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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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^(177)Lu-前列腺特异性膜抗原放射性配体疗法治疗前列腺癌临床应用专家共识
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作者 刘国兵 卓维海 +43 位作者 顾宇参 杨志 陈跃 樊卫 郭剑明 谭建 朱小华 霍力 兰晓莉 李彪 缪蔚冰 宋少莉 徐浩 田蓉 罗全勇 王峰 王雪梅 杨爱民 戴东 邓智勇 赵晋华 陈晓良 范岩 高再荣 韩星敏 蒋宁一 匡安仁 林岩松 刘甫庚 楼岑 苏新辉 唐立钧 王辉 王欣璐 杨福洲 杨辉 赵新明 杨波 黄晓冬 陈继亮 李思进 汪静 李亚明 石洪成 《中国临床医学》 2024年第5期844-850,F0003,共8页
^(177)Lu标记的前列腺特异性膜抗原(prostate specific membrane antigen,PSMA)放射性配体疗法已在国外获批应用于晚期前列腺癌治疗,且正在国内开展多项临床试验。专家组参考国外经验和观点,并结合国内临床实践和实测数据,形成^(177)Lu-... ^(177)Lu标记的前列腺特异性膜抗原(prostate specific membrane antigen,PSMA)放射性配体疗法已在国外获批应用于晚期前列腺癌治疗,且正在国内开展多项临床试验。专家组参考国外经验和观点,并结合国内临床实践和实测数据,形成^(177)Lu-PSMA放射性配体疗法在前列腺癌临床应用中的专家共识。 展开更多
关键词 ^(177)lu标记的前列腺特异性膜抗原 前列腺癌 放射性配体治疗 专家共识
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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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^(177)Lu-PSMA放射性配体疗法治疗前列腺癌的临床实践专家共识(2024年版) 被引量:1
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作者 中国抗癌协会肿瘤核医学专业委员会 中国医师协会核医学医师分会 +5 位作者 宋少莉 樊卫 黄钢 徐文贵 赵新明 杨辉 《中国癌症杂志》 CAS CSCD 北大核心 2024年第7期702-714,共13页
镥-177标记前列腺特异性膜抗原放射性配体疗法(^(177)Lu-labeled prostate-specific membrane antigen radioligand therapy,^(177)Lu-PSMA-RLT)是一种通过精准地向前列腺癌细胞递送^(177)Lu释放的β射线,引发肿瘤细胞DNA的辐射损伤从... 镥-177标记前列腺特异性膜抗原放射性配体疗法(^(177)Lu-labeled prostate-specific membrane antigen radioligand therapy,^(177)Lu-PSMA-RLT)是一种通过精准地向前列腺癌细胞递送^(177)Lu释放的β射线,引发肿瘤细胞DNA的辐射损伤从而杀灭肿瘤的创新治疗方法。现阶段国内外多个前列腺癌领域权威指南与共识推荐其用于治疗转移性去势抵抗性前列腺癌(metastatic castrate-resistant prostate cancer,mCRPC),国内尚未见关于^(177)Lu-PSMA-RLT治疗前列腺癌的临床实践路径和用药规范的报道。本共识由中国抗癌协会肿瘤核医学专业委员会和中国医师协会核医学医师分会共同发起,结合现有的^(177)Lu-PSMA-RLT注册研究结果、真实世界数据及国内外放射性核素临床治疗经验,根据牛津循证医学中心临床证据推荐等级和证据级别来评价不同级别的证据,在适应证、患者筛选、用药不良反应、随访和辐射安全等方面给出推荐意见。本共识旨在为临床医师提供^(177)Lu-PSMA-RLT治疗前列腺癌的临床参考,为进一步制订行业相关指南奠定基础。 展开更多
关键词 镥-177标记前列腺特异性膜抗原放射性配体疗法 前列腺癌 临床实践 专家共识
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中国沙漠结皮蓝藻新记录属——结席藻属(Crustifilum,Coleofasciculales)及相近属的分类讨论
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作者 许叶伟 郭晓雨 +4 位作者 陈友信 李华 段明 虞功亮 乔之怡 《水生生物学报》 CAS CSCD 北大核心 2024年第9期1581-1591,共11页
为进一步推进现代蓝藻分类系统单系化发展,研究对从宁夏沙坡头的土壤结皮样本中分离纯化得到CHAB7530和CHAB7535两株丝状蓝藻进行了研究。该藻株在形态学上与束鞘丝藻类(Coleofasciculus-like)和微鞘藻类(Microcoleus-like)的物种相似,... 为进一步推进现代蓝藻分类系统单系化发展,研究对从宁夏沙坡头的土壤结皮样本中分离纯化得到CHAB7530和CHAB7535两株丝状蓝藻进行了研究。该藻株在形态学上与束鞘丝藻类(Coleofasciculus-like)和微鞘藻类(Microcoleus-like)的物种相似,基于16S rRNA基因的序列分析表明,CHAB7530和CHAB7535与帕斯结席藻(Crustifilum hispaliculae Moreira-Fernandes,Giraldo-Silva,D.Roush&Garcia-Pichel 2021)的序列相似性达99.7%—99.9%,系统发育分析表明它们与结席藻属(Crustifilum)聚集并形成支持度良好的进化分支。此外还补充了该物种的ITS二级结构数据。结合分子、形态学和生态学数据的多相方法分析表明CHAB7530和CHAB7535为帕斯结席藻(C.hispaliculae),该属种是中国新记录属种。文章还结合系统发育分析结果,对先前从Microcoleus steenstrupii复合体中独立出来的部分属(例Parifilum)进行了分类学的修改建议讨论。 展开更多
关键词 蓝藻 结席藻属 束鞘丝藻科 生物土壤结皮 沙漠 新记录属
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吉南夹皮沟地区变质侵入岩的锆石U-Pb定年、Lu-Hf同位素分析及其构造意义 被引量:1
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作者 徐强 郭佳丽 周喜文 《岩石学报》 SCIE EI CAS CSCD 北大核心 2024年第11期3363-3378,共16页
吉南夹皮沟变质地体作为华北克拉通东北部太古宙基底的重要组成部分,其新太古代到古元古代的构造演化过程一直存在争议。为此,在详细野外地质调查基础上,选择三种代表性变质侵入岩,开展了锆石稀土微量元素、锆石U-Pb定年与Lu-Hf同位素... 吉南夹皮沟变质地体作为华北克拉通东北部太古宙基底的重要组成部分,其新太古代到古元古代的构造演化过程一直存在争议。为此,在详细野外地质调查基础上,选择三种代表性变质侵入岩,开展了锆石稀土微量元素、锆石U-Pb定年与Lu-Hf同位素分析工作。结果显示:夹皮沟地区紫苏花岗岩的侵位年龄为2504±8Ma,并记录有2476±13Ma的变质年龄;其锆石Hf模式年龄介于2.82~2.66Ga之间,εHf(t)值介于1.72~5.1之间,反映为新生地壳物质再循环的产物。变辉长岩体(斜长角闪岩)的侵位年龄为2529±14Ma,并记录有2484±23Ma的变质年龄。变基性岩墙(石榴角闪岩)的侵位年龄为2214±18Ma,并记录有1930±16Ma的变质年龄;其岩浆锆石具有异常高的εHf(t)值(7~15),并存在明显的重稀土亏损现象,推测其母岩浆来源于富含石榴石的岩石圈地幔。综合多种信息,认为吉南地区新太古代末期(2.50~2.48Ga)构造热事件受大规模地幔柱活动控制,古元古代中晚期(2.2~1.84Ga)构造热事件可能源于克拉通边缘板块俯冲引起的碰撞造山作用。 展开更多
关键词 变质侵入体 锆石U-PB定年 锆石lu-Hf同位素 夹皮沟 吉林南部
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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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The influence of pressure waves in tidal gravity records
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作者 Bernard Ducarme 《Geodesy and Geodynamics》 CSCD 2023年第1期15-25,共11页
For the reduction of atmospheric effects,observed gravity has initially been corrected by using the computed barometric admittance k of the in situ measured pressure,expressed in nms-2/hPa units and estimated by least... For the reduction of atmospheric effects,observed gravity has initially been corrected by using the computed barometric admittance k of the in situ measured pressure,expressed in nms-2/hPa units and estimated by least squares method.However,the local pressure changes alone cannot account for the atmospheric mass attraction and loading when the coherent pressure field exceeds a specific size,i.e.,with increasing periodicities.To overcome this difficulty,it is necessary to compute the total atmospheric effect at each station using the global pressure field.However,the direct subtraction of the total gravity effect,provided by the models of pressure correction,is not yet satisfactory for S2 and other tidal components,such as K2 and P1,which include solar heating pressure tides.This paper identifies the origin of the problem and presents strategies to obtain a satisfactory solution.First,we set up a difference vector between the tidal factors of M2 and S2 after correction of the pressure and ocean tides effects.This vector,hereafter denoted as RES,presents the advantage of being practically insensitive to calibration errors.The minimum discrepancy between the tidal parameters of M2 and S2 corresponds to the minimum of the RES vector norm d.Secondly we adopt the hybrid pressure correction method,separating the local and the global pressure contribution of the models and replacing the local contribution by the pressure measured at the station multiplied by an admittance kATM.We tested this procedure on 8 stations from the IGETS superconducting gravimeters network(former GGP network).For stations at an altitude lower than 1000 m,the value of dopt is always smaller than0.0005.The discrepancy between the tidal parameters of the M2 and S2 waves is always lower than0.05% on the amplitude factors and 0.025° on the phases.For these stations,a correlation exists between the altitude and the value kopt.The results at the three Central European stations Conrad,Pecny and Vienna are in excellent agreement(0.05%) with the DDW99NH model for all the main tidal waves. 展开更多
关键词 Atmospheric pressure waves Atmospheric pressure correction in tidal records Atmospheric pressure models ERA5 and MERRA-2
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光柄菇属中国新记录种韦林加光柄菇(Pluteus vellingae)
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作者 张勇 王静怡 +2 位作者 李青 刘淑琴 王术荣 《北方园艺》 CAS 北大核心 2024年第9期117-123,共7页
以山西省野生大型真菌资源调查过程中采集到的2份光柄菇属真菌标本为试材,采用形态学鉴定方法,并基于rDNA ITS区采用贝叶斯法(bayesian inference,BI)和最大似然法(maximum likelihood,ML)系统发育树的构建,研究了其宏观、微观形态特征... 以山西省野生大型真菌资源调查过程中采集到的2份光柄菇属真菌标本为试材,采用形态学鉴定方法,并基于rDNA ITS区采用贝叶斯法(bayesian inference,BI)和最大似然法(maximum likelihood,ML)系统发育树的构建,研究了其宏观、微观形态特征和系统发育关系,以期对我国光柄菇属物种的种类及分布有所补充。结果表明:该物种的典型特征是子实体较小,菌盖黄棕色,菌肉白色,菌褶浅黄色,菌柄淡黄色至亮黄色,菌柄内部菌肉黄色,孢子球形、近球形或宽椭圆形,(5.8~7.5)μm×(5.1~6.3)μm,具有发达的缘囊体、侧囊体和柄囊体。该物种与模式物种韦林加光柄菇(Pluteus vellingae)的序列聚为一个分支,分子系统学研究结果高度支持形态学研究结果。结合形态学和系统发育分析,确定该物种为中国新记录种韦林加光柄菇(Pluteus vellingae),广泛分布在北半球的北美洲、欧洲和亚洲等地,属于北温带分布种。 展开更多
关键词 光柄菇属 鉴定 新记录 系统发育分析
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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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Lu-Mg和Lu-Al合金热力学性质的理论分析
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作者 纪凡 何荧 +1 位作者 向金秋 罗立平 《世界有色金属》 2024年第6期20-23,共4页
文章利用Miedema生成热模型计算Lu-Mg和Lu-Al二元合金的混合焓、过剩熵、过剩吉布斯自由能以及各组元的活度。结合Butler方程,计算Lu-Mg和Lu-Al合金熔体的表面张力以及表面相中各元素含量。研究结果表明,Lu-Mg和Lu-Al合金熔体的混合焓... 文章利用Miedema生成热模型计算Lu-Mg和Lu-Al二元合金的混合焓、过剩熵、过剩吉布斯自由能以及各组元的活度。结合Butler方程,计算Lu-Mg和Lu-Al合金熔体的表面张力以及表面相中各元素含量。研究结果表明,Lu-Mg和Lu-Al合金熔体的混合焓、过剩熵以及过剩吉布斯自由能都为负值,同时各组分活度较理想熔体有着一定负偏差,说明Lu与Mg和Al原子之间存在显著的相互作用力。Lu-Mg和Lu-Al合金熔体表面张力随Mg和Al含量的增加而减小,Mg和Al元素均会向熔体表面富集。 展开更多
关键词 MIEDEMA模型 Butler方程 活度 表面张力 lu-Mg lu-Al
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^(177)Lu-DOTATATE治疗GEP-NEN的体外辐射剂量学研究
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作者 戚鸣 张建平 +7 位作者 陈峙昊 杨洪星 乔莹 黄正文 唐亦睿 刘菲 徐俊彦 宋少莉 《肿瘤影像学》 2024年第5期501-507,共7页
目的:探讨^(177)Lu-DOTATATE治疗胃肠胰神经内分泌肿瘤(gastroenteropancreatic neuroendocrine neoplasm,GEP-NEN)后不同时间点患者体外辐射水平,为辐射安全及患者管理提供参考依据。方法:选择2023年5—11月在复旦大学附属肿瘤医院接受... 目的:探讨^(177)Lu-DOTATATE治疗胃肠胰神经内分泌肿瘤(gastroenteropancreatic neuroendocrine neoplasm,GEP-NEN)后不同时间点患者体外辐射水平,为辐射安全及患者管理提供参考依据。方法:选择2023年5—11月在复旦大学附属肿瘤医院接受^(177)Lu-DOTATATE住院治疗的GEP-NEN患者作为研究对象,单次静脉给予(7618.5±241.9)MBq的^(177)Lu-DOTATATE治疗,在给药后不同时间点,测量其正前方1 m处的周围剂量当量率,分析周围剂量当量率随时间的变化规律。结果:纳入的30例GEP-NEN患者共行78次^(177)Lu-DOTATATE治疗,给药结束后即刻其正前1 m处的平均剂量当量率为20.0μSv/h。周围剂量当量率随时间呈指数衰减,其降至10μSv/h的平均时间为3.95 h,95%CI上限时间为4.6 h。24 h内周围剂量当量率的有效半衰期为1.42 h。结论:在每次^(177)Lu-DOTATATE治疗后,其周围剂量当量率随时间快速降低,平均3.95 h时其在1 m处的周围剂量当量率降至10μSv/h。在4.6 h时,95%的患者可降至10μSv/h以下。本研究为中国制定^(177)Lu-DOTATATE治疗时患者的出院标准或患者的管理提供试验数据和依据。 展开更多
关键词 ^(177)lu-DOTATATE 肽受体放射性核素治疗 周围剂量当量率 辐射剂量
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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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Three new records of lycopsids and ferns from Vietnam
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作者 LU Yu WANG Bo +2 位作者 LIN Guoliang JIANG Rihong WANG Zhenxing 《广西植物》 CAS CSCD 北大核心 2024年第10期1943-1946,共4页
Three new records from Vietnam,Phlegmariurus guangdongensis Ching,Adiantum longzhouensis A.H.Wang,F.G.Wang&F.W.Xing,and Lepisorus bicolor Ching,are reported.The identification characteristics,information of specim... Three new records from Vietnam,Phlegmariurus guangdongensis Ching,Adiantum longzhouensis A.H.Wang,F.G.Wang&F.W.Xing,and Lepisorus bicolor Ching,are reported.The identification characteristics,information of specimen,and geographical distribution of the species are described.The discovery of new records not only enriches the study of plant diversity in Vietnam,but also provides important information for biodiversity conservation and botanical research in the region.The voucher specimens are kept in the Herbarium of Kunming Institute of Botany,Chinese Academy of Sciences(KUN),Herbarium of Institute of Botany,Chinese Academy of Sciences(PE)and Herbarium of Guangxi Forestry Research Institute(GXFI). 展开更多
关键词 Phlegmariurus guangdongensis Adiantum longzhouensis Lepisorus bicolor new record VIETNAM
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An updated inventory of marine opisthobranch(Mollusca,Gastropoda)from the territorial waters of the Republic of Mauritius
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作者 Lisa AH SHEE TEE Chandani APPADOO +1 位作者 Daneshwar PUCHOOA Vishwakalyan BHOYROO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期226-243,共18页
Island ecosystems support diverse aquatic invertebrate communities comprising endemic taxa.Documentation of existing species is important for conservation.In this study,a checklist of marine opisthobranch from the Rep... Island ecosystems support diverse aquatic invertebrate communities comprising endemic taxa.Documentation of existing species is important for conservation.In this study,a checklist of marine opisthobranch from the Republic of Mauritius is presented.A combination of benthic surveys(50 m×5 m in triplicates),rover diving techniques and photo documentation were used over two years(2018–2020)within 35 sheltered and unsheltered lagoons.Morphological and molecular analysis were used for identification.Species composition within sheltered and unsheltered areas in Mauritius was estimated using the Bray-Curtis similarity.The checklist featured 117 species belonging to 61 genera and 28families,of which 13 are new records.The findings increased the knowledge of opisthobranch diversity from the Mauritius by 15.4%.Among the listed species,the distribution range of Cyerce nigra,Actinocyclus papillatus,and Phyllidia picta extended from the Western Pacific to the South Western Indian Ocean.Molecular analysis of the undescribed Gymnodoris sp.showed it resembled Gymnodoris sp.from Hawaii and were different by a genetic distance value of 10.6%.The species richness and evenness were higher within the sheltered regions of Mauritius which harboured the food resource of opisthobranch.These areas as compared to unsheltered regions were heavily populated,suggesting the probable influence of wave actions on opisthobranch diversity and abundance.The order Nudibranchia was reported as most speciose,with 86 species.The Sacoglossa and Nudibranchia were observed only on macroalgae and sponges respectively.High abundance was also recorded on shipwrecks which are the most common form of artificial reefs.With the inclusion of observations from previous studies,201species belonging to 94 genera and 36 families are now known from the Mauritius. 展开更多
关键词 marine opisthobranch INVENTORY new record occurrence Republic of Mauritius Indian Ocean
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Machine learning for carbonate formation drilling: Mud loss prediction using seismic attributes and mud loss records
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作者 Hui-Wen Pang Han-Qing Wang +4 位作者 Yi-Tian Xiao Yan Jin Yun-Hu Lu Yong-Dong Fan Zhen Nie 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1241-1256,共16页
Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production exp... Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production expenses. This research utilizes the H oilfield as an example, employs seismic features to analyze mud loss prediction, and produces a complete set of pre-drilling mud loss prediction solutions. Firstly, 16seismic attributes are calculated based on the post-stack seismic data, and the mud loss rate per unit footage is specified. The sample set is constructed by extracting each attribute from the seismic trace surrounding 15 typical wells, with a ratio of 8:2 between the training set and the test set. With the calibration results for mud loss rate per unit footage, the nonlinear mapping relationship between seismic attributes and mud loss rate per unit size is established using the mixed density network model.Then, the influence of the number of sub-Gausses and the uncertainty coefficient on the model's prediction is evaluated. Finally, the model is used in conjunction with downhole drilling conditions to assess the risk of mud loss in various layers and along the wellbore trajectory. The study demonstrates that the mean relative errors of the model for training data and test data are 6.9% and 7.5%, respectively, and that R2is 90% and 88%, respectively, for training data and test data. The accuracy and efficacy of mud loss prediction may be greatly enhanced by combining 16 seismic attributes with the mud loss rate per unit footage and applying machine learning methods. The mud loss prediction model based on the MDN model can not only predict the mud loss rate but also objectively evaluate the prediction based on the quality of the data and the model. 展开更多
关键词 Lost circulation Risk prediction Machine learning Seismic attributes Mud loss records
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Impact of Laboratory Value Flowsheet in Electronic Health Record (EHR) Documentation Time
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作者 Isabel Rosado Pogozelski 《Open Journal of Nursing》 2024年第1期40-50,共11页
Research on the use of EHR is contradictory since it presents contradicting results regarding the time spent documenting. There is research that supports the use of electronic records as a tool to speed documentation;... Research on the use of EHR is contradictory since it presents contradicting results regarding the time spent documenting. There is research that supports the use of electronic records as a tool to speed documentation;and research that found that it is time consuming. The purpose of this quantitative retrospective before-after project was to measure the impact of using the laboratory value flowsheet within the EHR on documentation time. The research question was: “Does the use of a laboratory value flowsheet in the EHR impact documentation time by primary care providers (PCPs)?” The theoretical framework utilized in this project was the Donabedian Model. The population in this research was the two PCPs in a small primary care clinic in the northwest of Puerto Rico. The sample was composed of all the encounters during the months of October 2019 and December 2019. The data was obtained through data mining and analyzed using SPSS 27. The evaluative outcome of this project is that there is a decrease in documentation time after implementation of the use of the laboratory value flowsheet in the EHR. However, patients per day increase therefore having an impact on the number of patients seen per day/week/month. The implications for clinical practice include the use of templates to improve workflow and documentation as well as decreasing documentation time while also increasing the number of patients seen per day. . 展开更多
关键词 Electronic Health Record EHR Laboratory Results Template Documentation Time
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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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