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排序方式: 共有6014条查询结果,搜索用时 15 毫秒
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Daniel H. Mendelsohn Katja Schnabel Andreas Mamilos Samuel Sossalla Steffen Pabel Georg Daniel Duerr Karsten Keller Volker H. Schmitt Friedrich Barsch Nike Walter Ronald Man Yeung Wong Thaqif El Khassawna Tanja Niedermair Volker Alt Markus Rupp Christoph Brochhausen 《International journal of molecular sciences》2022,23(9)
Mitochondria play a crucial role in cell physiology and pathophysiology. In this context, mitochondrial dynamics and, subsequently, mitochondrial ultrastructure have increasingly become hot topics in modern research, with a focus on mitochondrial fission and fusion. Thus, the dynamics of mitochondria in several diseases have been intensively investigated, especially with a view to developing new promising treatment options. However, the majority of recent studies are performed in highly energy-dependent tissues, such as cardiac, hepatic, and neuronal tissues. In contrast, publications on mitochondrial dynamics from the orthopedic or trauma fields are quite rare, even if there are common cellular mechanisms in cardiovascular and bone tissue, especially regarding bone infection. The present report summarizes the spectrum of mitochondrial alterations in the cardiovascular system and compares it to the state of knowledge in the musculoskeletal system. The present paper summarizes recent knowledge regarding mitochondrial dynamics and gives a short, but not exhaustive, overview of its regulation via fission and fusion. Furthermore, the article highlights hypoxia and its accompanying increased mitochondrial fission as a possible link between cardiac ischemia and inflammatory diseases of the bone, such as osteomyelitis. This opens new innovative perspectives not only for the understanding of cellular pathomechanisms in osteomyelitis but also for potential new treatment options. 相似文献
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In this paper, we identify two cases in which the proposition for calculating time window penalties presented in Nagata, Y., Bräysy, O. and Dullaert, W. A penalty-based edge assembly memetic algorithm for the vehicle routing problem with time windows, Computers & Operations Research 2010;37(4): 724–37 yields incorrect results. We derive the corrected proposition and use numerical studies to show that a significant proportion of the evaluations performed by a Tabu Search for VRPTW falls under the two incorrect cases. Moreover, we demonstrate that the incorrect time window handling has a significant negative impact on the solution quality of the Tabu Search. 相似文献
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Dadhichi Paretkar Marleen Kamperman Andreas S. Schneider David Martina Costantino Creton Eduard Arzt 《Materials science & engineering. C, Materials for biological applications》2011,31(6):1152-1159
We developed a dry synthetic adhesive system inspired by gecko feet adhesion that can switch reversibly from adhesion to non-adhesion with applied pressure as external stimulus. Micropatterned polydimethylsiloxane (PDMS) surfaces with pillars of 30 μm length and 10 μm diameter were fabricated using photolithography and moulding. Adhesion properties were determined with a flat probe as a function of preload. For low and moderate applied compressive preloads, measured adhesion was 7.5 times greater than on flat controls whereas for high applied preloads adhesion dropped to very low values. In situ imaging shows that the increased preload caused the pillars to deform by bending and/or buckling and to lose their adhesive contact. The elasticity of PDMS aids the pillar recovery to the upright position upon removal of preload enabling repeatability of the switch. 相似文献
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PROven(R)系统的开发为了减少焦炉的排放,过去已进行了多种技术的开发.但是从焦炉炉门、装料孔边缘等处逸散物的减少,已受到工艺技术的制约.一个基本的制约因素是,在集气总管内的压力和联接到总管的所有碳化室内的压力之间有着密不可分的关系. 相似文献
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Various types of electric machines can be considered for an application to integrated starter generator (ISG). Permanent magnet (PM) synchronous machines present interesting performances; nevertheless, it remains difficult to reach a significant constant power zone under good efficiency conditions and power factor. The loss of control of electronics at high-speed operations may lead to high-terminal voltages, which can become dangerous for the whole vehicle. In this study, we examine the main advantages and drawbacks of the induction machine, reluctant, and PM machine. Then we present more precisely the wound rotor synchronous machine (WRSM) performances for ISG applications. All these machines must follow strict rules and specifications (low length, high torque, speed, and efficiency). Different kinds of machines have already been evaluated. 相似文献