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Quantum model simulations of attosecond electron diffraction

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Science China(Physics,mechanics & Astronomy) 2010年第6期53卷 987-1004页

作者： Peter baum Jrn mANZ Axel SCHILD max-Planck-Institute of Quantum Optics and Ludwig-Maximilians-Universitt München Freie Universitt Berlin Institut für Chemie und Biochemie

Ultrafast diffraction with free attosecond electron pulses promises insight into the four-dimensional motion of charge density inatoms,molecules and condensed matter. Here we consider the quantum dynamics of the electron-electron scattering process on anattosecond time scale. By numerically solving the time-dependent two-electron Schrdinger equation,we investigate the interactionof an incoming keV-range electron wavepacket by the bound electron of an aligned H+2 molecule,using a one-dimensional *** findings reveal the ratio of elastic to inelastic contributions,the role of exchange interaction,and the influence of the molecularelectron density to diffraction. momentum transfer during the scattering process,from the incoming to the bound electron mediatedby the nuclei,leaves the bound electron in a state of coherent oscillation with attosecond recurrences. Entanglement causes relatedstate-selective oscillations in the phase shift of the scattered electron. Two scenarios of distinguishable and indistinguishable freeand bound electrons yield equivalent results,irrespective of the electronic spins. This suggests to employ the scenario of distinguishable electrons,which is computationally less demanding. Our findings support the possibility of using electron diffraction forimaging the motion of charge density,but also suggest the application of free electron pulses for inducing attosecond dynamics.

关键词： ultrafast electron diffraction scattering theory attosecond dynamics entanglement coherence

On the radiative Properties of Ice Clouds:Light Scattering, remote Sensing,and radiation Parameterization

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Advances in Atmospheric Sciences 2015年第1期32卷 32-63页

作者： Ping YANG Kuo-Nan LIOU Lei BI Chao LIU Bingqi YI Bryan A.baum Department of Atmospheric Sciences Texas A&M University College Station Joint Institute for regional Earth System Science and Engineering and Department of Atmospheric and Oceanic SciencesUniversity of California Space Science and Engineering Center University of Wisconsin-Madison

Presented is a review of the radiative properties of ice clouds from three perspectives： light scattering simulations, remote sensing applications, and broadband radiation parameterizations appropriate for numerical models. On the subject of light scattering simulations, several classical computational approaches are reviewed, including the conventional geometric-optics method and its improved forms, the finite-difference time domain technique, the pseudo-spectral time domain technique, the discrete dipole approximation method, and the T-matrix method, with specific applications to the computation of the singlescattering properties of individual ice crystals. The strengths and weaknesses associated with each approach are *** reference to remote sensing, operational retrieval algorithms are reviewed for retrieving cloud optical depth and effective particle size based on solar or thermal infrared（Ir） bands. To illustrate the performance of the current solar- and Ir-based retrievals, two case studies are presented based on spaceborne observations. The need for a more realistic ice cloud optical model to obtain spectrally consistent retrievals is demonstrated. Furthermore, to complement ice cloud property studies based on passive radiometric measurements, the advantage of incorporating lidar and/or polarimetric measurements is *** performance of ice cloud models based on the use of different ice habits to represent ice particles is illustrated by comparing model results with satellite observations. A summary is provided of a number of parameterization schemes for ice cloud radiative properties that were developed for application to broadband radiative transfer submodels within general circulation models（GCms）. The availability of the single-scattering properties of complex ice habits has led to more accurate radiation parameterizations. In conclusion, the importance of using nonspherical ice particle models in GCm simulations for climate studies is

关键词： ice clouds light scattering remote sensing radiative property parameterization

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CAD/CAm技术在脚医学中的应用

计算机辅助设计与图形学学报 2002年第4期14卷 324-328页

作者：伍晓宇 Chin Sheng Chen Ira m.baum 深圳大学工程技术学院 Industrial&System Engineering Florida International University Baptist’s Hospital 8940 N.Kendall DriveSuite801 EMiamiFL33176.USA

将CAD/CAm技术与脚医学结合 ,研究开发脚支撑设计制造系统 ,包括脚底曲面数据的读取及处理 .根据医疗规则完成三维脚支撑模型的构造、平衡及光滑处理 ,激光快速原型文件和铣削加工刀具轨迹的自动生成等 .

关键词： CAD CAm 脚支撑脚扫描仪脚医学平足脚

major histocompatibility complex I upregulation in clear cell renal cell carcinoma is associated with increased survival

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Asian Journal of Urology 2016年第2期3卷 75-81页

作者： rishi r.Sekar Claire m.De La Calle Dattatraya Patil Sarah A.Holzman Yor.m.baum Umer Sheikh Jonathan H.Huang Adeboye O.Osunkoya Brian P.Pollack Haydn T.Kissick Kenneth Ogan Viraj A.master Department of Urology Emory University School of MedicineAtlantaGAUSA Department of Pathology Emory University School of MedicineAtlantaGAUSA Department of Dermatology Emory University School of MedicineAtlantaGAUSA The Atlanta VA medical Center DecaturGAUSA

Objective:To examine the prognostic value of tumor major histocompatibility complex I(mHCI)expression on survival and recurrence in patients with clear cell renal cell carcinoma(rCC).methods:Fifty-three patients that underwent nephrectomy at our institution for clear cell rCC(T1eT3)with4 years of follow-up were queried from our nephrectomy *** staining for mHCI was performed on tumor specimens and mHCI expression was quantified with an automated image analysis *** were divided into high and low mHCI expression groups in order to study the relationship between mHCI expression and prognosis using the Kaplanemeier method and log-rank ***:Overall survival and recurrence free survival were increased in the high mHCI expression group compared to the low mHCI expression group(log-rank,p=0.036 and p=0.028,respectively).Patients alive at the end of the study had higher mHCI expression(mean positivity score 0.82)than those that died of disease(mean positivity score 0.76,t test,p=0.030).Patients that did not develop recurrence during the study period had higher mHCI expression(mean positivity score 0.83)than those that did develop recurrence(mean positivity score 0.78),but this difference was not significant(t test,p =0.079).

关键词： renal cell carcinoma Prognosis mHCI Biomarker

Differentially Expressed Genes between Two Barley Cultivars Contrasting in Drought Tolerance

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分子植物育种 2007年第2期5卷 181-183页

作者： P.G. Guo　 m. baum　 r.H. Li 　 S. Grando r.K. Varshney　 J. Valkoun　 S. Ceccarelli　 A. Grane College of Life Science Guangzhou University Guangzhou 510006 China International Centre for Agricultural research in the Dry Areas （ICArDA） P.O. Box 5466 Aleppo Syria Institute of Plant Genetics and Crop Plant research （IPK） Gatersleben Germany

Drought tolerance is a key trait for increasing and stabilizing barley productivity in dry areas. A number of genes have been described that respond to drought at the transcriptional level (Seki et al., 2002; Cheong e... 详细信息

关键词：基因表达栽培品种干旱耐受性能

^(99)Tc^m标记抗粘蛋白mcAb乳腺癌放射免疫显像的临床研究

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中华核医学杂志 2000年第2期20卷 75-77页

作者：吴浩荣吴锦昌 richardP.baum 苏州医学院附属第二医院外科 215004 苏州医学院附属第二医院核医学科 215004 Department of molecular Nuclear medicine

目的　评价99Tcm 标记抗乳腺癌粘蛋白单克隆抗体 (mcAb)放射免疫显像 (rII)诊断乳腺癌的临床价值。方法　选择 17例乳腺肿瘤患者进行rII。结果　 9例原发性乳腺癌中 8例rII阳性 ,灵敏度 88 89% ;5例原发性乳腺癌伴腋淋巴结转移及 1例右... 详细信息

目的　评价99Tcm 标记抗乳腺癌粘蛋白单克隆抗体 (mcAb)放射免疫显像 (rII)诊断乳腺癌的临床价值。方法　选择 17例乳腺肿瘤患者进行rII。结果　 9例原发性乳腺癌中 8例rII阳性 ,灵敏度 88 89% ;5例原发性乳腺癌伴腋淋巴结转移及 1例右乳腺浸润性导管癌根治术 5a后出现右腋淋巴结转移 ,rII发现其中 5例出现淋巴结转移 ;而 6例乳腺良性病变和 1例右乳腺单纯癌根治术7a后随访 ,rII阴性。结论　99Tcm 标记抗粘蛋白mcAbrII可作为乳腺癌特异性诊断的重要辅助手段 ,并对淋巴结转移、术后复发等具有一定的诊断价值。

关键词： mcAb 乳腺癌锝99m 放射免疫显像单克隆抗体

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约翰·D·罗伯兹荣获美国化学会的最高奖赏

世界科学 1987年第10期 45-46+59页

作者： rudy m.baum 廖德仲

约翰·D·罗伯兹(John ***)是加利福尼亚理工学院的化学教授。他由于对化学的贡献,被提名为1987年普利策奖获得者。普利策奖章是美国化学会的最高荣誉奖。罗伯兹可能由于他在核磁共振光谱方面的工作为人们所熟知。本世纪五十年代中期,... 详细信息

约翰·D·罗伯兹(John ***)是加利福尼亚理工学院的化学教授。他由于对化学的贡献,被提名为1987年普利策奖获得者。普利策奖章是美国化学会的最高荣誉奖。罗伯兹可能由于他在核磁共振光谱方面的工作为人们所熟知。本世纪五十年代中期,他是最先认识到核磁共振潜力的人之一。他在将质子核磁共振发展成为有机化学最强有力的工具的过程中,是一位中心人物。接着,他又研究了除氢之外的核,发展了氟—19,碳—13,氮—15核磁共振光谱,使之仪器化。在此之前,罗伯兹就以其分子轨道计算,小环重排的机理研究以及亲核芳香取

关键词：重排反应有机化学家核磁共振光谱消除反应消去反应双分子反应质子核磁共振天然丰度卡特美国化学会约翰

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化学的前沿——簇合物和光化学

世界科学 1991年第2期 8-9页

作者： rudy m.baum 刘兵

最近在新奥尔良举行的美国科学发展协会(AAAS)年会上,"化学的前沿"专题讨论会的两个主题就是簇合物化学和光化学.过渡金属、碳和硅原子簇化合物为化学家们研究固体表面特性提供了强有力的新工具.在许多实验中,

关键词：簇合物激光蒸发马利曼迪激光加工光化学硅原子马格雷化学键悬空键

创造四倍体小黑麦的新方法及其在培育多倍体上的应用

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农业新技术新方法译丛 1989年第6期 1-4,10页

作者： baum,m 莫鉴国