检索结果-南通市图书馆

Revealing the interlaminar shear failure behavior of unidirectional laminate under combined compression-shear loads

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2023年第26期157卷 110-119页

作者： Yueran Zhao Jian Zang Ben Jia Junchao Yang xiaopeng wan Wenzhi wang Xiangming Chen School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aircraft Strength Research Institute of China Xi’an 710065China

Due to the coupling effects between stresses in different directions,the mechanical behavior of an ad-vanced composite material under multiaxial loading is extremely complex.In this study,the influence of through-thickness compressive stress on the interlaminar shear performance of a carbon fiber-reinforced composite was experimentally investigated.Hollow cylindrical unidirectional laminate specimens were fabricated to conduct combined compression-shear tests,and the fracture morphologies of the specimens were characterized to reveal their failure behavior.The results indicate that a moderate compression load significantly enhanced the shear properties of the laminate by inhibiting crack propagation and improv-ing the friction effect.The shear strength and modulus of a laminate specimen subjected to combined stresses improved up to a maximum of 76%and 231%,respectively,over those of an equivalent specimen subjected to pure shear.However,as the applied through-thickness load approached the compressive strength of the laminate,the specimen shear capacity began to decline owing to the transition of frac-ture mechanisms.Indeed,the specimens exhibited mixed failure modes corresponding to the different stress states,which were induced by the combined effects of through-thickness compressive and shear stresses.As the applied through-thickness compressive stress increased,the dominant failure mode of the laminate specimen changed from fiber-matrix debonding to fiber shearing and then to fiber break-age,resulting in various shear performances.

关键词： Fiber-reinforced composites Mechanical behavior Multiaxial loading Failure analysis

H7N9 virus infection triggers lethal cytokine storm by activating gasdermin E-mediated pyroptosis of lung alveolar epithelial cells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2022年第1期9卷 47-55页

作者： xiaopeng wan Jiqing Li Yupeng wang Xiaofei Yu Xijun He Jianzhong Shi Guohua Deng Xianying Zeng Guobin Tian Yanbing Li Yongping Jiang Yuntao Guan Chengjun Li Feng Shao Hualan Chen State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research Institute Chinese Academy of Agricultural Sciences National Institute of Biological Sciences

The H7 N9 influenza virus emerged in China in 2013,causing more than 1560 human infections,39% of which were fatal.A ’cytokine storm’ in the lungs of H7 N9 patients has been linked to a poor prognosis and death;however,the underlying mechanism that triggers the cytokine storm is unknown.Here,we found that efficient replication of the H7 N9 virus in mouse lungs activates gasdermin E(GSDME)-mediated pyroptosis in alveolar epithelial cells,and that the released cytosolic contents then trigger a cytokine storm.Knockout of Gsdme switched the manner of death of A549 and human primary alveolar epithelial cells from pyroptosis to apoptosis upon H7 N9 virus infection,and Gsdme knockout mice survived H7 N9 virus lethal infection.Our findings reveal that GSDME activation is a key and unique mechanism for the pulmonary cytokine storm and lethal outcome of H7 N9 virus infection and thus opens a new door for the development of antivirals against the H7 N9 virus.

关键词： H7N9 virus cytokine storm gasdermin E pyroptosis

Study of thermo-fluidic characteristics for geometric-anisotropy Kagome truss-cored lattice

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2019年第7期32卷 1635-1645页

作者： Chi HOU Guangmeng YANG xiaopeng wan Jie CHEN School of Aeronautics Northwestern Polytechnical University

The aim of this paper is to provide a comprehensive comparison of the thermal insulation and heat transfer performance for Kagome truss-cored lattice along two perpendicular orientations OA and OB. Three test conditions are conducted under forced air convection for the titanium sandwich panel fabricated by 3 D printing technology. The thermo-fluidic characteristics are further explored by numerical simulation to reveal the underlying mechanisms of heat transfer enhancement.The results indicate that the orientation OB exhibits better thermal insulation than orientation OA under the identical temperature loading, while the latter outperforms the former by up to 20% higher overall heat transfer performance. In particular, the endwalls and lattice core in orientation OA achieve 9.7% and 22.5% higher area-averaged Nusselt number respectively than that in orientation OB for a given Reynolds number. The heat transfer superiority of orientation OA comes from the unique topology which induces the large scale spiral primary flows, facilitating the heat exchange between the cooling air and the surfaces of sandwich panel. However, the complex flow mixing leads to a maximum of 20% higher friction factor in orientation OA than that in orientation OB.

关键词： Forced convection Heat transfer Kagome Pressure drop Topology direction

Opposite effects of miR-155 in the initial and later stages of lipopolysaccharide(LPS)-induced inflammatory response

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2021年第7期22卷 590-598页

作者： Yuhua LIU xiaopeng wan Yuan YUAN Jingjing HUANG Yijia JIANG Kaiyue ZHAO Yan wanG Yang LIU Qingqing wanG Hongchuan JIN Laboratory of Cancer Biology Key Lab of Biotherapy in ZhejiangSir Run Run Shaw HospitalMedical School of Zhejiang UniversityHangzhou 310016China Department of Clinical Laboratory the Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310015China Institute of Immunology Zhejiang University School of MedicineHangzhou 310058China Department of Radiology the Affiliated Hospital of Hangzhou Normal UniversityHangzhou 310015China

Although microRNA-155(miR-155)is considered a pro-inflammatory mediator,cumulative evidence indicates that it also has anti-inflammatory effects in macrophages and dendritic cells.In this study,we identified the dramatic expression changes of more than half of potential miR-155-targeted genes upon lipopolysaccharide(LPS)stimulation;223 genes were down-regulated and 85 genes were up-regulated,including suppressor of cytokine signaling 1(SOCS1)and transforming growth factor-β-activated kinase 1-binding protein 2(TAB2),two well-known genes involved in miR-155-mediated regulation of the Toll-like receptor 4(TLR4)signaling pathway.We also found that miR-155 acted as an anti-inflammatory mediator in the initial stage of LPS-induced inflammatory response mainly through repressing TAB2 protein translation,and as a proinflammatory mediator by down-regulating SOCS1 in the later stage.Meanwhile,overexpression of TAB23'untranslated region(UTR)in macrophages promoted the development of endotoxin tolerance by competing for binding with miR-155,which resulted in an elevated expression level of SOCS1 protein.These findings provide new insights for understanding the regulatory mechanisms in fine-tuning of LPS-induced innate immune response.

关键词： Toll-like receptor 4(TLR4) Endotoxin tolerance MicroRNA-155(miR-155) Suppressor of cytokine signaling 1(SOCS1) Transforming growth factor-β-activated kinase 1-binding protein 2(TAB2)

基于玻璃化转变的稻谷干燥变温控制系统设计与试验

在线全文

学校读者我要写书评

暂无评论

农业工程学报 2024年第6期40卷 29-39页

作者：车刚杨潇鹏王洪超万霖董永忠陈正发潘衡黑龙江八一农垦大学工程学院大庆163319 黑龙江省农机智能装备重点实验室大庆163319 黑龙江省北大荒米业集团有限公司哈尔滨150090

针对稻谷在变温干燥过程中变温节点不明确、温度波动范围大和响应时间慢等问题,该研究设计了一种基于玻璃化转变的稻谷变温干燥控制系统。根据稻谷玻璃化转变曲线,确定变温控制策略,运用Logistic回归分析建立混配阀门开度和稻谷温度之... 详细信息

针对稻谷在变温干燥过程中变温节点不明确、温度波动范围大和响应时间慢等问题,该研究设计了一种基于玻璃化转变的稻谷变温干燥控制系统。根据稻谷玻璃化转变曲线,确定变温控制策略,运用Logistic回归分析建立混配阀门开度和稻谷温度之间的控制模型并通过最小二乘法辨识模型参数。利用遗传算法对模糊隶属度函数进行优化,目标函数值迭代至0.118收敛,寻得最优幅宽。在Simulink仿真试验中,稻谷温度设定为42℃时,模糊PID控制的响应时间为66.43 s,且超调量为3.600%,优化后的模糊PID控制响应时间为37.06 s,且超调量为0.120%;在150 s加入5 s的外部信号干扰,优化后的模糊PID控制比模糊PID控制的调节时间少4.19 s且超调量减小0.050%;在稳态时输入升温信号,优化后的模糊PID控制比模糊PID控制的调节时间少16.79 s且超调量低0.338%。利用自主研制的干燥试验台进行变温试验,在变温响应试验中,优化后的模糊PID控制比模糊PID控制在目标温度和梯度升温调节时间中分别缩短了37.56 s和18.63 s;在温度稳定性试验中,稻谷温度变化范围为41.9~42.1℃,平均相对误差小于0.4%,变异系数小于0.5%;在建三江国家农业高新技术示范区浓江农场进行生产性验证,优化后的模糊PID控制系统响应时间小于30 s,稳态温度误差在±0.15℃,平均相对误差小于0.5%。测试数据表明变温干燥控制系统性能稳定,满足实际干燥作业的生产工艺需求。

关键词：设计试验玻璃化转变稻谷变温干燥模糊PID控制

TRIM35 mediates protection against influenza infection by activating TRAF3 and degrading viral PB2

在线全文

学校读者我要写书评

暂无评论

Protein & Cell 2020年第12期11卷 894-914页

作者： Nan Sun Li Jiang Miaomiao Ye Yihan wang Guangwen wang xiaopeng wan Yuhui Zhao Xia Wen Libin Liang Shujie Ma Liling Liu Zhigao Bu Hualan Chen Chengjun Li State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069China

Tripartite motif(TRIM)family proteins are important effectors of innate immunity against viral infections.Here we identified TRIM35 as a regulator of TRAF3 activation.Deficiency in or inhibition of TRIM35 suppressed the production of type I interferon(IFN)in response to viral infection.777m35-deficient mice were more susceptible to influenza A virus(IAV)infection than were wild-type mice.TRIM35 promoted the RIG-Imediated signaling by catalyzing Lys63-linked polyubiquitination of TRAF3 and the subsequent formation of a signaling complex with VISA and TBK1.IAV PB2 polymerase countered the innate antiviral immune response by impeding the Lys63-linked polyubiquitination and activation of TRAF3.TRIM35 mediated Lys48-linked polyubiquitination and proteasomal degradation of IAV PB2,thereby antagonizing its suppression of TRAF3 activation.Our in vitro and in vivo findings thus reveal novel roles of TRIM35,through catalyzing Lys63-or Lys48-linked polyubiquitination,in RIG-I antiviral immunity and mechanism of defense against IAV infection.

关键词： influenza A virus PB2 TRIM35 TRAF3 ubiquitination antiviral immunity

基于健康信念模型的北京市某三级甲等医院孕妇口腔卫生保健行为及影响因素的分析

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中华预防医学杂志 2024年第3期58卷 331-336页

作者：张志媛郑丹萍王茜谢嫣王欣欣万阔付晨薇霍晓鹏中国医学科学院北京协和医学院、北京协和医院国际医疗部北京100730 中国医学科学院北京协和医学院、北京协和医院口腔科北京100730 中国医学科学院北京协和医学院、北京协和医院妇产科北京100730 中国医学科学院北京协和医学院、北京协和医院护理部北京100730

目的:基于健康信念模型分析孕妇口腔卫生保健行为的影响因素。方法:采用横断面调查的方法,于2022年7至12月在北京协和医院驻点,对到院做产前检查的316名孕妇应用孕妇口腔卫生保健行为的健康信念问卷及自我效能量表进行调查。采用 t检验... 详细信息

目的:基于健康信念模型分析孕妇口腔卫生保健行为的影响因素。方法:采用横断面调查的方法,于2022年7至12月在北京协和医院驻点,对到院做产前检查的316名孕妇应用孕妇口腔卫生保健行为的健康信念问卷及自我效能量表进行调查。采用 t检验和 χ^(2)检验分析健康信念、自我效能等社会心理学因素对口腔保健行为的影响。结果:纳入孕妇316名中,110(34.8%)名孕妇日常口腔保健行为不佳,120(38.1%)名的孕妇在孕前或孕期未行口腔检查。孕妇整体口腔保健的健康信念不高,得分为6.63+3.23、中位得分为7(5)。感知口腔疾病的易感性( OR=1.51,95% CI:1.026~2.213)、日常生活的自我效能( OR=2.64,95% CI:1.384~5.040)、口腔检查的自我效能( OR=1.74,95% CI:1.184~2.570)是孕妇日常口腔卫生保健行为的独立影响因素。健康动力( OR=2.47,95% CI:1.474~4.126)及口腔检查的自我效能( OR=4.17,95% CI:2.626~6.619)是孕妇孕前及孕期口腔检查行为的独立影响因素。结论:孕妇口腔保健的健康信念特别是感知易感性、健康动力及自我效能与孕妇口腔卫生保健行为密切相关。切实提升孕妇口腔保健的健康信念及自我效能,避免潜在障碍,利于有效地推进孕妇口腔保健工作。

关键词：孕妇健康信念模型口腔卫生自我效能

考虑界面摩擦效应的齿轮齿面断裂风险预测研究

在线全文

学校读者我要写书评

暂无评论

机械强度 2024年第3期46卷 743-749页

作者：职彦锋王晓鹏曹志刚管洪杰余飞鹏范瑞丽李海霞万少雄郑州机械研究所有限公司郑州450001 郑州航空工业管理学院郑州450015

在循环载荷作用下,齿轮齿面断裂是裂纹源萌生于次表层位置发生的一种疲劳断裂失效形式,该失效模式与轮齿内部位置点的局部材料强度和局部应力状态密切相关。基于接触理论及弹性力学基础理论,建立含界面摩擦的轮齿内场应力和含硬度梯度... 详细信息

在循环载荷作用下,齿轮齿面断裂是裂纹源萌生于次表层位置发生的一种疲劳断裂失效形式,该失效模式与轮齿内部位置点的局部材料强度和局部应力状态密切相关。基于接触理论及弹性力学基础理论,建立含界面摩擦的轮齿内场应力和含硬度梯度的应力强度计算数学模型,开展齿轮齿面断裂风险预测研究。结果表明,计算最大应力风险位置发生在齿面下一定深度位置,与齿面断裂疲劳源表征位置基本一致。随着摩擦因数的增加,轮齿内部安全系数降低,表明界面润滑不良易引起轮齿内部裂纹加速萌生而造成齿面断裂疲劳失效。提出的齿面断裂风险预测模型为抗齿轮齿面断裂设计制造提供基础技术性保障和支撑。

关键词：齿轮齿面断裂摩擦效应风险分析

维普期刊数据库博看期刊

“就地取材”的小木桥修补制作教学实践环节设计

在线全文

学校读者我要写书评

暂无评论

创新创业理论研究与实践 2024年第3期7卷 145-148页

作者：张永杰万小朋王海涛西北工业大学民航学院陕西西安710072

为提升航空专业本科生的动手实践和综合分析能力,该文设计了“就地取材”的小木桥修补制作教学实践环节,提出了具体实施步骤,并制定了面向制作过程的全流程考核方法和评价标准,形成了完整的“知行合一”实践教学实施方案和考核体系,达... 详细信息

为提升航空专业本科生的动手实践和综合分析能力,该文设计了“就地取材”的小木桥修补制作教学实践环节,提出了具体实施步骤,并制定了面向制作过程的全流程考核方法和评价标准,形成了完整的“知行合一”实践教学实施方案和考核体系,达到了“知行并进”的实践教学效果,能够为提升航空专业实践教学水平提供范例。

关键词：航空专业实践教学 “就地取材” 动手制作实践考核方法知行合一