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基于JavaMail的Web Mail系统的实现 被引量:4
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作者 邱宏茂 许朝阳 盖磊 《计算机应用与软件》 CSCD 北大核心 2005年第6期36-37,111,共3页
本文提出一个在Solaris平台上以Sendmail、qpopper作为SMTP和POP3服务器,以Oracle高性能数据库为存储系统,以JavaMail、Servlet、JDBC为开发工具,实现高性能的WebMail系统。由于Java的跨平台性,使该系统具有很好的兼容性和扩展性。
关键词 JAVAMAIl Web l系统 SOlARIS平台 SENDMAIl POP3服务器 Servlet Oracle SMTP 存储系统 开发工具 JDBC 数据库 跨平台 扩展性 兼容性 性能
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Enhanced Phytoextraction of Cd and Cu in Ricinus communis L.with Chelators Related to Metal Concentrations in Soil Pore Water
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作者 Guo Jinghua Wang Shuifeng 《Journal of Northeast Agricultural University(English Edition)》 2025年第1期19-26,共8页
Cadmium(Cd)or excess copper(Cu)has a great impact in terms of toxicity on living organisms as it severely affects crop growth,yield and food security;thus,warranting appropriate measures for the remediation of Cd or C... Cadmium(Cd)or excess copper(Cu)has a great impact in terms of toxicity on living organisms as it severely affects crop growth,yield and food security;thus,warranting appropriate measures for the remediation of Cd or Cu polluted soils.Phytoextraction of heavy metal(HM)using tolerant plants along with organic chelators has gained global attention,and this study provided further insights into this issue.Pot experiments were performed to evaluate the effects of different types of chelators[ethylenediamine tetraacetic acid(EDTA),ethylenediamine disuccinic acid(EDDS)and citric acid(CA)]to improve the phytoextraction capacity of Ricinus communis L.for the metals Cd and Cu.Contaminated soil from a copper smelter was used in this study.A rhizon soil sampler was used to determine the metal concentrations in soil pore water.The results indicated that R.communis was an adequate candidate for chelator induced phytoextraction under the experimental conditions and that EDDS would be a good candidate chelator for the phytoextraction of Cu in soils.EDTA addition obviously improved the uptake of Cd and Cu in R.communis;however,it posed the greatest risk because the concentration of HMs in soil pore water was very high even after 40 days.Compared with EDTA and EDDS,CA had few effects on Cd or Cu uptake in R.communis.Linear relationships between the metal uptake in R.communis shoots and the maximum HM concentrations in soil pore water under HM,2.5,5,and 10 mmol·kg^(-1) treatments were typically observed.From the results of this study,it could be concluded that EDDS treatments played a promising role in increasing the uptake of Cd or Cu and reducing its phytotoxicity.EDDS application could be an effective approach for the phytoextraction of Cd or Cu from polluted soils by growing Ricinus communis L. 展开更多
关键词 environmental science soil contamination PHYTOREMEDIATION Ricinus communis l. CHElATOR
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Phylogenetic Analysis of Response of Sagittaria trifolia Linn.var.trifolia Genotypes of Northeast China to an Acetohydroxy Acid Synthase Inhibiting Herbicide
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作者 Sun Zhonghua Zhu He +5 位作者 Zou Yize Cao Shihan Wang Xingya He Fuli Ji Mingshan Han Yujun 《Journal of Northeast Agricultural University(English Edition)》 2025年第3期1-13,共13页
Sagittaria trifolia L.is a perennial aquatic herb that primarily reproduces clonally and through generative propagation.In recent years,S.trifolia has evolved a drastic resistance to acetohydroxy acid synthase(AHAS)-i... Sagittaria trifolia L.is a perennial aquatic herb that primarily reproduces clonally and through generative propagation.In recent years,S.trifolia has evolved a drastic resistance to acetohydroxy acid synthase(AHAS)-inhibiting herbicides in Northeast China.The phylogeographic patterns of S.trifolia with 31 purified resistance genotypes and five sensitive genotypes using chloroplast DNA(cpDNA)atpB-rbcL intergenic spacers were studied.Five haplotypes were characterized,and two of them were widely distributed in 36 genotypes.The dose response to bensulfuron-methyl showed that the GR50 ranged from 2.07 g a.i.·hm^(-2) to 220.15 g a.i.·hm^(-2).Sequencing of the AHAS gene indicated that 17 genotypes with the Pro197 mutation were distributed in haplotype 1,six genotypes with the Trp574 mutation were distributed in haplotype 3,and 13 genotypes with the wild AHAS gene were distributed in haplotypes 2,4 and 5.In the minimum-spanning network,the ancestral haplotypes 1 and 2 were widely distributed.Two primary clades were separated in the Bayes tree,and the result was consistent with the maximum likelihood tree. 展开更多
关键词 Sagittaria trifolia l. phylogeographic analysis HAPlOTYPE bensulfuron-methyl resistance
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辣椒抗烟草花叶病毒L^(3)基因的KASP标记转化及应用 被引量:1
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作者 陈灵芝 王兰兰 +1 位作者 高彦萍 余海涛 《中国蔬菜》 北大核心 2025年第4期66-71,共6页
辣椒中存在抗烟草花叶病毒属的基因位点L,本研究将与抗烟草花叶病毒L^(3)基因紧密连锁的SCAR标记PMFR11转化为KASP标记LJK,利用BC_(1)P_(1)群体进行有效性验证,基因型和抗、感病表型之间的一致率为92.4%。对标记LJK和与抗烟草花叶病毒L^... 辣椒中存在抗烟草花叶病毒属的基因位点L,本研究将与抗烟草花叶病毒L^(3)基因紧密连锁的SCAR标记PMFR11转化为KASP标记LJK,利用BC_(1)P_(1)群体进行有效性验证,基因型和抗、感病表型之间的一致率为92.4%。对标记LJK和与抗烟草花叶病毒L^(3)基因紧密连锁的SCAR标记PMFR21检测结果进行比较,LJK与PMFR21 PCR分型结果完全一致。研究表明LJK可以快捷、高效应用于辣椒抗烟草花叶病毒L^(3)基因的分子标记辅助选择。实际育种过程中,在辣椒苗期利用LJK淘汰纯合感病基因型单株,保留杂合抗性基因型单株继续进行L^(3)基因的回交转育,创制出了含有纯合L^(3)基因的抗性种质。 展开更多
关键词 辣椒 抗烟草花叶病毒 l^(3)基因 KASP标记lJK
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Erratum to:Evolution of microstructure and mechanical properties in multi-layer 316 L-TiC composite fabricated by selective laser melting additive manufacturing
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作者 Sasan YAZDANI Suleyman TEKELI +2 位作者 Hossein RABIEIFAR Ufuk TAŞCI Elina AKBARZADEH 《Journal of Central South University》 2025年第2期691-691,共1页
Because of an unfortunate mistake during the production of this article,the Acknowledgements have been omitted.The Acknowledgements are added as follows:Sasan YAZDANI would like to thank the Scientific and Technologic... Because of an unfortunate mistake during the production of this article,the Acknowledgements have been omitted.The Acknowledgements are added as follows:Sasan YAZDANI would like to thank the Scientific and Technological Research Council of Turkey(TÜB˙ITAK)for receiving financial support for this work through the 2221 Fellowship Program for Visiting Scientists and Scientists on Sabbatical Leave(Grant ID:E 21514107-115.02-228864).Sasan YAZDANI also expresses his gratitude to Sahand University of Technology for granting him sabbatical leave to facilitate the completion of this research. 展开更多
关键词 additive manufacturing microstructure mechanical properties fellowship program multi layer l TIC composite selective laser melting
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Tensile mechanical behavior of additively manufactured 316L austenitic stainless steels in liquid lead-bismuth eutectic and in air
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作者 WEN Tao ZHONG Zhi-huai +6 位作者 ZHU Sai-sai ZHOU Man-man WANG Pei CHAI Lin-jiang LIU Guo-qing PANG Bo GONG Xing 《Journal of Central South University》 2025年第8期2823-2840,共18页
In this work,tensile mechanical behavior of 316L steels fabricated by three different processing methods(casting,powder extrusion printing(PEP)and laser powder bed fusion(LPBF))was studied in the presence of liquid le... In this work,tensile mechanical behavior of 316L steels fabricated by three different processing methods(casting,powder extrusion printing(PEP)and laser powder bed fusion(LPBF))was studied in the presence of liquid lead-bismuth eutectic(LBE)and air at 350℃.The results show that all three steels tested in LBE are not subjected to evident degradation of tensile elongation to failure and strength compared to those tested in air,suggesting that LME does not occur regardless of the processing methods.The LPBF 316L steel exhibits the highest yield strength(420-435 MPa),followed by casting 316 L(~242 MPa)and PEP 316L(146-165 MPa).Ultimate tensile strength of three steels is comparable and ranges from 427 to 485 MPa.The PEP and casting 316L steels have similar total elongation to failure(i.e.,40.0%-43.8%),whereas this property decreases markedly to 18.6%-19.5% for the LPBF 316 L steel.The superior strength and relatively low ductility of the LPBF 316L steel can be attributed to nanosized dislocations trapped at cell structures which can produce a remarkable strengthening effect to the steel matrix.By contrast,due to massive residual micropores,the PEP 316L steel has the lowest strength. 展开更多
关键词 316l steel liquid lead-bismuth eutectic tensile properties powder extrusion printing laser powder bed fusion
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超声表面深滚压改善增材制造316L不锈钢微观组织和耐磨性
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作者 张涛 韩静 +2 位作者 曹超 黄笛 赵继云 《中国表面工程》 北大核心 2025年第3期121-129,共9页
增材制造316L不锈钢及其零部件具有高效、自由成型、优异力学和腐蚀性能等优势,为矿山机械及工程装备关键零部件、液压元件等结构—功能一体化制造奠定了基础。然而,增材制造316L不锈钢耐磨性不足,极大限制了其广泛应用。尝试采用超声... 增材制造316L不锈钢及其零部件具有高效、自由成型、优异力学和腐蚀性能等优势,为矿山机械及工程装备关键零部件、液压元件等结构—功能一体化制造奠定了基础。然而,增材制造316L不锈钢耐磨性不足,极大限制了其广泛应用。尝试采用超声表面深滚压(USSR)方法改善选区激光熔化(SLM)制造316L不锈钢的微观组织,进而提高其耐磨性。微观组织表征表明,USSR方法在SLM制造316L不锈钢表层形成梯度异质结构,表层晶粒细化至87 nm。室温磨损试验表明,相较于SLM试样,USSR试样在干摩擦和乳化液润滑条件下磨损体积分别降低了46.93%和49.58%。耐磨性提高主要来源于梯度异质结构带来的高硬度和变形抗力。研究结果为改善增材制造316L不锈钢及其零部件的耐磨性提供了新的途径。 展开更多
关键词 增材制造 选区激光熔化(SlM) 316l不锈钢 梯度 磨损
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非Lipschitz条件下Lévy噪声扰动的随机比例型微分方程的数值解
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作者 梁飞 张丽洁 《河南科技大学学报(自然科学版)》 北大核心 2025年第2期95-104,M0008,共11页
针对满足非Lipschitz条件的Lévy噪声扰动的随机比例型微分方程,首先证明了方程的精确解在非Lipschitz条件下以大概率存在于紧集中;其次运用Euler方法构造出方程的数值解,并证明了数值解在均方意义下依概率收敛于精确解;最后通过一... 针对满足非Lipschitz条件的Lévy噪声扰动的随机比例型微分方程,首先证明了方程的精确解在非Lipschitz条件下以大概率存在于紧集中;其次运用Euler方法构造出方程的数值解,并证明了数值解在均方意义下依概率收敛于精确解;最后通过一个例子验证了结论的有效性。 展开更多
关键词 随机比例型微分方程 lévy噪声 lIPSCHITZ条件 EUlER方法 数值解
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青鳉eef1a1l3基因的表达特征及抗体制备
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作者 黄岩 林淑婷 +2 位作者 邓菊 梁晶婕 陈天圣 《淡水渔业》 北大核心 2025年第1期60-68,共9页
青鳉(Oryzias latipes)是研究性别分化和生殖调控的重要模式鱼类,前期通过青鳉性腺转录组发现eef1a1l3 mRNA在卵巢中高表达,而在精巢几乎不表达,推测其参与性别分化和卵巢发育的调控。生物信息学分析显示,Eef1a1l3蛋白在硬骨鱼类中非常... 青鳉(Oryzias latipes)是研究性别分化和生殖调控的重要模式鱼类,前期通过青鳉性腺转录组发现eef1a1l3 mRNA在卵巢中高表达,而在精巢几乎不表达,推测其参与性别分化和卵巢发育的调控。生物信息学分析显示,Eef1a1l3蛋白在硬骨鱼类中非常保守。为探究eef1a1l3基因的功能,通过半定量PCR(SqRT-PCR)绘制了eef1a1l3基因在不同组织和早期不同发育时期的表达谱。通过抗原选取、原核表达、蛋白纯化以及动物免疫实验获取Eef1a1l3多克隆抗体,并对该抗体进行了特异性的检测以及效价的鉴定。结果显示,eef1a1l3 mRNA在成体组织中仅在卵巢特异表达,在早期胚胎发育阶段呈现母源性表达。制备的Eef1a1l3多克隆抗体与抗原结合的最大稀释倍数为1∶64000,显示出良好的免疫原性,并且Eef1a1l3蛋白在青鳉性腺中的卵巢而非精巢中有表达,这与mRNA表达模式一致。综上,eef1a1l3基因可能是早期胚胎发育和卵巢发育的重要调控因子,并且制备的Eef1a1l3多克隆抗体可以应用于青鳉及其他硬骨鱼类eef1a1l3基因功能的相关研究。 展开更多
关键词 青鳉(Oryzias latipes) eef1a1l3基因 多克隆抗体 表达模式 性别分化
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HPLC检测白血病细胞系CYP3A5活性方法的建立与应用 被引量:1
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作者 王婷 陈芳源 +3 位作者 韩洁英 钟济华 滕晔 欧阳仁荣 《上海第二医科大学学报》 CSCD 北大核心 2005年第5期440-442,446,共4页
目的建立白血病(AL)细胞系CYP3A5活性检测方法,研究化疗药对其活性的调控。方法HPLC法检测药物干预后AL细胞系CYP3A5活性。结果以1×106细胞、氢化考的松终浓度100μmol/L、孵育24h为AL细胞体外培养条件下氢化考的松6β-羟化活性检... 目的建立白血病(AL)细胞系CYP3A5活性检测方法,研究化疗药对其活性的调控。方法HPLC法检测药物干预后AL细胞系CYP3A5活性。结果以1×106细胞、氢化考的松终浓度100μmol/L、孵育24h为AL细胞体外培养条件下氢化考的松6β-羟化活性检测的孵育条件。K562细胞CYP3A5活性显著高于HL-60、NB4和Jurkat细胞。柔红霉素作用24h后K562细胞CYP3A5活性增高,48h后活性显著增高;而NB4与Jurkat细胞在其作用后活性无改变。地塞米松作用24h后Jurkat细胞CYP3A5活性显著增高,48h后活性又显著增高。全反式维甲酸作用24h后NB4细胞CYP3A5活性显著增高,72h后活性又显著增高。结论HPLC检测AL细胞体外培养条件下氢化考的松6β-羟化活性方法的建立可用于研究AL细胞CYP3A5活性。柔红霉素、地塞米松、全反式维甲酸的应用可诱导某些AL细胞株CYP3A5活性。 展开更多
关键词 CYP3A5 HPlC检测 白血病细胞系 Jurkat细胞 体外培养条件 K562细胞 全反式维甲酸 氢化考的松 Al细胞 柔红霉素 地塞米松 HPlC法 mol/l Hl-60 NB4细胞 24h 检测方法 活性检测 活性增高 72h后 干预后 细胞株 孵育 羟化 β-
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双圈连通图的L(2,1)-labelling(英文)
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作者 翟明清 吕长虹 《运筹学学报》 CSCD 北大核心 2008年第1期51-59,共9页
给定图G,G的一个L(2,1)-labelling是指一个映射f:V(G)→{0,1,2,…},满足:当dG(u,v)=1时,|f(u)-f(v)|≥2;当dG(u,v)=2时,|f(u)-f(v)|≥1。如果G的一个L(2,1)-labelling的像集合中没有元素超过k,则称之为一个k-L(2,1)- labelling.G的L(2,1... 给定图G,G的一个L(2,1)-labelling是指一个映射f:V(G)→{0,1,2,…},满足:当dG(u,v)=1时,|f(u)-f(v)|≥2;当dG(u,v)=2时,|f(u)-f(v)|≥1。如果G的一个L(2,1)-labelling的像集合中没有元素超过k,则称之为一个k-L(2,1)- labelling.G的L(2,1)-labelling数记作l(G),是指使得G存在k-L(2,1)-labelling的最小整数k.如果G的一个L(2,1)-labelling中的像元素是连续的,则称之为一个no-hole L(2,1)-labelling.本文证明了对每个双圈连通图G,l(G)=△+1或△+2.这个工作推广了[1]中的一个结果.此外,我们还给出了双圈连通图的no-hole L(2,1)-labelling的存在性. 展开更多
关键词 运筹学 频率分配问题 Distance-two labelling l(2 1)-labelling No-hole l(2 1)-labelling
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关于Euler gamma函数Γ与一类L-函数的代数微分无关性
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作者 李效敏 李奕萱 《中国海洋大学学报(自然科学版)》 北大核心 2025年第S1期106-109,148,共5页
本文研究了Euler gamma函数Γ与满足公理(Ⅰ)—(Ⅴ)的L-函数类S中的L-函数的代数微分无关性问题,证明了S中的L-函数与Euler gamma函数Γ不满足任意给定的非平凡代数微分方程。本文的主要结果推广了李宝勤和叶专2016年的相应结果,改进了... 本文研究了Euler gamma函数Γ与满足公理(Ⅰ)—(Ⅴ)的L-函数类S中的L-函数的代数微分无关性问题,证明了S中的L-函数与Euler gamma函数Γ不满足任意给定的非平凡代数微分方程。本文的主要结果推广了李宝勤和叶专2016年的相应结果,改进了陈玮和王琼2021年的相应结果。 展开更多
关键词 Euler gamma函数Γ l-函数类S 微分无关性 代数微分方程
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Block sparse compressed sensing with frames:Null space property and l_(2)/l_(q)(0
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作者 WU Fengong ZHONG Penghong QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第3期173-182,共10页
This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based ... This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based on the dictionary D.We establish that matrices adhering to the block D-NSP_(q)condition are both necessary and sufficient for the exact recovery of block sparse signals via l_(2)/l_(q)-synthesis.Additionally,this condition is essential for the stable recovery of signals that are block-compressible with respect to D.This D-NSP_(q)property is identified as the first complete condition for successful signal recovery using l_(2)/l_(q)-synthesis.Furthermore,we assess the theoretical efficacy of the l2/lq-synthesis method under conditions of measurement noise. 展开更多
关键词 Compressed sensing block sparse l2/lq-synthesis method null space property
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基于修正固有应变法的选区激光熔化成型316L钢块体残余应力预测 被引量:1
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作者 张博 耿鲁阳 +2 位作者 彭亚伟 王小威 巩建鸣 《南京工业大学学报(自然科学版)》 北大核心 2025年第1期56-65,共10页
选区激光熔化(SLM)制造过程中极高的温度梯度及快速熔化凝固现象会在部件中产生复杂的残余应力分布,进而导致部件的变形、开裂,以及使用中的提前失效。因此,对SLM成型零件的残余应力预测至关重要。将修正固有应变(MIS)法用于SLM成型316... 选区激光熔化(SLM)制造过程中极高的温度梯度及快速熔化凝固现象会在部件中产生复杂的残余应力分布,进而导致部件的变形、开裂,以及使用中的提前失效。因此,对SLM成型零件的残余应力预测至关重要。将修正固有应变(MIS)法用于SLM成型316L钢块体的残余应力预测。首先,采用热-力顺序耦合方法建立SLM成型的详细模型,从计算结果中提取固有应变并验证其准确性;随后,基于修正固有应变法建立10 mm×10 mm×10 mm的316L钢块体模型,模型由20个元层构成,每个元层中包含数个真实物理层;最后,通过逐层激活元层,并加载固有应变来模拟选区激光熔化成型过程,得到块体的应力-应变分布。以相同的工艺参数实际打印同尺寸的316L钢块体,使用X线衍射(XRD)法对块体的残余应力进行测量。结果表明:与XRD测量数据对比,修正固有应变法能够在较短时间内有效预测SLM成型316L钢块体的残余应力。 展开更多
关键词 316l 选区激光熔化(SlM) 固有应变 残余应力 元层
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QTL mapping for fiber quality and yieldrelated traits across multiple generations in segregating population of CCRI 70 被引量:3
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作者 DENG Xiaoying GONG Juwu +7 位作者 LIU Aiying SHI Yuzhen GONG Wankui GE Qun LI Junwen SHANG Haihong WU Yuxiang YUAN Youlu 《Journal of Cotton Research》 2019年第2期112-121,共10页
Background:Cotton is a significant economic crop that plays an indispensable role in many domains.Gossypium hirsutum L.is the most important fiber crop worldwide and contributes to more than 95%of global cotto n produ... Background:Cotton is a significant economic crop that plays an indispensable role in many domains.Gossypium hirsutum L.is the most important fiber crop worldwide and contributes to more than 95%of global cotto n production.Identifying stable quantitative trait locus(QTLs)controlling fiber quality and yield related traits are necessary prerequisites for marker-assisted selection(MAS).Results:A genetic linkage map was constructed with 312 simple sequence repeat(SSR)loci and 35 linkage groups using JoinMap 4.0;the map spanned 1 929.9 cM,with an average interval between two markers of 6.19 cM,and covered approximately 43.37%of the cotton genome.A total of 74 QTLs controlling fiber quality and 41 QTLs controlling yield-related traits were identified in 4 segregating generations.These QTLs were distributed across 20 chromosomes and collectively explained 1.01%?27.80%of the observed phenotypic variations.In particular,35 stable QTLs could be identified in multiple generations,25 common QTLs were con sistent with those in previous studies,and 15 QTL clusters were found in 11 chromosome segments.Conclusion:These studies provide a theoretical basis for improving cotton yield and fiber quality for molecular marker-assisted selection. 展开更多
关键词 QTl mapping Fiber quality Yield QUAlITY Multiple generations UPlAND cotton(Gossypium hirsutum l.)
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高分子量的聚L-谷氨酸的合成与表征 被引量:7
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作者 曹田 尹静波 +2 位作者 罗坤 陈红丹 陈学思 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2006年第2期369-371,共3页
采用三乙胺为催化剂经过氨基酸羧酸酐单体的开环聚合和脱保护基,制备了高分子量聚L-谷氨酸.实验结果表明。合成的高分子量聚L-谷氨酸黏均分子量控制在70000-350000左右.单体和引发剂的摩尔比n(A)/n(I)大于50时。分子量与n(A)... 采用三乙胺为催化剂经过氨基酸羧酸酐单体的开环聚合和脱保护基,制备了高分子量聚L-谷氨酸.实验结果表明。合成的高分子量聚L-谷氨酸黏均分子量控制在70000-350000左右.单体和引发剂的摩尔比n(A)/n(I)大于50时。分子量与n(A)/n(I)无关. 展开更多
关键词 l-谷氨酸 l-谷氨酸苄酯 聚-l-谷氨酸苄酯 聚-l-谷氨酸
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Decreased active cytokinin levels inhibited the cytokinin signaling pathways to increase the lateral root number in mepiquat chloride-treated cotton(Gossypium hirsutum L.)seedlings
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作者 ZHANG Man ZHANG Jiaqi +5 位作者 CHEN Yujie WU Yixuan SHI Yang XING Haiyan CHEN Xiaojiao WANG Baomin 《Journal of Cotton Research》 2025年第3期402-417,共16页
Background Mepiquat chloride(MC)is a widely used plant growth regulator in cotton(Gossypium hirsutum L.).It regulates endogenous hormone content and crosstalk to control plant height and promote lateral root(LR)develo... Background Mepiquat chloride(MC)is a widely used plant growth regulator in cotton(Gossypium hirsutum L.).It regulates endogenous hormone content and crosstalk to control plant height and promote lateral root(LR)development.However,the roles of cytokinins(CTKs)in the MC-induced increase in LR number in cotton seedlings remain unclear.Therefore,in this study,whole-genome transcriptome analysis was performed to elucidate the molecular mechanisms,CTK transformation,and CTK signaling pathway response to MC in cotton roots.Results In the present study,MC reduced the contents of the active CTK trans-zeatin(tZ)and N^(6)-isopentenyladenine(iP)but increased the levels of the nucleoside CTK trans-zeatin riboside(tZR)and N^(6)-isopentenyladenine riboside(iPR).RNA-seq data showed that the CTK biosynthesis genes GhIPTs and active CTK catabolism genes GhCKXs were obviously upregulated after MC treatment.The CTK-activating enzyme gene GhLOGs was repressed compared with the control.Furthermore,MC inhibited the expression of GhAHK4 and GhARR2/12,which are involved in the CTK signaling pathway,and activated the IAA-IAA14-ARF7/19 signaling module.Meanwhile,MC increased the expression levels of genes involved in sucrose synthesis,the cell cycle,cell division,and cell wall biosynthesis pathways.Silencing the GhCKX family separately decreased the LR number and active indole-3-acetic acid(IAA)level.The expression levels of GhPIN1,GhARF7,GhARF19,GhLBD16,GhLBD18,GhLBD29,and GhLBD33 were downregulated,but GhARR2/12 and GhIAA14 were upregulated.The total content of active CTKs was noticeably increased.The results of silencing the GhLOGs family were opposite to those of silencing GhCKXs.Silencing GhARR12 could upregulate GhPIN1 expression and increase LR number.In addition,the silenced GhCKXs,GhLOGs,and GhARR12 were less responsive to MCinduced LR growth than the control.Conclusion These results suggested that MC treatment could upregulate CTK-nucleoside biosynthesis and CTK metabolism genes to decrease active CTK levels,promoting crosstalk between CTKs and auxin signaling pathways to enhance LR initiation. 展开更多
关键词 AUXIN CYTOKININS Gossypium hirsutum l. Mepiquat chloride RNA-seq Seed soak Agroinoculation-Virus-induced gene silencing(VIGS)
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Combining ability of Egyptian cotton(Gossypium barbadense L.)reveals genetic potential for improved yield and fiber quality 被引量:1
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作者 Abdelghany Ahmed M. El-Banna Aly A.A. +5 位作者 Lamlom Sobhi F El-Sorady Gawhara A. Salama Ehab A.A. Ren Honglei Shaibu Abdulwahab S. Yehia Waleed M.B. 《Journal of Cotton Research》 CAS 2024年第2期109-122,共14页
Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivati... Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivation of enhanced hybrid plants with desired traits,such as high yield and fine fiber quality.In this study,the general combining ability(GCA)and specific combining ability(SCA)of yield and fiber quality of nine cotton parents(six lines and three testers)and eighteen F1 crosses produced using a line×tester mating design were analyzed.Results The results revealed significant effects of genotypes,parents,crosses,and interactions between parents and crosses for most of the studied traits.Moreover,the effects of both additive and non-additive gene actions played a notably significant role in the inheritance of most of the yield and fiber quality attributes.The F1 hybrids of(Giza 90×Aust)×Giza 86,Uzbekistan 1×Giza 97,and Giza 96×Giza 97 demonstrated superior performance due to their favorable integration of high yield attributes and premium fiber quality characteristics.Path analysis revealed that lint yield has the highest positive direct effect on seed cotton yield,while lint percentage showed the highest negative direct effect on seed cotton yield.Principal component analysis identified specific parents and hybrids associated with higher cotton yield,fiber quality,and other agronomic traits.Conclusion This study provides insights into identifying potential single-and three-way cross hybrids with superior cotton yield and fiber quality characteristics,laying a foundation for future research on improving fiber quality in cotton. 展开更多
关键词 Gossypium barbadense l. Combining ability Seed cotton yield Fiber quality Cluster analysis Path analysis
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miR-665靶向BCL 2L11调控武安山羊成肌细胞增殖 被引量:1
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作者 冯婧 盛辉 +5 位作者 张效生 郭晓飞 姚大为 李玉鹏 陈龙宾 张金龙 《畜牧兽医学报》 北大核心 2025年第2期582-590,共9页
旨在利用分子生物学方法探究miR-665靶向调控BCL 2L11对山羊成肌细胞增殖的影响。本研究选取1月龄和9月龄的健康山公羊各3只,各年龄段体重均接近且饲养环境相同。本试验通过RT-qPCR分析BCL 2L11在武安山羊不同组织中的表达情况;利用RT-q... 旨在利用分子生物学方法探究miR-665靶向调控BCL 2L11对山羊成肌细胞增殖的影响。本研究选取1月龄和9月龄的健康山公羊各3只,各年龄段体重均接近且饲养环境相同。本试验通过RT-qPCR分析BCL 2L11在武安山羊不同组织中的表达情况;利用RT-qPCR检测了不同月龄武安山羊背最长肌组织中BCL 2L11和miRNA-665的表达情况;构建了BCL 2L113′UTR野生型和突变型载体,以及miR-665 mimics和对照组,将其共转染到HEK293T细胞,通过使用双荧光素酶报告基因检测系统鉴定了miR-665与BCL 2L11存在靶向性关系。在山羊成肌细胞转染miR-665 mimic及阴性对照,采用RT-qPCR检测了细胞凋亡标志因子XIAP和Fas表达水平,同时利用EdU试验分析miR-665过表达对山羊成肌细胞增殖的影响。结果表明,BCL 2L11在背最长肌组织中高表达;miR-665和BCL 2L11在9月龄和1月龄山羊背最长肌组织中表达情况存在差异,miR-665在1月龄的表达量高于9月龄,而BCL2L11则相反,两者存在负调控现象;通过双荧光素酶报告分析显示,当转染过表达miR-665 mimic后,显著抑制了BCL 2L11荧光素酶的活性,同时靶基因BCL 2L11的mRNA表达水平也明显降低。为进一步验证miR-665的功能,转染miR-665 mimic后发现细胞凋亡标志基因XIAP与Fas的表达量也显著降低;EdU试验分析显示,过表达miR-665后促进了成肌细胞的增殖。综上所述,在山羊背最长肌组织中miR-665作为BCL 2L11的调控元件,能够显著抑制山羊成肌细胞中BCL 2L11的表达水平,当miR-665过表达后,能够促进成肌细胞的增殖情况。 展开更多
关键词 miR-665 BCl 2l11 肌肉 武安山羊 成肌细胞
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L-瓜氨酸与L-高瓜氨酸的合成 被引量:3
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作者 贾根光 张玲 +4 位作者 刘玲 尹翠 缑灵山 朱婕颖 刘毅 《精细化工》 EI CAS CSCD 北大核心 2010年第12期1213-1215,共3页
以L-鸟氨酸盐酸盐为原料与五水硫酸铜反应生成二鸟氨酸合铜保护α-NH2,用尿素对δ-NH2甲酰化得到二瓜氨酸合铜,后用二水合草酸脱α-NH2保护得到目标产物L-瓜氨酸,总收率49.5%。用同样的方法以L-赖氨酸盐酸盐为原料制备了L-高瓜氨酸,总收... 以L-鸟氨酸盐酸盐为原料与五水硫酸铜反应生成二鸟氨酸合铜保护α-NH2,用尿素对δ-NH2甲酰化得到二瓜氨酸合铜,后用二水合草酸脱α-NH2保护得到目标产物L-瓜氨酸,总收率49.5%。用同样的方法以L-赖氨酸盐酸盐为原料制备了L-高瓜氨酸,总收率53.5%。产物经IR、熔点、旋光确证。该方法具有操作方便、安全、经济和环保等特点。 展开更多
关键词 l-瓜氨酸 l-鸟氨酸盐酸盐 l-高瓜氨酸 l-赖氨酸盐酸盐 医药与日化原料
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