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Cellular apoptosis and Caspase-12 expression in a rat model of progressive spinal cord compression

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Neural Regeneration Research 2009年第8期4卷 570-576页

作者： Yijian Liang kejian wang Shanquan Sun Wei Li Jianhua Ran Guiqiong He Department of Human Anatomy College of Basic Medicine Chongqing Medical University Chongqing 400016 China Department of Orthopaedics Second People's Hospital of Chengdu Chengdu 610017 Sichuan Province China Institute of Neuroscience Chongqing Medical University Chongqing 400016 China

BACKGROUND： Studies have demonstrated that the mechanisms underlying cellular apoptosis signal transduction focus on two pathways： intracellular mitochondria and extracellular death receptor. The current evidence supports that signal transduction of cellular apoptosis also includes endoplasmic reticulum stress signal transduction. OBJECTIVE： To observe Caspase-12 expression and cellular apoptosis following ischemia in rats with progressive spinal cord compression, and to verify the influence of endoplasmic reticulum stress on the apoptosis induced by spinal cord injury. DESIGN, TIME AND SETTING： A randomized, controlled, animal trial was performed at the Institute of Neuroscience in Chongqing Medical University between January and October in 2006. MATERIALS： Immunohistochemical kit, diaminobenzidine, and TUNEL kit were purchased from Beijing Zhongshan Biotechnology, China; rabbit anti-rat Caspase-12 monoclonal antibody was provided by Santa Cruz, USA. METHODS： Sixty Wistar rats, aged 3-4 months, were randomly assigned to a model group （n = 50）, which underwent spinal cord compression in the L1 segment following L1 laminectomy and articular process excision to establish a model of progressive spinal cord compression, and a sham-surgery group （n = 10）, which underwent only laminectomy. Starting with the first day after surgery, the rats were locally anesthetized, the skin was opened, and the screw was rotated by 1/4 of a cycle, twice weekly. MAIN OUTCOME MEASURES： At 3, 7, 14, 21, and 28 days after surgery, rats from each group were anesthetized, and the spinal cords were resected. Pathological changes following spinal cord compression were determined using hematoxylin-eosin staining, Nissl dye, and transmission electron microscopy. The TUNEL method was used to observe neuronal apoptosis in the compressed spinal cord segments. Immunohistochemistry and Western blot were utilized to detect Caspase-12 expression in the compressed segments. RESULTS： Cellular swelling, neu

关键词： progressive spinal cord compression apoptosis Caspase-12 rats endoplasmic reticulum stress

差速螺旋啮合双转子端面型线的统一几何设计及模拟

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机械工程学报 2017年第3期53卷 51-56页

作者：王克俭汪廷飞北京化工大学机电工程学院北京100029

为了更全面描述啮合差速转子的端面,通过引入变符系数?,采用相对运动法,推导了适合同向和异向的差速转子端面型线的统一啮合方程。通过改变差速比或者头数比及其他参数,可以得到不同新型的转子端面型线。用此模型建立了差速比为3:1、同... 详细信息

为了更全面描述啮合差速转子的端面,通过引入变符系数?,采用相对运动法,推导了适合同向和异向的差速转子端面型线的统一啮合方程。通过改变差速比或者头数比及其他参数,可以得到不同新型的转子端面型线。用此模型建立了差速比为3:1、同向和异向的等径不等导程双螺旋转子混合段。应用Polyflow软件,有限元数值模拟了高密度聚乙烯熔体在两种啮合旋向下的流动混合效果。异向差速螺纹元件有长而窄的均匀停留时间,分布混合能力较好;同向差速螺纹元件的拉伸混合、剪切作用大,分散混合能力较强。

关键词：差速螺旋啮合双转子端面型线统一几何设计混合数值模拟

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人工创制植物无融合生殖的研究进展

科学通报 2020年第27期65卷 2998-3007页

作者：张燕王春王克剑中国水稻研究所水稻生物学重点实验室杭州310006

无融合生殖(apomixis)是指植物绕过正常减数分裂与受精过程形成克隆种子的一种无性生殖方式.无融合生殖具有固定杂种优势的潜力,长期以来一直是研究的热点.但是,由于其形成机制复杂一直未能取得突破.在深入研究植物有性生殖机制的基础上... 详细信息

无融合生殖(apomixis)是指植物绕过正常减数分裂与受精过程形成克隆种子的一种无性生殖方式.无融合生殖具有固定杂种优势的潜力,长期以来一直是研究的热点.但是,由于其形成机制复杂一直未能取得突破.在深入研究植物有性生殖机制的基础上,通过人工设计创制无融合生殖有望成为实现杂种优势固定的一个可能途径.研究发现,同步突变多个减数分裂关键基因可以将减数分裂过程转换为类似有丝分裂过程,产生与母本遗传背景完全一致的克隆配子(mitosis instead of meiosis,Mi Me);在Mi Me背景下引入特殊的基因组消除系或编辑诱导孤雌生殖的关键基因能够成功实现无融合生殖.本文对无融合生殖技术的研究进展进行了总结,并对今后无融合生殖技术的改良以及将其在作物育种中的应用进行了讨论.

关键词：水稻无融合生殖杂种优势减数分裂克隆种子

Detection of Huanglongbing(citrus greening) based on hyperspectral image analysis and PCR

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Frontiers of Agricultural Science and Engineering 2019年第2期6卷 172-180页

作者： kejian wang Dongmei GUO Yao ZHANG Lie DENG Rangjin XIE Qiang LV Shilai YI Yongqiang ZHENG Yanyan MA Shaolan HE Southwest University/Citrus Research Institute of Chinese Academy of Agricultural Sciences Chongqing 400712 China National Agricultural Technology Extension and Service Center Beijing 100125 China Chengdu Plant Quarantine Station Chengdu 610000 China Key Laboratory of Modern Precision Agriculture System Integration Research China Agricultural University Beijing 100083 China

Huanglongbing (HLB, citrus greening) is one of the most serious quarantine diseases of citrus worldwide. To monitor in real-time, recognize diseased trees, and efficiently prevent and control HLB disease in citrus, it is necessary to develop a rapid diagnostic method to detect HLB infected plants without symptoms. This study used Newhall navel orange plants as the research subject, and collected normal color leaf samples and chlorotic leaf samples from a healthy orchard and an HLB-infected orchard, respectively. First, hyperspectral data of the upper and lower leaf surfaces were obtained, and then the polymerase chain reaction (PCR) was used to detect the HLB bacterium in each leaf. The PCR test results showed that all samples from the healthy orchard were negative, and a portion of the samples from the infected orchard were positive. According to these results, the leaf samples from the orchards were divided into disease-free leaves and HLB-positive leaves, and the least squares support vector machine recognition model was established based on the leaf hyperspectral reflectance. The effect on the model of the spectra obtained from the upper and lower leaf surfaces was investigated and different pretreatment methods were compared and analyzed. It was observed that the HLB recognition rate values of the calibration and validation sets based on upper leaf surface spectra under 9-point smoothing pretreatment were 100% and 92.5%, respectively. The recognition rate values based on lower leaf surface spectra under the second-order derivative pretreatment were also 100% and 92.5%, respectively. Both upper and lower leaf surface spectra were available for recognition of HLB-infected leaves, and the HLB PCR-positive leaves could be distinguished from the healthy by the hyperspectral modeling analysis. The results of this study show that early and nondestructive detection of HLBinfected leaves without symptoms is possible, which provides a basis for the hyperspectral diagnosi

关键词： citrus HLB hyperspectral identification PCR

CRISPR-Cas系统在植物基因组编辑中的研究进展

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生物工程学报 2017年第10期33卷 1712-1722页

作者：王春王克剑中闰农业科学院中国水稻研究所水稻生物学重点实验室浙江杭州310006

基因组定点编辑技术是研究基因功能和生物体改造的重要工具。CRISPR-Cas(Clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins)系统是近年来发展的一种新型基因组编辑技术,该技术通过一段向导RNA和配套的核酸酶就可对特定的基因组序列进行定点编辑,具有简单高效、应用广泛的特点,受到了生物学家的广泛关注。本文着重介绍CRISPR-Cas系统在植物中的研究进展,包括CRISPR-Cas9系统在植物中的应用与完善、扩大基因组编辑范围的研究、Cas9切口酶和失活酶的拓展、特异性单碱基突变编辑系统的研究、无外源DNA污染的植物基因编辑技术的发展以及基因组编辑技术在作物育种上的应用等方面。同时也提出了还需解决的问题,并展望了基因组编辑系统在作物育种中的应用前景,为开展这一领域的研究工作提供参考。

关键词： CRISPR-Cas系统基因组编辑植物基因组作物遗传育种

The Role of OsMSH5 in Crossover Formation during Rice Meiosis

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Molecular Plant 2013年第3期6卷 729-742页

作者： Qiong Luo Ding Tang MO wang Weixiong Luo Lei Zhang Baoxiang Qin Yi Shen kejian wang Yafei Li Zhukuan Cheng College of Plant Protection Yunnan Agricultural University Kunming 650201 China State Key Laboratory of Plant Genomics and Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China

MSH5, a meiosis-specific member of the MutS-homolog family, is required for normal level of recombination in budding yeast, mice, Caenorhabditis elegans, and Arabidopsis. Here, we report the identification and characterization of its rice homolog, OsMSH5, and demonstrate its function in rice meiosis. Five independent Osmsh5 mutants exhibited normal vegetative growth and severe sterility. The synaptonemal complex is well installed in Osmsh5, while the chiasma frequency is greatly reduced to approximately 10% of that observed in the wild-type, leading to the homologous non- disjunction and complete sterile phenotype. OsMSH5 is predominantly expressed in panicles. Immunofluorescence studies indicate that OsMSH5 chromosomal localization is limited to the early meiotic prophase I. OsMSH5 can be loaded onto meiotic chromosomes in Oszip4, Osmer3, and hellO. However, those ZMM proteins cannot be localized normally in the absence of OsMSH5. Furthermore, the residual chiasmata were shown to be the least frequent among the zmm mutants, including Osmer3, Oszip4, hellO, and Osmsh5. Taken together, we propose that OsMSH5 functions upstream of OsZIP4, OsMER3, and HEIl0 in class I crossover formation.

关键词： OsMSH5 crossover meiosis rice.

Creep Behaviour of Wood Flour/Poly(vinyl chloride) Composites

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 440-447页

作者：贾明印王克俭 Institute of Plastics Machinery and Engineering Beijing University of Chemical Technology

The experimental creep data were focused on wood-flour （WF）/poly vinyl chloride （PVC） composites with the variations in additive concentrations of wood flour, silane coupling agent, organomodified montmorillonite （OMMT） and nano-cacium carbonate （nano-CaCO3）. Their effects were analyzed using the Four-element Burger Model incorporating microscopic mechanisms. Total creep strain was low with increasing WF while elastic strain was high and plastic flow strain was low in modeling. Modification of WF with silane was beneficial to creep resistance, so did adding low ratio of OMMT （1.5 wt%） and nano-CaCO3 in composites. Thus, it was effective in reducing creep either by stiffening the PVC matrix using rigid nano-particles or by improving their adhesion with resin. However, superfluous quantity of any additament did not benefit the improvement owing to either earlier destruction of their agglomerates or stress-concentrated cracks in the over-incrassated interface.

关键词： composite creep wood flour poly (vinyl chloride) nano-particle

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设计决策脉络挖掘方法

计算机辅助设计与图形学学报 2019年第6期31卷 1053-1060页

作者：刘继红王克剑王嘉骥北京航空航天大学机械工程及自动化学院北京100191 哈尔滨电气股份有限公司哈尔滨150028

为了更好地引导和启发设计者的思考,提出设计决策脉络概念.设计决策脉络是舍去设计试错过程并呈现设计主体思维因果关系发展路径的设计理性知识模型抽象表达.基于细粒度设计理性知识模型,提出设计决策脉络挖掘方法.该方法基于商空间理... 详细信息

为了更好地引导和启发设计者的思考,提出设计决策脉络概念.设计决策脉络是舍去设计试错过程并呈现设计主体思维因果关系发展路径的设计理性知识模型抽象表达.基于细粒度设计理性知识模型,提出设计决策脉络挖掘方法.该方法基于商空间理论对设计理性知识模型进行约简,构建分层递阶设计决策脉络模型,以支持设计者从不同粒度水平分析设计问题;通过改进的流形排序算法实现模型的语义约简,删除与设计主题相关度较低的知识片段以获取核心设计思考过程.最后通过构建原型系统,验证了文中方法是有效的.

关键词：设计理性设计决策脉络商空间理论流形排序

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基于过程挖掘的共享设计脉络提取方法

计算机辅助设计与图形学学报 2016年第11期28卷 1965-1972页

作者：王克剑刘继红北京航空航天大学机械工程及自动化学院北京100191

针对目前协同设计的研究缺少快速形成有效设计共识的方法,导致难以发现协同认知规律及共识形成的认知机理的问题,提出一种基于过程挖掘的共享设计脉络提取方法来获得设计共识,以支持利用设计理性知识的知识融合型协同设计.首先从单个设... 详细信息

针对目前协同设计的研究缺少快速形成有效设计共识的方法,导致难以发现协同认知规律及共识形成的认知机理的问题,提出一种基于过程挖掘的共享设计脉络提取方法来获得设计共识,以支持利用设计理性知识的知识融合型协同设计.首先从单个设计理性模型实例中提取设计脉络,并将其表达为Petri网模型;然后再应用改进α算法遍历各设计脉络,去除设计脉络中噪声对挖掘过程的影响,从而提取出共享设计脉络;最后将共享设计脉络转换为便于理解的共享设计理性模型.实例验证表明,该方法是有效的.

关键词：协同设计共享设计脉络设计理性过程挖掘