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The NAC transcription factor LuNAC61 negatively regulates fiber development in flax (Linum usitatissimum L.)
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作者 Dongwei Xie Jing Li +5 位作者 Wan Li Lijun Sun Zhigang Dai Wenzhi Zhou Jianguang Su Jian Sun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期795-805,共11页
Flax is a crucial fiber crop that exhibits excellent textile properties and serves as a model plant for investigating phloem fiber development. The regulation of multiple genes significantly influences fiber developme... Flax is a crucial fiber crop that exhibits excellent textile properties and serves as a model plant for investigating phloem fiber development. The regulation of multiple genes significantly influences fiber development, notably involving NAC(NAM, ATAF1/2, CUC2) transcription factors in forming the fiber secondary cell wall(SCW).Overexpression of LuNAC61 in flax resulted in sparse top meristematic zone leaves and significantly reduced stem cellulose content. Scanning electron microscopy and staining observations revealed a significant reduction in fiber bundles. β-Glucuronidase(GUS) staining analysis demonstrated high activity of the LuNAC61 promoter in the bast fibers of the flax stem. Additionally, several members of the LuPLATZ and LuCesA families exhibited significant coexpression with LuNAC61. Subcellular localization indicated the presence of LuPLATZ24 protein in the nucleus and cytoplasm, LuNAC61 protein exclusively in the nucleus, and LuCesA10 in the nucleus and endoplasmic reticulum. LuPLATZ24 positively regulates LuNAC61, whereas LuNAC61 negatively affects LuCesA10, suggesting the involvement of a metabolic network in regulating flax fiber development. In conclusion, this study provides a critical opportunity for a comprehensive and in-depth analysis of the mechanisms governing flax fiber development and the potential use of biotechnology to enhance flax fiber yield. 展开更多
关键词 FLAX fiber development lu NAC61 gene function gene interaction
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Comparison of efficacy of lung ultrasound and chest X-ray in diagnosing pulmonary edema and pleural effusion in ICU patients: A single centre, prospective, observational study
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作者 Kunal Tewari Sumanth Pelluru +5 位作者 Deepak Mishra Nitin Pahuja Akash Ray Mohapatra Jyotsna Sharma Om Bahadur Thapa Manjot Multani 《Open Journal of Anesthesiology》 2024年第3期41-50,共10页
Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LU... Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LUS) in resource-rich ICUs is still under investigation. The present study compares the utility of LUS to that of CXR in identifying pulmonary edema and pleural effusion in ICU patients. In addition, consolidation and pneumothorax were analyzed as secondary outcome measures. Material and Methods This is a prospective, single centric, observational study. Patients admitted in ICU were examined for lung pathologies, using LUS by a trained intensivist;and CXR done within 4 hours of each other. The final diagnosis was ascertained by an independent senior radiologist, based on the complete medical chart including clinical findings and the results of thoracic CT, if available. The results were compared and analyzed. Results Sensitivity, specificity and diagnostic accuracy of LUS was 95%, 94.4%, 94.67% for pleural effusion;and 98.33%, 97.78%, 98.00% for pulmonary edema respectively. Corresponding values with CXR were 48.33%, 76.67%, 65.33% for pleural effusion;and 36.67%, 82.22% and 64.00% for pulmonary edema respectively. Sensitivity, specificity and diagnostic accuracy of LUS was 91.30%, 96.85%, 96.00% for consolidation;and 100.00%, 79.02%, 80.00% for pneumothorax respectively. Corresponding values with CXR were 60.87%, 81.10%, 78.00% for consolidation;and 71.3%, 97.20%, 96.00% for pneumothorax respectively. Conclusion LUS has better diagnostic accuracy in diagnosis of pleural effusion and pulmonary edema when compared with CXR and is thus recommended as an effective alternative for diagnosis of these conditions in acute care settings. Our study recommends that a thoracic CT scan can be avoided in most of such cases. 展开更多
关键词 Chest X ray (CXR) CONSOLIDATION Pulmonary edema Pleural effusion lung ultrasound (luS) PNEUMOTHORAX
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皖南伏岭A型花岗岩的成因——地球化学、锆石U-Pb年龄及Lu—Hf同位素特征
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作者 郑伟 陈天虎 +3 位作者 杜建国 陈芳 丁宁 张舒 《地质论评》 CAS CSCD 北大核心 2024年第1期189-206,共18页
伏岭花岗岩体,位于江南造山带东段的皖浙相邻区,岩浆岩沿着近北东向的宁国—绩溪深大断裂断分布。笔者等对伏岭岩体鱼龙川(γ_(5)^(3-2))单元花岗岩开展了系统的全岩岩石地球化学、LA-ICPMS锆石U-Pb同位素年龄和锆石原位Lu—Hf同位素地... 伏岭花岗岩体,位于江南造山带东段的皖浙相邻区,岩浆岩沿着近北东向的宁国—绩溪深大断裂断分布。笔者等对伏岭岩体鱼龙川(γ_(5)^(3-2))单元花岗岩开展了系统的全岩岩石地球化学、LA-ICPMS锆石U-Pb同位素年龄和锆石原位Lu—Hf同位素地球化学研究,结果表明,花岗岩的侵位年龄为131.8±0.9 Ma,富硅、富碱、贫钙、贫铁,具有较高的Rb、Th、U、Ga、Zr和Y含量,较低的Sr、Ba和Nb含量,稀土配分曲线呈现典型的“海鸥式”分布特征,显示强烈的负Eu异常;微量元素原始地幔标准化蛛网图显示明显的Ba、Sr、Nb的负异常。其高SiO_(2)含量和Rb/Sr值、低Ba、Sr含量具备江南造山带东段皖南地区A型花岗岩的典型特征。岩体具有同源岩浆演化特征,源区可能存在磷灰石、钛铁矿的分离结晶作用,而辉石类的分离较少。伏岭岩体主要来源于地壳中镁铁质岩石的部分熔融,其地球化学特征继承于源岩。锆石ε_(Hf)(t)变化范围较小,均在-7.0~-4.6之间,二阶段模式年龄(TDM2)为1478~1630 Ma,伏岭花岗岩可能由中元古代古老下地壳部分熔融形成。伏岭岩体的形成可能受到碰撞作用的影响,岩体形成于后碰撞期,中元古代的基底岩石被大范围的熔融,从而产生了伏岭A型花岗岩。 展开更多
关键词 伏岭 A型花岗岩 岩石地球化学 锆石U-PB年龄 lu—Hf同位素 构造环境 江南造山带 皖南
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国产无载体镥[^(177)Lu]的制备及标记DOTA⁃TOC在神经内分泌肿瘤中的初步临床应用探讨
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作者 姚晓晨 张朋俊 +4 位作者 陈正国 杨宇川 田瑞 俞飞 王峰 《南京医科大学学报(自然科学版)》 CAS 北大核心 2024年第2期235-241,共7页
目的:阐述国产无载体镥[^(177)Lu]制备工艺及^(177)Lu标记1,4,7,10⁃四氮杂环十二烷⁃1,4,7,10⁃四乙酸⁃酪氨酸3⁃奥曲肽(1,4,7,10⁃tetraazacyclododecane⁃1,4,7,10⁃tetraacetic acid conjugated Tyr3⁃octreotide,DOTA⁃TOC)的方法,探讨国产^... 目的:阐述国产无载体镥[^(177)Lu]制备工艺及^(177)Lu标记1,4,7,10⁃四氮杂环十二烷⁃1,4,7,10⁃四乙酸⁃酪氨酸3⁃奥曲肽(1,4,7,10⁃tetraazacyclododecane⁃1,4,7,10⁃tetraacetic acid conjugated Tyr3⁃octreotide,DOTA⁃TOC)的方法,探讨国产^(177)Lu⁃DO⁃TA⁃TOC初步临床应用的安全性及有效性。方法:采用多级连续分离纯化制备国产无载体镥[^(177)Lu],全自动化模块标记合成^(177)Lu⁃DOTA⁃TOC,回顾分析南京医科大学附属南京医院4例仅接受了国产无载体镥[^(177)Lu]标记DOTA⁃TOC的肽受体放射性核素靶向治疗(peptide receptor radionuclide therapy,PRRT)神经内分泌肿瘤(neuroendocrine neoplasm,NEN)患者资料。结果:国产无载体镥[^(177)Lu]质控良好,铜<0.01,锌<0.01,铁<0.01,铅<0.15,镱未检出,放化纯>99%,细菌内毒素<2 EU/mL。国产^(177)Lu⁃DOTA⁃TOC自动化标记产率为(98.85±0.97)%,产品比活度为(80.96±7.47)GBq/μmol,无菌和内毒素检测均符合规定标准,标记产物中乙醇含量为0,放化纯大于99%。仅接受国产^(177)Lu⁃DOTA⁃TOC治疗的4例患者中,1例仅1次治疗后原发灶及转移灶几乎完全消失,1例治疗后1个月出现3级骨髓毒性,治疗后3个月恢复至正常,所有患者均未出现肾毒性。结论:国产无载体镥[^(177)Lu]标记DOTA⁃TOC质控合格,产率高,安全、耐受性好,对于无法手术切除的NEN患者具有较好疗效。无载体镥[^(177)Lu]的国产化和批量化生产将推动我国核医学诊疗一体化的发展。 展开更多
关键词 无载体镥[^(177)lu] 神经内分泌肿瘤 肽受体放射性核素治疗 临床应用
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基于LU分解的安全外包求解线性代数方程组方法
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作者 冯达 周福才 +1 位作者 吴淇毓 李鲍 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期457-463,506,共8页
由于现有协议的安全性为基于某种安全假设的计算安全,依赖于敌手的计算能力,因此,本文针对恶意敌手模型,使用矩阵伪装技术对方程的系数矩阵进行隐藏,结合矩阵的LU分解(lower-upper decomposition)算法,提出一种新的信息论安全外包求解... 由于现有协议的安全性为基于某种安全假设的计算安全,依赖于敌手的计算能力,因此,本文针对恶意敌手模型,使用矩阵伪装技术对方程的系数矩阵进行隐藏,结合矩阵的LU分解(lower-upper decomposition)算法,提出一种新的信息论安全外包求解线性代数方程组(information-theoretically secure outsourcing of linear algebraic equations,ITS-OutsLAE)方法 .与之前的研究相比,在保持计算和通信复杂度与现有最优方案保持一致的同时,首次将方程组唯一解的安全性提升至信息论安全(完美保密).给出了形式化的安全性证明,并通过理论分析和实验证明了所提方法的实用性. 展开更多
关键词 线性代数方程组 信息论安全 安全外包 lu分解 恶意敌手模型
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燕辽裂陷槽基底陆壳生长事件——来自长城系碎屑锆石U-Pb年龄和Lu—Hf同位素的启示
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作者 李文奇 刘汇川 +3 位作者 刘小平 于志琪 王艺壬 王莹莹 《地质论评》 CAS CSCD 北大核心 2024年第4期1335-1352,共18页
华北克拉通大陆地壳生长已有大量研究,但对于被巨厚沉积盖层覆盖的燕辽裂陷槽基底地壳生长的问题前人讨论较少。笔者等以燕辽裂陷槽基底之上的长城系沉积岩为研究对象,统计了燕辽裂陷槽内长城系地层中碎屑锆石年龄频谱和Lu—Hf同位素数... 华北克拉通大陆地壳生长已有大量研究,但对于被巨厚沉积盖层覆盖的燕辽裂陷槽基底地壳生长的问题前人讨论较少。笔者等以燕辽裂陷槽基底之上的长城系沉积岩为研究对象,统计了燕辽裂陷槽内长城系地层中碎屑锆石年龄频谱和Lu—Hf同位素数据,探讨长城系地层沉积年龄、碎屑锆石沉积源区和地壳生长事件等科学问题。同位素年龄将燕辽裂陷槽长城系沉积年龄约束为1680 Ma,代表着燕辽裂陷槽的开启时间。燕辽裂陷槽长城系碎屑锆石年龄频谱主要显示为2.7~2.5 Ga和2.2~1.9 Ga两个阶段,Hf同位素ε_(Hf)(t)表现为高的正值区间0.1~34.6。通过对比长城系碎屑锆石与华北克拉通结晶基底的U-Pb定年、Lu—Hf同位素ε_(Hf)(t)和T_(DM2)模式年龄数据,推测燕辽裂陷槽长城系沉积物源为燕辽裂陷槽下伏基底。结合碎屑锆石U-Pb定年、ε_(Hf)(t)值和T_(DM2)模式年龄数据,我们认为燕辽裂陷槽下伏基底中元古代前地壳生长有3个峰值,分别为2.7~2.5 Ga,2.2~1.9 Ga和1.7~1.6 Ga。 展开更多
关键词 燕辽裂陷槽 长城系 长城群 碎屑锆石 U-Pb年龄 lu—Hf同位素 陆壳生长
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基于鲲鹏处理器的LU并行分解优化算法
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作者 徐鹤 周涛 +2 位作者 李鹏 秦芳芳 季一木 《计算机科学》 CSCD 北大核心 2024年第9期51-58,共8页
ScaLAPACK(Scalable Linear Algebra PACKage)是并行计算软件包,适用于分布式存储的MIMD(Multiple Instruction,Multiple Data)并行计算机,被广泛应用于基于线性代数运算的并行应用程序开发。然而在进行LU分解过程中,ScaLAPACK库中的例... ScaLAPACK(Scalable Linear Algebra PACKage)是并行计算软件包,适用于分布式存储的MIMD(Multiple Instruction,Multiple Data)并行计算机,被广泛应用于基于线性代数运算的并行应用程序开发。然而在进行LU分解过程中,ScaLAPACK库中的例程并不是通信最优的,没有充分利用当前的并行架构。针对上述问题,提出一种基于鲲鹏处理器的LU并行分解优化算法(Parallel LU Factorization,PLF),实现了负载均衡,适配国产鲲鹏环境。PLF对不同进程的不同分区的数据进行差异化处理,并将每个进程所拥有的部分数据分配给根进程进行计算,之后再由根进程散播回各个子进程,这有利于充分利用CPU资源,实现负载均衡。在单节点Intel 9320R处理器以及鲲鹏(Kunpeng)920处理器环境中进行测试,其中,Intel平台下使用Intel MKL(Math Kernel Library),Kunpeng平台下使用PLF算法。对比两个平台关于不同规模的方程组求解的性能发现,Kunpeng平台的求解性能有显著优势。在NUMA数进程和单线程的情况下,优化后的计算效率在小规模平均达到4.35%,相比Intel的1.38%提升了215%;中规模平均达到4.24%,相比Intel平台的1.86%提升了118%;大规模平均达到4.24%,相比Intel的1.99%提升了113%。 展开更多
关键词 SCALAPACK lu分解 并行计算 MKL
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A Survey of English Translation Studies of Lu You’s Poetry Based on the Data Analysis of Domestic Academic Journals (2001-2022)
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作者 Dongfang Chen Jiesen Ma 《Open Journal of Applied Sciences》 2023年第6期847-857,共11页
This article presents a comprehensive analysis of the current state of research on the English translation of Lu You’s poetry, utilizing a data sample comprising research papers published in the CNKI Full-text Databa... This article presents a comprehensive analysis of the current state of research on the English translation of Lu You’s poetry, utilizing a data sample comprising research papers published in the CNKI Full-text Database from 2001 to 2022. Employing rigorous longitudinal statistical methods, the study examines the progress achieved over the past two decades. Notably, domestic researchers have displayed considerable interest in the study of Lu You’s English translation works since 2001. The research on the English translation of Lu You’s poetry reveals a diverse range of perspectives, indicating a rich body of scholarship. However, several challenges persist, including insufficient research, limited translation coverage, and a noticeable focus on specific poems such as “Phoenix Hairpin” in the realm of English translation research. Consequently, there is ample room for improvement in the quality of research output on the English translation of Lu You’s poems, as well as its recognition within the academic community. Building on these findings, it is argued that future investigations pertaining to the English translation of Lu You’s poetry should transcend the boundaries of textual analysis and encompass broader theoretical perspectives and research methodologies. By undertaking this shift, scholars will develop a more profound comprehension of Lu You’s poetic works and make substantive contributions to the field of translation studies. Thus, this article aims to bridge the gap between past research endeavors and future possibilities, serving as a guide and inspiration for scholars to embark on a more nuanced and enriching exploration of Lu You’s poetry as well as other Chinese literature classics. 展开更多
关键词 lu You’s Poetry English Translation Studies Data analysis Translation Criticism
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氢溴酸伏硫西汀片杂质Lu AF39904的合成
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作者 曹雪丽 郭晓 王建强 《化学研究与应用》 CAS 北大核心 2024年第8期1956-1960,共5页
本文报道了氢溴酸伏硫西汀片杂质Lu AF39904的合成方法。以2-溴碘苯、2,4-二甲基苯硫酚和哌嗪为原料,经“一锅法”反应制得氢溴酸伏硫西汀,氢溴酸伏硫西汀碱化游离后与溴乙酰氯缩合经一步反应即可制得杂质Lu AF39904。杂质Lu AF39904的... 本文报道了氢溴酸伏硫西汀片杂质Lu AF39904的合成方法。以2-溴碘苯、2,4-二甲基苯硫酚和哌嗪为原料,经“一锅法”反应制得氢溴酸伏硫西汀,氢溴酸伏硫西汀碱化游离后与溴乙酰氯缩合经一步反应即可制得杂质Lu AF39904。杂质Lu AF39904的结构经^(1)H-NMR、^(13)C-NMR和HR-MS(ESI)确证。该合成路线反应条件温和、原料廉价易得、操作简便。合成的杂质Lu AF39904为氢溴酸伏硫西汀片的质量控制提供了标准对照品。 展开更多
关键词 氢溴酸伏硫西汀 lu AF39904 合成
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The Reading Movement in Shanghai,China in the Late 1950s
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作者 LIU Hao JING Huilan 《International Relations and Diplomacy》 2024年第2期86-90,共5页
At the end of the 1950s,Shanghai region of China carried out the Lu Xun Medal Reading Campaign and the Red Flag Reading Campaign one after another,aiming to guide young people to read good books and cultivate a positi... At the end of the 1950s,Shanghai region of China carried out the Lu Xun Medal Reading Campaign and the Red Flag Reading Campaign one after another,aiming to guide young people to read good books and cultivate a positive interest in life through reading,which is a gentle and constant form of ideological education.Based on the historical materials collected by Shanghai Archives,the author investigated the background,development,main links,and effects of the reading movement.The research shows that the reading movement has promoted young peoples political awareness,broadened their knowledge horizons,and promoted the formation of a good social atmosphere. 展开更多
关键词 lu Xun Medal Reading Campaign Red Flag Reading Campaign YOUTH ideological education
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Lu_(2)O_(3):Yb,Tm/MC540纳米材料的制备及研究
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作者 王国薇 韩丽君 +2 位作者 潘思文 张洪光 张英博 《当代化工研究》 CAS 2024年第3期179-181,共3页
以水热反应及后续的高温煅烧过程为合成手段,成功制备了Lu_(2)O_(3):Yb,Tm纳米材料。XRD结果显示所得样品为纯Lu2O3晶相。且SEM结果表明所得样品由不规则形状组成,粒径在100nm左右。随后通过搅拌吸附过程负载部花青(MC540)光敏剂,得到Lu... 以水热反应及后续的高温煅烧过程为合成手段,成功制备了Lu_(2)O_(3):Yb,Tm纳米材料。XRD结果显示所得样品为纯Lu2O3晶相。且SEM结果表明所得样品由不规则形状组成,粒径在100nm左右。随后通过搅拌吸附过程负载部花青(MC540)光敏剂,得到Lu_(2)O_(3):Yb,Tm/MC540纳米材料。然后以肺癌细胞(A-549细胞)为模型,研究了Lu_(2)O_(3):Yb,Tm/MC540纳米材料的抗肿瘤活性。结果表明,在650nm的红光照射下,上述材料对肺癌A-549细胞具有明显的光动力杀伤疗效。 展开更多
关键词 lu2O3:Yb Tm MC540光敏剂 光动力 抗肿瘤活性
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基于Lu模型的土石坝温度场对坝体渗流场的响应分析
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作者 唐友山 《陕西水利》 2024年第1期4-7,共4页
研究温度场与渗流场相互影响特征对土石坝渗流热监测具有重大意义。以均质土石坝为研究对象,采用COMSOL Multiphysics软件自带的多孔介质传热模块和多孔介质地下水渗流模块进行计算,模型中引入Lu模型来描述导热系数与含水量的定量关系,... 研究温度场与渗流场相互影响特征对土石坝渗流热监测具有重大意义。以均质土石坝为研究对象,采用COMSOL Multiphysics软件自带的多孔介质传热模块和多孔介质地下水渗流模块进行计算,模型中引入Lu模型来描述导热系数与含水量的定量关系,同时考虑流体温变效应,建立二维均质多孔介质饱和-非饱和渗流传热模型。结果表明,土体饱和度对坝体传热影响较大,非饱和土中,导热系数最大值与最小值相差可达50%以上,导热系数随土体饱和度的增大而增大,与传统热参数模型相比,Lu模型能够更好地刻画土体饱和度与热参数的关系。坝体温度场对渗流场变化敏感,可以通过温度场来反馈坝体渗漏。 展开更多
关键词 温度场 饱和非饱和渗流场 耦合 lu模型
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神经肽类似物DOTA-Substance P的^(177)Lu标记及其生物分布 被引量:4
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作者 梁积新 李洪玉 +6 位作者 向学琴 罗洪义 胡连生 邓新荣 陈阳 庄玲 罗志福 《同位素》 CAS 2012年第2期65-70,共6页
为探讨神经肽类药物177 Lu-DOTA-Substance P(以下简称为177 Lu-DOTA-SP)用于人胰腺癌PANC-1的肿瘤显像及治疗的可能性,研究了DOTA-SP的177 Lu标记;考察了177 Lu-DOTA-SP在室温下生理盐水中与在37℃小牛血清中的稳定性;评价了177 Lu-DOT... 为探讨神经肽类药物177 Lu-DOTA-Substance P(以下简称为177 Lu-DOTA-SP)用于人胰腺癌PANC-1的肿瘤显像及治疗的可能性,研究了DOTA-SP的177 Lu标记;考察了177 Lu-DOTA-SP在室温下生理盐水中与在37℃小牛血清中的稳定性;评价了177 Lu-DOTA-SP在正常昆明小鼠与人胰腺癌PANC-1模型裸鼠体内的生物分布特点,并对人胰腺癌PANC-1模型裸鼠进行了SPECT显像研究。结果表明,在优化条件下,DOTA-SP的177 Lu标记率>90%,纯化后,177 Lu-DOTA-SP的放化纯度>98%。177 Lu-DOTA-SP在生理盐水与5%小牛血清中显示了良好的稳定性,与浓度较高的血清(10%)竞争反应时,其降解稍快。177 Lu-DOTA-SP在正常昆明小白鼠体内的生物分布特点为:血清除快,肾放射性摄取高且滞留时间长;骨中有一定放射性摄取,且滞留长。177 Lu-DOTA-SP在人胰腺癌PANC-1模型裸鼠中的体内分布结果表明,肿瘤细胞中放射性摄取在给药后不同时间点均高于正常胰腺细胞中的放射性摄取,提示在PANC-1肿瘤细胞中有NK-1受体存在。SPECT显像结果显示,177 Lu-DOTA-SP在肿瘤细胞中放射性浓集并不明显。177 Lu-DOTA-SP应用于胰腺癌肿瘤显像与治疗的价值尚需进一步研究。 展开更多
关键词 DOTA-SubstanceP 177lu标记 生物分布
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Synthesis and upconversion luminescence of Lu_2O_3:Yb^(3+),Tm^(3+) nanocrystals 被引量:5
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作者 李丽 曹雪琴 +1 位作者 张友 郭常新 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期373-379,共7页
Lutetium oxide nanocrystals codoped with Tm3+ and Yb3+ were synthesized by the reverse-like co-precipitation method, using ammonium hydrogen carbonate as precipitant. Effects of the Tm3+, Yb3+ molar fractions and ... Lutetium oxide nanocrystals codoped with Tm3+ and Yb3+ were synthesized by the reverse-like co-precipitation method, using ammonium hydrogen carbonate as precipitant. Effects of the Tm3+, Yb3+ molar fractions and calcination temperature on the structural and upconversion luminescent properties of the Lu2O3 nanocrystals were investigated. The XRD results show that all the prepared nanocrystals can be readily indexed to pure cubic phase of Lu2O3 and indicate good crystallinity. The experimental results show that concentration quenching occurs when the mole fraction of Tm3+ is above 0.2%. The optimal Tm3+ and Yb3+ doped molar fractions are 0.2% and 2%, respectively. The strong blue (490 nm) and the weak red (653 nm) emissions from the prepared nanocrystals were observed under 980 nm laser excitation, and attributed to the 1G4→3H6 and IG4→3F4 transitions of Tm3+, respectively. Power-dependent study reveals that the 1G4 levels of Tm3+ can be populated by three-step energy transfer process. The upconversion emission intensities of 490 nm and 653 nm increase gradually with the increase of calcination temperature. The enhancement of the upconversion luminescence is suggested to be the consequence of reducing number of OH- groups and the enlarged nanoerystal size. 展开更多
关键词 lu2O3:yb3+ Tm3+nanocrystal co-precipitation method upconversion luminescence
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贡山三尖杉的新名称(Cephalotaxus talonensis Cheng et Feng ex S.G.Lu et X.D.Lang)及分类地位(英文) 被引量:1
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作者 郎学东 苏建荣 陆树刚 《植物研究》 CAS CSCD 北大核心 2013年第1期4-6,共3页
提议贡山三尖杉的新名称Cephalotaxus talonensis Cheng et Feng ex S.G.Lu et X.D.Lang替代不合法的旧名称Cephalotaxus lanceolata K.M.Feng in Cheng et al.(晚出同名)。对比贡山三尖杉和三尖杉Cephalotaxus fortunei Hooker的模式... 提议贡山三尖杉的新名称Cephalotaxus talonensis Cheng et Feng ex S.G.Lu et X.D.Lang替代不合法的旧名称Cephalotaxus lanceolata K.M.Feng in Cheng et al.(晚出同名)。对比贡山三尖杉和三尖杉Cephalotaxus fortunei Hooker的模式标本和自然生长状态下的叶片形态,支持将贡山三尖杉处理为种的等级,不赞同Silba(1990)将贡山三尖杉降为三尖杉的变种[Cephalotaxus fortunei Hooker var.lanceolata(Feng)Silba]。文中提供4幅参照图片。 展开更多
关键词 三尖杉科 Cephalotaxus talonensis Cheng ET Feng EX S G lu ET X D Lang 新名称
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广义Vandermonde矩阵及其LU分解 被引量:1
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作者 杨胜良 《兰州理工大学学报》 CAS 北大核心 2004年第1期116-119,共4页
利用对称函数引入了两种广义Vandermonde矩阵,讨论了Vandermonde矩阵与广义Vandermonde矩阵之间的关系,并得到了广义Vandermonde矩阵的LU分解.
关键词 广义VanDERMONDE矩阵 lu分解 初等对称函数 完全对称函数
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高亮度固态照明用LuYAG∶Ce荧光陶瓷 被引量:2
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作者 黄新友 王雁斌 +7 位作者 程梓秋 陈昊鸿 代正发 田丰 陈鹏辉 胡松 周国红 李江 《发光学报》 EI CAS CSCD 北大核心 2023年第6期964-974,共11页
实现高发光效率、高亮度和良好的热稳定性是固态照明的迫切要求。因此,用于高功率发光二极管或激光二极管(LED/LD)的高性能荧光转换材料具有重要的研究意义。在这项工作中,通过将Lu^(3+)离子引入YAG∶Ce荧光陶瓷中方法作为有效策略来改... 实现高发光效率、高亮度和良好的热稳定性是固态照明的迫切要求。因此,用于高功率发光二极管或激光二极管(LED/LD)的高性能荧光转换材料具有重要的研究意义。在这项工作中,通过将Lu^(3+)离子引入YAG∶Ce荧光陶瓷中方法作为有效策略来改善YAG∶Ce荧光材料的发光性能。采用固相反应和真空烧结法制Article ID:1000-7032(2023)06-0964^(-1)1收稿日期:2022^(-1)2-31;修订日期:2023-01-30基金项目:中国科学院战略性先导科技专项(XDA22010301)Supported by The Strategic Priority Research Program of The Chinese Academy of Sciences(XDA22010301)第6 HUANG Xinyou期,et al.:LuYAG∶Ce Transparent Ceramic Phosphors for High-brightness Solid-state…备了不同Lu^(3+)含量的(Lu,Y)_(3)Al_(5)O_(12)∶Ce荧光陶瓷(LuYAG∶Ce荧光陶瓷)。随着Lu^(3+)含量的增加,LuYAG∶Ce荧光陶瓷中的Y^(3+)位点被Lu^(3+)位点取代,Ce^(3+)的发射峰呈现从573 nm到563 nm的蓝移现象。当Lu^(3+)含量为60%时,通过将LuYAG∶Ce荧光陶瓷与蓝光LED组合,其发光强度达到最大值,流明效率达到114 lm∙W^(-1)。使用450 nm激光源与LuYAG∶Ce荧光陶瓷构建了透射模式下的激光驱动照明装置。随着功率密度从2.2 W·mm^(-2)增加到39 W·mm^(-2),Lu^(3+)含量为60%的荧光陶瓷光通量从128 lm增加到1874 lm,且没有发光饱和的迹象,最佳发光效率达到128 lm·W^(-1)。因此,LuYAG∶Ce荧光陶瓷有望成为高功率LED/LD照明的潜在荧光转换材料。 展开更多
关键词 (lu Y)_(3)Al_(5)O_(12)∶Ce荧光陶瓷 固态照明 荧光转换材料 高亮度
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合流多项式Vandermonde矩阵的块LU分解
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作者 吴越 《佳木斯大学学报(自然科学版)》 CAS 2015年第6期824-826,共3页
将给出多项式基下合流Vandermonde矩阵的块LU分解,它是基于多项式基下合流Vandermonde矩阵所满足的位移结构方程这一特殊形式,利用这一特殊形式对多项式合流Vandermonde矩阵进行Gauss消元法,从而降低算法的运算量.在降低运算量的基础上... 将给出多项式基下合流Vandermonde矩阵的块LU分解,它是基于多项式基下合流Vandermonde矩阵所满足的位移结构方程这一特殊形式,利用这一特殊形式对多项式合流Vandermonde矩阵进行Gauss消元法,从而降低算法的运算量.在降低运算量的基础上,运用位移结构矩阵Schur补的性质来计算此类矩阵的LU分解. 展开更多
关键词 位移结构 合流Vandermonde矩阵 SCHUR补 lu分解
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Road or Lu, Is It Still a Question?—On Translation of Road and Street Names from the Perspective of Functional Theories
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作者 贺婷婷 《海外英语》 2012年第16期140-141,158,共3页
The translation of road names from Chinese into English applies no specific standards up to date. Whether the roads should be re ferred in accordance with the nearby position or some symbolic buildings or simply be re... The translation of road names from Chinese into English applies no specific standards up to date. Whether the roads should be re ferred in accordance with the nearby position or some symbolic buildings or simply be represented by a phonetic pronunciation which has no specific meaning in English has provoked some heated discussion. In this paper I employ the skopos theory and other relevant theories to put forward a new perspective of translating road and street names, with same emphasis on that of generic name and on specific name. Some illustrations will be made on the defects of the writing standard set by relevant Chinese laws and regulations as well as resolutions of the United Nations Conference on the Standardization of Geographical Names, i.e. the adoption of a Single Romanization System, and Lu to be the generic name in China's case. Also, I will further probe the existing translations of road and street names in major Chinese cities, most of which to be Road, either go against relevant laws or fail to inform foreign visitors. Finally, I will come up with the suggestion of ap plication of a combination of Lu and Road in translation of road and street names in accordance with functional approaches. 展开更多
关键词 ROAD lu TRanSLATION of ROAD and STREET NAMES
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Preconditioned BiCGSTAB algorithm and its applications to eddy current solutions 被引量:1
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作者 朱发熙 余海涛 胡敏强 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期362-366,共5页
A new favorable iterative algorithm named as PBiCGSTAB (preconditioned bi-conjugate gradient stabilized) algorithm is presented for solving large sparse complex systems. Based on the orthogonal list, the special tec... A new favorable iterative algorithm named as PBiCGSTAB (preconditioned bi-conjugate gradient stabilized) algorithm is presented for solving large sparse complex systems. Based on the orthogonal list, the special technique of only storing non-zero elements is carried out. The incomplete LU factorization without fill-ins is adopted to reduce the condition number of the coefficient matrix. The BiCGSTAB algorithm is extended from the real system to the complex system and it is used to solve the preconditioned complex linear equations. The locked-rotor state of a single-sided linear induction machine is simulated by the software programmed with the finite element method and the PBiCGSTAB algorithm. Then the results are compared with those from the commercial software ANSYS, showing the validation of the proposed software. The iterative steps required for the proposed algorithm are reduced to about one-third, when compared to the BiCG method, therefore the algorithm is fast. 展开更多
关键词 preconditioned bi-conjugate gradient stabilized BiCGSTAB algorithm incomplete lu decomposition orthogonal list finite dement method(FEM) eddy current
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