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Pressure-Modulated Activation Energy as a Unified Descriptor of Mechanical Behavior in Metallic Glass
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作者 Huanrong Liu Jian Li +1 位作者 Shan Zhang Pengfei Guan 《Chinese Physics Letters》 2026年第1期71-82,共12页
The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ... The functional properties of glasses are governed by their formation history and the complex relaxation processes they undergo.However,under extreme conditions,glass behaviors are still elusive.In this study,we employ simulations with varied protocols to evaluate the effectiveness of different descriptors in predicting mechanical properties across both low-and high-pressure regimes.Our findings demonstrate that conventional structural and configurational descriptors fail to correlate with the mechanical response following pressure release,whereas the activation energy descriptor exhibits robust linearity with shear modulus after correcting for pressure effects.Notably,the soft mode parameter emerges as an ideal and computationally efficient alternative for capturing this mechanical behavior.These findings provide critical insights into the influence of pressure on glassy properties,integrating the distinct features of compressed glasses into a unified theoretical framework. 展开更多
关键词 pressure modulated activation energy predicting mechanical properties metallic glass relaxation processes functional properties mechanical behavior simulations varied protocols structural configurational descriptors
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Modulated waveforms for harmonic minimization of far-field signals in amplitude-modulated heating of the ionosphere
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作者 ZhiJian Lu Yong Li +6 位作者 Hui Li Jian Wu JingFeng Yao XingBao Lyu ChengXun Yuan ZhongXiang Zhou Ying Wang 《Earth and Planetary Physics》 2025年第2期387-399,共13页
This paper establishes an amplitude modulation heating model, simulating the far-field radiation of ELF/VLF signals generated by modulation heating, as well as the specific location and longitudinal extent of the radi... This paper establishes an amplitude modulation heating model, simulating the far-field radiation of ELF/VLF signals generated by modulation heating, as well as the specific location and longitudinal extent of the radiation source. We consider various modulation waveforms and find that square-wave modulation has the highest excitation efficiency for ELF/VLF signals, and that square-wave modulation with a smaller duty cycle(<50%) exhibits higher excitation efficiency for ELF/VLF signals, while the sin^(2)t waveform modulation yields the lowest proportion of harmonic energy in the generated signals. The amplitude of the second harmonic generated by the sin^(2)t waveform is less than one-tenth that of the fundamental frequency, and the energy of higher-frequency harmonics can be negligibly small compared with those of the fundamental wave. It is a challenging task to achieve a balance between enhancing the excitation efficiency of ELF/VLF signals and also suppressing harmonics generated by the modulated heating process. This is because the harmonics are correspondingly enhanced as the excitation efficiency of the signals is increased. However, we find that under conditions of varying effective radiant power and modulation frequency, as long as the modulation waveform is unchanged, the energy ratio between the fundamental frequency signal generated by modulated heating and each harmonic is relatively fixed, with changes only in signal intensity and the location of the radiation source zone. This implies that one can first select modulation waveforms that make the signal less prone to distortion, then increase the effective radiated power to enhance the signal strength, without concern for harmonic interference of the fundamental signal. 展开更多
关键词 ELF/VLF HARMONIC amplitude-modulated heating modulated waveforms
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Incommensurate modulated structure and its influence on the martensitic transformation temperature span of single phase multielement Ni-Cu-Co-Mn-Ga two-way shape memory single crystals
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作者 Qijia Yu Yang Liu +5 位作者 Chen Si Wenjia Wang Jiaxi Meng Jingmin Wang Jinghua Liu Chengbao Jiang 《Journal of Materials Science & Technology》 2025年第5期230-240,共11页
Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence ... Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence of the martensitic transformation temperature span on Co content was observed.Before training,quite a narrow temperature span of the martensitic transformation,nearly independent of the Co content,was observed in all single crystals.After training the temperature span was still narrow for 8≤x≤10.9 but was obviously expanded for 10.9<x≤12.High-resolution transmission electron microscopy revealed that at the atomic scale,there exists incommensurate modulated structure in the single phase single crystals,as evidenced by nonperiodic satellite spots in the selected area electronic diffraction patterns.Moreover,the modulated wave vector of the satellite spots was increased by higher Co contents.Combining first principal calculations it was considered that the incommensurate modulated structure originates from the formation of Co-Co pairs.After training arrays of ordered dislocations with the same Burgers vector were introduced for 8≤x≤10.9 but the network of dislocations was formed for 10.9<x≤12.Based on analysis of transmission electron microscopy,geometric phase,thermodynamics,and Landau theory,it was considered that the austenite/martensite phase interface was pinned by the network of dislocations,expanding the temperature span of the martensitic transformation.This work supplies new insights for understanding the microstructure and martensitic transformation of Ni-Mn-Ga-based alloys. 展开更多
关键词 Martensitic transformation Incommensurate modulated structure Temperature span DISLOCATION Two-way shape memory effect
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Arginine modulates the pH,microbial composition,and matrix architecture of biofilms from caries-active patients
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作者 Yumi C.Del Rey Pernille D.Rikvold +4 位作者 Marie B.Lund Eero J.Raittio Andreas Schramm Rikke L.Meyer Sebastian Schlafer 《International Journal of Oral Science》 2025年第6期789-797,共9页
The caries-preventive effects of arginine have been attributed to its impact on biofilm composition and pH.Recent in vitro studies suggest that arginine also affects the production of biofilm matrix components that co... The caries-preventive effects of arginine have been attributed to its impact on biofilm composition and pH.Recent in vitro studies suggest that arginine also affects the production of biofilm matrix components that contribute to virulence,but this mechanism has not been investigated clinically.This randomized,placebo-controlled,triple-blind,split-mouth in situ trial assessed arginine's impact on the microbial composition,matrix architecture,and microscale pH of biofilms from caries-active patients(N=10).We also examined whether individual differences in the pH response to arginine were related to biofilm composition and matrix structure.Biofilms were grown for four days on carriers attached to intraoral splints.Three times daily,the biofilms were treated extraorally with sucrose(5 min),followed by arginine or placebo(30 min),in a split-mouth design.After growth,the microscale biofilm p H response to sucrose was monitored by pH ratiometry.Microbial biofilm composition and carbohydrate matrix architecture were analyzed by 16S rRNA gene sequencing and fluorescence lectin-binding analysis,respectively.Arginine treatment significantly mitigated sucrose-induced pH drops,reduced total carbohydrate matrix production,and altered the spatial distribution of fucoseand galactose-containing carbohydrates.Both arginine-and placebo-treated biofilms were dominated by streptococci and Veillonella spp.Paired analyses showed a significant reduction in mitis/oralis group streptococci and a non-significant increase in several arginine metabolizers in arginine-treated biofilms.Individual pH responses were not significantly associated with the abundance of specific bacterial taxa or carbohydrate matrix components.In conclusion,arginine reduced the virulence of biofilms from caries-active patients through multiple mechanisms,including suppressing matrix carbohydrate production. 展开更多
关键词 Arginine modulates the pH and matrix architecture of biofilms from caries-active patients microbial composition
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Correction:NH_(4)^(+)‑Modulated Cathodic Interfacial Spatial Charge Redistribution for High‑Performance Dual‑Ion Capacitors
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作者 Yumin Chen Ziyang Song +2 位作者 Yaokang Lv Lihua Gan Mingxian Liu 《Nano-Micro Letters》 2025年第9期94-94,共1页
Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because th... Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected. 展开更多
关键词 nh modulated cathodic interfacial spatial charge redistribution dual ion capacitors supplementary file correction supplementary file
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High-speed electro-absorption modulated laser
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作者 Zhenyao Li Chen Lyu +5 位作者 Xuliang Zhou Mengqi Wang Haotian Qiu Yejin Zhang Hongyan Yu Jiaoqing Pan 《Journal of Semiconductors》 2025年第11期7-18,共12页
Currently,the global 5G network,cloud computing,and data center industries are experiencing rapid development.The continuous growth of data center traffic has driven the vigorous progress in high-speed optical transce... Currently,the global 5G network,cloud computing,and data center industries are experiencing rapid development.The continuous growth of data center traffic has driven the vigorous progress in high-speed optical transceivers for optical interconnection within data centers.The electro-absorption modulated laser(EML),which is widely used in optical fiber communications,data centers,and high-speed data transmission systems,represents a high-performance photoelectric conversion device.Compared to traditional directly modulated lasers(DMLs),EMLs demonstrate lower frequency chirp and higher modulation bandwidth,enabling support for higher data rates and longer transmission distances.This article introduces the composition,working principles,manufacturing processes,and applications of EMLs.It reviews the progress on advanced indium phosphide(InP)-based EML devices from research institutions worldwide,while summarizing and comparing data transmission rates and key technical approaches across various studies. 展开更多
关键词 electro-absorption modulation high-speed laser modulation bandwidth data transmission rate
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Strain-modulated superconductivity of monolayer Tc_(2)B_(2)
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作者 Zhengtao Liu Zihan Zhang +2 位作者 Hao Song Tian Cui Defang Duan 《Chinese Physics B》 2025年第4期221-227,共7页
Two-dimensional(2D)superconductors have attracted significant research interest due to their promising potential applications in optoelectronic and microelectronic devices.Herein,we employ first-principles calculation... Two-dimensional(2D)superconductors have attracted significant research interest due to their promising potential applications in optoelectronic and microelectronic devices.Herein,we employ first-principles calculations to predicted a new 2D conventional superconductor,Tc_(2)B_(2),demonstrating its stable structural configuration.Remarkably,under biaxial strain,the superconducting transition temperature(T_(c))of Tc_(2)B_(2)demonstrates a significant enhancement,achieving 19.5 K under 3%compressive strain and 9.2 K under 11%tensile strain.Our study reveals that strain-induced modifications in Fermi surface topology significantly enhance the Fermi surface nesting effect,which amplifies electron–phonon coupling interactions and consequently elevates Tc.Additionally,the presence of the Lifshitz transition results in a more pronounced rise in Tc under compressive strain compared to tensile strain.These insights offer important theoretical guidance for designing 2D superconductors with high-Tc through strain modulation. 展开更多
关键词 TWO-DIMENSIONAL SUPERCONDUCTIVITY strain modulation first-principles calculation
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Neurotensin Modulates Emotional Valence Assignment in the Basolateral Amygdala Through Neuromodulator Gain
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作者 Maimaitishalijiang Abudureheman Yu-Hao Xiao +1 位作者 Li-Zang Zeng Hong-Yan Geng 《Neuroscience Bulletin》 2025年第1期177-180,共4页
Based on previous experience,learning to avoid or seek certain specific stimuli again in the future is crucial for survival.Our brains are wired to assign a particular valence-either positive or negativeas a result of... Based on previous experience,learning to avoid or seek certain specific stimuli again in the future is crucial for survival.Our brains are wired to assign a particular valence-either positive or negativeas a result of sensory stimuli,and it is this valence that serves as the foundational motivation for our subsequent actions.Simply put,all motivational actions fall into two categories:pleasure-seeking behavior guided by positive emotional valence,and pain-avoiding behavior driven by negative emotional valence[1].The ability to shift from one emotional valence to another is an important characteristic of affective states,while the instability of emotional states underlies many psychiatric disorders,highlighting the clinical importance of managing and understanding these fluctuations.This ability to adapt emotional responses can be attained by modulating the gain across distinct neural pathways,thus enabling the nuanced and smooth assignment of valence through the strengthening or weakening of circuit activity[1,2]. 展开更多
关键词 EMOTIONAL MOTIVATION MODULATOR
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Dromion structure in(2+1)-dimensional modulated positron-acoustic waves in a non-Maxwellian magnetoplasma
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作者 Aljawhara H Almuqrin Alim +5 位作者 B B Mouhammadoul C G L Tiofack A Mohamadou Sherif M E Ismaeel Weaam Alhejaili S A El-Tantawy 《Communications in Theoretical Physics》 2025年第5期171-183,共13页
This study investigates the dromion structure within the context of(2+1)-dimensional modulated positron-acoustic waves in a magnetoplasma consisting of inertial cold positrons and inertialess nonthermal hot electrons ... This study investigates the dromion structure within the context of(2+1)-dimensional modulated positron-acoustic waves in a magnetoplasma consisting of inertial cold positrons and inertialess nonthermal hot electrons and positrons as well as stationary positive ions.The reductive perturbation approach reduces the fluid governing equations to the plasma model to a Davey–Stewartson system.This study provides a detailed analysis of the influence of many related plasma parameters,including the density ratio of hot and cold positrons,the external magnetic field strength,the nonthermal parameter and the density ratio of electrons and cold positrons,on the growing rate of instability.Using the Hirota Bilinear method,it is found that the system supports some exact solutions,such as one-and two-dromion solutions.The change of plasma parameters significantly enhances the characteristics of dromion solutions.The elastic and inelastic collisions between two dromions are discussed at different times.The relevance of this study can help us to understand the various types of collision between energetic particles in confined plasma during the production of energy by thermonuclear fusion. 展开更多
关键词 Davey-Stewartson equations positron-acoustic waves modulational instability magnetoplasmas dromion soliton
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Active-modulated fluorescence fluctuation super-resolution microscopy with multi-resolution analysis
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作者 Zhijia Liu Duantao Hou +2 位作者 Yiyan Fei Lan Mi Jiong Ma 《Journal of Innovative Optical Health Sciences》 2025年第6期15-26,共12页
A new scheme of super-resolution optical fluctuation imaging(SOFI)is proposed to broaden its application in the high-order cumulant reconstruction by optimizing blinking characteristics,eliminating noise in raw data a... A new scheme of super-resolution optical fluctuation imaging(SOFI)is proposed to broaden its application in the high-order cumulant reconstruction by optimizing blinking characteristics,eliminating noise in raw data and applying multi-resolution analysis in cumulant reconstruction.A motor-driven rotating mask optical modulation system is designed to adjust the excitation lightfield and allows for fast deployment.Active-modulated fluorescence fluctuation superresolution microscopy with multi-resolution analysis(AMF-MRA-SOFI)demonstrates enhanced resolution ability and reconstruction quality in experiments performed on sample of conventional dyes,achieving a resolution of 100 nm in the fourth order compared to conventional SOFI reconstruction.Furthermore,our approach combining expansion super-resolution achieved a resolution at-57 nm. 展开更多
关键词 Super-resolution microscopy SOFI multi-resolution analysis spatial light modulation
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Femtosecond laser modulated into Bessel beam by spatial light modulator for Fresnel zone plate processing
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作者 DUAN Lian ZHOU Fang +3 位作者 KONG De-jian ZHANG Fan SUN Xiao-yan DUAN Ji-an 《Journal of Central South University》 2025年第2期469-482,共14页
Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,... Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,a femtosecond laser Bessel beam is proposed to process micro-FZP,which is modulated from a Gaussian beam to a Bessel annular beam.The processing time for FZP with an outer diameter of 60μm is reduced from 30 min to 1.5 min on an important semiconductor material gallium arsenide(GaAs),which significantly improves the processing efficiency.In the modulation process,a central ablation hole that has an adverse effect on the diffraction performance is produced,and the adverse effect is eliminated by superimposing the blazed grating hologram.Meanwhile,the FZP machined by spatial light modulator(SLM)has good morphology and higher diffraction efficiency,which provides a strong guarantee for the application of micro-FZP in computed tomography and solar photovoltaic cells. 展开更多
关键词 femtosend laser Fresnel zone plate spatial light modulator Bessel beam GAAS
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Sulfur-modulated charge-asymmetry Cu–Zn bimetallic nanoclusters for efficient CO_(2) electroreduction
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作者 Zheng Liu Yin-Qi Li +9 位作者 Yu-Fan Tan Jing-Qiao Zhang Yao Zhu Ting Cao Hai-Yang Lv Hui-Long Geng Ju-Zhe Liu Hua-Zhang Zhai Han Wang Wen-Xing Chen 《Rare Metals》 2025年第9期6211-6222,共12页
CO_(2)electroreduction(CO_(2)RR)represents a promising negative-carbon technology,which is in urgent need for efficient and high-selectivity catalysts.Here,a support control strategy is employed for precise surface en... CO_(2)electroreduction(CO_(2)RR)represents a promising negative-carbon technology,which is in urgent need for efficient and high-selectivity catalysts.Here,a support control strategy is employed for precise surface engineering of charge-asymmetry nanocluster catalyst(CuZnSCN),in which zinc and copper atoms together form a metal cluster loaded on sulfur and nitrogen co-etched carbon matrix.The synergistic promotion mechanism of CO_(2)RR by Cu–Zn atom interactions and sulfur–nitrogen atom doping was investigated.A CO partial current density of 74.1 mA cm^(-2)was achieved in an alkaline electrolyte,as well as a considerable CO Faraday efficiency of 97.7%.In situ XAS(X-ray absorption spectroscopy)showed that the stabilization of Cu^(+)and Zn^(2+)species in the nanoclusters and doped sulfur atoms during the CO_(2)RR process contributes to the sustained adsorption of protons and the generation and conversion of the CO.This work verifies the possibility of metal-support and intermetallic interactions to synergistically enhance electrochemical catalytic performance and provides ideas for further bimetallic cluster catalyst development. 展开更多
关键词 Bimetallic nanoclusters Electronic structure modulation Sulfur-modified carbon substrate CO_(2)electroreduction
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Using Targeted Phonon Excitation to Modulate Thermal Conductivity of Boron Nitride
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作者 Dongkai Pan Tianhao Li +3 位作者 Xiao Wan Zhicheng Zong Yangjun Qin Nuo Yang 《Chinese Physics Letters》 2025年第7期449-453,共5页
Recent advancements in thermal conductivity modulating strategies have shown promising enhancements to the thermal management capabilities of two-dimensional materials.In this article,both the iterative Boltzmann tran... Recent advancements in thermal conductivity modulating strategies have shown promising enhancements to the thermal management capabilities of two-dimensional materials.In this article,both the iterative Boltzmann transport equation solution and the two-temperature model were employed to investigate the efficacy of targeted phonon excitation applied to hexagonal boron nitride(hBN).The results indicate significant modifications to hBN's thermal conductivity,achieving increases of up to 30.1%as well as decreases of up to 59.8%.These findings validate the reliability of the strategy,expand its scope of applicability,and establish it as a powerful tool for tailoring thermal properties across a wider range of fields. 展开更多
关键词 thermal conductivityachieving thermal management capabilities boron nitride targeted phonon excitation iterative boltzmann transport equation solution hexagonal boron nitride hbn thermal conductivity modulating strategies thermal conductivity
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One-step direct ammonia synthesis by pulse-modulated microwave plasma at atmospheric pressure
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作者 Wei WANG Yao LI +5 位作者 Zhaoquan CHEN Sisi LI Yi FENG Zhi ZHENG Dezheng YANG Yue LIU 《Plasma Science and Technology》 2025年第4期112-121,共10页
In this study,we explored a one-step direct synthesis of NH3 under mild experimental conditions utilizing pulse-modulated microwave plasma technology at atmospheric pressure.At a substantial gas flow rate,a microwave ... In this study,we explored a one-step direct synthesis of NH3 under mild experimental conditions utilizing pulse-modulated microwave plasma technology at atmospheric pressure.At a substantial gas flow rate,a microwave plasma jet was formed and the microwave-assisted ammonia synthesis can be realized.Impacts of various parameters including the gas flow rate,gas component,microwave absorbed power,pulse modulation frequency,and pulse duty cycle on ammonia synthesis were systematically investigated.To indicate the reaction path of ammonia synthesis,the distributions of both the gas temperature and active species were also studied using optical emission spectra technology.It is found that a considerable amount of ammonia was directly synthesized without involvement of any catalysts,the highest ammonia production rate and energy efficiency(EE),up to 2.93μmol·min^(-1) and 6.64×10^(-2)g·(k W·h)^(-1),respectively,were achieved under low microwave power of 84.42 W.The duty cycle has obvious influences on the synthesis efficiency,compared to a duty cycle of 80%,the ammonia synthesis rate,EE and nitrogen conversion decreased by about 22%at a duty cycle of 100%.This finding underscores the significance of incorporating pulse modulation in the microwave discharge process for ammonia synthesis.Furthermore,it was found that vibrational excitation of microwave plasma has a significant driving effect on ammonia synthesis. 展开更多
关键词 microwave plasma ammonia synthesis pulse modulation plasma jet microwave resonant cavity(Some figures may appear in colour only in the online journal)
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Simultaneous modulated accelerated radiation therapy for esophageal cancer:A feasibility study 被引量:12
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作者 Wu-Zhe Zhang Jian-Zhou Chen +6 位作者 De-Rui Li Zhi-Jian Chen Hong Guo Ting-Ting Zhuang Dong-Sheng Li Ming-Zhen Zhou Chuang-Zhen Chen 《World Journal of Gastroenterology》 SCIE CAS 2014年第38期13973-13980,共8页
AIM: To establish the feasibility of simultaneous modulated accelerated radiation therapy (SMART) in esophageal cancer (EC).
关键词 Simultaneous modulated accelerated radiation therapy Three-dimensional conformal radiotherapy Intensity-modulated radiation therapy Esophageal cancer FEASIBILITY
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Dosimetry Comparison between Volumetric Modulated Arc Therapy with RapidArc and Fixed Field Dynamic IMRT for Local-Regionally Advanced Nasopharyngeal Carcinoma 被引量:8
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作者 Bao-min Zheng Xiao-xia Dong +3 位作者 Hao Wu You-jia Duan Shu-kui Han Yan Sun 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2011年第4期259-264,共6页
Objective: A dosimetric study was performed to evaluate the performance of volumetric modulated arc radiotherapy with RapidArc on locally advanced nasopharyngeal carcinoma (NPC). Methods: The CT scan data sets of 20 p... Objective: A dosimetric study was performed to evaluate the performance of volumetric modulated arc radiotherapy with RapidArc on locally advanced nasopharyngeal carcinoma (NPC). Methods: The CT scan data sets of 20 patients of locally advanced NPC were selected randomly. The plans were managed using volumetric modulated arc with RapidArc and fixed nine-field coplanar dynamic intensity-modulated radiotherapy (IMRT) for these patients. The dosimetry of the planning target volumes (PTV), the organs at risk (OARs) and the healthy tissue were evaluated. The dose prescription was set to 70 Gy to the primary tumor and 60 Gy to the clinical target volumes (CTV) in 33 fractions. Each fraction applied daily, five fractions per week. The monitor unit (MU) values and the delivery time were scored to evaluate the expected treatment efficiency. Results: Both techniques had reached clinical treatment’s requirement. The mean dose (Dmean), maximum dose (Dmax) and minimum dose (Dmin) in RapidArc and fixed field IMRT for PTV were 68.4±0.6 Gy, 74.8±0.9 Gy and 56.8±1.1 Gy; and 67.6±0.6 Gy, 73.8±0.4 Gy and 57.5±0.6 Gy (P<0.05), respectively. Homogeneity index was 78.85±1.29 in RapidArc and 80.34±0.54 (P<0.05) in IMRT. The conformity index (CI: 95%) was 0.78±0.01 for both techniques (P>0.05). Compared to IMRT, RapidArc allowed a reduction of Dmean to the brain stem, mandible and optic nerves of 14.1% (P<0.05), 5.6% (P<0.05) and 12.2% (P<0.05), respectively. For the healthy tissue and the whole absorbed dose, Dmean of RapidArc was reduced by 3.6% (P<0.05), and 3.7% (P<0.05), respectively. The Dmean to the parotids, the spinal cord and the lens had no statistical difference among them. The mean MU values of RapidArc and IMRT were 550 and 1,379. The mean treatment time of RapidArc and IMRT was 165 s and 447 s. Compared to IMRT, the delivery time and the MU values of RapidArc were reduced by 63% and 60%, respectively. Conclusion: For locally advanced NPC, both RapidArc and IMRT reached the clinic requirement. The target volume coverage was similar for the different techniques. The RapidArc technique showed some improvements in OARs and other tissue sparing while using reduced MUs and delivery time. 展开更多
关键词 Volumetric modulated arc therapy Intensity-modulated radiotherapy DOSIMETRY Target volume Nasopharyngeal carcinoma
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Helical tomotherapy and volumetric modulated arc therapy:New therapeutic arms in the breast cancer radiotherapy 被引量:7
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作者 Olivier Lauche Youlia M Kirova +8 位作者 Pascal Fenoglietto Emilie Costa Claire Lemanski Celine Bourgier Olivier Riou David Tiberi Francois Campana Alain Fourquet David Azria 《World Journal of Radiology》 CAS 2016年第8期735-742,共8页
AIM To analyse clinical and dosimetric results of helical tomotherapy(HT)and volumetric modulated arc therapy(VMAT)in complex adjuvant breast and nodes irradiation.METHODS Seventy-three patients were included(31 HT an... AIM To analyse clinical and dosimetric results of helical tomotherapy(HT)and volumetric modulated arc therapy(VMAT)in complex adjuvant breast and nodes irradiation.METHODS Seventy-three patients were included(31 HT and 42 VMAT).Dose were 63.8 Gy(HT)and 63.2 Gy(VMAT)in the tumour bed,52.2 Gy in the breast,50.4 Gy in supraclavicular nodes(SCN)and internal mammary chain(IMC)with HT and 52.2 Gy and 49.3 Gy in IMC and SCN with VMAT in 29 fractions.Margins to particle tracking velocimetry were greater in the VMAT cohort(7 mm vs 5 mm).RESULTS For the HT cohort,the coverage of clinical target volumes was as follows:Tumour bed:99.4%±2.4%;breast:98.4%±4.3%;SCN:99.5%±1.2%;IMC:96.5%±13.9%.For the VMAT cohort,the coverage was as follows:Tumour bed:99.7%±0.5%,breast:99.3%±0.7%;SCN:99.6%±1.4%;IMC:99.3%±3%.For ipsilateral lung,Dmean and V20 were 13.6±1.2 Gy,21.1%±5%(HT)and 13.6±1.4 Gy,20.1%±3.2%(VMAT).Dmean and V30 of the heart were 7.4±1.4 Gy,1%±1%(HT)and 10.3±4.2 Gy,2.5%±3.9%(VMAT).For controlateral breast Dmean was 3.6±0.2 Gy(HT)and 4.6±0.9 Gy(VMAT).Acute skin toxicity grade 3 was 5%in the two cohorts.CONCLUSION HT and VMAT in complex adjuvant breast irradiation allow a good coverage of target volumes with an acceptable acute tolerance.A longer follow-up is needed to assess the impact of low doses to healthy tissues. 展开更多
关键词 Three-dimensional conformal radiotherapy Intensity modulated radiation therapy TOXICITY Helical tomotherapy Volumetric modulated arc therapy Breast cancer radiotherapy
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On approximating multifractal traffic burstiness with Markov modulated Poisson processes 被引量:1
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作者 纪其进 《Journal of Southeast University(English Edition)》 EI CAS 2004年第4期436-441,共6页
We investigate the approximating capability of Markov modulated Poisson processes (MMPP) for modeling multifractal Internet traffic. The choice of MMPP is motivated by its ability to capture the variability and correl... We investigate the approximating capability of Markov modulated Poisson processes (MMPP) for modeling multifractal Internet traffic. The choice of MMPP is motivated by its ability to capture the variability and correlation in moderate time scales while being analytically tractable. Important statistics of traffic burstiness are described and a customized moment-based fitting procedure of MMPP to traffic traces is presented. Our methodology of doing this is to examine whether the MMPP can be used to predict the performance of a queue to which MMPP sample paths and measured traffic traces are fed for comparison respectively, in addition to the goodness-of-fit test of MMPP. Numerical results and simulations show that the fitted MMPP can approximate multifractal traffic quite well, i.e. accurately predict the queueing performance. 展开更多
关键词 multifractal traffic Markov modulated Poisson processes queueing delay packet loss rate
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Clinical role of ^(18)F-FDG PET/CT-based simultaneous modulated accelerated radiotherapy treatment planning for locally advanced nasopharyngeal carcinoma 被引量:1
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作者 Jianshe Wang Tianyou Tang +4 位作者 Jing Xu Andrew Z.Wang Liang Li Junnian Zheng Longzhen Zhang 《Oncology and Translational Medicine》 2015年第6期264-270,共7页
Objective The aim of this study was to compare the long-term local control, overall survival, and late toxicities of positron emission tomography/computed tomography (PET/CT)-guided dose escalation radio- therapy ve... Objective The aim of this study was to compare the long-term local control, overall survival, and late toxicities of positron emission tomography/computed tomography (PET/CT)-guided dose escalation radio- therapy versus conventional radiotherapy in the concurrent chemoradiotherapy treatment of locally ad- vanced nasopharyngeal carcinoma (NPC). Methods Atotal of 48 patients with stage IIl-IVa NPC were recruited and randomly administered PET/CT- guided dose escalation chemoradiotherapy (group A) or conventional chemoradiotherapy (group B). The dose-escalation radiotherapy was performed using the simultaneous modulated accelerated radiotherapy technique at prescribed doses of 77 gray (Gy) in 32 fractions (f) to the gross target volume (GTV): planning target volume (PTV) 1 received 64 Gy/32 f, while PTV2 received 54.4 Gy/32 f. Patients in group B received uniform-dose intensity-modulated radiotherapy, PTV1 received 70 Gy/35 f and PTV2 received 58 Gy/29 f. Concurrent chemotherapy consisted of cisplatin [20 mg/m2 intravenous (IV) on days 1-4] and docetaxel (75 mg/m2 IV on days 1 and 8) administered during treatment weeks 1 and 4. All patients received 2-4 cycles of adjuvant chemotherapy of the same dose and drug regimen. Results The use of fluorine-18-fluorodeoxyglucose (18F-FDG) PET/CT significantly reduced the treat- ment volume delineation of the GTV in 83.3% (20/24) of patients. The 5-year local recurrence-free survival rates of the two groups were 100% and 79.2%, respectively (P = 0.019). The 5-year disease free survival (DFS) rates were 95.8% and 75.0%, respectively (P = 0.018). The 5-year local progression-free survival and DFS rates were significantly different. The 5-year overall survival (OS) rates were 95.8% and 79.2%, re- spectively. Differences in OS improvement were insignificant (P = 0.079). Late toxicities were similar in the two groups. The most common late toxicities of the two arms were grade 1-2 skin dystrophy, xerostomia, subcutaneous fibrosis, and hearing loss. There were no cases of grade 4 late toxicity. Conclusion The use of 18F-FDG PET/CT-guided dose escalation radiotherapy is well tolerated and can reduce local recurrence rates for patients with locally advanced NPC compared to conventional chemora- diotherapy. 展开更多
关键词 nasopharyngeal carcinoma (NPC) simultaneous modulated accelerated radiotherapy in-tensity-modulated radiotherapy positron emission tomography/computed tomography (PET/CT) fluorine-18-fluorodeoxyglucose (18F-FDG)
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Cosine-modulated window function-based staggered-grid finite-difference forward modeling 被引量:5
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作者 王建 孟小红 +2 位作者 刘洪 郑婉秋 贵生 《Applied Geophysics》 SCIE CSCD 2017年第1期115-124,191,共11页
The numerical dispersion and computational cost are high for conventional Taylor series expansion staggered-grid finite-difference forward modeling owing to the high frequency of the wavelets and the large grid interv... The numerical dispersion and computational cost are high for conventional Taylor series expansion staggered-grid finite-difference forward modeling owing to the high frequency of the wavelets and the large grid intervals. In this study, the cosine-modulated binomial window function (CMBWF)-based staggered-grid finite-difference method is proposed. Two new parameters, the modulated time and modulated range are used in the new window function and by adjusting these two parameters we obtain different characteristics of the main and side lobes of the amplitude response. Numerical dispersion analysis and elastic wavefield forward modeling suggests that the CMBWF method is more precise and less computationally costly than the conventional Taylor series expansion staggered-grid finite-difference method. 展开更多
关键词 Elastic wave staggered grid window function cosine modulate
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