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Piezoelectric Power Harvesting via Acoustic-Pressure Driven by Low-Speed Wind-Force with Resonating-Tube and Wind-Collector
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作者 Seiichi Deguchi Hiroya Taguchi +7 位作者 Hajime Arimura Noriyuki Kobayashi Norifumi Isu Kentaro Takagi Tsuyoshi Inoue Takashi Nozoe Seigo Saito Takahiko Sano 《Journal of Power and Energy Engineering》 2018年第11期53-64,共12页
Wind-driven power harvestings attract attentions since their target wind speeds are quite low less than the so-called cut-in wind speed, which is generally recognized as around 3 m/s. The extant power harvestings driv... Wind-driven power harvestings attract attentions since their target wind speeds are quite low less than the so-called cut-in wind speed, which is generally recognized as around 3 m/s. The extant power harvestings driven by wind-induced-air-column-resonations (i.e. acoustic-pressures) are still lacking simplicity, scale flexibility and solid strategies for practical applications. Therefore, the piezoelectric power harvesters via acoustic-pressures driven by low-speedwind-forces with resonating-tubes and wind-collectors were invented so as to complement all the lacks. The wind-collector as well as the resonating-tube contributed to upraise the power harvesting density. The champion power harvesting density of 19.5 nW/dm2 could be procured at 2.3 m/s of an artificial wind and the optimal resonating-tube and wind-collector. Power harvesting proofs from the natural wind with low mean speeds down to about 0.6 m/s were successfully obtained. The cut-in wind speed of the prototype piezoelectric power harvester was found to be quite low as about 0.4 m/s, signifying its ubiquity. Finally, a multi-bundle pendant-type piezoelectric power harvester was specifically presented together with professing the solid and multiple strategies for practical applications. 展开更多
关键词 PIEZOELECTRIC POWER Generation Low WIND Speed resonating TUBE WIND COLLECTOR POWER HARVESTING Practical Demonstration
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Bound and Resonating Multiquark Configurations
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作者 Jean-Marc Richard 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期8-12,共5页
We review the predictions of quark models for multiquark configurations that are bound or resonant states,and compare different methods for estimating the properties of resonances.
关键词 QUARK CONFIGURATION RESONANT
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A radiomics approach for predicting gait freezing in Parkinson's disease based on resting-state functional magnetic resonance imaging indices:A cross-sectional study 被引量:1
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作者 Miaoran Guo Hu Liu +6 位作者 Long Gao Hongmei Yu Yan Ren Yingmei Li Huaguang Yang Chenghao Cao Guoguang Fan 《Neural Regeneration Research》 2026年第4期1621-1627,共7页
Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indice... Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indices,has provided a fresh perspective and valuable insight into the study of freezing of gait in Parkinson's disease.It has been revealed that Parkinson's disease is accompanied by widespread irregularities in inherent brain network activity.However,the effective integration of the multi-level indices of resting-state functional magnetic resonance imaging into clinical settings for the diagnosis of freezing of gait in Parkinson's disease remains a challenge.Although previous studies have demonstrated that radiomics can extract optimal features as biomarkers to identify or predict diseases,a knowledge gap still exists in the field of freezing of gait in Parkinson's disease.This cross-sectional study aimed to evaluate the ability of radiomics features based on multi-level indices of resting-state functional magnetic resonance imaging,along with clinical features,to distinguish between Parkinson's disease patients with and without freezing of gait.We recruited 28 patients with Parkinson's disease who had freezing of gait(15 men and 13 women,average age 63 years)and 30 patients with Parkinson's disease who had no freezing of gait(16 men and 14 women,average age 64 years).Magnetic resonance imaging scans were obtained using a 3.0T scanner to extract the mean amplitude of low-frequency fluctuations,mean regional homogeneity,and degree centrality.Neurological and clinical characteristics were also evaluated.We used the least absolute shrinkage and selection operator algorithm to extract features and established feedforward neural network models based solely on resting-state functional magnetic resonance imaging indicators.We then performed predictive analysis of three distinct groups based on resting-state functional magnetic resonance imaging indicators indicators combined with clinical features.Subsequently,we conducted 100 additional five-fold cross-validations to determine the most effective model for each classification task and evaluated the performance of the model using the area under the receiver operating characteristic curve.The results showed that when differentiating patients with Parkinson's disease who had freezing of gait from those who did not have freezing of gait,or from healthy controls,the models using only the mean regional homogeneity values achieved the highest area under the receiver operating characteristic curve values of 0.750(with an accuracy of 70.9%)and 0.759(with an accuracy of 65.3%),respectively.When classifying patients with Parkinson's disease who had freezing of gait from those who had no freezing of gait,the model using the mean amplitude of low-frequency fluctuation values combined with two clinical features achieved the highest area under the receiver operating characteristic curve of 0.847(with an accuracy of 74.3%).The most significant features for patients with Parkinson's disease who had freezing of gait were amplitude of low-frequency fluctuation alterations in the left parahippocampal gyrus and two clinical characteristics:Montreal Cognitive Assessment and Hamilton Depression Scale scores.Our findings suggest that radiomics features derived from resting-state functional magnetic resonance imaging indices and clinical information can serve as valuable indices for the identification of freezing of gait in Parkinson's disease. 展开更多
关键词 amplitude of low-frequency fluctuation degree centrality feedforward neural network freezing of gait machine learning parahippocampal gyrus Parkinson's disease receiver operating characteristic regional homogeneity resting-state functional magnetic resonance imaging
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Gold nanowire bias-core PCF-SPR temperature and refractive index sensing
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作者 HOU Shang-lin DONG Jie +4 位作者 YANG Xu-dong LIU Qing-min XIE Cai-jian WU Gang YAN Zu-yong 《中国光学(中英文)》 北大核心 2026年第2期382-394,共13页
To address the challenges of complex metallic film coating processes and low integration in single-parameter detection for existing photonic crystal fiber surface plasmon resonance(PCF-SPR)sensors,a dual-parameter sen... To address the challenges of complex metallic film coating processes and low integration in single-parameter detection for existing photonic crystal fiber surface plasmon resonance(PCF-SPR)sensors,a dual-parameter sensor based on gold nanowire-integrated bias-core PCF-SPR is proposed.Unlike conventional in-hole coatings or metallic film structures,the gold nanowires are directly attached to the fiber cladding via chemical vapor deposition(CVD),eliminating uneven coating issues and significantly simplifying fabrica-tion.By optimizing the asymmetric bias-core fiber structure and leveraging the strong localized field en-hancement of gold nanowires,the sensor achieves high-sensitivity synchronous detection of temperature(25−60℃)and refractive index(1.31−1.40)in dual-polarization modes.The simulation results demonstrate that the x-polarization mode can achieve 1.31−1.40 refractive index detection with maximum wavelength sensitivity and amplitude sensitivity of 14800 nm/RIU and−1724.25 RIU^(−1),and maximum refractive index resolution of 6.75×10^(−6)RIU.The y-polarization mode achieves refractive index detection range of 1.34−1.40,and the maximum wavelength sensitivity and amplitude sensitivity are 28400 nm/RIU and−1298.93 RIU^(−1),and the maximum refractive index resolution is 3.52×10^(−6)RIU.For temperature sensing,the sensor exhibits a wavelength sensitivity of 7.8 nm/℃and a high resolution of 1.38×10^(−6)℃over the range of 25−60℃.This design synergizes gold nanowires and the bias-core architecture to simplify fabrication while enabling multi-parameter detection.The proposed sensor offers new insights for integrated applications in biochemical mon-itoring,environmental sensing,and related fields. 展开更多
关键词 photonic crystal fiber surface plasmon resonance gold nanowires TEMPERATURE sensor
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Photocatalytic Radical-Mediated Synthesis of Unnaturalα-Amino Acids from Heteroaryl Aldehydes
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作者 Ren Ke Zhang Guanglu +3 位作者 Niu Yifan Wang Xiaomeng Chen Canyu Jiang Min 《有机化学》 北大核心 2026年第1期215-224,共10页
Non-naturalα-amino acids(α-AAs)are pivotal in drug and catalysis,yet their synthesis remains challenges.A photocatalytic strategy for the direct construction of N-heteroaryl-containingα-AAs from heteroaryl aldehyde... Non-naturalα-amino acids(α-AAs)are pivotal in drug and catalysis,yet their synthesis remains challenges.A photocatalytic strategy for the direct construction of N-heteroaryl-containingα-AAs from heteroaryl aldehydes via acyl radical intermediates is reported.This method exhibits exceptional functional group tolerance and enables late-stage diversification of peptides and carbonyl-group derivatization.Mechanistic studies confirm a radical-based pathway,while applications in peptide modification highlight its utility in bioorganic chemistry. 展开更多
关键词 PHOTOCATALYTIC non-natural amino acids heteroaryl aldehydes acyl radical electron paramagnetic resonance
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美国《保健物理》(Health Physics)杂志英文摘要(2026年130卷第1期)
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《辐射防护》 北大核心 2026年第2期174-181,共8页
Evaluating Adherence to Safety Standards for Physical Space Design, Equipment, and Patient and Staff Protection in Magnetic Resonance Imaging Centers:A Descriptive Cross-sectional Study Amirreza Sadeghinasab1, Jafar F... Evaluating Adherence to Safety Standards for Physical Space Design, Equipment, and Patient and Staff Protection in Magnetic Resonance Imaging Centers:A Descriptive Cross-sectional Study Amirreza Sadeghinasab1, Jafar Fatahiasl2, Mahmoud Mohammadi-Sadr1, Masoud Heydari Kahkesh3, and Marziyeh Tahmasbi2(1.Department of Medical Physics, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran;2.Department of Radiologic Technology, School of Allied Medical Sciences, Ahvaz, Jundishapur University of Medical Sciences, Ahvaz, Iran;3.Department of Radiology and Radiotherapy, School of Allied Medical Sciences, Tehran University of Medical Sciences, Tehran, Iran)Abstract:Magnetic resonance imaging(MRI) has revolutionized disease diagnosis and treatment.However, the technology poses safety risks, such as exposure to magnetic fields, RF pulses, and cryogens, necessitating strict adherence to safety protocols to protect patients and healthcare workers. 展开更多
关键词 adherence safety standards magnetic resonance imaging physical space design patient staff protection allied medical sciences safety standards medical physics radiologic technology
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Versatile and reconfigurable integrated silicon nitride photonic microresonator
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作者 Tong Lin Haoran Wang +7 位作者 Xiaoyu Hao Liu Li Ziyang Xiong Hao Deng Yan Fan Shihua Chen Junpeng Lu Zhenhua Ni 《Advanced Photonics Nexus》 2026年第1期169-177,共9页
Unlocking the full potential of integrated photonics requires versatile,multi-functional devices that can adapt to diverse application demands.However,confronting this challenge with conventional singlefunction resona... Unlocking the full potential of integrated photonics requires versatile,multi-functional devices that can adapt to diverse application demands.However,confronting this challenge with conventional singlefunction resonators often results in cumbersome system designs.We present an elegant solution:a versatile and reconfigurable dual-polarization Si_(3)N_(4)microresonator that represents a new perspective in on-chip photonic designs.Our device can be dynamically reconfigured into three distinct topologies:a Möbius-like microcavity,a Fabry-Pérot resonator,and a microring resonator.This unprecedented functionality is enabled by a tunable balanced Mach-Zehnder interferometer that facilitates controllable mutual mode coupling of counterpropagating light using a single control knob.We experimentally demonstrate that the device not only supports polarization-diverse operation on a compact footprint but also gives rise to a wide variety of physical phenomena,including a standing wave cavity,a traveling wave cavity,free spectral range multiplication,and the photonic pinning effect.These behaviors are accurately modeled using the transfer matrix method and intuitively explained by the temporal coupled-mode theory.Our results underscore the potential for a chip-scale platform to realize reconfigurable reconstructive spectrometers and on-chip synthetic dimensions for topological physics. 展开更多
关键词 silicon nitride optical cavity reconfigurable photonics microring resonator Fabry-Pérot resonator polarization diversity
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Prognostic value of left ventricular phenotypes by cardiac magnetic resonance in elderly and non-elderly patients
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作者 Rungroj Krittayaphong Thammarak Songsangjinda +1 位作者 Kanchalaporn Jirataiporn Ahthit Yindeengam 《Journal of Geriatric Cardiology》 2026年第2期69-82,I0001,I0002,共16页
BACKGROUND Many conditions may affect left ventricular(LV)phenotypes which have been classified according to LV mass and geometry.There is limited data on the prognostic value of LV phenotypes classified by cardiac ma... BACKGROUND Many conditions may affect left ventricular(LV)phenotypes which have been classified according to LV mass and geometry.There is limited data on the prognostic value of LV phenotypes classified by cardiac magnetic resonance(CMR).This study aimed to determine the prognostic value of LV phenotypes in elderly and non-elderly patients with known or suspected coronary artery disease.METHODS This is a retrospective cohort study among patients who underwent stress or viability CMR.LV phenotypes were classified according to the LV mass index,the LV end-diastolic volume index and the LV mass/volume ratio,into normal,concentric remodeling,concentric hypertrophy,and eccentric hypertrophy.The primary outcome was a composite of death or heart failure.RESULTS A total of 3289 patients was studied.The average age was 68.0±12.7 years,52.2%of patients were women.Elderly were defined as age≥65 years accounting for 63.9%of the cohort.LV phenotypes were normal,concentric remodeling,concentric hypertrophy,and eccentric hypertrophy at 74.5%,5.8%,9.2%,and 10.5%,respectively.The median duration of follow-up was 41.4 months.The composite outcome of death or heart failure occurred in 7.3%of patients.The prognostic impact of LV phenotypes was more pronounced in the elderly,with eccentric hypertrophy showing the worst prognosis,followed by concentric hypertrophy and concentric remodeling with the adjusted hazard ratio(95%CI)of 2.37(1.72–3.25),1.53(1.12–2.08),and 1.14(0.76–1.71),respectively,compared to normal phenotype.Patients with eccentric hypertrophy also demonstrated abnormal global longitudinal LV strain,left atrial strain,and extracellular volume fraction.CONCLUSIONS LV phenotypes by CMR independently predict adverse clinical outcomes in elderly patients with known or suspected coronary artery disease.In non-elderly patients,the prognostic value of LV phenotypes was less evident.Assessment of LV phenotypes may be useful for risk stratification. 展开更多
关键词 retrospective cohort study ELDERLY left ventricular phenotype lv phenotypes cardiac magnetic resonance cmr non elderly cmrlv phenotypes cardiac magnetic resonance
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Energy dynamics and circuit implementation for a neuron with a memcapacitive membrane
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作者 Binchi WANG Yitong GUO +1 位作者 Guodong REN Jun MA 《ENGINEERING Information Technology & Electronic Engineering》 2026年第1期59-70,共12页
The output voltages for the capacitive elements of a neural circuit model can be mapped into dimensionless capacitive variables,which present firing patterns similar to the membrane potentials detected in biological n... The output voltages for the capacitive elements of a neural circuit model can be mapped into dimensionless capacitive variables,which present firing patterns similar to the membrane potentials detected in biological neurons.The inclusion of a memcapacitor also en‐ables consideration of membrane deformation effects,enhancing the model’s capacity to simulate neuronal behavior across varying physio‐logical and environmental conditions.In this study,a capacitor and a memcapacitor are connected through a linear resistor in parallel with other electric components in different branch circuits composed of an inductor and a nonlinear resistor.The electrical activities in a neuron with a double-layer membrane and two capacitive variables are discussed in detail after converting the nonlinear equations for the neural circuit into a theoretical neuron model.A dimensionless neuron model and its corresponding energy function are derived.The field energy function for the neural circuit is converted into an equivalent Hamilton energy function and further validated via the Helmholtz theorem.Furthermore,the average value of energy serves as an indicator for predicting stochastic resonance,as supported by analyzing the distribu‐tion of the coefficient of variation.The neuronal firing patterns are shown to be energy-dependent.An adaptive control strategy is proposed to regulate mode transitions in electrical activities of the neuron.An analog equivalent circuit is constructed to experimentally verify the nu‐merical results,thereby supporting the reliability of the proposed neuron model. 展开更多
关键词 Neural circuit Neuron model Hamilton energy Memcapacitor Coherence resonance
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Nonreciprocal transmission in a dual WGM resonators-waveguide system via synergistic Sagnac and scattering effects
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作者 Gang Li Yong Yong Gong +3 位作者 De-Xiu Qiu Ying Qiao Zhang Chengshou An Xing Ri Jin 《Communications in Theoretical Physics》 2026年第2期15-24,共10页
We propose a scheme to achieve nonreciprocal single-photon transmission in a system consisting of a spinning whispering-gallery-mode resonator and a stationary resonator containing a scatterer,both coupled to a one-di... We propose a scheme to achieve nonreciprocal single-photon transmission in a system consisting of a spinning whispering-gallery-mode resonator and a stationary resonator containing a scatterer,both coupled to a one-dimensional waveguide.By tuning the Sagnac-Fizeau shift induced by the spinning resonator,high-contrast nonreciprocal transmission in both forward and backward directions can be realized.Furthermore,we investigate the influences of system parameters including waveguide-resonator coupling strength,inter-mode coupling strengths within two resonators,and inter-cavity coupling strength on nonreciprocal transmissions.The results indicate that the synergistic regulation of these parameters can adjust the position of the nonreciprocal transmission peak and achieve high-contrast nonreciprocal transmission. 展开更多
关键词 nonreciprocal transmission WGM resonator SCATTERER Sagnac-Fizeau shift
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Insights into biodegradable Mn-incorporated Fe-based scaffolds in orthopedics:bridging manufacturing techniques,physicomechanical properties,and multifunctional bioapplications
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作者 Xin Huang Ming-Chun Zhao +7 位作者 Qi Yin Jiangang Yao Ying-Chao Zhao Dengfeng Yin Rongchang Zeng Ke Yang Cuie Wen Andrej Atrens 《International Journal of Extreme Manufacturing》 2026年第1期383-423,共41页
Biodegradable metals(BMs)have shown significant potential for applications in the field of orthopedic implants.These materials gradually degrade after implantation,eventually disappear without residue,provide necessar... Biodegradable metals(BMs)have shown significant potential for applications in the field of orthopedic implants.These materials gradually degrade after implantation,eventually disappear without residue,provide necessary mechanical support during degradation,and closely integrate with bone tissues.Fe-based BMs are particularly notable for their good mechanical properties and biocompatibility.However,their slow degradation rate is a limitation.The emergence of Mn-incorporated Fe-based alloys(Fe-Mn alloys)offers the possibilities for addressing issues of slow degradation rate and incompatibility of magnetic resonance imaging(MRI)for Fe alloys.This review summarizes the advantages of Fe-Mn alloys as orthopedic implants,and the cutting-edge advances in degradation,mechanical and magnetic properties,and osteogenic performance.The cytotoxicity issue is addressed for the porous structured Fe-Mn alloys caused by the enrichment of manganese ions,and thus the main challenge and the development are involved for the Fe-Mn alloys to achieve a balance among biocompatibility,structure,and degradation rate.Also the perspectives are proposed for Fe-Mn alloys as orthopedic implants. 展开更多
关键词 Fe-Mn alloys BIODEGRADATION orthopedic application mechanical properties BIOCOMPATIBILITY magnetic resonance imaging
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What is the pathophysiology of inflammation-induced cortical injury in the perinatal brain?
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作者 Sharmony B.Kelly Alistair J.Gunn +1 位作者 Rodney W.Hunt Robert Galinsky 《Neural Regeneration Research》 2026年第2期502-505,共4页
Perinatal exposure to infection/inflammation is highly associated with neural injury,and subsequent impaired cortical growth,disturbances in neuronal connectivity,and impaired neurodevelopment.However,our understandin... Perinatal exposure to infection/inflammation is highly associated with neural injury,and subsequent impaired cortical growth,disturbances in neuronal connectivity,and impaired neurodevelopment.However,our understanding of the pathophysiological substrate underpinning these changes in brain structure and function is limited.The objective of this review is to summarize the growing evidence from animal trials and human cohort studies that suggest exposure to infection/inflammation during the perinatal period promotes regional impairments in neuronal maturation and function,including loss of high-frequency electroencephalographic activity,and reduced growth and arborization of cortical dendrites and dendritic spines resulting in reduced cortical volume.These inflammation-induced disturbances to neuronal structure and function are likely to underpin subsequent disturbances to cortical development and connectivity in fetuses and/or newborns exposed to infection/inflammation during the perinatal period,leading,in the long term,to impaired neurodevelopment.The combined use of early electroencephalography monitoring with neuroimaging techniques that enable detailed evaluation of brain microstructure,and the use of therapeutics that successfully target systemic and central nervous system inflammation could provide an effective strategy for early detection and therapeutic intervention. 展开更多
关键词 anti-inflammatory therapies cerebral cortex CHORIOAMNIONITIS ELECTROENCEPHALOGRAPHY magnetic resonance imaging neonatal sepsis NEURODEVELOPMENT NEUROINFLAMMATION neurons
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Proprioception deficits in chronic ankle instability associated with structural and functional alternations in cerebellar vermis
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作者 Xiao'ao Xue Yuwen Zhang +7 位作者 Le Yu Qianru Li Yiran Wang Zikun Wang Shanshan Zheng Yang Sun He Wang Yinghui Hua 《Sports Medicine and Health Science》 2026年第1期96-101,共6页
Purpose:Ankle proprioception deficits have been widely reported in patients with chronic ankle instability(CAI),but their central neuropathological mechanisms have not been fully discussed.So,we aimed to figure out wh... Purpose:Ankle proprioception deficits have been widely reported in patients with chronic ankle instability(CAI),but their central neuropathological mechanisms have not been fully discussed.So,we aimed to figure out whether the structural and functional features of the cerebellar vermis differed between patients with CAI and healthy controls,and are associated with proprioception deficits in patients.Methods:Twenty-two patients and 25 control individuals were enrolled in a cross-sectional investigation.All participants underwent structural and resting-state functional magnetic resonance imaging scanning to calculate voxel-based morphometry(VBM)and fractional amplitude of low-frequency fluctuation(fALFF)of the vermis.Between-group comparisons of the ankle instability-related subregions of the vermis were performed.Correlation analyses were performed between the outcomes of the surviving subregions and the proprioceptive scores of the ankle inversion discrimination apparatus for landing test.Results:The subregion of vermis Ⅳ/Ⅴ survived the multiple comparison correction to reveal a lower VBM value in patients than in healthy controls(Cohen's d=-0.968).The patients also showed significantly higher fALFF(Cohen's d=0.666)in this subregion.After controlling the demographic features,the proprioceptive scores were significantly correlated with VBM(r=0.622)and fALFF values(r=-0.512)in the group of patients.Conclusions:Patients with CAI have lower gray matter volume and higher activity intensity in the cerebellar vermis than healthy control.The more severe proprioception deficits were significantly associated with the vermal volume and activity,which might be able to facilitate future diagnoses and treatments for CAI. 展开更多
关键词 Ankle injuries PROPRIOCEPTION Cerebellar vermis Magnetic resonance imaging
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Nonlinear resonance of rotating solar-sail membrane under solar thermal and pressure excitations
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作者 Jinduo Chen Aiming Shi +1 位作者 Earl H.Dowell Yang Pei 《Acta Mechanica Sinica》 2026年第1期325-343,共19页
This study explores the nonlinear resonance of a rotating solar sail membrane exposed to time-varying solar thermal and solar radiation pressure.The sail membrane is modeled using a cantilever membrane,applying the vo... This study explores the nonlinear resonance of a rotating solar sail membrane exposed to time-varying solar thermal and solar radiation pressure.The sail membrane is modeled using a cantilever membrane,applying the von Kármán theory for membrane large deflection.The membrane’s nonlinear equation is derived by employing the Lagrange equation while accounting for excitations from solar thermal and radiation pressure.The equation is solved via the Rayleigh-Ritz method.The bifurcation diagram of membrane motion is applied to reveal membrane resonance responses under different solar sail rotating frequencies.The displacement time history,phase portrait,Poincarémap,frequency spectrum,and the largest Lyapunov exponent are used to study nonlinear vibrations that occur near resonance regions.The results indicate that time-varying thermal loading excites membrane motions with multiple natural frequencies by the parametric resonance mechanics,leading to the onset of membrane chaotic motion.The membrane’s primary resonance is stimulated in harmonic oscillation by the time-varying radiation pressure.The divergence instability caused by thermal excitation is also illustrated by comparing the membrane’s vibration amplitude with and without thermal excitation.The membrane’s nonlinear vibration characteristics vary significantly with solar illumination angles,the membrane’s thermal expansion coefficients,and structural damping. 展开更多
关键词 Solar-sail membrane resonance Thermal excitation Parametrically excited system CHAOS
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Synergistic design of ultra-wide low-frequency continuous bandgap metastructure for audible noise attenuation
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作者 Dongxu GUO Xiaolong ZHANG +2 位作者 Ruilan TIAN Xiangyang LI Minghao WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第3期473-496,共24页
Local resonant acoustic metamaterials have broad applications in sound insulation,yet their single-configuration designs often exhibit limited and discontinuous bandgap widths,hindering full-frequency noise attenuatio... Local resonant acoustic metamaterials have broad applications in sound insulation,yet their single-configuration designs often exhibit limited and discontinuous bandgap widths,hindering full-frequency noise attenuation across the human auditory range.This study presents a double-phase fidget-spinner-shaped acoustic metamaterial(DFAM),specifically designed to achieve an ultra-broad,low-frequency continuous bandgap by means of synergistic structural optimization,enabling effective and robust control of audible noise.Based on Bloch's theorem and the finite element method,the dispersion relation of the DFAM structure is calculated and verified by the transmission loss curves.The propagation characteristics of sound waves within the structure are further analyzed for noise frequencies that fall within the passband.The influence of the geometric and physical parameters on the bandgap is investigated,and the corresponding transmission loss in the propagation direction is further calculated.A hybrid collaborative design strategy,leveraging multi-parameter optimization and bandgap complementarity,is developed to construct a metastructure with continuous bandgap coverage from 20 Hz to 1000 Hz.The resulting metastructure demonstrates exceptional broadband noise attenuation,achieving a total bandgap width of 876.3 Hz(87.63% of the target range)with the transmission loss up to-762.78 d B in a three-periodic arrangement.The simulation and experimental results for the transmission loss of the DFAM metastructure show strong agreement in the low-frequency range.This work provides a novel framework for designing ultra-wide low-frequency continuous bandgap metastructures,offering significant potential for noise mitigation in complex environments. 展开更多
关键词 acoustic metastructure local resonance continuous bandgap noise attenuation synergistic design
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Locally resonant plate model considering the rotation coupling effect
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作者 Hefan DONG Linjuan WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第2期369-388,共20页
In this paper,a theoretical model is established for locally resonant plates with general resonators,and the corresponding governing equation is derived.The model provides a mathematical demonstration of the locally r... In this paper,a theoretical model is established for locally resonant plates with general resonators,and the corresponding governing equation is derived.The model provides a mathematical demonstration of the locally resonant effect,which contains two parts:the first part is induced by translation coupling,and the second part is induced by rotation coupling.The second part cannot be reflected by most existing theoretical models.The analytical solutions of the dynamic response are compared with the direct numerical simulation(DNS)results for two locally resonant plates with different resonator types,thereby validating the general applicability of the present model.The rotation coupling effect leads to the frequency-dependent effective rotational inertia density and anisotropic dispersion relation of the locally resonant plate,as well as the enhancement of the structural vibration suppression ability. 展开更多
关键词 METAMATERIAL locally resonant plate vibration suppression rotation coupling
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Imaging Findings of Sarcomatoid Carcinoma of the Ureter:A Case Report
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作者 Wenyu Cai Xiaofen Ma 《Proceedings of Anticancer Research》 2026年第1期94-100,共7页
Background:Sarcomatoid carcinoma of the ureter(SCU)is a highly aggressive and relatively uncommon malignant tumor of the urinary tract.Its frequency is quite low,and its prognosis is very bad when compared to other ca... Background:Sarcomatoid carcinoma of the ureter(SCU)is a highly aggressive and relatively uncommon malignant tumor of the urinary tract.Its frequency is quite low,and its prognosis is very bad when compared to other cancers of the urinary system.SCU clinical reports are still hard to come by.MRI and PEI/CT imaging of ureteral sarcomatoid cancer is presented in this case to promote diagnostic awareness and comprehension of the imaging characteristics of this uncommon illness.Method:The patient had ureteral sarcomatoid cancer,which was verified by pathological investigation after ureteroscopic biopsy.The patient’s clinical information,imaging results,surgical outcomes,and pathological findings were gathered.A retrospective study was carried out in combinationwith pertinent national and international literature.Results:An 84-year-old female patient was admitted for“left flank discomfort lasting over one month.”MRI revealed an irregular soft tissue mass in the middle-lower segment of the left ureter.T2-weighted imaging showed an unevenly slightly hyperintense signal.Diffusion-weighted imaging demonstrated restricted diffusion.Contrastenhanced imaging exhibited heterogeneous enhancement.PET/CT demonstrated significantly increased fluorodeoxyglucose metabolism in the mass with secondary left upper urinary tract obstruction.Concurrent findings included a solitary metastatic lesion in hepatic segment S6 and multiple lymph node metastases along the left common iliac and external iliac arteries.Preoperative diagnosis suggested a malignant tumor of the ureter.The patient underwent left nephroureteroscopy with biopsy,and the postoperative pathological diagnosis was ureteral sarcomatoid carcinoma.Conclusion:Ureteral sarcomatoid carcinoma is a rare,highly malignant,and aggressive tumor with nonspecific imaging features,typically presenting as an invasively growing mass.Diagnosis relies on postoperative pathology and immunohistochemical examination.MRI and PET/CT scans are valuable for preoperative localization and characterization,tumor staging,treatment planning,and postoperative follow-up.The prognosis is extremely negative.The main treatment option is radical surgery,although constant monitoring is necessary since early recurrence and metastases are frequent after surgery. 展开更多
关键词 URETER Sarcomatoid carcinoma Magnetic resonance imaging Positron emission tomography Imaging diagnosis
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A Simulation-Based Study of a Black Phosphorus-Based Complex Multilayer SPR-Based Optical Sensor for Wastewater Monitoring
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作者 Vishal Chaudhary Chethan Muniraju +1 位作者 Helen Merina Albert Pradeep Bhadola 《Electron》 2026年第1期14-24,共11页
The increasing global threat of water pollution demands advanced multilayer sensing technologies with efficacy to detect contaminants with high sensitivity and adaptability in complex aquatic environments.In this theo... The increasing global threat of water pollution demands advanced multilayer sensing technologies with efficacy to detect contaminants with high sensitivity and adaptability in complex aquatic environments.In this theoretical analysis,we investigated a novel multilayer surface plasmon resonance(SPR)system as an optical sensing platform to detect water pollutants and salinity concentrations.The proposed sensor comprised silver,barium borate(BBO),and black phosphorus(BP)layers on a Borokon 7(BK7)prism,which formed a tunable and highly responsive configuration under the Kretschmann geometry.It employed the transfer matrix method(TMM)and angular interrogation in the visible regime to evaluate reflectance spectra and key sensing parameters.The outcomes revealed that the sensor exhibited high sensitivity and selectivity for refractive index(RI)variations corresponding to polluted water samples,including sodium chloride(NaCl)concentrations.The system exhibited strong plasmonic coupling and interfacial interactions,yielding the maximum sensitivity(138.7°/RIU)and figure of merit(73.57 RIU^(-1))toward water samples with 4%NaCl and chemical contamination,respectively.At refractive index of 1.33 and 1.34,by varying the layers of BBO and BP,the maximum sensitivity achieved was 320°/RIU with six BBO layers and a monolayer of BP.These results demonstrated that the proposed SPR sensor configuration,which successfully differentiated between various water quality levels based on refractive index variations,had tremendous potential for next‐generation real‐time water quality monitoring. 展开更多
关键词 black phosphorus Kretschmann configuration sensor surface plasmon resonance transfer matrix water pollution
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Probabilistic distribution and stochastic P-bifurcation of a nonlinear energy-regenerative suspension system with time-delayed feedback control
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作者 Zhao-Bin Zeng Ya-Hui Sun Yang Liu 《Chinese Physics B》 2026年第1期322-330,共9页
Energy-regenerative suspension combined with piezoelectric and electromagnetic transduction has evolved into a core technological pathway in advancing automotive design paradigms.With the aim of improving energy harve... Energy-regenerative suspension combined with piezoelectric and electromagnetic transduction has evolved into a core technological pathway in advancing automotive design paradigms.With the aim of improving energy harvesting performance,time-delayed feedback control is widely used in an energy-regenerative suspension system under different external disturbances in this paper.Meanwhile,limited research has addressed the stochastic dynamics of time-delayed nonlinear energy-regenerative suspension systems.Different from previous studies,this work studies the stochastic response and P-bifurcation of the nonlinear energy-regenerative suspension system with time-delayed feedback control.Firstly,an approximately equivalent dimension reduction system is established by the variable transformation method,and then the stationary probability density function of amplitude is obtained by the stochastic averaging method.Secondly,the precision of the method used in this work is verified by comparing the numerical solutions with the analytical results.Finally,based on the stationary probability density function,the influence of system parameters on stochastic P-bifurcation and the mean output power is discussed. 展开更多
关键词 energy-regenerative suspension stochastic P-bifurcation stochastic resonance time-delayed feedback control
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A bibliometric analysis of publication trends in strabismus over the past 30y
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作者 Yi-Han Zhang Ying Guo +1 位作者 Shu-Jie Zhang Chen Zhao 《International Journal of Ophthalmology(English edition)》 2026年第1期149-159,共11页
AIM:To summarize publication trends in the field of strabismus over the past 30y and predict future research hotspots.METHODS:A total of 2915 English-language articles and reviews on strabismus,published between 1993 ... AIM:To summarize publication trends in the field of strabismus over the past 30y and predict future research hotspots.METHODS:A total of 2915 English-language articles and reviews on strabismus,published between 1993 and 2022,were retrieved from the Web of Science Core Collection.Bibliometric analyses were performed using VOSviewer and CiteSpace software to explore publication trends,as well as the contributions and collaborative networks of countries/regions,authors,institutions,and journals.RESULTS:The annual number of publications on strabismus showed a consistent upward trend.The United States(USA)maintained a leading position in this research field while Republic of Korea and China emerged as rapidly advancing contributors over the last decade.The University of California,Los Angeles ranked as the most productive institution,and Jonathan M.Holmes from USA was the most productive author.Journal of AAPOS was the leading journal with the most strabismus publications,whereas the two most highly cited articles were both published in Ophthalmology.Co-occurrence analysis identified pivotal keywords and burst terms,including intermittent exotropia(IXT),acute acquired comitant esotropia(AACE),functional magnetic resonance imaging(fMRI),and surgical treatment,which were confirmed as predominant and frontier topics.CONCLUSION:This study provides a comprehensive bibliometric analysis of strabismus research,revealing the evolution of research hotspots over the past 30y and outlining several cutting-edge directions for future investigation. 展开更多
关键词 bibliometric analysis STRABISMUS intermittent exotropia strabismus surgery functional magnetic resonance imaging research trends
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