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Compressive holographic sensing simplifies quantitative phase imaging

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Light(Science & Applications) 2023年第6期12卷 946-948页

作者： Jiawei Sun juergen W.Czarske Competence Center for Biomedical Computational Laser Systems(BIOLAS) TU DresdenDresdenGermany Laboratory of Measurement and Sensor System Technique(MST) TU DresdenHelmholtzstrasse 1801069 DresdenGermany Cluster of Excellence Physics of Life TU DresdenDresdenGermany Institute of Applied Physics TU DresdenDresdenGermany

Quantitative phase imaging (QPI) has emerged as method for investigating biological specimen and technical objects. However, conventional methods often suffer from shortcomings in image quality, such as the twin image artifact. A novel computational framework for QPI is presented with high quality inline holographic imaging from a single intensity image. This paradigm shift is promising for advanced QPI of cells and tissues.

关键词： holographic phase shortcomings

Osteoclast-like giant cell tumors of the pancreas and liver

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World Journal of Gastroenterology 2006年第48期12卷 7878-7883页

作者： juergen Bauditz Birgit Rudolph Wolfram Wermke Fourth Department of Medicine Charité University Hospital Berlin Ger-many Institute of Pathology Charité University Hospital Berlin Germany

Osteoclast-like giant cell tumors （OGCT） are rare abdominal tumors, which mainly occur in the pancreas. The neoplasms are composed of two distinct cell populations and frequently show an inhomogenous appearance with cystic structures. However, due to the rarity of these tumors, only very limited clinical data are available. Imaging features and sonographic appearance have hardly been characterized. Here we report on two cases of osteoclast-like giant cell tumors, one located within the pancreas, the other within the liver, in which OGCTs are extremely rare. Both patients were investigated by contrast sonography, which demonstrated a complex, partly cystic and strongly vascularized tumor within the head of the pancreas in the first patient and a large, hypervascularized neoplasm with calcifications within the liver in the second patient. The liver OGCT responded well to a combination of carboplatin, etoposide and paclitaxel. With a combination of surgical resection, radiofrequency ablation and chemotherapy, the patient＇s survival is currently more than 15 too, making him the longest survivor with an OGCT of the liver to date.

关键词： Osteoclast-like giant cell tumor Liver cancer Pancreatic cancer Contrast sonography

Do Near-Solar-System Supernovae Enhance Volcanic Activities on Earth and Neighbouring Planets on Their Paths through the Spiral Arms of the Milky Way, and What Might Be the Consequences for Estimations of Earth’s History and Predictions for Its Future?

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International Journal of Geosciences 2019年第5期10卷 563-575页

作者： Heinz-juergen Brink Institute of Geophysics University of Hamburg Hamburg Germany

Recent observations of young volcanism on the near-Earth terrestrial planets require a new understanding. Magmatic/volcanic episodes on Venus, Mars and Mercury, as well as on Earth’s Moon, are apparently contemporaneous thermal events that accompanied increased magmatic/volcanic activity on Earth, following a 300-Myr cycle. A collateral galactic thermal source in the Milky Way appears to be needed that would predominantly affect the interior of the planets and, perhaps indirectly, Earth’s biosphere, compared to other galactic sources, such as intense cosmic rays or large, rocky bolides. The search for such a source leads to near-Earth supernovae, with their neutrino output, and to the question of whether those neutrinos could act as energy transmitters to heat up the body of Earth, and also enhance its short-term magmatic processes;for example, Cenozoic anorogenic volcanism. This observation challenges present assumptions and paradigms about Earth’s history, and requires the following reconsiderations: 1) the real origin of the end-Cretaceous mass extinction;2) the general radioactive age determinations of rocks;and 3) geodynamic modelling using additional, external heat sources.

关键词： Synchronous Planetary Magmatism Galactic Heat Source Supernovae and White Dwarfs Neutrinos Mass Extinctions

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铝合金薄板搅拌摩擦焊接残余变形的数值分析

金属学报 2009年第2期45卷 183-188页

作者：鄢东洋史清宇吴爱萍 juergen Silvanus 刘园张增磊清华大学机械工程系 European Aeronautic Defence and Space Company Innovation Works Munich 81663Germany

大尺寸6056铝合金薄板经过搅拌摩擦焊接实验后出现了严重的面外变形,虽然变形程度小于熔化焊结果,但已经影响到被焊薄板的装配和使用.为详细研究和预测铝合金薄板在搅拌摩擦焊后的残余变形,以焊接实验条件为基础,建立了搅拌摩擦焊接三... 详细信息

大尺寸6056铝合金薄板经过搅拌摩擦焊接实验后出现了严重的面外变形,虽然变形程度小于熔化焊结果,但已经影响到被焊薄板的装配和使用.为详细研究和预测铝合金薄板在搅拌摩擦焊后的残余变形,以焊接实验条件为基础,建立了搅拌摩擦焊接三维有限元热力耦合分析模型.模型中涉及了利用搅拌头工作转矩计算热输入量、工件和卡具之间的接触热传导、随温度变化的材料模型,以及综合考虑搅拌头机械作用等工作.利用该模型可以得到不对称的纵向残余应力结果,残余变形的趋势在整块板上都与实验结果相同,而且变形量和实验测量值之间的误差在20%以内.

关键词：搅拌摩擦焊铝合金数值模拟残余变形

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搅拌摩擦焊接过程的试验测量及分析

焊接学报 2010年第2期31卷 67-70页

作者：鄢东洋史清宇吴爱萍 juergen Silvanus 刘园清华大学机械工程系北京100084 EADS Company Innovation Works Munich 81663

通过设计一系列搅拌摩擦焊接试验,详细测量和分析焊接温度场分布、搅拌头机械载荷、残余应力和残余变形.试验发现,搅拌摩擦焊的温度测量结果的准确性取决于采样频率和热电偶的定位方法;搅拌头的机械载荷主要表现为下压力和扭矩,它们在... 详细信息

通过设计一系列搅拌摩擦焊接试验,详细测量和分析焊接温度场分布、搅拌头机械载荷、残余应力和残余变形.试验发现,搅拌摩擦焊的温度测量结果的准确性取决于采样频率和热电偶的定位方法;搅拌头的机械载荷主要表现为下压力和扭矩,它们在准稳态焊接的条件下会保持稳定,但取值随焊接参数的变化而发生相应变化;焊接残余应力的主要成分是纵向应力,焊缝区域内呈现较高水平的拉应力,分布呈不对称的双峰特征;薄板的焊接变形具有马鞍形和反马鞍形两种形态,且变形程度受到薄板尺寸、旋转频率和焊接速度的影响.

关键词：搅拌摩擦焊温度场搅拌头机械载荷残余应力残余变形

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涎腺膜性基底细胞腺瘤的组织发生学研究

中华口腔医学杂志 2000年第1期35卷 31-33,I004页

作者：俞光岩 juergen Ussmueller Karl Donath 北京医科大学口腔医学院口腔颌面外科 100081 Institute of Pathology University of Hamburg

目的　探讨涎腺膜性基底细胞腺瘤的组织发生和发展过程。方法　对 12例涎腺膜性基底细胞腺瘤患者进行组织病理学和免疫组织化学研究。结果　 4例患者均可见肿瘤周围的腺体组织中有多灶性纹管增殖 ,其最早期的改变为纹管基底细胞增殖 ,... 详细信息

目的　探讨涎腺膜性基底细胞腺瘤的组织发生和发展过程。方法　对 12例涎腺膜性基底细胞腺瘤患者进行组织病理学和免疫组织化学研究。结果　 4例患者均可见肿瘤周围的腺体组织中有多灶性纹管增殖 ,其最早期的改变为纹管基底细胞增殖 ,持续不断的导管增殖导致了微小腺瘤的形成。结论　纹管基底细胞的增殖明显参与涎腺膜性基底细胞腺瘤的形成 ,并在其中起主要作用。

关键词：涎腺肿瘤免疫组织化学基底细胞腺癌

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搅拌摩擦焊接的热力耦合分析模型

机械工程学报 2010年第16期46卷 106-112页

作者：鄢东洋史清宇吴爱萍 juergen Silvanus 张增磊清华大学机械工程系北京100084 欧盟太空防卫及空间技术集团技术革新实验室慕尼黑81663德国

随着数值模拟技术在搅拌摩擦焊接研究中的应用日益广泛,对模型本身的准确程度要求越来越高,因而针对数值分析模型的研究显得更有意义。通过分析搅拌摩擦焊接热力耦合计算方面的相关资料,结合实际开展的搅拌摩擦焊接试验以及试验过程中... 详细信息

随着数值模拟技术在搅拌摩擦焊接研究中的应用日益广泛,对模型本身的准确程度要求越来越高,因而针对数值分析模型的研究显得更有意义。通过分析搅拌摩擦焊接热力耦合计算方面的相关资料,结合实际开展的搅拌摩擦焊接试验以及试验过程中对部分物理量的测量和分析,建立更加完善的搅拌摩擦焊接数值模拟模型。对生热过程、材料模型、夹具约束以及搅拌头机械载荷作用都进行细致分析和探讨,在新模型中采用被焊材料的剪切极限作为生热驱动力,考虑被焊材料的力学性能随温度和温度历史发生变化,建立夹具和试板之间的接触关系,并在力学分析模型中将搅拌头机械载荷简化考虑。利用新建立的数值分析模型对铝合金薄板搅拌摩擦焊接过程进行模拟,得到和试验结果吻合较好的温度场、残余应力和变形结果。

关键词：搅拌摩擦焊数值模拟残余应力残余变形

Quality Focused Apiculture Sector Value Chain Development in Ethiopia

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Journal of Agricultural Science and Technology(A) 2017年第2期7卷 107-116页

作者： Negash Bekena juergen Greiling Ethiopian Apiculture Board P.O. Box 2307 Addis Ababa Ethiopia

Ethiopia is an ＂apiculture country＂ with more than 10 million honey bee colonies. Ethiopia is also a ＂honey country＂; the annual honey and beeswax production potentials are 550,000 and 50,000 metric tons, respectively, with about one tenth actually produced. Since 2008, Ethiopia is EU ＂third country＂ listed for the export of honey. However, the national research system identified serious bottlenecks, such as traditional smallholder level production with very low productivity and problematic supply chain; quality issues, including adulteration; lack of access to credit; constrained input supply chain and input quality issues. This paper illustrates how quality defects have been addressed in a quality focused value chain development （VCD） approach, with focus on： creating a favorable policy ground; implementing regional, national and continental multi-stakeholder-platforms （MSPs） for dialogue; information and knowledge sharing and sector advocacy; strengthening supportive sector organizations along the value chain; networking and market intelligence, including exposition and conference organization; expansion of research centers and activities; laboratory qualification for intematioual accreditation. Many components are implemented through the largest national apiculture sector development programme called Apiculture Scaling-Up Programme for Income and Rural Employment （ASPIRE）, which transfers innovations to more than 30,000 beekeepers. Among others, ASPIRE was instrumental in qualifying national testing facilities, which in turn led to product quality improvement. However, more action is required in the fields of business-to-business （B2B） linkages, research, education and training, as well as in making so far voluntary practices mandatory. This also calls for full traceability and routine quality testing along the value chain.

关键词： Ethiopia apiculture value chain development product quality.

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教育全球化:进程与话语

比较教育研究 2002年第S1期23卷 58-62页

作者： juergen Schriewer 冯巍德国洪堡大学教育部人文社会科学重点研究基地北京师范大学比较教育研究中心

全球化或国际化是当今世界教育体系以及教育理论和实践的显著特征。对于教育全球化进程和与之相关的教育话语,既要认识到它们之间密不可分的关系,又不能混为一谈,而是需要从恰当的理论视角对之进行审视和分析。在本文中,作者首先概述了... 详细信息

全球化或国际化是当今世界教育体系以及教育理论和实践的显著特征。对于教育全球化进程和与之相关的教育话语,既要认识到它们之间密不可分的关系,又不能混为一谈,而是需要从恰当的理论视角对之进行审视和分析。在本文中,作者首先概述了全球化交流的背景和相关话语,接着对全球化与特定民族文化结构的关系进行了分析,最后介绍了洪堡大学比较教育研究中心的有关成果,包括对研究教育全球化的不同理论视角的分析和比较、对国际性的多元解释等。

关键词：教育全球化话语