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51.
尾水管高度和宽度对水轮机水力性能的影响 总被引:2,自引:0,他引:2
针对不同高度和宽度的尾水管,通过分析其内部水流的流动情况,论述了高度和宽度对尾水管设计的重要性,同时采用CFD分析和模型试验的方法来确定尾水管高度和宽度对水轮机水力性能的影响。 相似文献
52.
The purpose of this study was to demonstrate the presence of vinculin and alpha2 integrin in chondrocytes in situ and epithelial cells. We also determined that the appropriate fixation and extraction protocols for immunohistochemistry and laser scanning confocal microscopy for an integral membrane protein and an actin-associated protein in cultured cells and whole tissue was different. Cultured epithelial cells, whole mount human cornea and avian cartilage were fixed and prepared using a number of standard procedures used for indirect fluorescence immunohistochemistry. The distribution of vinculin was cell-type and fixation-specific. Chondrocytes and cultured epithelial cells demonstrated vinculin in areas that appear to be associated with filamentous actin. Vinculin was associated with cell membranes in human cornea. The expression of alpha2 integrin observed in chondrocytes fixed with methanol, paraformaldehyde, or formaldehyde is consistent with its role in cell-substrate interaction, but may also suggest a role in dividing and differentiating cells. The localization of alpha2 integrin in human corneal epithelia supports its role as a cell-cell adhesion molecule. The cytoplasmic distribution of vinculin and alpha2 integrin in tissues fixed without detergent extraction suggests that the fixation step may be sufficient for antibody penetration and antigen extraction. These studies are the first report of vinculin and alpha2 integrin in embryonic chondrocytes. In addition we have shown that confocal laser scanning microscopy combined with proper fixation and extraction protocols may optimize the localization of antigens in cultured and whole mount cells. 相似文献
53.
为了给重离子治癌装置的照射野均匀度的确定提供依据,从理论上研究了重离子照射野均匀度对细胞存活率的影响,以细胞存活率曲线的线性平方模型为基础,导出了受不均匀重离子照射野照射时的细胞存活率与剂量的关系式,利用这个关系式讨论了照射野均匀度对细胞存活率的影响,结果表明,受不均匀照射野照射时的细胞存活率要比受理想的均匀照射野照时的细胞存活率大,均匀度越差细胞存活率越大;当实际照射野均匀度>95%时,方可将实际的照射野作为理想的均匀照射野来处理,因此,重离子治癌装置的照射野均匀度应>95%,同时指出,在对不同的实验室所得到的细胞存活率曲线进行比较时,应考虑不同的实验室的重离子照射野的均匀度的一致性。 相似文献
54.
55.
本文以连通片检测器无性模板的设计为例,给出了细胞神经网络中无性模板的设计方法及连通片检测器无性模板中各元素的数值范围。 相似文献
56.
鉴于多数断裂韧度JIC试验无法按GB/T2038—1991测出结果,对JIC试验方案进行了分析,探讨了在JIC测试中存在的问题并应用GB/T2038—1991和GB/T2038—1980进行了相应的试验。结果表明,按照GB/T2038—1991标准试验的可行性与材料的有效屈服强度有关;采用GB/T2038—1991标准测出的JIC值一般比旧标准偏大;GB/T2038—1991已经不能适应材料发展的需要,迫切需要修订和完善。 相似文献
57.
58.
Runnan Yu Huifeng Yao Zhenyu Chen Jingmin Xin Ling Hong Ye Xu Yunfei Zu Wei Ma Jianhui Hou 《Advanced materials (Deerfield Beach, Fla.)》2019,31(18)
Fine‐tuning of the nanoscale morphologies of the active layers in polymer solar cells (PSCs) through various techniques plays a vital role in improving the photovoltaic performance. However, for emerging nonfullerene (NF) PSCs, the morphology optimization of the active‐layer films empirically follows the methods originally developed in fullerene‐based blends and lacks systematic studies. In this work, two solid additives with different volatilities, SA‐4 and SA‐7, are applied to investigate their influence on the morphologies and photovoltaic performances of NF‐PSCs. Although both solid additives effectively promote the molecular packing of the NF acceptors, due to the higher volatility of SA‐4, the devices processed with SA‐4 exhibit a power conversion efficiency of 13.5%, higher than that of the control devices, and the devices processed with SA‐7 exhibit poor performances. Through a series of detailed morphological analyses, it is found that the volatilization of SA‐4 after thermal annealing is beneficial for the self‐assembly packing of acceptors, while the residuals due to the incomplete volatilization of SA‐7 have a negative effect on the film morphology. The results delineate the feasibility of applying volatilizable solid additives and provide deeper insights into the working mechanism, establishing guidelines for further material design of solid additives. 相似文献
59.
Chen-Yuan Kao Jinlin Jiang Will Thompson Eleftherios T. Papoutsakis 《International journal of molecular sciences》2022,23(10)
Megakaryocytes release submicron size microparticles (MkMPs) in circulation. We have shown that MkMPs target CD34+ hematopoietic stem/progenitor cells (HSPCs) to induce megakaryocytic differentiation, and that small RNAs in MkMPs play an important role in the development of this phenotype. Here, using single-molecule real-time (SMRT) RNA sequencing (RNAseq), we identify the synergetic effect of two microRNAs (miRs), miR-486-5p and miR-22-3p (highly enriched in MkMPs), in driving the Mk differentiation of HSPCs in the absence of thrombopoietin (TPO). Separately, our data suggest that the MkMP-induced Mk differentiation of HSPCs is enabled through JNK and PI3K/Akt/mTOR signaling. The interaction between the two signaling pathways is likely mediated by a direct target of miR-486-5p and a negative regulator of PI3K/Akt signaling, the phosphatase and tensin homologue (PTEN) protein. Our data provide a possible mechanistic explanation of the biological effect of MkMPs in inducing megakaryocytic differentiation of HSPCs, a phenotype of potential physiological significance in stress megakaryopoiesis. 相似文献
60.
Mariana P. Pinho Guilherme A. Lepski Roberta Rehder Nadia E. Chauca-Torres Gabriela C. M. Evangelista Sarah F. Teixeira Elizabeth A. Flatow Jaqueline V. de Oliveira Carla S. Fogolin Nataly Peres Analía Arvalo Venncio Alves Jos A. M. Barbuto Patricia C. Bergami-Santos 《International journal of molecular sciences》2022,23(10)
Immunotherapy has brought hope to the fight against glioblastoma, but its efficacy remains unclear. We present the case of CST, a 25-year-old female patient with a large right-hemisphere glioblastoma treated with a dendritic–tumor cell fusion vaccine. CST showed a near-complete tumor response, with a marked improvement in her functional status and simultaneous increases in tumor-specific CD8+ and CD4+ T cells. Two months before recurrence, the frequency of tumor-specific T cells decreased, while that of IL-17 and CD4+ T cells increased. CST passed away 15 months after enrollment. In this illustrative case, the tumor-specific CD4+ T-cell numbers and phenotype behaved as treatment efficacy biomarkers, highlighting the key role of the latter in glioblastoma immunotherapy. 相似文献