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101.
Cartilage injuries are often devastating and most cannot be cured because of the intrinsically low regenerative capacity of cartilage tissues. Although stem-cell therapy has shown enormous potential for cartilage repair, the therapeutic outcome has been restricted by low survival rates and poor chondrocyte differentiation in vivo. Here, we report an injectable hybrid inorganic (IHI) nanoscaffold that facilitates fast assembly, enhances survival and regulates chondrogenic differentiation of stem cells. IHI nanoscaffolds that strongly bind to extracellular matrix (ECM) proteins assemble stem cells through synergistic 3D cell–cell and cell–matrix interactions, creating a favorable physical microenvironment for stem-cell survival and differentiation in vitro and in vivo. Additionally, chondrogenic factors can be loaded into nanoscaffolds with a high capacity, which allows deep, homogenous drug delivery into assembled 3D stem-cell-derived tissues for effective control over the soluble microenvironment of stem cells. The developed IHI nanoscaffolds that assemble with stem cells are injectable. They also scavenge reactive oxygen species and timely biodegrade for proper integration into injured cartilage tissues. Implantation of stem-cell-assembled IHI nanoscaffolds into injured cartilage results in accelerated tissue regeneration and functional recovery. By establishing our IHI nanoscaffold-templated 3D stem-cell assembly method, we provide a promising approach to better overcoming the inhibitory microenvironment associated with cartilage injuries and to advance current stem-cell-based tissue engineering.  相似文献   
102.
Many American and European art museums are now featuring small, highly-focused shows in their exhibition programs. In 1990, the Indianapolis Museum of Art organized an exhibition that reunited, for the first time in a century, the four landscape paintings created by neo-impressionist Georges Seurat during the last summer of his life. Using Seurat at Gravelines: The Last Landscapes as an example, this article addresses the advantages — for museums and their visitors — of the small temporary exhibition.  相似文献   
103.
This study examined differences in written expression between a sample of learning-disabled and nondisabled middle school students, matched by grade and sex, using eight curriculum-based measures. All of the learning-disabled students had been identified as having written language deficits as part of their handicapping conditions. The nondisabled students showed superior written expression skills, especially on the production-independent measures. Implications of these results are discussed in relation to psycho educational assessment, the use of CBM for ongoing assessment of written expression, and future studies.  相似文献   
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Background:Farmworker-serving community health workers have limited access to farmworker health research findings, training, and education resources. With funding from the National Library of Medicine, we are working to improve the health information literacy of both community health workers and farmworkers. We conducted focus group discussions with community health workers to explore their experiences providing health education and information to farmworkers, their information-seeking behaviors, and their technology and information needs. Data from the focus groups provided insights into the main areas in which community health workers would like to receive professional development.Case Presentation:Our team, which includes health sciences librarians, developed a resource list of educational materials for farmworker health, videos to increase community health workers'' skills finding health information online, and webinars to introduce these resources to community health workers. Videos, available in Spanish and English, included instruction on finding and evaluating online health information, accessing reputable online consumer health information sources, and advanced searching tips for Google and PubMed. Through three webinars, we introduced the resource list, videos, and design software for creating handouts and infographics to community health workers.Conclusions:Community health workers have a critical role in providing health education and information to farmworkers, and our efforts represent a first step in addressing community health workers'' limited access to professional development. Health sciences librarians are well positioned to partner with interdisciplinary teams working to reduce health disparities and provide resources and training to community health workers, farmworkers, and other underserved communities.  相似文献   
106.
BackgroundOne-hour postprandial hyperglycemia is associated with increased risk of type 2 diabetes and cardiovascular disease. Physical activity (PA) has short-term beneficial effects on post-meal glucose response. This study compared the oral glucose tolerance test results of 3 groups of people with habitually different levels of PA.MethodsThirty-one adults without diabetes (age 25.9 ± 6.6 years; body mass index 23.8 ± 3.8 kg/m2; mean ± SD) were recruited and divided into 3 groups based on self-reported PA volume and intensity: low activity < 30 min/day of moderate-intensity activity (n = 11), moderately active ≥ 30 min/day of moderate-intensity PA (n = 10), and very active ≥ 60 min/day of PA at high intensity (n = 10). Participants completed an oral glucose tolerance test (50 g glucose) with capillary blood samples obtained at baseline, 15 min, 30 min, 45 min, 60 min, 90 min, and 120 min post-ingestion.ResultsThere were no significant differences between groups for age or body fat percentage or glycated hemoglobin (p > 0.05). The groups were significantly different in terms of baseline glucose level (p = 0.003) and, marginally, for gender (p = 0.053) and BMI (p = 0.050). There was a statistically significant effect of PA on the 1-h postprandial glucose results (p = 0.029), with differences between very active and low activity groups (p = 0.008) but not between the moderately active and low activity groups (p = 0.360), even when baseline glucose level and gender differences were accounted for. For incremental area under the curve there was no significant effect of activity group once gender and body fat percentage had been accounted for (p = 0.401). Those in the low activity group took 15 min longer to reach peak glucose level than those in the very active group (p = 0.012).ConclusionThe results suggest that high levels of PA have a beneficial effect on postprandial blood glucose profiles when compared to low and moderate levels of activity.  相似文献   
107.
从后现代主义的起源、流变及其表现形式来看,后现代主义思潮具有反传统、反理性、多元化、自组织等特征.这种思潮已经波及科学及教育领域,正在并将继续对教育科学的理论及实战产生诸多正面、负面的影响.  相似文献   
108.
Tracing one's family genealogy is a complex process that requires situating a family's narratives within a historical context. This article reviews the use of critical family history research in an undergraduate Asian American studies course to examine not only the diversity and experiences of Asian Americans but also the unspoken narratives that lead to the creation of a single story. We are told single stories that often neglect the sociocultural factors—the historical reality—of our past. Our family histories are constructed historically and are embedded in social, political, and economic processes and relationships. This article argues that we need to complicate what we know about our past and examine policies and cultural practices that lead to a racialized system of power and privilege, racialized policies, and racialized oppression and progression.  相似文献   
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