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In this study, we investigated the adjustments to posture, kinematic and temporal characteristics of performance made by lower limb amputees during the last few strides in preparation for long jump take-off. Six male unilateral trans-femoral and seven male unilateral trans-tibial amputees competing in a World Championships final were filmed in the sagittal plane using a 100-Hz digital video camera positioned so that the last three strides to take-off were visible. After digitizing using a nine-segment model, a range of kinematic variables were computed to define technique characteristics. Both the trans-femoral and trans-tibial athletes appeared to achieve their reduction in centre of mass during the flight phase between strides, and did so mainly by extending the flight time by increasing stride length, achieved by a greater flexion of the hip joint of the touch-down leg. The trans-tibial athletes appeared to adopt a technique similar to that previously reported for able-bodied athletes. They lowered their centre of mass most on their second last stride (-1.6% of body height compared with -1.4% on the last stride) and used a flexed knee at take-off on the last stride, but they were less able to control their downward velocity at touch-down (-0.4 m x s(-1)). Both this and their restricted approach speed (8.9 m x s(-1) at touch-down), rather than technique limitations, influenced their jump performance. The trans-femoral athletes lowered their centre of mass most on the last stride (-2.3% of body height compared with -1.6% on the second last stride) and, as they were unable to flex their prosthetic knee sufficiently, achieved this by abducting their prosthetic leg during the support phase, which led to a large downward velocity at touch-down (-0.6 m x s(-1)). This, combined with their slower approach velocity (7.1 m x s(-1) at touch-down), restricted their performance.  相似文献   
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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   
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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   
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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   
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