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1.
This paper investigates the quantized sliding mode control of Markov jump systems with time‐varying delay. A dynamical adjustment law is explored to quantize the system output. By constructing an observer‐based integral sliding surface, a sliding mode controller is designed to take over the dynamical motion of state estimation and ensure the reachability of sliding surface. A new scaling manner is developed to build the bound between the system output and quantized error. With the help of separation strategies for controller synthesis and general transition probabilities and a lower bound theorem for nonlinear integral terms, a new synthesis method to ensure the required stability and meet the required performance is proposed in the form of linear matrix inequalities. The validity of the proposed control method is illustrated by a numerical example. 相似文献
2.
《Drug metabolism and pharmacokinetics》2019,34(5):308-316
LC-MS quantification of drug metabolites is sometimes impeded by the availability of internal standards that often requires customized synthesis and/or extensive purification. Although isotopically labeled internal standards are considered ideal for LC-MS/MS based quantification, de novo synthesis using costly isotope-enriched starting materials makes it impractical for early stage of drug discovery. Therefore, quick access to these isotope-enriched compounds without chemical derivatization and purification will greatly facilitate LC-MS/MS based quantification. Herein, we report a novel 18O-labeling technique using metabolizing enzyme carboxylesterase (CES) and its potential application in metabolites quantification study. Substrates of CES typically undergo a two-step oxygen exchange with H218O in the presence of the enzyme, generating singly- and doubly-18O-labeled carboxylic acids; however, unexpected hydrolytic behavior was observed for three of the test compounds – indomethacin, piperacillin and clopidogrel. These unusual observations led to the discovery of several novel hydrolytic mechanisms. Finally, when used as internal standard for LC-MS/MS based quantification, these in situ labeled compounds generated accurate quantitation comparable to the conventional standard curve method. The preliminary results suggest that this method has potential to eliminate laborious chemical synthesis of isotope-labeled internal standards for carboxylic acid-containing compounds, and can be developed to facilitate quantitative analysis in early-stage drug discovery. 相似文献
3.
目的探讨评教评学模式在肿瘤外科护理带教中的应用效果。方法选择2017年6月—2019年2月于该院肿瘤外科实习的88名护生作为该次研究对象,随机将护生分为对照组与观察组,两组分别有护生44名,对照组给予传统带教方法,观察组给予评教评学模式带教,比较两组护生的护理带教结果。结果观察组护生对带教老师综合能力评价优良率是92.0%,对照组评价优良率是76.0%,组间对比差异有统计学意义(χ^2=4.192,P=0.041<0.05)。观察组带教老师对护生综合能力评价优良率是90.9%,对照组评价优良率是72.7%,组间对比差异有统计学意义(χ^2=4.889,P=0.027<0.05)。观察组护生的理论知识与实操技能考核成绩均要显著比对照组高,差异有统计学意义(P<0.05)。结论评教评学模式在肿瘤外科护理带教中具有显著应用价值,可充分激发师生的教学积极性,改善护理教学质量。 相似文献
4.
Detection of Atrial Fibrillation by Implanted Devices with Wireless Data Transmission Capability 总被引:3,自引:0,他引:3
NIRAJ VARMA† BRUCE STAMBLER SUNG CHUN† 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S133-S136
Remote telemetry may facilitate the management of implantable devices. We tested the reliability of a new automatic, wireless home monitoring (HM) system that archives data every 24 hours. We retrospectively analyzed archival data from 276 consecutive pacing system implants to define temporal atrial fibrillation (AF) patterns and associated ventricular rate. An "AF day" was defined by a >20%/24 hour mode switch (MS) duration, irrespective of the MS number. Management decisions resulting from transmissions were noted. A pilot study confirmed that 89% of 22,356 transmissions were successful, of which >90% were received in <5 minutes. Data integrity was 100% preserved. Overall, AF developed in 29 patients (10.5%), representing a total of 645 AF days (mean = 22.2 ± 29.6 AF, median = 9 days), over 12 ± 2 months of monitoring. AF was infrequent (50% of 24 hours. Ventricular rates during 645 AF days in 29 patients averaged 95.1 ± 9.9 beats/min (median = 94 beats/min). Ventricular rates were >80 beats/min in 25 ± 30 AF days (median = 11 days). HM enabled rapid anticoagulation decisions. In recipients of implantable devices, automatic wireless telemetry with HM was efficient and reliable. Its application may overcome some current challenges in AF management by early notification and precise measurement of both AF burden and ventricular rate during AF. 相似文献
5.
I was honored to study the undergraduate course in Hong Kong Polytechnic University for 4 months in 2006, experienced the characteristic and teaching mode of Hong Kong nursing education on undergraduate course personally. Make an introduction from respects such as course offered, teaching method, educational idea, examination way, etc. now, and compare with domestic nursing education. 相似文献
6.
Hiromitsu Nakaya Shuichi Kawashiri Akira Tanaka Natsuyo Noguchi Koroku Kato Takashi Hase Etsuhide Yamamoto 《Journal of oral pathology & medicine》2005,34(2):87-92
BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion. 相似文献
7.
以部队装备和士兵体质现状为基础,制定了士兵体能训练卫生规范。《规范》主要规定了以下三部分内容:①部队士兵进行基本体能训练应遵循循序渐进、超负荷训练及适宜恢复等生理卫生要求;耐力、力量和柔韧性训练的方式、强度和时间;体能训练的组织实施等,以使体能训练负荷与机体的生理状态相适应;②体能训练的卫生监督,针对体能训练中可能遇到的医学问题进行监督,能够防止训练伤、过度疲劳及其它医学事故的出现,保障体能训练的顺利进行;③体能训练的医学效果评价。本标准适用于陆军部队士兵基本体能训练。海、空军地勤部队士兵的体能训练亦可参照执行。 相似文献
8.
移情对建立新型医患关系伦理模式的利与弊 总被引:1,自引:0,他引:1
在现代社会这样一个转轨时期,医患矛盾越来越突出,如何缓和医患关系、建立新型医患关系伦理模式成为大家共同关心的课题。作者从移情的角度入手,阐述了新型医患关系伦理模式的内涵,分析了移情对于缓和医患关系有哪些有利之处与不利之处,并提出了如何适度利用移情的方法,使其发挥最大作用。 相似文献
9.
[目的]探讨不同起搏模式对病人生存质量(QOL)的影响。[方法]以健康调查问卷(SF一36量表)对112例不同起搏模式病人进行问卷调查,比较3种起搏模式下病人的QOL水平。[结果]除机体疼痛、角色情绪2个维度外其余6个维度(生理功能、角色限制、活力、社会功能、精神健康、总体健康)3种起搏模式间比较差异有统计学意义(P〈0.05)。[结论]应用AAI型、DDD型起搏器的病人生存质量优于VVI型起搏。 相似文献
10.
董剑桥 《南通大学学报(哲学社会科学版)》2002,18(2):131-135
外语学习软件界面的设计除了应注意实现软件功能的技术因素、表现媒体的物理性状以及信息内容的学科把握 ,还应对软件界面的内容组织方略、交互通达方式、语用认知功能等方面提出要求。界面设计的出发点 ,应该是学生、学习任务及其相应的学习活动。应该根据需求分析、学习者分析、任务和内容分析来确定目标和步骤。外语教学应以语言能力、交际能力、学习策略能力为目标 ,界面设计应以此为据选择表现媒体、结构层次、交互方式和技术手段。 相似文献