205 research outputs found
Research on the Arts Major of University Entrance Examination in China
艺术类专业招生考试是高校招生考试的一种特殊形式,对我国艺术人才的选拔和文化艺术水平的提升意义重大。近年来,艺术类专业招生考试日益升温,成为社会热点,也成为高考改革的重点和难点。本文从历史和现实的双重视角考察高校艺术类专业招生考试的发展过程,总结现状、特点与问题,并进行理论分析与探讨,提出改革建议,以促进普通高校艺术类专业招生考试改革的进一步深化与发展。 本论文主要包括绪论和正文四章。绪论部分从本文的研究缘起和意义谈起,提出相关问题,分析研究现状,对有关概念进行界定,并阐明研究思路与研究方法。第一章,以历史发展为线索,对我国清末民初、民国时期以及建国以后高等艺术教育和艺术院校招生考试的发展历程...Abstract Art major entrance examination is a special form of college entrance examination, which is great significance for selecting artistic talents and upgrading the level of culture & art. In recent years, art major entrance examination is growing up, which becomes the hot spots of society, as well as the focus and difficulty of the reform of college entrance examination. This paper uses histo...学位:教育学硕士院系专业:教育研究院_教育史学号:2572006115276
Intensity Distribution Design for Laser-Induced Thermal Loading Based on Numerical Simulation
To accomplish laser-induced thermal loading simulation tests for pistons,the Gaussian beam was modulated into multi-circular beam with specific intensity distribution.A reverse method was proposed to design the intensity distribution for the laser-induced thermal loading based on finite element(FE) analysis.Firstly,the FE model is improved by alternating parameters of boundary conditions and thermal-physical properties of piston material in a reasonable range,therefore it can simulate the experimental resul..
Calcium Distribution in the Stigma and Germinating Pollen of Lycium barbarum
用焦锑酸钾沉淀法对宁夏枸杞柱头和花粉中的钙离子分布进行了研究.结果显示,宁夏枸杞柱头表皮有一覆盖层,其中有许多含钙沉淀颗粒的小泡,当花粉落到柱头后从覆盖层中吸水,在萌发孔的表面上聚集了较多的钙沉淀颗粒.同时,花粉内部出现许多含钙的小液泡,使花粉体积增大,内部产生膨压,花粉萌发;生长在覆盖层中的花粉管顶端穿过覆盖层小泡时,附近聚集了较多的钙沉淀颗粒,在花粉管壁上也附着较多的细小钙沉淀颗粒.萌发的花粉粒中由大液泡占据,在其亚顶端的细胞质中,聚集较多钙沉淀颗粒的线粒体膨大形成了一些含钙沉淀颗粒的小液泡,由这些小液泡融合形成的大液泡,将花粉管细胞质挤到其顶端,使其极性生长.这是首次发现在植物柱头覆盖层中有钙离子的现象,从体内证明了钙离子在花粉萌发过程中的现象.讨论了枸杞柱头组织中钙的分布和花粉管的萌发与生长的关系.The stigma of Lycium barbarum is wet type and some material to be secreted to the surface of stigma to form a layer of tectum at anthesis.There were many vesicles in the tectum and numerous calcium precipitated grana were accumulated in the tectum vesicles.When pollen grains landed onto the stigma they began to hydrate and form many small vacuoles in which some calcium precipitated grana located,which made a swelling pressure in pollen.During pollen germinating in the tectum,the pollen tubes often traversed tectum vesicles and displayed many calcium precipitated grana on the tube wall,suggesting it to absorb calcium of the tectum vesicles.In the base of pollen tube some mitochondria with calcium precipitated grana swelled to form small vacuoles which fused to form a large vacuole.The pollen tube cytoplasm was pushed into the top of tube to make sure directional growth.This is first time to report that stigma tectum containing rich calcium in flowering plants.The calcium distribution in the stigma and pollen germination and tube growth were also discussed.国家自然科学基金项目(30670126
汉语全球教育史研究的国际视野
汉语全球教育史一直是当前学术界所关注的热点之一,进一步强化对此课题的研究不仅可以完善汉语教学在全球范围内的历史框架,同时也可以为当前汉语教学提供借鉴与经验。\"汉语全球教育史国际学术研讨会——世界汉语教育史研究会第九届年会\"的研讨内容涉及汉语教材研究、国际汉语传播、汉语本体与教学等多个领域,为当前学术界对汉语教育史的研究提供了新思路、新方法和新材料
聚乙烯吡咯烷酮对模拟混凝土孔隙液中钢筋的缓蚀效应
应用电化学阻抗谱和极化曲线测试技术,结合扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和拉曼(Raman)光谱分析,研究了表面活性剂聚乙烯吡咯烷酮(PVP)作为缓蚀剂对钢筋的缓蚀效应和机理.结果表明,PVP对pH值为11.0,含0.5 mol/L NaCl的模拟混凝土孔隙液中的钢筋具有良好的缓蚀作用,可有效抑制钢筋的腐蚀;PVP浓度变化对钢筋腐蚀行为有显著的影响,当浓度为25 mg/L时,PVP对钢筋的缓蚀效率达到89.1%;PVP通过在钢筋表面形成吸附膜来抑制钢筋的腐蚀.国家自然科学基金(批准号:21573182,51671163,21203158,21621091,21173177)资助~
基于均方根曲率和绝对曲率的三维人脸特征定位
三维面部特征的定位是三维人脸识别中的关键步骤,有效、简洁、清晰的轮廓特征是快速准确人脸识别的前提所在。本文首先简要介绍了目前主流的几种基于曲率的定位方法,然后通过进一步计算均方根曲率和绝对曲率,对于同样的图像得到了更好的特征定位效果
桑黄素对蘑菇酪氨酸酶的抑制作用
研究桑黄素(Morin)对蘑菇酪氨酸酶单酚酶和二酚酶活力的影响和抑制效应的结果表明:桑黄素对蘑菇酪氨酸酶的单酚酶和二酚酶活性均有抑制作用;导致单酚酶活力和二酚酶活力下降50%的抑制剂浓度(IC50)分别为0.08和1.02mmol/L;桑黄素对蘑菇酪氨酸酶的单酚酶的迟滞时间有明显的延长效应,0.175 mmol/L桑黄素使得单酚酶的迟滞时间从24 s延长到362 s,迟滞时间增加了14倍,酶的稳态活力下降了61.9%;桑黄素对二酚酶的抑制作用表现为竞争性可逆抑制作用,抑制常数为0.55 mmol/L
Fas ligand and Anti-human DR5 monoclonal antibody induce tumor cell lines apoptosis
目的探讨FasL、Anti-DR5mAb对肿瘤细胞Hela、BGC823、MCF-7、L342、H9101、D6的杀伤作用及机制。方法采用RT-PCR、MTT比色法、电泳、DNA倍体分析、Westernblot等方法。结果H9101、Hela细胞株DR5mRNA水平有表达,D6细胞无表达;H9101、L342细胞株FasmRNA水平有表达,D6细胞无表达。H9101、L342细胞株对FasL、Anti-DR5mAb敏感并呈剂量依赖性;MCF-7、BGC823细胞株对FasL敏感,对Anti-DR5mAb相对敏感。Hela对FasL相对敏感,对Anti-DR5mAb敏感;D6对两种凋亡诱导剂耐受。结论FasL、Anti-DR5mAb能不同程度地诱导肿瘤细胞凋亡,其机制与Fas、DR5、Caspase-8、Bcl-2的表达有关。
【英文摘要】 Objective:To study the cytotoxic effects on tumor cell lines Hela,BGC823,MCF-7,L342,H9101,D6 induced by Fas ligand and anti-human DR5 monoclonal antibodies(Anti-DR5 mAb) and the underlying mechanism.Methods:Fas/DR5 mRNA were detected by RT-PCR. Cytotoxicity exerted by FasL/Anti-DR5 mAb on tumor cell lines was measured by MTT colorimetry and the induced apoptosis was determined by agarose gel electrophoresis.Results:The expression of DR5 on BGC823 and Hela cells were higher and DR5 didn’t express in D6. The ...厦门大学科研启动基金(No.Z03103)资
维生素B_1对蘑菇酪氨酸酶抑制作用机理的研究
报道了维生素B1对蘑菇酪氨酸酶的单酚酶和二酚酶活力的影响以及抑制作用机理.研究结果表明,维生素B1(Vit B1)对蘑菇酪氨酸酶的单酚酶和二酚酶活性均有抑制作用.测定导致单酚酶活力和二酚酶活力下降50%的抑制剂浓度(IC50)分别为15和20 mmol/L.Vit B1对蘑菇酪氨酸酶的单酚酶的迟滞时间有明显的延长效应,21 mmol/L Vit B1使得单酚酶的迟滞时间从52 s延长到277 s.Vit B1对二酚酶的抑制作用表现为竞争性抑制类型,测定抑制常数(KI)为11.7 mmol/L
- …