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Joon‐Young Jun Sosuke Nakajima Koji Yamazaki Yuji Kawai Hajime Yasui Yasuyuki Konishi 《International Journal of Food Science & Technology》2015,50(4):871-877
Cystoseira hakodatensis is an unutilised brown algae belonging to family Sargassaceae. A crude methanol extract from the algae showed inhibitory effects on the growths of Bacillus cereus and Bacillus licheniformis. To isolate the major antimicrobial agent, a sequential active‐guided isolation procedure was applied: liquid–liquid extraction, column chromatography and bio‐autography. A marked antimicrobial agent (active α) was isolated in hydrophobic fraction and was determined to phenolics without carbohydrates and proteins by phytochemical test. Regarding the antimicrobial potential, the isolated active α showed better inhibitory effects against B. cereus and B. licheniformis at 2 and 4 times of lower concentrations (62.5 and 31.3 μg mL?1) in comparison with epigallocatechin gallate. These results showed that C. hakodatensis is a potential source of antimicrobial agent capable of preventing the growth of the two bacteria. 相似文献
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为了提升大断面球墨铸铁综合力学性能,通过复合添加微量合金元素铜、锑、锡、钼对大断面球墨铸铁进行微合金化处理,借助金相显微镜(OM)、扫描电子显微镜(SEM)及力学性能测试等手段,研究了Cu Sb Sn Mo复合微合金化大断面球墨铸铁微观组织和力学性能。结果表明,试验球墨铸铁具有良好的综合力学性能。大断面球墨铸铁中添加铜、锑、锡、钼后优化了材料的组织结构,基体组织为珠光体+少量牛眼状铁素体;试样石墨组织细小、圆整,分布均匀。同时,合金元素的复合加入使得其抗拉强度达到800 MPa以上,硬度约为280HB,伸长率达到5%以上。拉伸断口分析表明,微合金化大断面球墨铸铁断裂模式以解理断裂为主,伴有少量的塑性变形。 相似文献
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The cyclooxygenase-2 (COX-2) is a potent enzyme that converts arachidonic acid to prostaglandins (PG), including PGE2, a key mediator of inflammation and angiogenesis. Importantly, COX-2 is activated in response to inflammatory stimuli, where it is also believed to promote the development and progression of head and neck cancers (HNC). COX-2 can mediate its protumorigenic effect through various mechanisms, such as inducing cell proliferation, inhibition of apoptosis, and suppressing the host’s immune response. Furthermore, COX-2 can induce the production of vascular endothelial growth factors, hence, promoting angiogenesis. Indeed, the ability of COX-2 inhibitors to selectively restrict the proliferation of tumor cells and mediating apoptosis provides promising therapeutic targets for cancer patients. Thus, in this comprehensive review, we summarized the reported differential expression patterns of COX-2 in different stages of head and neck carcinogenesis—from potentially premalignant lesions to invasive carcinomas. Furthermore, we examined the available meta-analysis evidence for COX-2 role in the carcinogenesis of HNC. Finally, further understanding of the biological processes of COX-2 and its role in orchestrating cell proliferation, apoptosis, and angiogenesis may give therapeutically beneficial insight to develop the management plan of HNC patients and improve their clinical outcomes. 相似文献
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Differences between oculomotor and perceptual artifacts for temporally limited head mounted displays
Alexander Goettker Kevin J. MacKenzie T. Scott Murdison 《Journal of the Society for Information Display》2020,28(6):509-519
We used perceptual and oculomotor measures to understand the negative impacts of low (phantom array) and high (motion blur) duty cycles with a high‐speed, AR‐likehead‐mounted display prototype. We observed large intersubject variability for the detection of phantom array artifacts but a highly consistent and systematic effect on saccadic eye movement targeting during low duty cycle presentations. This adverse effect on saccade endpoints was also related to an increased error rate in a perceptual discrimination task, showing a direct effect of display duty cycle on the perceptual quality. For high duty cycles, the probability of detecting motion blur increased during head movements, and this effect was elevated at lower refresh rates. We did not find an impact of the temporal display characteristics on compensatory eye movements during head motion (e.g., VOR). Together, our results allow us to quantify the tradeoff of different negative spatiotemporal impacts of user movements and make subsequent recommendations for optimized temporal HMD parameters. 相似文献
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主要探讨了某石化装置蒸汽发生系统的仪表工程设计,提出了复杂控制方案、联锁方案设计,同时也详述了影响系统设计的因素,如测量补偿和迁移等。 相似文献
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研究了厚膜永磁阵列微致动器中的磁场分布,并研究了永磁阵列单元几何尺寸对微致动器电磁力的影响。结果表明,厚膜永磁阵列单元高宽比和磁体单元间隔对微致动器电磁力影响较大磁徕单元高宽比为0.7是一个比较合适的尺寸。 相似文献
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