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冰盖流阻力与综合Manning糙率 被引量:25
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作者 魏良琰 黄继忠 《武汉大学学报(工学版)》 CAS CSCD 北大核心 2002年第4期1-8,共8页
给出了冰盖流分析的数学表述 ,考察了阻力项中的Manning糙率 .给出了完全封冻和不完全封冻冰盖流综合糙率的一般计算公式 .当冰盖比 f =1(完全封冻 )时化为Sabaneev公式 ,当 f =0 (完全明流 )时退化为床面糙率 .在长 32m、宽 0 .5m玻璃... 给出了冰盖流分析的数学表述 ,考察了阻力项中的Manning糙率 .给出了完全封冻和不完全封冻冰盖流综合糙率的一般计算公式 .当冰盖比 f =1(完全封冻 )时化为Sabaneev公式 ,当 f =0 (完全明流 )时退化为床面糙率 .在长 32m、宽 0 .5m玻璃水槽中进行了实验验证 .利用ADV测流技术实测流速剖面 ,分析壁面切应力流速和分区平均流速以率定不同的壁面糙率 . 展开更多
关键词 冰盖 河流阻力 manning糙率
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改良的Manning-Rosen势Schrdinger方程散射态解 被引量:2
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作者 陈文利 史艳维 鱼翔 《西华大学学报(自然科学版)》 CAS 2016年第4期39-43,47,共6页
对改良的Manning-Rosen势的径向薛定谔方程任意l波散射态进行解析求解,得到按"K/2π标度"的相移公式和归一化的超几何函数表示的径向波函数。通过对散射振幅在极点解析性质的研究得到束缚态能级,而特征值的数值结果与先前结... 对改良的Manning-Rosen势的径向薛定谔方程任意l波散射态进行解析求解,得到按"K/2π标度"的相移公式和归一化的超几何函数表示的径向波函数。通过对散射振幅在极点解析性质的研究得到束缚态能级,而特征值的数值结果与先前结果的比较进一步验证了本文结果的精确性。 展开更多
关键词 改良manning—Rosen势场 散射态 近似解析解
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肠易激综合征Manning诊断标准的评价
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作者 宗春华 李定国 +4 位作者 周惠清 宋光辉 刘清华 许小幸 陆汉明 《上海第二医科大学学报》 CSCD 2004年第2期117-119,共3页
目的 评价Manning标准诊断肠易激综合征(IBS)的真实性。方法 采用自行设计的调查表对499例对象进行调查。结果 1.随着Manning标准中结合指标数的增多,IBS组与非溃疡性消化不良及溃疡性结肠炎组鉴别的灵敏度及其95%CI明显下降,特异度及... 目的 评价Manning标准诊断肠易激综合征(IBS)的真实性。方法 采用自行设计的调查表对499例对象进行调查。结果 1.随着Manning标准中结合指标数的增多,IBS组与非溃疡性消化不良及溃疡性结肠炎组鉴别的灵敏度及其95%CI明显下降,特异度及其95%CI明显上升,同时阳性预测值、阳性似然比及阴性似然比也明显上升。2.符合Manning标准中二项以上结合指标,IBS组就具有较好与健康对照组鉴别的灵敏度及其95%CI.特异度及其95%CI。结论 Manning标准中需要3项以上结合指标可较好地使IBS与非溃疡性消化不良或溃疡性结肠炎鉴别;2项以上结合指标可较好地使IBS与健康人鉴别。 展开更多
关键词 肠易激综合征 manning诊断标准 评价 灵敏度 特异度
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Approximate solutions of Klein-Gordon equation with improved Manning-Rosen potential in D-dimensions using SUSYQM 被引量:3
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作者 A.N.Ikot H.Hassanabadi +3 位作者 H.P.Obong Y.E.Chad Umoren C.N.Isonguyo B.H.Yazarloo 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期38-43,共6页
In this paper, we present solutions of the Klein–Gordon equation for the improved Manning–Rosen potential for arbitrary l state in d-dimensions using the supersymmetric shape invariance method. We obtained the energ... In this paper, we present solutions of the Klein–Gordon equation for the improved Manning–Rosen potential for arbitrary l state in d-dimensions using the supersymmetric shape invariance method. We obtained the energy levels and the corresponding wave functions expressed in terms of Jacobi polynomial in a closed form for arbitrary l state. We also calculate the oscillator strength for the potential. 展开更多
关键词 Klein–Gordon equation improved manning–Rosen potential supersymmetric quantum mechanics(SUSYQM)
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Solution of Dirac equation for Eckart potential and trigonometric Manning Rosen potential using asymptotic iteration method 被引量:1
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作者 resita arum sari a suparmi c cari 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第1期428-435,共8页
The Dirac equation for Eckart potential and trigonometric Manning Rosen potential with exact spin symmetry is obtained using an asymptotic iteration method. The combination of the two potentials is substituted into th... The Dirac equation for Eckart potential and trigonometric Manning Rosen potential with exact spin symmetry is obtained using an asymptotic iteration method. The combination of the two potentials is substituted into the Dirac equation, then the variables are separated into radial and angular parts. The Dirac equation is solved by using an asymptotic iteration method that can reduce the second order differential equation into a differential equation with substitution variables of hypergeometry type. The relativistic energy is calculated using Matlab 2011. This study is limited to the case of spin symmetry. With the asymptotic iteration method, the energy spectra of the relativistic equations and equations of orbital quantum number l can be obtained, where both are interrelated between quantum numbers. The energy spectrum is also numerically solved using the Matlab software, where the increase in the radial quantum number nr causes the energy to decrease. The radial part and the angular part of the wave function are defined as hypergeometry functions and visualized with Matlab 2011. The results show that the disturbance of a combination of the Eckart potential and trigonometric Manning Rosen potential can change the radial part and the angular part of the wave function. 展开更多
关键词 Dirac equation Eckart potential trigonometric manning Rosen potential spin symmetric
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Remove Degeneracy in Relativistic Symmetries for Manning–Rosen Plus Quasi-Hellman Potentials by Tensor Interaction
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作者 Mohsen Mousavi Mohammad Reza Shojaei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第11期483-490,共8页
The relativistic Dirac equation under spin and pseudo-spin symmetries is investigated for Manning–Rosen plus quasi-Hellman potentials with tensor interaction. For the first time we consider the Hulthen plus Yukawa fo... The relativistic Dirac equation under spin and pseudo-spin symmetries is investigated for Manning–Rosen plus quasi-Hellman potentials with tensor interaction. For the first time we consider the Hulthen plus Yukawa for tensor interaction. The Formula method is used to obtain the energy eigen-values and wave functions. We also discuss about the energy eigen-values and the Dirac spinors for the Manning–Rosen plus quasi-Hellman potentials for the spin and pseudo-spin symmetry with Formula method. To show the accuracy of the present model, some numerical results are shown in both pseudo-spin and spin symmetry limits. 展开更多
关键词 Dirac equation manning–Rosen potential quasi-Hellman potential tensor interaction formula method
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Relativistic Bound and Scattering Amplitude of Spinless Particles in Modified Schioberg Plus Manning–Rosen Potentials
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作者 B.H.Yazarloo H.Mehraban 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第1期71-75,共5页
By using an approximation for the centrifugal term, we study relativistic bound and scattering states of spin-zero particles in the presence of equal scalar and vector modified Schioberg plus Manning–Rosen potentials... By using an approximation for the centrifugal term, we study relativistic bound and scattering states of spin-zero particles in the presence of equal scalar and vector modified Schioberg plus Manning–Rosen potentials for any quantum numbers n and l. Energy eigenvalues and the scattering amplitude are calculated. Some special cases of the problem are also investigated. 展开更多
关键词 modified Schioberg plus manning–Rosen potentials Klein–Gordon equation bound state scattering state scattering amplitude
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Calibration of Pipe Roughness Coefficient Based on Manning Formula and Genetic Algorithm
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作者 于志强 田一梅 +1 位作者 郑毅 赵新华 《Transactions of Tianjin University》 EI CAS 2009年第6期452-456,共5页
This paper presents a method to calibrate pipe roughness coefficient (i.e., Manning n-factor) with genetic algorithm (GA) under multiple loading conditions. Due to the old pipe age as well as deleting valves and blend... This paper presents a method to calibrate pipe roughness coefficient (i.e., Manning n-factor) with genetic algorithm (GA) under multiple loading conditions. Due to the old pipe age as well as deleting valves and blends in the skeleton of distribution network, most of the pipes in hydraulic model of practical water distribution system (WDS) are rough. The commonly used Hazen-Williams C-factor is therefore replaced by Manning n-factor in calibrating WDS hydraulic model. Adjustment to GA is designed, and the program efficiency is improved. A case study shows that the adjustment can save 60% of the total runtime. About 90% of the relative differences between simulated and observed pressures at monitoring locations are lower than 3%, which suggests that the proposed adjustment to the calibration is efficient and effective. 展开更多
关键词 genetic algorithm CALIBRATION pipe roughness coefficient manning n-factor
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长江沙洲水道洲滩植被阻水影响分析
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作者 李达 杨中华 +1 位作者 张松 张为 《水电能源科学》 北大核心 2025年第2期67-71,48,共6页
针对水库修建后下游洪水位抬升的现象,以长江中游沙洲水道为例,基于现场查勘并结合遥感影像解析和平面二维水动力模型分析洲滩植被对沙洲水道的阻水影响。结果表明,洲滩植被会引起沙洲水道区域平均水位抬升、流速减小,且水位自下游至上... 针对水库修建后下游洪水位抬升的现象,以长江中游沙洲水道为例,基于现场查勘并结合遥感影像解析和平面二维水动力模型分析洲滩植被对沙洲水道的阻水影响。结果表明,洲滩植被会引起沙洲水道区域平均水位抬升、流速减小,且水位自下游至上游抬升幅度沿程增大,洪水流量影响大于中等流量影响;水道断面流速分布呈现洲滩减小,主槽增大的变化趋势,可能造成“槽冲滩淤”;植被阻水影响随植被生长而增大,但影响变幅在减小;防浪林对于沙洲水道右岸流速的调整大于左岸,而矮草/灌木对流速调整的影响则相反。 展开更多
关键词 沙洲水道 遥感解析 植被分布 等效manning系数 阻水影响
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ERAD信号通路中EDEM1和MAN1A1基因多态性与公猪精液品质性状的关联分析
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作者 李亚赛 冯越 +8 位作者 周佳伟 吴俊静 乔木 万绪玲 吴梦华 彭先文 梅书棋 杜志强 张宇 《中国畜牧杂志》 北大核心 2025年第8期178-183,共6页
在前期基因组研究的基础上,本研究从ERAD信号通路中筛选出2个可能影响公猪精液品质性状的候选基因:内质网降解增强α-甘露糖苷酶样蛋白1(ER Degradation Enhancingα-mannosidase-like Protein 1,EDEM1)与α-1,2-甘露糖苷酶(Alpha-Manno... 在前期基因组研究的基础上,本研究从ERAD信号通路中筛选出2个可能影响公猪精液品质性状的候选基因:内质网降解增强α-甘露糖苷酶样蛋白1(ER Degradation Enhancingα-mannosidase-like Protein 1,EDEM1)与α-1,2-甘露糖苷酶(Alpha-Mannosidase,MAN1A1)。通过一代测序发现候选基因EDEM1上存在g.61729627A>T位点,候选基因MAN1A1上存在g.42772917 G>A位点。在大白猪群体中进行关联分析,发现2个多态位点均能显著影响公猪精液品质。其中,EDEM1基因的g.61729627 A>T位点在多个精液性状中表现出显著关联,包括精子密度、有效精子密度、直线运动能力、精子活力、畸形率以及有效精子数;而MAN1A1基因的g.42772917 G>A位点则与精液量、精子密度、有效精子密度、精子活力、畸形率和有效精子数等性状密切相关,且EDEM1基因g.61729627A>T位点和MAN1A1基因g.42772917 G>A位点间存在互作。本文从公猪精液品质角度筛选出一些相关的候选基因和分子标记,为公猪精液品质性状改良提供了分子标记。 展开更多
关键词 SNP 精液品质性状 EDEM1基因 MAN1A1基因 关联分析
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猪A群轮状病毒Taq Man荧光定量RT-PCR检测方法的建立与运用
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作者 林青 康龙滨 +5 位作者 吴瑞森 赵文娟 陈秋勇 王隆柏 周伦江 俞道进 《福建农业学报》 北大核心 2025年第4期370-376,共7页
【目的】建立一种猪A群轮状病毒(porcine rotavirus group A, PoRV A)快速检测方法,用于PoRV检测和流行病学调查。【方法】参考GenBank中猪A群轮状病毒(PoRVA)VP6基因序列(登录号MT025937.1、OP978242.1、PP566178.1)设计特异性引物和探... 【目的】建立一种猪A群轮状病毒(porcine rotavirus group A, PoRV A)快速检测方法,用于PoRV检测和流行病学调查。【方法】参考GenBank中猪A群轮状病毒(PoRVA)VP6基因序列(登录号MT025937.1、OP978242.1、PP566178.1)设计特异性引物和探针,优化反应体系中引物和探针的浓度,建立Taq Man RT-qPCR检测方法,并通过特异性、灵敏性和重复性的结果以及临床应用对该方法进行评价。【结果】该方法可特异性扩增PoRV核酸,最低检出限度为27.0 copies·μL^(-1),灵敏度高于普通RT-PCR 100倍;与猪流行性腹泻病毒(porcine epidemicdiarrheavirus,PEDV)、猪德尔塔冠状病毒(porcinedeltacoronavirus,PDCoV)、猪传染性胃肠炎病毒(transmissible gastroenteritis of swine, TGEV)核酸均无交叉反应;组内和组间变异系数均小于1.10%,重复性好。151份疑似PoRV的临床样品使用RT-qPCR进行检测,结果显示检出率为42.38%(64/151),优于常规RT-PCR的检出率(33.11%,50/151)。【结论】本研究基于猪A群轮状病毒VP6基因,建立了适用于PoRV A检测及其流行病学调查的Taq Man实时荧光定量PCR检测方法,具有灵敏度高、特异性强、重复性好等优势,为猪轮状病毒检测和流行病学调查提供了技术手段。 展开更多
关键词 猪A群轮状病毒 Taq Man探针 荧光定量RT-PCR
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山羊星状病毒Taq Man荧光定量PCR检测方法的建立与应用
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作者 于皓同 马勇杰 +3 位作者 王凯茸 张琪 张淑霞 许信刚 《动物医学进展》 北大核心 2025年第8期7-11,共5页
为建立快速检测山羊星状病毒(Caprine astrovirus)的方法,根据GenBank上收录的山羊星状病毒ORF1ab基因序列(OR652457)设计特异性探针和引物,构建重组质粒。以重组质粒为标准品进行反应条件优化及临床样品检测初步应用,旨在建立一种检测... 为建立快速检测山羊星状病毒(Caprine astrovirus)的方法,根据GenBank上收录的山羊星状病毒ORF1ab基因序列(OR652457)设计特异性探针和引物,构建重组质粒。以重组质粒为标准品进行反应条件优化及临床样品检测初步应用,旨在建立一种检测山羊星状病毒的Taq Man荧光定量PCR方法。结果显示,该方法建立的标准曲线具有良好的线性关系;对牛病毒性腹泻病毒、牛冠状病毒、牛轮状病毒、山羊贝氏柯克斯体、山羊支原体等均无交叉反应;对山羊星状病毒重组质粒标准品最低检测限为2.16×10^(1)copies/μL;批内和批间试验结果稳定,变异系数均小于2%;用建立的方法对收集的陕西省部分山羊场的115份腹泻粪便样品进行检测,结果显示山羊星状病毒阳性率为29.57%,与常规RT-PCR的检测结果符合率为94.78%。该方法为山羊星状病毒快速检测提供了技术支持。 展开更多
关键词 山羊星状病毒 Taq Man荧光定量PCR 检测方法
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IBS诊断标准的演变 被引量:5
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作者 钱家鸣 吕红 《胃肠病学和肝病学杂志》 CAS 2002年第4期330-331,338,共3页
关键词 肠易激综合征 manning标准 罗马标准 诊断标准
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封冻河流阻力研究现况 被引量:9
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作者 魏良琰 《武汉大学学报(工学版)》 CAS CSCD 北大核心 2002年第1期1-9,36,共10页
全面总结了冰盖流阻力研究的进展 .总结了国内外对冰盖流阻力、流速分布、综合糙率、测流方法的研究现况 ,评述了现有的综合糙率公式 ,建议了能兼容完全封冻和不完全封冻的一般公式 ,并相应建立了冰盖流和明流间的自动比拟关系 。
关键词 河流阻力 冰盖流 manning糙率 封冻
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SCIENCE AND TECHNOLOGY
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《China Today》 2025年第9期59-59,共1页
China Completes First Manned Lunar Lander Landing and Takeoff Test China announced that it has successfully completed a comprehensive landing and takeoff test on August 7 for its manned lunar lander at a test site in ... China Completes First Manned Lunar Lander Landing and Takeoff Test China announced that it has successfully completed a comprehensive landing and takeoff test on August 7 for its manned lunar lander at a test site in Huailai County,north China's Hebei Province.The test which was completed on August 6 represents a key step in the development of China’s manned lunar exploration program,and also marks the first time that China has carried out a test of extraterrestrial landing and takeoff capabilities of a manned spacecraft,the China Manned Space Agency said. 展开更多
关键词 landing takeoff test lunar lander manned lunar lander test extraterrestrial landing takeoff capabilities Chinas manned lunar exploration program extraterrestrial landing takeoff capabilities
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A study of the landforms and megafaunal characteristics of the Caiwei Guyot area by manned submersible image datadriven technology
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作者 Zhongjun Ding Xingyu Wang +2 位作者 Chen Liu Guangyang Ma Chanjuan Cao 《Acta Oceanologica Sinica》 2025年第1期147-164,共18页
Scientific and precise evaluations of the megafaunal and landform characteristics of seamounts are important guides for their protection and study.A series of manned and unmanned submersibles have provided invaluable ... Scientific and precise evaluations of the megafaunal and landform characteristics of seamounts are important guides for their protection and study.A series of manned and unmanned submersibles have provided invaluable observational imaging data for the ecological study of seamounts.However,traditional methods of artificial observation of seamount imaging data cannot accurately and efficiently determine the characteristics of megafauna and landforms.This research harnesses data-driven technology to systematically investigate the distributional traits and morphological features of megafaunal organisms,as well as the topographical characteristics,in the Caiwei Guyot region of the western Pacific’s Magellan Seamounts.To construct the landform and megafauna dataset of the Caiwei Guyot region,we used a data preprocessing technology based on image enhancement to provide high-quality imaging data for data-driven technologies.A megafaunal identification and counting algorithm based on YOLOv5(You Only Look Once Version 5)was developed to efficiently assess the abundance,variety,and dominant species of megafauna.Simultaneously,a landform three-dimensional(3D)reconstruction algorithm based on PatchmatchNet was developed to reconstruct the 3D form of the terrain accurately.This study pioneers the application of data-driven technology to deep-sea imaging within the Caiwei Guyot region,offering an innovative approach to accurately and efficiently characterize the region’s unique megafauna and landforms. 展开更多
关键词 manned submersible imaging DATA-DRIVEN Caiwei Guyot LANDFORMS MEGAFAUNA
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MAN主机CPP控制板用PLC替代的实施方案
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作者 李志刚 李振江 +1 位作者 吕红宾 寇忠祥 《天津航海》 2025年第2期20-22,共3页
文章探讨了使用可编程逻辑控制器(PLC)替代MAN主机CPP控制板(ASP12)的可行性和实施方案,结合实际项目,详细地说明了PLC选型、编程设计、系统集成等内容,并研发了ASP12-PLC控制板,旨在为中油海工船舶设备实现升级换代,以提升系统可靠性... 文章探讨了使用可编程逻辑控制器(PLC)替代MAN主机CPP控制板(ASP12)的可行性和实施方案,结合实际项目,详细地说明了PLC选型、编程设计、系统集成等内容,并研发了ASP12-PLC控制板,旨在为中油海工船舶设备实现升级换代,以提升系统可靠性、灵活性、可维护性及经济性。 展开更多
关键词 MAN主机 CPP控制板 ASP12 PLC替代
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重视肠黏膜免疫在肠易激综合征发病机制中的作用 被引量:8
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作者 刘菲 《国际消化病杂志》 CAS 2011年第4期189-191,212,共4页
肠易激综合征(IBS)是临床上最为常见的肠道功能性疾病之一,是指一组包括腹痛、腹胀及排便习惯改变、粪便性状异常为临床表现的症候群。既然定义为一种功能性疾病,首先应该排除形态学、生物化学代谢等方面的异常。关于IBS诊断标准如M... 肠易激综合征(IBS)是临床上最为常见的肠道功能性疾病之一,是指一组包括腹痛、腹胀及排便习惯改变、粪便性状异常为临床表现的症候群。既然定义为一种功能性疾病,首先应该排除形态学、生物化学代谢等方面的异常。关于IBS诊断标准如Manning标准、 展开更多
关键词 肠易激综合征 肠黏膜免疫 发病机制 肠道功能性疾病 manning标准 生物化学代谢 临床表现 排便习惯
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Enzyme-catalyzed synthesis of mannose ester and its enhancement of tanshinone and glycyrrhetinic acid lipid nanoparticles
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作者 Yue Li Jiexuan Wang +1 位作者 Xiuli Wang Xue Guo 《Journal of Traditional Chinese Medical Sciences》 2025年第3期390-401,共12页
Objective:To improve the efficiency of drug delivery,a mannose vinyl stearate mannose ligand(Man ligand)with active liver-targeting properties was synthesized.Methods:Non-aqueous enzymatic synthesis was used to modify... Objective:To improve the efficiency of drug delivery,a mannose vinyl stearate mannose ligand(Man ligand)with active liver-targeting properties was synthesized.Methods:Non-aqueous enzymatic synthesis was used to modify the structure of mannose.Glycyrrhetinic acid-tanshinone lipid nanoparticles(GT-LN)and liver-targeted glycyrrhetinic acid-tanshinone mannose-modified lipid nanoparticles(GT-MLN)were prepared.The physicochemical properties and release profiles of both formulations were evaluated,and their pharmacokinetic behavior and tissue distribution were investigated.Results:The average particle sizes of GT-LN and GT-MLN were 190.20±1.35 and 204.83±3.86 nm,respectively,with corresponding surface Zeta potentials of-28.0±1.68 and-30.24±2.10 mV.The drug release profile of GT-LN conformed to the Higuchi equation,whereas that of GT-MLN followed both the first-order kinetic and RitgerePeppas equations.Both formulations significantly enhanced the gastrointestinal stability of the drug.In vivo studies in mice demonstrated that hepatic GA and TSN concentrations in both groups were significantly higher than those in the original drug suspension group(P=.01).Notably,the concentrations in the GT-MLN group were significantly higher compared to the GTLN group(P=.01).Conclusion:Man ligand was formed via the linkage of vinyl stearate with the hydroxyl group at C-6 in mannose.The Manligand endowed these lipid nanoparticles with obvious active liver-targeting properties.Our results provide an efficient and stable route of drug delivery to the liver with improved drug availability. 展开更多
关键词 Non-aqueous enzyme catalysis Mannose receptor Active liver targeting Lipid nanoparticles Man ligand
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A Spider-Man themed park
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作者 陈萍萍 《疯狂英语(新读写)》 2025年第9期9-11,75,共4页
Shanghai Disney Resort broke ground on a new Spider⁃Man⁃themed land,a major expansion that represents a rising global investment interest in Chinas theme park sector.Located close to Zootopia,the new land includes the... Shanghai Disney Resort broke ground on a new Spider⁃Man⁃themed land,a major expansion that represents a rising global investment interest in Chinas theme park sector.Located close to Zootopia,the new land includes the parks first major Marvel⁃themed attraction-a high⁃energy thrill roller coaster featuring Spider⁃Man,one of the most popular Marvel superheroes,according to the company. 展开更多
关键词 global investment theme park shanghai disney resort marvel roller coaster spider man theme park sector
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