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Johan von Essen 《Foundations of Science》2016,21(2):343-346
Due to Swedish history, to date there has been a common understanding of the meaning of volunteering in Sweden. However, it seems as if the meaning of volunteering is changing in Sweden, at least in some atypical hybrid organizations. However, this change presupposes that there is a conception of volunteering that has been institutionalized by tradition. Hence, to understand this change, one has to capture the institutionalized meaning of volunteering. In the academic debate there is sometimes an implied opposition between conceptual meaning and existential meaning. It is argued that this divide is unfortunate, the existential aspect presupposes the conceptual aspect of meaning. The study of the meaning of volunteering is an attempt to uncover existential meaning in everyday life. Neither the cognitive meaning nor the existential meaning of volunteering is an objective fact but fragile and dependent upon contextual factors. 相似文献
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Zohra Dhouafli Karina Cuanalo-Contreras El Akrem Hayouni Charles E. Mays Claudio Soto Ines Moreno-Gonzalez 《Cellular and molecular life sciences : CMLS》2018,75(19):3521-3538
Protein misfolding and aggregation into fibrillar deposits is a common feature of a large group of degenerative diseases affecting the central nervous system or peripheral organs, termed protein misfolding disorders (PMDs). Despite their established toxic nature, clinical trials aiming to reduce misfolded aggregates have been unsuccessful in treating or curing PMDs. An interesting possibility for disease intervention is the regular intake of natural food or herbal extracts, which contain active molecules that inhibit aggregation or induce the disassembly of misfolded aggregates. Among natural compounds, phenolic molecules are of particular interest, since most have dual activity as amyloid aggregation inhibitors and antioxidants. In this article, we review many phenolic natural compounds which have been reported in diverse model systems to have the potential to delay or prevent the development of various PMDs, including Alzheimer’s and Parkinson’s diseases, prion diseases, amyotrophic lateral sclerosis, systemic amyloidosis, and type 2 diabetes. The lower toxicity of natural compounds compared to synthetic chemical molecules suggest that they could serve as a good starting point to discover protein misfolding inhibitors that might be useful for the treatment of various incurable diseases. 相似文献
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The paleoflow direction of the basal conglomerate of the Changzhougou formation is obtained by the paleocurrent analysis of certain sedimentary structures, and the ancient sedimentary environment of the Qian'an Region is determined by observing the psephicity and gradation of gravel in conglomerate. The results show that the paleoflow direction is from northwest to southwest, and the paleocurrent data manifest a single-peak style in a rose diagram. The average paleoflow direction in the Qian'an region is 265°. The basal conglomerate is of littoral facies, and the sediments of conglomerates are mainly sourced from Shanhaiguan. 相似文献
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This paper is devoted to the investigation of stability for a class of coupled impulsive Markovian jump reaction-diffusion systems on networks (CIMJRDSNs). By using graph theory, a systematic method is provided to construct global Lyapunov functions for the CIMJRDSNs. Based on Lyapunov functions and stochastic analysis method, some novel stability principles associated with the topology property of the networks are established. 相似文献
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Periostin is a matricellular protein that is composed of a multi-domain structure with an amino-terminal EMI domain, a tandem repeat of four FAS 1 domains, and a carboxyl-terminal domain. These distinct domains have been demonstrated to bind to many proteins including extracellular matrix proteins (Collagen type I and V, fibronectin, tenascin, and laminin), matricellular proteins (CCN3 and βig-h3), and enzymes that catalyze covalent crosslinking between extracellular matrix proteins (lysyl oxidase and BMP-1). Adjacent binding sites on periostin have been suggested to put the interacting proteins in close proximity, promoting intermolecular interactions between each protein, and leading to their assembly into extracellular architectures. These extracellular architectures determine the mechanochemical properties of connective tissues, in which periostin plays an important role in physiological homeostasis and disease progression. In this review, we introduce the proteins that interact with periostin, and discuss how the multi-domain structure of periostin functions as a scaffold for the assembly of interacting proteins, and how it underlies construction of highly sophisticated extracellular architectures. 相似文献