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米曲霉β-半乳糖苷酶系的克隆表达与酶学特性分析

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食品工业科技 2016年第21期37卷 172-177,182页

作者：董自星贾超王君路福平王正祥天津科技大学化工与材料学院生物化工系天津300457 天津科技大学生物工程学院与工业发酵微生物教育部重点实验室天津300457

摘要：本研究通过对米曲霉的3个β-半乳糖苷酶基因O158、AO及O76进行了克隆与表达，成功构建了相应的重组菌GS115（pPIC－0158）、GS115（pPIC—AO）和GS115（pPIC－076），并获得相应的重组酶。进一步分析发现，重组酶O158、AO和O76的... 详细信息

摘要：本研究通过对米曲霉的3个β-半乳糖苷酶基因O158、AO及O76进行了克隆与表达，成功构建了相应的重组菌GS115（pPIC－0158）、GS115（pPIC—AO）和GS115（pPIC－076），并获得相应的重组酶。进一步分析发现，重组酶O158、AO和O76的最适作用pH分别为4．0、5．5和7．0；最适作用温度均为50℃；在pH5．0～7．5之间或30—40℃均较为稳定。Mn^2＋对重组酶O158、AO和O76有明显的激活作用，而Fe^2＋、Cu^2＋和Zn^2-则强烈抑制它们的酶活。O158、AO和O76只对乳糖具有水解与转苷活性，而且AO对乳糖的亲和力和催化效率均高于O158和O76。此外，在所试米曲霉菌种中不存在参照基因组中的β-半乳糖苷酶基因O42。本文系统地对米曲霉的3个β-半乳糖苷酶进行了异源表达及酶学性质的研究，为其大规模生产及工业化应用奠定了基础。

关键词：米曲霉 β-半乳糖苷酶分子克隆酶学性质

Anion-induced differential assembly and structural transformation of supramolecular coordination cages

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Chinese Chemical Letters 2024年第3期35卷 268-272页

作者： Shao-ping Zheng Yao-Wei Xu Pei-Yang Su Chen-Hui Liu Yin-Hui Huang Yu-Lin lu Zhang-Wen Wei Zhiwei Jiao Hai-Sen Xu Cheng-Yong Su MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510006China Institute of Environmental Research at Greater Bay Area Guangzhou UniversityGuangzhou 510006China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The intimate host-anion interactions will regulate thermodynamics and kinetics in the self-assembly of cationic cages mimicking biological ***,we report construction and transformation of three Pd(Ⅱ)-based metal-organic cages(MOCs)depending on different *** conversions of the lantern-shaped MOC-34 into either octahedral MOC-35 or tricapped trigonal prism MOC-36 are induced by BF_(4)^(–)or NO_(3)^(–),***-36 is kinetically favored and can undergo quantitative conversion to the thermodynamically preferred MOC-35 upon heating,accelerated by excess BF_(4)^(–)to motivate dissociative dynamics of Pd-vertices and lower activation barrier of cage *** guest encapsulation behaviors of MOC-35 and MOC-36 have also been *** results manifest a significance of host-anion dynamics beyond complementary anion template,shedding light on the understanding of intricate anion recognition in nature.

关键词： Supramolecular coordination cage Dynamic host-anion interactions Structural transformation Anion receptor Guest inclusion

Estimation of speed-related car body acceleration limits with quantile regression

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Railway Sciences 2024年第5期3卷 575-592页

作者： Jianli Cong Hang Zhang Zilong Wei Fei Yang Zaitian Ke Tao lu, Rong Chen ping wang Zili Li China Academy of Railway Sciences Corporation Limited Infrastructure Inspection Research InstituteBeijingChina School of Civil Engineering Beijing Jiaotong UniversityBeijingChina and Planning and Standard Research InstituteNational Railway AdministrationBeijingChina MOE Key Laboratory of High-Speed Railway Engineering Southwest Jiaotong UniversityChengduChina Department of Engineering Structures Delft University of TechnologyDelftNetherlands

Purpose–This study aimed to facilitate a rapid evaluation of track service status and vehicle ride comfort based on car body ***,a low-cost,data-driven approach was proposed for analyzing speed-related acceleration limits in metro ***/methodology/approach–A portable sensing terminal was developed to realize easy and efficient detection of car body ***,field measurements were performed on a 51.95-km metro *** from 272 metro sections were tested as a case study,and a quantile regression method was proposed to fit the control limits of the car body acceleration at different speeds using the measured ***–First,the frequency statistics of the measured data in the speed-acceleration dimension indicated that the car body acceleration was primarily concentrated within the constant speed stage,particularly at speeds of 15.4,18.3,and 20.9 m/***,resampling was performed according to the probability density distribution of car body acceleration for different speed domains to achieve data ***,combined with the traditional linear relationship between speed and acceleration,the statistical relationships between the speed and car body acceleration under different quantiles were *** concluded the lateral/vertical quantiles of 0.8989/0.9895,0.9942/0.997,and 0.9998/0.993 as being excellent,good,and qualified control limits,respectively,for the lateral and vertical acceleration of the car *** addition,regression lines for the speedrelated acceleration limits at other quantiles(0.5,0.75,2s,and 3s)were ***/value–The proposed method is expected to serve as a reference for further studies on speedrelated acceleration limits in rail transit systems.

关键词： Car body acceleration Track status monitoring Speed-related acceleration limit Quantile regression Vehicle ride quality

银川市黄河滩区土壤重金属污染特征、生态风险评价与来源解析

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环境科学 2024年第5期45卷 2971-2982页

作者：于路加马海军王翠平北方民族大学生物科学与工程学院银川750021 宁夏葡萄与葡萄酒技术创新中心银川750021 北方民族大学经济林遗传改良创新团队银川750021 林木资源高效生产全国重点实验室银川750004

为了解银川市黄河滩区土壤重金属污染现状及来源,采用电感耦合等离子体质谱法(ICP-MS)测定了银川市黄河滩区共92个采样点土壤样品中Zn、Cu、Cr、Pb、Ni、Cd、As和Mn这8种重金属的含量,采用富集因子、地累积指数法与潜在生态风险指数法... 详细信息

为了解银川市黄河滩区土壤重金属污染现状及来源,采用电感耦合等离子体质谱法(ICP-MS)测定了银川市黄河滩区共92个采样点土壤样品中Zn、Cu、Cr、Pb、Ni、Cd、As和Mn这8种重金属的含量,采用富集因子、地累积指数法与潜在生态风险指数法对重金属污染特征进行分析和评价,并结合相关性分析、绝对主成分-多元线性回归受体模型(APCS-MLR)、正定矩阵因子分解(PMF)模型和地统计学对土壤重金属进行来源解析.结果表明,Cu和Pb含量平均值低于银川市土壤背景值,Zn、Cr、Ni、Cd、As和Mn含量平均值分别是背景值的1.28、1.06、1.08、1.79、1.11和1.19倍,所测8种重金属元素含量平均值均低于农用地土壤污染风险筛选值;不同用地类型之间重金属含量平均值表现为:荒地>退耕地>林地>耕地;研究区Zn和Cd呈轻微富集,其余6种元素无富集;Cd属于中度潜在生态风险水平,其余重金属处于轻度水平;联合受体模型表明交通和农业等人为活动来源对Zn和Cd的贡献较大,其余重金属受土壤母质等自然源影响较大.研究结果可为银川市黄河生态保护与可持续发展提供科学依据.

关键词：黄河滩区重金属污染评价来源解析绝对因子得分-多元线性回归分析(APCS-MLR) 正定矩阵因子分解(PMF)

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甾体化合物RSA的11β-羟基化反应

生物工程学报 2001年第6期17卷 710-712页

作者：王敏路福平王风清蒋岳杜连祥天津轻工业学院食品工程系天津300222

Compound RSA 11β-Hydroxylation of %Curvularia lunata% was *** composition of hydroxylation products was *** was found that the conversion rate with protoplasts was increased conspicuously,the construction and quantity of hydroxylation products was not alteration,but the percentage was changed *** 14α-OH percentage of protoplasts was 3.03 -fold than that of mycelia, the 11α-OH percentage was decreased 60%,and the conversion ratio of 11β-OH was more 1.29-fold than that of the *** affected the percentage of hydroxylation products when 2 mg/mL polyoxins were added into the mycelia conversion system.

关键词： 11β-羟基化新月弯孢霉原生质体甾体化合物 RSA

Genome assembly of autotetraploid Actinidia arguta highlights adaptive evolution and enables dissection of important economic traits

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Plant Communications 2024年第6期5卷 173-192页

作者： Xue-Mei lu Xiao-Fen Yu Guo-Qiang Li Ming-Hao Qu Huan wang Chuang Liu Yu-ping Man Xiao-Han Jiang Mu-Zi Li Jian wang Qi-Qi Chen Rui Lei Cheng-Cheng Zhao Yun-Qiu Zhou Zheng-wang Jiang Zuo-Zhou Li Shang Zheng Chang Dong Bai-Lin wang Yan-Xiang Sun Hui-Qin Zhang Jie-Wei Li Quan-Hui Mo Ying Zhang Xin Lou Hai-Xu Peng Ya-Ting Yi He-Xin wang Xiu-Jun Zhang Yi-Bo wang Dan wang Li Li Qiong Zhang Wen-Xia wang Yongbo Liu Lei Gao Jin-Hu Wu Yan-Chang wang CAS Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhanHubeiChina Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhouGansuChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina Wuhan Frasergen Bioinformatics Co. LtdWuhanHubeiChina Institute of Soil and Fertilizer Anhui Academy of Agricultural SciencesHefeiChina College of Agricultural Sciences Xichang UniversityXichangSichuanChina Department of Horticulture Heilongjiang Academy of Agricultural SciencesHarbinHeilongjiangChina College of Life Sciences Langfang Normal UniversityLangfangHebeiChina Institute of Horticulture Zhejiang Academy of Agricultural SciencesHangzhouZhejiangChina Guangxi Institute of Botany Chinese Academy of SciencesGuilinGuangxiChina Xi’an Botanical Garden of Shaanxi Province Institute of Botany of Shaanxi ProvinceXi’anShaanxiChina Institute of Modern Agricultural Research Dalian UniversityDalianLiaoningChina Bioinformatics Center College of Plant Science and TechnologyBeijing University of AgricultureBeijingChina College of Agriculture Eastern Liaoning UniversityDandongLiaoningChina Dalian Institute of Chemical Physics Chinese Academy of SciencesDalianLiaoningChina State Environmental Protection Key Laboratory of Regional Eco-process and Function Assessment Chinese Research Academy of Environmental SciencesBeijingChina Hubei Hongshan Laboratory WuhanHubeiChina The New Zealand Institute for Plant and Food Research Limited AucklandNew Zealand

Actinidia arguta,the most widely distributed Actinidia species and the second cultivated species in the genus,can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit,rapid softening,and excellent cold *** evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still ***,we generated a chromosome-scale genome assembly of an autotetraploid male *** *** genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 116 *** and clustering of 101 geographically representative accessions showed that they could be divided into two geographic groups,Southern and Northern,which first diverged 12.9 million years *** underwent two prominent expansions and one demographic bottleneck from the midPleistocene climate transition to the late *** genomics studies using paleoclimate data enabled us to discern the evolution of the species’adaptation to different historical *** genes(AaCEL1,AaPME1,and AaDOF1)related to flesh softening were identified by multi-omics analysis,and their ability to accelerate flesh softening was verified through transient expression assays.A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome(Chr3)or autosomal chromosomes showed biased expression during stamen or carpel *** chromosome-level assembly of the autotetraploid *** genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of ***.

关键词： kiwiberry dioecism adaptive evolution paleoclimate GEA rapid softening

Gamma/Hadron Separation Method for the HADAR Experiment

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Research in Astronomy and Astrophysics 2024年第3期24卷 70-74页

作者： Yang-Zhao Ren Tian-lu Chen You-Liang Feng Dan-Zeng luo-Bu Yi-Qing Guo Cheng Liu Qi Gao Mao-Yuan Liu Xiang-Li Qian Ya-ping wang Zi-Hao Zhang Xin-Long Li Qing-Yuan Hou Heng-Jiao Liu Qing-Qian Zhou Shan-Jie Shu The Key Laboratory of Cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Intelligent Engineering Shandong Management University

Ground-based arrays of imaging atmospheric Cherenkov telescopes(IACTs)are the most sensitiveγ-ray detectors for energies of approximately 100 Ge V and *** such IACT is the High Altitude Detection of Astronomical Radiation(HADAR)experiment,which uses a large aperture refractive water lens system to capture atmospheric Cherenkov photons(i.e.,the imaging atmospheric Cherenkov technique).The telescope array has a low threshold energy and large field of view,and can continuously scan the area of the sky being observed,which is conducive to monitoring and promptly responding to transient *** process ofγ-hadron separation is essential in very-high-energy(>30 Ge V)γ-ray astronomy and is a key factor for the successful utilization of *** this study,Monte Carlo simulations were carried out to model the response of cosmic rays within the HADAR *** analyzing the Hillas parameters and the distance between the event core and the telescope,the distinction between air showers initiated byγ-rays and those initiated by cosmic rays was ***,a Quality Factor was introduced to assess the telescope’s ability to suppress the background and to provide a more effective characterization of its performance.

关键词： astroparticle physics-telescopes-methods data analysis

Interlayer Magnetic Interaction in the CrI_(3)/CrSe_(2) Heterostructure

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Chinese Physics Letters 2024年第5期41卷 85-89页

作者：王秋皓倪美燕李淑静郑法伟路洪艳张平 School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China Center for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and MeasurementSchool of PhysicsBeijing Institute of TechnologyBeijing 100081China Beijing Key Lab of Nanophotonics and Ultrafine Optoelectronic Systems School of PhysicsBeijing Institute of TechnologyBeijing 100081China College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China Institute of Applied Physics and Computational Mathematics Beijing 100088China

Based on first-principles calculations, we systematically study the stacking energy and interlayer magnetic interaction of the heterobilayer composed of CrI_(3) and CrSe_(2) monolayers. It is found that the stacking order plays a crucial role in the interlayer magnetic coupling. Among all possible stacking structures, the AA-stacking is the most stable heterostructure, exhibiting interlayer antiferromagnetic interactions. Interestingly, the interlayer magnetic interaction can be effectively tuned by biaxial strain. A 4.3% compressive strain would result in a ferromagnetic interlayer interaction in all stacking orders. These results reveal the magnetic properties of CrI_(3)/CrSe_(2) heterostructure, which is expected to be applied to spintronic devices.

关键词： strain stacking interlayer

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中日两国田径运动水平的比较分析

荆州师范学院学报 2002年第5期25卷 85-87页

作者：鲁国斌王平荆州师范学院体育系 434020

通过对 2 0 0 0年中日两国田径运动员的比较分析 ,男子方面 ,中国整体水平、世界排名均落后于日本 ,特别是径赛类项目 ,而田赛类中国队占上风 ;女子方面 ,中国则全面超过日本 ,投掷类项目更加明显。

关键词：比较分析中国日本田径运动员田径水平世界排名田径成绩