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腋拐的使用角度对人机舒适性的影响研究

机械设计与制造 2024年第10期 251-254页

作者：吕春梅唐艳红李美杨帆东北大学机械工程与自动化学院辽宁沈阳110819

目前单臂操作助行器具产品的舒适性评价标准体系不完善,产品设计过程中缺乏充分的生物力学及人机工程学分析,从而导致了诸如腋神经损伤、腕关节损伤等二次伤害的发生。结合人机工程学理论和实验,通过人体生理结构解剖分析、使用动作姿... 详细信息

目前单臂操作助行器具产品的舒适性评价标准体系不完善,产品设计过程中缺乏充分的生物力学及人机工程学分析,从而导致了诸如腋神经损伤、腕关节损伤等二次伤害的发生。结合人机工程学理论和实验,通过人体生理结构解剖分析、使用动作姿态分析、简易模型受力分析及使用舒适性主客观实验结合分析等方法,研究腋下拐杖各参数对人机舒适性的影响,得出腋下拐杖对人体使用舒适性产生影响的角度参数的最佳范围,为后续腋拐的设计与创新研究提供参考和借鉴。

关键词：人机工程学拐杖舒适性主观评价客观评价

Keap1-Nrf2-ARE信号通路与糖尿病视网膜病变的相关性研究进展

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医学信息 2024年第10期37卷 189-192页

作者：唐艳红苏梅贵临夏州中医医院眼科

糖尿病视网膜病变（DR）是糖尿病并发症中最常见的微血管病变，是我国糖尿病（DM）患者视力下降甚至致盲的主要原因。近年来研究发现，氧化应激是DR的发病机制之一，而Kelch样环氧氯丙烷相关蛋白-1 (Keap1)-核因子E2相关因子2(Nrf2)-抗... 详细信息

糖尿病视网膜病变（DR）是糖尿病并发症中最常见的微血管病变，是我国糖尿病（DM）患者视力下降甚至致盲的主要原因。近年来研究发现，氧化应激是DR的发病机制之一，而Kelch样环氧氯丙烷相关蛋白-1 (Keap1)-核因子E2相关因子2(Nrf2)-抗氧化反应元件（ARE）信号通路是机体最重要的内源性抗氧化应激通路。故本文就Keap1-Nrf2-ARE信号通路与氧化应激、DR之间的相关性作一综述。

关键词： Keap1-Nrf2-ARE信号通路糖尿病视网膜病变氧化应激

Evapotranspiration and Its Energy Exchange in Alpine Meadow Ecosystem on the Qinghai-Tibetan Plateau

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Journal of Integrative Agriculture 2013年第8期12卷 1396-1401页

作者： LI Jie JIANG Sha WANG Bin JIANG Wei-wei tang yan-hong DU Ming-yuan GU Song College of Life Science Nankai University National Institute for Environmental Studies National Institute for Agro-Environmental Sciences

To understand the water and energy exchange on the Qinghai-Tibetan Plateau, we explored the characteristics of evapotranspiration （ET） and energy fluxes from 2002 to 2005 over a Kobresia meadow ecosystem using the eddy covariance method. The ratio of annual ET to precipitation （P） of meadow ecosystem was about 60%, but varied greatly with the change of season from summer to winter. The annual ET/P in meadow was lower than that in shrub, steppe and wetland ecosystems of this plateau. The incident solar radiation （Rs） received by the meadow was obviously higher than that of lowland in the same latitude; however the ratio of net radiation （Rn） to Rs with average annual value of 0.44 was significantly lower than that in the same latitude. The average annual ET was about 390 mm for 2002-2005, of which more than 80% occurred in growing season from May to September. The energy consumed on the ET was about 44% of net radiation in growing season, which was lower than that of shrub, steppe and wetland on this plateau. This study demonstrates that the Kobresia meadow may prevent the excessive water loss through evapotranspiration from the ecosystem into the atmosphere in comparison to the shrub, steppe and wetland ecosystems of the Qinghai-Tibetan Plateau.

关键词： eddy covariance evapotranspiration net radiation precipitation Qinghai-Tibetan Plateau

Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang Liu hong-wu tang Sai-yu Yuan Jing yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

Synthesis and curing of a novel amino-containing phthalonitrile derivative

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Chinese Chemical Letters 2007年第5期18卷 523-526页

作者： Ke Zeng Ke Zhou Wen Rui tang yan tang hong Fei Zhou Tao Liu Yi Peng Wang Hai Bing Zhou Gang yang State Key Laboratory of Polymer Materials Engineering College of Polymer Science and Engineering Sichuan University Chengdu 610065 China

A novel phthalonitrile derivative containing an amino group, 3,5-bis（3,4-dicyanophenoxy）aniline （CPA）, was synthesized via a nucleophilic displacement of 4-nitrophthalonitrile and 5-aminoresorcinol hydrochloride. The structure of CPA was confirmed by Fourier transform infrared spectra （FT-IR） and nuclear magnetic resonance （^1H NMR）. Thermal analysis performed on CPA revealed that the novel phthalonitrile derivative showed a self-promotion curing behavior and the resulting polymer exhibited outstanding heat-resistance.

关键词： Phthalonitrfle derivative Amino group Self-promotion curing behavior

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虾青素对大鼠心肌梗死后心肌纤维化的影响

中南药学 2024年第7期22卷 1767-1771页

作者：余太辉鲁锦国唐艳红方婷婷湖北省中西医结合医院心血管内科武汉430015 武汉大学人民医院心血管内科武汉430060

目的探讨虾青素对大鼠心肌梗死后心肌纤维化的影响及可能机制。方法心肌梗死组和天然虾青素组大鼠结扎冠脉血管前降支制成心肌梗死模型;而假手术组仅开胸处理不结扎冠脉血管。虾青素组在术前一日开始按100 mg/(kg·d)剂量灌胃虾青素。... 详细信息

目的探讨虾青素对大鼠心肌梗死后心肌纤维化的影响及可能机制。方法心肌梗死组和天然虾青素组大鼠结扎冠脉血管前降支制成心肌梗死模型;而假手术组仅开胸处理不结扎冠脉血管。虾青素组在术前一日开始按100 mg/(kg·d)剂量灌胃虾青素。而心肌梗死组和假手术组灌胃等量的蒸馏水。在28 d后用Masson染色检测心肌纤维化并计算胶原容积分数,采用Western blot检测心肌梗死周边的Ⅰ型胶原蛋白、MMP-9及p38通路蛋白的表达情况。结果与心肌梗死对照组相比,虾青素组的胶原容积分数明显减少,Ⅰ型胶原蛋白、MMP-9蛋白、磷酸化p38的表达明显减少。结论虾青素可能通过抑制p38的磷酸化从而抑制心肌梗死周边的心肌纤维化。

关键词：虾青素心肌梗死心肌纤维化 p38

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常州市青少年电子烟使用倾向及影响因素分析

江苏预防医学 2024年第1期35卷 37-40页

作者：唐红艳赵晓军顾昕王珮岳文彬陆洋常州市疾病预防控制中心江苏常州213022 江苏省疾病预防控制中心

目的分析常州市青少年环境烟草暴露、电子烟使用倾向及其可能的影响因素,为开展青少年电子烟早期干预提供依据。方法采用分层多阶段整群概率抽样法,2019年、2021年分别抽取常州市主城区初中、普高、职高的学生进行问卷调查。结果2019年... 详细信息

目的分析常州市青少年环境烟草暴露、电子烟使用倾向及其可能的影响因素,为开展青少年电子烟早期干预提供依据。方法采用分层多阶段整群概率抽样法,2019年、2021年分别抽取常州市主城区初中、普高、职高的学生进行问卷调查。结果2019年、2021年电子烟使用倾向比例分别为11.7%、11.6%,二手烟暴露比例分别为72.8%、67.2%,电子烟广告暴露比例分别为25.7%、34.0%。调整年份、性别、年龄等因素后,多因素logistic分析显示,尝试过电子烟(OR=23.285,95%CI:12.658~42.833)、朋友吸烟(OR=2.516,95%CI:1.706~3.710)、二手烟暴露(OR=1.885,95%CI:1.215~2.924)、认为吸烟更有吸引力(OR=2.101,95%CI:1.040~4.247)、对社交场合吸烟无感(OR=2.309,95%CI:1.381~3.843)的青少年电子烟使用倾向较高;认为吸烟会减少吸引力的青少年使用电子烟的风险较低(OR=0.448,95%CI:0.301~0.668)。结论青少年电子烟使用倾向比例较高,需强化电子烟广告监管,通过同伴教育、广泛的社会宣传等方式纠正其吸烟行为。

关键词：电子烟青少年认知态度行为

Model-driven path planning for robotic plasma cutting of branch pipe with single Y-groove based on pipe-rotating scheme

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Advances in Manufacturing 2024年第1期12卷 94-107页

作者： yan Liu Qiu tang Xin-Cheng Tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

Analyzing topics in social media for improving digital twinning based product development

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Digital Communications and Networks 2024年第2期10卷 273-281页

作者： Wenyi tang Ling Tian Xu Zheng Ke yan School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

Digital twinning enables manufacturers to create digital representations of physical entities,thus implementing virtual simulations for product *** efforts of digital twinning neglect the decisive consumer feedback in product development stages,failing to cover the gap between physical and digital *** work mines real-world consumer feedbacks through social media topics,which is significant to product *** specifically analyze the prevalent time of a product topic,giving an insight into both consumer attention and the widely-discussed time of a *** primary body of current studies regards the prevalent time prediction as an accompanying task or assumes the existence of a preset ***,these proposed solutions are either biased in focused objectives and underlying patterns or weak in the capability of generalization towards diverse *** this end,this work combines deep learning and survival analysis to predict the prevalent time of *** propose a specialized deep survival model which consists of two *** first module enriches input covariates by incorporating latent features of the time-varying text,and the second module fully captures the temporal pattern of a rumor by a recurrent network ***,a specific loss function different from regular survival models is proposed to achieve a more reasonable *** experiments on real-world datasets demonstrate that our model significantly outperforms the state-of-the-art methods.

关键词： Digital twinning Product development Topic analysis Social media