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肾细胞癌:动态对比增强mRI区分肿瘤亚型与病理学对照

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国际医学放射学杂志 2009年第3期 280-280页

作者： L.ngo E.m.Genega m.B.Atkins m.E.Finn n.m.rofsky 陈翔宇 Department of Radiology Beth Israel Deaconess Medical Center330 Brookline AveBostonMA 02215USA

目的回顾分析经病理证实的透明细胞癌、乳头状癌和嫌色细胞癌的动态对比增强mRI强化类型,评估其能否准确地诊断肾细胞癌的亚型。方法本研究得到伦理委员会的批准,并符合HIPAA,未获病人书面同意。112例病人(男76例,女36例,年龄25～88岁,... 详细信息

目的回顾分析经病理证实的透明细胞癌、乳头状癌和嫌色细胞癌的动态对比增强mRI强化类型,评估其能否准确地诊断肾细胞癌的亚型。方法本研究得到伦理委员会的批准,并符合HIPAA,未获病人书面同意。112例病人(男76例,女36例,年龄25～88岁,平均年龄58.1岁),共113个肾肿块(平均直径5.4cm),其中透明细胞型75个,乳头型28个,嫌色细胞型10个。采用1.5T mR设备,行平扫和静脉注射对比剂增强扫描(含皮髓质期与实质期)。

关键词：肾细胞癌乳头状癌皮髓质实质期嫌色细胞动态对比增强亚型 mRI

肾功能损害肾脏肿瘤病人的动脉自旋标记mRI特性:初步经验

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国际医学放射学杂志 2012年第2期 204-204页

作者： I.Pedrosa K.Rafatzand P.Robson A.A.Wagner m.B.Atkins n.m.rofsky 李华兵 Department of Radiology Beth Israel Deaconess Medical Center and Harvard Medical School330 Brookline AveBostonMA02215USA

目的回顾性评价动脉自旋标记(ASL)mRI对肾功能损害病人的肾脏肿瘤血管评估的可行性。方法 2007年5月—2008年11月,对67例中的11例因中度至重度慢性或急性肾功能衰竭的连续病人行未增强ASL-mRI检查,以评

关键词： mRI 肾肿瘤灌注肾功能不全肾源性系统性纤维化

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超低射频功率下颅脑mR成像

国际医学放射学杂志 2011年第4期 380-380页

作者： S.n.Sarkar D.C.Alsop A.J.madhuranthakam R.F.Busse P.m.Robson n.m.rofsky 丁晓辉 Department of Radiology Beth Israel Deaconess Medical CenterHarvard Medical School Applied Science Laboratory GE Healthcare

目的为了探明1.5T颅脑mR成像在保有高射频能量吸收率(SAR)成像具有的组织信号和对比度前提下SAR的底限,以求创立一种切实可用的、超低射频能量的mRI方法对含有植入装置的组织进行成像。材料与方法伦理委员会批准了本项符合HIPAA要求的... 详细信息

目的为了探明1.5T颅脑mR成像在保有高射频能量吸收率(SAR)成像具有的组织信号和对比度前提下SAR的底限,以求创立一种切实可用的、超低射频能量的mRI方法对含有植入装置的组织进行成像。材料与方法伦理委员会批准了本项符合HIPAA要求的前瞻性mR研究设

关键词： mR 射频能量颅脑 SAR 权序列

magnetic,dielectric and electrical modulus of Ce^(3+) doped cobalt-magnesium ferrite nanoparticles

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Journal of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： n.m.Basfer Hanaa Almaghamsi Department of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Department College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,dielectric properties and electric modulus of Ce^(3+) substituted cobaltmagnesium(Co_(0.7)mg_(0.3)Ce_(x)Fe_(2-x)O_4)(labeled as CmCF) ferrite nanoparticles were investigated in detail.Saturation magnetization decreases from 50.05 to 34.87 emu/g for further substituting Ce^(3+) ions.meanwhile,coercivity increases from 738.22 Gs for the CmCFO sample to 912.10 Gs for the CmCF2 sample,then decreases monotonically to 762.1 Gs for the CmCF5 sample.The cerium content and particle size play important roles in controlling the magnetization and coercivity of the CmCF nanoparticles.All CmCF nanoferrites are suitable for microwave applications since their high-frequency response ranges from 7.72 to 11.07 GHz.The CmCF nanoferrites' dielectric parameter dispersion exhibits normal behavior.The pristine Co-mg nanoferrite only has ε' value of 28.25,but the nanoferrite mCmF2 has ε' value of365.03,with an enhancing ratio of 1192%.The conduction mechanism of the mCmF nanoferrites was determined by fitting the σ_(ac) results via the Jonscher power law.At 653 K,large polaron tunnelling is thought to be responsible for this conduction process,which is followed by electron barrier hopping at higher temperatures.Cole-Cole diagrams at different temperatures,assuring the contributions of the grains and their boundaries at lower temperatures(653 K) and only the grains at higher temperatures.Based on our results,the CmCF nanoferrites hold magnetic and semiconducting nature,which can be used in magnetic devices and dielectrics in lower-frequencies or conductors in higher-frequencies.

关键词： nanoferrites Rare earth ions magnetic properties Dielectric parameters Impedance spectroscopy

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EDSUCh:A robust ensemble data summarization method for effective medical diagnosis

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Digital Communications and networks 2024年第1期10卷 182-189页

作者： mohiuddin Ahmed A.n.m.Bazlur Rashid School of Science Edith Cowan UniversityPerthAustralia

Identifying rare patterns for medical diagnosis is a challenging task due to heterogeneity and the volume of data.Data summarization can create a concise version of the original data that can be used for effective diagnosis.In this paper,we propose an ensemble summarization method that combines clustering and sampling to create a summary of the original data to ensure the inclusion of rare patterns.To the best of our knowledge,there has been no such technique available to augment the performance of anomaly detection techniques and simultaneously increase the efficiency of medical diagnosis.The performance of popular anomaly detection algorithms increases significantly in terms of accuracy and computational complexity when the summaries are used.Therefore,the medical diagnosis becomes more effective,and our experimental results reflect that the combination of the proposed summarization scheme and all underlying algorithms used in this paper outperforms the most popular anomaly detection techniques.

关键词： Data summarization Ensemble medical diagnosis Sampling

A FLEXIBLE OBJECTIVE-COnSTRAInT APPROACH AnD A nEW ALGORITHm FOR COnSTRUCTInG THE PARETO FROnT OF mULTIOBJECTIVE OPTImIZATIOn PROBLEmS

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Acta mathematica Scientia 2024年第2期44卷 702-720页

作者： n.HOSEInPOOR m.GHAZnAVI Faculty of mathematical Sciences Shahrood University of TechnologyShahroodIran

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems.

关键词： multiobjective optimization Pareto front scalarization objective-constraint approach proper efficient solution

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Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

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matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt m.Gyrdymov S.Zähter P.Tavana m.m.Günther n.Bukharskii n.Borisenko J.Jacoby X.F.Shen A.Pukhov n.E.Andreev O.n.Rosmej Faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany Focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany national Research nuclear University mEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 meV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an FWHm of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical