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81.
Head and neck squamous cell carcinoma (HNSCC) tumor phenotypes and clinical outcomes are significantly influenced by etiological agents, such as HPV infection, smoking, and alcohol consumption. Accordingly, the intratumor microbiome has been increasingly implicated in cancer progression and metastasis. However, few studies characterize the intratumor microbial landscape of HNSCC with respect to these etiological agents. In this study, we aimed to investigate the bacterial and fungal landscape of HNSCC in association with HPV infection, smoking, and alcohol consumption. RNA-sequencing data were extracted from The Cancer Genome Atlas (TCGA) regarding 449 tissue samples and 44 normal samples. Pathoscope 2.0 was used to extract the microbial reads. Microbe abundance was compared to clinical variables, oncogenic signatures, and immune-associated pathways. Our results demonstrated that a similar number of dysregulated microbes was overabundant in smokers and nonsmokers, while heavy drinkers were characterized by an underabundance of dysregulated microbes. Conversely, the majority of dysregulated microbes were overabundant in HPV+ tumor samples when compared to HPV- tumor samples. Moreover, we observed that many dysregulated microbes were associated with oncogenic and metastatic pathways, suggesting their roles in influencing carcinogenesis. These microbes provide insights regarding potential mechanisms for tumor pathogenesis and progression with respect to the three etiological agents.  相似文献   
82.
Plant cell deformation is a mechanical process that is driven by differences in the osmotic pressure inside and outside of the cell and is influenced by cell wall properties. Legume leaf movements result from reversible deformation of pulvinar motor cells. Reversible cell deformation is an elastic process distinct from the irreversible cell growth of developing organs. Here, we begin with a review of the basic mathematics of cell volume changes, cell wall function, and the mechanics of bending deformation at a macro scale. Next, we summarize the findings of recent molecular genetic studies of pulvinar development. We then review the mechanisms of the adaxial/abaxial patterning because pulvinar bending deformation depends on the differences in mechanical properties and physiological responses of motor cells on the adaxial versus abaxial sides of the pulvinus. Intriguingly, pulvini simultaneously encompass morphological symmetry and functional asymmetry along the adaxial/abaxial axis. This review provides an introduction to leaf movement and reversible deformation from the perspective of mechanics and molecular genetics.  相似文献   
83.
Mast cells (MC) are a key effector cell in multiple types of immune responses, including atopic conditions. Allergic diseases have been steadily rising across the globe, creating a growing public health problem. IgE-mediated activation of MCs leads to the release of potent mediators that can have dire clinical consequences. Current therapeutic options to inhibit MC activation and degranulation are limited; thus, a better understanding of the mechanisms that regulate MC effector functions in allergic inflammation are necessary in order to develop effective treatment options with minimal side effects. Several cytokines have been identified that play multifaceted roles in regulating MC activation, including TGFβ, IL-10, and IL-33, and others that appear to serve primarily anti-inflammatory functions, including IL-35 and IL-37. Here, we review the literature examining cytokines that regulate MC-mediated allergic immune responses.  相似文献   
84.
由于镁对钢的脱氧、脱硫、净化钢水及转变夹杂物形态的良好作用,近年来许多冶金工作者致力于加镁精炼钢水的研究工作,但因在冶金温度下镁的蒸汽压很高,而其在钢水的溶解度又极小,加入困难,这方面的研究多归于失败。本文利用阿亨大学热力学数据库计算了以氩作为载气喷镁的脱氧、脱硫作用,以及压力和氩量对其影响,通过实验制定了行之有效的喷吹工艺,选择了合适的控制参数。
在1-3大压下,氩量为0.1-0.3N.L/m:n,可以向钢水成功地喷入镁。经过镁精炼的钢水,氧含量可降至4ppm,硫含量降至10ppm,氧化物及硫化物的评级均为0级,其尺寸均在5μm之下。随着喷镁量的增加(钢水重量的0.062至%0.56%),夹杂物中镁的氧化物及硫化物量增加,夹杂物总量减少且呈球形,此种夹杂物在热形变中不变形。因此在通常材料中所存在的各向异性完全消失,特别是缺口冲击韧性横向性能值提高了2~3倍。文章对材料在不同温度下的冲击韧性、过渡温度及断口夹杂物的形态进行了研究和论述。  相似文献   
85.
使用Al2O3坩埚在真空感应炉内测定了1600℃时氮在含C还原渣和钢液之间的总传质系数βo.研究表明,βo与气相中氮分压PN2的大小有关,随着PN2的增加βo增大.由物料平衡计算得出,在本实验条件下,βo为3.7×10-4 cm/S.  相似文献   
86.
Batienkov  V. T.  Batienkov  R. V. 《Metallurgist》2019,63(5-6):642-650
Metallurgist - A number of combine-harvester components are produced by mass production of hot-forged sintered powder blanks in the at “Rostsel’mash” plant. With the aim of...  相似文献   
87.
Inorganic Materials - This paper presents results of analysis of the patent, scientific, and technical literature concerned with the physicochemical and technological foundations of the preparation...  相似文献   
88.
89.
On the mechanism of aluminum ignition in steam explosions   总被引:1,自引:0,他引:1  
An available theory [Epstein, M., Fauske, H.K., 1994. A crystallization theory of underwater aluminum ignition. Nucl. Eng. Des. 146, 147–164] of the ignition of aluminum melt drops under water, which is based on the assumption that the aluminum oxide (Al2O3) drop-surface skin first appears in a metastable molten state, is compared with existing experimental data on the ignition of aluminum drops behind shock waves in water [Theofanous, T.G., Chen, X., DiPiazza, P., Epstein, M., Fauske, H.K., 1994. Ignition of aluminum droplets behind shock waves in water, Phys. Fluids 6, 3513–3515]. The predicted and measured ignition temperature of about 1770 K coincides approximately with the spontaneous nucleation temperature of supercooled liquid Al2O3 (1760 K). This suggests that the crystallization of the oxide layer represents a strong ‘barrier’ to aluminum drop ignition under water. Apparently a similar interpretation is applicable to aluminum drop ignition in gaseous oxidizing atmospheres. We conclude from the theory that the low-temperature aluminum ignitions (in the range 1100–1600 K) that have been observed during steam explosions are a consequence of the short aluminum drop oxidation times in this environment relative to the characteristic time for Al2O3 crystallization. Several aspects of the aluminum drop/shock interaction experiments besides ignition are discussed in the paper. In particular, the experiments provide strong evidence that during the course of a vapor explosion metal fragmentation occurs via a thermal mechanism at low pressure and precedes the development of a high-pressure shock.  相似文献   
90.
Hybrid Recycle System (HRS) is proposed as an advanced recycle system. The HRS consists of improved fluoride volatility reprocessing and vibration packing MOX fuel fabrication processing. For the former, a part of U is volatilized as hexafluoride with diluted F2 gas, and then residual U and Pu are volatilized with concentrated F2 gas. Plutonium content of the mixed fluoride gas can be adjusted as desired by controlling the U fluorination reaction in the first step. The U is highly decontaminated and the mixture gas of UF6 and PuF6 is not purified. The fluoride mixture is reacted with H2O and H2 and directly converted to the mixed oxide grain for the vibration packing. The HRS can reduce the costs of reprocessing and fuel fabrication, the amounts of radioactive wastes and the probability of Pu proliferation.  相似文献   
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