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Efficient and precise genomic deletion in rice using enhanced prime editing

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aBIOTECH 2024年第2期5卷 214-218页

作者： Mengyuan Liu Xiang Zhang Wen Xu Guiting Kang Ya Liu Xinxiang Liu Wen Ren Jiuran zhao Jinxiao Yang Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China

Efficient and precise genomic deletion shows promise for investigating the function of proteins in plant research and enhancing agricultural *** this study,we tested the PRIME-Del(PDel)strategy using a pair of prime editing guide RNAs(pegRNAs)that targeted opposite DNA strands and achieved an average deletion efficiency of 55.8%for 60 bp fragment deletions at six endogenous ***,as high as 84.2%precise deletion efficiency was obtained for a 2000 bp deletion at the OsGS1 site in transgenic rice *** add the bases that were unintentionally deleted between the two nicking sequences,we used the PDel/Syn strategy,which introduced multiple synonymous base mutations in the region that had to be patched in the RT *** PDel/Syn strategy achieved an average of 58.1%deletion efficiency at six endogenous targets,which was higher than the PDel *** strategies presented in this study contribute to achieving more accurate and flexible deletions in transgenic rice plants.

关键词： Prime editing Precise genomic deletion CRISPR Cas9

ECMpy 2.0:A Python package for automated construction and analysis of enzyme-constrained models

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Synthetic and Systems Biotechnology 2024年第3期9卷 494-502页

作者： Zhitao Mao Jinhui Niu Jianxiao zhao Yuanyuan Huang Ke Wu Liyuan Yun Jirun Guan Qianqian Yuan Xiaoping Liao Zhiwen Wang Hongwu Ma Biodesign Center Key Laboratory of Engineering Biology for Low-carbon ManufacturingTianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308China National Center of Technology Innovation for Synthetic Biology Tianjin300308China Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin300072China College of Biotechnology Tianjin University of Science and TechnologyTianjin300457China Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenChina Tianjin Agricultural College Tianjin300384China Haihe Laboratory of Synthetic Biology Tianjin300308China

Genome-scale metabolic models(GEMs)have been widely employed to predict microorganism ***,GEMs only consider stoichiometric constraints,leading to a linear increase in simulated growth and product yields as substrate uptake rates *** divergence from experimental measurements prompted the creation of enzyme-constrained models(ecModels)for various species,successfully enhancing chemical *** upon studies that allocate macromolecule resources,we developed a Python-based workflow(ECMpy)that constructs an enzyme-constrained *** involves directly imposing an enzyme amount constraint in GEM and accounting for protein subunit composition in ***,this procedure de-mands manual collection of enzyme kinetic parameter information and subunit composition details,making it rather *** this work,we’ve enhanced the ECMpy toolbox to version 2.0,broadening its scope to automatically generate ecGEMs for a wider array of *** 2.0 automates the retrieval of enzyme kinetic parameters and employs machine learning for predicting these parameters,which significantly enhances parameter ***,ECMpy 2.0 introduces common analytical and visualization features for ecModels,rendering computational results more user ***,ECMpy 2.0 seamlessly integrates three published algorithms that exploit ecModels to uncover potential targets for metabolic *** 2.0 is available at https://***/tibbdc/ECMpy or as a pip package(https://***/project/ECMpy/).

关键词： Enzyme-constrained model Python package Automated construction Multiple analysis functions

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巴丹吉林大沙山地区盐膜微地貌与形成机制

科学通报 2024年第17期69卷 2441-2453页

作者：赵景波马延东邵天杰陈宝群陕西师范大学地理科学与旅游学院西安710062 长安大学旱区地下水文与生态效应教育部重点实验室西安710054 陕西省林业科学院黄土高原水土保持与生态修复国家林草局重点实验室西安710082 陕西师范大学行星风沙科学研究院西安710119

通过野外调查和实验分析,在巴丹吉林沙漠沙山地区发现了盐膜弧形球粒台阶微地貌、直线形盐膜悬空台阶微地貌、盐膜蝌蚪形微地貌和盐膜针形微地貌等多种类型的独特微地貌.这些盐膜微地貌大多是过去没有认识到的微地貌新类型,对它们进行... 详细信息

通过野外调查和实验分析,在巴丹吉林沙漠沙山地区发现了盐膜弧形球粒台阶微地貌、直线形盐膜悬空台阶微地貌、盐膜蝌蚪形微地貌和盐膜针形微地貌等多种类型的独特微地貌.这些盐膜微地貌大多是过去没有认识到的微地貌新类型,对它们进行研究具有发展微地貌学和揭示该区水循环及水分平衡的重要意义.该区盐膜微地貌形成动力可分为4种,分别是大气降水在包气带细粒层中富集形成的地下弱径流、地下弱径流出露地表形成地表弱径流、强烈蒸发引起的水分运移和后期的风动力.该区存在的有效大气降水在粗粒层和细粒层中的差异分布是盐膜微地貌形成的关键条件,盐类的胶结是微地貌形成的直接因素.盐膜微地貌和弱径流分布表明,沙山地区沙层水分为正平衡,在降水经过蒸发与蒸腾损失之后,仍有剩余水分补给地下水和湖水.盐膜微地貌形成机制是:有效大气降水→入渗水的差异分配→粗粒贫水层与细粒富水层出现→地下弱径流产生→地表弱径流形成→地表弱径流被强烈蒸发→盐类沉淀与盐类胶结沙层→盐膜形成→细粒层变坚硬→风力侵蚀→粗粒层凹进→细粒层凸出→盐膜阶梯等微地貌形成.盐膜化学成分的能谱分析发现,在极端干旱气候条件下Nb2O3和TiO2明显富集,这两种成分的明显富集可作为指示极端干旱气候环境的新指标.这项研究将拓展人们对干旱区沙丘地貌和水循环的认知.

关键词：盐膜微地貌微径流新生盐水循环巴丹吉林沙漠

基于互穿网络技术构筑环境友好型聚合物电解质膜及其电化学性能

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精细化工 2024年第5期41卷 1092-1100页

作者：冉云松陈怡刘阳松赵振强马先果贵州理工学院化学工程学院贵州贵阳550003 贵州省普通高等学校能源化学特色重点实验室贵州贵阳550003

以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为反应型乳化剂,丙烯酸丁酯(BA)、丙烯腈(AN)和丙烯酸(AA)为单体,利用互穿网络技术通过乳液聚合法制备了环境友好型聚合物电解质膜(M-ABAA),采用FTIR、XPS、SEM、TEM和TG对M-ABAA进行了表征;通过CV、... 详细信息

以2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为反应型乳化剂,丙烯酸丁酯(BA)、丙烯腈(AN)和丙烯酸(AA)为单体,利用互穿网络技术通过乳液聚合法制备了环境友好型聚合物电解质膜(M-ABAA),采用FTIR、XPS、SEM、TEM和TG对M-ABAA进行了表征;通过CV、EIS和充放电测试考察以M-ABAA为电解质膜组装的CR2032电池的电化学性能。结果表明,当m(AMPS)∶m(BA)∶m(AA)∶m(AN)=1∶3∶2∶2时,制备的M-ABAA(M2)的离子电导率为0.98 mS/cm,抗拉强度为7.53 MPa,断裂伸长率为90.4%,吸液率为150%,热收缩率为4%。M2与目前锂离子电池主流的正负极材料(LiCoO_(2)、LiMn_(2)O_(4)、LiFePO_(4)、NCM811)具有较好的相容性,普适性较好。以M2为电解质隔膜,金属锂为负极,分别以LiCoO_(2)和石墨为正极组装成半电池,0.2 C倍率下的首次放电比容量分别为141.3和347.1 mA·h/g,100圈循环后容量保持率分别为94.8%和85.0%;2.0 C倍率下,放电比容量分别为119.8和239.0 mA·h/g。

关键词：聚合物电解质膜互穿网络技术锂离子电池有机电化学与工业

Metabolic and microbial changes in light-vented bulbul during recent northward range expansion

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Current Zoology 2024年第1期70卷 24-33页

作者： Yun Wu Ying Xiong Yanzhu Ji Yalin cheng Qianghui Zhu Xiaolu Jiao Yongbin Chang Na zhao Jing Yang Fumin Lei Gang Song Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing 100101China College of Life Science University of Chinese Academy of SciencesBeijing 100049China Department of Zoology College of Life scienceSichuan Agricultural UniversityYa'an 625099SichuanChina Henan Engineering Research Center of Bird-Related Outage Zhengzhou Normal UniversityZhengzhou 450044China School of Ecology and Environment Anhui Normal UniversityWuhu 241002AnhuiChina School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXian 710021China Centerfor Excellence inAnimal Evolutionand Genetics Chinese Academy of SciencesKunming 650223China

Endotherms recently expanding to cold environments generally exhibit strong physiological acclimation to sustain high body *** this process,gut microbes likely play a considerable role in host physiological functions,including digestion and *** light-vented bulbul Pycnonotus sinensis represents one such *** used to be restricted to the Oriental realm but expanded its distribution range north to the Palearctic areas during the past few ***,we explored the seasonal dynamics of the resting metabolic rate(RMR)and microbiota for local and newly colonized populations of the *** results showed that the mass-adjusted RMR and body mass were pos-itively correlated with latitude variations in both ***,the gut microbiota showed a corresponding variation to the northern cold *** the two northern populations,the alpha diversity decreased compared with those of the two southern *** differences were detected in dominant phyla,such as Firmicutes,Bacteroidetes,Proteobacteria,and Desulfobacterota in both *** core microbiota showed geographic differences in the winter,including the elevated relative abundance of 5 species in northern ***,to explore the link between microbial communities and host metabolic thermogenesis,we conducted a correlation analysis between microbiota and mass-adjusted *** found that more genera were significantly correlated with mass-adjusted RMR in the wintering season compared to the breeding season(71 vs.23).These results suggest that microbiota of the lighted-vented bulbul linked with thermogenesis in diversity and abundance under northward expansion.

关键词： bird body mass gutmicrobiota RMR season

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CPSO优化PNN的陀螺故障诊断方法

中国惯性技术学报 2024年第6期32卷 630-636页

作者：张华强贾明玉赵善飞芦男陈雨山东理工大学机械工程学院淄博255049 北京航天发射技术研究所北京100076

针对惯性导航系统中的陀螺仪输出信号非线性、故障特征不明显的问题,为提高惯导系统中惯性器件的故障诊断正确率,提出一种基于改进粒子群算法(PSO)优化概率神经网络(PNN)的陀螺信号故障诊断方法。首先,针对光纤陀螺运行过程中常见的四... 详细信息

针对惯性导航系统中的陀螺仪输出信号非线性、故障特征不明显的问题,为提高惯导系统中惯性器件的故障诊断正确率,提出一种基于改进粒子群算法(PSO)优化概率神经网络(PNN)的陀螺信号故障诊断方法。首先,针对光纤陀螺运行过程中常见的四种故障信号,建立数学模型并进行小波变换提取其故障特征系数;其次,使用Cubic混沌映射以及非线性递减的惯性权重系数对粒子群进行粒子更新,并用于概率神经网络的最优平滑因子选择;最后,训练概率神经网络对陀螺仪故障信号进行分类和诊断。离线测试结果表明,CPSO算法优化的PNN网络针对四种故障分类的平均正确率达到95.8%。

关键词：粒子群优化算法概率神经网络陀螺故障诊断

1,6-Conjugate addition of para-quinone methides using gem-diborylcarbanions: Practical access to gem-diborylalkanes bearing vicinal tertiary/quaternary stereocenters

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Green Synthesis and Catalysis 2024年第1期5卷 68-72页

作者： Pu-Zhang Zi Xing-Bang Liu Quan-Hong zhao Min He Yuan Huang Department of Medicinal Chemistry School of PharmacyXi'an Jiaotong UniversityXi'an710061China

A novel,efficient and pragmatic method to prepare gem-diboron products with vicinal tertiary/quaternary stereocenters using LiTMP-mediated 1,6-conjugate addition of gem-diborylalkanes to para-quinone methides was described for the first *** results showed that various gem-diboron products with vicinal tertiary and quaternary stereocenters could be formed within 15 min at ambient *** simple protocol has also been applied for the efficient synthesis of the analogue of Bedaquiline.

关键词： gem-Diborylalkanes Quaternary stereocenter Conjugate addition para-Quinone methides Organoboron compounds

耦合相变储能的火电机组集成系统控制策略优化及效果分析

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中国电机工程学报 2024年第18期44卷 7235-7246,I0012页

作者：王珠刘明赵永亮王朝阳严俊杰动力工程多相流国家重点实验室(西安交通大学) 陕西省西安市710049

提升火电机组调峰调频能力是构建新型电力系统的重要举措。该文从锅炉-汽轮机能流解耦角度出发,设计抽取部分中压缸排汽进行储热的相变储能系统,与火电机组耦合后形成机-炉-储集成系统,提出重构机-炉-储三主体负荷指令的控制策略,并以某... 详细信息

提升火电机组调峰调频能力是构建新型电力系统的重要举措。该文从锅炉-汽轮机能流解耦角度出发,设计抽取部分中压缸排汽进行储热的相变储能系统,与火电机组耦合后形成机-炉-储集成系统,提出重构机-炉-储三主体负荷指令的控制策略,并以某660 MW(P_(e0)=660 MW)超超临界机组为例进行效果评估。考虑中压缸排汽参数后,选取融化温度为117.7℃的赤藓糖醇为储能材料,研究抽汽比例对机组降负荷性能的影响。结果表明:当中压缸排汽的抽汽比例由0.00变为0.85时,机组等效降负荷速率由2.00%P_(e0)/min提升至5.13%P_(e0)/min,柔性明显增强;储能系统中储热量最大为118.73 GJ,储(火用)量最大为28.97 GJ;负荷指令重构后,系统瞬态过程中热效率增加,最大增加了1.85%,(火用)效率降低,最大降低了2.23%。

关键词：火电机组相变储能集成系统指令重构控制策略

数字技术驱动农产品企业商业模式数字化转型——基于价值共创的纵向案例研究

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管理案例研究与评论 2024年第4期17卷 562-579页

作者：戴炳钦范志明简兆权闽西职业技术学院财经商贸学院龙岩364000 华南理工大学工商管理学院广州510640 广西农垦集团有限责任公司南宁530022

现有关于中国农产品企业商业模式从机械化到数字化转型机制的研究较为缺乏。通过对南宁糖业股份有限公司2015—2022年商业模式转型进行纵向案例分析,研究发现:第一,耕种收和深加工构成中国农产品企业从机械化到数字化商业模式转型的两... 详细信息

现有关于中国农产品企业商业模式从机械化到数字化转型机制的研究较为缺乏。通过对南宁糖业股份有限公司2015—2022年商业模式转型进行纵向案例分析,研究发现:第一,耕种收和深加工构成中国农产品企业从机械化到数字化商业模式转型的两个关键阶段;第二,基于数字化的协同创建和协同运营构成驱动两个转型阶段的重要机制。在数字技术和运营能力不匹配的情境下,提出了农产品企业通过价值共创实现数字化商业模式转型升级的理论模型,不仅有助于推进商业模式数字化转型和价值共创两个领域的理论形成,而且可为制定数字化、智能化农业政策和农产品企业实行数字化运营模式转型创新提供实践启示。

关键词：数字技术农产品企业商业模式数字化转型价值共创