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Adaptation of Skeletal Muscle to Prolonged Activity: Role of Myosin

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Health 2019年第2期11卷 195-200页

作者： Teet Seene Karin Alev Priit Kaasik Institute of Sport Sciences and Physiotherapy University of Tartu Tartu Estonia

The aim of this short review is to describe the role of myosin isoforms during the adaptation of skeletal muscle to prolonged physical activity (for example endurance exercise) and to show the coordination between changes in muscle oxidative capacity and myofibrillar apparatus in slow-twitch and fast-twitch muscles. Adaptational changes in myosin isoforms during long lasting muscle activity (decrease of MyHC IIb isoforms relative content and increase of that MyHC IIa and decrease of MyLC 1 fast isoforms in fast-twitch muscles) are in good coordination with changes of muscle oxidative capacity. These changes show that during regular endurance exercise fast-twitch muscle fibers (type IIA) are also recruited and create the potential source of increase in endurance capacity during the process of adaptation to the prolonged physical activity.

关键词： Prolonged Muscle Activity endurance Exercise Myosin Light Chain Myosin Heavy Chain endurance Capacity

Environmental Impact of High Altitudes on the Operation of PEM Fuel Cell Based UAS

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Energy and Power Engineering 2018年第3期10卷 87-105页

作者： Ibrahim M. Saleh Rashid Ali Hongwei Zhang Materials and Engineering Research Institute Sheffield Hallam University Sheffield UK Faculty of Engineering Environment and Computing Coventry University Coventry UK

Fuel cell is a device that converts the chemical energy in the reactants into the electrical energy after steps of sequential electrochemical processes with no significant impact on the environment. For high altitude long endurance (HALE) of unmanned aircraft system (UAS) where fuel cell operates as a prime source of power, the operation and performance of a PEM fuel cell at different level of altitudes is vitally important. In this paper, the impact of direct using extracted air from high altitudes atmosphere in order to feed the stack is investigated, and the governing equations of the supplied air and oxygen to the PEM fuel cell stack are developed. The impact of high altitudes upon the operation and the consumption of air are determined in order to maintain certain level of delivered power to the load. Also the implications associated with operating the PEM fuel cell stack at high altitudes and different technical solutions are proposed. Various modes of Integral, Proportional-Integral, and Proportional-Integral-Derivative controller are introduced and examined for different time setting responses in order to determine the most adequate trade-off choice between fast response and reactants consumption which provides the necessary optimization of the air consumption for the developed model of PEM fuel cell used for UAS operation.

关键词： PEM Fuel Cell High Altitude Long endurance PID Controller UAS

Passive Whole-Body Hyperthermia Increases Aerobic Capacity and Cardio-Respiratory Efficiency in Amateur Athletes

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Health 2020年第1期12卷 14-26页

作者： Maxim A. Zapara Elena N. Dudnik Vlada G. Samartseva Svetlana Yu. Kryzhanovskaya Davide Susta Oleg S. Glazachev Department of Normal Physiology I. M. Sechenov First Moscow State Medical University (Sechenov University) Moscow Russia School of Health and Human Performance Dublin City University Dublin Ireland

Objective: The research was carried out to test the influence of adaptation to passive whole body hyperthermia (PH) on physical capacity and cardio-respiratory efficiency in men-amateur athletes under the testing load of increasing intensity in laboratory thermal-neutral conditions. Twenty-eight amateur athletes (males, mean age 20.2 ± 2.1 y.o., game-based kinds of sports—football, handball, training experience—4 - 7 years) were randomized into two groups: experimental (14 people), who underwent 24 PH procedures, and control (14 people), who underwent 24 light training sessions in interval regime on elliptical gym apparatus. Results: Adaptation to PH was accompanied by moderate increase of aerobic efficiency and cardio-respiratory endurance in amateur athletes under thermally neutral conditions, while interval training in the control group showed no reliable changes in efficiency. Conclusion: A 10-week course of PH procedures leads to the increase of peak oxygen consumption, oxygen consumption at the level of anaerobic threshold, and heart efficiency (enhancement of oxygen pulse values), as well as efficiency of pulmonary ventilation and bronchial conductance, which we consider to be cross effects of adaptation to passive whole-body repetitive hyperthermia.

关键词： Adaptation Amateur Athletes endurance Passive Whole-Body Hyperthermia Aerobic Capacity

Effect of aging on the relationship between capillary supply and muscle fiber size

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Advances in Aging Research 2013年第1期2卷 37-42页

作者： Yutaka Kano Kunihiro Sakuma Department of Engineering Science Bioscience and Technology Program University of Electro-Communications Tokyo Japan Research Center for Physical Fitness Sports and Health Toyohashi University of Technology Toyohashi Japan

A quantitative analysis of capillary supply to skeletal muscle is important for understanding the upper limit of the capacity for delivery of oxygen and substrates to muscle cells. It has been well documented that the number of capillaries is altered by several factors including development, aging, and alteration of muscle activity level such as exercise training and inactivation. There is, however, a contradiction in animal studies for aging-related change in the number of capillaries. Human studies using biopsy technique also displayed an inconsistency on that point, in which capillary supply was not influenced or decreased with aging. This review discussed an inconsistency among studies for aging-related change in muscle capillary supply. In conclusion, the relationship between capillary supply and muscle fiber size is similar for both young and elderly population, and the morpho- logical balance between capillaries and each muscle fiber was maintained with advancing age.

关键词： Skeletal Muscle endurance Training Resistance Training Capillary Luminal Diameter

Muscle damage and regeneration: Response to exercise training

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Health 2013年第6期5卷 136-145页

作者： Teet Seene Priit Kaasik Institute of Exercise Biology and Physiotherapy University of Tartu Tartu Estonia Institute of Exercise Biology and Physiotherapy University of Tartu Tartu Estonia

Exercise training influences the function of skeletal muscle, modifying fibre structure, metabolism and promoting the release of growth factors and other signalling molecules. The number of satellite cells under the basal lamina of type I and type IIA muscle fibres increases during endurance training and under the basal lamina of both type II fibres during resistance training. An increase in satellite cells is related to several factors expressing different genes and type II muscle fibre hypertrophy. Insulin-like growth factor-I has a role in the hypertrophy of muscle fibres through the stimulation of the differentiation of satellite cells. The increased mitochondrial biogenesis via adenosine myophosphate-activated protein kinase is accompanied by the suppression of myofibrillar protein synthesis through pathways mediated by mitogen-activated protein kinases and the nuclear factor kappa B. Insulin-like growth factor-I expression is higher in type I fibres. Myostatin, the expression inhibitor of muscle hypertrophy, is higher in type II fibres. The proteasome-, lysosome- and Ca2+-mediated protein degradation is more intensive in fibres with higher oxidative capacity. Both, oxidative capacity and satellite cells number in muscle fibres play important roles in skeletal muscle regeneration. In this review, we explore the regeneration capacity changes in different types of skeletal muscle fibres in response to resistance, endurance and overtraining.

关键词： Skeletal Muscle Regeneration Capacity Resistance endurance and Overtraining

The Yo-Yo tests and twelve-minute run test performance in young Japanese cross-country skiers

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Open Journal of Preventive Medicine 2013年第2期3卷 246-250页

作者： Denda Yuki Oh Taewoong Nakajima Setsuko Graduate School of Health Science Matsumoto University Matsumoto Japan

Purpose: The aim of the present study is to examine the performance of young Japanese cross-country skiers of different competitive levels with the use of Yo-Yo tests and the 12-minute run test (12MRT) that have been demonstrated to be related to each level, and to know which test is suitable for different competitive performance. Methods: Elite group (N = 9) was 16.9 ± 0.3 years and moderate trained group (N = 22) was 16.1 ± 0.9 years. The testing sessions consisted of the following: 1) Vertical jump and 50m sprint;2) the Yo-Yo tests level 1 and 2 (intermittent recovery);3) 12MRT. Results: Results showed the vertical jump heights and 50m sprint that no significant both performances differences were found among the two groups. Significant the Yo-Yo tests and 12MRT performances differences were found between the two groups (p < 0.05). Performance test (%) showed the ratio of moderate trained group towards elite group. The Yo-Yo tests performance was low enough compared with the result of 12MRT in moderate trained group. Conclusions: It is therefore valid to assume that low Yo-Yo tests performance due to immature anaerobic in cross-country skiers was a new limiting factor in the competitive level.

关键词： Yo-Yo Intermittent Recovery Tests endurance Sports Aerobic Anaerobic Performance

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0.13μm EEPROM器件测试分析

0.13μm EEPROM器件测试分析

作者：喻尊电子科技大学

学位级别：硕士

EEPROM (Electrically Erasable Programmable Read-Only Memory),电可擦写只读存储器,是一种掉电后数据不丢失、可在线重复擦写编程的存储器,通常写入的数据常温条件下可以保存数十年,其擦写编程周期可达百万次以上。作为理想的小容量... 详细信息

EEPROM (Electrically Erasable Programmable Read-Only Memory),电可擦写只读存储器,是一种掉电后数据不丢失、可在线重复擦写编程的存储器,通常写入的数据常温条件下可以保存数十年,其擦写编程周期可达百万次以上。作为理想的小容量不易失存储器(NVM, Nonvolatile Memory),广泛应用于消费类电子、工业类电子等产品领域。本文以复旦微电子股份有限公司与新加坡特许半导体联合开发的0.13μm EEPROM工艺开发及器件验证项目为中心,结合不易失存储器理论及自开发测试验证平台介绍,分析验证工艺、器件特性。本文的主要工作包括:1)NVM器件基本理论研究。首先,对NVM涉及相关半导体物理机理进行分析和研究;其次,对常用三类NVM类型(EPROM、EEPROM、Flash)及各类型存储器典型单元特征结构进行分析和研究。2)0.13μm EEPROM单元、阵列及EEPROM工艺介绍。对本项目EEPROM目标存储单元和存储阵列及开发工艺进行简要介绍。3)自开发测试验证平台介绍。测试验证平台主要包含NB0401测试系统,安捷伦电源、安捷伦万用表、精准温控气流箱、自开发PCB测试板,单片机测试程序及测试脚本,通过对测试流程的分析加以描述。4)工艺器件验证、特性分析。器件特性主要包含EEPROM单元的阈值电压VT与擦、写编程高压VPP、编程时间TEW关系,endurance特性退化,数据保持能力和温度特性。目前0.13μm EEPROM工艺已经成功开发完成,器件结构已成熟应用于公司的串行EEPROM产品及智能卡产品。

关键词： EEPROM 不易失存储器 endurance 器件结构数据保持

0.35微米SONOS非易失存储器件可靠性的改善研究

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0.35微米SONOS非易失存储器件可靠性的改善研究

作者：李占斌上海交通大学

学位级别：硕士

随着市场对Flash存储器件集成度要求的不断提高,传统Flash器件数据存储的可靠性与器件的工作速度、功耗、尺寸等方面的矛盾日益凸现。普遍认为,在45nm工艺以下,基于多晶硅浮栅结构的传统Flash技术势必会被新一代的存储器件所取代。因此... 详细信息

随着市场对Flash存储器件集成度要求的不断提高,传统Flash器件数据存储的可靠性与器件的工作速度、功耗、尺寸等方面的矛盾日益凸现。普遍认为,在45nm工艺以下,基于多晶硅浮栅结构的传统Flash技术势必会被新一代的存储器件所取代。因此,基于新型存储机理的NVM引起了科研工作者们的广泛关注,包括SONOS存储器、nm存储器、相变存储器(PCM)、铁电随机存储器(Fe RAM)、磁性随机存储器(MRAM)。其中SONOS存储器用―硅(基底)-隧穿氧化硅-氮化硅-阻挡氧化硅(Blocking Oxide)-多晶硅‖(Silicon-Oxide-Nitride- Oxide-Silicon, SONOS)栅堆层替代了传统Flash存储器件中的浮栅结构,是一种电荷陷阱型存储器。它在结构和工艺技术上与传统Flash最为接近,最有可能在短时间内有效取代传统Flash的存储器。文章针对某公司0.35μm SONOS非易失存储器件可靠性方面存在的不足,首先从非易失性存储器件SONOS的电荷传输机理进行分析。而后从改善ONO叠层结构和组成ONO叠层结构的材料上进行优化研究。在实验的部分,将利用In-Situ ONO的形成方法生长隧穿氧化层-氮化硅层-阻断氧化层(ONO),行成SONOS结构,对SONOS结构电容器进行C-V与I-V特性的量测与分析,来确认量子点捕获电荷的能力。接着利用此结构进行存储元件的制作,完成的组件进行记忆写入/读取特性之量测,并进一步确认通过改变影响SONOS可靠性参数对SONOS结构可靠性的影响. 文章主要通过改善GOX前清洗对HTO厚度的影响来改善Data retention,通过Oxy-nitride grading改善Data retention和endurance。通过在ONO叠层中引入ND3改善Data retention和endurance、通过在Tunneling oxide中引入N2O改善endurance、最终达到提高SONOS存储器的可靠性的目的。研究表明通过改善SONOS结构的可靠性的相关参数Data retention和endurance,可以明显改善器件的可靠性。在实验的部分,将利用In-Situ ONO的形成方法生长隧穿氧化层-氮化硅层-阻断氧化层(ONO),行成SONOS结构,对SONOS结构电容器进行C-V与I-V特性的量测与分析,来确认量子点捕获电荷的能力。接着利用此结构进行存储元件的制作,完成的组件进行记忆写入/读取特性之量测,并进一步确认通过改变影响SONOS可靠性参数对SONOS结构可靠性的影响.

关键词： SONOS器件 Data retention endurance 可靠性

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微软群集服务不再是您惟一的选择

Windows & Net Magazine（国际中文版） 2004年第8M期 19-31页

作者： JohnGreen 陈流浩 NereusComputerConsulting公司的总裁不详

当您面对着几个9的选择时，是否只有微软的MSCS才是惟一的选择?今天，许多第三方生产商提供了比过去更为简洁、成熟的群集产品来实现一个高可用性解决方案。如何找到一个真正的容错解决方案，或是实现群集服务节点上数据的远程可用性?... 详细信息

当您面对着几个9的选择时，是否只有微软的MSCS才是惟一的选择?今天，许多第三方生产商提供了比过去更为简洁、成熟的群集产品来实现一个高可用性解决方案。如何找到一个真正的容错解决方案，或是实现群集服务节点上数据的远程可用性?本文将有助于您判断出哪一个解决方案最适合您的需求和实际情况。

关键词：群集服务体系结构 SCSI 共享存储异步复制 endurance PolyServe矩阵服务器