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无患子雄性不育品种‘琦蕊’不同发育时期雄花转录组分析

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生物技术通报 2024年第7期40卷 197-206页

作者：廖杨梅赵国春翁学煌贾黎明陈仲北京林业大学林学院林木资源高效生产全国重点实验室省部共建森林培育与保护教育部重点实验室国家能源非粮生物质原料研发中心北京100083 福建源华林业生物科技有限公司三明354500

【目的】探究无患子(Sapindus mukorossi Gaertn.)雄性不育品种‘琦蕊’雄花不同发育时期的细胞学特征及差异表达基因,为深入解析无患子雄性不育发生的分子机制提供理论依据。【方法】在观察雄花花药不同发育过程的细胞学特点基础上,进... 详细信息

【目的】探究无患子(Sapindus mukorossi Gaertn.)雄性不育品种‘琦蕊’雄花不同发育时期的细胞学特征及差异表达基因,为深入解析无患子雄性不育发生的分子机制提供理论依据。【方法】在观察雄花花药不同发育过程的细胞学特点基础上,进一步利用RNA-Seq技术分别对小孢子母细胞时期(T1)、四分体时期(T2)、单核小孢子时期(T3)的雄花进行转录组比较分析,筛选关键差异表达基因。【结果】‘琦蕊’绒毡层和内层细胞的持续膨大与增殖使得药室结构混乱,药室空间不足,最终导致无可育花粉产生。内源激素测定发现,茉莉酸水平在‘琦蕊’雄花发育过程中呈下降趋势。3个时期的转录组分析共筛选到2990个差异表达基因(differentially expressed genes,DEGs),其中T2_vs_T1中722个(516个上调,206个下调),T3_vs_T2中1741个(765个上调,976个下调)。GO和KEGG分析表明,这些DEGs主要富集在代谢过程、细胞分裂、花粉壁合成、激素信号转导等方面,共鉴定到32个花粉发育相关DEGs、27个激素合成及信号转导DEGs。随机选取9个DEGs进行RT-qPCR分析,结果与RNA-Seq数据趋势一致,证明转录组数据的准确性。【结论】绒毡层细胞持续增殖和内层细胞延迟退化不断挤压小孢子是导致无患子‘琦蕊’雄性不育发生的主要原因,物质代谢、细胞分裂、激素水平、花粉发育等相关基因在雄性不育发生过程中发挥重要作用。

关键词：无患子雄性不育转录组差异表达基因绒毡层细胞分裂茉莉酸

Graphitized Cu-β-cyclodextrin polymer driving an efficient dual-reaction-center Fenton-like process by utilizing electrons of pollutants for water purification

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Journal of Environmental Sciences 2023年第4期126卷 565-574页

作者： Weixiang liao Lai Lyu DiWang chun Hu Tong Li Key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of EducationInstitute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou 510006China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

Excessive consumption of energy and resources is a major challenge in wastewater ***,a novel heterogeneous Fenton-like catalyst consisting of Cu-doped graphenelike catalysts (Cu-GCD NSs) was first synthesized by an enhanced carbothermal reduction of β-cyclodextrin (β-CD).The catalyst exhibits excellent Fenton-like catalytic activity for the degradation of various pollutants under neutral conditions,accompanied by low H_(2)O_(2)*** results of structural characterization and theoretical calculations confirmed that the dual reaction centers (DRCs) were constructed on Cu-GCD NSs surface through C-O-Cu bonds supported on zero-valent copper species,which play a significant role in the high-performance Fenton-like *** pollutants that served as electron donors were decomposed in the electron-poor carbon centers,whereas H_(2)O_(2)and dissolved oxygen obtained these electrons in the electron-rich Cu centers through C-O-Cu bonds,thereby producing more active *** study demonstrates that the electrons of pollutants can be efficiently utilized in Fenton-like reactions by DRCs on the catalyst surface,which provides an effective strategy to improve Fenton-like reactivity and reduce H_(2)O_(2)consumption.

关键词： Fenton-like Dual reaction centers Graphene-like carbon Nanoscale zero-valent copper Pollutants degradation

A Hybrid Method of Domain Lexicon Construction for Opinion targets Extraction Using Syntax and Semantics

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Journal of Computer Science & Technology 2016年第3期31卷 595-603页

作者： chun liao Chong Feng Sen Yang He-Yan Huang Department of Computer Science and Technology Beijing Institute of Technology Beijing 100081 China Beijing Engineering Research Center of High Volume Language Information Processing and Cloud Computing Applications Beijing Institute of Technology Beijing 100081 China

Opinion targets extraction of Chinese microblogs plays an important role in opinion mining. There has been a significant progress in this area recently, especially the method based on conditional random field （CRF）. However, this method only takes lexicon-related features into consideration and does not excavate the implied syntactic and semantic knowledge. We propose a novel approach which incorporates domain lexicon with groups of syntactical and semantic features. The approach acquires domain lexicon through a novel way which explores syntactic and semantic information through Part- of-Speech, dependency structure, phrase structure, semantic role and semantic similarity based on word embedding. And then we combine the domain lexicon with opinion targets extracted from CRF with groups of features for opinion targets extraction. Experimental results on COAE2014 dataset show the outperformance of the approach compared with other well-known methods on the task of opinion targets extraction.

关键词： domain lexicon opinion targets extraction syntactic structure semantic role word embedding

基于化学学科核心素养的解决问题关键能力测评框架的构建与应用

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化学教育（中英文） 2024年第5期45卷 29-34页

作者：周瑶王西宇余淞发申燕廖春泉深圳外国语学校广东深圳518083 深圳市第二十二高级中学广东深圳518107 深圳市盐港中学广东深圳518083 深圳市教育科学研究院广东深圳518001 广州大学化学化工学院广东广州510006 南方科技大学附属中学广东深圳518109

基于《普通高中化学课程标准(2017年版2020年修订)》中化学学科核心素养水平和学业水平考试的命题建议,本研究以知识(Knowledge)输出水平和情境(Situation)加工水平相融合的视角分析描述学生在解决实际问题(Question)过程中所表现的关... 详细信息

基于《普通高中化学课程标准(2017年版2020年修订)》中化学学科核心素养水平和学业水平考试的命题建议,本研究以知识(Knowledge)输出水平和情境(Situation)加工水平相融合的视角分析描述学生在解决实际问题(Question)过程中所表现的关键能力(Ability),构建了“KS-Q-A”能力测评框架,并以该测评框架对2023年深圳市高三年级化学学科第一次调研考试的试题进行分析,测评诊断学生的能力水平,也进一步佐证了测评框架的合理性和科学性。

关键词：化学测评知识输出情境加工关键能力

Non-scanning systems for far-infrared radiation detection from laser-induced plasmas

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High Power Laser Science and Engineering 2015年第2期3卷 1-5页

作者： chun Li Guo-Qian liao Yu-Tong Li Beijing National Laboratory of Condensed Matter Physics Institute of Physics CAS IFSA Collaborative Innovation Center Shanghai Jiao Tong University

With the development of ultraintense terawatt(TW) and petawatt(PW) laser systems, powerful terahertz(THz) radiation from laser–plasma interactions has been reported. Plasma-based THz systems, which are usually operated at extremely low repetition rates, call for single-shot diagnostics. In this paper, various state-of-the-art single-shot detection methods are introduced or designed for measurements and applications involved in high-power plasma-based THz sciences.

关键词： laser–plasma interaction single-shot detection ter

基于自噬抑制剂3-MA介导的大叶蛇葡萄总黄酮提取物对人乳腺癌细胞增殖、凋亡的影响

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中国药理学通报 2024年第6期40卷 1115-1123页

作者：许诗怡廖思雨张天旭邹雪桂春张秀桥湖北中医药大学药学院湖北武汉430065

目的探讨抑制自噬时,大叶蛇葡萄总黄酮提取物(total flavonoid extract,TFE)对人乳腺癌细胞增殖、凋亡的影响及其作用机制。方法针对人宫颈癌细胞Hela、人肺癌细胞A549、人肝癌细胞SMMC-7721、人乳腺癌细胞MCF-7、MDA-MB-231及人正常肝... 详细信息

目的探讨抑制自噬时,大叶蛇葡萄总黄酮提取物(total flavonoid extract,TFE)对人乳腺癌细胞增殖、凋亡的影响及其作用机制。方法针对人宫颈癌细胞Hela、人肺癌细胞A549、人肝癌细胞SMMC-7721、人乳腺癌细胞MCF-7、MDA-MB-231及人正常肝细胞L-02,采用MTT法优选敏感细胞株;通过TFE与自噬抑制剂3-甲基腺嘌呤(3-methyladenine,3-MA)联合运用,采用MTT法检测其对敏感细胞增殖的抑制作用;透射电子显微镜及Hoechst 33258单染法观察细胞的形态学变化;Annexin V-FITC/PI双染法检测细胞凋亡率的变化;Western blot检测凋亡相关蛋白和通路蛋白(死亡受体途径、线粒体途径、内质网应激途径)的表达水平;免疫荧光法检测线粒体途径关键蛋白Cyt-c表达,并选择自噬激动剂雷帕霉素(rapamycin,RA)进行反向验证。结果TFE可浓度依赖性抑制人乳腺癌细胞增殖,MCF-7细胞为敏感细胞株,与TFE组相比,TFE+3-MA组在24、48、72 h对MCF-7细胞的抑制率均明显增加(P<0.01),细胞数量减少、间隙增大,凋亡小体增多,凋亡率升高(P<0.01),Bax/Bcl-2(P<0.01)、cleaved caspase-3(P<0.01)、Cyt-c(P<0.05)、FADD、cleaved caspase-12的表达量均升高,核内凋亡蛋白Cyt-c表达增加;TFE+RA组荧光减弱,逆转了TFE诱导的线粒体途径凋亡。结论TFE能明显抑制人乳腺癌细胞的增殖,抑制自噬时可能通过线粒体途径促进MCF-7细胞凋亡,激活自噬可逆转细胞凋亡。

关键词：大叶蛇葡萄总黄酮提取物抑制自噬乳腺癌细胞 MCF-7细胞增殖凋亡

喀斯特区与非喀斯特区的地表温度与近地表气温差异分析

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长江科学院院报 2024年第3期41卷 54-61,78页

作者：廖梦垚罗娅余军林王青石春茂徐雪贵州师范大学地理与环境科学学院贵阳550025 贵州师范大学贵州省喀斯特山地生态环境国家重点实验室培育基地贵阳550025 贵州省水利科学研究院贵阳550001

地表温度与近地表气温的关系是识别下垫面与近地表大气相互作用的重要依据,对维持能量良好循环与改善气候环境具有重要意义。喀斯特区的自然背景与非喀斯特区有明显差异,陆地-大气间能量传输的规律在两类地区具有差异。基于近邻成对像... 详细信息

地表温度与近地表气温的关系是识别下垫面与近地表大气相互作用的重要依据,对维持能量良好循环与改善气候环境具有重要意义。喀斯特区的自然背景与非喀斯特区有明显差异,陆地-大气间能量传输的规律在两类地区具有差异。基于近邻成对像元选择,获取贵州西南紫云、望谟两县2000—2018年的地表温度和近地表气温,并对比分析它们在喀斯特区与非喀斯特区的差异。结果表明:①就年平均状况而言,喀斯特区地表温度与近地表气温的差异及其波动性比非喀斯特区大,陆地-大气之间能量传输的稳定性为非喀斯特区大于喀斯特区。②从季节状况看,地表温度与近地表气温的差异在春、夏、秋三季为喀斯特区比非喀斯特区明显,冬季无明显差异;地表温度与近地表气温差异的波动性在冬季为喀斯特区大于非喀斯特区;喀斯特区陆地-大气之间能量传输的稳定性在4个季节均大于非喀斯特区。③从各月看,喀斯特区地表温度与近地表气温差异在各月均比非喀斯特区明显,差异波动性在4月份大于非喀斯特区,其余月份基本一致;除去3月份和4月份,其余各月的非喀斯特区陆地-大气之间能量传输均比喀斯特区稳定。结果可为研究气候变化、解析地表环境模式和保护生态环境等方面提供参考。

关键词：地表温度近地表气温差异喀斯特区非喀斯特区

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Morphologies of Al_4Sr Intermetallic Phase and Its Modification Property upon A356 Alloys

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Journal of Materials Science & Technology 2012年第6期28卷 524-530页

作者： Chengwei liao Jianchun chun Yang Li Rui Tu chunxu Pan School of Physics and Technology and Center for Electron Microscopy Wuhan UniversityWuhan 430072China Hunan Jinlianxing Specially Materials Technology Co.Ltd Yueyang 414005China

In general, the modification performance of AI-Sr master alloys is primarily dependent upon the morphologies and sizes of the AI4Sr intermetallic phase. In this paper, the crystal structure, morphologies, sizes, hardness and elastic modulus of AI4Sr in AI-Sr master alloys prepared from variant processes were studied by means of optical metallurgical microscope, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and nanoindentation system. The results revealed that the microstructures and modification performance of the AI4Sr phase were related to the preparation processes. That is to say, when a ＂direct reaction-hot extrusion＂ process was used, the AI4Sr phase exhibited a homogeneous distribution in the AI matrix with small size and roundish shapes, which ensured the AI-Sr master alloy wire advantages involving high recovery, good reproducibility, no delitescence of modification, no corrosion on equipments, and good workability. However, in the case of the traditional ＂direct reaction＂ process, the AI4Sr phase was in large size with shapes of rectangular stripe and plates, which limited the Sr content increasing due to the brittleness of the AI-Sr alloy. It was also found that the morphology and size of the AI4Sr phases changed during heat treatment at high temperature up to 600℃.

关键词： Intermetallics Modification Hot extrusion Heat treatment Microstructure

Performance Evaluation of Memory-Centric ARMv8 Many-Core Architectures:A Case Study with Phytium 2000+

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Journal of Computer Science & Technology 2021年第1期36卷 33-43页

作者： Jian-Bin Fang Xiang-Ke liao chun Huang De-Zun Dong College of Computer National University of Defense TechnologyChangsha 410073China

This article presents a comprehensive performance evaluation of Phytium 2000+,an ARMv8-based 64-core *** focus on the cache and memory subsystems,analyzing the characteristics that impact the high-performance computing *** provide insights into the memory-relevant performance behaviours of the Phytium 2000+system through *** the help of the well-known roofline model,we analyze the Phytium 2000+system,taking both memory accesses and computations into *** on the knowledge gained from these micro-benchmarks,we evaluate two applications and use them to assess the capabilities of the Phytium 2000+*** results show that the ARMv8-based many-core system is capable of delivering high performance for a wide range of scientific kernels.

关键词： many-core architecture memory-centric design performance evaluation