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81.
本文论述了西门子6RA70装置在双边剪夹送辊传动系统中的应用,解决了夹送辊不同步而出现的钢板走偏问题。 相似文献
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Microstructural changes in the surface layer of Ti-6Al-4V alloy after sliding wear in vacuum have been studied by means of scanning and transmission electron microscopy (SEM and TEM). The wear rates of Ti-6Al-4V alloy in vacuum were measured under different sliding velocities and loads. The experimental results showed that a severely deformed layer with a grain size of 50–100 nm and thickness about 70 μm was formed underneath the worn surface. Under the slower sliding velocities, the substructure of the layer had a high dislocation density, while under higher sliding velocities, twins were found to exist in the substructure. A process by which the deformed layer formed has been proposed and the deformation of materials at the contacting spots of the Ti-6Al-4V sample is discussed. 相似文献
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针对Wi-Fi 6、Wi-Fi 6E(5 GHz、6 GHz)的低功耗、宽带宽等无线局域网(WLAN)设备需求,基于65 nm CMOS工艺设计了一款两级低功耗宽带低噪声放大器(LNA)。电路第一级采用结合互补共源电路的共源共栅结构,通过电感峰化技术和负反馈技术的运用,提高输入跨导,降低噪声,并拓展带宽和提高增益平坦度。第二级在共漏极缓冲器基础上引入辅助放大结构、电感峰化技术,实现抵消第一级共源管的噪声并拓展带宽。电路采用提出的前向衬底自偏置技术,以降低电路对电源电压的依赖,整体电路实现两路电流复用,从而有效降低了功耗。仿真结果表明,在5~9.3 GHz频带内LNA的S21为17.8±0.1 dB,S11小于-9 dB、S22小于-11.9 dB,噪声系数小于1.34 dB。在0.8 V电压下整体电路功耗为5.3 mW。 相似文献
87.
Lukas Babylon Fabian Schmitt Yannik Franke Tim Hubert Gunter P. Eckert 《International journal of molecular sciences》2022,23(15)
Increased amyloid beta (Aβ) levels and mitochondrial dysfunction (MD) in the human brain characterize Alzheimer disease (AD). Folic acid, magnesium and vitamin B6 are essential micro-nutrients that may provide neuroprotection. Bioenergetic parameters and amyloid precursor protein (APP) processing products were investigated in vitro in human neuroblastoma SH-SY5Y-APP695 cells, expressing neuronal APP, and in vivo, in the invertebrate Caenorhabditis elegans (CL2006 & GMC101) expressing muscular APP. Model organisms were incubated with either folic acid and magnesium-orotate (ID63) or folic acid, magnesium-orotate and vitamin B6 (ID64) in different concentrations. ID63 and ID64 reduced Aβ, soluble alpha APP (sAPPα), and lactate levels in SH-SY5Y-APP695 cells. The latter might be explained by enhanced expression of lactate dehydrogenase (LDHA). Micronutrient combinations had no effects on mitochondrial parameters in SH-SY5Y-APP695 cells. ID64 showed a significant life-prolonging effect in C. elegans CL2006. Incubation of GMC101 with ID63 significantly lowered Aβ aggregation. Both combinations significantly reduced paralysis and thus improved the phenotype in GMC101. Thus, the combinations of the tested biofactors are effective in pre-clinical models of AD by interfering with Aβ related pathways and glycolysis. 相似文献
88.
Olivera Mitrovi Ajti Tijana Suboti
ki Milo Dikli Dragoslava iki Milica Vukoti Teodora Dragojevi Emilija
ivkovi Darko Anti Vladan oki 《International journal of molecular sciences》2022,23(13)
The calcium-binding proteins S100A4, S100A8, and S100A9 are upregulated in chronic lymphocytic leukemia (CLL), while the S100A9 promotes NF-κB activity during disease progression. The S100-protein family has been involved in several malignancies as mediators of inflammation and proliferation. The hypothesis of our study is that S100A proteins are mediators in signaling pathways associated with inflammation-induced proliferation, such as NF-κB, PI3K/AKT, and JAK/STAT. The mononuclear cells (MNCs) of CLL were treated with proinflammatory IL-6, anti-inflammatory IL-10 cytokines, inhibitors of JAK1/2, NF-κB, and PI3K signaling pathways, to evaluate S100A4, S100A8, S100A9, and S100A12 expression as well as NF-κB activation by qRT-PCR, immunocytochemistry, and immunoblotting. The quantity of S100A4, S100A8, and S100A9 positive cells (p < 0.05) and their protein expression (p < 0.01) were significantly decreased in MNCs of CLL patients compared to healthy controls. The S100A levels were generally increased in CD19+ cells compared to MNCs of CLL. The S100A4 gene expression was significantly stimulated (p < 0.05) by the inhibition of the PI3K/AKT signaling pathway in MNCs. IL-6 stimulated S100A4 and S100A8 protein expression, prevented by the NF-κB and JAK1/2 inhibitors. In contrast, IL-10 reduced S100A8, S100A9, and S100A12 protein expressions in MNCs of CLL. Moreover, IL-10 inhibited activation of NF-κB signaling (4-fold, p < 0.05). In conclusion, inflammation stimulated the S100A protein expression mediated via the proliferation-related signaling and balanced by the cytokines in CLL. 相似文献
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为了研究12C6 子辐照昆明小鼠全脑对其空间记忆的影响,采用0、0.5、1和2Gy的12C6 子束辐照昆明小鼠全脑,用八臂迷宫测试小鼠在迷宫中的觅食速度,以及其空间记忆的变化.结果发现,辐照使小鼠的觅食速度降低,但随着训练次数的增加,受辐照组与对照组的觅食速度都提高,到训练第17天,辐照组与对照组觅食能力基本相同;辐照使小鼠的空间记忆能力短期下降,但随着时间的增加,辐照组小鼠的空间记忆能力恢复到了对照水平.以上结果提示,在0~2Gy的碳离子辐照的剂量水平,辐照在短期内影响小鼠的记忆,在一定时间后,这种影响得到恢复. 相似文献