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31.
Britta Marko Paulina Heurich Patrick Thon Frieda Zimmer Lars Bergmann Hartmuth Nowak Katharina Rump Bjrn Koos Michael Adamzik Matthias Unterberg Tim Rahmel 《International journal of molecular sciences》2022,23(14)
The functionally important NF-κB1 promoter polymorphism (−94ins/delATTG) significantly shapes inflammation and impacts the outcome of sepsis. However, exploratory studies elucidating the molecular link of this genotype-dependent pattern are lacking. Accordingly, we analyzed lipopolysaccharide-stimulated peripheral blood mononuclear cells from both healthy volunteers (n = 20) and septic patients (n = 10). All individuals were genotyped for the −94ins/delATTG NF-κB1 promoter polymorphism. We found a diminished nuclear activity of the NF-κB subunit p50 in ID/DD genotypes after 48 h of lipopolysaccharide stimulation compared to II genotypes (p = 0.025). This was associated with higher TNF-α (p = 0.005) and interleukin 6 concentrations (p = 0.014) and an increased production of mitochondrial radical oxygen species in ID/DD genotypes (p = 0.001). Although ID/DD genotypes showed enhanced activation of mitochondrial biogenesis, they still had a significantly diminished cellular ATP content (p = 0.046) and lower mtDNA copy numbers (p = 0.010) compared to II genotypes. Strikingly, these findings were mirrored in peripheral blood mononuclear cells taken from septic patients. Our results emphasize the crucial aspect of considering NF-κB subunits in sepsis. We showed here that the deletion allele of the NF-κB1 (−94ins/delATTG) polymorphism was associated with the lower nuclear activity of subunit p50, which, in turn, was associated with aggravated inflammation and mitochondrial dysfunction. 相似文献
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33.
青西凹陷窟窿山构造青2-50井钻井液技术 总被引:1,自引:0,他引:1
青2-50井地层十分复杂,如泥页岩易发生水化坍塌,硬脆性页岩易垮,层理裂缝发育,易漏,地层倾角大,井眼应力不均衡等,因此为保证井壁稳定,需把钻井液配方的优选和适时有效地转化作为钻井施工的重点.在柳沟庄组以上地层,采用了加生石灰的阳离子钻井液,通过保持较高矿化度,满足了地层和工程的需要.在钻至深部地层以后,转化为阳离子聚磺钻井液,提高了原体系的抗温能力,并解决了深井阶段的裂隙封堵、地层垮塌、润滑防卡和油层保护等难题.青2-50井的顺利完钻为提高该区块的钻探开发速度积累了经验,并建议选用复合金属离子(或两性离子)聚合物(防塌)钻井液替代阳离子钻井液. 相似文献
34.
Shuohong Gao Xingchen Yan Cheng Chang Xinliang Xie Qingkun Chu Zhaoyang Deng Bingwen Lu Min Liu Hanlin Liao Nouredine Fenineche 《金属学报(英文版)》2022,35(9):1439-1452
This work focuses on the structure and magnetic properties of Fe-50wt% Ni permalloy manufactured from the pre-alloyed powder by selective laser melting (SLM). The selective laser melted (SLMed) alloys were characterized by a 3D profilometer,optical microscope, scanning electron microscope, X-ray diffraction, etc. The effects of the volume energy density of laser(LVED) on structure, and magnetic properties with coercivity ( H c ), remanence ( B r ), and power losses ( P 相似文献
35.
In this paper, the reason of 50Mn2V transverse cracking is studied by optical metallographic, SEM and in situ analysis system. Results show that the pearlite is surrounded by the net‐like pro‐eutectoid ferrite which locates at the former austenite grain boundary, the hydrogen content (ca.2 × 10?4 wt%) exceeds the critical solubility in room temperature structure, divers types, and sizes inclusions (10–100 µm), plenty of fissures (2–50 µm) and classical cleavage fracture surface are obviously observed, meanwhile, a great degree of elements segregation (P, S, V, Ni, Cr correspond to 1.757, 1.674, 1.729, 1.475, 1.195, respectively) and a poorly 0.9283 integral density exist in this blank. From the above, internal gas pressure should be the dominant factor that leads the transverse embrittlement, while internal stresses, element segregation, and defects play an ancillary role. 相似文献
36.
简要介绍长钢轧钢厂ER50—6热轧盘条的试生产情况。通过采取控制化学成分、开轧温度、吐丝温度及风冷相变等措施。不断完善生产工艺,使盘条的各项性能达到了标准要求,从而满足了用户要求。 相似文献
37.
As a practical solution to reduce the emission pollution and energy crisis, the research and development of HICE has been processed in several decades. The focus of this paper is trying to explore the new features of the combustion duration in HICE not only by engine experiment, but also by analysis of the physical properties of hydrogen, especially the obvious difference from that of gasoline. Firstly, the laminar flame speed difference between hydrogen and gasoline was studied and discussed. Secondly, a distinctive rule of combustion duration in HICE was discovered by analyzing the experiment data. Finally, as a key reference point to the HICE operation, a new characteristic of the location of 50% mixture combust up was proposed and analyzed, this will be helpful for the calibration of optimum ignition timing. 相似文献
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39.
Al?high Si alloys were designed by the addition of Cu or Mg alloying elements to improve the mechanical properties. It is found that the addition of 1 wt.% Cu or 1 wt.% Mg as strengthening elements significantly improves the tensile strength by 27.2% and 24.5%, respectively. This phenomenon is attributed to the formation of uniformly dispersed fine particles (Al2Cu and Mg2Si secondary phases) in the Al matrix during hot press sintering of the rapidly solidified (gas atomization) powder. The thermal conductivity of the Al?50Si alloys is reduced with the addition of Cu or Mg, by only 7.3% and 6.8%, respectively. Therefore, the strength of the Al?50Si alloys is enhanced while maintaining their excellent thermo-physical properties by adding 1% Cu(Mg). 相似文献
40.
This article develops an improved seismic risk assessment formulation exhibiting both random and bounded uncertainties using a probability and parallelepiped convex set mixed model. Limit thresholds for different types of components are described via a probabilistic model. The distribution parameters of limit thresholds are originally treated by employing a multidimensional parallelepiped convex model, in which marginal intervals are utilised to represent scattering levels for the distribution parameters, while relevant angle are employed to express the correlation between uncertain distribution parameters. The structural responses, i.e., engineering demand parameters (EDPs), are considered as correlated random variables and are assumed to follow a multidimensional lognormal distribution. A performance limit state function, which allows considering the relationship between the EDPs and the corresponding limit thresholds, is employed to reflect the coexistence of both random and parallelepiped convex variables. The limit state function is mapped into the standard parameter space via a transformation technique. Then, the improved seismic risk formulation, characterised through a probability and parallelepiped convex mixed variables, can be derived with the combination of the seismic fragility function and the ground motion hazard curve. The main purpose is to illustrate that the performance limit states should be properly modeled as random and parallelepiped convex mixed variables rather than only random or deterministic quantities. A six-story reinforced concrete building designed according to Chinese codes are used to illustrate the proposed approach for constructing hazard curves. The interstory drift and the peak floor acceleration are the selected EDPs, calculated through incremental dynamic analysis. The results demonstrate that the calculated failure probabilities for different limit states in 50?years are found capable of meeting the requirements of Chinese seismic norms after the proposed seismic risk formulation is adopted. 相似文献