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Accumulative-Error-Based Event-Triggered Control for Discrete-Time Linear Systems:A Discrete-Time Looped Functional Method 被引量:1
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作者 Xian-Ming Zhang Qing-Long Han +1 位作者 Xiaohua Ge Bao-Lin Zhang 《IEEE/CAA Journal of Automatica Sinica》 2025年第4期683-693,共11页
This paper is concerned with event-triggered control of discrete-time systems with or without input saturation.First,an accumulative-error-based event-triggered scheme is devised for control updates.When the accumulat... This paper is concerned with event-triggered control of discrete-time systems with or without input saturation.First,an accumulative-error-based event-triggered scheme is devised for control updates.When the accumulated error between the current state and the latest control update exceeds a certain threshold,an event is triggered.Such a scheme can ensure the event-generator works at a relatively low rate rather than falls into hibernation especially after the system steps into its steady state.Second,the looped functional method for continuous-time systems is extended to discrete-time systems.By introducing an innovative looped functional that links the event-triggered scheme,some sufficient conditions for the co-design of control gain and event-triggered parameters are obtained in terms of linear matrix inequalities with a couple of tuning parameters.Then,the proposed method is applied to discrete-time systems with input saturation.As a result,both suitable control gains and event-triggered parameters are also co-designed to ensure the system trajectories converge to the region of attraction.Finally,an unstable reactor system and an inverted pendulum system are given to show the effectiveness of the proposed method. 展开更多
关键词 Discrete-time linear systems event-triggered control input saturation looped functional method
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The Looped Light of the Triple-Slit Real Experiment as a Confirmation for the Extra Dimensions of Quantum Spacetime and the Reality of Dark Energy 被引量:1
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作者 Mohamed S. El Naschie 《Optics and Photonics Journal》 2017年第2期19-26,共8页
Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence... Looped light in a recent sophisticated real three-slit experiment is interpreted as a strong justification of the old theoretical Peano-Hilbert spacetime model of Ord and El Naschie. This in turn entails the existence of extra fractal dimensions and consequently of real dark energy density in full agreement with previous analysis as well as accurate measurements and observations of COBE, WMAP, and the type 1a supernova. 展开更多
关键词 looped LIGHT Dark Energy E-INFINITY Cantorian SPACETIME Peano-Hilbert SPACETIME Model Triple-Slit EXPERIMENT Fractal Kaluza-Klein Theory WMAP Type La Supernova
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An Augmented Jacobian Method for Power Flow Analysis of Weakly Looped Distribution Systems with PV Buses
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作者 陈星莺 余昆 单渊达 《Journal of Southeast University(English Edition)》 EI CAS 2002年第3期216-220,共5页
A power flow analysis method for weakly looped distribution systems with PV buses is proposed in this paper. The proposed method is computationally more efficient and more robust compared with the conventional compens... A power flow analysis method for weakly looped distribution systems with PV buses is proposed in this paper. The proposed method is computationally more efficient and more robust compared with the conventional compensation methods. The robustness is achieved by embedding the boundary conditions of loops and PV buses into the Jacobian matrix. The computational efficiency is achieved by the carefully designed factorization of Jacobian matrix. Test results on a 33 bus system are presented. 展开更多
关键词 power flow radial distribution systems weakly loops PV bus
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Looped,Broad,and Deep Buried Suturing Technique for Wound Closure 被引量:3
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作者 Xuwen TANG Yong ZHANG +1 位作者 Liu YANG Dongyun YANG 《Chinese Journal of Plastic and Reconstructive Surgery》 2021年第2期85-88,共4页
This study explores the clinical application of the circular wide and deep(looped,broad,and deep buried,LBD)suture technique for scar resection and examines its clinical effectiveness for scar treatment.From June 2017... This study explores the clinical application of the circular wide and deep(looped,broad,and deep buried,LBD)suture technique for scar resection and examines its clinical effectiveness for scar treatment.From June 2017 to March 2019,a total of 68 patients with scars were sutured using LBD technique,and recovery was achieved 24 months postoperatively.In all 68 patients,postoperative scars were slightly evident in two cases of cervical scar,one case of leg scar,and one case of chest scar.In addition,the remaining 62 patients were completely satisfied with the outcome.The LBD suturing technique could provide sustained and stable tension-reducing effects postoperatively and significantly improve scar formation in patients.This method is most applicable to incisions with tension.Therefore,it should be more widely used for clinical scar treatment. 展开更多
关键词 Suture technology looped broad and deep buried suturing technique Scar resection Cosmetic technology
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Simultaneous production and utilization of methanol for methyl formate synthesis in a looped heat exchanger reactor configuration
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作者 A.Goosheneshin R.Maleki +2 位作者 D.Iranshahi M.R.Rahimpour A.Jahanmiri 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第6期661-672,共12页
In this investigation, a novel thermally coupled reactor (TCR) containing methyl formate (MF) production in the endothermic side and methanol synthesis in the exothermic side has been investigated. The interesting... In this investigation, a novel thermally coupled reactor (TCR) containing methyl formate (MF) production in the endothermic side and methanol synthesis in the exothermic side has been investigated. The interesting feature of this TCR is that productive methanol in the exothermic side could be recycled and used as feed of endothermic side for MF synthesis. Other important advantages of the proposed system are high production rates of hydrogen and MF. The configuration consists of two thermally coupled concentric tubular reactors. In these coupled reactors, autothermal system is obtained within the reactor. A steady-state heterogeneous model is used for simulation of the coupled reactor. The proposed model has been utilized to compare the performance of TCR with the conventional methanol reactor (CMR). Noticeable enhancement can be obtained in the performance of the reactors. The influence of operational parameters is studied on reactor performance. The results show that coupling of these reactions could be feasible and beneficial. Experimental proof-of-concept is required to validate the operation of the novel reactor. 展开更多
关键词 methyl formate methanol synthesis looped heat exchanger reactor configuration steady-state heterogeneous model
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Looped Light on Dark Energy
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作者 Mohamed S. El Naschie 《Journal of Quantum Information Science》 2017年第2期43-47,共5页
We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of q... We give a mathematical golden mean distribution based probabilistic confirmation of a recent spectacular experiment with light. The experiment in question is a three-slit variant of the well known two-slit set up of quantum mechanics. The outcome of the sophisticated experiment revealed the looped path of light on the quantum scale and consequently the Peano-Hilbert geometry of spacetime, ergo its fractal-Cantorian nature. The mathematics used here on the other hand is the remarkably simple and insightful golden mean probability distribution known from a famous paradox known in social sciences as the voter paradox. 展开更多
关键词 Dark Energy the VOTER PARADOX Golden Mean Distribution looped LIGHT the Triple-Slit Experiment Cantorian-Fractal SPACETIME
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碳足迹领域人工智能应用的监管与挑战
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作者 华潮 陆文静 苗建军 《信息记录材料》 2026年第2期16-18,共3页
为应对人工智能(AI)在碳足迹领域应用中的风险防控与监管挑战,本文引入SETO Loop(scope⁃existing regulation⁃tool⁃organization)模型构建AI监管分析框架,探讨AI赋能的碳足迹检测、预测与控制如何重塑农业、工业领域产业集聚与碳排放监... 为应对人工智能(AI)在碳足迹领域应用中的风险防控与监管挑战,本文引入SETO Loop(scope⁃existing regulation⁃tool⁃organization)模型构建AI监管分析框架,探讨AI赋能的碳足迹检测、预测与控制如何重塑农业、工业领域产业集聚与碳排放监管关联机制。通过SETO Loop框架的系统分析,AI碳足迹应用的监管需聚焦以下维度:界定保护范围(涵盖人类、个人、国家及市场)、分析现有法规、协调组织设计及选择多元化监管工具。该框架为平衡动态技术创新与风险防控提供了系统性路径,以应对AI碳足迹监管的复杂性。 展开更多
关键词 SETO Loop 人工智能(AI) 碳足迹 监管工具
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Dynamic modeling and analysis of the looped space tether transportation system based on ANCF 被引量:1
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作者 Jie Yang Qingtao Wang +3 位作者 Zhiyong Zhang Zhendong Liu Shidong Xu Gangqiang Li 《International Journal of Mechanical System Dynamics》 2022年第2期204-213,共10页
A high‐fidelity multibody‐system dynamic model of the looped tether transportation system(L‐TTS)is proposed in this study to study its large deformation as well as large overall motion.The absolute nodal coordinate... A high‐fidelity multibody‐system dynamic model of the looped tether transportation system(L‐TTS)is proposed in this study to study its large deformation as well as large overall motion.The absolute nodal coordinate formulation(ANCF)‐based gradient‐deficient beam element is employed to establish the accurate model of the two flexible tethers subject to large deformations.The relative movement of climbers along tethers is described by using the sliding joint model based on ANCF.To reduce the collision risks between tethers and climbers,two libration suppression strategies,namely,the decelerated motion of climbers relative to tethers and multiple climbers per tether are investigated in this study.Several numerical simulations not only validate the effectiveness of the two strategies in reducing the collision risks between climbers and tethers,the overall librations of L‐TTS,and the magnitudes of the longitudinal elastic force of tethers,but also verify the good performance of the high‐fidelity model proposed in this study for dynamic simulation of the L‐TTS in microgravity conditions. 展开更多
关键词 looped tether transportation system high‐fidelity model absolute nodal coordinate formulation sliding joints libration suppression
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Design and experimental validation of looped-tube thermoacoustic engine
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作者 Abdulrahman S. Abduljalil Zhibin Yu Artur J. Jaworski 《Journal of Thermal Science》 SCIE EI CAS CSCD 2011年第5期423-429,共7页
The aim of this paper is to present the design and experimental validation process for a thermoacoustic looped-tube engine. The design procedure consists of numerical modelling of the system using DELTA EC tool, Desig... The aim of this paper is to present the design and experimental validation process for a thermoacoustic looped-tube engine. The design procedure consists of numerical modelling of the system using DELTA EC tool, Design Environment for Low-amplitude ThermoAcousfic Energy Conversion, in particular the effects of mean pressure and regenerator configuration on the pressure amplitude and acoustic power generated. This is followed by the construction of a practical engine system equipped with a ceramic regenerator - a substrate used in auto- motive catalytic converters with fine square channels. The preliminary testing results are obtained and compared with the simulations in detail.The measurement results agree very well on the qualitative level and are reasonably close in the quantitative sense. 展开更多
关键词 Thermoacoustic engine looped tube MODELLING SIMULATION
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Pathogenic analysis of post-transplantation obesity:A comprehensive systematic review
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作者 Ke-Ran Chen Lin-Zhi Wu +4 位作者 Yi-Ning Huang Si-Yu Zhuang Ze-Yu Chen Bin Xu Tian-Cheng Xu 《World Journal of Transplantation》 2026年第1期213-222,共10页
BACKGROUND Organ transplantation has emerged as a globally prevalent therapeutic modality for end-stage organ failure,yet the post-transplantation trajectory is increasingly complicated by a spectrum of metabolic sequ... BACKGROUND Organ transplantation has emerged as a globally prevalent therapeutic modality for end-stage organ failure,yet the post-transplantation trajectory is increasingly complicated by a spectrum of metabolic sequelae,with obesity emerging as a critical clinical challenge.AIM To systematically review the multifactorial mechanisms underlying obesity following organ transplantation and to integrate evidence from pharmacological,behavioral,and molecular perspectives,thereby providing a foundation for targeted interventions.METHODS We conducted a systematic search in PubMed and Web of Science for literature published from 2020 to 15 July 2025.The search strategy incorporated terms including“obesity”,“overweight”and“post organ transplantation”.Only randomized controlled trials,meta-analyses,and systematic reviews were included.Non-empirical publications and irrelevant studies were excluded.Data extraction and quality assessment were performed by two independent reviewers,with disagreements resolved by a third researcher.RESULTS A total of 1457 articles were initially identified,of which 146 met the inclusion criteria.These studies encompassed liver,kidney,heart,and lung transplant recipients.Key findings indicate that immunosuppressive drugs-especially corticosteroids and calcineurin inhibitors-promote hyperphagia,insulin resistance,and dyslipidemia.Post-transplant sedentary behavior and hypercaloric diets further contribute to positive energy balance.At the molecular level,immunosuppressants disrupt adipokine signaling(e.g.,leptin and adiponectin),induce inflammatory and oxidative stress responses,and activate adipogenic pathways leading to lipid accumulation.CONCLUSION Post-transplant obesity arises from a complex interplay of pharmacological,behavioral,and molecular factors.A multidisciplinary approach-incorporating pharmacological modification,nutritional management,physical activity,and molecular-targeted therapies-is essential to mitigate obesity and improve transplant outcomes.Further large-scale and mechanistic studies are warranted to establish evidence-based preventive and treatment strategies. 展开更多
关键词 Organ transplantation OBESITY Metabolic dysregulation IMMUNOPHARMACOLOGY Adipokine dysregulation axis Inflammation-oxidation-adipogenesis loop
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Exact Computer Modeling of Photovoltaic Sources with Lambert-W Explicit Solvers for Real-Time Emulation and Controller Verification
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作者 Abdulaziz Almalaq Ambe Harrison +2 位作者 Ibrahim Alsaleh Abdullah Alassaf Mashari Alangari 《Computer Modeling in Engineering & Sciences》 2026年第1期873-891,共19页
We present a computer-modeling framework for photovoltaic(PV)source emulation that preserves the exact single-diode physics while enabling iteration-free,real-time evaluation.We derive two closed-form explicit solvers... We present a computer-modeling framework for photovoltaic(PV)source emulation that preserves the exact single-diode physics while enabling iteration-free,real-time evaluation.We derive two closed-form explicit solvers based on the Lambert W function:a voltage-driven V-Lambert solver for high-fidelity I–V computation and a resistance-driven R-Lambert solver designed for seamless integration in a closed-loop PV emulator.Unlike Taylor-linearized explicit models,our proposed formulation retains the exponential nonlinearity of the PV equations.It employs a numerically stable analytical evaluation that eliminates the need for lookup tables and root-finding,all while maintaining limited computational costs and a small memory footprint.The R-Lambert model is integrated into a buck-converter emulator equipped with a discrete PI regulator,which generates current references directly from sensed operating points,thus supporting hardware-constrained implementation.Comprehensive numerical experiments conducted on six commercial modules from various technologies(mono,poly,and multicrystalline)demonstrate significant accuracy improvements under the IEC EN 50530 near-MPP criterion:the V-Lambert solver reduces the±10%Vmpp band error by up to 61 times compared to an explicit-model baseline.Dynamic simulations under varying irradiance,temperature,and load conditions achieve millisecond-scale settling with accurate trajectory tracking.Additionally,processor-in-the-loop experimental validation on an embedded microcontroller supports the simulation results.By unifying exact analytical modeling with embedded realization,this work advances computer modeling for PV emulation,MPPT benchmarking,and controller verification in integrated renewable energy systems. 展开更多
关键词 Photovoltaic emulators(PVE) explicit PV model(EPVM) IEC EN 50530 Lambert function maximum power point(MPP) PVE integration processor-in-the loop
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双向双LOOP技术在超时间窗Aegisy下腔静脉滤器回收中的应用
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作者 叶成 朱小旭 +4 位作者 王贾楠 齐县伟 辛颖 邢程 张宪亮 《介入放射学杂志》 北大核心 2025年第10期1113-1116,共4页
目的总结双向双LOOP技术在腔静脉滤器回收中的应用。方法纳入2016年1月至2023年11月在周口市中心医院住院期间因下肢深静脉血栓形成合并肺栓塞、下肢深静脉血栓形成、行抽栓术下腔静脉滤器置入患者12例。应用标准方法、导丝剥离、球囊... 目的总结双向双LOOP技术在腔静脉滤器回收中的应用。方法纳入2016年1月至2023年11月在周口市中心医院住院期间因下肢深静脉血栓形成合并肺栓塞、下肢深静脉血栓形成、行抽栓术下腔静脉滤器置入患者12例。应用标准方法、导丝剥离、球囊扩张、单向单LOOP和单向双LOOP技术等方法回收超时间窗Aegisy下腔静脉滤器,因回收困难转为使用双向双LOOP技术。滤器留置30~365 d,平均105 d。结果11例患者的滤器被完整取出,造影显示下腔静脉通畅,未见对比剂外溢,平均手术时间126 min。1例患者滤器未被取出,终身抗凝。未发生手术相关并发症。结论双向双LOOP技术安全、有效,值得推广应用。 展开更多
关键词 Aegisy下腔静脉滤器 双向双LOOP
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冷冻电镜结构揭示RNA修饰对核糖体组装和翻译的影响
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作者 张云阳 高宁 《电子显微学报》 北大核心 2025年第1期115-123,共9页
RNA修饰广泛存在于所有主要RNA类别(包括信使RNA、转运RNA和核糖体RNA)中,核糖体RNA(ribosomal RNA,rRNA)因其刚性的结构,为使用冷冻电镜(Cryogenic electron microscopy,Cryo-EM)技术探讨RNA修饰的结构与功能之间的关系提供了一个理想... RNA修饰广泛存在于所有主要RNA类别(包括信使RNA、转运RNA和核糖体RNA)中,核糖体RNA(ribosomal RNA,rRNA)因其刚性的结构,为使用冷冻电镜(Cryogenic electron microscopy,Cryo-EM)技术探讨RNA修饰的结构与功能之间的关系提供了一个理想的平台。rRNA的修饰主要包括甲基化修饰和假尿嘧啶化修饰,这些修饰不仅扩展了rRNA的化学和拓扑属性,还显著影响核糖体亚基的组装和翻译的效率。特别是在肽基转移酶中心(Peptidyl transferase center,PTC)的A-loop区域,rRNA修饰通过影响转运RNA(transfer RNA,tRNA)的选择和肽链的延伸,显著提高蛋白质合成效率。冷冻电镜结构分析在揭示RNA修饰对核糖体组装和翻译的影响方面发挥了重要作用。本综述基于生物化学数据和冷冻电镜结构,详细探讨了rRNA修饰的生物学重要性,并特别强调了A-loop在PTC中的功能和其修饰对核糖体性能的影响。研究表明,A-loop的修饰在原核细胞、真核细胞中显示出高度的保守性,这反映了其在确保蛋白质正确延伸中的关键作用。rRNA的修饰主要由小核仁RNA(small nucleolar RNA,snoRNA)介导,但也包括由独立的甲基转移酶(如RrmJ/Spb1家族)执行的2′-O-甲基化,RrmJ/Spb1家族蛋白识别组装中的核糖体并对A-loop进行修饰,成为核糖体组装过程中关键的质量控制检查点,本综述还分析了RrmJ/Spb1功能缺失或者突变对核糖体组装产生的严重影响。 展开更多
关键词 冷冻电镜 rRNA修饰 rRNA甲基化 肽基转移酶中心(PTC) A⁃loop 核糖体组装 翻译效率
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应用塘鹅嘴型异物钳联合Loop技术完成复杂性滤器回收1例
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作者 吴芳芳 樊炜静 +2 位作者 杨晓 王宏飞 柳国斌 《血管与腔内血管外科杂志》 2025年第4期573-576,共4页
下腔静脉滤器作为预防致死性肺栓塞的关键措施,其植入后并发症与回收困难已成为血管外科的重要挑战。研究表明,下腔静脉滤器早期并发症(如静脉损伤、滤器偏移)发生率约为1.8%,晚期并发症(如滤器移位、穿孔及血栓形成)发生率约为3.1%,均... 下腔静脉滤器作为预防致死性肺栓塞的关键措施,其植入后并发症与回收困难已成为血管外科的重要挑战。研究表明,下腔静脉滤器早期并发症(如静脉损伤、滤器偏移)发生率约为1.8%,晚期并发症(如滤器移位、穿孔及血栓形成)发生率约为3.1%,均显著影响患者的预后情况,其中,女性患者更易出现早期并发症[1-2]。术前评估与精细操作可以降低早期风险,但滤器长期留置导致的组织嵌合或结构异常仍是晚期并发症及回收失败的主要原因。 展开更多
关键词 下腔静脉滤器 塘鹅嘴型异物钳联合Loop技术 深静脉血栓形成
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PLL Frequency Stability Enhancement under Weak Grid Considering Reactive Current Support 被引量:1
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作者 Bin Hu Ling Zhan +1 位作者 Heng Nian Donglian Qi 《CES Transactions on Electrical Machines and Systems》 2025年第1期110-114,共5页
The phase-locked loop(PLL)plays an essential role for synchronizing renewable power generation to the grid.However,as per the grid-code compliance for reactive current support,the PLL output frequency fluctuates signi... The phase-locked loop(PLL)plays an essential role for synchronizing renewable power generation to the grid.However,as per the grid-code compliance for reactive current support,the PLL output frequency fluctuates significantly and exceeds the limitation,which seriously threaten the safe supply of electricity.In this paper,the underlying theoretical mechanism and dominant force behind the maximum PLL frequency deviation are revealed.Accordingly,two feasible approaches are proposed to enhance the PLL frequency stability with validations in experimental results. 展开更多
关键词 Phase-locked loop Renewable power generation Weak grid Reactive current support
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Tm4sf19 inhibition ameliorates inflammation and bone destruction in collagen-induced arthritis by suppressing TLR4-mediated inflammatory signaling and abnormal osteoclast activation 被引量:1
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作者 Sujin Park Kwiyeom Yoon +19 位作者 Eunji Hong Min Woo Kim Min Gi Kang Seiya Mizuno Hye Jin Kim Min-Jung Lee Hee Jae Choi Jin Sun Heo Jin Beom Bae Haein An Naim Park Hyeyeon Park Pyunggang Kim Minjung Son Kyoungwha Pang Je Yeun Park Satoru Takahashi Yong Jung Kwon Dong-Woo Kang Seong-Jin Kim 《Bone Research》 2025年第3期747-759,共13页
Rheumatoid arthritis(RA)is an autoimmune disease characterized by inflammation and abnormal osteoclast activation,leading to bone destruction.We previously demonstrated that the large extracellular loop(LEL)of Tm4sf19... Rheumatoid arthritis(RA)is an autoimmune disease characterized by inflammation and abnormal osteoclast activation,leading to bone destruction.We previously demonstrated that the large extracellular loop(LEL)of Tm4sf19 is important for its function in osteoclast differentiation,and LEL-Fc,a competitive inhibitor of Tm4sf19,effectively suppresses osteoclast multinucleation and prevent bone loss associated with osteoporosis.This study aimed to investigate the role of Tm4sf19 in RA,an inflammatory and abnormal osteoclast disease,using a mouse model of collagen-induced arthritis(CIA).Tm4sf19 expression was observed in macrophages and osteoclasts within the inflamed synovium,and Tm4sf19 expression was increased together with inflammatory genes in the joint bones of CIA-induced mice compared with the sham control group.Inhibition of Tm4sf19 by LEL-Fc demonstrated both preventive and therapeutic effects in a CIA mouse model,reducing the CIA score,swelling,inflammation,cartilage damage,and bone damage.Knockout of Tm4sf19 gene or inhibition of Tm4sf19 activity by LEL-Fc suppressed LPS/IFN-γ-induced TLR4-mediated inflammatory signaling in macrophages.LEL-Fc disrupted not only the interaction between Tm4sf19 and TLR4/MD2,but also the interaction between TLR4 and MD2.μCT analysis showed that LEL-Fc treatment significantly reduced joint bone destruction and bone loss caused by hyperactivated osteoclasts in CIA mice.Taken together,these findings suggest that LELFc may be a potential treatment for RA and RA-induced osteoporosis by simultaneously targeting joint inflammation and bone destruction caused by abnormal osteoclast activation. 展开更多
关键词 TLR osteoclast activation rheumatoid arthritis ra INFLAMMATION collagen induced arthritis rheumatoid arthritis autoimmune disease large extracellular loop lel
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Screening dual variable-valence metal oxides doped calcium-based material for calcium looping thermochemical energy storage and CO_(2)capture with DFT calculation 被引量:1
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作者 Youhao Zhang Yi Fang +4 位作者 Zhiwei Chu Zirui He Jianli Zhao Kuihua Han Yingjie Li 《Journal of Energy Chemistry》 2025年第8期170-182,共13页
The reaction characteristics of calcium-based materials during calcium looping(CaL)process are pivotal in the efficiency of CaL thermochemical energy storage(TCES)and CO_(2)capture systems.Currently,metal oxide doping... The reaction characteristics of calcium-based materials during calcium looping(CaL)process are pivotal in the efficiency of CaL thermochemical energy storage(TCES)and CO_(2)capture systems.Currently,metal oxide doping is the primary method to enhance the reaction characteristics of calcium-based materials over multiple cycles.In particular,co-doping with variable-valence metal oxides(VVMOs)can effectively increase the oxygen vacancy content in calcium-based materials,significantly improving their cyclic reaction characteristics.However,there are so numerous VVMOs co-doping schemes that the experimental screening process is complex,consuming considerable time and economic costs.Density functional theory(DFT)calculations have been widely used to reveal the impact of metal oxide doping on the cyclic reaction characteristics of calcium-based materials,with calculation results showing good agreement with experimental conclusions.Nevertheless,there is still a lack of research on utilizing DFT to screen calcium-based materials,and a systematic research methodology has not yet been established.In this study,a systematic DFT-based screening methodology for calcium-based materials was proposed.A series of key parameters for DFT calculations including CO_(2)adsorption energy,oxygen vacancy formation energy,and sintering resistance were proposed.Furthermore,a preliminary mathematical model to predict the CaL TCES and CO_(2)capture performance of calcium-based materials was introduced.The aforementioned DFT method was employed to screen for VVMOs co-doped calcium-based materials.The results revealed that Mn and Ce co-doped calcium-based materials exhibited superior DFT-predicted reaction characteristics.These DFT predictions were validated through experimental assessments of cyclic thermochemical energy storage,CO_(2)capture,and relevant characterization.The outcomes demonstrate a high degree of consistency among DFT-based predictions,experimental results,and characterization.Hence,the DFT-based screening methodology for calcium-based materials proposed herein is a viable solution,poised to offer theoretical insights for the efficient design of calcium-based materials. 展开更多
关键词 Density functional theorу Calcium looping Material screening Variable-valence metal oxide CO_(2)capture Thermochemical energy storage
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CO_(2)Capture and In Situ Conversion Technologies:Prospects and Perspectives for Green and Low-Energy Transformation 被引量:1
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作者 Xiaochen Han Xiaohui Wang +3 位作者 Xintao Li Mingyu Gao Qian Wang Junting Feng 《Carbon and Hydrogen》 2025年第2期142-163,共22页
CO_(2)capture and utilization(CCU)are two important processes to address the gigaton challenges in reducing greenhouse gas emissions.Given that both processes are energy-intensive,integrating CO_(2)capture and utiliza... CO_(2)capture and utilization(CCU)are two important processes to address the gigaton challenges in reducing greenhouse gas emissions.Given that both processes are energy-intensive,integrating CO_(2)capture and utilization(ICCU)can improve energy efficiency and reduce economic costs by eliminating steps such as CO_(2)concentration,storage,or capture media regeneration.Aiming at building a bridge between theoretical research and practical application,this review promotes the understanding of high-temperature ICCU,mild/low-temperature ICCU,and emerging electro-/photo-driven ICCU.The reaction mechanism and technical bottleneck are comprehensively evaluated,which could provide a perspective on the design principle of dualfunctional materials(DFMs)combining synergetic adsorptive and catalytic sites.On this basis,novel strategies are proposed from the viewpoint of chemical process intensification to strive for a thermodynamics and kinetics matching between the capture and in situ conversion processes.It is expected that this review can stimulate more research in the future involving expanding the product range,fabricating long-term DFMs,developing a workable reactor,optimizing operation conditions,and establishing an industrial demonstration. 展开更多
关键词 carbon neutrality chemical looping dual-function materials(DFMs) electro/photocatalysis integrated CO_(2)capture and utilization(ICCU)
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光学观测数据约束的小行星三维形貌拟真建模方法
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作者 李丰睿 王楷铎 李明涛 《宇航学报》 北大核心 2025年第11期2394-2405,共12页
小行星三维形貌对其探测、防御及资源利用具有关键影响。现有建模方法,如地基光学数据反演形状、探测器成像或随机地形模拟,均难以兼顾精度、效率与成本。为满足多样化的小行星形貌样本验证需求并提升建模真实性与高效性,提出结合地基... 小行星三维形貌对其探测、防御及资源利用具有关键影响。现有建模方法,如地基光学数据反演形状、探测器成像或随机地形模拟,均难以兼顾精度、效率与成本。为满足多样化的小行星形貌样本验证需求并提升建模真实性与高效性,提出结合地基光学观测数据反演与拟真地形模拟的建模方法。首先,通过光学数据反演生成凸面体形状;然后,利用Loop网格细分算法平滑网格,结合分形地形算法构建起伏地形基体模型;最后,应用特征地貌算法生成符合“尺寸-频率”幂律分布的撞击坑、巨石及石块,并通过柏林噪声增强真实性。以433 Eros为例进行验证,对比物理参数与形貌数据确认方法的可靠性;将其扩展应用于43 Ariadne及2016 HO3,构建“光学数据-基体模型-形貌模拟”全流程实验。仿真表明,该方法在精度、速度与成本间取得平衡,为批量化生成受光学数据约束的小行星三维形貌拟真模型提供了技术支撑。 展开更多
关键词 光变反演 LOOP细分 分形技术 特征地貌 小行星
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植物病原丝状真菌中糖苷水解酶GH12研究进展
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作者 韩长志 黄垠凌 《西南农业学报》 北大核心 2025年第12期2580-2590,共11页
糖苷水解酶12(glycoside hydrolase 12,GH12)家族是一类广泛存在于自然界中的酶类,在纤维素降解、木聚糖降解、植物细胞壁代谢、病原菌侵染及共生关系等生物过程中发挥关键作用。该家族酶的三维结构以β-折叠桶为核心,具有高度保守的活... 糖苷水解酶12(glycoside hydrolase 12,GH12)家族是一类广泛存在于自然界中的酶类,在纤维素降解、木聚糖降解、植物细胞壁代谢、病原菌侵染及共生关系等生物过程中发挥关键作用。该家族酶的三维结构以β-折叠桶为核心,具有高度保守的活性位点和底物结合槽,这种结构特征决定了其对底物的特异性水解能力,并在不同生物来源中表现出一定的多样性。GH12家族酶采用保留型机制进行催化,其催化机制已通过晶体结构解析、突变试验和计算模拟得到充分验证。此外,酶结构中的Loop环及关键氨基酸残基在催化过程中发挥重要作用,可能影响酶的底物特异性、催化效率及稳定性。通过阐述GH12家族的成员及结构、功能、位置及作用机制,对GH12在稻瘟病菌、黑曲霉以及大丽轮枝菌等重要植物病原丝状真菌的研究情况进行梳理,并从不同真菌中GH12功能研究、GH12酶活性催化机制解析和GH12互作蛋白找寻三方面进行展望,以期为深入理解植物病原丝状真菌致病机制的研究提供新思路。 展开更多
关键词 糖苷水解酶12家族 三维结构 催化机制 Loop环
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