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Protective mechanisms of picroside Ⅱ on aquaporin-4 expression in a rat model of cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2010年第6期5卷 411-417页

作者： Zhen Li xinying xu Qin Li Meizeng Zhang Wei Shen Institute of Cerebrovascular Diseases Qingdao University Medical College Qingdao 266021 Shandong Province China Neurology Department of Affiliated Hospital Qingdao University Medical College Qingdao 266021 Shandong Province China Teaching and Research Center of Integrative Medicine Qingdao University Medical College Qingdao 266021 Shandong Province China

BACKGROUND： Aquaporin-4 （AQP-4） over-expression following cerebral ischemia results in cerebral edema. Picroside Ⅱ has been shown to exhibit a neuroprotective effect on neuronal apoptosis. However, few reports have addressed the neuroprotective mechanisms and therapeutic times following cerebral ischemic reperfusion injury. OBJECTIVE： To explore the neuroprotective effects and ideal treatment window for picroside Ⅱ treatment of middle cerebral artery occlusion and reperfusion injury in rats. DESIGN, TIME AND SETTING; A randomized, controlled, animal experiment was performed at Institute of Cerebrovascular Diseases, Qingdao University Medical College from September 2008 to May 2009. MATERIALS： Picroside II was purchased from Tianjin Kuiqing Medical Technology, China. METHODS： A total of 165 adult, healthy, male, Wistar rats were randomly assigned to sham-surgery （n = 15）, model （n = 75）, and treatment groups （n = 75）. Rats in the model and treatment groups underwent middle cerebral artery occlusion and reperfusion through the use of an intraluminal monofilament suture on the left external-internal carotid artery, The treatment group was injected with 1.0% picroside Ⅱ （10 mg/kg） into the tail vein, and the model and sham-surgery groups were injected with 0.1 mol/L phosphate buffered saline （250 μL）. MAIN OUTCOME MEASURES： Neurological functional scores were evaluated using the Longa＇s method; cerebral infarction volume was detected through the use of tetrazolium chlodde staining; cellular apoptosis was determined through the use of the in situ end-labeling method; aquaporin-4 expression was measured using fluorescence labeling analysis and reverse transcription polymerase chain reaction technique. RESULTS： At 0.5 hour following cerebral ischemic injury, neurological functional scores were low, and a small infarction focus was detected in the ischemic cortex of the model group. Along with prolonged ischemia and an increased number of apoptosis-positive cells, AQP-4 mRN

关键词： picroside Ⅱ cerebral ischemia and reperfusion apoptosis aquaporin-4 therapeutic time window neuroprotection

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Constraints of molybdenite Re-Os and scheelite Sm-Nd ages on mineralization time of the Kukaazi Pb-Zn-Cu-W deposit, Western Kunlun, NW China

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Acta Geochimica 2018年第1期37卷 47-59页

作者： Chengbiao Leng Yuhui Wang Xingchun Zhang Jianfeng Gao Wei Zhang xinying xu State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 China Guizhou Central Laboratory of Geology and Mineral Resources Guiyang 550018 China University of Chinese Academy of Sciences Beijing 100049China Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

The Kukaazi Pb-Zn-Cu-W polymetallic deposit, located in the Western Kunlun orogenic belt, is a newly discovered skarn-type deposit. Ore bodies mainly occur in the forms of lenses and veins along beddings of the Mesoproterozoic metamorphic rocks. Three ore blocks, KⅠ,KⅡ, and KⅢ, have been outlined in different parts of the Kukaazi deposit in terms of mineral assemblages. The KⅠ ore block is mainly composed of chalcopyrite, scheelite,pyrrhotite, sphalerite, galena and minor pyrite, arsenopyrite,and molybdenite, whereas the other two ore blocks are made up of galena, sphalerite, magnetite and minor arsenopyrite and pyrite. In this study, we obtained a molybdenite isochron Re–Os age of 450.5 ± 6.4 Ma(2σ,MSWD = 0.057) and a scheelite Sm–Nd isochron age of 426 ± 59 Ma(2σ, MSWD = 0.49) for the KⅠ ore *** are broadly comparable to the ages of granitoid in the region. Scheelite grains from the KⅠ ore block contain high abundances of rare earth elements(REE, 42.0–95.7 ppm)and are enriched in light REE compared to heavy REE, with negative Eu anomalies(δEu = 0.13–0.55). They display similar REE patterns and Sm/Nd ratios to those of the coeval granitoids in the region. Moreover, they also have similar Sr and Nd isotopes [ ^(87)Sr/ ^(86)Sr = 0.7107–0.7118;ε_(Nd)(t) =-4.1 to-4.0] to those of such granitoids, implying that the tungsten-bearing fluids in the Kukaazi deposit probably originate from the granitic magmas. Our results first defined that the Early Paleozoic granitoids could lead to economic Mo–W–(Cu) mineralization at some favorable districts in the Western Kunlun orogenic belt and could be prospecting exploration targets.

关键词： Molybdenite Re-Os Scheelite Sm–Nd REE Kukaazi Pb-Zn-Cu-W polymetallic deposit Western Kunlun orogenic belt

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Picroside Ⅱ down-regulates matrix metalloproteinase-9 expression following cerebral ischemia/reperfusion injury in rats

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Neural Regeneration Research 2010年第18期5卷 1403-1407页

作者： Xiang Li xinying xu Zhen Li Yunliang Guo Qin Li Xiaodan Li Zhen Zhou Department of Ultrasound Affiliated Hospital of Qingdao University Medical College Qingdao 266003 Shandong Province China Institute of Cerebrovascular Disease Qingdao University Medical College Qingdao 266003 Shandong Province China Yuhuangding Hospital Qingdao University Medical College Qingdao 266003 Shandong Province China Experimental Center of Surgery Qingdao University Medical College Qingdao 266003 Shandong Province China

Studies have shown that Picroside Ⅱ attenuates inflammatory reactions following brain ischemia through the inhibition of the TLR-4-NF-KB signal transduction pathway, and ameliorates cerebral edema through the reduction of aquaporin-4 expression. Matrix metalloproteinase-9 （MMP-9）, located downstream of the TLR-4-NF-KB signal transduction pathway, can degrade the neurovascular matrix, damage the blood-brain barrier to induce cerebral edema, and directly result in neuronal apoptosis and brain injury, Therefore, the present study further observed MMP-9 expression in the brain tissues of rats with cerebral ischemia/reperfusion injury following Picroside Ⅱ treatment. Results demonstrated that Picroside Ⅱ significantly reduced MMP-9 expression in ischemic brain tissues, as well as neuronal apoptosis and brain infarct volume, suggesting Picroside Ⅱ exhibits neuroprotection by down-regulating MMP-9 expression and inhibiting cell apoptosis.

关键词： Picroside Ⅱ cerebral ischemia/reperfusion injury apoptosis matrix metalloproteinase-9 rats neural regeneration

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激光自蔓延烧结Fe-Al合金及其成型过程温度场数值模拟

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稀有金属材料与工程 2016年第11期45卷 2873-2877页

作者：李刚许新颖葛少成辽宁工程技术大学辽宁阜新123000

对Fe40Al60粉末压坯进行激光点燃自蔓延烧结,利用XRD、金相、硬度等表征手段,分析烧结合金表层区、中部区和底部区的微观组织结构及宏观性能,并采用有限元分析方法,对Fe40Al60激光烧结过程的温度场进行数值模拟,得到了烧结过程温度场分... 详细信息

对Fe40Al60粉末压坯进行激光点燃自蔓延烧结,利用XRD、金相、硬度等表征手段,分析烧结合金表层区、中部区和底部区的微观组织结构及宏观性能,并采用有限元分析方法,对Fe40Al60激光烧结过程的温度场进行数值模拟,得到了烧结过程温度场分布云图和路径图。结果表明:表层区产物相主要为FeAl、Al_2O_3,中部区产物相为Fe_3Al、FeAl、Al_2O_3,底层区产物相为Fe_3Al、Al_2O_3和Fe;烧结合金表层区组织为条状,中部区组织为胞状,底层区组织为针状;表层区硬度HV为9010 MPa,中间层硬度HV为10 050 MPa,底层区硬度HV为9650 MPa。模拟结果表明:10 s时,表层区温度最高为1150 K,中部区温度为894.033 K,底层区温度最低为820.979 K。表明试样各区域物相与该区温度场模拟结果相一致。

关键词： Fe-Al金属间化合物激光自蔓延烧结 ANSYS软件温度场

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GmCRY1s modulate gibberellin metabolism to regulate soybean shade avoidance in response to reduced blue light

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Molecular Plant 2021年第2期14卷 298-314页

作者： Xiangguang Lyu Qican Cheng Chao Qin Yinghui Li xinying xu Ronghuan Ji Ruolan Mu Hongyu Li Tao Zhao Jun Liu Yonggang Zhou Haiyan Li Guodong Yang Qingshan Chen Bin Liu The National Key Facility for Crop Gene Resources and Genetic Improvement(NFCRI) Institute of Crop ScienceChinese Academy of Agricultural SciencesBeijingP.R.China College of Life Sciences Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical DevelopmentJilin Agricultural UniversityChangchunP.R.China State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTaianP.R China Key Laboratory of Soybean Biology of Chinese Ministry of Education Key Laboratory of Soybean Biology and Breeding/Genetics of Chinese Agriculture MinistryCollege of AgricultureNortheast Agricultural UniversityHarbinP.R China

Soybean is an important legume crop that displays the classic shade avoidance syndrome(SAS),including exaggerated stem elongation,which leads to lodging and yield reduction under density farming ***,we compared the effects of two shade signals,low red light to far-red light ratio(R:FR)and low blue light(LBL),on soybean status and revealed that LBL predominantly induces excessive stem *** used CRISPR-Cas9-engineered Gmcry mutants to investigate the functions of seven cryptochromes(GmCRYs)in soybean and found that the four GmCRY1s overlap in mediating LBL-induced *** GmCRY1s increase the abundance of the bZlP transcription factors STF1 and STF2,which directly upregulate the expression of genes encoding GA2 oxidases to deactivate GA1 and repress stem ***,GmCRY1b overexpression lines displayed multiple agronomic advantages over the wild-type control under both dense planting and intercropping *** study demonstrates the integration of GmCRY1-mediated signals with the GA metabolic pathway in the regulation of LBL-induced SAS in *** also provides a promising option for breeding lodging-resistant,high-yield soybean cultivars in the future.

关键词： cryptochrome soybean shade avoidance low blue light gibberellin

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Complexity Reduction of the Received Signal in the Presence of Multipath

Complexity Reduction of the Received Signal in the Presence ...

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第37届中国控制会议

作者： Kai Wang Lan Cheng xinying xu Dengao Li College of Electronical and Power Engineering Taiyuan University of Technology College of Big Data Taiyuan University of Technology

Multipath elimination is one of the main research topics in high-precision positioning systems. Existing multipath elimination algorithms are affected by the received signal data size to a large extent in terms of algorithm complexity. The conventional signal size reduction method based on auto-correlation function is influenced not only by sample frequency but also by coherent interval. Furthermore, it also limits the multipath elimination algorithms that can be used in post processing. To address these problems, three signal reduction algorithms, canonical components（CC）-based method, principle component（PC）-based method and the combination method of CC and PC, are analyzed comprehensively from the prospective of relative energy error and signal size. To improve the real-time performance of the PC method, the fast-PC method is proposed. Meanwhile, the suggested correlation number and correlation spacing are also discussed in this paper. The simulation results show that the combination method of CC and PC outperforms other methods and can reduce the signal size efficiently, which means that it can offer a smaller size source signal for the multipath elimination algorithms used in the post processing.

关键词： Multipath elimination Canonical components Principal components Relative energy error

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“331”教学模式在高中生物学教学中的应用

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生物学教学 2024年第1期49卷 25-26页

作者：许鑫滢广西北海市第七中学北海536000

“331”教学模式是基于提高学生核心素养培养的角度,自创的一种教学模式,着眼于提高课堂教学有效性。以高中蛋白质相关内容为例,介绍了该模式的实施步骤,通过适当地放手让学生自主学习,使得教师角色和学生学习方式也随之改变。为探索生... 详细信息

“331”教学模式是基于提高学生核心素养培养的角度,自创的一种教学模式,着眼于提高课堂教学有效性。以高中蛋白质相关内容为例,介绍了该模式的实施步骤,通过适当地放手让学生自主学习,使得教师角色和学生学习方式也随之改变。为探索生物学课堂教学的改革,提供了一种思路。

关键词： “331”教学方法课堂实践蛋白质生物学教学

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自我威胁刺激对返回抑制的影响

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心理科学 2017年第2期40卷 296-302页

作者：徐欣颖高湘萍上海师范大学教育学院上海200234 上海师范大学心理咨询与发展中心上海200234

使用线索-靶子范式,分别将面孔刺激作为线索(实验1)和靶子(实验2)呈现,考察自我扭曲面孔对返回抑制的影响。结果发现:自我扭曲面孔为线索时,与他人扭曲、他人中性面孔产生了实验性分离,自我扭曲面孔的返回抑制效应量最小;自我扭曲面孔... 详细信息

使用线索-靶子范式,分别将面孔刺激作为线索(实验1)和靶子(实验2)呈现,考察自我扭曲面孔对返回抑制的影响。结果发现:自我扭曲面孔为线索时,与他人扭曲、他人中性面孔产生了实验性分离,自我扭曲面孔的返回抑制效应量最小;自我扭曲面孔为靶子时,返回抑制消失。研究结果揭示:以自我扭曲面孔为代表的自我威胁刺激激活了威胁性自我概念,缩小了注意搜索范围,可能是导致人际紧张的潜在自我认知机制。

关键词：自我面孔自我威胁视觉搜索返回抑制注意偏向

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Neighborhood Rough Set Reduction with Improved Mayfly Optimization Algorithm

Neighborhood Rough Set Reduction with Improved Mayfly Optimi...

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2021中国智能自动化大会(CIAC2021)

作者： Lijuan Shi Zhou Feng Yiyu Sang Xinlin Xie xinying xu College of Electrical and Power Engineering Taiyuan University of Technology School of Electronic Information Engineering Taiyuan University of Science and Technology

Attribute reduction refers to selecting some of the most effective attributes from the original attribute sets to reduce the dimensionality of the dataset and optimize the attribute indicators of the system. Rough set theory has made good achievements in attribute reduction as dataset preprocessor, but the current methods are not enough to find the global best subset. The Mayfly algorithm is a new intelligent optimization algorithm, which mainly includes group gathering,crossing, mutation, wedding dance and random walking. In this paper, an attribute reduction algorithm of neighborhood rough set based on improved MA algorithm is proposed. Two Sigmoid mapping functions are used to binary encoding of the mayfly, the switching conditions of the two positions update strategies are set to control migration trend distribution of the mayfly. And then the neighborhood rough set is combined to find the best attribute subset. The UCI and OpenML datasets are used as experiment datasets. The experimental results verify the superiority of the proposed method in finding an optimal reduction. At the same time,the proposed method has higher classification accuracy and faster convergence speed.

关键词： Attribute reduction Rough set theory Mayfly algorithm Position update strategy

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全覆盖粒计算模型的粒化、知识逼近及其算子性质研究

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南京大学学报（自然科学版） 2015年第1期51卷 105-110页

作者：谢珺秦琴续欣莹太原理工大学信息工程学院太原030024

粒计算(GrC)作为处理不精确、不确定、不完备信息的重要工具,其基本思想是粒化、粒的运算和粒运算结果的融合.部分覆盖是粒计算理论框架中的一种重要模型,在电脑安全、搜索引擎和客户评估等领域具有潜在应用价值.全覆盖是部分覆盖的一... 详细信息

粒计算(GrC)作为处理不精确、不确定、不完备信息的重要工具,其基本思想是粒化、粒的运算和粒运算结果的融合.部分覆盖是粒计算理论框架中的一种重要模型,在电脑安全、搜索引擎和客户评估等领域具有潜在应用价值.全覆盖是部分覆盖的一种特例,已有的研究是从粗糙集理论的角度开展的,这是一种一般拓扑观念下的全覆盖.本文在pre-topology理论的框架下,从粒化、知识逼近和算子性质三个方面,首先介绍了邻域系统的相关定义,并在邻域系统基础之上提出了粒、全覆盖、全覆盖近似空间的概念;然后在全覆盖近似空间中利用已定义的粒重新诠释了一般拓扑中的内点和闭包算子,对全覆盖近似空间中的任意对象进行知识逼近,并用算例来说明;最后探究了全覆盖粒计算模型中这对逼近算子满足的基本性质,并证明了所提性质,为以后设计基于全覆盖粒计算模型的特征选择算法提供了理论基础.

关键词：粒计算全覆盖邻域系统内点算子闭包算子

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