Caspase-3在D-半乳糖致衰老SD大鼠海马的表达

目的了解Caspase-3在D-半乳糖致衰老SD大鼠脑海马的表达情况.方法将健康成年雄性SD大鼠40只随机分为两组,分别为对照组和衰老组,每组各20只.以Morris水迷宫实验评估动物的学习记忆功能,应用免疫组织化学染色法检测Caspase-3在两组大鼠脑海马中的表达水平.结果衰老组大鼠的逃避潜伏期较对照组明显延长,在第Ⅲ象限逗留的时间和跨越平台次数较对照组明显减少.Caspase-3的免疫阳性反应物的表达在衰老组较对照组明显增多.结论D-半乳糖可通过活化Caspase-3,促进海马神经元的凋亡,引发大鼠学习记忆功能减退.

INCLINED LAMINAL COMBINATION MODEL OF 3D BRAIDED COMPOSITES

As an advanced composite material, the 3D braided composite has received more and more attention in foreign countries. However, it has received less attention in China. The geometric unit cell which can describe the basic structure and the relationship between the braiding angle and geometric parameters of the fabric and fiber volume ratio are given in this paper based on two 3D braiding processes, namely, the four-step and the twostep ones. Several existing mechanical models to predict groperties of the 3D braided comPOsites are discussed and their shortcomings are pointed out herein. Then a new model called the inclined laminal combination model is proposed, which is based on the classical laminated plate theory and can predict the basic mechanical behavior of the two 3D braided composites with four-step or two-step braid. In the model, each yarn in the unit cell is regarded as an inclined laminate and then a 3D analysis is performed. It is found that the predicted mechanical properties of the 3D braided composites by the proposed model are compared well with the experimental data.

基于D3SD和TOT的填充水箱应用实现

基于D3SD和TOT功能块,在实验室环境下用罗克韦尔软件设计并实现填充水箱过程。在罗克韦尔软件平台上,采用RLIM模拟对象,通过TOT测量填充水箱流量,配置D3SD的开启、细流、关闭三种状态,根据TOT累积的填充水箱流量信号,决定D3SD采取哪种状态控制电磁阀。实验结果表明达到填充水箱的有效控制,使学生对过程控制有深入的了解,为将来使用在实际当中打下基础。

大洋D^3-CG SD字幕机在合肥电视台节目制作中的应用

电视字幕是电视节目构成要素中不可或缺的重要组成部分,而字幕机有着方便、快捷、灵活性好等优点,成为电视台节目制作的必用设备。本文将介绍大洋D3-CGSD字幕机的特点以及功能,并以大洋D3-CGSD字幕机在合肥电视台节目制作的应用为例,总结字幕制作的经验。

Tensile Properties of 3-Dimension-4-directional Braided C_f/Si C Composite based on Double-scale Model

The longitude tensile properties of 3-Dimension-4-directional（3D-4d） braided C/Si C composites（CMCs） were investigated with the help of a double scale model. This model involves micro-scale and unit-cell scale. In micro-scale, the tensile properties of fiber tows which involves matrix cracking, interfacial debonding, and fiber failure are studied. The unit-cell scale model can reflect the braided structure and simulate the tensile properties of 3D-4d CMCs by introducing the tensile properties of fiber tows into it. Quasi-static tensile tests of 3D-4d braided CMCs were performed on a PWS-100 test system. The predicted tensile stressstrain curve by the double scale model is in good agreement with that of the experimental results.

Determination of Trace Amounts of Zinc, Iron and Copper by Flame Atomic Absorption after Their Preconcentration Using Sodium Dodecyl Sulfate (SDS) Coated Alumina Nanoparticles Modified with 3-Mercapto-D-Valin from Environmental Samples

A sensitive and simple solid phase extraction method for the simultaneous determination of trace and toxic metals in environmental samples has been reported. The method is based on the adsorption of Zinc, Iron and Copper on SDS-coated alumina nanoparticles, which is also modified with 3-mercapto-D-valine. The retained analyte ions on modified solid phase were eluted using 5 mL of 4 mol·L﹣1 HNO3. The analyte determination was carried out by flame atomic absorption spectrometry. The influences of some metal ion and anions on the recoveries of understudy analyte ion were investigated. The influences of the analytical parameters including pH, ligand and SDS amount, eluting solution (type and concentrations) and sample volume on metal ions recoveries were investigated. The extraction efficiency was > 98% with relative standard deviation lower than 3% the method has been successfully applied for the extraction and determination of these ions content in some real samples. Prepared adsorbent was characterized by SEM and FT-IR measurements.

Effective Thermal Conductivity for 3D Five-Directional Braided Composites Based on Microstructural Analysis

A method for predicting effective thermal conductivities(ETCs) of three-dimensional five-directional(3D5D) braided composites is presented. The effective thermal conductivity prediction method contains a digital image processing technology. Multiple scanning electron microscopy(SEM)images of composites are analyzed to obtain actual microstructural features. These actual microstructural features of 3D5D braided composites are introduced into representative volume element(RVE) modeling. Apart from applying actual microstructural features,compression effects between yarns are considered in the modeling of RVE,making the RVE more realistic. Therefore,the ETC prediction method establishes a representative unit cell model that better reflects the true microstructural characteristics of the 3D5D braided composites. The ETCs are predicted with the finite element method. Then thermal conductivity measurements are carried out for a 3D5D braided composite sample.By comparing the predicted ETC with the measured thermal conductivity, the whole process of the ETC prediction method is proved to be effective and accurate,where a relative error of only 2.9 % is obtained.Furthermore,the effects of microstructural features are investigated,indicating that increasing interior braiding angles and fiber fill factor can lead to higher transverse ETCs. Longitudinal ETCs decrease with increasing interior braiding angles,but increase with increasing fiber fill factor. Finally,the influence of variations of microstructure parameters observed in digital image processing are investigated. To explore the influence of variations in microstructural features on variations in predicted ETCs,the actual probability distributions of microstructural features obtained from the 3D5D braided composite sample are introduced into the ETC investigation. The results show that,compared with the interior braiding angle,variations in the fiber fill factor exhibit more significant effects on variations in ETCs.

Electrical⁃Mechanical Coupling Behaviors and Thermal⁃Resistance Effects of 3D Braided Composites

Electrical-mechanical coupling behaviors and thermal-resistance effects of 3D braided composites under external loads are important for structural health monitoring(SHM). Electrical conductivity and electrical-mechanical coupling behaviors of 3D braided carbon fiber/epoxy composites under uniaxial tension were reported. It was found that the transverse resistance decreased and the axial resistance increased with the increasing braiding angle. The fractional change in resistance increased linearly as the strain was below 1.0%, and the nonlinearity appeared when the strain exceeded 1.0%. The negative temperature coefficient(NTC) effect was observed before the glass transition temperature Tg of epoxy resin, while there was a positive temperature coefficient(PTC) effect after Tg.

Yarn Architecture Analysis of Two-step 3D Braided Composites

A comprehensive study of yarn architecture of two-step rectangle 3D braided composites is presented. Firstly, the braided surface, the shapes of yarns and the intertwining between braider yams and axial yams are analyzed from experimentation. With the microstructure being defined, three levels of unit cell structure are identified, i.e. large unit cell, second unit cell and minimal unit cell. Secondly, based on the minimal unit cell in the interior and on the boundary of the entire cross-section, the deformations of axial yams squashed by braider yams contribute to the increase of the fiber packing factors of axial yams. Finally, the predicted fiber volume fraction of the composites decreases with the increase of linear density of the braider yam and the pitch length. Favorable correlations between the predicted and the experimental results arc found for six groups of the composites.

Effects of Microstructure on Quasi⁃Static Transverse Loading Behavior of 3D Circular Braided Composite Tubes

The effects of microstructure on quasi-static transverse loading behavior of 3D circular braided composite tubes were studied. Transverse loading tests were conducted. Transverse load-deflection curves were obtained to analyze the effects of braiding parameters including the braiding angle, the wall thickness, and the diameter on the transverse loading of 3D circular braided composite tubes. Breaking loads, moduli and strengths had also been used to describe the transverse loading behaviors. The failure morphologies were shown to reveal damage mechanisms. From the results, the increase in braiding angle, wall thickness and diameter increases the ability of anti-deformation and breaking load of braided tubes. The breaking load of specimen with a braiding angle of 45° is about 1.68 times that of specimen with a braiding angle of 15°. The breaking load of specimen with 4 layers of yarns is about 2.15 times that of specimen with 2 layers of yarns. The breaking load of the tube with a diameter of 25.5 mm is about 2.39 times that of the tube with a diameter of 20.5 mm.

Defects Recognition of 3D Braided Composite Based on Dual-Tree Complex Wavelet Packet Transform

Textile-reinforced composites,due to their excellent highstrength-to-low-mass ratio, provide promising alternatives to conventional structural materials in many high-tech sectors. 3D braided composites are a kind of advanced composites reinforced with 3D braided fabrics; the complex nature of 3D braided composites makes the evaluation of the quality of the product very difficult. In this investigation,a defect recognition platform for 3D braided composites evaluation was constructed based on dual-tree complex wavelet packet transform( DT-CWPT) and backpropagation( BP) neural networks. The defects in 3D braided composite materials were probed and detected by an ultrasonic sensing system. DT-CWPT method was used to analyze the ultrasonic scanning pulse signals,and the feature vectors of these signals were extracted into the BP neural networks as samples. The type of defects was identified and recognized with the characteristic ultrasonic wave spectra. The position of defects for the test samples can be determined at the same time. This method would have great potential to evaluate the quality of 3D braided composites.

Statistical Model of the 3-D Braided Composites Strength

Based on the statistical model for the tensile statistical strength of unidirectional composite materials and the stress analysis of 3-D braided composites, a new method is proposed to calculate the tensile statistical strength of the 3-D braided compos- ites. With this method, the strength of 3-D braided composites can be calculated with very large accuracy, and the statistical parameters of 3-D braided composites can be determined. The numerical result shows that the tensile statistical strength of 3-D braided composites can be predicted using this method.

3D Braided Material Based on Space Group <i>R</i>3 Symmetry

A unit cell geometrical structure was found with the use of symmetry operations corresponding to the point group C3. Based on the symmetry of space group R3, a 3D braided geometrical structure was obtained by transforming the unit-cell. The features corresponding to this braided structure were studied. The fiber volume percentage and variational tendencies of the material were predicted by establishing a geometric model.

3D原音,让音乐飞 山水汉兰达专用机SDRS技术评测

从音响开始。到DVD、导航、车载信息服务。一度车载主机陷入为功能论的境地。导致很多厂家把很多精力都投入到这方面，忽视了用户最基本的需求，而今才有部分厂家意识到了这个问题？回归到本源，回到消费者最初始也是最重要的需求，这才是真正做产品的精神。

3D NAND加持影驰ONE 120GB SSD

不久前，影驰举办了一场别开生面的线上发布会，并为消费者们推出了一个全新的SSD产品系列——ONE。这个SSD系列以“oNE里挑一”为口号，定位于年轻消费群体。

1,25-(OH)_2D_3对肺纤维化大鼠肺泡Ⅱ型上皮细胞中Ca^(2+)浓度和PI3K/AKT/mTOR通路的影响

目的特发性肺纤维化(idiopathic pulmonary fibrosis,IPF)是一种慢性炎症性疾病,病因不明,缺乏有效的治疗方法。文中旨在探讨肺泡Ⅱ型上皮细胞中Ca^(2+)和PI3K/AKT/mTOR通路在大鼠IPF中的作用,以及1,25-(OH)_2D_3对Ca^(2+)浓度和PI3K/AKT/mTOR通路的影响。方法 150只雄性SD大鼠随机分为:预防组(对照组Ⅰ、模型组Ⅰ、给药组Ⅰ,每组20只)和治疗组(对照组Ⅱ、模型组Ⅱ、给药组Ⅱ,每组30只)。对照组Ⅰ/Ⅱ行气管暴露手术,气管内给以200μL/只的无菌等渗盐水,并分别于第2和14天开始腹腔注射等渗盐水(200μL/只);模型组Ⅰ/Ⅱ气管内灌注博来霉素(5 mg/kg),并分别于手术后第2和14天开始腹腔注射维生素D3的溶剂(0.1%乙醇和99.9%的丙二醇,1μL/g体重);给药组Ⅰ/Ⅱ气管内灌注博来霉素(5 mg/kg),并分别于手术后第2和14天开始腹腔注射1,25-(OH)_2D_3(2μg/kg体重)。大鼠气管内注射博来霉素建立IPF模型,给药组腹腔注射1,25-(OH)_2D_3进行预防和治疗。检测各组大鼠肺组织中羟脯氨酸的含量,分离肺泡Ⅱ型上皮细胞并用Fluo-3AM荧光负载,激光共聚焦显微镜检测细胞内Ca^(2+)浓度。RT-PCR方法检测PI3K、AKT、mTOR mRNA的表达水平。结果模型组Ⅰ/Ⅱ和给药组Ⅰ/Ⅱ中大鼠肺组织中羟脯氨酸的含量、肺泡Ⅱ型上皮细胞内Ca^(2+)浓度以及PI3K、AKT、mTOR mRNA表达,在各时间点与相应对照组Ⅰ/Ⅱ相比均明显升高(P<0.05或P<0.01);给药组Ⅰ/Ⅱ与模型组Ⅰ/Ⅱ相比,上述指标均有显著降低(P<0.05或P<0.01)。模型组Ⅰ/Ⅱ和给药组Ⅰ/Ⅱ中Ca^(2+)浓度与PI3K、AKT、mTOR mRNA表达之间具有显著正相关(r=0.598 8、r=0.623 0、r=0.6603,P<0.01;r=0.7012、r=0.6323、r=0.7403,P<0.01)。结论 PI3K-AKT-mTOR通路在大鼠IPF的发生发展中起重要作用,1,25-(OH)_2D_3可以降低肺泡Ⅱ型上皮细胞内Ca^(2+)的浓度,抑制PI3K-AKT-mTOR通路,进而抑制IPF的发生发展。

3D打印骨科钛合金的亚慢性全身毒性研究

目的评价3D打印骨科钛合金的亚慢性全身毒性。方法 40只SD大鼠随机分为2组,以尾静脉注射途径进行亚慢性全身毒性试验。通过对大鼠体质量、血液学、临床生化、脏器系数、组织病理学检测等指标,综合分析3D打印骨科钛合金的亚慢性全身毒性。结果两组大鼠均未观察到有生物学意义的异常指标。结论本研究评价的3D打印骨科钛合金未观察到亚慢性全身毒性。

大鼠肺纤维化和活性维生素D_3干预后P32和PKD1的表达及作用研究

目的探讨大鼠肺纤维化发生发展中透明质酸结合蛋白(P32)和蛋白激酶D1(PKD1)的表达及相互作用,以及活性维生素D_3(VD_3)干预后这2种因子表达的变化。方法90只清洁级雄性SD大鼠随机分成3组:对照组、模型组和治疗组。模型组和治疗组通过气管内注射博来霉素(BLM,5 mg/kg)的方法复制大鼠肺纤维化模型,对照组经气管注射等体积的生理盐水(500μl/kg)。术后第2天,治疗组腹腔注射VD_3(2μg/kg),模型组腹腔注射等量的VD_3的溶剂(99.9%丙二醇和0.1%乙醇),对照组腹腔注射等量的生理盐水,各组均注射1次/2 d。各组分别于术后第14、21、28天处死10只大鼠。通过检测大鼠肺组织羟脯氨酸含量来验证肺纤维化,应用实时聚合酶链反应(real-time PCR)和免疫组织化学技术分别检测大鼠肺组织中P32和PKD1的表达水平。结果纤维化早期(14 d),治疗组中P32和PKD1 m RNA和蛋白质表达量与模型组比较,差异有统计学意义(P<0.05),治疗组均高于模型组;相关性分析发现这2种基因的m RNA和蛋白质表达量具有相关性。结论在大鼠肺纤维化过程中,活性VD_3可能在纤维化早期促进P32和PKD1的表达,通过P32和PKD1在线粒体内的相互作用来实现抗氧化作用,进而抑制肺纤维化的发生发展。

ZDF与SD大鼠动脉粥样硬化形成及其磷脂酶A2表达的比较研究

目的观察ZDF和SD大鼠动脉粥样硬化（atherosclerosis，AS）形成和AS组织中磷脂酶A2（cPLA2、sPLA2、LP．PLA2）的表达情况。方法取ZDF（faffa）大鼠和SD大鼠各6只，用高脂饲喂加小剂量多次腹腔注射7×10^5U／kg维生素D3注射液，建立ZDF大鼠AS模型组和SD大鼠AS模型；另取ZDF（fa／＋）大鼠和SD大鼠各6只，分别作为ZDF大鼠对照组和SD大鼠对照组，饲喂普通饲料。检测造模前后GLU、TC、TG、HDL-C、LDL-C的含量和造模后血清Ca^2＋含量，并取AS大鼠腹主动脉进行HE染色和cPLA2、sPLA2、LP．PLA2的mRNA表达检测。结果ZDF大鼠AS模型组和SD大鼠AS模型组的空腹血糖、血脂水平和血清Ca2＋含量均显著升高（P〈0．01），腹主动脉出现典型的AS并伴明显的钙化，ZDF大鼠模型组血糖、血脂明显高于SD大鼠模型组，其AS病变也相对严重；ZDF大鼠AS模型组cPLA2和sPLA2的表达显著升高（P〈0．01），LP．PLA2的表达显著降低（P〈0．01）：而sD大鼠As模型组cPLA2、sPLA2、LP-PLA2的表达均显著升高（P〈0．01）。结论ZDF大鼠和SD大鼠进行高脂饲喂加小剂量多次注射维生素D3均能建立AS模型，ZDF（fa／fa）大鼠的AS病变相对严重，与其高血糖和高血脂状态有关；ZDF大鼠和SD大鼠中的PLA2的表达存在差异，这可能与SD大鼠AS形成的分子病理机制有关。

活性维生素D3干预保护2型糖尿病模型大鼠肝脏的作用机制

背景:活性维生素D3在2型糖尿病及其并发症发生发展中发挥着重要的调节作用。目的:探讨活性维生素D3干预保护2型糖尿病模型大鼠肝脏的作用及其机制。方法:将35只雄性SD大鼠随机分为正常对照组、糖尿病模型组和维生素D3干预组,后2组高脂高糖饮食并腹腔注射链脲佐菌素制备糖尿病大鼠模型。维生素D3干预组予以0.03μg/(kg·d)的骨化三醇灌胃(溶于花生油),正常对照组和糖尿病模型组以花生油灌胃。8周后麻醉处死,分离血清测定空腹血糖、空腹胰岛素、总胆固醇、三酰甘油,计算稳态模型胰岛素抵抗指数;留取肝组织,行苏木精-伊红染色、免疫组织化学染色、实时荧光定量PCR。结果与结论:1与糖尿病模型组相比,维生素D3干预组仅有三酰甘油、稳态模型胰岛素抵抗指数下降(P<0.05)。2与正常对照组相比,糖尿病模型组大鼠肝细胞肿胀、脂肪变性伴炎细胞浸润,JNK和C-Jun及其磷酸化形式的蛋白表达、JNK和C-Jun及其下游的肿瘤坏死因子α、白细胞介素1β的m RNA表达均升高(P<0.05);维生素D3干预组肝细胞肿胀及脂肪变性减轻,炎细胞浸润减少,同时上述全部因子的表达亦低于糖尿病模型组(P<0.05)。3结果证实,维生素D3保护2型糖尿病模型大鼠肝脏的作用机制可能与其下调JNK/C-Jun信号通路有关。