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Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas f.Sadreev Yong Li Andrey e.Miroshnichenko School of Physics and electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical engineering Rowan University School of engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are pe.f.ctly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is pe.f.ctly explained by the two-and three-level approximations of the e.f.ctive nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

横形腹直肌肌皮瓣再造术后常规乳腺×线普查探查不能触及的复发性乳腺癌

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国际医学放射学杂志 2008年第5期31卷 398-398页

作者： J.M. Lee D. Georgian-Smith G.S. Gazelle e.f. halpern e.A. Rafferty R.H. Moore 秦乃姗（译）唐光健（校） Department of Radiology Massachusetts General Haspital 101 Merrimac St 10th Floor Boston MA 02114 USA. 不详

目的通过回顾性队列研究确定召回率及肿瘤检出率，从而建立一个决策分析模型来评价横形腹直肌肌皮（TRAM）皮瓣再造术后常规乳腺X线普查的效果。方法本研究经机构审查委员会同意，方法符合HIPAA条例。回顾陛查找医院内乳腺X线摄影结果... 详细信息

目的通过回顾性队列研究确定召回率及肿瘤检出率，从而建立一个决策分析模型来评价横形腹直肌肌皮（TRAM）皮瓣再造术后常规乳腺X线普查的效果。方法本研究经机构审查委员会同意，方法符合HIPAA条例。回顾陛查找医院内乳腺X线摄影结果的数据库，选择1999年1月1日-2005年7月15日间双侧乳腺X线普查的数据。检索词包括“TRAM”；之后查找召回及肿瘤检出率。随后建立决策分析模型，来评价TRAM皮瓣再造术后女性的假定队列。结果554个乳腺X线摄影（265例TRAM皮瓣再造术）中，546个（98．6％）为阴性结果（乳腺影像报告和数据系统分级为1或2级），8个（1．4％）为阳性结果（乳腺影像报告和数据系统分级为0、3、4或5级）。所有可疑病灶均进行了活检，

关键词：横形腹直肌肌皮瓣复发性乳腺癌乳腺X线普查再造术 TRAM皮瓣乳腺X线摄影队列研究决策分析

棕色脂肪的PeT/CT表现及与病人特征的相关性

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国际医学放射学杂志 2012年第4期 388-388页

作者： C.G. Cronin P. Prakash G.H. Daniels G.W. Boland M.K. Kalra e.f. halpern 唐光健 Department of Abdominal Imaging and Interventional Radiology Massachusetts General Hospital55 Fruit St White 270 Boston MA 02114 USA

摘要目的评价癌肿病人棕色脂肪的出现率,对照有与无棕色脂肪病人的人口学特征,并评价这些特征与棕色脂肪平均和最大标准化摄取值的相关性。材料与方法此回顾性研究由学院审查委员会批准,符合HIPAA要求,免除知情同意通知。复习2004年1月-... 详细信息

摘要目的评价癌肿病人棕色脂肪的出现率,对照有与无棕色脂肪病人的人口学特征,并评价这些特征与棕色脂肪平均和最大标准化摄取值的相关性。材料与方法此回顾性研究由学院审查委员会批准,符合HIPAA要求,免除知情同意通知。复习2004年1月-2008年11月6867例病人12195次连续

关键词：棕色脂肪出现率 PeT/CT 病人相关性 CT

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为什么动物试验事关重大?

世界社会科学 2003年第2期 111-113页

作者： e.f.保罗,新馨〔美〕

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小说在巴西民族身份建构中的作用

外国文学 1999年第4期 45-47+51页

作者：Ｅ.Ｆ.库庭霍南京师范大学

不管文学话语和民族身份之间的关联看似多么自然和必然，这种关联还只是一种相对新近的历史建构。民族文学的观念发端于１８世纪与１９世纪的交替时期，特别来源于德国的浪漫主义民族主义者。他们认为文学附属于民族，理应体现民族特征... 详细信息

不管文学话语和民族身份之间的关联看似多么自然和必然，这种关联还只是一种相对新近的历史建构。民族文学的观念发端于１８世纪与１９世纪的交替时期，特别来源于德国的浪漫主义民族主义者。他们认为文学附属于民族，理应体现民族特征。文学民族主义者的根本前提是：人类...

关键词：身份建构魔鬼荒原小说民族权利主体文学话语印第安人文学经典反英雄巴西南美洲印第安主义

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解惑

解惑

Nonlinear Propagation of Positron-Acoustic Periodic Travelling Waves in a Magnetoplasma with Superthermal electrons and Positrons

作者： (英)e.f. 舒马赫(e.f. Schumacher)

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Chinese Physics Letters 2017年第6期34卷 70-74页

作者： e.f.eL-Shamy Department of Physics College of ScienceKing Khalid University Department of Physics Faculty of ScienceDamietta University

The nonlinear propagation of positron acoustic periodic （PAP） travelling waves in a magnetoplasma composed of dynamic cold positrons, superthermal kappa distributed hot positrons and electrons, and stationary positive ions is examined. The reductive perturbation technique is employed to derive a nonlinear Zakharov Kuznetsov equation that governs the essential features of nonlinear PAP travelling waves. Moreover, the bifurcation theory is used to investigate the propagation of nonlinear PAP periodic travelling wave solutions. It is found that kappa distributed hot positrons and electrons provide only the possibility of existence of nonlinear compressive PAP travelling waves. It is observed that the superthermality of hot positrons, the concentrations of superthermal electrons and positrons, the positron cyclotron frequency, the direction cosines of wave vector k along the z-axis, and the concentration of ions play pivotal roles in the nonlinear propagation of PAP travelling waves. Tile present investigation may be used to understand the.f.rmation of PAP structures in the space and laboratory plasmas with superthermal hot positrons and electrons.

关键词： Nonlinear Propagation of Positron-Acoustic Periodic Travelling Waves in a Magnetoplasma with Superthermal electrons and Positrons

Wavevector filtering through Monolayer and Bilayer Graphene Superlattices

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Chinese Physics Letters 2013年第9期30卷 132-135页

作者： f.Sattari e.f.izabadi School of Physics Iran University of Science and Technology16844 TehranIran

We investigate the transport properties through monolayer and bilayer graphene superlattices modulated by an in-plane homogeneous electric field based on the transfer matrix *** is found that the angular range of the transmission probability through a graphene superlattice can be e.f.ctively controlled by the number of barriers and this results in the structure having e.f.cient wavevector *** the number of barriers increases,this range *** is also shown that the conductance of the systems has an oscillatory behavior with respect to the barrier height and it decreases with the increasing number of barriers.

关键词： method. monolayer oscillatory

faddeev calculations on lambda hypertriton with potentials from Gel'fand–Levitan–Marchenko theory

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Communications in Theoretical Physics 2020年第10期72卷 119-124页

作者： e.f.Meoto M L Lekala Department of Physics University of South AfricaPrivate Bag X61710 JohannesburgSouth Africa

e.f.ctive lambda-proton and lambda-neutron potentials,restored from theoretical scattering phases through Gel'fand–Levitan–Marchenko theory,are tested on a lambda hypertriton through three-body *** lambda hypertriton is treated as a three-body system consisting of lambda-proton,lambda-neutron and proton–neutron *** energy and root mean square radius are computed for the ground state of lambda hypertriton(Jp=12+).In coordinate space,the dynamics of the system is described using a set of coupled hyperradial equations obtained from the differential faddeev *** solving the eigenvalue problem derived from this set of coupled hyperradial equations,the binding energy and root mean square matter radius computed are.f.und to be-2.462 MeV and 7.00 fm,*** potentials are also shown to display a satisfactory convergence behaviour.

关键词： lambda-nucleon potential lambda-proton potential lambda-neutron potential lambda hypertriton faddeev equations hyperspherical method