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排序方式: 共有447条查询结果,搜索用时 15 毫秒
1.
Maria Luisa Grilli Daniele Valerini Anca Elena Slobozeanu Bogdan O. Postolnyi Sebastian Balos Antonella Rizzo Radu Robert Piticescu 《Materials》2021,14(7)
Several applications, where extreme conditions occur, require the use of alloys often containing many critical elements. Due to the ever increasing prices of critical raw materials (CRMs) linked to their high supply risk, and because of their fundamental and large utilization in high tech products and applications, it is extremely important to find viable solutions to save CRMs usage. Apart from increasing processes’ efficiency, substitution, and recycling, one of the alternatives to preserve an alloy and increase its operating lifetime, thus saving the CRMs needed for its manufacturing, is to protect it by a suitable coating or a surface treatment. This review presents the most recent trends in coatings for application in high temperature alloys for aerospace engines. CRMs’ current and future saving scenarios in the alloys and coatings for the aerospace engine are also discussed. The overarching aim of this paper is to raise awareness on the CRMs issue related to the alloys and coating for aerospace, suggesting some mitigation measures without having the ambition nor to give a complete overview of the topic nor a turnkey solution. 相似文献
2.
[目的]应用气-液界面染毒技术探索柴油机尾气对人支气管上皮(16HBE)细胞急性毒性作用. [方法]在流速为20 mL/min,37℃的条件下,用柴油机尾气分别对生长在多孔膜上的16HBE细胞持续染毒5、10、15、20、30 min,分别使用CCK-8(Cell Counting Kit-8)检测法、乳酸脱氢酶(LDH)释放法、中性红摄入法(NRU)检测柴油机尾气对细胞存活率的影响;对细胞存活率约50%以上的染毒组用流式细胞术检测柴油机尾气对细胞凋亡率的影响;同时对每个染毒组分别设置用滤膜过滤的洁净空气作为对照组,暴露时间和检测方法均与染毒组-致. [结果]3种存活率检测方法的结果表明,染毒组与对照组相比,柴油机尾气持续染毒15 min及更长时间以后,细胞存活率降低,差异有统计学意义(P< 0.05),且呈随染毒时间延长而逐渐降低的趋势.3种方法比较表明,低流速短时间柴油机尾气对16HBE细胞的损伤作用以细胞膜损伤最为显著,其次是线粒体损伤.用柴油机尾气持续染毒10、15 min,染毒组细胞早期凋亡率、晚期凋亡及坏死率较对照组均升高,差异均有统计学意义(P< 0.05).10、15 min染毒组的晚期凋亡及坏死细胞多于早期凋亡细胞(P<0.05). [结论]气-液界面染毒技术可以应用于柴油机尾气等气溶胶有害物质的体外毒性研究;同时发现柴油机尾气导致的16HBE细胞急性毒性为细胞膜损伤、线粒体损伤及细胞凋亡. 相似文献
3.
Helen Susannah Moat Christopher Y. Olivola Nick Chater Tobias Preis 《Topics in Cognitive Science》2016,8(3):685-696
When making a decision, humans consider two types of information: information they have acquired through their prior experience of the world, and further information they gather to support the decision in question. Here, we present evidence that data from search engines such as Google can help us model both sources of information. We show that statistics from search engines on the frequency of content on the Internet can help us estimate the statistical structure of prior experience; and, specifically, we outline how such statistics can inform psychological theories concerning the valuation of human lives, or choices involving delayed outcomes. Turning to information gathering, we show that search query data might help measure human information gathering, and it may predict subsequent decisions. Such data enable us to compare information gathered across nations, where analyses suggest, for example, a greater focus on the future in countries with a higher per capita GDP. We conclude that search engine data constitute a valuable new resource for cognitive scientists, offering a fascinating new tool for understanding the human decision‐making process. 相似文献
4.
The pituitary tumor-transforming gene 1 (PTTG1), also known as Securin, is considered an oncogene. This study aimed to investigate the role of PTTG1 in clear cell renal cell carcinoma (ccRCC) using in silico bioinformatics approaches. A pan-cancer analysis using The Cancer Genome Atlas (TCGA) data indicated that among all cancer types copy number amplification of PTTG1 gene was most frequently found in ccRCC. However, amplification of PTTG1 gene copy number did not correlate with the increase of mRNA level in ccRCC, and did not predict the patients' overall survival. Instead, ccRCC was correlated with overexpression of PTTG1 mRNA, and its expression level was stage-dependent increased in cancer patients. An outlier analysis using the Oncomine database suggested that PTTG1 mRNA expression served as a good biomarker for ccRCC. Pathway analysis for upregulated genes enriched in PTTG1-high expressing ccRCC patients found that PTTG1 overexpression was associated with mitotic defects. Mining drug sensitivity data using the Cancer Therapeutics Response Portal (CTRP) discovered that PTTG1-high expressing ccRCC cell lines were susceptible to a Rac1 (Ras-related C3 botulinum toxin substrate 1) inhibitor NSC23766. Therefore, this study provides an in silico insight into the role of PTTG1 in ccRCC, and repurposes the Rac1 inhibitor NSC23766 for treating PTTG1-high expressing ccRCC. 相似文献
5.
6.
孙卫星 《中国医疗器械杂志》2013,(3):182-184
目的为了实现医学装备信息化管理,需要对本行业基础数据进行挖掘和应用.方法借助搜索引擎及在线翻译等工具,收集基础信息,并用信息抽取等方法进行数据挖掘.结果对收集信息进行计算机和人工处理后,建立满足信息化要求的专业数据库.结论基础数据在医学装备信息化中的应用,使管理更具便捷性、可操作性和规范性. 相似文献
7.
目的:比较最小化心室起搏中心室起搏管理(MVP)与房室间期自动搜索[Search AV(+)]功能对右室起搏比例(VP%)及左室射血分数(LVEF)的影响.方法:50例症状性窦缓、病态窦房结综合征、间歇性房室传导阻滞的患者,均安装双腔起搏器,分为MVP组和Search AV(+)组,程控MVP组关闭Search AV(+)功能,开启MVP功能;Search AV(+)组开启Search AV(+)功能.于术后随访,比较其6个月的心房起搏、心室起搏比例、高频心房事件次数,及LVEF的值.结果:50例患者完成随访,MVP组比Search AV(+)组的心室起搏比例、高频心房事件次数都显著降低,分别为(11.4±8.3)%,(36.7±7.4)%和(32±10)次,(86±16)次;6个月的LVEF值较术前有显著差异,两组心房起搏比例、12个月的LVEF值差异无统计学意义.结论:MVP功能与SearchAV(+)功能相比可更加减少不必要的右心室起搏,减少高频心房事件. 相似文献
8.
9.
Heather Andersen Penny MacElveen-Hoehn 《Journal of pain & palliative care pharmacotherapy》2013,27(2):37-54
Two dozen leading sites on the World Wide Web that pertain to pain management and palliative care are listed and described. Strengths and limitations are discussed. 相似文献
10.
目的了解不同级别临床医师常用医学检索软件和工具的使用情况。
方法设计调查问卷,分别对北京市某医院高年级见习医师、住院医师、主治医师、副主任/主任医师(≤45岁、>45岁各50名)各100名进行问卷调查。
结果高年级见习医师检索软件首选百度(50%)、检索工具首选手机(65%);住院医师检索软件首选临床指南(60%),检索工具首选手机(63%);主治医师检索软件首选临床指南(58%),检索工具首选手机(55%);副主任/主任医师≤45岁者检索软件首选PubMed(46%)、检索工具首选台式机(44%),而>45岁者检索软件首选百度(44%),检索工具首选台式机(72%)。
结论不同级别临床医师首选医学检索软件和工具不同,可能与年龄、教育环境、个人习惯等有关。 相似文献