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Real time detection of antibody-antigen interaction using a laser scanning confocal imaging-surface plasmon resonance system 被引量:4
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作者 Zhang Hong-Yan Yang Li-Quan +5 位作者 Meng Lan Nie Jia-Cai Ning Ting-Yin Liu Wei-Min Sun Jia-Yu Wang Peng-Fei 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期224-228,共5页
A laser scanning confocal imaging-surface plasmon resonance (LSCI-SPR) instrument integrated with a wavelength-dependent surface plasmon resonance (SPR) sensor and a laser scanning confocal microscopy (LSCM) is ... A laser scanning confocal imaging-surface plasmon resonance (LSCI-SPR) instrument integrated with a wavelength-dependent surface plasmon resonance (SPR) sensor and a laser scanning confocal microscopy (LSCM) is built to detect the bonding process of human IgG and fluorescent-labeled affinity purified antibodies in real time. The shifts of resonant wavelength at different reaction time stages are obtained by SPR, corresponding well with the changes of the fluorescence intensity collected by using LSCM. The instrument shows the merits of the combination and complementation of the SPR and LSCM, with such advantages as quantificational analysis, high spatial resolution and real time monitor, which are of great importance for practical applications in biosensor and life science. 展开更多
关键词 laser scanning confocal imaging-surface plasmon resonance COMBINATION COMPLEMENTATION real time
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Novel Woods-Saxon stochastic resonance system for weak signal detection
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作者 Yong-Hui Zhou Xue-Mei Xu +3 位作者 Lin-Zi Yin Yi-Peng Ding Jia-Feng Ding Ke-Hui Sun 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期190-198,共9页
We propose a joint exponential function and Woods–Saxon stochastic resonance(EWSSR)model.Because change of a single parameter in the classical stochastic resonance model may cause a great change in the shape of the p... We propose a joint exponential function and Woods–Saxon stochastic resonance(EWSSR)model.Because change of a single parameter in the classical stochastic resonance model may cause a great change in the shape of the potential function,it is difficult to obtain the optimal output signal-to-noise ratio by adjusting one parameter.In the novel system,the influence of different parameters on the shape of the potential function has its own emphasis,making it easier for us to adjust the shape of the potential function.The system can obtain different widths of the potential well or barrier height by adjusting one of these parameters,so that the system can match different types of input signals adaptively.By adjusting the system parameters,the potential function model can be transformed between the bistable model and the monostable model.The potential function of EWSSR has richer shapes and geometric characteristics.The effects of parameters,such as the height of the barrier and the width of the potential well,on SNR are studied,and a set of relatively optimal parameters are determined.Moreover,the EWSSR model is compared with other classical stochastic resonance models.Numerical experiments show that the proposed EWSSR model has higher SNR and better noise immunity than other classical stochastic resonance models.Simultaneously,the EWSSR model is applied to the detection of actual bearing fault signals,and the detection effect is also superior to other models. 展开更多
关键词 STOCHASTIC resonance WEAK signal detection a joint EXPONENTIAL function and Woods-Saxon STOCHASTIC resonance SIGNAL-TO-NOISE ratio
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An analytical study on the second-order resonance system of tide in an ideal partially-enclosed bay
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作者 WONG Lai Ah DONG Lixian +1 位作者 CHEN Jay Chung SU Jilan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第5期1-13,共13页
In the numerical studies of a real tide M4 resonance system, the Xiangshan Port which is a partially-closed bay, Dong et al. [1999. Acta Oceanologica Sinica, 21 (3): 1-6] found the interesting phenomenon that the a... In the numerical studies of a real tide M4 resonance system, the Xiangshan Port which is a partially-closed bay, Dong et al. [1999. Acta Oceanologica Sinica, 21 (3): 1-6] found the interesting phenomenon that the advection plays an important role in inhibiting the growth of the amplitude of the tidal second-order resonance response (M4). This result is contrary to the general traditional ideas for a non-resonance system. How this phenomenon is interpreted and what internal mechanism is behind the phenomenon are the main focuses of this study. The followings are examined: (1) the dynamic features of a second-order resonance system of tide; (2) the dominating factors on the second-order resonance responses; (3) the effects of both the friction and the advection on the second-order resonance responses; and (4) their roles in dominating the second-order resonance response and internal mechanisms by using the analytical methods. The respective results show that: (1) Both the bottom friction and the advection play significant roles in dominating the magnitude of the amplitude of the second-order resonance responses; (2) the effect of the friction on the second-order resonance response depends on the distribution ratio of the work-done of the system to friction force exhausted into between the damping of the first-order system and the inner excitation of the second-order system; (3) the advection plays a positive role in increasing the amplitude of the second-order non-resonance response in the second order non-resonance of tide; (4) in a second-order resonance system of tide, the effect of the advection may be either to increase or to decrease the amplitudes of the second-order resonance responses of tide, which depends on the distribution ratio mentioned above. 展开更多
关键词 TIDE second-order resonance advection
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Quantum simulations with nuclear magnetic resonance system
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作者 Chudan Qiu Xinfang Nie Dawei L 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第4期33-42,共10页
Thanks to the quantum simulation,more and more problems in quantum mechanics which were previously inaccessible are now open to us.Capitalizing on the state-of-the-art techniques on quantum coherent control developed ... Thanks to the quantum simulation,more and more problems in quantum mechanics which were previously inaccessible are now open to us.Capitalizing on the state-of-the-art techniques on quantum coherent control developed in past few decades,e.g.,the high-precision quantum gate manipulating,the time-reversal harnessing,the high-fidelity state preparation and tomography,the nuclear magnetic resonance(NMR) system offers a unique platform for quantum simulation of many-body physics and high-energy physics.Here,we review the recent experimental progress and discuss the prospects for quantum simulation realized on NMR systems. 展开更多
关键词 nuclear magnetic resonance quantum simulation quantum phase transition quantum gravity
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Optical pumping nuclear magnetic resonance system rotating in a plane parallel to the quantization axis
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作者 丁志超 袁杰 +1 位作者 罗晖 龙兴武 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期570-570,共1页
Requested by the authors, the article entitled "Optical pumping nuclear magnetic resonance system rotating in a plane parallel to the quantization axis", published in Chinese Physics B, 2017, Vol. 26, Issue 9, Artic... Requested by the authors, the article entitled "Optical pumping nuclear magnetic resonance system rotating in a plane parallel to the quantization axis", published in Chinese Physics B, 2017, Vol. 26, Issue 9, Article No. 093301, has been withdrawn from the publication. The authors found that the axes in the rotating frame xy'z are not all time-invariant, so Eq. (12) obtained from Eq. (11) is incorrect, and the conclusion is inaccurate. 展开更多
关键词 optical pumping nuclear magnetic resonance spin polarization
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Signal modulating noise effect in bistable stochastic resonance systems and its analog simulation
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作者 肖方红 闫桂荣 谢世成 《Journal of Central South University of Technology》 EI 2006年第5期595-597,共3页
The effect of signal modulating noise in bistable stochastic resonance systems was studied theoretically and experimentally. A mathematical analysis was made on the bistable stochastic resonance model with small syste... The effect of signal modulating noise in bistable stochastic resonance systems was studied theoretically and experimentally. A mathematical analysis was made on the bistable stochastic resonance model with small system parameters. An analogue circuit was designed to perform the effect. The effect of signal modulating noise was shown in the analog simulation experiment. The analog experiment was conducted for two sinusoidal signals with different frequencies. The results show that there are a sinusoidal component corresponding to the input sinusoidal signal and a noise component presented as a Wiener process corresponding to the input white noise in the system output. By properly selecting system parameters, the effect of signal modulating noise can be manifested in the system output. 展开更多
关键词 signal modulating noise effect bistable system stochastic resonance analog simulation
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Optical pumping nuclear magnetic resonance system rotating in a plane parallel to the quantization axis
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作者 丁志超 袁杰 +1 位作者 罗晖 龙兴武 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第9期164-168,共5页
A model of an optical pumping nuclear magnetic resonance system rotating in a plane parallel to the quantization axis is presented. Different coordinate frames for nuclear spin polarization vector are introduced, and ... A model of an optical pumping nuclear magnetic resonance system rotating in a plane parallel to the quantization axis is presented. Different coordinate frames for nuclear spin polarization vector are introduced, and theoretical calculation is conducted to analyze this model. We demonstrate that when the optical pumping nuclear magnetic resonance system rotates in a plane parallel to the quantization axis, it will maintain a steady state with respect to the quantization axis which is independent of rotational speed and direction. 展开更多
关键词 optical pumping nuclear magnetic resonance spin polarization
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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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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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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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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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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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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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Structural and functional alterations in the brains of patients with anisometropic and strabismic amblyopia:a systematic review of magnetic resonance imaging studies 被引量:2
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作者 Yuxia Wang Ye Wu +1 位作者 Lekai Luo Fei Li 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第11期2348-2356,共9页
Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention.Previous clinical and neuroimaging studies have suggested that the neural mechanism... Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention.Previous clinical and neuroimaging studies have suggested that the neural mechanisms underlying strabismic amblyopia and anisometropic amblyopia may be different.Therefore,we performed a systematic review of magnetic resonance imaging studies investigating brain alterations in patients with these two subtypes of amblyopia;this study is registered with PROSPERO(registration ID:CRD42022349191).We searched three online databases(PubMed,EMBASE,and Web of Science) from inception to April 1,2022;39 studies with 633 patients(324patients with anisometropic amblyo pia and 309 patients with strabismic amblyopia) and 580 healthy controls met the inclusion criteria(e.g.,case-control designed,pee r-reviewed articles) and were included in this review.These studies highlighted that both strabismic amblyopia and anisometropic amblyopia patients showed reduced activation and distorted topological cortical activated maps in the striate and extrastriate co rtices during tas k-based functional magnetic resonance imaging with spatial-frequency stimulus and retinotopic representations,respectively;these may have arisen from abnormal visual experiences.Compensations for amblyopia that are reflected in enhanced spontaneous brain function have been reported in the early visual cortices in the resting state,as well as reduced functional connectivity in the dorsal pathway and structural connections in the ventral pathway in both anisometro pic amblyopia and strabismic amblyopia patients.The shared dysfunction of anisometro pic amblyopia and strabismic amblyopia patients,relative to controls,is also chara cterized by reduced spontaneous brain activity in the oculomotor co rtex,mainly involving the frontal and parietal eye fields and the cerebellu m;this may underlie the neural mechanisms of fixation instability and anomalous saccades in amblyopia.With regards to specific alterations of the two forms of amblyo pia,anisometropic amblyo pia patients suffer more microstructural impairments in the precortical pathway than strabismic amblyopia patients,as reflected by diffusion tensor imaging,and more significant dysfunction and structural loss in the ventral pathway.Strabismic amblyopia patients experience more attenuation of activation in the extrastriate co rtex than in the striate cortex when compared to anisometropic amblyopia patients.Finally,brain structural magnetic resonance imaging alterations tend to be lateralized in the adult anisometropic amblyopia patients,and the patterns of brain alterations are more limited in amblyopic adults than in childre n.In conclusion,magnetic resonance imaging studies provide important insights into the brain alterations underlying the pathophysiology of amblyopia and demonstrate common and specific alte rations in anisometropic amblyo pia and strabismic amblyopia patients;these alterations may improve our understanding of the neural mechanisms underlying amblyopia. 展开更多
关键词 AMBLYOPIA ANISOMETROPIA brain function magnetic resonance imaging oculomotor system precortical pathway STRABISMUS structure visual cortex
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Loss Factors and their Effect on Resonance Peaks in Mechanical Systems 被引量:1
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作者 Roman Vinokur 《Sound & Vibration》 EI 2023年第1期1-13,共13页
The loss factors and their effects on the magnitude and frequency of resonance peaks in various mechanical sys-tems are reviewed for acoustic,vibration,and vibration fatigue applications.The main trends and relationsh... The loss factors and their effects on the magnitude and frequency of resonance peaks in various mechanical sys-tems are reviewed for acoustic,vibration,and vibration fatigue applications.The main trends and relationships were obtained for linear mechanical models with hysteresis damping.The well-known features(complex module of elasticity,total loss factor,etc.)are clarified for practical engineers and students,and new results are presented(in particular,for 2-DOF in-series models with hysteresis friction).The results are of both educational and prac-tical interest and may be applied for NVH analysis and testing,mechanical and aeromechanical design,and noise and vibration control in buildings. 展开更多
关键词 Mechanical loss factor resonance peak ACOUSTICS VIBRATION structural failure noise NVH engineering systems
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Preoperative prediction of perineural invasion of rectal cancer based on a magnetic resonance imaging radiomics model:A dual-center study 被引量:2
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作者 Yan Liu Bai-Jin-Tao Sun +3 位作者 Chuan Zhang Bing Li Xiao-Xuan Yu Yong Du 《World Journal of Gastroenterology》 SCIE CAS 2024年第16期2233-2248,共16页
BACKGROUND Perineural invasion(PNI)has been used as an important pathological indicator and independent prognostic factor for patients with rectal cancer(RC).Preoperative prediction of PNI status is helpful for indivi... BACKGROUND Perineural invasion(PNI)has been used as an important pathological indicator and independent prognostic factor for patients with rectal cancer(RC).Preoperative prediction of PNI status is helpful for individualized treatment of RC.Recently,several radiomics studies have been used to predict the PNI status in RC,demonstrating a good predictive effect,but the results lacked generalizability.The preoperative prediction of PNI status is still challenging and needs further study.AIM To establish and validate an optimal radiomics model for predicting PNI status preoperatively in RC patients.METHODS This retrospective study enrolled 244 postoperative patients with pathologically confirmed RC from two independent centers.The patients underwent preoperative high-resolution magnetic resonance imaging(MRI)between May 2019 and August 2022.Quantitative radiomics features were extracted and selected from oblique axial T2-weighted imaging(T2WI)and contrast-enhanced T1WI(T1CE)sequences.The radiomics signatures were constructed using logistic regression analysis and the predictive potential of various sequences was compared(T2WI,T1CE and T2WI+T1CE fusion sequences).A clinical-radiomics(CR)model was established by combining the radiomics features and clinical risk factors.The internal and external validation groups were used to validate the proposed models.The area under the receiver operating characteristic curve(AUC),DeLong test,net reclassification improvement(NRI),integrated discrimination improvement(IDI),calibration curve,and decision curve analysis(DCA)were used to evaluate the model performance.RESULTS Among the radiomics models,the T2WI+T1CE fusion sequences model showed the best predictive performance,in the training and internal validation groups,the AUCs of the fusion sequence model were 0.839[95%confidence interval(CI):0.757-0.921]and 0.787(95%CI:0.650-0.923),which were higher than those of the T2WI and T1CE sequence models.The CR model constructed by combining clinical risk factors had the best predictive performance.In the training and internal and external validation groups,the AUCs of the CR model were 0.889(95%CI:0.824-0.954),0.889(95%CI:0.803-0.976)and 0.894(95%CI:0.814-0.974).Delong test,NRI,and IDI showed that the CR model had significant differences from other models(P<0.05).Calibration curves demonstrated good agreement,and DCA revealed significant benefits of the CR model.CONCLUSION The CR model based on preoperative MRI radiomics features and clinical risk factors can preoperatively predict the PNI status of RC noninvasively,which facilitates individualized treatment of RC patients. 展开更多
关键词 Rectal cancer Perineural invasion Magnetic resonance imaging Radiomics NOMOGRAM
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High-grade pancreatic intraepithelial neoplasia diagnosed based on changes in magnetic resonance cholangiopancreatography findings:A case report 被引量:2
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作者 Nao Furuya Atsushi Yamaguchi +13 位作者 Naohiro Kato Syuhei Sugata Takuro Hamada Takeshi Mizumoto Yuzuru Tamaru Ryusaku Kusunoki Toshio Kuwai Hirotaka Kouno Kazuya Kuraoka Yoshiyuki Shibata Sho Tazuma Takeshi Sudo Hiroshi Kohno Shiro Oka 《World Journal of Clinical Cases》 SCIE 2024年第8期1487-1496,共10页
BACKGROUND High-grade pancreatic intraepithelial neoplasia(PanIN)exhibits no mass and is not detected by any examination modalities.However,it can be diagnosed by pancreatic juice cytology from indirect findings.Most ... BACKGROUND High-grade pancreatic intraepithelial neoplasia(PanIN)exhibits no mass and is not detected by any examination modalities.However,it can be diagnosed by pancreatic juice cytology from indirect findings.Most previous cases were diagnosed based on findings of a focal stricture of the main pancreatic duct(MPD)and caudal MPD dilatation and subsequent pancreatic juice cytology using endoscopic retrograde cholangiopancreatography(ERCP).We experienced a case of high-grade PanIN with an unclear MPD over a 20-mm range,but without caudal MPD dilatation on magnetic resonance cholangiopancreatography(MRCP).CASE SUMMARY A 60-year-old female patient underwent computed tomography for a follow-up of uterine cancer post-excision,which revealed pancreatic cysts.MRCP revealed an unclear MPD of the pancreatic body at a 20-mm length without caudal MPD dilatation.Thus,course observation was performed.After 24 mo,MRCP revealed an increased caudal MPD caliber and a larger pancreatic cyst.We performed ERCP and detected atypical cells suspected of adenocarcinoma by serial pancreatic juice aspiration cytology examination.We performed a distal pancreatectomy and obtained a histopathological diagnosis of high-grade PanIN.Pancreatic parenchyma invasion was not observed,and curative resection was achieved.CONCLUSION High-grade Pan-IN may cause MPD narrowing in a long range without caudal MPD dilatation. 展开更多
关键词 Pancreatic cancer Pancreatic intraepithelial neoplasm High-grade pancreatic intraepithelial neoplasm Magnetic resonance cholangiopancreatography Carcinoma in situ Case report
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Staging liver fibrosis with various diffusion-weighted magnetic resonance imaging models 被引量:1
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作者 Yan-Li Jiang Juan Li +6 位作者 Peng-Fei Zhang Feng-Xian Fan Jie Zou Pin Yang Peng-Fei Wang Shao-Yu Wang Jing Zhang 《World Journal of Gastroenterology》 SCIE CAS 2024年第9期1164-1176,共13页
BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver fibrosis.However,its diagnostic performance is inconsistent among studies.Therefore,it is worth studying the diagnostic value of various diff... BACKGROUND Diffusion-weighted imaging(DWI)has been developed to stage liver fibrosis.However,its diagnostic performance is inconsistent among studies.Therefore,it is worth studying the diagnostic value of various diffusion models for liver fibrosis in one cohort.AIM To evaluate the clinical potential of six diffusion-weighted models in liver fibrosis staging and compare their diagnostic performances.METHODS This prospective study enrolled 59 patients suspected of liver disease and scheduled for liver biopsy and 17 healthy participants.All participants underwent multi-b value DWI.The main DWI-derived parameters included Mono-apparent diffusion coefficient(ADC)from mono-exponential DWI,intravoxel incoherent motion model-derived true diffusion coefficient(IVIM-D),diffusion kurtosis imaging-derived apparent diffusivity(DKI-MD),stretched exponential model-derived distributed diffusion coefficient(SEM-DDC),fractional order calculus(FROC)model-derived diffusion coefficient(FROC-D)and FROC model-derived microstructural quantity(FROC-μ),and continuous-time random-walk(CTRW)model-derived anomalous diffusion coefficient(CTRW-D)and CTRW model-derived temporal diffusion heterogeneity index(CTRW-α).The correlations between DWI-derived parameters and fibrosis stages and the parameters’diagnostic efficacy in detecting significant fibrosis(SF)were assessed and compared.RESULTS CTRW-D(r=-0.356),CTRW-α(r=-0.297),DKI-MD(r=-0.297),FROC-D(r=-0.350),FROC-μ(r=-0.321),IVIM-D(r=-0.251),Mono-ADC(r=-0.362),and SEM-DDC(r=-0.263)were significantly correlated with fibrosis stages.The areas under the ROC curves(AUCs)of the combined index of the six models for distinguishing SF(0.697-0.747)were higher than each of the parameters alone(0.524-0.719).The DWI models’ability to detect SF was similar.The combined index of CTRW model parameters had the highest AUC(0.747).CONCLUSION The DWI models were similarly valuable in distinguishing SF in patients with liver disease.The combined index of CTRW parameters had the highest AUC. 展开更多
关键词 Liver fibrosis Magnetic resonance imaging Diffusion-weighted magnetic resonance Liver biopsy Significant fibrosis
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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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Realizing reliable XOR logic operation via logical chaotic resonance in a triple-well potential system
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作者 杨华美 姚元根 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期123-127,共5页
There exists an optimal range of intensity of a chaotic force in which the behavior of a chaos-driven bistable system with two weak inputs can be consistently mapped to a specific logic output. This phenomenon is call... There exists an optimal range of intensity of a chaotic force in which the behavior of a chaos-driven bistable system with two weak inputs can be consistently mapped to a specific logic output. This phenomenon is called logical chaotic resonance(LCR). However, realization of a reliable exclusive disjunction(XOR) through LCR has not been reported.Here, we explore the possibility of using chaos to enhance the reliability of XOR logic operation in a triple-well potential system via LCR. The success probability P of obtaining XOR logic operation can take the maximum value of 1 in an optimal window of intensity D of a chaotic force. Namely, success probability P displays characteristic bell-shaped behavior by altering the intensity of the chaotic driving force, indicating the occurrence of LCR. Further, the effects of periodic force on LCR have been investigated. For a subthreshold chaotic force, a periodic force with appropriate amplitude and frequency can help enhance the reliability of XOR logic operation. Thus, LCR can be effectively regulated by changing the amplitude and frequency of the periodic force. 展开更多
关键词 stochastic resonance logical stochastic resonance logical chaotic resonance XOR logic triple-well potential system
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