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Optimal Design of Bicycle Frame Parameters Considering Biomechanics

Chinese Journal of Mechanical Engineering 2011年第1期24卷 141-145页

作者： XIANG Zhongxia xu ruifen.BU Yan WU Xiaofan School of Mechanical Engineering Tianjin University Tianjin 300072 China School of Electromechanical Engineering Guangdong University of Technology Guangzhou 510006 China

With the development of technology and the change of market demands,the trend in middle and high grade bicycle manufacturing is developed toward small-volume,multi-species,and customer-oriented ***,human element should be fully considered in design so that the bicycle has the best cycling performance for the specific ***,customized design is difficult to achieve since feature parameters of the rider are not included in the *** design of bicycle frame is the most important in bicycle *** relative positions among the saddle,handlebar and central axis are defined as the bicycle three-pivot,they are the main parameters in bicycle frame *** conventional bicycle design,frame parameters are merely relevant to bicycle *** the basis of the principles of biomechanics and ergonomics knowledge,this paper presents a design method for bicycle three-pivot considering feature parameters of the rider by dynamic ***,a dynamic model of rider-bicycle system is built for a special rider,and a serial of simulation experiments is designed by uniform test ***,a mathematical model is built between the three-pivot position and the square of lower limb muscle stress by using simulation and regression analysis of the rider-bicycle *** optimal three-pivot position parameters are obtained by setting the minimal of the square of the lower limb muscle stress as the ***,the optimal parameters are gained for the specific ***,various results are gained for different riders based on the same design *** function between feature parameters of the rider and the optimum three-pivot position parameters is built by *** design considering biomechanics can be divided into three main steps：calculating the three-pivot position,designing the geometrical structure of the bicycle frame and analyzing frame strength,and selecting appropriate parts and assembling the *** des

关键词： bicycle design biomechanics muscle fatigue feature parameters of the rider

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Natural anti-oxLDL IgM monoclonal antibody in the pathogenesis of atherosclerosis

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Journal of Geriatric Cardiology 2009年第1期6卷 42-48页

作者： xuyang Feng ruifen.xu Yan Gao Haokao Gao Zheng He Haichang Wang Department of Cardiology Xijing Hospital Xi''an 710032 China Department of Anesthesiology Stomatology Hospital the Fourth Military Medical University Xi''an 710000 P.R.China Department of Cardiology PLA No. 323 Hospital Xi''an 710054 P.R.China Department of Cardiology Xijing Hospital Xi''an 710032 China Department of Cardiology Xijing Hospital Xi''an 710032 China

Objective To explore the role and the possible molecular mechanisms of natural anti-oxLDL IgM monoclonal antibody played and involved in pathogenesis of atherosclerosis. Methods Natural anti-oxLDL IgM monoclonal antibody 3A6 was generated by using standard hybridoma production techniques. Influence of 3A6 on formation of foam cells was observed by Oil Red O staining and affinity of Na125I-conjugated oxLDL on the naive and LPS-activated macrophages. After LPS stimulation on macrophages, anti-TLR4 neutralizing mAb, p38MAPK specific inhibitor SB203580, NF-kB specific inhibitor PDTC or RNAi targeting Fcα/μ receptor (Fcamr) were applied, respectively. Results Natural anti-oxLDL IgM monoclonal antibody 3 A6 were found specifically inhibit the binding of CuoxLDL to naive macrophages but not the binding of CuoxLDL to LPS-activated macrophages. It also promoted the formation of CuoxLDL-mediated foam macrophages. 3A6 F(ab')2 or pre-incubation with un-related IgM inhibited the binding of 3A6/CuoxLDL complex to LPS-activated macrophages. LPS up-regulated the expression of Fcamr in macrophages in a dose- and time-dependent manner, which was attenuated by treatment with anti-TLR4. LPS induced the phosphorylation of p38MAPK and translocation of NF-kB p65, contributing to the up-regulated expression of Fcα/μ receptor in macrophages. Conclusions Natural anti-oxLDL IgM monoclonal antibody 3A6 specifically inhibited the binding of CuoxLDL to naive macrophages in vitro. However, LPS, through the Toll-like receptor (TLR)4 receptor, activated the p38MAPK and NF-kB pathways and up-regulated the expression of Fcα/μ receptor in macrophages, which promoted the binding of 3A6/CuoxLDL complex to macrophages through binding with Fc fragments and the formation of foam macrophages. Therefore, our findings provide a new explanation why bacterial infection deteriorates the pathogenesis of atherosclerosis.

关键词： Atherosclerosis macrophage immunoglobulin M Toll-like receptor 4 oxidized low-density lipoprotein Fcα/μ receptor

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Factors Affecting the Classroom Oral Participation of Teacher-learners

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Sino-US English Teaching 2006年第7期3卷 58-62页

作者： ruifen.xu Guangdong Institute of Education

With quantitative method, this paper attempts to figure out in L2 motivation perspective the factors that affect the classroom oral participation of the teacher-learners in their further education. The findings obtained after a correlation study of the relationship between the learners＇ oral participation and the factors in the levels of language, learner and learning situation indicate that self-perceived competence and desire to communicate display greater correlation with participation. This paper also puts forwards some suggestions on how to improve learners＇ self-perceived competence and promote their desire to communicate in class.

关键词： motivation self-perceived competence desire to communicate factors

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Distribution Assessment and Source Identification Using Multivariate Statistical Analyses and Artificial Neutral Networks for Trace Elements in Agricultural Soils in Xinzhou of Shanxi Province, China

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Pedosphere 2018年第3期28卷 542-554页

作者： SHANGGUAN Yuxian CHENG Bin ZHAO Long HOU Hong MA Jin SUN Zaijin xu Yafei ZHAO ruifen.ZHANG Yigong HUA Xiaozan HUO Xiaolan ZHAO Xiufeng State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012( China) Institute of Agricultural Environment and Resources Shanxi Academy of Sciences Key Laboratory of Soil Environment and Nutrient Resources of Shanxi Province Taiyuan 030031( China)

Multivariate statistical analyses were used to assess the contents and distributions of trace elements in agricultural soils in Xinzhou of Shanxi Province, China, and to identify their sources. Samples with high levels of trace elements were concentrated in eastern Xinzhou, with contents declining from the east to west. Principal component and redundancy analyses revealed strong correlations among Co, Cu, Mn, Ni, Se, V, and Zn contents, suggesting that these elements were derived from similar parent materials. There were also strong correlations between the contents of these elements and soil properties. Contents of Cd and Pb were significantly higher in the agricultural soil samples than in the background soil samples(P < 0.05), and were higher in areas with higher levels of gross domestic product but decreased with distance to the nearest road. Therefore, human activities appear to have a strong influence on the Cd and Pb distribution patterns. A novel artificial neural network(ANN) model, using environmental input data, was used to predict the soil Cd and Pb contents of specified test dates. The performances of the ANN model and a traditional multilinear model were compared. The ANN model could successfully predict Cd and Pb content distributions, projecting that soil Cd and Pb contents will increase by 128% and 25%, respectively, by 2020. The results thus indicated that the economic condition of an area has a greater effect on trace element contents and distributions in the soil than the scale of the economy itself.

关键词： contamination enrickment factor keavy metal prediction principal component analysis redundancy analysis

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Genomic evidence of lung carcinogenesis associated with coal smoke in xuanwei area, China

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National Science Review 2021年第12期8卷 15-19页

作者： Honglei Zhang Chao Liu Li Li xu Feng Qing Wang Jihua Li Shaobin xu Shuting Wang Qianlu Yang Zhenghai Shen Jinhua Su Xiaosan Su ruifen.Sun xuhong Zhou Junliang Wang Yongchun Zhou Baowei Jiao Wanbao Ding Xianbao Cao Yue Wang Yunchao Huang Lianhua Ye Center for Scientific Research Yunnan University of Chinese Medicine Department of Nuclear Medicine Third Affiliated Hospital of Kunming Medical UniversityYunnan Cancer Hospital Biotherapy Center Third Affiliated Hospital of Kunming Medical University Yunnan Cancer Hospital Department of Oncology Qujing First People's Hospital Qujing Center for Disease Control and Prevention Supercomputing Platform of Kunming Institute of Zoology Kunming Biological Diversity Center of Instruments Kunming Institute of Zoology Chinese Academy of Sciences Department of Thoracic Surgery Ⅱ Third Affiliated Hospital of Kunming Medical University Yunnan Cancer Hospital Department of Thoracic Surgery Ⅰ Third Affiliated Hospital of Kunming Medical University Yunnan Cancer Hospital Department of Thoracic Surgery Xuanwei People's Hospital State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases Kunming Institute of Zoology Chinese Academy of Sciences Department of Oncology Yan'an Affiliated Hospital of Kunming Medical University Department of Otolaryngology First People's Hospital of Yunnan Province the Affiliated Hospital of Kunming University of Science and Technology The Affiliated Hospital of Guizhou Medical University

xuanwei area, in southwestern China,harbors the highest female lung cancer rate in the country(Supplementary Table 1) [1]. Epidemiological studies have shown that lung cancer incidence in xuanwei area is associated with the use of different types of local coal for household cooking and heating [2]. The genomic landscape of xuanwei female adenocarcinoma(XWFA), the most distinctive feature of lung cancer in xuanwei, has yet to be elucidated systematically. Here,we provide the fundamental resource of genomic datasets for further exploration of XWFA molecular mechanisms and development of targetable therapy.

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Sodium Aescinate Alleviates Neuropathic Pain in Rats by Suppressing the TLR4/NF KB Pathway Activation after Paclitaxel Chemotherapy

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Yangtze Medicine 2023年第2期7卷 134-146页

作者： Miao Huo Qian Zhang Ziyu Zhao ruifen.xu Xingxing Zheng Guang Yang Jiao Guo Department of Anesthesiology Shaanxi Provincial People’s Hospital Xi’an China Department of Burn and Plastic Surgery Shaanxi Provincial People’s Hospital Xi’an China

Background: Emerging evidence suggests that chemotherapy-induced peripheral neuropathy (CIPN) is a significant side effect of chemotherapeutic drugs. Many experiments have proved that sodium aescinate (SA) has definite pharmacological effects such as anti-infection, anti-exudation, anti-edema, anti-tumor as well as neuroprotection, and the drug side effects are mild. However, no study has explored whether SA is involved in the analgesic effect of paclitaxel (PAC) induced neuropathic pain in rats. Methods: Rats were given an intraperitoneal injection of PAC (2.5 mg/Kg intraperitoneally on days 1, 3, 5, and 7), while SA 25 mg/kg intraperitoneally was administered daily for 14 consecutive days. The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) of rats were examined on experimental days 3, 5, 7, 11, 14. All rats were sacrificed on day 15 of the experiment, and L4-6 spinal cords were removed. Subsequently, immunohistochemistry, HE staining, ELISA, RT-qPCR, Western blotting were applied to evaluate cytoskeletal protein expression (NF-L and NF-M), spinal nerve structural integrity, proinflammatory factor contents (TNF-α, IL-1β, and IL-6), and protein content of the TLR4/NF-κB pathway, respectively. Results: After the rats developed PAC induced pain behaviors, multiple injections of SA rendered the rats with elevated MWT and TWL values, decreased expression of NF-L and NF-M in the spinal cord, materially downregulated content of proinflammatory factors, and reduced amounts of TLR4 and p-NF-κB protein levels. Conclusions: The results of the present study preliminarily indicate that SA has an analgesic effect on rats with CIPN induced by PAC injection, and the mechanism may be related to blocking the TLR4/NF-κB signaling pathway, inhibiting the expression of proinflammatory factors, and alleviating cytoskeletal disorders.

关键词： Chemotherapy-Induced Peripheral Neuropathy Sodium Aescinate

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Astaxanthin Regulates PPAR-γ/NF-κB Pathway to Mitigate Nerve Injury after Cerebral Ischemia/Reperfusion in Rats

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Journal of Biosciences and Medicines 2022年第9期10卷 294-310页

Purpose: This research evaluates the efficacy of astaxanthin (AX) on cerebral ischemia/reperfusion (I/R) injury in rats and elucidates the potential mechanism of its neuronal protective effect. Methods: Rats were subjected to a middle cerebral artery occlusion/reperfusion (MCAO/R) model. Fifty grown male Sprague-Dawley (SD) rats were divided into 5 groups, including sham operation group (Sham), MCAO/R group, MCAO/R+AX group, MCAO/R+ AX+ Scramble group and MCAO/R+AX+ si-PPAR-γ group. The neurological score and cerebral infarction volume were evaluated after surgery. Rat microglia (RM) were stimulated by lipopolysaccharide (LPS) to form an inflammatory environment. LPS-induced RM cells were incubated with different concentrations of AX (1, 5 or 10 μg/mL), then cell viability, the expression of microglial activation markers, including cytokines (IL-1β, IL-6 and TNF-α), cluster of differentiation 68 (CD68), inducible nitric oxide synthase (iNOS) and CD206 and the expression of PPAR-γ and phosphorylated P65 (p-P65) proteins were determined. Cells were treated with pcDNA-PPAR-γ, as well as treatment with si-PPAR-γ or PPAR-γ antagonist GW9662 before AX treatment, and then cell activation mediators were tested. Results: AX inhibits LPS-induced RM cells activation and enhanced the expression level of PPAR-γ protein in way of dose-dependent, and pcDNA-PPAR-γ treatment had the same effect as AX. While si-PPAR-γ transfection or PPAR-γ suppressant GW9662 treatment reversed the effect of AX, and cut down the level of PPAR-γ protein and augmented the level of p-P65 protein. In addition, AX treatment alleviated the infarct volume, and sensorimotor and cognitive functions of MCAO/R model rats. Conclusion: AX alleviates LPS-induced microglial injury and has a protective effect on rat cerebral I/R injury by regulating the PPAR-γ/NF-κB pathway.

关键词： Astaxanthin Cerebral Ischemia/Reperfusion Injury RM Cells PPAR-γ P65

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On　supplementary　techniques　of　simple　NFT　system　for　growing　tomatoes

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浙江农业学报 1996年第2期 44-47页

作者： MU Yonghua, ZHANG Dewei, xu Zhihao, QUE ruifen.& ZHANG Shizu (Institute of Horticulture, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China)

番茄简易营养液膜栽培的产量和品质均比稻谷壳灰基质栽培有较大的改善。番茄生长中的耗水量与株间温度和池温的相关性分别达到０．０１和０．０５的显著水平。ＮＦＴ栽培床的进水口和出水口产量存在显著差异（０．０５），但在４０ｃｍ... 详细信息

番茄简易营养液膜栽培的产量和品质均比稻谷壳灰基质栽培有较大的改善。番茄生长中的耗水量与株间温度和池温的相关性分别达到０．０１和０．０５的显著水平。ＮＦＴ栽培床的进水口和出水口产量存在显著差异（０．０５），但在４０ｃｍ和８０ｃｍ宽度的栽培床之间的产量并没有差异。同时本文还对番茄开花结果初期营养液中的矿质元素浓度的昼夜变化进行了研究。

关键词：番茄营养液膜技术水分消耗营养产量

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氧化铁对不同有机负荷下餐厨垃圾厌氧消化产气的影响

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环境工程学报 2017年第7期11卷 4258-4264页

作者：周丽丽杨帆罗瑞芬徐期勇北京大学深圳研究生院环境与能源学院聚硅酸盐复合环保材料工程实验室深圳518055

进行了餐厨垃圾(FW)和接种污泥(Ⅰ)基于不同VS比(分别为FW/I=1,FW/I=3,FW/I=5)下的中温厌氧消化实验,对比了不同有机负荷下未添加氧化铁和添加氧化铁对餐厨垃圾厌氧消化产气的影响。结果表明,在FW/I=1时,餐厨垃圾厌氧消化体系的产气情... 详细信息

进行了餐厨垃圾(FW)和接种污泥(Ⅰ)基于不同VS比(分别为FW/I=1,FW/I=3,FW/I=5)下的中温厌氧消化实验,对比了不同有机负荷下未添加氧化铁和添加氧化铁对餐厨垃圾厌氧消化产气的影响。结果表明,在FW/I=1时,餐厨垃圾厌氧消化体系的产气情况主要由接种污泥决定,添加氧化铁仅能在较小的程度上促进体系产甲烷能力提升;而在FW/I=3时,添加氧化铁可以帮助餐厨垃圾厌氧消化体系从低速产甲烷过程快速进入高速产甲烷,快速降解有机质实现稳定化;而对于FW/I=5时添加氧化铁可以解除由于有机负荷过高造成的酸抑制并恢复体系的产甲烷能力。因此,在实际应用厌氧消化技术处理餐厨垃圾中可以通过添加氧化铁来提高其有机负荷(OLR),提高处理效率,保证餐厨垃圾厌氧消化的正常运行和促进甲烷的产生。

关键词：餐厨垃圾厌氧消化氧化铁有机负荷

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标记理论与英语瞬间动词习得中的母语迁移

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新疆教育学院学报 2006年第3期22卷 132-135页

作者：许瑞芬广东教育学院外语系广东广州510303

Eckman(1977)的“标记差异假说”指出,目标语结构的标记性比母语对应结构更强的情况下,迁移同样可能发生。英汉两种语言都有瞬间性动词。通过对比发现,英语瞬间性动词的标记程度更强。练习卷的完成情况表明：不同层次的英语学习者在使... 详细信息

Eckman(1977)的“标记差异假说”指出,目标语结构的标记性比母语对应结构更强的情况下,迁移同样可能发生。英汉两种语言都有瞬间性动词。通过对比发现,英语瞬间性动词的标记程度更强。练习卷的完成情况表明：不同层次的英语学习者在使用瞬间性动词的过程中都不同程度地受到母语迁移的影响。

关键词：标记性标记程度瞬间性动词

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