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Inverse Class-AB功率放大器线性度和效率分析

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微电子学与计算机 2007年第4期24卷 177-182页

作者：周翠 L.C.n.de Vreeed M.P.Van der Heijden 李文宏复旦大学ASIC系统重点实验室上海200433 荷兰delft科技大学高频技术与器件实验室荷兰Eindhoven菲利普研发中心

inverse Class-AB模式可以使功率放大器得到更好的性能,但是传统的教科书中并没有这种模式的理论分析因此有必要从理论上对inverse Class-AB模式进行分析。通过对输出波形傅里叶函数的研究可以得到最大输出电压摆幅以及计算最大功率。通... 详细信息

inverse Class-AB模式可以使功率放大器得到更好的性能,但是传统的教科书中并没有这种模式的理论分析因此有必要从理论上对inverse Class-AB模式进行分析。通过对输出波形傅里叶函数的研究可以得到最大输出电压摆幅以及计算最大功率。通过Volterra序列分析法以out-of-band抵消技术我们分析这种模式功率放大器的非线性。最后我们进行了大量的仿真以验证所提出的理论。

关键词： inverse C1ass—AB 线性度效率功率输出能力 out—of-band抵消技术

Altitudinal analysis of carbon stocks in the Antisana páramo,Ecuadorian Andes

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Journal of Plant Ecology 2016年第5期9卷 553-563页

作者： Verónica Minaya Gerald Corzo Hugo Romero-Saltos Johannes van der Kwast Egbert Lan.inga Remigio Galárraga-Sánchez Arthur Mynett UnESCO-IHE Institute for Water Education Westvest 72611 AX DelftThe Netherlands Technological University of Delft-TU-Delft Stevinweg 12628 CN DelftThe Netherlands Escuela Politécnica nacional EPNWater Science UnitLadrón de Guevara E11-253Quito 170517Ecuador Yachay Tech Ciudad del Conocimiento YachayHacienda San JoséS/NSan Miguel de Urcuquí100119Ecuador Farming Systems Ecology Wageningen UniversityPO Box 5636700 AN WageningenThe Netherlands

Aims The importance of quantifying carbon stocks in terrestrial ecosystems is crucial for determining climate change ***,the present regional assessments of carbon stocks in tropical grasslands are extrapolated to unsampled areas with a high degree of uncertainty and without considering the carbon and nitrogen composition of vegetation and soil along altitudinal *** study aims to assess carbon and nitrogen concentrations in soil and vegetation,aboveground carbon stocks distribution and soil organic carbon stocks along an altitudinal range in the páramo region.in the Ecuadorian *** The vegetation.inventory was conducted using 15×15 m sampling plots distributed in three altitudinal *** on the patterns exhibited by the dominant vegetation growth forms,biomass and soil were sampled to quantify the correspon.ing carbon and nitrogen ***,the aboveground live biomass along the páramo altitudinal range was estimated using allometric ***,soil and vegetation carbon stocks were estimated for the entire *** Fin.ings Altitudinal analysis supported a potential distribution of carbon and nitrogen concentrations in soil,litter and live tissues,where higher concentrations were found in the low altitudinal range mainly for tussocks and acaulescent *** in litter showed higher concentrations at low altitudinal ranges for acaulescent rosettes and cushions *** the same growth forms,lignin patterns in litter were higher in high altitudinal *** texture provided complementary information:high percentage of silt was highly correlated to high soil nitrogen and carbon *** were found to be responsive to altitude with their,highest aboveground carbon stocks occurring at the low altitudinal range,but cushions and acaulescent rosettes responded *** established relationships among soil,vegetation and altitude shown.in this study must be taken.into accou

关键词： Andes carbon growth forms nitrogen páramo grassland

Safety and biodegradability of a synthetic dural sealant patch(Liqoseal)in a porcine cranial model

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Animal Models and Experimental Medicine 2021年第4期4卷 398-405页

作者： Ahmet Kinaci Wilhelmina Bergmann Sander van Thoor Saskia Redegeld Albert van der Zwan Tristan P.C.van Doormaal Department of neurology and neurosurgery Brain CenterUniversity Medical Centre UtrechtUtrechtThe Netherlands Brain Technology Institute UtrechtThe Netherlands Division of Pathology Faculty of Veterinary MedicineUtrecht UniversityUtrechtThe Netherlands Department of neurosurgery Clinical Neuroscience CenterUniversity Hospital ZurichZurichSwitzerland

Background:Liqoseal consists of a watertight layer of poly(ester)ether urethane and an adhesive layer containing polyethylene glycol-n-hydroxysuccinimide(PEG-nHS).It is designed to prevent cerebrospinal fluid(CSF)leakage after intradural *** study assessed the safety and biodegradability of Liqoseal in a porcine craniotomy ***:In 32 pigs a craniotomy plus durotomy was *** 15 pigs Liqoseal was implanted,in 11 control pigs no sealant was implanted and in 6 control pigs a control dural sealant(Duraseal or Tachosil)was *** safety of Liqoseal was evaluated by clinical,MRI and histological *** degradation of Liqoseal was histologically ***:Liqoseal,2 mm thick before application,did not swell and significantly was at maximum mean thickness of 2.14(±0.37)mm at one *** foreign body reaction.induced by Liqoseal,Duraseal and Tachosil were *** showed no adherence to the arachnoid layer and was completely resorbed between 6 and 12 months *** one animal with Liqoseal,an epidural fluid collection containing CSF could not be ***:Liqoseal seems to be safe for intracranial use and is *** safety and performance in humans needs to be further assessed in clinical trials.

关键词： cerebrospinal fluid leakage craniotomy dura in vivo model sealant

Risk of critical limb ischemia in long-term uterine cancer survivors:A population-based study

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World Journal of Clinical Cases 2022年第36期10卷 13293-13303页

作者： Min-Chi Chen Jung-Jung Chang Miao-Fen Chen Ting-Yao Wang Cih-En Huang Kuan-der Lee Chao-Yu Chen Department of Public Health Chang Gung UniversityTaoyuan 333Taiwan Department of Obstetrics and Gynecology Chang Gung Memorial HospitalChiayi 612Taiwan Division of Cardiovascular Disease Department of Internal MedicineChang Gung Memorial HospitalChiayi 612Taiwan Department of Radiation Oncology Change Gung Memorial HospitalLinkouTaoyuan 333Taiwan Division of Hematology and Oncology Department of Internal MedicineChang Gung Memorial HospitalChiayi 612Taiwan Graduate Institute of Clinical Medical Sciences College of MedicineChang Gung UniversityTaoyuan 333Taiwan Department of Medicine Taipei Medical University HospitalTaipei 100Taiwan Department of Medical Research Taichung Veterans General HospitalTaichung 407Taiwan Department of Post-Baccalaureate Medicine College of MedicineNational Chung Hsing UniversityTaichung 402Taiwan Department of Early Childhood Care and Education Shu-Zen Junior College of Medicine and ManagementKaohsiung 821Taiwan

BACKGROUnD The risk of critical limb ischemia(CLI)which causes ischemic pain or ischemic loss in the arteries of the lower extremities in long-term uterine cancer(UC)survivors remains unclear,especially in Asian patients,who are younger at the diagnosis of UC than their Western *** To conduct a nationwide population-based study to assess the risk of CLI in UC long-term *** UC survivors,defined as those who survived for longer than 5 years after the diagnosis,were identified and matched at a 1:4 ratio with normal *** Cox models were used to assess the risk of *** From 2000 to 2005,1889 UC survivors who received surgery alone or surgery combined with radiotherapy(RT)were classified into younger(onset agen=894)and older(onset age≥50 years,n=995)*** compared with normal controls,the younger patients with diabetes,hypertension,and receiving hormone replacement therapy(HRT)were more likely to develop *** contrast,the risk of CLI was associated with adjuvant RT,obesity,hypertension,and HRT in the older *** the UC survivors,those who were diagnosed at an advanced age(>65 years,aHR=2.48,P=0.011),had hypertension(aHR=2.18,P=0.008)or received HRT(aHR=3.52,P=0.020)were at a higher risk of *** In this nationwide study,we found that the risk factors associated with CLI were similar in both cohorts except for adjuvant RT that was negligible in the younger group,but positive in the older *** the survivors,hypertension,advanced age,and HRT were more hazardous than *** prevention should include CLI as a late complication.in UC survivorship programs.

关键词： Uterine cancer Critical limb ischemia Radiotherapy Survivorship

中国大陆及邻区Rayleigh面波相速度分布特征

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地球物理学报 2008年第2期51卷 402-411页

作者：易桂喜姚华建朱介寿 Robert D．van der Hilst 成都理工大学成都610059 四川省地震局成都610041 Massachusetts Institute of Technology CambridgeMassachusetts 02139USA

本文根据102个数字化台站记录的长周期垂直向面波资料,利用双台互相关方法测量了538条独立路径的基阶Rayleigh面波相速度频散资料,反演获得了中国大陆及边邻地区(70°E^140°E,18°n^55°n)20~120s(周期间隔为5s)共21个周期的Rayleigh... 详细信息

本文根据102个数字化台站记录的长周期垂直向面波资料,利用双台互相关方法测量了538条独立路径的基阶Rayleigh面波相速度频散资料,反演获得了中国大陆及边邻地区(70°E^140°E,18°n^55°n)20~120s(周期间隔为5s)共21个周期的Rayleigh波相速度空间分布图像.检测板测试结果显示中国大陆中东部地区横向分辨率可达3°,而西部及边邻地区大约5°.研究表明,中国大陆地区的Rayleigh波相速度分布横向差异显著,大致以104°E为界,可分成具有不同速度结构特征的东、西两部分.一般较短周期(20~35s)的相速度分布受地形和地壳厚度的影响较大,总体表现为东部速度高,西部速度低;塔里木盆地、青藏地块及其东缘的松潘-甘孜地块形成整个研究区内最为突出的低速异常体,蒙古西部低速特征也较清晰;东部的四川盆地、扬子地块、华南地块、松辽盆地、日本海及蒙古东部高速特征明显.随着周期的增大,青藏地块中部的低速异常体横向尺度逐渐缩小,而喜马拉雅冲断带、塔里木盆地相速度不断升高,意味着青藏低速区受到南、西北、东三个方向的高速区夹击,可能导致高原中部软弱的低速物质向东南方向迁移;同时,东部地区由高速逐渐转变为大面积的低速分布,反映东部地区岩石圈较薄而软流圈发育.随着青藏地块低速特征的减弱,印支地块北部及相邻海域、东海、东北吉林深震区、日本海、中-朝地块至蒙古东部成为120s周期上突出的低速异常体,而上扬子地块包括四川盆地高速特征依然明显,显示出稳定的古板块特征.南北地震带始终呈现出相对较低的速度特征,并成为划分中国大陆具有不同岩石圈相速度特征的东部与西部的天然分界.

关键词： Rayleigh面波相速度分布双台法中国大陆

new Metathesis Polymers via Ring-Opening Metathesis Polymerization （ROMP）

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Follow-up in patients with a burn-related emergency department visit:a feasibility study

2006年海峡两岸高分子学术研讨会

作者： der-Jang Liaw Department of Chemical En.ineering National Taiwan University of Science and Technology43Keelung RoadSection 4Taipei 106

＜正＞The, 5-（phthalimide methyl）bicyclo[2.2.1]hept-2-ene （endo rich nBMPI）, 5-（n-carbazoyl methyl）bicyclo[2.2.1]hept-2-ene （endo rich nBCbz） and exo-5-（fluorene carboxyl methyl） bicyclo[2.2.1]hept-2-ene （exo nBF） were successfully synthesized and their polymers also were prepared via living ring-opening metathesis polymerization （ROMP）（Scheme Ⅰ）. Remarkable differences of reactivity and polymerization behavior of active norbornenes depend on molecular architectures having pendant amide or ester groups. Polynorbornenes derived from active norbornenes with ethylene between urethane group and ester group showed excellent solubility because of disturbance of hydrogen bon.ing [poly（1a-1c）, Scheme Ⅱ]. Organosoluble polymer could be obtained by modification of polymerization technique such as ligand exchange, random copolymerization, and chan.ing the molar ratio of monomer to catalyst （Scheme Ⅱ）. The molecular weight of the polymers could be controlled and polydispersity was narrow. Organo-soluble comb-shaped copolymers with MMA could be synthesized using atom transfer radical polymerization （ATRP） macroinitiator [poly（HnBBrMPAM）] in diluted macroinitiator solution with a concentration less than 3.64×10-2 mol·L-1[Scheme Ⅲ（A） and （B）]. Star-like polynorbornene [poly（nBPMMA）] with high cis microstructure （cis/trans=72/28） was obtained directly by ROMP of nBPMMA macromonomer （Mn= 6.4×103） [Scheme （C）].

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来源： cnki会议评论

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Burns & Trauma 2017年第4期5卷 260-267页

作者： H. Goei B. F. M. Wijnen S. Mans M. A. C. de Jongh C. H. van der Vlies S. Polinder n. E. E. van Loey M. E. van Baar Association of Dutch Burn Centres Burn Centre Maasstad Hospital PO Box 9100 3007 AC Rotterdam the Netherlands Department of Plastic Reconstructive and Hand Surgery MOVE Research Institute VU University Medical Centre Amsterdam the Netherlands Association of Dutch Burn Centres Burn Centre Maasstad Hospital PO Box 9100 3007 AC Rotterdam the Netherlands Department of Health Services Research CAPHRI School of Public Health and Primary Care Maastricht University 6200 MD Maastricht the Netherlands Trauma Centre Brabant Elisabeth-TweeSteden Hospital Tilburg the Netherlands Burn Centre Maasstad Hospital Rotterdam the Netherlands Department of Public Health Erasmus Medical Centre Rotterdam the Netherlands Association of Dutch Burn Centres Red Cross Hospital Beverwijk the Netherlands Association of Dutch Burn Centres Burn Centre Maasstad Hospital PO Box 9100 3007 AC Rotterdam the Netherlands Department of Public Health Erasmus Medical Centre Rotterdam the Netherlands

Background:Data on epidemiology, costs, and outcomes of burn-related injuries presen.ing at emergency departments (EDs) are scarce. To obtain such information, a questionnaire study with an adequate response rate is imperative. There is evidence that optimized strategies can.increase patient participation. However, it is unclear whether this applies to burn patients in an ED setting. The objective of this feasibility study was to optimize and evaluate patient recruitment strategy and follow-up methods in patients with burn.injuries presen.ing at EDs. Methods:In a prospective cohort study with a 6-month follow-up, patients with burn-related injuries atten.ing two large EDs during a 3-month study period were included. Eligible patients were quasi-randomly allocated to a standard or optimized recruitment strategy by week of the ED visit. The standard recruitment strategy consisted of an.invitation letter to participate, an.informed consent form, a questionnaire, and a franked return envelope. The optimized recruitment strategy was complemented by a stamped returned envelope, monetary incentive, sen.ing a second copy of the questionnaire, and a reminder by telephone in non-responders. Response rates were calculated, and questionnaires were used to assess treatment, costs, and health-related quality of life. Results:A total of 87 patients were included of which 85 were eligible for the follow-up study. There was a higher response rate at 2 months in the optimized versus the standard recruitment strategy (43.6%vs. 20.0%;OR=3.1 (95%CI 1.1–8.8)), although overall response is low. non-response analyses showed no significant differences in patient, burn.injury or treatment characteristics between responders versus non-responders. Conclusions:This study demonstrated that response rates can be increased with an optimized, but more labor-intensive recruitment strategy, although further optimization of recruitment and follow-up is needed. It is feasible to assess epidemiology, tr

关键词： Burns Emergency department Recruitment strategy Response rate Health care survey methods

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 understan.ing 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

The histopathological spectrum of myocardial inflammation.in relation to circumstance of death:a retrospective cohort study in clinical and forensic autopsies

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Forensic Sciences Research 2022年第2期7卷 238-246页

作者： Romy du Long Judith Fronczek Hans W.M.niessen Allard C.van der Wal Hans H.de Boer Department of Pathology Amsterdam University Medical CenterUniversity of AmsterdamAmsterdamThe Netherlands Department of Forensic Medicine Netherlands Forensic InstituteThe HagueThe Netherlands

Interpreting a myocardial inflammation as causal,contributory or as of no significance at all in the cause of death can be challen.ing,especially in cases where other pathologic and/or medico-legal fin.ings are also *** further evaluate the significance of myocardial inflammation as a cause of death we performed a retrospective cohort study of forensic and clinical autopsy *** revised the spectrum of histological inflammatory parameters in the myocardium of 79 adult autopsy cases and related these to the reported cause of *** slides were reviewed for the distribution and intensity of inflammatory cell infiltrations,the predominant inflammatory cell type,and the presence of inflammation-associated myocyte injury,fibrosis,edema and ***,the cases were divided over three groups,based on the reported cause of *** 1(n=27)consisted of all individuals with an obvious unnatural cause of *** 2(n=29)included all individuals in which myocarditis was interpreted to be one out of more possible causes of *** 3(n=23)consisted of all individuals in which myocarditis was reported to be the only significant fin.ing at autopsy,and no other cause of death was *** application of our histological parameters showed that only a diffuse increase of inflammatory cells could discriminate between an.incidental presence of inflammation(Group 1)or a potentially significant one(Groups 2 and 3).no other histological parameter showed significant differences between the *** results suggest that generally used histological parameters are often.insufficient to differentiate an.incidental myocarditis from a(potentially)significant one.

关键词： Forensic sciences myocarditis myocardial inflammation diagnosis forensic pathology cause of death autopsy pathology