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71.
David C. Hughes Leslie M. Baehr David S. Waddell Adam P. Sharples Sue C. Bodine 《International journal of molecular sciences》2022,23(14)
The development and prevalence of diseases associated with aging presents a global health burden on society. One hallmark of aging is the loss of proteostasis which is caused in part by alterations to the ubiquitin–proteasome system (UPS) and lysosome–autophagy system leading to impaired function and maintenance of mass in tissues such as skeletal muscle. In the instance of skeletal muscle, the impairment of function occurs early in the aging process and is dependent on proteostatic mechanisms. The UPS plays a pivotal role in degradation of misfolded and aggregated proteins. For the purpose of this review, we will discuss the role of the UPS system in the context of age-related loss of muscle mass and function. We highlight the significant role that E3 ubiquitin ligases play in the turnover of key components (e.g., mitochondria and neuromuscular junction) essential to skeletal muscle function and the influence of aging. In addition, we will briefly discuss the contribution of the UPS system to lifespan. By understanding the UPS system as part of the proteostasis network in age-related diseases and disorders such as sarcopenia, new discoveries can be made and new interventions can be developed which will preserve muscle function and maintain quality of life with advancing age. 相似文献
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75.
Microstructural and Residual Stress Development due to Inertia Friction Welding in Ti-6246 总被引:1,自引:0,他引:1
76.
Michael G. Hughes Jennifer A. Griffith Thomas A. Zeni Matthew L. Arsenault Olivia D. Cooper Genevieve Johnson Jay H. Hardy Shane Connelly Michael D. Mumford 《Journal of Computer-Mediated Communication》2014,19(3):325-341
Given the prevalence of online media today, credibility continues to be a popular subject of empirical research. However, studies examining the effects of discrediting strategies are rare. This issue is significant given the popularity of online media and the ease of such sources to spread misinformation. Therefore, the present study examines the effects of attacking the expertise and trustworthiness of a proponent of a major social issue. Results showed that support as well specific combinations of discrediting attack strategies significantly reduced message board readers' perceptions of the proponent's credibility. In addition, attacks on either the proponent's expertise or trustworthiness resulted in a reduced likelihood of readers taking action with respect to the issue. 相似文献
77.
Jens Georg Kaufmann Marc P. Y. Desmulliez Yingtao Tian Dennis Price Mike Hughes Nadia Strusevich Chris Bailey Changqing Liu David Hutt 《Microsystem Technologies》2009,15(8):1245-1254
In this paper we propose an agitation method based on megasonic acoustic streaming to overcome the limitations in plating
rate and uniformity of the metal deposits during the electroplating process. Megasonic agitation at a frequency of 1 MHz allows
the reduction of the thickness of the Nernst diffusion layer to less than 600 nm. Two applications that demonstrate the benefits
of megasonic acoustic streaming are presented: the formation of uniform ultra-fine pitch flip-chip bumps and the metallisation
of high aspect ratio microvias. For the latter application, a multi-physics based numerical simulation is implemented to describe
the hydrodynamics introduced by the acoustic waves as they travel inside the deep microvias. 相似文献
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79.
J. Donald Hughes 《Landscape Research》2013,38(1):21-31
Landscapes at the edge of the city comprise vast areas that ‘lie fallow’, awaiting future urban development. During this time new landscape values evolve. It is argued that the complexity of urban fringe landscapes is not adequately considered either within landscape research or in the practice of spatial planning. A key to understanding landscapes at the inner urban fringe is to focus on landscape dynamics, and on the interactions between spatial plans and everyday activities. The study is divided into three parts. First, theoretical considerations about landscape dynamics and the character of the inner urban fringe are presented. Thereafter, the relationship between spatial planning and everyday places is analysed in a case-study area at the edge of the city of Malmö in southernmost Sweden. The case study demonstrates the complexity of landscape dynamics at the inner urban fringe, as well as problems regarding the handling of ephemeral and transitory aspects within spatial planning. The study concludes with a discussion concerning the importance of studies of landscape dynamics within landscape research. 相似文献
80.
Kazadi N. Mutoji Mingxia Sun Garrett Elliott Isabel Y. Moreno Clare Hughes Tarsis F. Gesteira Vivien J. Coulson-Thomas 《International journal of molecular sciences》2021,22(11)
Corneal transparency relies on the precise arrangement and orientation of collagen fibrils, made of mostly Type I and V collagen fibrils and proteoglycans (PGs). PGs are essential for correct collagen fibrillogenesis and maintaining corneal homeostasis. We investigated the spatial and temporal distribution of glycosaminoglycans (GAGs) and PGs after a chemical injury. The chemical composition of chondroitin sulfate (CS)/dermatan sulfate (DS) and heparan sulfate (HS) were characterized in mouse corneas 5 and 14 days after alkali burn (AB), and compared to uninjured corneas. The expression profile and corneal distribution of CS/DSPGs and keratan sulfate (KS) PGs were also analyzed. We found a significant overall increase in CS after AB, with an increase in sulfated forms of CS and a decrease in lesser sulfated forms of CS. Expression of the CSPGs biglycan and versican was increased after AB, while decorin expression was decreased. We also found an increase in KS expression 14 days after AB, with an increase in lumican and mimecan expression, and a decrease in keratocan expression. No significant changes in HS composition were noted after AB. Taken together, our study reveals significant changes in the composition of the extracellular matrix following a corneal chemical injury. 相似文献