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The design and fabrication of a membrane-integrated microfluidic cell culture device (five layers,≤500 μm total thickness) developed for high resolution microscopy is reported here. The multi-layer device was constructed to enable membrane separated cell culture for tissue mimetic in vitro model applications and pharmacodynamic evaluation studies. The microdevice was developed via a unique combination of low profile fluidic interconnect design, substrate transfer methodology, and wet silane bonding. To demonstrate the unique high resolution imaging capability of this device, we used oil immersion microscopy to image stained nuclei and mitochondria in primary hepatocytes adhered to the incorporated membrane  相似文献   
975.
In this work a disposable, parallel microbioreactor (MBR) suitable for screening in batch or continuous mode is presented. The reactor consists of five parallel microchambers made of poly(dimethylsiloxane) bonded to a glass substrate. A grid structure is engraved on each chamber, allowing subsequent morphology imaging. Measurements are recorded over the entire cultivation period with constant parameters, namely, position and focus in the z-axis. The microdevice may be used for either parallel, uni- or multiparametric screening, and overcomes the drawback of gridless microwell plates which require expensive equipment such as an inverted microscope with an automatic stage. To validate the scalability from laboratory scale to microscale, and thus the cultivation protocol in the MBR, the germination of fungal spores (A. ochraceus) is evaluated for two different key magnitudes (pH and temperature) and compared to the results obtained from conventional laboratory scale systems (flasks and agar plates). Information on germination capacity with regard to interspecies' variability allows for optimization of industrial processes as optimal pH and temperature matched to the mesoscopic cultivation systems. The germination conditions therefore remain unaffected inside the MBR, while providing the following advantages: (i) dramatic reduction of medium consumption, (ii) submerged cultivation with constant oxygen supply, (iii) assured low cost and disposability, and (iv) possibility of a continuous cultivation mode.  相似文献   
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977.
Maximum oxygen uptake (VO(2PEAK)) is generally considered to be the best single marker for aerobic fitness. While a positive relationship between daily physical activity and aerobic fitness has been established in adults, the relationship appears less clear in children and adolescents. The purpose of this paper is to summarise recently published data on the relationship between daily physical activity, as measured by accelerometers, and VO(2PEAK) in children and adolescents. A PubMed search was performed on 29 October 2010 to identify relevant articles. Studies were considered relevant if they included measurement of daily physical activity by accelerometry and related to a VO(2PEAK) either measured directly at a maximal exercise test or estimated from maximal power output. A total of nine studies were identified, with a total number of 6116 children and adolescents investigated. Most studies reported a low-to-moderate relationship (r = 0.10-0.45) between objectively measured daily physical activity and VO(2PEAK). No conclusive evidence exists that physical activity of higher intensities are more closely related to VO(2PEAK), than lower intensities.  相似文献   
978.
Although triathlon is growing in popularity at a remarkable rate, it has not been extensively studied. The aims of this research were to identify preparation strategies used by triathletes and to categorize these strategies according to gender and consultation with triathlon coaches. Survey data collected from 401 triathletes (207 males, 194 females) revealed training, nutritional, and mental preparation habits. Most participants engaged in strength training, consumed food and/or fluids during and after training, set training and competition goals, and applied mental preparation strategies during training and the hour before racing. Water was the most commonly consumed fluid; positive self-talk was the most used mental strategy. Participants were more likely to consult with a triathlon coach than a nutrition or sport psychology professional. Athletes with more years of experience in triathlon and those competing in longer distances were more likely to consult a triathlon coach. Female triathletes were more likely than male triathletes to train with others, use mental preparation strategies, and report feeling anxious before competitions. More male triathletes reported using nutritional supplements during training than their female counterparts. These findings add to the limited research base on triathletes' training habits, and hopefully will help guide practitioners who work with this group. The results provide guidance for collaborative efforts among training, nutrition, and mental health professionals to best support triathletes.  相似文献   
979.

BISp-Informationen

BISp Informationen  相似文献   
980.

BISp-Informationen

Informationen des Bundesinstituts für Sportwissenschaft (BISp)  相似文献   
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