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991.
Sarcopenia is defined as the age-related loss of skeletal muscle mass, quality, and strength. The pathophysiological mechanisms underlying sarcopenia are still not completely understood. The aim of this work was to evaluate, for the first time, the expression of NLRP3 inflammasome in bovine skeletal muscle in order to investigate the hypothesis that inflammasome activation may trigger and sustain a pro-inflammatory environment leading to sarcopenia. Samples of skeletal muscle were collected from 60 cattle belonging to three age-based groups. Morphologic, immunohistochemical and molecular analysis were performed to assess the presence of age-related pathologic changes and chronic inflammation, the expression of NLRP3 inflammasome and to determine the levels of interleukin-1β, interleukin-18 and tumor necrosis factor alpha in muscle tissue. Our results revealed the presence of morphologic sarcopenia hallmark, chronic lymphocytic inflammation and a type II fibers-selective NLRP3 expression associated to a significant decreased number of immunolabeled-fibers in aged animals. Moreover, we found a statistically significant age-related increase of pro-inflammatory cytokines such as interleukin-1β and interleukin-18 suggesting the activation of NLRP3 inflammasome. Taken together, our data suggest that NLRP3 inflammasome components may be normally expressed in skeletal muscle, but its priming and activation during aging may contribute to enhance a pro-inflammatory environment altering normal muscular anabolism and metabolism.  相似文献   
992.
In this article, modification of carbon fiber surface by carbon based nanofillers (multi-walled carbon nanotubes [CNT], carbon nanofibers, and multi-layered graphene) has been achieved by electrophoretic deposition technique to improve its interfacial bonding with epoxy matrix, with a target to improve the mechanical performance of carbon fiber reinforced polymer composites. Flexural and short beam shear properties of the composites were studied at extreme temperature conditions; in-situ cryo, room and elevated temperature (−196, 30, and 120°C respectively). Laminate reinforced with CNT grafted carbon fibers exhibited highest delamination resistance with maximum improvement in flexural strength as well as in inter-laminar shear strength (ILSS) among all the carbon fiber reinforced epoxy (CE) composites at all in-situ temperatures. CNT modified CE composite showed increment of 9% in flexural strength and 17.43% in ILSS when compared to that of unmodified CE composite at room temperature (30°C). Thermomechanical properties were investigated using dynamic mechanical analysis. Fractography was also carried out to study different modes of failure of the composites.  相似文献   
993.
Li4Ti5O12 (LTO) attracts great interest due to the “zero strain” during cycles but the poor electronic and ionic conductivity critically impede the practical application. Herein, we report a synergy strategy of tuning localized electrons to shift Fermi level and band gap by Mg/Zr co-doping and oxygen vacancy incorporation, which significantly improves Li+ and electronic transport. More importantly, the intrinsic synergistic mechanism has been revealed by neutron diffraction, X-ray absorption spectra, and first-principles calculations. The “elastic effect” of lattice induced by Mg/Zr co-doping allows LTO to accommodate more oxygen vacancies to a certain degree without a severe lattice distortion, which largely improves the electronic conductivity. Mg/Zr co-doping and oxygen vacancy incorporation effectively enhanced the dynamic characteristics of LTO electrode, achieving the excellent rate performance (90 mAh/g at 20C) and cycle stability (96.9% after 500 cycles at 10C). First-principles calculations confirm Fermi level shifts to the conduction band, and the band gap becomes narrowed due to the synergistic modulation, and the intrinsic mechanism of the enhanced electronic and Li-ion conductivity is clarified. This study offers some insights into achieving the fast Li+ insertion/extraction by tuning the crystal and electronic structure with lattice doping and oxygen vacancy engineering.  相似文献   
994.
The advent of 2D nanostructured materials as advanced fillers for polymer matrix composites has opened the doors to a plethora of new industrial applications requiring both electric and thermal management. Unique properties, in fact, can arise from accurate selection and processing of 2D fillers and their matrix. Here, we report an innovative family of nanocomposite membranes based on polyurethane (PU) and graphene nanoplatelets (GNPs), designed to improve thermal comfort in functional textiles. GNP particles were thoroughly characterized (through Raman, atomic force microscopy, high-resolution TEM, scanning electron microscope), and showed high crystallinity (ID/IG = 0.127), low thickness (D50 < 6–8 layers), and high lateral dimensions (D50 ≈ 3 μm). When GNPs were loaded (up to 10% wt/wt) into the PU matrix, their homogeneous dispersion resulted in an increase of the in-plane thermal conductivity of composite membranes up to 471%. The thermal dissipation of membranes, alone or coupled with cotton fabric, was further evaluated by means of an ad hoc system designed to simulate a human forearm. The results obtained provide a new strategy for the preparation of membranes suitable for technical textiles, with improved thermal comfort.  相似文献   
995.
汽轮机叶片金属磁记忆诊断技术   总被引:8,自引:0,他引:8  
介绍电站汽轮机叶片的金属磁记忆检测原理及应用,用磁记忆诊断技术可快速、准确检测出汽轮机叶片的裂纹和应力集中区。  相似文献   
996.
声发射源定位不确定度的计算   总被引:7,自引:1,他引:7  
姚力  赖德明 《无损检测》2002,24(11):461-463
针对声发射检测中的声发射源定位的不确定性问题,就其影响因素,在常用的16MnR钢制板件上进行了检测实验,并开展了实验数据的计算、分析与讨论。  相似文献   
997.
化学镀镍溶液光亮剂实验研究   总被引:6,自引:1,他引:6  
通过大量实验,筛选出了酸性化学镀镍液中光亮剂的最佳配方,并对加光亮剂和未加光亮剂的镀后试片进行热处理,结果表明,加光亮剂镀层的显微硬度,耐磨性、耐蚀性更优越.  相似文献   
998.
利用组合的二次回归正交实验设计方案 ,对钽低温离子渗氮条件下 ,表面物相及固溶体中氮的含量随渗氮温度、气氛总压力和氢氮摩尔比的变化进行了系统研究。发现表面渗氮层由化合物Ta6N2 .57、超晶格TaN0 .1和固溶体相组成。氮在钽中的固溶度随气压、温度和氢摩尔分数的增加而增加 ,化合物和超晶格相含量随温度增加而增加 ,同时化合物相随氢摩尔分数增加有一个极大值 ,该极大值随温度增加而下降。  相似文献   
999.
蒋业华  周荣  卢德宏  邢建东 《铸造》2002,51(1):15-17
测定控制冷却贝氏体球墨铸铁TTT曲线和磨球冷却速度及温度分布发现 :控制冷却贝氏体复相球铁TTT图存在贝氏体区 ,与珠光体区分离 ;控制冷却比浸入式水淬具有均匀的冷却速度和温度分布 ,高温阶段可避开珠光体区 ,低温阶段形成类似等温条件 ,缓慢通过贝氏体区  相似文献   
1000.
ZA27合金的半固态浆液电磁搅拌工艺及其组织和性能   总被引:6,自引:2,他引:6  
蒋业华  周荣  卢德宏  邢建东 《铸造》2002,51(2):88-91
利用自行设计的电磁搅拌装置,制备ZA27合金半固态浆料,研究了在等温搅拌制度下,温度、磁感应强度、搅拌时间对合金组织和性能的影响。结果表明:磁感应强度大、等温范围470-480℃、搅拌7.5-15min,ZA27合金的组织和性能较佳。  相似文献   
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