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Hydrodynamic Behavior of Gap Resonance in Multiple-Box Systems with Sharp and Round Inlet Configurations 被引量:2
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作者 RAN Ya-qing JIANG Sheng-chao +1 位作者 GENG Bao-lei JIN Rui-jia 《China Ocean Engineering》 SCIE EI CSCD 2023年第5期849-862,共14页
Fluid resonance within narrow gaps in multiple-box systems with sharp and round inlet configurations are investigated by using the potential flow and viscous fluid flow models in the OpenFOAM^(■)package.Evident discr... Fluid resonance within narrow gaps in multiple-box systems with sharp and round inlet configurations are investigated by using the potential flow and viscous fluid flow models in the OpenFOAM^(■)package.Evident discrepancy between two numerical models can be observed for sharp inlet configurations.In addition to the dramatical decrease of resonant amplitude in narrow gaps,some peak values at the higher resonant frequencies predicted by the potential flow model even disappear in the viscous fluid flow results.The decreased normalized resonant amplitudes with the increase of incident wave amplitude can be observed for sharp inlet configurations.However,the hydrodynamic behaviors of multiple-box system with round inlet configurations between potential flow and viscous fluid flow models are quite similar with each other.The normalized resonant amplitudes are nearly independent of incident wave amplitudes for multiple-box systems with round inlet configurations.This implies that the energy dissipation associated with fluid viscosity and flow rotation plays an important role in the gap resonance for sharp inlet configurations;while it is insignificant for round inlet configurations. 展开更多
关键词 fluid resonance multiple boxes sharp edge round edge OpenFOAM
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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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Bearing characteristics of anchor box beam support system in deep thick roof coal roadway and its application
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作者 WANG Qi WANG Ming-zi +1 位作者 JIANG Bei XU Chuan-jie 《Journal of Central South University》 2025年第5期1887-1902,共16页
Considering the characteristics of deep thick top coal roadway,in which the high ground stress,coal seam with low strength,and a large range of surrounding rock fragmentation,the pressure relief anchor box beam suppor... Considering the characteristics of deep thick top coal roadway,in which the high ground stress,coal seam with low strength,and a large range of surrounding rock fragmentation,the pressure relief anchor box beam support system with high strength is developed.The high-strength bearing characteristics and coupling yielding support mechanism of this support system are studied by the mechanical tests of composite members and the combined support system.The test results show that under the coupling effect of support members,the peak stress of the box-shaped support beam in the anchor box beam is reduced by 21.9%,and the average deformation is increased by 135.0%.The ultimate bending bearing capacity of the box-shaped support beam is 3.5 times that of traditional channel beam.The effective compressive stress zone applied by the high prestressed cable is expanded by 26.4%.On this basis,the field support comparison test by the anchor channel beam,the anchor I-shaped beam and the anchor box beam are carried out.Compared with those of the previous two,the surrounding rock convergence of the latter is decreased by 41.2%and 22.2%,respectively.The field test verifies the effectiveness of the anchor box beam support system. 展开更多
关键词 thick roof coal roadway anchor box beam bearing characteristics combined support field application
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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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Expert System for the Design of Single Speed Gear Boxes
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作者 黄心渊 万耀青 +1 位作者 项红 王文清 《Journal of Beijing Institute of Technology》 EI CAS 1992年第1期35-41,共7页
Based on the characteristic peculiarities of mechanical design expert systems (MDES), the design process pf gear box and its components is introduced and the gear box design expert systems (GBES)is established. GBES e... Based on the characteristic peculiarities of mechanical design expert systems (MDES), the design process pf gear box and its components is introduced and the gear box design expert systems (GBES)is established. GBES employs the methods of knowledge representation to indicate the knowledge-unit-rule-process, table-vector-process. By taking the advantage of knowledge unit's indicator, it can make the units of knowledge base to to combine to form a whole in the feature of trees and nets so that it can give deduction conveniently. The knowledge base of GBES is organized in hierarchy, which provides the efficient managerial systems of knowledge base. It makes the knowledge base convenient greatly for establishing and using. The assistant modules of GBES are written in FORTRAN and the part of expert systems is written in LISP. It explains the I/O among each module and the forms of independent application. The GBES systems have been put into preliminary, use in practice. 展开更多
关键词 OPTIMIZATION CAD gear box expert system
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Novel insights for high mobility group box 1 proteinmediated cellular immune response in sepsis:A systemic review 被引量:20
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作者 Li-feng Huang Yong-ming Yao Zhi-yong Sheng 《World Journal of Emergency Medicine》 CAS 2012年第3期165-171,共7页
High mobility group box 1 protein (HMGB1) is a highly conserved, ubiquitous protein in the nuclei and cytoplasm of nearly all cell types. HMGB1 is secreted into the extracellular milieu and acts as a proinflammatory... High mobility group box 1 protein (HMGB1) is a highly conserved, ubiquitous protein in the nuclei and cytoplasm of nearly all cell types. HMGB1 is secreted into the extracellular milieu and acts as a proinflammatory cytokine. In this article we reviewed briefly the cellular immune response mediated by HMGB1 in inflammation and sepsis. This systemic review is mainly based on our own work and other related reports HMGB1 can actively affect the immune functions of many types of cells including T lymphocytes, regulatory T cells (Tregs), dendritic cells (DCs), macrophages, and natural killer cells (NK cells). Various cellular responses can be mediated by HMGB1 which binds to cell-surface receptors [e.g., the receptor for advanced glycation end products (RAGE), Toll-like receptor (TLR)2, and TLR4]. Anti-HMGB1 treatment, such as anti-HMGB1 polyclonal or monoclonal antibodies, inhibitors (e.g., ethyl pyruvate) and antagonists (e.g., A box), can protect against sepsis lethality and give a wider window for the treatment opportunity. HMGB1 is an attractive target for the development of new therapeutic strategies in the treatment of patients with septic complications. 展开更多
关键词 High mobility group box 1 protein SEPSIS Immunological effect CYTOKINE Signal transduction
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Fatigue Performance Analysis and Evaluation for Steel Box Girder Based on Structural Health Monitoring System 被引量:1
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作者 Meiling Zhuang Changqing Miao Rongfeng Chen 《Structural Durability & Health Monitoring》 EI 2020年第1期51-79,共29页
Taizhou Yangtze River Bridge as a long-span suspension bridge,the finite element model(FEM)of it is established using the ANSYS Software.The beam4 element is used to simulate the main beam to establish the“spine beam... Taizhou Yangtze River Bridge as a long-span suspension bridge,the finite element model(FEM)of it is established using the ANSYS Software.The beam4 element is used to simulate the main beam to establish the“spine beam”model of the Taizhou Yangtze River Bridge.The calculated low-order vibration mode frequency of the FEM is in good agreement with the completion test results.The model can simulate the overall dynamic response of the bridge.Based on the vehicle load survey,the Monte Carlo method is applied to simulate the traffic load flow.Then the overall dynamic response analysis of FEM is car-ried out.Taking the bending moment of the main beam as the control index,the fatigue sensitive section in the steel box girder of FEM is analyzed.Based on the strain time history data of steel box girder recorded by the structural health mon-itoring system(SHM),the true stress response of steel box girder under vehicle load is extracted.Taking the cumulative fatigue damage increment as the evalua-tion index,the fati gue performance evaluation of the steel box girders is con-ducted based on the collected health monitoring data.The fatigue effect of the beam section near the steel tower,especially the first section of the middle tower,is the key section of the fatigue analysis by health morning system,which is con-sistent with the calculation results of FEM. 展开更多
关键词 Steel box girder FATIGUE stress response Monte Carlo method structural health monitoring system
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Closed-loop identification of systems using hybrid Box–Jenkins structure and its application to PID tuning 被引量:1
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作者 李全善 李大字 曹柳林 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期1997-2004,共8页
The paper describes a closed-loop system identification procedure for hybrid continuous-time Box–Jenkins models and demonstrates how it can be used for IMC based PID controller tuning. An instrumental variable algori... The paper describes a closed-loop system identification procedure for hybrid continuous-time Box–Jenkins models and demonstrates how it can be used for IMC based PID controller tuning. An instrumental variable algorithm is used to identify hybrid continuous-time transfer function models of the Box–Jenkins form from discretetime prefiltered data, where the process model is a continuous-time transfer function, while the noise is represented as a discrete-time ARMA process. A novel penalized maximum-likelihood approach is used for estimating the discrete-time ARMA process and a circulatory noise elimination identification method is employed to estimate process model. The input–output data of a process are affected by additive circulatory noise in a closedloop. The noise-free input–output data of the process are obtained using the proposed method by removing these circulatory noise components. The process model can be achieved by using instrumental variable estimation method with prefiltered noise-free input–output data. The performance of the proposed hybrid parameter estimation scheme is evaluated by the Monte Carlo simulation analysis. Simulation results illustrate the efficacy of the proposed procedure. The methodology has been successfully applied in tuning of IMC based flow controller and a practical application demonstrates the applicability of the algorithm. 展开更多
关键词 Hybrid box–Jenkins models ARMA models Instrumental variable Closed-loop identification PID tuning
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Boxing Practitioners Physiology Review: 2. Systemic Responses and Adaptations
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作者 André Mukala Nsengu Tshibangu 《Open Journal of Molecular and Integrative Physiology》 CAS 2023年第1期1-67,共67页
The present journal paper is the second of the three parts of a whole boxing practitioners physiology review. It is related to the boxing practice-derived systemic responses and adaptations. The first part of the revi... The present journal paper is the second of the three parts of a whole boxing practitioners physiology review. It is related to the boxing practice-derived systemic responses and adaptations. The first part of the review has dealt with kinanthropometric parameters, skeletal muscle recruitment and ergometry. The following and third part of the review is going to deal with dietary supplementation, weight control, recovery, altitude, faith, life expectancy, gender and childhood. Search engines and printed documents have helped gather the information that have been commented in the present and second part: responses and/or adaptations relating to 1) metabolism, 2) skeleton, 3) nervous system, 4) endocrine system, 5) cardiovascular system, 6) urinary tract and 7) pulmonary system. Detailed titles and subtitles of this part of the review are found at the end of the journal paper introduction. The main teachings from the present journal paper may be acquired through the consultation of the tables and figures that are positioned in the text, not forgetting the reminders and advice(s) that appear at the end of each of the seven parts of the journal paper (2.1.6., 2.2.2., 2.3.2., 2.4.2., 2.5.4, 2.6.4. and 2.7.3.). 展开更多
关键词 boxING Integrative Physiology Martial Arts Molecular Physiology Musculoskeletal Physiology
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Gearbox Scheme in High Temperature Reactor Helium Gas Turbine System
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作者 Sheng Liu Xuanyu Sheng 《World Journal of Nuclear Science and Technology》 2012年第3期85-88,共4页
Helium Turbine is used in High Temperature Reactor Helium Gas Turbine (HTR-GT) system, by which the direct helium circulation between the reactor and turbine generator system will come true. Between helium turbine and... Helium Turbine is used in High Temperature Reactor Helium Gas Turbine (HTR-GT) system, by which the direct helium circulation between the reactor and turbine generator system will come true. Between helium turbine and generator, there is gearbox device which reduces the turbine rotation speed to normal speed required by the generator. Three optional gearbox schemes are discussed. The first is single reduction cylindrical gearbox, which consists of one high speed gear and one low speed gear. Its advantage is simple structure, easy to manufacture, and high reliability, while its disadvantage is large volume and misalignment of input and output axle. The second is planetary gear mechanism with static planet carrier. The third is planetary gear mechanism with static internal gear. The latter two gearbox devices have similar structure. Their advantage is small volume and high reduction gear ratio, while disadvantage are complicated structure, many gears, low reliability and low mechanical efficiency. 展开更多
关键词 High Temperature Gas Cooled REACTOR GEAR box PLANETARY GEAR
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Temperature Field of PC Box Girder Bridge Based on GPRS Temperature Collection System
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作者 YANG Zeying LIU Jing +2 位作者 QU Jianbo ZHOU Xiangshan LI Lixin 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第3期269-276,共8页
In order to study the temperature distribution and the corresponding temperature effects on pre-stressed concrete(PC) curved box girder bridge in Shandong Province, this paper builds and adopts an automatic remote r... In order to study the temperature distribution and the corresponding temperature effects on pre-stressed concrete(PC) curved box girder bridge in Shandong Province, this paper builds and adopts an automatic remote real-time temperature collection system to collect temperature data on site, and further uses the software ANSYS for analysis. Based on the comparisons between the measured data and the simulation results, the following conclusions can be drawn: 1 Our temperature monitoring system is reliable; 2 The corresponding measured data of the web plate and flange plate exposed to the sun, vary more severely than that at other positions, so these plates need higher standard design and construction requirements; 3 In the cold wave where still is sunshine, the box girder temperature effect behaves as sine-like curve. 展开更多
关键词 bridge engineering concrete curved box girder bridge temperature distribution and temperature effect measured data and finite element analysis
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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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On the Effectiveness of the System Validation Based on the Black Box Testing Methodology
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作者 Dusica Marijan Nikola Teslic +1 位作者 Miodrag Temerinac Vukota Pekovic 《Journal of Electronic Science and Technology of China》 2009年第4期385-389,共5页
With the advancement of technology in recent years, effective fault diagnosis became a necessity to verify the performance and ensure the quality of complex systems. In this paper, an original verification methodology... With the advancement of technology in recent years, effective fault diagnosis became a necessity to verify the performance and ensure the quality of complex systems. In this paper, an original verification methodology for complex consumer electronic devices is presented. Verification of the system which consists of hardware (integrated circuit) and corresponding software within a flat panel TV set is in the focus. Proposed methodology provides reliable functional failure detection using the concept of black box testing. Further, the approach is fully automated, improving the reliability and speed of failure detection. The methodology effectiveness has been experimentally evaluated and the analysis results have been reported. 展开更多
关键词 Automated verification black box testiug system failure detection system fault diagnosis.
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Design of strong S-boxes based on spatiotemporal chaotic system
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作者 徐刚 赵耿 闵乐泉 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第6期107-112,共6页
A substitution box (S-box) plays an important role in cryptographic algorithms.The design of S-box using chaotic systems has attracted a great deal of attention in recent years.A new method for obtaining cryptographic... A substitution box (S-box) plays an important role in cryptographic algorithms.The design of S-box using chaotic systems has attracted a great deal of attention in recent years.A new method for obtaining cryptographically strong S-boxes based on spatiotemporal chaotic system is proposed in this paper.The discretized Baker map and affine transformation are used orderly by an algorithm to shuffle the table generated by the spatiotemporal chaotic system.The cryptographical properties of these S-boxes such as bijection,nonlinearity,strict avalanche,output bits independence and equiprobable input /output XOR distribution are analyzed.The results of numerical analysis show that the S-box designed by this method can against several attacks and all the criteria for designing good S-box can be satisfied approximately.More strong S-boxes can be obtained by this method with the change of the original conditions or control parameters of the spatiotemporal chaos system.Furthermore,our approach is suitable for practical application in designing cryptosystem. 展开更多
关键词 spatiotemporal chaotic system S-box CRYPTANALYSIS
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Functions of nuclear factor Y in nervous system development,function and health
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作者 Pedro Moreira Roger Pocock 《Neural Regeneration Research》 SCIE CAS 2025年第10期2887-2894,共8页
Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 y... Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 years,research has revealed that the nuclear factor Y complex controls many aspects of brain development,including differentiation,axon guidance,homeostasis,disease,and most recently regeneration.However,a complete understanding of transcriptional regulatory networks,including how the nuclear factor Y complex binds to specific CCAAT boxes to perform its function remains elusive.In this review,we explore the nuclear factor Y complex’s role and mode of action during brain development,as well as how genomic technologies may expand understanding of this key regulator of gene expression. 展开更多
关键词 axon guidance CCAAT boxes neuronal degeneration neuronal differentiation neuronal regeneration nuclear factor Y complex transcription factor transcriptional regulation
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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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Cable Vector Collision Detection Algorithm for Multi-Robot Collaborative Towing System
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作者 Ll Tao ZHAO Zhigang +1 位作者 ZHU Mingtong ZHAO Xiangtang 《Journal of Shanghai Jiaotong university(Science)》 2025年第2期319-329,共11页
For the process of multi-robot collaboration to lift the same lifted object by flexible cables,the existing collision detection algorithm of cables between the environmental obstacles has the problem of misjudgment an... For the process of multi-robot collaboration to lift the same lifted object by flexible cables,the existing collision detection algorithm of cables between the environmental obstacles has the problem of misjudgment and omission.In this work,the collision detection of cable vector was studied,and the purpose of collision detection was realized by algorithm.Considering the characteristics of cables themselves,based on oriented bounding box theory,the cable optimization model and environmental obstacle model were established,and a new basic geometric collision detection model was proposed.Then a fast cable vector collision detection algorithm and an optimization principle were proposed.Finally,the rationality of the cable collision detection model and the effectiveness of the proposed algorithm were verified by simulation.Simulation results show that the proposed method can meet the requirements of the fast detection and the accuracy in complex virtual environment.The results lay a foundation for obstacle avoidance motion planning of system. 展开更多
关键词 multi-robot system bounding box CABLE-DRIVEN collision detection
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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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