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Interplay between the glymphatic system and neurotoxic proteins in Parkinson’s disease and related disorders:current knowledge and future directions 被引量:1
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作者 Yumei Yue Xiaodan Zhang +2 位作者 Wen Lv Hsin-Yi Lai Ting Shen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期1973-1980,共8页
Parkinson’s disease is a common neurodegenerative disorder that is associated with abnormal aggregation and accumulation of neurotoxic proteins,includingα-synuclein,amyloid-β,and tau,in addition to the impaired eli... Parkinson’s disease is a common neurodegenerative disorder that is associated with abnormal aggregation and accumulation of neurotoxic proteins,includingα-synuclein,amyloid-β,and tau,in addition to the impaired elimination of these neurotoxic protein.Atypical parkinsonism,which has the same clinical presentation and neuropathology as Parkinson’s disease,expands the disease landscape within the continuum of Parkinson’s disease and related disorders.The glymphatic system is a waste clearance system in the brain,which is responsible for eliminating the neurotoxic proteins from the interstitial fluid.Impairment of the glymphatic system has been proposed as a significant contributor to the development and progression of neurodegenerative disease,as it exacerbates the aggregation of neurotoxic proteins and deteriorates neuronal damage.Therefore,impairment of the glymphatic system could be considered as the final common pathway to neurodegeneration.Previous evidence has provided initial insights into the potential effect of the impaired glymphatic system on Parkinson’s disease and related disorders;however,many unanswered questions remain.This review aims to provide a comprehensive summary of the growing literature on the glymphatic system in Parkinson’s disease and related disorders.The focus of this review is on identifying the manifestations and mechanisms of interplay between the glymphatic system and neurotoxic proteins,including loss of polarization of aquaporin-4 in astrocytic endfeet,sleep and circadian rhythms,neuroinflammation,astrogliosis,and gliosis.This review further delves into the underlying pathophysiology of the glymphatic system in Parkinson’s disease and related disorders,and the potential implications of targeting the glymphatic system as a novel and promising therapeutic strategy. 展开更多
关键词 atypical parkinsonism glymphatic system magnetic resonance imaging neurotoxic proteins Parkinson’s disease
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Resonantly enhanced second-and third-harmonic generation in dielectric nonlinear metasurfaces 被引量:1
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作者 Ji Tong Wang Pavel Tonkaev +5 位作者 Kirill Koshelev Fangxing Lai Sergey Kruk Qinghai Song Yuri Kivshar Nicolae C.Panoiu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第5期5-19,共15页
Nonlinear dielectric metasurfaces provide a promising approach to control and manipulate frequency conversion optical processes at the nanoscale,thus facilitating both advances in fundamental research and the developm... Nonlinear dielectric metasurfaces provide a promising approach to control and manipulate frequency conversion optical processes at the nanoscale,thus facilitating both advances in fundamental research and the development of new practical applications in photonics,lasing,and sensing.Here,we employ symmetry-broken metasurfaces made of centrosymmetric amorphous silicon for resonantly enhanced second-and third-order nonlinear optical response.Exploiting the rich physics of optical quasi-bound states in the continuum and guided mode resonances,we comprehensively study through rigorous numerical calculations the relative contribution of surface and bulk effects to second-harmonic generation(SHG)and the bulk contribution to third-harmonic generation(THG) from the meta-atoms.Next,we experimentally achieve optical resonances with high quality factors,which greatly boosts light-matter interaction,resulting in about 550 times SHG enhancement and nearly 5000-fold increase of THG.A good agreement between theoretical predictions and experimental measurements is observed.To gain deeper insights into the physics of the investigated nonlinear optical processes,we further numerically study the relation between nonlinear emission and the structural asymmetry of the metasurface and reveal that the generated harmonic signals arising from linear sharp resonances are highly dependent on the asymmetry of the meta-atoms.Our work suggests a fruitful strategy to enhance the harmonic generation and effectively control different orders of harmonics in all-dielectric metasurfaces,enabling the development of efficient active photonic nanodevices. 展开更多
关键词 second-harmonic generation third-harmonic generation bound state in the continuum guided mode resonance all-dielectric metasurfaces nonlinear optics
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Investigation on the roles of equilibrium toroidal rotation during edge-localized mode mitigated by resonant magnetic perturbations
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作者 董良康 陈少永 +3 位作者 牟茂淋 罗杨 秦晨晨 唐昌建 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期16-33,共18页
The effects of equilibrium toroidal rotation during edge-localized mode(ELM)mitigated by resonant magnetic perturbation(RMP)are studied with the experimental equilibria of the EAST tokamak based on the four-field mode... The effects of equilibrium toroidal rotation during edge-localized mode(ELM)mitigated by resonant magnetic perturbation(RMP)are studied with the experimental equilibria of the EAST tokamak based on the four-field model in the BOUT++code.As the two main parameters to determine the toroidal rotation profiles,the rotation shear and magnitudes were separately scanned to investigate their roles in the impact of RMPs on peeling-ballooning(P-B)modes.On one hand,the results show that strong toroidal rotation shear is favorable for the enhancement of the self-generated E×B shearing rate<ω_(E×B)>with RMPs,leading to significant ELM mitigation with RMP in the stronger toroidal rotation shear region.On the other hand,toroidal rotation magnitudes may affect ELM mitigation by changing the penetration of the RMPs,more precisely the resonant components.RMPs can lead to a reduction in the pedestal energy loss by enhancing the multimode coupling in the turbulence transport phase.The shielding effects on RMPs increase with the toroidal rotation magnitude,leading to the enhancement of the multimode coupling with RMPs to be significantly weakened.Hence,the reduction in pedestal energy loss by RMPs decreased with the rotation magnitude.In brief,the results show that toroidal rotation plays a dual role in ELM mitigation with RMP by changing the shielding effects of plasma by rotation magnitude and affecting<ω_(E×B)>by rotation shear.In the high toroidal rotation region,toroidal rotation shear is usually strong and hence plays a dominant role in the influence of RMP on P-B modes,whereas in the low rotation region,toroidal rotation shear is weak and has negligible impact on P-B modes,and the rotation magnitude plays a dominant role in the influence of RMPs on the P-B modes by changing the field penetration.Therefore,the dual role of toroidal rotation leads to stronger ELM mitigation with RMP,which may be achieved both in the low toroidal rotation region and the relatively high rotation region that has strong rotational shear. 展开更多
关键词 edge-localized mode peeling–ballooning modes resonant magnetic perturbation toroidal rotation plasma response TOKAMAK
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Seismic evaluation of frequency influence and resonant behavior for lead rubber bearing isolated rigid rectangular liquid tanks
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作者 Jyoti Ranjan Barik Kishore Chandra Biswal 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期973-994,共22页
The seismic behavior of a partially filled rigid rectangular liquid tank is investigated under short-and longduration ground motions.A finite element model is developed to analyze the liquid domain by using four-noded... The seismic behavior of a partially filled rigid rectangular liquid tank is investigated under short-and longduration ground motions.A finite element model is developed to analyze the liquid domain by using four-noded quadrilateral elements.The competency of the model is verified with the available results.Parametric studies are conducted for the dynamic parameters of the base-isolated tank,using a lead rubber bearing to evaluate the optimum damping and time period of the isolator.The application of base isolation has reduced the total and impulsive hydrodynamic components of pressure by 80 to 90 percent,and base shear by 15 to 95 percent,depending upon the frequency content and duration of the considered earthquakes.The sloshing amplitude of the base-isolated tank is reduced by 18 to 94 percent for most of the short-duration earthquakes,while it is increased by 17 to 60 percent for the majority of the long-duration earthquakes.Furthermore,resonance studies are carried out through a long-duration harmonic excitation to obtain the dynamic behavior of non-isolated and isolated tanks,using a nonlinear sloshing model.The seismic responses of the base-isolated tank are obtained as higher when the excitation frequency matches the fundamental sloshing frequency rather than the isolator frequency. 展开更多
关键词 lead rubber bearing frequency domain resonant inputs long-duration excitation
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Two Distinct Charge Orders in Infinite-Layer PrNiO_(2+δ) Revealed by Resonant X-Ray Diffraction
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作者 Xiaolin Ren Ronny Sutarto +9 位作者 Qiang Gao Qisi Wang Jiarui Li Yao Wang Tao Xiang Jiangping Hu J.Chang Riccardo Comin X.J.Zhou Zhihai Zhu 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第11期154-169,共16页
Research of infinite-layer nickelates has unveiled a broken translation symmetry,which has sparked significant interest in its root,its relationship to superconductivity,and its comparison to charge order in cuprates.... Research of infinite-layer nickelates has unveiled a broken translation symmetry,which has sparked significant interest in its root,its relationship to superconductivity,and its comparison to charge order in cuprates.In this study,resonant x-ray scattering measurements were performed on thin films of infinite-layer PrNiO_(2+δ).The results show significant differences in the superlattice reflection at the Ni L_(3) absorption edge compared to that at the Pr M_(5) resonance in their dependence on energy,temperature,and local symmetry.These differences point to two distinct charge orders,although they share the same in-plane wavevectors.It is suggested that these dissimilarities could be linked to the excess oxygen dopants,given that the resonant reflections were observed in an incompletely reduced PrNiO_(2+δ)film.Furthermore,azimuthal analysis indicates that the oxygen ligands likely play a crucial role in the charge modulation revealed at the Ni L_(3) resonance. 展开更多
关键词 film. resonant CHARGE
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High-Q resonant terahertz metasurfaces
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作者 Manukumara Manjappa Yuri Kivshar 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第4期1-3,共3页
In photonics, the quest for high-quality (high Q) resonances driven by the physics of bound states in the continuum (BIC)1,2has motivated researchers to explore innovative avenues for realizing groundbreaking applicat... In photonics, the quest for high-quality (high Q) resonances driven by the physics of bound states in the continuum (BIC)1,2has motivated researchers to explore innovative avenues for realizing groundbreaking applications in lasing3, sensing4and nonlinear photonics5. A conventional strategy to harness the properties of BICs involves breaking the symmetry of resonators in a uniform lattice, allowing uncoupled modes to interact with free space that opens a leaky channel in the form of socalled (quasi) q BIC6modes. 展开更多
关键词 BREAKING resonant SYMMETRY
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Effects of asymmetric coupling and boundary on the dynamic behaviors of a random nearest neighbor coupled system
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作者 徐玲 姜磊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期309-322,共14页
This study investigates the dynamical behaviors of nearest neighbor asymmetric coupled systems in a confined space.First, the study derivative analytical stability and synchronization conditions for the asymmetrically... This study investigates the dynamical behaviors of nearest neighbor asymmetric coupled systems in a confined space.First, the study derivative analytical stability and synchronization conditions for the asymmetrically coupled system in an unconfined space, which are then validated through numerical simulations. Simulation results show that asymmetric coupling has a significant impact on synchronization conditions. Moreover, it is observed that irrespective of whether the system is confined, an increase in coupling asymmetry leads to a hastened synchronization pace. Additionally, the study examines the effects of boundaries on the system's collective behaviors via numerical experiments. The presence of boundaries ensures the system's stability and synchronization, and reducing these boundaries can expedite the synchronization process and amplify its effects. Finally, the study reveals that the system's output amplitude exhibits stochastic resonance as the confined boundary size increases. 展开更多
关键词 asymmetric coupled confined space SYNCHRONIZATION stochastic resonance stability
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Polariton lasing in Mie-resonant perovskite nanocavity
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作者 Mikhail A.Masharin Daria Khmelevskaia +12 位作者 Valeriy I.Kondratiev Daria I.Markina Anton D.Utyushev Dmitriy M.Dolgintsev Alexey D.Dmitriev Vanik A.Shahnazaryan Anatoly P.Pushkarev Furkan Isik Ivan V.Iorsh Ivan A.Shelykh Hilmi V.Demir Anton K.Samusev Sergey V.Makarov 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第4期27-42,共16页
Deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the nanoscale.One of the main obstacles for the development of single-particle nanolasers with all three dime... Deeply subwavelength lasers(or nanolasers)are highly demanded for compact on-chip bioimaging and sensing at the nanoscale.One of the main obstacles for the development of single-particle nanolasers with all three dimensions shorter than the emitting wavelength in the visible range is the high lasing thresholds and the resulting overheating.Here we ex-ploit exciton-polariton condensation and mirror-image Mie modes in a cuboid CsPbBr3 nanoparticle to achieve coherent emission at the visible wavelength of around 0.53μm from its ultra-small(≈0.007μm3 or≈λ3/20)semiconductor nanocav-ity.The polaritonic nature of the emission from the nanocavity localized in all three dimensions is proven by direct com-parison with corresponding one-dimensional and two-dimensional waveguiding systems with similar material parameters.Such a deeply subwavelength nanolaser is enabled not only by the high values for exciton binding energy(≈35 meV),re-fractive index(>2.5 at low temperature),and luminescence quantum yield of CsPbBr3,but also by the optimization of po-laritons condensation on the Mie resonances with quality factors improved by the metallic substrate.Moreover,the key parameters for optimal lasing conditions are intermode free spectral range and phonons spectrum in CsPbBr3,which govern polaritons condensation path.Such chemically synthesized colloidal CsPbBr3 nanolasers can be potentially de-posited on arbitrary surfaces,which makes them a versatile tool for integration with various on-chip systems. 展开更多
关键词 nanolaser PEROVSKITE POLARITON Mie resonance EXCITON-POLARITON
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Comparison of transport coefficients before and after density pump-out induced by resonant magnetic perturbation using a BOUT++ six-field model on the EAST tokamak
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作者 邓成成 刘子奚 +22 位作者 夏天阳 刘彦君 厉鹏程 龙飞飞 高翔 王守信 李国强 刘海庆 臧庆 李玖瑛 杨康宁 吴茗甫 尹晓宇 李弘 谢锦林 兰涛 毛文哲 刘阿娣 周楚 丁卫星 庄革 刘万东 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期111-119,共9页
Many experiments have demonstrated that resonant magnetic perturbation(RMP) can affect the turbulent transport at the edge of the tokamak. Through the Experimental Advanced Superconducting Tokamak(EAST) density modula... Many experiments have demonstrated that resonant magnetic perturbation(RMP) can affect the turbulent transport at the edge of the tokamak. Through the Experimental Advanced Superconducting Tokamak(EAST) density modulation experiment, the particle transport coefficients were calculated using the experimental data, and the result shows that the particle transport coefficients increase with RMP. In this study, the six-field two-fluid model in BOUT++ is used to simulate the transport before and after density pump-out induced by RMP,respectively referred as the case without RMP and the case with RMP. In the linear simulations,the instabilities generally decreases for cases with RMP. In the nonlinear simulation, ELM only appears in the case without RMP. Additionally, the particle transport coefficient was analyzed,and the result shows that the particle transport coefficient becomes larger for the case with RMP,which is consistent with the experimental conclusion. Moreover, its magnitude is comparable to the results calculated from experimental data. 展开更多
关键词 BOUT++ resonant magnetic perturbation(RMP) transport coefficients
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Response analysis of NMRG system considering Rb-Xe coupling
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作者 Yi Zhang Qiyuan Jiang +6 位作者 Bingfeng Sun Jiahu Wei Lin Yang Yongyuan Li Zhiguo Wang Kaiyong Yang Hui Luo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期390-402,共13页
The dynamic range of the nuclear magnetic resonance gyroscope can be effectively improved through the closedloop control scheme,which is crucial to its application in inertial measurement.This paper presents the analy... The dynamic range of the nuclear magnetic resonance gyroscope can be effectively improved through the closedloop control scheme,which is crucial to its application in inertial measurement.This paper presents the analytical transfer function of Xe closed-loop system in the nuclear magnetic resonance gyroscope considering Rb–Xe coupling effect.It not only considers the dynamic characteristics of the system more comprehensively,but also adds the influence of the practical filters in the gyro signal processing system,which can obtain the accurate response characteristics of signal frequency and amplitude at the same time.The numerical results are compared with an experimentally verified simulation program,which indicate great agreement.The research results of this paper are of great significance to the practical application and development of the nuclear magnetic resonance gyroscope. 展开更多
关键词 nuclear magnetic resonance gyroscope transfer characteristics Rb-Xe coupling
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Phonon resonance modulation in weak van der Waals heterostructures:Controlling thermal transport in graphene-silicon nanoparticle systems
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作者 李毅 刘一浓 胡世谦 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期96-102,共7页
The drive for efficient thermal management has intensified with the miniaturization of electronic devices.This study explores the modulation of phonon transport within graphene by introducing silicon nanoparticles inf... The drive for efficient thermal management has intensified with the miniaturization of electronic devices.This study explores the modulation of phonon transport within graphene by introducing silicon nanoparticles influenced by van der Waals forces.Our approach involves the application of non-equilibrium molecular dynamics to assess thermal conductivity while varying the interaction strength,leading to a noteworthy reduction in thermal conductivity.Furthermore,we observe a distinct attenuation in length-dependent behavior within the graphene-nanoparticles system.Our exploration combines wave packet simulations with phonon transmission calculations,aligning with a comprehensive analysis of the phonon transport regime to unveil the underlying physical mechanisms at play.Lastly,we conduct transient molecular dynamics simulations to investigate interfacial thermal conductance between the nanoparticles and the graphene,revealing an enhanced thermal boundary conductance.This research not only contributes to our understanding of phonon transport but also opens a new degree of freedom for utilizing van der Waals nanoparticle-induced resonance,offering promising avenues for the modulation of thermal properties in advanced materials and enhancing their performance in various technological applications. 展开更多
关键词 thermal conductivity molecular dynamics phonon resonance van der Waals interaction graphene-silicon nanoparticle heterostructure
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Approximate constructions of counterdiabatic driving with NMR quantum systems
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作者 Hui Zhou Xiaoli Dai +2 位作者 Jianpei Geng Yunlan Ji Xinhua Peng 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期83-91,共9页
Counterdiabatic driving (CD) offers a fast and robust route to manipulate quantum systems, which has widespreadapplications in quantum technologies. However, for higher-dimensional complex systems, the exact CD term i... Counterdiabatic driving (CD) offers a fast and robust route to manipulate quantum systems, which has widespreadapplications in quantum technologies. However, for higher-dimensional complex systems, the exact CD term involving thespectral properties of the system is difficult to calculate and generally takes a complicated form, impeding its experimentalrealization. Recently, many approximate methods have been proposed for designing CD passages in many-body systems. Inthis topical review, we focus on the CD formalism and briefly introduce several experimental constructions and applicationsof approximate CD driving in spin-chain models with nuclear magnetic resonance (NMR) systems. 展开更多
关键词 nuclear magnetic resonance quantum simulation quantum state engineering
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Logical stochastic resonance in a cross-bifurcation non-smooth system
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作者 张宇青 雷佑铭 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期659-667,共9页
This paper investigates logical stochastic resonance(LSR)in a cross-bifurcation non-smooth system driven by Gaussian colored noise.In this system,a bifurcation parameter triggers a transition between monostability,bis... This paper investigates logical stochastic resonance(LSR)in a cross-bifurcation non-smooth system driven by Gaussian colored noise.In this system,a bifurcation parameter triggers a transition between monostability,bistability and tristability.By using Novikov's theorem and the unified colored noise approximation method,the approximate Fokker-Planck equation is obtained.Then we derive the generalized potential function and the transition rates to analyze the LSR phenomenon using numerical simulations.We simulate the logic operation of the system in the bistable and tristable regions respectively.We assess the impact of Gaussian colored noise on the LSR and discover that the reliability of the logic response depends on the noise strength and the bifurcation parameter.Furthermore,it is found that the bistable region has a more extensive parameter range to produce reliable logic operation compared with the tristable region,since the tristable region is more sensitive to noise than the bistable one. 展开更多
关键词 logical stochastic resonance BIFURCATION mean first passage time
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Non-Stationary and Resonant Passage of a System: A High-Frequency Cutoff Noise
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作者 Xiaoyang Shi 《Journal of Modern Physics》 2023年第10期1323-1332,共10页
We study non-equilibrium behaviors of a particle subjected to a high-frequency cutoff noise in terms of generalized Langevin equation, where the spectrum of internal noise is considered to be of the generalized Debye ... We study non-equilibrium behaviors of a particle subjected to a high-frequency cutoff noise in terms of generalized Langevin equation, where the spectrum of internal noise is considered to be of the generalized Debye form. A closed solution is impossible even if the equation is linear, because the Laplace transform of the memory kernel is a multi-value function. We use a numerical method to calculate the velocity correlation function of a force-free particle and the probability of a particle passing over the top of an inverse harmonic potential. We indicate the nonergodicity of the second type, i.e., the auto-correlation function of the velocity approaches to non-stationary at large times. Applied to the barrier passage problem, we find and analyse a resonant phenomenon that the dependence of the cutoff frequency is nonmonotonic when the initial directional velocity of the particle is less than the critical value, the latter is determined by the passing probability equal to 0.5. 展开更多
关键词 Nonergodicity Generalized Debye Noise Resonance Passing
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Simplified liver imaging reporting and data system for the diagnosis of hepatocellular carcinoma on gadoxetic acid-enhanced magnetic resonance imaging
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作者 Rong Lyu Wei-Juan Hu +3 位作者 Di Wang Jiao Wang Yu-Bing Ye Ke-Feng Jia 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2439-2448,共10页
BACKGROUND The liver imaging reporting and data system(LI-RADS)diagnostic table has 15 cells and is too complex.The diagnostic performance of LI-RADS for hepatocellular carcinoma(HCC)is not satisfactory on gadoxetic a... BACKGROUND The liver imaging reporting and data system(LI-RADS)diagnostic table has 15 cells and is too complex.The diagnostic performance of LI-RADS for hepatocellular carcinoma(HCC)is not satisfactory on gadoxetic acid-enhanced magnetic resonance imaging(EOB-MRI).AIM To evaluate the ability of the simplified LI-RADS(sLI-RADS)to diagnose HCC on EOB-MRI.METHODS A total of 331 patients with 356 hepatic observations were retrospectively analysed.The diagnostic performance of sLI-RADS A-D using a single threshold was evaluated and compared with LI-RADS v2018 to determine the optimal sLIRADS.The algorithms of sLI-RADS A-D are as follows:The single threshold for sLI-RADS A and B was 10 mm,that is,classified observations≥10mm using an algorithm of 10-19 mm observations(sLI-RADS A)and≥20 mm observations(sLI-RADS B)in the diagnosis table of LI-RADS v2018,respectively,while the classification algorithm remained unchanged for observations<10 mm;the single threshold for sLI-RADS C and D was 20 mm,that is,for<20 mm observations,the algorithms for<10 mm observations(sLI-RADS C)and 10-19 mm observations(sLI-RADS D)were used,respectively,while the algorithm remained unchanged for observations≥20 mm.With hepatobiliary phase(HBP)hypointensity as a major feature(MF),the final sLI-RADS(F-sLI-RADS)was formed according to the optimal sLI-RADS,and its diagnostic performance was evaluated.The times needed to classify the observations according to F-sLIRADS and LI-RADS v2018 were compared.RESULTS The optimal sLI-RADS was sLI-RADS D(with a single threshold of 20 mm),because its sensitivity was greater than that of LI-RADS v2018(89.8%vs 87.0%,P=0.031),and its specificity was not lower(89.4%vs 90.1%,P>0.999).With HBP hypointensity as an MF,the sensitivity of F-sLI-RADS was greater than that of LI-RADS v2018(93.0%vs 87.0%,P<0.001)and sLI-RADS D(93.0%vs 89.8%,P=0.016),without a lower specificity(86.5%vs 90.1%,P=0.062;86.5%vs 89.4%,P=0.125).Compared with that of LI-RADS v2018,the time to classify lesions according to FsLI-RADS was shorter(51±21 s vs 73±24 s,P<0.001).CONCLUSION The use of sLI-RADS with HBP hypointensity as an MF may improve the sensitivity of HCC diagnosis and reduce lesion classification time. 展开更多
关键词 Hepatocellular carcinoma Magnetic resonance imaging LIVER DIAGNOSIS Contrast agent
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Interface state-based bound states in continuum and below-continuum-resonance modes with high-Q factors in the rotational periodic system
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作者 杨嘉玲 史奥芊 +2 位作者 彭宇宸 彭鹏 刘建军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期288-293,共6页
We have introduced a new approach to calculate the orbital angular momentum(OAM)of bound states in continuum(BICs)and below-continuum-resonance(BCR)modes in the rotational periodic system nested inside and outside by ... We have introduced a new approach to calculate the orbital angular momentum(OAM)of bound states in continuum(BICs)and below-continuum-resonance(BCR)modes in the rotational periodic system nested inside and outside by transforming the Bloch wave number from the translational periodic system.We extensively classify and study these BICs and BCR modes,which exhibit high-quality(high-Q)factors,in different regions relative to the interface of the system.These BICs and BCR modes with a high-Q factor have been studied in detail based on distinctive structural parameters and scattering theory.The outcomes of this research break the periodic limitation of interface state-based BICs,and realize more and higher symmetry interface state-based BICs and BCR modes.Moreover,we can control the region where light is captured by adjusting the frequency,and show that the Q factor of BICs is more closely related to the ordinal number of rings and the rotational symmetry number of the system. 展开更多
关键词 bound states in the continuum below continuum resonance modes high-quality factors
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From strength to precision: A systematic review exploring the clinical utility of 7-Tesla magnetic resonance imaging in abdominal imaging
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作者 Arosh S Perera Molligoda Arachchige Ana Claudia Teixeira de Castro Gonçalves Ortega +2 位作者 Federica Catapano Letterio S Politi Michael N Hoff 《World Journal of Radiology》 2024年第1期20-31,共12页
BACKGROUND After approval for clinical use in 2017 early investigations of ultra-high-field abdominal magnetic resonance imaging(MRI)have demonstrated the feasibility as well as diagnostic capabilities of liver,kidney... BACKGROUND After approval for clinical use in 2017 early investigations of ultra-high-field abdominal magnetic resonance imaging(MRI)have demonstrated the feasibility as well as diagnostic capabilities of liver,kidney,and prostate MRI at 7-Tesla.However,the elevation of the field strength to 7-Tesla not only brought advantages to abdominal MRI but also presented considerable challenges and drawbacks,primarily stemming from heightened artifacts and limitations in Specific Absorption Rate,etc.Furthermore,evidence in the literature is relatively scarce concerning human studies in comparison to phantom/animal studies which necessitates an investigation into the evidence so far in humans and summarizing all relevant evidence.AIM To offer a comprehensive overview of current literature on clinical abdominal 7T MRI that emphasizes current trends,details relevant challenges,and provides a concise set of potential solutions.METHODS This systematic review adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.A PubMed search,utilizing Medical Subject Headings terms such as"7-Tesla"and organ-specific terms,was conducted for articles published between January 1,1985,and July 25,2023.Eligibility criteria included studies exploring 7T MRI for imaging human abdominal organs,encompassing various study types(in-vivo/ex-vivo,method development,reviews/meta-analyses).Exclusion criteria involved animal studies and those lacking extractable data.Study selection involved initial identification via title/abstract,followed by a full-text review by two researchers,with discrepancies resolved through discussion.Data extraction covered publication details,study design,population,sample size,7T MRI protocol,image characteristics,endpoints,and conclusions.RESULTS The systematic review included a total of 21 studies.The distribution of clinical 7T abdominal imaging studies revealed a predominant focus on the prostate(n=8),followed by the kidney(n=6)and the hepatobiliary system(n=5).Studies on these organs,and in the pancreas,demonstrated clear advantages at 7T.However,small bowel studies showed no significant improvements compared to traditional MRI at 1.5T.The majority of studies evaluated originated from Germany(n=10),followed by the Netherlands(n=5),the United States(n=5),Austria(n=2),the United Kingdom(n=1),and Italy(n=1).CONCLUSION Further increase of abdominal clinical MRI field strength to 7T demonstrated high imaging potential,yet also limitations mainly due to the inhomogeneous radiofrequency(RF)excitation field relative to lower field strengths.Hence,further optimization of dedicated RF coil elements and pulse sequences are expected to better optimize clinical imaging at high magnetic field strength. 展开更多
关键词 7-Tesla magnetic resonance imaging ABDOMINAL Prostate Kidney Renal PANCREAS HEPATOBILIARY Liver Small bowel
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Multisystemic recurrent Langerhans cell histiocytosis misdiagnosed with chronic inflammation at the first diagnosis:A case report
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作者 Zhan-Rong Zhang Feng Chen Hui-Juan Chen 《World Journal of Radiology》 2024年第6期232-240,共9页
BACKGROUND Langerhans cell histiocytosis(LCH)is characterized by diabetes insipidus and is an uncommon occurrence.Pathological biopsies still have a certain degree of diagnostic probability.We present a case in which ... BACKGROUND Langerhans cell histiocytosis(LCH)is characterized by diabetes insipidus and is an uncommon occurrence.Pathological biopsies still have a certain degree of diagnostic probability.We present a case in which LCH initially affected the pituitary gland.This resulted in a misdiagnosis of chronic inflammation upon pathological examination.CASE SUMMARY A 25-year-old female exhibited symptoms of diabetes insipidus.Magnetic resonance imaging revealed an enhanced foci in the pituitary gland.After surgical resection of the pituitary lesion,the pathological diagnosis was chronic inflam-mation.However,the patient later experienced bone destruction in the skull and lower limb bones.After the lower limb bone lesion was compared with the initial pituitary lesion,the final diagnosis was modified to LCH.The patient was treated with multiple chemotherapy courses.However,the patient’s condition gradually worsened,and she eventually passed away at home.CONCLUSION LCH should be considered when patients exhibit diabetes insipidus and absence of high signal intensity in the pituitary gland on sagittal T1-weighted image and abnormal enhancement in the pituitary region. 展开更多
关键词 Langerhans cell histiocytosis Pituitary gland Diabetes insipidus MULTI-system MISDIAGNOSIS Magnetic resonance imaging Case report
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Intracranial magnetic resonance venography in healthy individuals:normal anatomy and variations of the cerebral venous system
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作者 Lu Liu Jinsong Guo +10 位作者 Huimin Jiang Huimin Wei Yifan Zhou Kaiyuan Zhang Ming Li Yan Wu Jiangang Duan Ran Meng Miaowen Jiang Chen Zhou Xunming Ji 《Journal of Translational Neuroscience》 2024年第1期15-25,共11页
Objective:To evaluate the basic appearance and variation of the venous sinuses and veins in healthy individuals.Methods:Prospectively-recruited healthy volunteers completed a questionnaire and underwent magnetic reson... Objective:To evaluate the basic appearance and variation of the venous sinuses and veins in healthy individuals.Methods:Prospectively-recruited healthy volunteers completed a questionnaire and underwent magnetic resonance imaging plus contrast-enhanced magnetic resonance venography(CE-MRV)to measure their sinus diameters.Anatomical variations of cerebral venous sinuses were evaluated.Results:Fifty-eight individuals were included.The mean diameter of the left transverse sinus(LTS)(5.37±1.35 mm)was significantly smaller than that of the right transverse sinus(RTS)(6.65±1.57 mm)(P<0.001),and the average discrepancy was 19.2%.RTS dominance was noted in 55.1%of cases.Four superior sagittal sinus(SSS)anatomical variations were found.Type A was the most common and was present in 43 participants(74.1%).The SSS preferentially drained into the RTS in 32 patients(55.2%),and arachnoid granulation was observed in the transverse sinus(TS)and SSS in patients.According to our reclassification combined with Osborn’s previous research,we found that the SSS commonly drained into the RTS and that the straight sinus(StS)branched into both TSs.Conclusions:A 19%difference between the LTS and RTS provides a threshold for TS lateral dominance instead of a TS abnormality.Clinicians and radiologists should not ignore the influence of acquired pathology when the SSS drains in a non-RTS-dominant manner.Anatomical variations of the torcular herophili are frequent;the most commonly observed was the StS branching into both TSs,with the SSS draining into the RTS. 展开更多
关键词 transverse sinus healthy individuals ANATOMY magnetic resonance venography cerebral venous system
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Diagnostic Dilemma of Intracardiac Mass: Tumor versus Thrombus-Case Series and Systematic Review
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作者 Indira Acharya Ashik Pokharel +1 位作者 Raktim Ghosh Christopher J. Haas 《Journal of Biosciences and Medicines》 2024年第7期141-150,共10页
Background: The differential diagnosis for intracavitary cardiac masses is limited, typically including vegetations, tumors, or thrombi. Cardiac thrombi can often mimic cardiac tumors on imaging, creating a diagnostic... Background: The differential diagnosis for intracavitary cardiac masses is limited, typically including vegetations, tumors, or thrombi. Cardiac thrombi can often mimic cardiac tumors on imaging, creating a diagnostic challenge. Primary cardiac tumors are rare and usually benign, whereas most cardiac tumors result from metastases, commonly originating from malignancies in the breast, lung, or melanoma. Aim: This report highlights the importance of distinguishing various cardiac masses based on clinical presentations, clinical courses, and radiological features. Case Presentation: We describe two cases of cardiac masses with unique and diverse clinical features. Each case posed significant diagnostic challenges due to their distinct presentations and clinical progressions. Conclusion: These cases underscore the importance of considering both benign and metastatic origins in the differential diagnosis of intracavitary cardiac masses. Accurate differentiation between thrombi and tumors is crucial for appropriate management and treatment. 展开更多
关键词 ECHOCARDIOGRAPHY Cardiac Masses ARRHYTHMIAS Cardiac Magnetic Resonance Imaging Cardiac Thrombi
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