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Framework for Secure Substitution Box Construction and Its Application in Image Encryption
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作者 Umar Hayat Ikram Ullah Muhammad Bilal 《Computers, Materials & Continua》 2026年第4期1428-1462,共35页
Elliptic curve(EC)based cryptosystems gained more attention due to enhanced security than the existing public key cryptosystems.A substitution box(S-box)plays a vital role in securing modern symmetric key cryptosystem... Elliptic curve(EC)based cryptosystems gained more attention due to enhanced security than the existing public key cryptosystems.A substitution box(S-box)plays a vital role in securing modern symmetric key cryptosystems.However,the recently developed EC based algorithms usually trade off between computational efficiency and security,necessitating the design of a new algorithm with the desired cryptographic strength.To address these shortcomings,this paper proposes a new scheme based onMordell elliptic curve(MEC)over the complex field for generating distinct,dynamic,and highly uncorrelated S-boxes.Furthermore,we count the exact number of the obtained S-boxes,and demonstrate that the permuted version of the presented S-box is statistically optimal.The nonsingularity of the presented algorithm and the injectivity of the resultant output are explored.Rigorous theoretical analysis and experimental results demonstrate that the proposedmethod is highly effective in generating a large number of dynamic S-boxes with adequate cryptographic properties,surpassing current state-of-the-art S-box generation algorithms in terms of security.Apart fromthis,the generated S-box is benchmarked using side-channel attacks,and its performance is compared with highly nonlinear S-boxes,demonstrating comparable results.In addition,we present an application of our proposed S-box generator by incorporating it into an image encryption technique.The encrypted and decrypted images are tested by employing extensive standard security metrics,including the Number of Pixel Change Rate,the Unified Average Changing Intensity,information entropy,correlation coefficient,and histogram analysis.Moreover,the analysis is extended beyond conventional metrics to validate the new method using advanced tests,such as the NIST statistical test suite,robustness analysis,and noise and cropping attacks.Experimental outcomes show that the presented algorithm strengthens the existing encryption scheme against various well-known cryptographic attacks. 展开更多
关键词 Substitution box Mordell elliptic curve Mobius transformation NONLINEARITY image encryption CRYPTANALYSIS data security
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Mechanical-thermal coupling model and fatigue life analysis of axle-box bearings of high-speed train
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作者 Weixu Zhao Yongqiang Liu +2 位作者 Baosen Wang Shaopu Yang Yingying Liao 《Chinese Journal of Mechanical Engineering》 2026年第1期548-562,共15页
The axle box bearings of high-speed trains often operate in extremely harsh environments,bearing loads from different directions.Long-term operation and frequent changes in working conditions can easily lead to axle b... The axle box bearings of high-speed trains often operate in extremely harsh environments,bearing loads from different directions.Long-term operation and frequent changes in working conditions can easily lead to axle box bearing failures.Therefore,it is extremely important to study the mechanism of axle box bearings.Firstly,the medium of thermal deformation establishes a coupling relationship between the system dynamics model and the thermal grid model,and then obtains the thermal force coupling model of the high-speed train axle box bearing.The coupling model is validated from the perspectives of system dynamics response and temperature response,proving its effectiveness in system dynamics response and temperature characteristic response.Comparing the coupling model with the dynamics model,it is found that thermal deformation complicates the dynamic re-sponse.Finally,using the Lundberg-Palmgren(L-P)bearing fatigue calculation method and damage accumu-lation theory,the bearing fatigue life is calculated,and it is found that thermal deformation deteriorates the bearing operating environment,reducing the bearing fatigue life.Finally,by comparing the bearing fatigue life under different working conditions,it is concluded that the faster the vehicle speed,the greater the load,and the smaller the initial radial clearance of the bearing,the fatigue life of the bearing is reduced.The shorter the lifespan. 展开更多
关键词 High-speed train Axle box bearing Mechanical-thermal coupling model Fatigue life
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Seismic performance of double- skin steel- concrete composite box piers: Part Ⅰ——Bidirectional quasi-static testing 被引量:7
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作者 夏坚 宗周红 +1 位作者 徐焯然 李明鸿 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期58-66,共9页
To study the seismic performance of double-skin steelconcrete composite box( DSCB) piers, a total of 11 DSCB pier specimens were tested under bidirectional cyclic loading. The effects of the loading pattern, the ste... To study the seismic performance of double-skin steelconcrete composite box( DSCB) piers, a total of 11 DSCB pier specimens were tested under bidirectional cyclic loading. The effects of the loading pattern, the steel plate thickness, the axial load ratio, the slenderness ratio and the aspect ratio were taken into consideration. The damage evolution process and failure modes of the tested specimens are presented in detail. Test results are also discussed in terms of the hysteretic curve, skeleton curve, ductility and energy dissipation capacity of DSCB pier specimens. It can be concluded that the hysteretic performance of DSCB piers in one direction is affected and weakened by the cyclic loading in the other direction. DSCB piers under bidirectional cyclic loading exhibit good performance in terms of load carrying capacity, ductility, and energy dissipation capacity. Overall, DSCB piers can meet the basic aseismic requirements. The research results can be taken as a reference for using DSCB piers as high piers in bridges in strong earthquakeprone areas. 展开更多
关键词 double-skin steel-concrete composite box(DSCB) pier bidirectional quasi-static testing hysteretic curve skeleton curve ductility energy dissipation capacity
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Seismic performance of double-skin steel-concrete composite box piers: Part Ⅱ—Nonlinear finite element analysis
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作者 夏坚 宗周红 +1 位作者 徐焯然 李明鸿 《Journal of Southeast University(English Edition)》 EI CAS 2016年第3期346-355,共10页
An accurate finite element ( FE) model was constructed to examine the hysteretic behavior of double-skin steel-concrete composite box ( DSCB) piers for further understanding the seismic performance of DSCB piers;... An accurate finite element ( FE) model was constructed to examine the hysteretic behavior of double-skin steel-concrete composite box ( DSCB) piers for further understanding the seismic performance of DSCB piers; where the local buckling behavior of steel tubes, the confinement of the in-filled concrete and the interface action between steel tube and in-filled concrete were considered. The accuracy of the proposed FE model was verified by the bidirectional cyclic loading test results. Based on the validated FE model, the effects of some key parameters, such as section width to steel thickness ratio, slenderness ratio, aspect ratio and axial load ratio on the hysteretic behavior of DSCB piers were investigated. Finally, the skeleton curve model of DSCB piers was proposed. The numerical simulation results reveal that the peak strength and elastic stiffness decrease with the increase of the section width to steel thickness ratio. Moreover, the increase of the slenderness ratio may result in a significant reduction in the peak strength and elastic stiffness while the ultimate displacement increases. The proposed skeleton curve model can be taken as a reference for seismic performance analyses of the DSCB piers. 展开更多
关键词 double-skin steel-concrete composite box(DSCB) pier finite element analysis local buckling hysteretic behavior skeleton curve model
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Formulation optimization of scutellarin-loaded HP-β-CD/chitosan nanoparticles using response surface methodology with Box–Behnken design 被引量:4
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作者 Shanshan Liu Paul C.Ho 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第4期378-385,共8页
The aim of this paper is to investigate and optimize the preparation of scutellarin(SCU)-loaded HP-β-CD/chitosan(CS) nanoparticles(CD/CS-SCU-NPs). CD/CS-SCU-NPs were prepared by ionic cross-linking method and the pro... The aim of this paper is to investigate and optimize the preparation of scutellarin(SCU)-loaded HP-β-CD/chitosan(CS) nanoparticles(CD/CS-SCU-NPs). CD/CS-SCU-NPs were prepared by ionic cross-linking method and the process and formulation variables were optimized using response surface methodology(RSM) with a three-level, three factor Box–Behnken design(BBD).The independent variables were the added amounts of CS, sodium tripolyphosphate(TPP)and Pluronic F-68 during the preparation. Dependent variables(responses) were particle size and entrapment efficiency. Mathematical equations and respond surface plots were used to correlate independent and dependent variables.The preparation process and formulation variables were optimized to achieve minimum particle size and maximum entrapment efficiency by calculating the overall desirability value(OD). The optimized NP formulation was characterized for particle size, PDI, zeta potential, entrapment efficiency and in vitro drug release.According to the results, an optimized CD/CS-SCU-NP formulation was prepared. Results for particle size, PDI, zeta potential and entrapment efficiency were found to be around 200 nm,0.5, 25 mV, and 70% respectively. For in vitro study, the release of SCU from the NPs exhibited a biphasic release and was in accordance with Higuchi equation. The optimized preparation was simple with the probability for industrialization. The combination use of RSM, BBD and overall desirability values could provide a promising application for incorporating CD into CS nanoparticles as drug delivery carrier and help develop lab-scale procedures. 展开更多
关键词 SCUTELLARIN Response surface methodology box–Behnken DESIGN CHITOSAN HP-β-CD Nanoparticles
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Quantum Charged Particle in a Flat Box under Static Electromagnetic Field with Landau’s Gauge and Special Case with Symmetric Gauge 被引量:2
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作者 Gustavo V. López Jorge A. Lizarraga Omar J. P. Bravo 《Journal of Modern Physics》 2021年第10期1464-1474,共11页
We summarize our results about the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field with Landau’s gauge for the magnetic field, where Fourier’s transforma... We summarize our results about the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field with Landau’s gauge for the magnetic field, where Fourier’s transformation was used to analyze the problem, to point out that there exists a wave function which is different to that one given by Landau with the same Landau’s levels. The quantization of the magnetic flux is deduced differently to previous one, and a new solution is presented for the case of symmetric gauge of the magnetic field, and having the same Landau’s levels. 展开更多
关键词 Landau’s Gauge Symmetric Gauge Quantum Hall Effect Flat box
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Factors Affecting Box Office during Broad Spring Festival Based on Partial Least Squares Regression
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作者 ZHAO Xinxing SHI Chaoyue ZHAO Jiashuai 《Journal of Donghua University(English Edition)》 EI CAS 2019年第6期594-598,共5页
The box office during the later Spring Festival shows an attractive prospect.This paper studied the factors affecting total box office during the broad Spring Festival which is from the Spring Festival to the Lantern ... The box office during the later Spring Festival shows an attractive prospect.This paper studied the factors affecting total box office during the broad Spring Festival which is from the Spring Festival to the Lantern Festival.Data of films released during the broad Spring Festival from the years 2016 to 2019 in China were gathered,and the impact of eight explanatory variables on the box office during the broad Spring Festival was empirically analyzed by partial least squares(PLS)regression with software SIMCA.The results suggest that word-of-mouth has the most positive effect on the box office during the broad Spring Festival.Later propaganda has a positive effect,while early promotion has a negative effect on the box office.Director’s influence has a positive effect,while actor’s influence does not contribute much to the box office.Length of the trailer has a negative effect.The film format of 2D or 3D doesn’t contribute much to the box office. 展开更多
关键词 box office the BROAD Spring FESTIVAL partIAL least squares(PLS)
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Dynamics of Particle in a Box in Time Varying Potential Due to Chirped Laser Pulse
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作者 Brijender Dahiya Vinod Prasad 《Journal of Modern Physics》 2010年第6期372-378,共7页
We describe a computational method for simulating the time dependent quantum mechanical system inter-acting with external field. In this method the Schr?dinger equation is solved by expanding the wave function in the ... We describe a computational method for simulating the time dependent quantum mechanical system inter-acting with external field. In this method the Schr?dinger equation is solved by expanding the wave function in the basis set of unperturbed Hamiltonian. The expansion yields a set of coupled first order differential equation. For expansion coefficients, the coupled channel method is applied to a particle in a box interacting with external field in the form of chirped laser pulse. The pulse shape is taken as Gaussian. We study the ef-fect of different pulse parameters i.e. chirp rate, intensity, center frequency, box length and laser duration on the dynamics of the particle. Many interesting results are obtained and explained. 展开更多
关键词 Transition PROBABILITY CHIRP Rate box LENGTH
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Charged Particle in a Flat Box with Static Electromagnetic Field and Landau’s Levels
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作者 Gustavo V. López Jorge A. Lizarraga 《Journal of Modern Physics》 2020年第10期1731-1742,共12页
We study the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field. Contrary to Landau’s solution with constant magnetic field transverse to the box and using F... We study the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field. Contrary to Landau’s solution with constant magnetic field transverse to the box and using Fourier transformation, we found a full solution for the wave function which is different from that one given by Landau, and this fact remains when static electric field is added. However, the Landau’s levels appear in all cases. 展开更多
关键词 Landau’s Levels Quantum Hall Effect Flat box
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Enhancing box-wing design efficiency through machine learning based optimization 被引量:1
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作者 Mehedi HASAN Azad KHANDOKER 《Chinese Journal of Aeronautics》 2025年第2期46-59,共14页
The optimization of wings typically relies on computationally intensive high-fidelity simulations,which restrict the quick exploration of design spaces.To address this problem,this paper introduces a methodology dedic... The optimization of wings typically relies on computationally intensive high-fidelity simulations,which restrict the quick exploration of design spaces.To address this problem,this paper introduces a methodology dedicated to optimizing box wing configurations using low-fidelity data driven machine learning approach.This technique showcases its practicality through the utilization of a tailored low-fidelity machine learning technique,specifically designed for early-stage wing configuration.By employing surrogate model trained on small dataset derived from low-fidelity simulations,our method aims to predict outputs within an acceptable range.This strategy significantly mitigates computational costs and expedites the design exploration process.The methodology's validation relies on its successful application in optimizing the box wing of PARSIFAL,serving as a benchmark,while the primary focus remains on optimizing the newly designed box wing by Bionica.Applying this method to the Bionica configuration led to a notable 14%improvement in overall aerodynamic effciency.Furthermore,all the optimized results obtained from machine learning model undergo rigorous assessments through the high-fidelity RANS analysis for confirmation.This methodology introduces innovative approach that aims to streamline computational processes,potentially reducing the time and resources required compared to traditional optimization methods. 展开更多
关键词 box wing optimization Aerodynamic shape optimization Multi-objective optimization Machine learning Multi-fidelity method
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多媒介视角下的美术教育文化——以Master box课程为例
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作者 汪菲 《美术教育研究》 2025年第17期76-79,共4页
该文探讨多媒介视角下的美术教育文化,以Masterbox课程为例,强调当代艺术界限模糊、美术教育培养鉴赏力与创造力的重要性。教师结合空间转向理论,通过逆向思考培养学生的空间感知与表达能力,探讨“经营位置”、空间“层叠建构”、透明... 该文探讨多媒介视角下的美术教育文化,以Masterbox课程为例,强调当代艺术界限模糊、美术教育培养鉴赏力与创造力的重要性。教师结合空间转向理论,通过逆向思考培养学生的空间感知与表达能力,探讨“经营位置”、空间“层叠建构”、透明性理论等Masterbox课程中用到的空间概念,并列举三组作品,通过模型、视频、交互等形式加以展示。课程成果面向专业学生和公众,能够提升公众的艺术认知,为当代美术教育提供新的视角和方法。 展开更多
关键词 多媒介 美育推广 Master box课程 空间转向 公众艺术认知
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High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation
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作者 Hanki Kim Bum Jun Kim +4 位作者 Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim Jun Young Choi 《Neural Regeneration Research》 SCIE CAS 2025年第1期107-115,共9页
High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the ex... High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1. 展开更多
关键词 central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 INFLAMMATION neural stem cells NEURODEVELOPMENT oligodendrocyte progenitor cells redox status REGENERATION
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Multi-Dimensional Parachute Deployment Box for Mars Precision Landing
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作者 XING Zhehao LIANG Zixuan 《深空探测学报(中英文)》 北大核心 2025年第6期629-638,共10页
The parachute deployment conditions during the terminal entry phase in Mars landing missions exhibit critical impact on landing precision.In this article,aiming at the requirements of safe parachute deployment and acc... The parachute deployment conditions during the terminal entry phase in Mars landing missions exhibit critical impact on landing precision.In this article,aiming at the requirements of safe parachute deployment and accurate landing,a multidimensional parachute deployment box for determining deployment condition during Mars landing was proposed.First,an extremerange optimization model was established,synthesizing the dynamics and constraints of both parachute descent and powered descent phases.Then,on the basis of the two-dimensional altitude-velocity deployment box,a multi-dimensional parachute deployment box characterized by altitude,velocity,flight-path angle,and extreme range was constructed through the integration of extreme range information.Furthermore,an evaluation index for landing precision was formulated and a deployment control logic was proposed for minimizing landing deviation.Finally,the proposed deployment box was simulated in a Mars landing mission.The results demonstrate that the proposed box effectively satisfies safe deployment and landing precision demands,eliminating the range-to-go error at the terminal of the entry phase. 展开更多
关键词 Mars exploration precision landing multiple constraints parachute deployment box parachute deployment control
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Dynamic modeling and simulation of irregular faults in axle box bearings of high-speed trains
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作者 Xiaohui GU Yajia WANG +2 位作者 Pengfei LIU Zechao LIU Shaopu YANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第10期1883-1902,共20页
Axle box bearings are critical components of high-speed trains.Localized defects,such as pitting and spalling,on raceways or rollers pose significant threats to the operational safety of railway vehicles.In this work,... Axle box bearings are critical components of high-speed trains.Localized defects,such as pitting and spalling,on raceways or rollers pose significant threats to the operational safety of railway vehicles.In this work,a novel bearing-flexible axle boxvehicle coupling model is established to explore the vibration characteristics of axle box bearings with irregular localized defects.First,based on the contact and kinematic relationship between rollers and raceways,the three-dimensional(3D)bearing force elements are analyzed and formulated.Second,the established model and a flexible axle box are integrated into the vehicle,and the responses of the normal and faulty bearings under the combined excitations of wheel roughness and track irregularities are simulated.Third,the simulation results are verified through a rolling-vibrating test bench for full-scale wheelsets of high-speed trains.The comparisons of the fault-induced repetitive transients in the time-domain and the fault characteristic frequencies in the envelope spectra demonstrate the efficiency of the proposed model.Finally,based on the flexible axle box model,a sensitivity analysis of the accelerometer placements to the bearing faults is carried out,and the optimal one is identified based on both the time-domain and frequency-domain signal-to-noise ratios(SNRs)for engineering applications. 展开更多
关键词 axle box bearing irregular fault track irregularity flexible axle box accelerometer placement selection
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Investigation of high-mobility group box 1 variants with lymph node status and colorectal cancer risk
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作者 Xin Liu Sheng Zhang +4 位作者 Hao Qiu Zhi-Qiang Xie Wei-Feng Tang Yu Chen Xi Wei 《World Journal of Gastrointestinal Oncology》 2025年第4期67-80,共14页
BACKGROUND Accumulating studies indicated that maintain nuclei homeostasis was deemed to the protective factors for the occurrence of cancer.Thus,high-mobility group box 1(HMGB1)might influence the risk and poorer pro... BACKGROUND Accumulating studies indicated that maintain nuclei homeostasis was deemed to the protective factors for the occurrence of cancer.Thus,high-mobility group box 1(HMGB1)might influence the risk and poorer prognoses of colorectal cancer(CRC).AIM This study was designed to investigate whether HMGB1 polymorphisms influence the risk and lymph node metastasis(LNM)of CRC.METHODS Firstly,we designed an investigation with 1003 CRC patients and 1303 cancer-free controls to observe whether HMGB1 rs1412125 T>C and rs1045411 C>T SNPs could influence the risk of cancer.Subsequently,we carried out a correlation-analysis to assess whether these SNPs could alter the risk of LNM.RESULTS The current investigation suggested a relationship of HMGB1 rs1412125 SNP with the increased susceptibility of CRC.In a subgroup analysis,our findings suggested that this SNP could enhance an occurrence of CRC in≥61 years,non-drinker and body mass index<24 kg/m2 subgroups.However,we found that there was null association between HMGB1 rs1412125 SNP and LNM,even in different CRC region.These observations were confirmed by calculating the power value(more than 0.8).The association of HMGB1 rs1045411 C>T SNP with CRC risk and LNM was not found in any compare.CONCLUSION This study highlights a possible association between HMGB1 rs1412125 polymorphism and the increased risk of CRC.In the future,more studies should be conducted to explore HMGB1 rs1412125 polymorphism in relation to CRC development. 展开更多
关键词 High-mobility group box 1 Colorectal cancer POLYMORPHISM Immune Lymph nodes metastasis
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Effect of the Aspect Ratio of Box Girders on the Buffeting Response of Long-Span Suspension Bridges
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作者 Jingxiang Zhou Qiaoling Zhou +3 位作者 Chunlian Liang Yulu Guo Zhao Xiao Yingfeng Xu 《Structural Durability & Health Monitoring》 2025年第4期953-983,共31页
Streamlined box girders serve as a prevalent choice for the primary structural elements in large-span suspension bridge designs.With the increase in traffic demands,the design of such girders is evolving towards wider... Streamlined box girders serve as a prevalent choice for the primary structural elements in large-span suspension bridge designs.With the increase in traffic demands,the design of such girders is evolving towards wider bridge decks and larger aspect ratios(B/D).To obtain more effective and aerodynamic design shapes for streamlined box girders,it is essential to investigate the impact of B/D on their aerodynamic performance.Accordingly,in this study we investigate the buffeting responses of large-span suspension bridges using girders of varying aspect ratios(B/D of 7.5,9.3,and 12.7).First,the aerodynamic coefficients of these girders are estimated using computational fluid dynamics(CFD)simulations.Subsequently,spatial finite element(FE)models of three long-span suspension bridges with different girders(B/D of 7.5,9.3,and 12.7)are established in Ansys software,and the dynamic characteristics of these bridges are obtained.Then,the time-domain buffeting analysis is performed by simulating the fluctuating wind fields acting on the bridge through the spectral representation method.Ultimately,the buffeting responses are computed using Ansys software,and the impact of B/D on these responses is assessed.The results reveal that the root mean square(RMS)values of the main girder’s buffeting displacement are highest at the midspan position and are lowest at the ends of the bridge.A decrease in B/D of the main girder leads to a more severe buffeting response because both the range and the effective value of the displacement increase with the decreasing B/D.Comparing the buffeting displacements in three directions,B/D plays a significant role in the vertical buffeting displacement,moderately impacts the torsional displacement,and has the least effect on the lateral displacement.The findings of this study may help wind resistance analysis and design optimization for bridges. 展开更多
关键词 Long-span suspension bridge buffeting response aspect ratio streamlined box girder turbulent flow
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Hydration Heat Analysis and Crack Control of Composite Box Girders with Corrugated Steel Webs in Prefabrication
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作者 Xuefeng Wang Haiqing Cao +2 位作者 Ke Jiao Aoxiang Li Zhongwei Li 《Structural Durability & Health Monitoring》 2025年第4期985-1010,共26页
This study examines the temperature field distribution characteristics and temperature effects during the prefabrication of composite box girders with corrugated steel webs(CBGCSWs),aiming to provide practical recomme... This study examines the temperature field distribution characteristics and temperature effects during the prefabrication of composite box girders with corrugated steel webs(CBGCSWs),aiming to provide practical recommendations for controlling temperature-induced cracking and technical guidance for concrete mix proportions and placement processes.Based on field measurement data,a three-dimensional finite element model was developed to simulate the temperature effects at critical locations during the prefabrication phase.By varying the concrete mix proportions,initial casting temperature,and ambient temperature,the study elucidates the variation patterns of the temperature field during precast placement.The results show that the temperature rise caused by hydration heat increases with higher cement and fly ash content,whereas reducing cement and using minimal fly ash effectively lower the hydration temperature.However,the influence of fly ash on prestress losses should be carefully evaluated during the design phase.Higher initial casting temperatures accelerate hydration rates,leading to a rapid temperature rise.Significant differences between the initial casting and ambient temperatures result in larger residual temperature stresses.Based on concrete mix proportions,curing conditions,and ambient temperatures,three recommended casting temperature ranges were identified:5℃–10℃,10℃–25℃,and 25℃–30℃.Variations in the average ambient temperature affect the peak temperature of the hydration reaction and indirectly influence the final temperature distribution of the concrete structure.Optimizing the demolding time and applying geotextiles and water curing effectively reduces the peak temperature,maximum internal-to-surface temperature gradients,and surface tensile stresses,thereby mitigating the risk of temperature-induced cracking. 展开更多
关键词 Corrugated steel web composite box girder finite element temperature field temperature stress
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Analytical solution of overlying pressure for shallowly buried underwater box tunnel:A case study of box jacking in Suzhou,China
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作者 Cheng Cheng Pengjiao Jia +3 位作者 Pengpeng Ni Peixin Shi Qiao Xiang Yang Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2328-2343,共16页
Accurately predicting the overlying pressure is crucial for determining an appropriate cover depth of underwater box tunnels to avoid the uplifting failure.Based on the project of box jacking crossing the Beijing-Hang... Accurately predicting the overlying pressure is crucial for determining an appropriate cover depth of underwater box tunnels to avoid the uplifting failure.Based on the project of box jacking crossing the Beijing-Hangzhou Grand Canal in Suzhou,the characteristics of overlying pressure variation during tunneling are investigated.The monitoring results reveal that the fluctuation of overlying pressure is weakened during the rapid tunneling process.A modified analytical model for vertical earth pressure is conceived,in which the active and passive limit states for multi-layered soils are both considered.The probable range of overlying pressure obtained by the proposed model is suitable to cover the actual values.The anti-floating behavior of underwater box tunnels for two different working conditions is discussed by calculating the minimum cover depth.Using the calibrated analytical models,a parametric study is conducted to explore the influence of injection pressure,hardened slurry unit weight,soil internal friction angle,soil cohesion,and tunnel geometry.It is found that the injection pressure during the construction process is crucial for determining the necessary cover depth,and the change of box tunnel height makes it easier to trigger the variation of minimum cover depth. 展开更多
关键词 Underwater box tunnel Overlying pressure Minimum cover depth Anti-floating behavior
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Investigation of the clinical significance of the expression of immunohistochemical biomarkers Enhancer of zeste homolog 2 and Forkhead box M1 in localized prostate cancer tissue:A Greek retrospective study
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作者 Sotirios Koubardas Dimitrios Goutas +5 位作者 Iliana Mani Evangelia Krikou Ourania Mpatsi Harikleia Gakiopoulou Christos Alamanis Andreas C.Lazaris 《Asian Journal of Urology》 2025年第3期357-365,共9页
Objective:In recent decades,studies have underscored nuclear proteins and signaling pathways in prostate cancer(PCa)development.Key biomarkers like Enhancer of zeste homolog 2(EZH2)and Forkhead box M1(FOXM1)are expres... Objective:In recent decades,studies have underscored nuclear proteins and signaling pathways in prostate cancer(PCa)development.Key biomarkers like Enhancer of zeste homolog 2(EZH2)and Forkhead box M1(FOXM1)are expressed in both healthy and malignant prostate cells.This study aimed to demonstrate the relationship between pathological characteristics,survival,recurrence,and tissue expression of EZH2 and FOXM1 in high-risk PCa patients.Methods:PCa tissues were used in a retrospective analysis that spanned from September 2009 to August 2019.Inclusion criteria comprised pathological tumor stage(pT)3 patients with positive surgical margins or tumor proximity to inked margins within 5 mm.After case selection,tissue slides were stained for EZH2 and FOXM1 antibodies,and Allred scores were calculated.Patients or relatives of deceased patients were contacted for signed agreements and disease follow-ups.Results:The pT3b,ductal carcinoma component,and moderate EZH2 expression were associated with relapse(odds ratio[OR]6.21,95%confidence interval[CI]1.41-27.27,p=0.016;OR 7.29,95%CI 1.03-51.43,p=0.046;OR 5.96,95%CI 1.09-32.48,p=0.039;respectively).The unilateral and bilateral seminal vesicle invasion increased the likelihood of recurrence by 9.98 times and 5.36 times,and the risk of death by around 9.78 times and 10.79 times,respectively.The pT3b was linked to higher death likelihood(OR 7.16,95%CI 1.38-37.23,p=0.019),while moderate EZH2 expression did not show statistical significance(OR 4.54,95%CI 0.87-23.60,p=0.072,marginally).Pathological regional lymph node stage(pN)1 had significantly higher probability of mortality than pN unknown(3.9%vs.27%,p<0.001).PCa in the neck and apex of the prostate gland increased death risk tenfold.Conclusion:Sufficient immunoexpression of EZH2,ductal carcinoma component,and neoplastic proliferation in the seminal vesicles,apex and neck of the prostate gland correlates with elevated risks of recurrence and mortality.Clinicians should use these criteria for appropriate patient referrals,and a multicenter trial could provide accurate classifications. 展开更多
关键词 Death Enhancer of zeste homolog 2 Forkhead box M1 Prostate cancer Relapse
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An estimating methodology for the load of train axle box bearings
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作者 Zhenqian Li Maoru Chi +1 位作者 Wubin Cai Yabo Zhou 《High-Speed Railway》 2025年第4期267-280,共14页
Axle box bearings serve as crucial components within the transmission system of high-speed trains.Their failure can directly impact the operational safety of these trains.Accurately determining the dynamic load experi... Axle box bearings serve as crucial components within the transmission system of high-speed trains.Their failure can directly impact the operational safety of these trains.Accurately determining the dynamic load experienced by bearings during the operation of high-speed trains can provide valuable boundary inputs for the study of bearing fatigue life and service performance,thereby holding significant engineering implications.In this study,we propose a high-speed train axle box bearing load estimation method(FMCC-DKF).This method is founded on the Kalman filtering technique of the Maximum Correntropy Criterion(MCC)and employs dummy measurement technology to enhance the stability of estimated loads.We develop a kernel size update algorithm to address the challenges associated with obtaining the key parameter,kernel size of MCC.Comparative analysis of the vertical and lateral loads of the axle box bearing obtained using FMCC-DKF,DKF,and AMCC-DKF,under both measurement noise-free and non-Gaussian noise conditions,is conducted to demonstrate the superiority of the proposed estimation method.The results indicate that the proposed FMCC-DKF method exhibits high estimation accuracy under both measurement noise-free and non-Gaussian noise interference,and maintains its high estimation accuracy despite changes in train speed.The proposed load estimation method demonstrates reliable performance within the low-frequency domain below 70 Hz. 展开更多
关键词 Axle box bearing load Load estimation Maximum correntropy criterion Non-Gaussian noise High-speed train
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