enhances the expression of vascular endothelial growth factor in cultured SD rat astrocytes

Objective To study the effect of glutamate on the expression of vascular endothelial growth factor (VEGF) mRNA and protein in cultured rat astrocytes. Methods Cultured rat astrocytes were randomly divided into 6 groups: control group (C), glutamate group (G), QA group (Q), DCG-IV group (D), L-AP4 group (L) and glutanmte-FMCPG gronp (G+M). Cells were cultured under nomoxic condition (95% air, 5% CO2). RT-PCR and ELISA methods were used to detect the expression of VEGF mRNA and protein in cultured astrocytes, respectively. G+ M group was preincubated with lmM MCPG for 30 min prior to the stimulation with glutamate. There were 7 time points at 0,4,8,12,16,24 and 48 h in each group except G+M group. Results The expression of VEGF mRNA and protein did not differ significantly among D group, L group and C group. Different from that in C group, the expression of VEGF mRNA and protein could be enhanced both in a dose-dependent and time-dependent manner in G group and Q group. Meanwhile, the enhanced expression of VEGF mRNA and protein in G group was completely suppressed by MCPG after 24 h. Conclusion Glutamate can increase the expression of VEGF mRNA and protein in cultured astrocytes, which may be due to the activation of group I metabotropic glutamate receptors in astrocytes.     

基于3-RPS空间并联机构的发动机支撑台架设计

基于3-RPS空间并联机构原理,分析了该并联机构应用于发动机支撑台架设计中存在的问题,并对3-RPS机构进行改良优化,设计了某发动机支撑台架.实际应用表明,所设计的发动机支撑台架能很好地满足发动机的工作要求.     

驾车应避免发动机超速运行

介绍发动机超速的故障现象,分析了其故障原因,提出了解决发动机超速的方案,并对驾驶员存在的错误认识作出提醒。     

软粘土扰动状态流变模型研究现状与发展

从软土工程实际出发,指出在软土应力应变本构模型的构建中,应考虑扰动状态概念以及流变特性等影响因素的必要性。进而,对软粘土扰动状态概念本构模型研究、流变本构模型研究等成果应用现状及其存在问题进行阐述。最后,对真实描述软土工程应力应变性状的本构模型构建的发展趋势提出了见解。     

基于多智能体博弈的路径选择策略仿真研究

系统最优与用户最优代表了交通分配中路网管理者与出行者两种不同的利益出发点。在综合考虑两者在路径选择过程中动态交互特点的基础上,引入博弈论的思想协调两者的利益冲突,建立了路网系统管理者与出行者之间的路径选择博弈模型。为验证模型的有效性,结合多智能体技术进行了相应的仿真实验,并利用多智能体仿真软件Starlogo进行模拟。通过对无信息无博弈（随机）出行、用户最优出行、有信息有博弈出行以及系统最优出行等4种不同仿真方案的比较分析,验证了系统与出行个体之间协调的博弈模型性能满足了驾驶员出行需求,提高了路网整体效率,为建立实用的诱导策略提供了参考。     

Walsh threshold matched-filtering based anti-collision for surface acoustic wave tags

Surface acoustic wave (SAW) tags are truly passive devices and do not contain any intelligence, so the question of multiple read in the reading range comes up. The paper suggests a Walsh matched-filtering method in Walsh field to distinguish the collision tags with a threshold. In advance, the code states with special sequency are selected from large possible states and the sequency variables of these tags are saved in a database. When a few tags are read simultaneously in read range, the received signal is filtered by the known sequency of single tag in database, and then these tags can be distinguished by the filtered result. Proper threshold selection improves operation speed. Experiment proves that this method is useful and reliable.     

Support vector machine-based fuzzy rules acquisition system

This paper proposes a support vector machine-based fuzzy rules acquisition system (SVM-FRAS). The character of SVM in extracting support vector provides a mechanism to extract fuzzy If-Then rules from the training data set. We construct the fuzzy inference system using fuzzy basis function (FBF). The gradient technique is used to tune the fuzzy rules and the inference system. Theoretical analysis and comparative tests are performed comparing with other fuzzy systems. Experimental results show the SVM-FRAS model possesses good generalization capability as well as high comprehensibility.     

粉煤灰、水泥、碎石基层施工过程质量控制

根据对营口市2008年市区街巷道路改造工程(一标段)施工实例分析和研究,阐述粉煤灰、水泥、碎石基层施工过程质量控制要点.     

AF-16I型改性沥青混凝土路面施工质量控制

以大连至庄河高速公路路面工程AF-16 I型改性沥青混凝土路面施工为例,详细说明路面施工中的质量控制重点,保证了路面平整度,提高了路面施工质量。