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An Event Horizon Imager(EHI) Mission Concept Utilizing Medium Earth Orbit sub-mm Interferometry

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空间科学学报 2021年第2期41卷 211-233页

作者： KUDRIAsHOV V MARTIN-NEIRA M ROELOFs F FALCKE H BRINKERINK C BARYsHEV A HOGERHEIJde M YOUNG A POURsHAGHAGHI H KLEIN-WOLT M MOsCIBRODZKA M DAVELAAR J BARAT I DUEsMANN B VALENTA V PERDIGUEs ARMENGOL J M de WILde D MARTIN IGLEsIAs P ALAGHA N van deR vorst M department of Astrophysics/IMAPP Radboud University NijmegenP.O.Box 90106500 GL Nijmegenthe Netherlands EsTEC/EsA Keplerlaan 12201 A2 Noordurigkthe Netherlands Mar Planck Institute for Radio Astrorny Auf dem Higel 69D-53121 Bon(Endenich)Germany University of Groningen Landleven 129747 AD Groningenthe Netherlands Leiden Observatory Leiden UniversityPO Box 95132300 RALeidenthe Netherlands Anton Pannekoek Institute for Astronomy University of AmsterdamScience Park 9041098 XHAmsterdamthe Netherlands Center for Computational Astrophysics Flatiron Institute162 Fifth AvenueNew YorkNY 10010USA

submillimeter interferometry has the potential to image supermassive black holes on event horizon scales,providing tests of the theory of general relativity and increasing our understanding of black hole accretion *** Event Horizon Telescope(EHT) performs these observations from the ground,and its main imaging targets are sagittarius A~* in the Galactic Center and the black hole at the center of the M87 ***,the EHT is fundamentally limited in its performance by atmospheric effects and sparse terrestrial(u,v)-coverage(Fourier sampling of the image).The scientific interest in quantitative studies of the horizon size and shape of these black holes has motivated studies into using space interferometry which is free of these *** resolution considerations and interstellar scattering effects push the desired observing frequency to bands above 500 *** paper presents the requirements for meeting these science goals,describes the concept of interferometry from Polar or Equatorial Medium Earth Orbits(PECMEO) which we dub the Event Horizon Imager(EHI),and utilizes suitable space technology *** this concept,two or three satellites orbit at slightly different orbital radii,resulting in a dense and uniform spiral-shaped(u,v)-coverage over *** local oscillator signals are shared via an inter-satellite link,and the data streams are correlated on-board before final processing on the ***-satellite metrology and satellite positioning are extensively employed to facilitate the knowledge of the instrument position vector,and its time *** European space heritage usable for both the front ends and the antenna technology of such an instrument is *** and future sensors for the required inter-satellite metrology are *** performance estimates and simulation results are given.

关键词： Instrumentation space VLBI Radio Telescopes

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通过原子力显微镜(AFM)对HD DVD压模进行分析

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记录媒体技术 2005年第6期 30-33页

作者： Donald A.Chernoff David L.Burkhead Dick Verhaar Ton van de vorst Advanced surface Microscopy公司 singulus Mastering公司

众所周知,HD DVD和Blu-ray Disc同属于第三代光存储产品。和第一、二代光存储产品——CD光盘和DVD光盘相比,HD DVD和Blu-ray Disc光盘中的特征结构更小,对误差的公差容量也更小。例如,HD DVD光盘的结构中,平均道间距一般为400±10nm(... 详细信息

众所周知,HD DVD和Blu-ray Disc同属于第三代光存储产品。和第一、二代光存储产品——CD光盘和DVD光盘相比,HD DVD和Blu-ray Disc光盘中的特征结构更小,对误差的公差容量也更小。例如,HD DVD光盘的结构中,平均道间距一般为400±10nm(复制盘上),而对单独一张盘片而言。

关键词：原子力显微镜 AFM HD DVD 光存储产品盘片第三代母盘玻璃基片光刻胶截面轮廓

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Evolution and advances in laparoscopic ventral and incisional hernia repair

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World Journal of Gastrointestinal surgery 2015年第11期7卷 293-305页

作者： Alan L vorst Christodoulos Kaoutzanis Alfredo M Carbonell Michael G Franz department of surgery Saint Joseph Mercy Health System department of surgery Greenville Health System University of South Carolina School of Medicine-Greenville

Primary ventral hernias and ventral incisional hernias have been a challenge for surgeons throughout the ages. In the current era, incisional hernias have increased in prevalence due to the very high number of laparotomies performed in the 20 th century. Even though minimally invasive surgery and hernia repair have evolved rapidly, general surgeons have yet to develop the ideal, standardized method that adequately decreases common postoperative complications, such as wound failure, hernia recurrence and pain. The evolution of laparoscopy and ventral hernia repair will be reviewed, from the rectoscopy of the 4th century to the advent of laparoscopy, from suture repair to the evolution of mesh reinforcement. The nuances of minimally invasive ventral and incisional hernia repair will be summarized, from preoperative considerations to variations in intraoperative practice. New techniques have become increasingly popular, such as primary defect closure, retrorectus mesh placement, and concomitant component separation. The advent of robotics has made some of these repairs more feasible, but only time and well-designed clinical studies will tell if this will be a durable modality for ventral and incisional hernia repair.

关键词： Evolution Advances Laparoscopic ventral hernia rep

Near-infrared fluorescence imaging of a solitary fibrous tumor of the pancreas using methylene blue

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World Journal of Gastrointestinal surgery 2012年第7期4卷 180-184页

作者： Joost R van der vorst Alexander L Vahrmeijer Merlijn Hutteman Tjalling Bosse Vincent THBM smit Cornelis JH van de Velde John V Frangioni Bert A Bonsing department of surgery Leiden University Medical CenterAlbinusdreef 22300 RC Leiden The Netherlands department of Pathology Leiden University Medical CenterAlbinusdreef 22300 RC LeidenThe Netherlands department of Medicine Beth Israel Deaconess Medical Center330 Brookline AvenueBostonMA 02215United States

A 67-year-old female presented with unexplained abdominal pain. A contrast-enhanced computed tomography scan of the abdomen incidentally revealed a mass in the uncinate process of the pancreas. This mass was resected and based on histopathological findings, diagnosed as a solitary fibrous tumor (sFT) of the pancreas. A sFT is an extremely rare benign mesenchymal tumor that in 65% of cases affects the visceral pleura but can also affect extra-pleural sites. The intraoperative demarcation of pancreatic tumors, such as sFTs, can bechallenging. In this report, the first clear intraoperative identification of a sFT of the pancreas in a human was shown using near-infrared fluorescence and methylene blue.

关键词： Pancreatic solitary fibrous tumor Near-in-frared fluorescence Image-guided surgery Methylene blue

处境不利青少年参与校外社会情感学习项目的收益——回顾性分析

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中国校外教育 2022年第6期 111-125页

作者：罗谢尔·赫尔姆斯鲁本·福肯克基斯·范·德里尔哈里·沃斯特哈里·沃斯特管奕欣(译) 张欣蕾(译) 曲颖(译) 赵静洁(译) 胡多娇(译) 范家尧(译) Amsterdam University of Applied sciences Amsterdam University of Applied sciences&University of Amsterdam IMC Weekendschool PsI Testuitgevers 华东理工大学中国儿童中心科研部上海外国语大学英语学院

尽管有研究表明,校外项目可对青少年的社会情感学习产生持久的积极效果,但很少有研究进行回顾性分析探索其收益。本研究基于194名校友(年龄15~30岁)的回顾性描述,评估了完成为期3年的周末学校项目(面向荷兰10~14岁的学生)后,学生在社会... 详细信息

尽管有研究表明,校外项目可对青少年的社会情感学习产生持久的积极效果,但很少有研究进行回顾性分析探索其收益。本研究基于194名校友(年龄15~30岁)的回顾性描述,评估了完成为期3年的周末学校项目(面向荷兰10~14岁的学生)后,学生在社会情感学习不同维度上自我感知的收益。这些校友在完成项目后对感知到的收益进行了积极回顾。线性混合模型的结果表明,与居住于郊区的校友相比,居住于城市的校友报告的自我管理、自我意识和未来展望水平更高。与在其他类型学校接受教育的校友相比,接受中等预备职业教育的学生对项目经历的态度明显更积极。在参加后续的全国项目时,这些校友对社会情感学习各个维度的自我感知收益都有更积极的评价。

关键词：校外项目社会情感学习青少年发展回顾性研究城市教育贫困、风险学生处境不利学生社区 10~14岁年龄组

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