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植物激素对棉花蕾铃脱落的调控研究进展

作物学报 2025年第1期51卷 1-29页

作者：谢章书谢学方屠小菊刘爱玉董合忠周仲华湖南农业大学农学院/作物生理与分子生物学教育部重点实验室湖南长沙410128 中国热带农业科学院橡胶研究所海南海口571101 山东省农业科学院经济作物研究所山东济南250000

棉花蕾铃脱落是一个普遍存在的现象,有对逆境环境胁迫的主动适应性脱落,也有因品种遗传特性、环境条件、栽培措施以及生物和非生物胁迫被动的受损脱落。蕾铃脱落直接影响着棉花的产量,国内外现有公开报道多集中于20世纪50、60年代关于... 详细信息

棉花蕾铃脱落是一个普遍存在的现象,有对逆境环境胁迫的主动适应性脱落,也有因品种遗传特性、环境条件、栽培措施以及生物和非生物胁迫被动的受损脱落。蕾铃脱落直接影响着棉花的产量,国内外现有公开报道多集中于20世纪50、60年代关于乙烯和脱落酸对棉花蕾铃脱落影响的初步发现。结合其他植物的研究结果来看,蕾铃脱落似乎与生长素、赤霉素和细胞分裂素等促生长类激素的下降以及乙烯和脱落酸等抑制生长类激素的升高密切相关,激素在植物体内不仅介导新陈代谢过程,还协调着与信号通路相关的调控因子,在脱落过程中起着关键作用。本文从植物激素调控入手,综述了近年来包括脱落区形成和作用的分子调控机制以及各激素在棉花蕾铃脱落以及其他植物(生殖)器官脱落过程中的响应和调控机制等。发现目前以棉花蕾铃脱落为对象的研究非常匮乏,且多集中于少数激素对棉花生殖生长影响的有限研究,缺乏对导致蕾铃脱落的深层次机制的探究和解析。因此,未来研究方向应着重于探究棉花蕾铃脱落的遗传基础、发掘新的抗脱落基因资源和培育抗脱落棉花品种,同时加强在以棉花为模型植物下,蕾铃脱落与植物激素调节的关系研究,为提高棉花产量提供理论依据和技术支持。

关键词：棉花植物激素蕾铃脱落研究现状研究方向

Biological Systems:Reliable Functions out of Randomness

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Journal of Systems Science & Complexity 2021年第5期34卷 2036-2047页

作者： xie Liang-Liang University of Waterloo WaterlooOntarioCanada.Email:llxie@uwaterloo.ca.

What makes biological systems different from man-made systems?One distinction is explored in this paper:Biological systems achieve reliable functions through randomness,i.e.,by both mitigating and exploiting the effects of *** fundamental reason for biological systems to take such a random approach is the randomness of the microscopic world,which is dramatically different from the macroscopic world we are familiar *** substantiate the idea,bacterial chemotaxis is used as an example.

关键词： Bacterial chemotaxis biological systems feedback randomness reliable functions

加权共表达网络分析与机器学习识别类风湿关节炎滑膜中的关键基因

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中国组织工程研究 2025年第2期29卷 294-301页

作者：武英楷史高龙谢宗刚苏州大学附属第二医院江苏省苏州市215000 宁阳县第一人民医院山东省泰安市271000

背景:类风湿关节炎是一种全身的免疫相关性疾病,主要病理特点是关节滑膜炎性增生及关节软骨的破坏,其发病机制目前尚不明确,迫切需要发现新的具有高度敏感性和特异性的诊断标志物。目的:联合使用生物信息学技术及计算机学习算法,识别并... 详细信息

背景:类风湿关节炎是一种全身的免疫相关性疾病,主要病理特点是关节滑膜炎性增生及关节软骨的破坏,其发病机制目前尚不明确,迫切需要发现新的具有高度敏感性和特异性的诊断标志物。目的:联合使用生物信息学技术及计算机学习算法,识别并筛选类风湿关节炎患者滑膜中的关键基因,构建类风湿关节炎预测模型并进行验证。方法:从基因表达综合数据库中下载3个包含类风湿关节炎患者滑膜的数据集(GSE77298、GSE55235、GSE55457),GSE77298和GSE55235作为训练集,GSE55457作为测试集,共纳入66个样本,其中类风湿关节炎患者滑膜样本39个,正常滑膜样本27个。应用R语言筛选训练集中的差异基因,然后使用加权共表达网络将训练集中的基因模块化,选出关键模块中的特征基因,将差异表达基因和特征基因取交集,交集基因进入下一步机器学习。采用3种机器学习方法:最小绝对值收敛和选择算子算法、支持向量机-递归特征消除和随机森林算法对交集基因进一步分析获得枢纽基因,将枢纽基因再次相交即得到类风湿关节炎滑膜中的关键基因。以关键基因为变量构建预测类风湿关节炎的列线图模型,推测患者发生类风湿关节炎的危险程度,使用受试者工作特征曲线确定类风湿关节炎预测模型及其关键基因的诊断价值。结果与结论:①通过差异分析,训练集中共筛选出差异基因730个,加权共表达网络分析得到特征基因185个,两者交集基因159个;②最小绝对值收敛和选择算子发现枢纽基因4个,支持向量机-递归特征消除发现枢纽基因11个,随机森林发现枢纽基因5个,取交集后获得关键基因2个(TNS3、SDC1);③基于2个关键基因,在训练集及测试集种构建列线图,其校准预测曲线与标准曲线贴合较好,且预测类风湿关节炎发生的临床效能良好;④上述结果证实,基于生物信息及机器学习算法获得的TNS3和SDC1有可能成为类风湿关节炎诊断和治疗的关键靶点。

关键词：加权基因共表达网络机器学习算法类风湿关节炎关键基因预测模型

Engineering nanoparticle structure at synergistic Ru-Na interface for integrated CO2 capture and hydrogenation

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Journal of Energy Chemistry 2025年第1期 779-791页

作者： Hanzi Liu Ling Cen Xinlin xie Lei Liu Zhao Sun Zhiqiang Sun Hunan Engineering Research Center of Clean and Low-Carbon Energy Technology School of Energy Science and Engineering Central South University

The development of dual functional material for cyclic CO2capture and hydrogenation is of great significance for converting diluted CO2into valuable fuels,but suffers from kinetic limitation and deactivation of adsorbent and ***,we engineered a series of RuNa/γ-Al2O3materials,varying the size of ruthenium from single atoms to clusters/*** coordination environment and structure sensitivity of ruthenium were quantitatively investigated at atomic *** findings reveal that the reduced Ru nanoparticles,approximately 7.1 nm in diameter with a Ru-Ru coordination number of 5.9,exhibit high methane formation activity and selectivity at 340°*** Ru-Na interfacial sites facilitate CO2migration through a deoxygenation pathway,involving carbonate dissociation,carbonyl formation,and ***-situ experiments and theoretical calculations show that stable carbonyl intermediates on metallic Ru nanoparticles facilitate heterolytic C–O scission and C–H bonding,significantly lowering the energy barrier for activating stored CO2.

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Joint target assignment and power allocation in the netted C-MIMO radar when tracking multi-targets in the presence of self-defense blanket jamming

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Defence Technology（防务技术） 2023年第6期24卷 414-427页

作者： Zhengjie Li Junwei xie Haowei Zhang Jiahao xie Air and Missile Defense College Air Force Engineering UniversityXi'an 710051China Space Engineering University of Strategic Support Force Beijing 101416China

The netted radar system(NRS)has been proved to possess unique advantages in anti-jamming and improving target tracking *** resource management can greatly ensure the combat capability of the *** this paper,based on the netted collocated multiple input multiple output(CMIMO)radar,an effective joint target assignment and power allocation(JTAPA)strategy for tracking multi-targets under self-defense blanket jamming is *** architecture based on the distributed fusion is used in the radar network to estimate target state *** deriving the predicted conditional Cramer-Rao lower bound(PC-CRLB)based on the obtained state estimation information,the objective function is *** maximize the worst case tracking accuracy,the proposed JTAPA strategy implements an online target assignment and power allocation of all active nodes,subject to some resource *** the formulated JTAPA is non-convex,we propose an efficient two-step solution *** terms of the simulation results,the proposed algorithm can effectively improve tracking performance in the worst case.

关键词： Netted radar system MIMO Target assignment Power allocation Multi-targets tracking Self-defense blanket jamming

酸枣仁提取物调控miR-7b-3p/5-羟色胺1A受体表达促进骨生长

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中国组织工程研究 2025年第12期29卷 2450-2457页

作者：罗石任吴晓龙谢艳河南省洛阳正骨医院(河南省骨科医院) 河南省郑州市450000

背景:前期研究发现,酸枣仁提取物通过提高脑组织5-羟色胺1A受体(serotonin 1A receptor,5-HT1AR)表达,使之与5-羟色胺结合,延长小鼠慢波睡眠,促进生长激素的分泌,从而使骨生长。5-HT1AR作为一种蛋白质,其表达丰度受到miRNA的调控。作者... 详细信息

背景:前期研究发现,酸枣仁提取物通过提高脑组织5-羟色胺1A受体(serotonin 1A receptor,5-HT1AR)表达,使之与5-羟色胺结合,延长小鼠慢波睡眠,促进生长激素的分泌,从而使骨生长。5-HT1AR作为一种蛋白质,其表达丰度受到miRNA的调控。作者推测酸枣仁提取物可能通过miRNA调控5-HT1AR的表达从而发挥药物作用。目的:观察酸枣仁提取物通过干预小鼠脑组织中miR-7b-3p/5-HT1AR通路对骨骼生长的影响。方法:①将昆明种小鼠分为正常对照组、用药组(灌胃酸枣仁提取物0.320 mg/g),阳性对照组(灌胃酸枣仁皂甙0.013 mg/g)和酸枣仁提取物+5-HT1AR抑制剂组(灌胃酸枣仁提取物最后3 d同时每天侧脑室注射5-HT1AR选择性抑制剂P-MPPF 8μg),25 d后观察酸枣仁提取物对小鼠骨生长、血清生长激素水平及脑组织5-HT1AR表达的影响;②基因芯片法筛选由酸枣仁提取物引起的骨生长小鼠与普通小鼠脑组织差异表达的miRNAs,并通过PCR验证和双荧光素酶报告基因实验证实筛选的miR-7b-3p与5-HT1AR的调控关系;③体外培养小鼠脑皮质细胞并鉴定,利用Western blot法观察酸枣仁提取物对脑皮质细胞中5-HT1AR表达的影响;④将昆明种小鼠分为正常对照组、用药组、miR-7b-3p inhibitor组、用药+miR-7b-3p mimics组、阳性对照组,观察各组小鼠脑组织5-HT1AR表达及5-羟色胺与5-HT1AR结合活性;⑤将SD大鼠分为正常对照组、用药组、miR-7b-3p inhibitor组、用药+miR-7b-3p mimics组、阳性对照组,观察各组大鼠慢波睡眠的变化。结果与结论:①酸枣仁提取物可以促进小鼠体长、胫骨增长,促进生长激素分泌,提高脑组织5-HT1AR含量;②基因芯片筛选出差异表达的miRNAs个数为16个,其中上调有13个,下调有3个;生物信息学预测下调miR-7b-3p可以调控5-HT1AR表达,且双荧光素酶报告基因实验证实二者有直接调控关系;③酸枣仁提取物和沉默脑皮质细胞中miR-7b-3p表达可以引起5-HT1AR高表达;沉默miR-7b-3p后小鼠脑组织5-HT1AR表达、5-羟色胺与5-HT1AR结合活性及生长激素分泌均升高;过表达miR-7b-3p后小鼠脑组织5-HT1AR表达、5-羟色胺与5-HT1AR结合活性及生长激素分泌均降低;大鼠慢波睡眠期也相应延长或缩短。结果表明,酸枣仁提取物能够降低脑组织的miR-7b-3p水平,同时增加5-HT1AR的表达量。这种机制有助于延长慢波睡眠周期,并且促进生长激素的生成,对骨骼生长有积极影响,为使用酸枣仁提取物作为促进骨骼生长的潜在手段提供了科学依据。

关键词：酸枣仁提取物 miR-7b-3p 脑组织 5-羟色胺 5-羟色胺1A受体生长激素

人脐带间充质干细胞条件培养基及外泌体对肝癌细胞增殖、迁移、侵袭和凋亡的影响

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中国组织工程研究 2025年第7期29卷 1350-1355页

作者：金凯唐婷李美乐谢裕安广西中医药大学研究生院广西壮族自治区南宁市530002 广西壮族自治区妇幼保健院广西壮族自治区南宁市530002 广西出生缺陷及干细胞生物样本库重点实验室广西壮族自治区南宁市530002

背景:间充质干细胞可通过分泌含细胞因子、生长因子和外泌体的细胞外囊泡调节肿瘤微环境,对肿瘤细胞生物学行为进行精准调控。目的:研究人脐带间充质干细胞条件培养基及外泌体对肝癌细胞生物学特性的影响。方法:收集人脐带间充质干细胞... 详细信息

背景:间充质干细胞可通过分泌含细胞因子、生长因子和外泌体的细胞外囊泡调节肿瘤微环境,对肿瘤细胞生物学行为进行精准调控。目的:研究人脐带间充质干细胞条件培养基及外泌体对肝癌细胞生物学特性的影响。方法:收集人脐带间充质干细胞培养上清,通过高速离心并过滤获得人脐带间充质干细胞条件培养基;收集人脐带间充质干细胞培养上清,通过超高速梯度离心法提取人脐带间充质干细胞外泌体。使用PKH26标记人脐带间充质干细胞外泌体,与肝癌细胞MHCC97-H共培养,荧光显微镜观察MHCC97-H细胞摄取外泌体情况。通过CCK-8增殖实验、Transwell迁移和侵袭实验以及流式凋亡实验评估人脐带间充质干细胞条件培养基、人脐带间充质干细胞外泌体对肝癌细胞生物学功能的影响。结果与结论:(1)人脐带间充质干细胞外泌体可被MHCC97-H细胞摄取且主要分布于细胞质中;(2)人脐带间充质干细胞条件培养基处理后,MHCC97-H细胞的增殖、迁移和侵袭能力显著增强(P<0.001,P<0.05,P<0.01),凋亡能力显著下降(P<0.001);而人脐带间充质干细胞外泌体处理后,MHCC97-H细胞的增殖能力下降(P<0.001),迁移、侵袭及凋亡能力显著增强(P<0.001);(3)结果表明,人脐带间充质干细胞条件培养基具有促进MHCC97-H细胞增殖、迁移、侵袭和抑制凋亡的能力;而人脐带间充质干细胞外泌体则具有促进MHCC97-H细胞迁移、侵袭及凋亡和抑制增殖的能力。

关键词：肝癌人脐带间充质干细胞外泌体条件培养基增殖迁移侵袭凋亡

Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期 268-282页

作者： ZHENG Weilin WANG Qijiao XIAO Huahua CHEN Xiaoxiao xie Fan ZENG Wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace University State Key Laboratory of Fire Science University of science and Technology of China AVIC Shenyang Aircraft Design and Research Institute

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature（T=300-400 K）,initial pressure（P=0.1-0.3 MPa）,turbulence intensity（u'=1.0-2.7 m/s）,oxygen volumetric percentage(φ（O2）=15%-21%) and carbon dioxide volumetric percentage(φ（CO2）=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale（D6-D8） disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词：

Formation of FeNi metal nodules in the Jilin H5 chondrite,the largest stone meteorite in the world

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Acta Geochimica 2023年第6期42卷 961-970页

作者： Xiande xie Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

The Jilin H5 chondrite, the largest known stony meteorite in the world, with its No.1 fragment weighing1770 kg. It contains submillimeter-to centimeter-sized FeNi metal particles/nodules. Our optical microscopic and electron microprobe analyses revealed that the formation of metal nodules in this meteorite is a complex and long-term process, The early stage is the thermal diffusion-caused migration and concentration of dispersed metallic material along fractures to form root-hair shaped metal grains during thermal metamorphism of this meteorite. The later two collision events experienced by this meteorite led to the further migration and aggregation of metallic material into the shock-produced cracks and openings to form largersized metal grains. The shock-produced shear movement and frictional heating occurred in this meteorite greatly enhanced the migration and aggregation of metallic material to form the large-sized nodules. It was revealed that the metal nodule formation process in the Jilin H5 chondrite might perform in the solid or subsolidus state, and neither melting of chondritic metal grains nor shock-induced vaporization of bulk chondrite material are related with this process.

关键词： Jilin chondrite Metal nodules Thermal diffusion Shock metamorphism Shear movement Frictional heating