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Journal of Iron and Steel Research(International) 2012年第8期19卷 17-24页

作者： mróz sebastian Czestochowa University of Technology

Change in the temperature of band over its length, associated with the stock being non-uniformly heated in the furnace, influences the variations in the magnitudes of energy-force parameters. Using the FEM (Finite Element Model) programs for the computation of the values of the energy-force parameters can take into account the distribution of temperature over the band length. The mathematical model of the computer program Forge2008 was used to theoretically examine the energy-force parameters and plastic metal flow in the roughing stands of the continuous rolling mill. The results of experimental investigation of influence of the non-uniform temperature distribution were presented on the metallic charge length on the energy and force parameters and dimensions of the band during round bars rolling. Thermovision monitoring energy and force parameters monitoring were carried out in continuous rolling mill D350 in one of the Polish industrial plants. On the basis of obtained results, it could be stated that non-uniform distribution of temperatures along the charge length causes local increase of energy and force parameters values and also such distribution affects the local increase of the width of rolled band. The rolling process of charge with non-uniform distribution of temperature could lead to exceeding required dimensional tolerances of the final products.

关键词： groove-rolling energy parameter force parameter numerical technique FEM

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Geographical range evolution of the genus Polypedates(Anura:Rhacophoridae)from the Oligocene to present

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zoological Research 2021年第1期42卷 116-123页

作者： Li-Mei Yuan Xi-Ling Deng De-Chun Jiang sebastian Klaus Nikolai LOrlov Kong Yang Jia-Tang Li Institute of Qinghai-Tibetan Plateau Southwest Minzu UniversityChengduSichuan 610041China CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengduSichuan 610041China Department of Ecology and Evolution J.W.Goethe-UniversitätFrankfurt/M.Hessen 60438Germany zoological Institute Russian Academy of SciencesSt.Petersburg 199034Russia Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesNay Pyi Taw 05282Myanmar CAS Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunmingYunnan 650223China University of Chinese Academy of Sciences BeijingChina

DEAR EDITOR,Currently,the genus Polypedates comprises 26 species distributed in South,Southeast,and East *** of their relatively low dispersal capability and intolerance to seawater,this genus is ideal for the study of terrestrial range evolution that extends into the island archipelagos of southeastern *** this study,based on data compiled for Polypedates from previous studies and partial mitochondrial and nuclear genes collected in this study,we performed systematic biogeographical *** confirmed a Sundaland origin for the extant genus and showed northward dispersal into mainland Southeast Asia and Asia,which coincided with the timing of paleoclimatic change from the Oligocene to Middle *** fluctuations had a profound impact on species diversification within the genus ***,the Red River did not mediate species exchange between Southeast Asia and mainland Asia until the end of the Miocene,with the sudden onset of northward dispersal in several clades independently at that ***,the lineage of widespread insular *** strongly supports the hypothesis of terrestrial connection between island archipelagos of Southeast Asia during the Mid-Pleistocene paleoclimate *** biogeographical analysis also supports the recent introduction of *** to the Philippines and Ryukyus,as previously suggested.

关键词： mainland northward evolution

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急性硬脊膜外血肿的mrI研究

中华放射学杂志 2003年第10期37卷 912-916页

作者：徐文坚徐爱德 sebastian Lange 青岛大学医学院附属医院放射科 266003 Department of Radiology Knappschafts Hospital RecklinghausenRuhr University Bochum

目的　探讨急性硬脊膜外血肿 (ASEH)的发病机制、mrI表现特征及鉴别诊断。方法15例ASEH病人 ,男 8例 ,女 7例 ,平均 37.8岁。 5例有脊柱损伤史 ,1例有脊柱手术史 ,1例有腰硬脊膜穿刺史 ,其余 8例无特殊病史。 11例经手术证实 ,2例经CT... 详细信息

目的　探讨急性硬脊膜外血肿 (ASEH)的发病机制、mrI表现特征及鉴别诊断。方法15例ASEH病人 ,男 8例 ,女 7例 ,平均 37.8岁。 5例有脊柱损伤史 ,1例有脊柱手术史 ,1例有腰硬脊膜穿刺史 ,其余 8例无特殊病史。 11例经手术证实 ,2例经CT引导穿刺抽吸治疗并证实 ,2例经临床相应检查及随访证实。所有病人均行矢状面SET1WI和快速SE(FSE)或SET2 WI。 12例行横轴面FSET2 WI ,8例行SET1WI。 4例行SET1WI增强扫描。结果　 15例血肿共发生于 18个脊柱节段 ,其中 6例次 (6 /18)位于颈段、9例次 (9/18)位于胸段、3例次 (3/18)位于腰段。 7例次 (7/18)血肿位于硬膜囊前方 ,11例次 (11/18)位于硬膜囊后方。血肿累及 1～ 13个椎体高度 ,平均 4 .87个椎体高度。T1WI上 ,所有血肿与脊髓之间均显示有线样低信号区。T2 WI矢状面和横轴面上 ,分别有 4例(4/15 )和 8例 (8/12 )在血肿与蛛网膜下腔之间显示有低信号线。矢状面上 13例 (13/15 )血肿呈长梭形 ,横轴面上均呈双凸镜形或半圆形。SET1WI上 ,5例呈等T1信号 ,6例呈短T1信号 ,4例呈等、短T1混杂信号 ;T2 WI上 ,5例呈短T2 信号 ,10例呈短、长T2 混杂信号。 4例增强扫描无特异性。结论　ASEH的mrI表现具有特征性。

关键词：急性硬脊膜外血肿 mrI 磁共振成像发病机制鉴别诊断

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Quantitative T2＊-Mapping of the Knee Using a Spoiled Gradient Echo Sequence at 3 Tesla： Preliminary Results

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Journal of Pharmacy and Pharmacology 2014年第1期2卷 59-69页

作者： Georg Riegler Xeni Deligianni Vladimir Juras Stefan zbjgfi sebastian Apprich Pavol Szomolanyi Michael Weber Oliver Bieri Siegfried Trattnig Department of Biomedical Imaging and Image-guided Therapy MR Center of Excellence for High Field MR Medical Universityof Vienna Vienna 1090 Austria Department of Radiology Division of Radiological Physics University of Basel Hospital Basel 4031 Switzerland Department of Imaging Methods Institute of Measurement Science Slovak Academy of Sciences Bratislava 84104 Slovakia

Purpose: To evaluate a me-vTE-SPGR (multi echo variable TE Spoiled Gradient Echo Sequence) approach for quantitative T2* mapping of the ME (menisci), the PT (patellar tendon), the ACL (anterior cruciate ligament), the PCL (posterior cruciate ligament) and to compare the results between normal and pathological tissue of the ME in the knee joint at 3T (3 Tesla). Methods: Eighteen consecutive knee patients (35.7 ± 11.6 years) were examined on 3T. In addition to standard morphological mrI, T2*-maps were derived from a 0.7 mm isotropic me-vTE-SPGR scan. T2*-values were assessed by two independent observers using an ROI analysis for the ME (4 different regions: posterior and anterior horn of the medial and lateral meniscus), PT, ACL and PCL. Intra-class correlation between readers was calculated. Results: On morphological mrI, the PT, ACL and PCL were diagnosed as normal in all cases. Degenerative meniscus and meniscal tears were diagnosed in 13 cases and 9 cases, respectively. T2*-values of the menisci on me-vTE-SPGR scans, in relation to morphological imaging, were normal (N = 50; 6.0 ± 0.9 ms); degenerative meniscus (N = 13; 8.0 ± 1.6 ms); meniscal tears (N = 9; 12.9 ± 3.9 ms), with significant differences between all groups (P < 0.05)/ significantly higher T2*-values in degenerative meniscus and meniscal tears. Mean T2* relaxation times for the PT, ACL and PCL were 2.9 ± 0.8 ms, 8.4 ± 1.6 ms and 8.9 ± 1.3 ms respectively. Intra-class correlation values between readers for the ME, PT, ACL and PCL were R2 = 0.962, R2 = 0.927, R2 = 0.594 and R2 = 0.648, respectively. Conclusion: Isotropic 3D (three-dimensional) me vTE-SPGR imaging is able to quantify T2* values of multiple tissues in the knee joint with short T2 relaxation times.

关键词：药剂学药理学药学数学物理学化学

Using statistics and mathematical modelling to understand infectious disease outbreaks:COVID-19 as an example

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Infectious Disease Modelling 2020年第1期5卷 409-441页

作者： Christopher E.Overton Helena B.Stage Shazaad Ahmad Jacob Curran-sebastian Paul Dark Rajenki Das Elizabeth Fearon Timothy Felton Martyn Fyles Nick Gent Ian Hall Thomas House Hugo Lewkowicz Xiaoxi Pang Lorenzo Pellis Robert Sawko Andrew Ustianowski Bindu Vekaria Luke Webb Department of Mathematics University of ManchesterUK IBM Research Hartree CentreSciTech DaresburyUK Department of Global Health and Development London School of Hygiene and Tropical MedicineUK Emergency Response Department Public Health EnglandUK Division of Infection Immunity and Respiratory MedicineNIHR Biomedical Research CentreUniversity of ManchesterUK Department of Virology Manchester Medical Microbiology PartnershipManchester Foundation TrustUK Regional Infectious Diseases Unit North Manchester General HospitalUK School of Medical Sciences University of ManchesterUK Intensive Care Unit Wythenshawe HospitalManchester University NHS Foundation TrustUK Department of Health Sciences University of ManchesterUK Department of Mathematical Sciences University of LiverpoolUK The Alan Turing Institute UK Manchester Academic Health Sciences Centre UK Critical Care Unit Salford Royal HospitalNorthern Care Alliance NHS GroupUK

During an infectious disease outbreak,biases in the data and complexities of the underlying dynamics pose significant challenges in mathematically modelling the outbreak and designing *** by the ongoing response to COVID-19,we provide a toolkit of statistical and mathematical models beyond the simple SIR-type differential equation models for analysing the early stages of an outbreak and assessing *** particular,we focus on parameter estimation in the presence of known biases in the data,and the effect of non-pharmaceutical interventions in enclosed subpopulations,such as households and care *** illustrate these methods by applying them to the COVID-19 pandemic.

关键词： COVID-19 Epidemic modelling Parameter estimation Outbreak Bias Intervention

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骶骨衰竭骨折mrI研究

实用放射学杂志 2005年第11期21卷 1172-1175页

作者：徐文坚徐爱德 S.Lange 青岛大学医学院附属医院放射科 Department of Radiology Knappschafts-Hospital Recklinghausen Ruhr-University Bochum Germany 山东青岛266003

目的探讨骶骨衰竭骨折的mr I表现特征及其诊断价值。方法21例病人,女19例,男2例,平均年龄72.4岁。所有病人均有骨质疏松,其中7例为盆腔肿瘤放疗后发病。mr I检查使用矢状位、横轴位和冠状位SE T1W I、FSE T2W I和脂肪抑制FSET2W I。其... 详细信息

目的探讨骶骨衰竭骨折的mr I表现特征及其诊断价值。方法21例病人,女19例,男2例,平均年龄72.4岁。所有病人均有骨质疏松,其中7例为盆腔肿瘤放疗后发病。mr I检查使用矢状位、横轴位和冠状位SE T1W I、FSE T2W I和脂肪抑制FSET2W I。其中14例同时行SE T1W I增强扫描。所有病人均同时行X线平片、CT平扫检查,其中14例行同位素扫描以证实诊断。结果21例共发生37侧骶骨耳部骨折,其中16例(76.2%)为双侧骨折,5例(23.8%)为单侧骨折。37侧骨折中,32侧(86.5%)显示“蛇形”低信号骨折线。所有病例均显示片状或三角形骨折周围水肿区呈长T1长T2异常信号。14例增强扫描,骨折线均无强化,水肿区呈不均匀强化。3例合并其他部位多发性不全骨折。结论mr I诊断骶骨衰竭骨折具有特征性,可显示骨折线及骨折周围水肿区。

关键词：骶骨衰竭骨折磁共振成像诊断

Feasibility of real-time magnetic resonance imaging-guided endomyocardial biopsies:An in-vitro study

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World Journal of Cardiology 2015年第7期7卷 415-422页

作者： Dirk Lossnitzer sebastian A Seitz Birgit Krautz Bernhard Schnackenburg Florian André Grigorios Korosoglou Hugo A Katus Henning Steen Department of Cardiology University Hospital Heidelberg Philips Medical Systems

AIM: To investigate if magnetic resonance(mr)-guided biopsy can improve the performance and safety of such procedures. METHODS: A novel mr-compatible bioptome was evaluated in a series of in-vitro experiments in a 1.5T magnetic resonance imaging(mrI) system. The bioptome was inserted into explanted porcine and bovine hearts under real-time mr-guidance employing a steady state free precession sequence. The artifact produced by the metal element at the tip and the signal voids caused by the bioptome were visually tracked for navigation and allowed its constant and precise localization. RESULTS: Cardiac structural elements and the target regions for the biopsy were clearly visible. Our method allowed a significantly better spatial visualization of the bioptoms tip compared to conventional X-ray guidance. The specific device design of the bioptome avoided inducible currents and therefore subsequent heating. The novel mr-compatible bioptome provided a superior cardiovascular magnetic resonance(imaging) soft-tissue visualization for mr-guided myocardial biopsies. Not at least the use of mrI guidance for endomyocardial biopsies completely avoided radiation exposure for both patients and ***: mrI-guided endomyocardial biopsies provide a better than conventional X-ray guided navigation and could therefore improve the specificity and reproducibility of cardiac biopsies in future studies.

关键词： Endomyocardial biopsy Cardiovascular magnetic resonance(imaging) Magnetic resonance imaging-guided interventions Real-time imaging

能够在高心律下同步产生心脏T1图像，动态影像以及预反转恢复图像的SALLI方法初始研究

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中国医疗设备 2012年第1期27卷 1-7页

作者： Daniel R. Messroghli, MD Sarah Nordmeyer, MD Martin Buehrer, PhD sebastian Kozerke, PhD Thore Dietrich, PhD Elena Kaschina, MD Peter M. Becher, MD Thomas Hucko, MD Felix Berger, MD Christoph Klein, MD Titus Kuehne, MD 郭悦（翻译）苏东东（翻译）郭赤（审校）不详武汉大学人民医院湖北武汉430060 广州军区武汉总医院湖北武汉430070

目的开发一种综合评估高心率小动物心功能和组织特性的mr成像方法。材料与方法所有的动物实验研究均得到当地动物保护委员会批准。小动物Look—Locker反转恢复（SALLI）研究是在临床上配备了70ram电磁线圈的3．0Tmr上实施的。SALLI包括... 详细信息

目的开发一种综合评估高心率小动物心功能和组织特性的mr成像方法。材料与方法所有的动物实验研究均得到当地动物保护委员会批准。小动物Look—Locker反转恢复（SALLI）研究是在临床上配备了70ram电磁线圈的3．0Tmr上实施的。SALLI包括，分段、心电门控以及多模重建体系的预反转恢复Look—Locker型脉冲序列。特别是暂时欠采样和径向非平衡稳态自由进动技术的应用，分别能加快数据采集速度及减少运动伪影的产生。采用9个琼脂糖凝胶体模研究不同序列的设置。在体研究中，10只SD（Sprague—Dawley）大鼠用于评估注射钆喷酸二甲葡胺前、后的正常T1值。7只采用外科法产生急性心肌梗死的大鼠用于测试心肌损伤检测的可行性。采用线性回归分析方法对离体组织T1的变化进行了研究，并对在体组织梗死区域与远端区域T1的差别以Wilcoxon秩和检验法进行检验。结果体模研究阐述了T1测定的系统状态，并通过使用简单的线性校正算法使T1的误差减少到（1．3±7．4）％。增强前、后的心肌层及血液的T1值处于狭窄的正常范围内。SALL1展示了在梗塞区域内的运动功能减退（通过动态图像），心肌水肿（通过对比增强之前的T1图像）以及心肌坏死（通过对比用钆增强之后的T1图像以及延迟的钆增强图像）。结论该mr成像方法使高心率心肌T1图像、动态图像以及预反转恢复序列图像这三者同步生成成为了现实。对于在高心率下心肌T1图像变化、功能以及延迟的钆增强图像，可以用SALLI实现其同步性和时效性进行评价。

关键词：动态图像反转恢复同步性动态影像急性心肌梗死秩和检验法心脏心律