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21.
Shay Oved Merav Mofaz Anat Lan Haim Einat Noga Kronfeld-Schor Dan Yamin Erez Shmueli 《Journal of the Royal Society Interface》2021,18(179)
The unprecedented restrictions imposed due to the COVID-19 pandemic altered our daily habits and severely affected our well-being and physiology. The effect of these changes is yet to be fully understood. Here, we analysed highly detailed data on 169 participants for two to six months, before and during the second COVID-19 lockdown in Israel. We extracted 12 well-being indicators from sensory data of smartwatches and from self-reported questionnaires, filled daily using a designated mobile application. We found that, in general, lockdowns resulted in significant changes in mood, sleep duration, sport duration, social encounters, resting heart rate and number of steps. Examining subpopulations, we found that younger participants (aged 20–40 years) suffered from a greater decline in mood and number of steps than older participants (aged 60–80 years). Likewise, women suffered from a higher increase in stress and reduction in social encounters than men. Younger early chronotypes did not increase their sleep duration and exhibited the highest drop in mood. Our findings underscore that while lockdowns severely impacted our well-being and physiology in general, greater damage has been identified in certain subpopulations. Accordingly, special attention should be given to younger people, who are usually not in the focus of social support, and to women. 相似文献
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Goldstein Anat Johanndeiter Thomas Frank Ulrich 《Information Systems and E-Business Management》2019,17(1):27-64
Information Systems and e-Business Management - Business process management (BPM) broadly covers a lifecycle of four distinct phases: design, configuration, enactment, and analysis and evaluation.... 相似文献
24.
Robin H.M. van der Meijden Deniz Daviran Luco Rutten X. Frank Walboomers Elena Macías-Sánchez Nico Sommerdijk Anat Akiva 《Advanced functional materials》2023,33(42):2212339
Osteons, the main organizational components of human compact bone, are cylindrical structures composed of layers of mineralized collagen fibrils, called lamellae. These lamellae have different orientations, different degrees of organization, and different degrees of mineralization where the intrafibrillar and extrafibrillar minerals are intergrown into one continuous network of oriented crystals. While cellular activity is clearly the source of the organic matrix, recent in vitro studies call into question whether the cells are also involved in matrix mineralization and suggest that this process could be simply driven by the interactions of the mineral with extracellular matrix. Through the remineralization of demineralized bone matrix, the complete multiscale reconstruction of the 3D structure and composition of the osteon without cellular involvement are demonstrated. Then, this cell-free in vitro system is explored as a realistic, functional model for the in situ investigation of matrix-controlled mineralization processes. Combined Raman and electron microscopy indicate that glycosaminoglycans (GAGs) play a more prominent role than generally assumed in the matrix–mineral interactions. The experiments also show that the organization of the collagen is in part a result of its interaction with the developing mineral. 相似文献
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Anat Akiva Johanna Melke Sana Ansari Nalan Liv Robin van der Meijden Merijn van Erp Feihu Zhao Merula Stout Wouter H. Nijhuis Cilia de Heus Claudia Muñiz Ortera Job Fermie Judith Klumperman Keita Ito Nico Sommerdijk Sandra Hofmann 《Advanced functional materials》2021,31(17):2010524
Bone formation (osteogenesis) is a complex process in which cellular differentiation and the generation of a mineralized organic matrix are synchronized to produce a hybrid hierarchical architecture. To study the mechanisms of osteogenesis in health and disease, there is a great need for functional model systems that capture in parallel, both cellular and matrix formation processes. Stem cell-based organoids are promising as functional, self-organizing 3D in vitro models for studying the physiology and pathology of various tissues. However, for human bone, no such functional model system is yet available. This study reports the in vitro differentiation of human bone marrow stromal cells into a functional 3D self-organizing co-culture of osteoblasts and osteocytes, creating an organoid for early stage bone (woven bone) formation. It demonstrates the formation of an organoid where osteocytes are embedded within the collagen matrix that is produced by the osteoblasts and mineralized under biological control. Alike in in vivo osteocytes, the embedded osteocytes show network formation and communication via expression of sclerostin. The current system forms the most complete 3D living in vitro model system to investigate osteogenesis, both in physiological and pathological situations, as well as under the influence of external triggers (mechanical stimulation, drug administration). 相似文献
26.
Feldman AR Leung EK Bennet AJ Sen D 《Chembiochem : a European journal of chemical biology》2006,7(1):98-105
Much interest has focused on the mechanisms of the five naturally occurring self-cleaving ribozymes, which, in spite of catalyzing the same reaction, adopt divergent strategies. These ribozymes, with the exception of the recently described glmS ribozyme, do not absolutely require divalent metal ions for their catalytic chemistries in vitro. A mechanistic investigation of an in vitro-selected, RNA-cleaving DNA enzyme, the bipartite, which catalyzes the same chemistry as the five natural self-cleaving ribozymes, found a mechanism of significant complexity. The DNAzyme showed a bell-shaped pH profile. A dissection of metal usage indicated the involvement of two catalytically relevant magnesium ions for optimal activity. The DNAzyme was able to utilize manganese(II) as well as magnesium; however, with manganese it appeared to function complexed to either one or two of those cations. Titration with hexaamminecobalt(III) chloride inhibited the activity of the bipartite; this suggests that it is a metalloenzyme that utilizes metal hydroxide as a general base for activation of its nucleophile. Overall, the bipartite DNAzyme appeared to be kinetically distinct not only from the self-cleaving ribozymes but also from other in vitro-selected, RNA-cleaving deoxyribozymes, such as the 8-17, 10-23, and 614. 相似文献
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The strong shift toward operating in global markets has posed enormous adaptation challenges for product marketing especially with regard to universality and consistency of brand design decisions. The color‐in‐product design decision is also susceptible to this global–local tension. A pharmaceutical film coating formulator supplier to leading local and global pharmaceutical companies was interested in developing a solid validated global color preference database to enable informed brand decision making for its customers. The following study reports results from a global survey that examined the color–brand attribute associations within the global pharmaceutical industry. Data were collected from a multigeography gender and age balanced sample of 2021 subjects, revealing a strikingly powerful color language comprised of universally consistent associations and local contextual patterns that are each critical to global brand decision makers within this industry. © 2011 Wiley Periodicals,Inc. Col Res Appl, 2012; 相似文献
29.
A porous, homochiral titanium‐phosphonate material based on a tripodal peptide scaffold was used as a heterogeneous reaction medium for the enantioselective hydration (>99%) of styrene oxide. This titanium‐phosphonate material, which was shown to contain confined chiral spaces, was prepared by polymerization of L ‐leucine onto a tris(2‐aminoethyl)amine initiator, followed by capping with phosphonate groups and completed by non‐aqueous condensation with titanium isopropoxide. Circular dichroism confirmed that the peptide tethers yielded a secondary structure. X‐ray powder diffraction and transmission electron microscopy supported by a semi‐empirical model showed the likely formation of a porous, lamellar material that was quantified by nitrogen adsorption. 相似文献
30.
The present study focused on innovation of teams, examining the contributions of team interaction processes (exchanging information, learning, motivating, and negotiating) and structures (functional heterogeneity and frequency of meetings) to innovation. Specifically, it was hypothesized that (a) team structures will be positively related to team innovation, (b) team heterogeneity will be positively related to team interaction processes, (c) team interaction processes will be positively related to team innovation, and (d) team interaction processes will mediate the relationship between team heterogeneity and team innovation. Results from a sample of 48 intact teams in elementary and secondary schools supported the main hypotheses. These results imply that the development of mutual interaction processes is a crucial mechanism for translating team heterogeneity into innovation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献