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Modeling and Analysis of a Micromotor with an Electrostatically Levitated Rotor

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 1-8页

作者： HAN Fengtian wu qiuping ZHANG Rong Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

The modeling and evaluation of a prototype rotary micromotor where the annular rotor is supported electrostatically in five degrees of freedom is presented in order to study the behavior of this levitated micromotor and further optimize the device geometry. The analytical torque model is obtained based on the principle of a planar variable-capacitance electrostatic motor while the viscous damping caused by air film between the stator and rotor is derived using laminar Couette flow model. Simulation results of the closed-loop drive motor, based on the developed dynamic model after eliminating mechanical friction torque via electrostatic suspension, are presented. The effects of the high-voltage drive, required for rotation of the rotor, on overload capacity and suspension stiffness of the electrostatic bearing system are also analytically evaluated in an effort to determine allowable drive voltage and attainable rotor speed in operation. The analytical results show that maximum speed of the micromotor is limited mainly by viscous drag torque and stiffness of the bearing system. Therefore, it is expected to operate the device in vacuum so as to increase the rotor speed significantly, especially for those electrostatically levitated micromotors to be used as an angular rate micro-gyroscope.

关键词： electrostatic levitation electrostatic micromotor variable-capacitance motor micro-gyroscope

Development of Chinese herbal medicine for sensorineural hearing loss

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Acta Pharmaceutica Sinica B 2024年第2期14卷 455-467页

作者： Yunhao wu Jingwen Zhang qiuping Liu Zhuang Miao Renjie Chai Wenyong Chen State Key Laboratory of Bioelectronics Department of Otolaryngology Head and Neck SurgeryZhongda HospitalSchool of Life Sciences and TechnologyAdvanced Institute for Life and HealthJiangsu Province HighTech Key Laboratory for Bio-Medical ResearchSoutheast UniversityNanjing 210096China Department of Otolaryngology-Head and Neck the Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510120China Department of Otolaryngology-Head and Neck Surgery Affiliated Hospital of Jiangnan UniversityWuxi 214000China Department of Otolaryngology Head and Neck Surgery Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610000China Co-Innovation Center of Neuroregeneration Nantong UniversityNantong 226001China Institute for Stem Cell and Regeneration Chinese Academy of ScienceBeijing 100085China Beijing Key Laboratory of Neural Regeneration and Repair Capital Medical UniversityBeijing 100069China

According to the World Health Organization’s world report on hearing,nearly 2.5 billion people worldwide will suffer from hearing loss by 2050,which may contribute to a severe impact on individual life quality and national *** hearing loss(SNHL)occurs commonly as a result of noise exposure,aging,and ototoxic drugs,and is pathologically characterized by the impairment of mechanosensory hair cells of the inner ear,which is mainly triggered by reactive oxygen species accumulation,inflammation,and mitochondrial *** recent advances have been made in understanding the ability of cochlear repair and regeneration,there are still no effective therapeutic drugs for *** herbal medicine which is widely distributed and easily accessible in China has demonstrated a unique curative effect against SNHL with higher safety and lower cost compared with Western *** we present trends in research for Chinese herbal medicine for the treatment of SNHL,and elucidate their molecular mechanisms of action,to pave the way for further research and development of novel effective drugs in this field.

关键词： Sensorineural hearing loss Chinese herbal medicine Molecular mechanism Active ingredients Prescriptions Ototoxic drugs Noise Hair cells

麻醉住培医师的认知负荷变化对高保真情景模拟教学效果的影响研究

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中华医学教育探索杂志 2024年第4期23卷 548-555页

作者：裴皓玉胡弋王丽代娟孙琪祝幸冉小利吴秋平毛庆祥陆军特色医学中心麻醉科重庆400042 陆军军医大学第二附属医院心内科重庆400037

目的探究麻醉住培医师的认知负荷变化对高保真情景模拟教学效果的影响。方法选取2022年2月至11月某三甲医院87名麻醉住培医师为研究对象,按随机数字法将麻醉住培生分为A、B、C组,从麻醉危机资源教学案例库抽取3个病例,采用交叉设计控制... 详细信息

目的探究麻醉住培医师的认知负荷变化对高保真情景模拟教学效果的影响。方法选取2022年2月至11月某三甲医院87名麻醉住培医师为研究对象,按随机数字法将麻醉住培生分为A、B、C组,从麻醉危机资源教学案例库抽取3个病例,采用交叉设计控制培训案例次序,分别对3组麻醉住培医师进行高保真模拟培训,每轮培训由训前指导、模拟教学和培训后总结分析3部分组成。3轮模拟教学后对所有研究对象进行认知负荷、焦虑状态、考核成绩和非技术技能评价。采用SPSS 20.0进行重复测量方差分析和Pearson相关性检验。结果3组住培医师在第一轮模拟培训期间的认知负荷、焦虑评分均高于第二、三轮,第一轮考核成绩[(87.07±5.66)、(88.38±5.41)、(89.07±6.17)]低于第二轮[(95.69±2.29)、(96.10±2.08)、(96.07±2.60)]和第三轮[(96.34±1.45)、(96.38±1.50)、(96.17±1.73)]的考核成绩;第一轮的非技术技能评分[(37.24±7.58)、(38.69±7.27)、(39.24±8.74)]也分别低于第二轮[(46.17±5.55)、(47.07±5.59)、(47.59±6.74)]和第三轮[(47.17±5.21)、(48.48±5.38)、(48.24±6.83)],差异有统计学意义(P<0.05)。在同一模拟案例中,第一轮培训学员的认知负荷和焦虑也高于第二、三轮的学员,考核成绩和非技术技能评分低于第二、三轮,差异有统计学意义(P<0.05)。结论首次情景模拟培训麻醉学员具有较高的认知负荷和焦虑水平,并降低学习效果;多次模拟训练可以减轻学员的认知负荷和焦虑。

关键词：认知负荷理论高保真模拟麻醉住院医师培训学习效果焦虑状态

Root growth in response to nitrogen supply in Chinese maize hybrids released between 1973 and 2009

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Science China(Life Sciences) 2011年第7期54卷 642-650页

作者： wu qiuping CHEN FanJun CHEN YanLing YUAN LiXing ZHANG FuSuo MI GuoHua Key Laboratory of Plant-Soil Interaction MOE College of Resources and Environmental Science China Agricultural University Beijing 100193 China

Root growth has a fundamental role in nitrogen (N) use ***,little is known about how modern breeding progress has affected root growth and its responses to N *** root and shoot growth of a core set of 11 representative Chinese maize (Zea mays L.) hybrids released between 1973 and 2009 were investigated under high N (4 mmol L?1,HN) and low N (0.04 mmol L?1,LN) levels in a solution culture *** with LN,HN treatment decreased root dry weight (RDW),the root:shoot ratio (R/S),and the relative growth rate for root dry weight (RGRroot),but increased the total root length (TRL) and the total lateral root length (LRL).The total axial root length (ARL) per plant was reduced under HN,mostly in hybrids released before the *** number of seminal roots (SRN) was largely unaffected by different N *** recently released hybrids showed higher relative growth rates in the shoot under both HN and ***,the roots only showed increased RGR under HN ***,there was a positive linear relationship with the year of hybrid release for TRL,LRL and ARL under HN ***,these results suggest that while shoot growth of maize has improved,its root growth has only improved under high N conditions over the last 36 years of selective breeding in *** root growth under LN conditions may be necessary to increase the N use efficiency of maize.

关键词：根系生长氮素供应玉米中国混合动力车新梢生长施氮水平调制解调器

Ideotype root architecture for efficient nitrogen acquisition by maize in intensive cropping systems

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Science China(Life Sciences) 2010年第12期53卷 1369-1373页

作者： MI GuoHua CHEN FanJun wu qiuping LAI NingWei YUAN LiXing ZHANG FuSuo Key Laboratory of Plant Nutrition MOAKey Laboratory of Plant-Soil InteractionMOECollege of Resources and Environmental ScienceChina Agricultural UniversityBeijing 100193China

The use of nitrogen(N) fertilizers has contributed to the production of a food supply sufficient for both animals and humans despite some negative environmental *** food production by increasing N use efficiency in intensive cropping systems has become a major concern for scientists,environmental groups,and agricultural policymakers *** high-yielding maize systems the major method of N loss is nitrate *** this review paper,the characteristic of nitrate movement in the soil,N uptake by maize as well as the regulation of root growth by soil N availability are *** suggest that an ideotype root architecture for efficient N acquisition in maize should include(i) deeper roots with high activity that are able to uptake nitrate before it moves downward into deep soil;(ii) vigorous lateral root growth under high N input conditions so as to increase spatial N availability in the soil;and(iii) strong response of lateral root growth to localized nitrogen supply so as to utilize unevenly distributed nitrate especially under limited N conditions.

关键词： maize nitrogen use efficiency root architecture nitrate rhizosphere

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生酮饮食对肥胖型哮喘的影响

中华结核和呼吸杂志 2022年第2期45卷 222-226页

作者：孔璐丹吴秋萍浙江大学医学院附属儿童医院国家儿童健康与疾病临床医学研究中心杭州310052

肥胖和支气管哮喘(以下简称哮喘)之间的相关性日益受到关注,70%难治性哮喘患者超重或肥胖,肥胖已成为哮喘的重要危险因素。近年来,生酮饮食作为自然疗法之一,被证实有治疗肥胖症的作用,并且也有研究指出生酮饮食可降低哮喘气道炎症。本... 详细信息

肥胖和支气管哮喘(以下简称哮喘)之间的相关性日益受到关注,70%难治性哮喘患者超重或肥胖,肥胖已成为哮喘的重要危险因素。近年来,生酮饮食作为自然疗法之一,被证实有治疗肥胖症的作用,并且也有研究指出生酮饮食可降低哮喘气道炎症。本文总结了肥胖与哮喘的关联机制,阐述了生酮饮食影响肥胖型哮喘的潜在机制,如控制体重,减轻炎症反应,调节肠道菌群和修饰表观遗传,为肥胖型哮喘的防治提供新的思路。

关键词：难治性哮喘生酮饮食肥胖型支气管哮喘自然疗法危险因素肥胖症表观遗传

线上信息差与意见差任务中的协商互动及对口语输出的影响

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世界汉语教学 2022年第3期36卷 416-430页

作者：伍秋萍向娜中山大学中文系国际汉语中心

本研究以“城乡差异”和“旅游城市”为话题设计信息差和意见差对话任务,通过整合协商互动和即时总结发言的输出语料,考察中级汉语二语学习者对话过程中的协商互动及对口语输出的影响。协商互动的语料分析结果显示:(1)学习者在配对小组... 详细信息

本研究以“城乡差异”和“旅游城市”为话题设计信息差和意见差对话任务,通过整合协商互动和即时总结发言的输出语料,考察中级汉语二语学习者对话过程中的协商互动及对口语输出的影响。协商互动的语料分析结果显示:(1)学习者在配对小组中的协商互动约占对话话轮的三分之一,内容协商数量显著多于意义和形式协商;(2)学习者在信息差任务中出现了更多的“澄清请求”和“确认核查”两类发起方式和更多的“解释”反馈,而意见差任务中学习者更常使用“诱发”发起协商,并通过“肯定或否定”及“补充”给予反馈。两类任务即时总结发言的语料分析显示,学习者口语输出的流利度和准确度较高、复杂度偏低,其中口语输出的词汇复杂度可被同伴互动过程中内容协商的数量显著预测。

关键词：协商互动口语输出信息差任务意见差任务

Effects of narrow plant spacing on root distribution and physiological nitrogen use efficiency in summer maize

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The Crop Journal 2013年第1期1卷 77-83页

作者： Wenshun Jiang Kongjun Wang qiuping wu Shuting Dong Peng Liu Jiwang Zhang State Key Laboratory of Crop Biology/Agronomy College Shandong Agricultural University

The objective of this study was to understand the effects of plant spacing on grain yield and root competition in summer maize(Zea mays L.). Maize cultivar Denghai 661 was planted in rectangular tanks(0.54 m × 0.27 m × 1.00 m) under 27 cm(normal) and 6 cm(narrow) plant spacing and treated with zero and 7.5 g nitrogen(N) per plant. Compared to normal plant spacing, narrow plant spacing generated less root biomass in the 0–20 cm zone under both N rates, slight reductions of dry root weight in the 20–40 cm and 40–70 cm zones at the mid-grain filling stage, and slight variation of dry root weights in the 70–100 cm zone during the whole growth period. Narrow plant spacing decreased root reductive activity in all root zones, especially at the grain-filling stage. Grain yield and above-ground biomass were 5.0% and 8.4% lower in the narrow plant spacing than with normal plant spacing, although narrow plant spacing significantly increased N harvest index and N use efficiency in both grain yield and biomass, and higher N translocation rates from vegetative organs. These results indicate that the reductive activity of maize roots in all soil layers and dry weights of shallow roots were significantly decreased under narrow plant spacing conditions, resulting in lower root biomass and yield reduction at maturity. Therefore, a moderately dense sowing is a basis for high yield in summer maize.

关键词： Zea mays Root reductive activity Nitrogen uptake and utilization Nutrient gradient zone

The forensic pathological analysis of sport-related sudden cardiac death in Southern China

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Forensic Sciences Research 2020年第1期5卷 47-54页

作者： Yeda wu Mei Ai Adham Sameer A.Bardeesi Liyong Zhang qiuping wu Kun Yin Jingjing Zheng Da Zheng Lei Huang Lunwu Xu Jianding Cheng Department of Forensic Pathology Zhongshan School of MedicineSun Yat-Sen UniversityGuangzhouChina Forensic Science Center of Waston GuangzhouChina Branch Office of Yanping Public Security Bureau of NanpingNanpingChina

Studies regarding sport-related sudden cardiac death(SCD)mainly focus on competitive ath-letes;similar data are rare in the general population,especially in *** conducted a retrospective study(from September 1998 to August 2013)to investigate the aetiological distribution and epidemiological features of sport-related SCD in Southern *** of cases are based on details,and two subgroups were established:one was the sport-related SCD group,and the other was the disease-free accident victims group which was matched with the sport-related SCD group in gender,age and year of *** the 3770 sudden-death cases,1656 cases were SCD cases.A total of 65 cases(57 males)out of 1656 SCD cases were *** age range of the 65 sport-related SCD cases was from 12 to 68 years old with a mean(35.92±14.23)years *** two of these cases were competitive *** most common circumstances of the 65 sport-related SCD cases were heavy physical labour(46.15%)and running(30.77%).The three leading forensic diag-noses were the coronary atherosclerotic disease(CAD,28 cases),cardiomyopathy(CM,14 cases)and sudden unexplained death(7 cases).CM was the most common forensic diagno-sis in those?35 years old,while CAD was the most common one in those>35 years *** anterior descending in which atherosclerotic plaques was most commonly found was the principal artery branch associated with sport-related *** was a statistically signifi-cant difference in the weight of hearts between the 65 sport-related SCD cases and 65 dis-eases-free accidental *** study highlights the need to attract public attention to sport-related SCD and to issue a prevention strategy to the public,and to make the SCD-related genetic sequencing a routine tool in both forensic pathological examination and clinic screening.

关键词： Forensic sciences forensic pathology sport sudden death cardiac coronary disease cardiomyopathies