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糯玉米子粒硬度与淀粉合成相关酶动态变化及相互关系

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玉米科学 2024年第6期32卷 38-45页

作者：史亚兴董会刘辉徐丽樊艳丽俞嫒年史亚民卢柏山赵久然北京市农林科学院玉米研究所/玉米DNA指纹及分子育种北京市重点实验室北京100097

以鲜食糯玉米品种京科糯2000和苏玉糯2号为试验材料,比较授粉后不同时期淀粉合成相关酶活性、淀粉含量、含水量和子粒硬度的差异及各指标间的相互关系,利用Logistic方程比较两个品种子粒淀粉积累速率。结果表明,糯玉米子粒淀粉合成相关... 详细信息

以鲜食糯玉米品种京科糯2000和苏玉糯2号为试验材料,比较授粉后不同时期淀粉合成相关酶活性、淀粉含量、含水量和子粒硬度的差异及各指标间的相互关系,利用Logistic方程比较两个品种子粒淀粉积累速率。结果表明,糯玉米子粒淀粉合成相关酶AGPase活性和SSS活性对淀粉的合成具有重要的促进作用,且在品种间有差异。利用Logistic方程比较两个品种糯玉米子粒淀粉积累过程,分析表明,与苏玉糯2号相比,京科糯2000达到最大淀粉积累速率的天数(T_(max))延长1.62 d,淀粉活跃积累天数增加8.85 d,子粒淀粉积累速率最大时的生长量(W_(max))提高3.97%,最大淀粉积累速率(G_(max))降低12.60%。糯玉米子粒淀粉含量与子粒含水量呈极显著负相关,与子粒硬度呈极显著正相关。

关键词：糯玉米淀粉积累子粒含水量硬度

Effect of blank quenching on shear spinning forming precision of 2219 aluminum alloy complex thin-walled components

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Chinese Journal of Aeronautics 2023年第4期36卷 538-555页

作者： Zhixin li Mei ZHAN Xiaoguang fan Yunda dong Luopeng xu School of Science Civil Aviation Flight University of ChinaGuanghan 618307China State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of High-Performance Precision Forming

The quenching-spinning(Q-S)process,i.e.,shear spinning after blank quenching,has been increasingly utilized to form 2219 aluminum alloy complex thin-walled ***,the changes in material property,shape and stress of the blanks after quenching will affect the spin-ning forming *** this study,the rules and mechanisms of these effects are investigated based on a combined finite element(FE)model including blank quenching and component spinning *** results indicate that the increase of material strength and the existence of distortion of the quenched blank lead to a notable increase in the non-uniformity of the circumferential compres-sive stress in the spinning area and the increase of the flange swing height during *** changes result in an increase in the wall thickness and component-mandrel gap of the *** quenching residual stress has little effect on wall thickness and roundness but can noticeably reduce the component-mandrel *** is because that the existence of quenching residual stress of the blank can lead to the decrease of the maximum circumferential compressive stress of the workpiece in spinning and an obvious drop in the maximum compressive stress after reaching the stress *** distortion is the main factor affecting the ***,the opti-mized installation way of the blank for spinning is obtained.

关键词： 2219 aluminum alloy Complex thin-walled com-ponents Finite element analysis Quenching distortion Residual stress Shear spinning

Geochemical Characteristic of Charnockites in North Margin of North China Craton: Indicating the Significiant of the Neoarchean Tecnotic Event

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Acta Geologica Sinica(English Edition) 2019年第5期93卷 1354-1376页

作者： SHI Qiang FENG fan xu Zhongyuan liu Zhenghong dong Xiaojie li Gang College of Earth Sciences Jilin University

The Neoarchean charnockites of North margain of North China Craton(NCC) has become a hot topic into understanding the Early Precambrian basement. Although there is a broad consensus that charnockite is usually related to granulite facies metamorphism, whether its petrogenesis and tectonics characteristics remains controversial. Inclusions within hypersthene and garnet in charnockite are used to identify the peak granulite facies mineral assemblage, with the formation of Magnesian-charnockite attributed to anatexis of the protolith associated with this granulite facies metamorphism. The distribution of major and trace elements in charnockite is very uneven, significant depleted in liLEs(eg. Cs, U, Th) and HFSEs(eg. Nb, Ta, P and Ti), riched in Sr. Raising to the coexistence of Eu-enrichment and Eu-depletion type of REE patterns that influenced by the content of plagioclase and the remnants minerals of zircon and apatite. Comparative the petrography, geochemistry and geochronology data of Magnesian-charnockite indicate that the ratios of mafic pellites and basalts involved in anatectic melting are different by the upwelling of mantle magma, also resulting in the Eu anormals characteristics. The formation of the Magnesian-charnockite is closely connected with the subduction of the NCC oceanic crust(About ~2.5 Ga). However, Ferroan-charnockite may be the formed by the crystallization differentiation of the upwelling of mantle-derived shoshonitic magma(About ~2.45 Ga), with the lower crust material addition.

关键词： Neoarchean Magnesian–charnockite Ferroan–charnockite Metamorphic anatexis event NCC

Persistence and intergenerational transmission of differentially expressed genes in the testes of intracytoplasmic sperm injection conceived mice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第5期14卷 372-381页

作者： li-ya wang ning wang fang LE Lei li Le-jun li Xiao-zhen liu Ying-ming ZHENG Hang-ying LOU Xiang-rong xu Xiao-ming ZHU Yi-min ZHU He-feng HUANG fan JIN Key Laboratory of Reproductive Genetics (Zhejiang) Ministry of Educationand Centre of Reproductive Medicine Women's HospitalSchool of MedicineZhejiang University Department of Gynecologic Oncology Henan Cancer Hospital

Intracytoplasmic sperm injection (ICSI) is commonly used to solve male infertility problems. Previous studies showed that early environmental exposure of an embryo may influence postnatal development. To detect whether ICSI operations affect the reproductive health of a male or his offspring, we established assisted reproductive technologies (ART) conceived mouse models, and analyzed gene expression profiles in the testes of both ICSI and naturally conceived (NC) newborn F1 mice using micro-array analysis. Among the differentially expressed genes, we focused on the expression of eight male reproduction-related genes. Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) was used to analyze the expression of these genes in the testes of both adult and old F1 generation mice and adult F2 generation mice. Our results showed that down-regulated and somatic cell-expressed genes in newborn mice retained their differential expression patterns in adult and old F1 generation individuals, implying the persistence and fetal origin of the alteration in the expression of these genes. The intergenerational transmission of differential gene expression was observed, but most changes tended to be reduced in adult F2 generations. Controlled ovarian hyperstimulation (COH) and in vitro fertilization (IVF) mice models were added to explore the precise factors contributing to the differences in ICSI offspring. The data demonstrated that superovulation, in vitro culture, and mechanical stimulation involved in ICSI had a cumulative effect on the differential expression of these male reproductive genes.

关键词： Intracytoplasmic sperm injection Testis Intergenerational transmission

玉米大斑病菌铁载体合成基因簇鉴定及表达分析

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农业生物技术学报 2024年第5期32卷 1121-1131页

作者：岳浩峰赵天益李海笑闫秋静徐雅迪孟亚南曹志艳刘宁董金皋河北农业大学生命科学学院华北作物改良与调控国家重点实验室/河北省植物生理与分子病理学重点实验室河北农业大学植物保护学院

铁是微生物生长必需的元素，在氧代谢、电子转移以及DNA和RNA合成等过程中发挥重要作用，微生物主要依赖于铁载体吸收环境中的铁离子。铁载体作为微生物分泌的低分子量铁螯合物，协助机体运输铁离子。真菌主要利用非核糖体多肽合成酶编... 详细信息

铁是微生物生长必需的元素，在氧代谢、电子转移以及DNA和RNA合成等过程中发挥重要作用，微生物主要依赖于铁载体吸收环境中的铁离子。铁载体作为微生物分泌的低分子量铁螯合物，协助机体运输铁离子。真菌主要利用非核糖体多肽合成酶编码基因为核心的次级代谢物生物合成基因簇合成铁载体，本研究旨在明确玉米大斑病菌(Setosphaeria turcica)铁载体的合成基因簇以及关键基因的表达。利用铬天青(chrome azurol sulphonate, CAS)鉴定玉米大斑病菌合成铁载体的类型并利用AntiSMASH网站预测其生物合成基因簇，利用玉米大斑病菌孢子不同发育时期的转录组数据及qRT-PCR分析病菌侵染过程中铁载体合成基因簇中各关键基因的表达水平以及外源铁浓度对基因表达的影响。结果表明，玉米大斑病菌产生异羟肟酸盐型铁载体，在基因组中鉴定得到1个产生异羟肟酸盐铁载体的次级代谢物生物合成基因簇，由非核糖体多肽合成酶(nonribosomal peptide synthetase, NRPS)编码基因StNPS6为核心的12个铁载体合成相关基因组成。在玉米大斑病菌孢子萌发和侵染玉米叶片的过程中，基因簇中多个基因表达显著上调。与菌丝时期相比，侵染6 d后StNPS6表达量上调5.52倍，侵染9 d时后辅助合成基因StrhbE表达量上调24.12倍，编码转运相关蛋白的基因Stpmd1上调19.95倍。同时发现富铁和贫铁均对病菌的生长具有一定的抑制作用，且富铁情况下病菌黑色素合成受阻，培养基中铁含量差异导致基因簇中多个基因表达量显著变化，尤其是转运相关蛋白基因Stpmd1在富铁条件下表达量上升73.28倍。本研究为解析玉米大斑病菌铁载体的潜在作用提供了参考。

关键词：玉米大斑病菌铁载体次级代谢产物生物合成基因簇基因表达

A novel CHS/ALG bi-layer composite membrane with sustained antimicrobial efficacy used as wound dressing

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Chinese Chemical Letters 2010年第8期21卷 1011-1014页

作者： Yang dong Hong Zhuo liu Lu xu Gang li Zi ning Ma Fei Han Hui Min Yao Yah Hui Sun San Ming li School of Pharmaceutics Shenyang Pharmaceutical University Shenyang 110016 China China Criminal Police University Shenyang 110035 China

A membrane composed of an alginate（ALG） layer and a chitosan（CHS） layer with sustained antimicrobial efficacy was *** HC1（CIP） was incorporated into the ALG *** feature of the composite membrane was analyzed by scanning electron microscopy（SEM）.Water uptake capacity,in vitro drug release,and in vitro antimicrobial activity were *** composite membrane exhibited perfect binding characteristic between the two *** water uptake capacity of all the membranes was above 800%.The CIP could release from the composite membranes for 48 *** membrane could control the bacterial growth *** results suggested that this CHS/ALG composite membrane incorporated with CIP had the potential for wound dressing application.

关键词： Chitosan Alginate Composite membrane Ciprofloxacin HCl Sustained release Antimicrobial efficacy

Environmental remediation promotes the restoration of biodiversity in the Shenzhen Bay Estuary,South China

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Ecosystem Health and Sustainability 2022年第1期8卷 26-34页

作者： Hualin xu Ke liu Tianzhu ning Gu Huang Qianmei Zhang Yuelin li Mengqi wang Yiming fan Weili an lingbo Ji Qinfeng Guo Hai Ren Neilingding-Futian National Nature Reserve Administration Bureau of Guangdong ShenzhenChina Department of Ecology South China Botanical GardenChinese Academy of SciencesGuangzhouChina University of Chinese Academy of Sciences BeijingChina CSCEC Aecom Consultans Co. Ltd Shenzhen BranchShenzhenChina Core Botanical Gardens Chinese Academy of SciencesGuangzhouChina School of Physics and Optoelectronic Engineering Foshan UniversityFoshanChina Zhongkai College of Agricultural Technology GuangzhouChina Eastern Forest Environmental Threat Assessment Center USDA Forest ServiceRTPNCUSA

Background:Rapid urbanization has greatly changed land-use patterns in many estuarine areas around the world,including the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)resulting in serious water pollution and ecosystem *** City has conducted comprehensive ecological management and restoration in the Shenzhen Bay since *** natural vegetation consisting of mangroves,semi-mangroves,wetland plants,and terrestrial plants were restored from the bund to the inner bank of the Fengtang *** and sewage flow diversion systems were *** non-point source and point-source sewage are now treated in municipal sewage treatment plants,then naturally flow through the constructed wetland,and then through a natural wetland,restored natural embankment,and finally through mangrove communities substantially improving water ***:The restoration of the wetland has increased animal and microbial diversity and has supported the establishment of a complex and stable food *** water purification and habitat restoration,the number of alien invasive plants in the estuarine ecosystem has decreased,and the diversity of native species of birds,fish,macrobenthos,amphibians,and reptiles has ***:These improvements indicate that human beings and nature can coexist in support of the sustainable development of Shenzhen City.

关键词： Coastal city sewage treatment ecological restoration mangrove bird diversity

Synthesis and Characterization of Two New Organically Templated Open-framework Uranium Phosphites

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1380-1386页

作者： xu Jian-Fu li Hao-Hong CAO Yan-ning HUANG Chang-Cang ZHANG Han-Hui liu dong-Sheng YANG Qi-Yu SUN Rui-Qing College of Chemistry and Chemical Engineering Fuzhoi University Fuzhou Fujian 350002 China Department of Chemistry Jinggangshan College Ji ＇an Jiangxi 343009 China

Two organically templated uranium phosphites, （C4H12N）（UO2）（HPO3）（NO3）（Mr = 486.16） 1 and （C16H36N）2（UO2）2（H2PO3）2（HPO3）（NO3）2 （Mr= 1390.95） 2, were prepared by evaporation from aqueous solution of uranyl nitrate, phosphite acid and their respective organic ammonium hydroxids. Their structures were determined by single-crystal X-ray diffraction and further characterized by infrared and fluorescence spectroscopy. In 1, pentagonal [UO7] bipyramids share comers with three [HPO3]2- tetrahedra and one edge with a [NO3]- anion to form [（UO2）- （HPO3）（NO3）]^- ladder-like chains parallel to the b axis. The structure of 2 is also based upon one-dimensional anionic [（UO2）2（H2PO3）2（HPO3）（NO3）2]2-chains of comer-sharing penta- gonal [UOT] bipyramids with [H2PO3]- and [HPO3] tetrahedra, which is still unknown in structural chemistry of uranium so far. Crystal data for 1： monoclinic, space group C2/m, a = 21.808（7）, b = 6.9605（15）, c = 8.357（2） A, β = 98.327（15）°, V= 1255.2（6） A^3, Z = 4, Dc = 2.573 g/cm^3, F（000） = 888, μ = 13.086 mm^-1 the final R = 0.0418 and wR = 0.0906 （I 〉 2σ（I））; and those for 2： monoclinic, space group C2/c, a = 36.4549（8）, b = 14.5296（11）, c = 20.8253（11） A, β = 101.7440（8）°, V= 10799.7（10） A3, Z = 8, Dc= 1.711 g/cm^3, F（000） = 5424,μ = 6.144 mm^-1, the final R= 0.0368 and wR= 0.0865 （I〉 2σ（I））.

关键词： uranium phosphite organically templated crystal structure fluorescence

Reduction of Efficiency Droop and Modification of Polarization Fields of InGaN-Based Green light-Emitting Diodes via Mg-Doping in the Barriers

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Chinese Physics Letters 2013年第8期30卷 129-131页

作者： ZHANG ning liu Zhe SI Zhao REN peng wang Xiao-dong FENG Xiang-xu dong peng DU Cheng-Xiao ZHU Shao-Xin FU Bing-Lei LU Hong-Xi li Jin-Min wang Jun-Xi Research and Development Center for Semiconductor lighting Chinese Academy of SciencesP.O.Box 912Beijing 100083

We demonstrate that the Mg-doping in barriers can partially screen the polarization fields of InGaN-based green light-emitting *** photocurrent spectra show that the Mg-doping samples have smaller polarization fields and the blue shift of the peak with increasing current is *** reduction of polarization fields can be attributed to the screening of the impurity holes generated by the Mg atoms in the *** efficiency droop is sensitive to the Mg-doping concentration in barriers,while the sample with Mg concentration of 5×10^(19) cm^(-3) exhibits the lowest efficiency degradation of 12.4%at a high injection current.

关键词： polarization Efficiency doping