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Polydopamine-modified metal-organic frameworks nanoparticles enhance the corrosion resistance and bioactivity of polycaprolactone coating on high-purity magnesium

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Journal of Magnesium and Alloys 2024年第5期12卷 2070-2089页

作者： Qingyun Fu Shaojie He Junjie Yang Ziyu Su Ping Li Xincheng Yu Weihong Jin Shulan Xu Zhentao Yu dingsheng zha Center of Oral Implantology Stomatological HospitalSouthern Medical UniversityGuangzhouChina Panyu Hospital of Chinese Medicine Guangzhou 511400China Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou 510632China First Affiliated Hospital of Jinan University Guangzhou 510630China

Biodegradable magnesium(Mg)and its alloys exhibit excellent biocompatibility and mechanical compatibility,demonstrating tremendous potential for applications in ***,the rapid degradation rate has limited their clinical ***(PCL)is commonly employed as a polymer coating to impede the rapid degradation of ***,its long-term anti-corrosion capability and bioactivity are *** address these issues,polydopamine(PDA)-modified zeolitic imidazolate framework-8(PZIF-8)bioactive nanoparticles are fabricated and incorporated into the PCL *** PZIF-8 particles,featuring catechol motifs,can enhance the compactness of the PCL coating,reduce its defects,and possess biomineralization ability,thereby effectively improving its anti-corrosive and bioactive ***,the active substances released from the degradation of the PZIF-8 particles such as Zn^(2+)and PDA are beneficial for *** corrosion tests indicate that the corrosion current density of PCL-treated sample decreases by more than one order of magnitude and the amount of H_(2)released decreases from 0.23±0.12 to 0.08±0.08 ml cm^(-2)after doping with the ***,the improved corrosion resistance and released PDA and Zn^(2+)from the coating can promote osteogenic differentiation by up-regulating the expression of alkaline phosphatase activity,related osteogenic genes,and *** addition,in vivo implantation experiments in rabbit femur defects further offer strong evidence that the doping of PZIF-8 nanoparticles accelerates bone reconstruction of the PCL *** summary,this work implies a new strategy to fabricate a PCL-based coating on Mg-based implants by introducing the PZIF-8 particles for orthopedic applications.

关键词： Polydopamine ZIF-8 High-purity magnesium Polycaprolactone coating Anticorrosion Bone regeneration

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创伤性脊髓损伤预后的危险因素分析

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中华创伤骨科杂志 2024年第7期26卷 590-596页

作者：贺少杰赵振宇余信诚李伟宽孔畅马航展查丁胜暨南大学附属第一医院骨科广州510630 广州市番禺区中医院骨科广州511400 暨南大学附属顺德医院骨科佛山528303

目的分析创伤性脊髓损伤(TSCI)后6个月预后的危险因素。方法回顾性分析2017年1月至2021年8月暨南大学附属第一医院骨科收治的133例TSCI患者资料。根据患者损伤后6个月较入院时脊髓损伤美国脊髓损伤协会(ASIA)分级的改善情况分为改善组(n... 详细信息

目的分析创伤性脊髓损伤(TSCI)后6个月预后的危险因素。方法回顾性分析2017年1月至2021年8月暨南大学附属第一医院骨科收治的133例TSCI患者资料。根据患者损伤后6个月较入院时脊髓损伤美国脊髓损伤协会(ASIA)分级的改善情况分为改善组(n=82)与非改善组(n=51)。纳入两组患者的性别、年龄、MRI脊髓信号改变长度、最大椎管压迫度(MCC)、最大脊髓压迫度(MSCC)、脑与脊髓损伤中心(BASIC)分级、伤后3 d内中性粒细胞与淋巴细胞计数比值(NLR)、伤后3 d内ASIA分级、术后3 d平均动脉压(MAP)、是否发生并发症等指标进行单因素和logistic回归分析,分析TSCI患者损伤后6个月预后的危险因素。结果单因素分析结果:改善组患者的MRI脊髓信号改变长度、MCC、MSCC、BASIC分级、伤后3 d内NLR、伤后3 d内ASIA分级、术后3 d MAP、有无发生并发症与非改善组比较,差异均有统计学意义(P<0.05)。logistic回归分析结果:伤后3 d内NLR(OR=0.463,95%CI:0.287~0.748,P=0.002)和伤后3 d内ASIA分级(OR=11.684,95%CI:1.684~81.086,P=0.013)、术后3 d MAP(OR=2.224,95%CI:1.306~3.787,P=0.003)是TSCI患者损伤后6个月预后的危险因素。结论对于TSCI患者,伤后3 d内NLR、ASIA分级、术后3 d MAP是伤后6个月预后的危险因素。

关键词：创伤性脊髓损伤预后相关因素

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颈椎类风湿性关节炎的临床特点及诊疗进展

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中国临床解剖学杂志 2024年第1期42卷 104-108页

作者：余信诚查丁胜贺少杰赵振宇蔡兴达暨南大学附属第一医院骨科广州510630 暨南大学附属顺德医院骨科广东佛山528305 广州市番禺区中医院骨科广州511401

类风湿性关节炎(rheumatoid arthritis,RA)是一种慢性侵袭性的自身免疫性疾病,据相关统计,发达国家发病率0.5%~1.0%,我国略低,约占0.28%~0.36%,主要见于35~50岁群体[1,2],女性多见,约43%~88%的患者存在颈椎受累[3],是颈椎最常见的炎性疾... 详细信息

类风湿性关节炎(rheumatoid arthritis,RA)是一种慢性侵袭性的自身免疫性疾病,据相关统计,发达国家发病率0.5%~1.0%,我国略低,约占0.28%~0.36%,主要见于35~50岁群体[1,2],女性多见,约43%~88%的患者存在颈椎受累[3],是颈椎最常见的炎性疾病,其中寰枕关节(atlanto-occipitaljoint,AOJ)和寰枢关节(atlanto-axialjoint,AAJ)是唯一没有椎间盘的椎体节段,仅由滑膜关节组成,受RA影响最大[4]。

关键词：颈椎关节炎类风湿关节不稳

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Geometric Error Identification of Gantry-Type CNC Machine Tool Based on Multi-Station Synchronization Laser Tracers

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 150-162页

作者： Jun zha Huijie zhang School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Academy Suzhou 215123China

Laser tracers are a three-dimensional coordinate measurement system that are widely used in industrial *** propose a geometric error identification method based on multi-station synchronization laser tracers to enable the rapid and high-precision measurement of geometric errors for gantry-type computer numerical control(CNC)machine *** method also improves on the existing measurement efficiency issues in the single-base station measurement method and multi-base station time-sharing measurement *** consider a three-axis gantry-type CNC machine tool,and the geometric error mathematical model is derived and established based on the combination of screw theory and a topological analysis of the machine kinematic *** four-station laser tracers position and measurement points are realized based on the multi-point positioning principle.A self-calibration algorithm is proposed for the coordinate calibration process of a laser tracer using the Levenberg-Marquardt nonlinear least squares method,and the geometric error is solved using Taylor’s first-order linearization *** experimental results show that the geometric error calculated based on this modeling method is comparable to the results from the Etalon laser *** a volume of 800 mm×1000 mm×350 mm,the maximum differences of the linear,angular,and spatial position errors were 2.0μm,2.7μrad,and 12.0μm,respectively,which verifies the accuracy of the proposed *** research proposes a modeling method for the precise measurement of errors in machine tools,and the applied nature of this study also makes it relevant both to researchers and those in the industrial sector.

关键词： Multi-point positioning Multi-station synchronization CNC machine tool Geometric error Error separation

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Identification of the Hammerstein nonlinear system with noisy output measurements

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Control Theory and Technology 2024年第2期22卷 203-212页

作者： Qiming zha Feng Li Ranran Liu School of Electrical and Information Engineering Jiangsu University of TechnologyChangzhou213001JiangsuChina School of Automobile and Traffic Engineering Jiangsu University of TechnologyChangzhou213001JiangsuChina

In this research, we present a methodology to identify the Hammerstein nonlinear system with noisy output measurements. The Hammerstein system presented is comprised of neural fuzzy model (NFM) as its static nonlinear block and auto-regressive with extra input (ARX) model as its dynamic linear block, and a two-step procedure is accomplished using signal combination. In the first step, in the case of input–output of Gaussian signals, the correlation function-based least squares (CF-LS) technique is utilized to identify the linear block, solving the problem that the intermediate variable connecting nonlinear and linear blocks cannot be measured. In the second step, to improve the identification accuracy of the nonlinear block parameters, an improved particle swarm optimization technique is developed under input–output of random signals. The validity and accuracy of the presented scheme are verified by a numerical simulation and a practical nonlinear process, and the results illustrate that the proposed methodology can identify well the Hammerstein nonlinear system with noisy output measurements.

关键词： Hammerstein nonlinear system Signal combination Auto-regressive with extra input Improved particle swarm optimization

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Preparing cyclic polymers at high concentrations via self-folding cyclization technique by adjusting the contents of hydrophilic units in linear precursors

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Chinese Chemical Letters 2024年第2期35卷 283-288页

作者： Hao zha Zuowei Wang Chao Liu Chunyan Hong Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Cyclic polymers are a class of polymers that feature endless topology,and the synthesis of cyclic polymers has attracted the attention of many ***,cyclic polymers were efficiently constructed by self-folding cyclization technique at high *** poly((oligo(ethylene glycol)acrylate)-co-(dodecyl acrylate))(P(OEGA-co-DDA))precursors with different ratios of hydrophilic and hydrophobic moieties were synthesized by reversible addition-fragmentation chain transfer(RAFT)polymerization using a bifunctional chain transfer agent with two anthryl end *** amphiphilic linear precursors underwent the self-folding process to generate polymeric nanoparticles in *** irradiating the aqueous solution of the nanoparticles with 365 nm UV light,cyclic polymers were synthesized successfully via coupling of anthryl *** effects of the ratios of hydrophilic and hydrophobic moieties in linear P(OEGA-co-DDA)copolymers and polymer concentration on the purity of the obtained cyclic polymers were explored in detail via ^(1)H nuclear magnetic resonance(^(1)H NMR),dynamic light scattering(DLS),UV‒visible(vis)analysis,three-detection size exclusion chromatography(TD-SEC)and transmission electron microscopy(TEM).It was found that by adjusting the content of the hydrophilic segments in linear precursors,single chain polymeric nanoparticles(SCPNs)can be generated at high polymer ***,cyclic polymers with high purity can be constructed *** method overcomes the limitation of traditional ring-closure method,which is typically conducted in highly dilute conditions,providing an efficient method for the scalable preparation of cyclic polymers.

关键词： Cyclic polymers Self-folding cyclization technique Single chain polymeric nanoparticles RAFT polymerization Direct visualization

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Underwater four-quadrant dual-beam circumferential scanning laser fuze using nonlinear adaptive backscatter filter based on pauseable SAF-LMS algorithm

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Defence Technology（防务技术） 2024年第7期37卷 1-13页

作者： Guangbo Xu Bingting zha Hailu Yuan Zhen Zheng He zhang Ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjing 210094China Science and Technology on Electromechanical Dynamic Control Laboratory Beijing 100081China Shanghai Radio Equipment Research Institute Shanghai 201109China

The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser *** overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering *** enhances the algorithm loading capability of the *** order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)*** also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the ***,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo *** experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm

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Efficient synthesis of bottle-brush polymers enabled by selective photoactivation strategy in NIR-induced PET-RAFT polymerization

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Science China Chemistry 2024年第7期67卷 2353-2361页

作者： Hao zha Lin Cheng Zuowei Wang Chao Liu Chunyan Hong Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China

Bottle-brush polymers possessing densely grafted side chains have special properties that are distinct from linear ***,an efficient method for preparing bottle-brush polymers based on a selective photoactivation strategy in the photoinduced electron/energy transfer reversible addition-fragmentation chain transfer(PET-RAFT)polymerization was developed.A methacrylate monomer 2-(2-(dodecylthiocarbonothioylthio)propionate)ethyl methacrylate(DTPEMA)containing a 2-(dodecylthiocarbonothioylthio)propionate(DTP)unit with a secondary R group was *** the unique selectivity of metal naphthalocyanine photocatalyst zinc 2,11,20,29-tetra-tert-butyl-2,3-naphthalocyanine(ZnTtBNc)toward trithiocarbonate with tertiary R group,the PET-RAFT polymerization of DTPEMA catalyzed by ZnTtBNc was performed under near infrared(NIR)light(λ_(max)=760 nm)irradiation at room temperature,using 4-cyano-4-[(dodecylsulfanylthiocarbonyl)-sulfanyl]pentanoic acid(CDTPA)with a tertiary R group as a chain transfer agent(CTA).Proton nuclear magnetic resonance(1H NMR)and gel permeation chromatography(GPC)results demonstrated that the DTP units in the side chains were inert during the *** grafting poly(methyl acrylate)(PMA)from PDTPEMA via thermal-initiated RAFT polymerization,welldefined P(DTPEMA-g-PMA)bottle-brush polymers could be ***,the film prepared from the bottle-brush polymer exhibited excellent scratch self-healing property due to the interlocking of side chains.

关键词： bottle-brush polymers PET-RAFT polymerization selective photoactivation scratch self-healing

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低强度复合振动治疗去卵巢老龄大鼠骨质疏松实验研究

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中国运动医学杂志 2011年第3期30卷 265-269,274页

作者：邓轩赓陈建庭查丁胜四川省骨科医院脊柱病区四川成都610041 南方医科大学南方医院脊柱骨病科

目的:观察低强度复合振动对去卵巢老龄大鼠骨质疏松的治疗作用。方法:13月龄SD雌性经产大鼠16只,随机均分为对照组和实验组。卵巢摘除法骨质疏松造模,3个月后检查骨密度(BMD)下降后实验组接受低强度复合振动(振动频率45 Hz～55 Hz,振动... 详细信息

目的:观察低强度复合振动对去卵巢老龄大鼠骨质疏松的治疗作用。方法:13月龄SD雌性经产大鼠16只,随机均分为对照组和实验组。卵巢摘除法骨质疏松造模,3个月后检查骨密度(BMD)下降后实验组接受低强度复合振动(振动频率45 Hz～55 Hz,振动强度0.12 g～0.21 g,g=9.8 m/s2,20分钟/次/天,5天/周),对照组不进行振动治疗。13周复合振动实验结束后分别活体测量两组大鼠腰椎、股骨骨密度(Lorland XR-46),胫骨标本骨微结构扫描分析(SCANCO u-CT),测试腰椎、股骨标本力学性能(858 mini bionix)及酶法检测血清碱性磷酸酶、非前列腺酸性磷酸酶,电化学发光免疫法检测血清骨钙素和I型胶原C端交联肽。结果:复合振动实验结束后实验组腰椎和股骨BMD较实验前显著增加(分别增加0.0110±0.0048 g/cm2,P=0.000和0.0056±0.0065 g/cm2,P=0.004),而对照组显著下降(分别下降0.0071±0.0042 g/cm2和0.0073±0.0063 g/cm2)。相较对照组,骨微结构参数Tb.N显著增加(P=0.002)、***显著降低(P=0.005)以及BV/TV显著增加(P=0.048),腰椎、股骨强度极限也显著增加(P=0.038,P=0.014),但血清骨钙素、碱性磷酸酶、I型胶原C端交联肽、非前列腺酸性磷酸酶两组无统计学差异。结论:低强度复合振动可以减轻去卵巢老龄大鼠骨质疏松程度,提高骨质疏松大鼠骨质量。

关键词：骨质疏松大鼠复合振动

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Reinforcement Learning Navigation for Robots Based on Hippocampus Episode Cognition

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Journal of Bionic Engineering 2024年第1期21卷 288-302页

作者： Jinsheng Yuan Wei Guo Zhiyuan Hou Fusheng zha Mantian Li Pengfei Wang Lining Sun State Key Laboratory of Robotics and System Harbin Institute of Technology(HIT)Harbin 150001China Shenzhen Academy of Aerospace Technology Shenzhen 518057China School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

Artificial intelligence is currently achieving impressive success in all ***,autonomous navigation remains a major challenge for *** learning is used for target navigation to simulate the interaction between the brain and the environment at the behavioral level,but the Artificial Neural Network trained by reinforcement learning cannot match the autonomous mobility of humans and *** hippocampus–striatum circuits are considered as key circuits for target navigation planning and *** paper aims to construct a bionic navigation model of reinforcement learning corresponding to the nervous system to improve the autonomous navigation performance of the *** ventral striatum is considered to be the behavioral evaluation region,and the hippocampal–striatum circuit constitutes the position–reward *** this paper,a set of episode cognition and reinforcement learning system simulating the mechanism of hippocampus and ventral striatum is constructed,which is used to provide target guidance for the robot to perform autonomous *** with traditional methods,this system reflects the high efficiency of learning and better Environmental *** research is an exploration of the intersection and fusion of artificial intelligence and neuroscience,which is conducive to the development of artificial intelligence and the understanding of the nervous system.

关键词： Episode cognition Reinforcement learning Hippocampus Robot navigation

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