27 research outputs found

    Micromechanical study of the load transfer in a polycaprolactone-collagen hybrid scaffold when subjected to unconfined and confined compression

    Get PDF
    Scaffolds are used in diverse tissue engineering applications as hosts for cell proliferation and extracellular matrix formation. One of the most used tissue engineering materials is collagen, which is well known to be a natural biomaterial, also frequently used as cell substrate, given its natural abundance and intrinsic biocompatibility. This study aims to evaluate how the macroscopic biomechanical stimuli applied on a construct made of polycaprolactone scaffold embedded in a collagen substrate translate into microscopic stimuli at the cell level. Eight poro-hyperelastic finite element models of 3D printed hybrid scaffolds from the same batch were created, along with an equivalent model of the idealized geometry of that scaffold. When applying an 8% confined compression at the macroscopic level, local fluid flow of up to 20 [Formula: see text]m/s and octahedral strain levels mostly under 20% were calculated in the collagen substrate. Conversely unconfined compression induced fluid flow of up to 10 [Formula: see text]m/s and octahedral strain from 10 to 35%. No relevant differences were found amongst the scaffold-specific models. Following the mechanoregulation theory based on Prendergast et al. (J Biomech 30:539-548, 1997. https://doi.org/10.1016/S0021-9290(96)00140-6 ), those results suggest that mainly cartilage or fibrous tissue formation would be expected to occur under unconfined or confined compression, respectively. This in silico study helps to quantify the microscopic stimuli that are present within the collagen substrate and that will affect cell response under in vitro bioreactor mechanical stimulation or even after implantation

    Development of a multi-dimensional measure of resilience in adolescents: the Adolescent Resilience Questionnaire

    Get PDF
    Background: The concept of resilience has captured the imagination of researchers and policy makers over the past two decades. However, despite the ever growing body of resilience research, there is a paucity of relevant, comprehensive measurement tools. In this article, the development of a theoretically based, comprehensive multidimensional measure of resilience in adolescents is described.Methods: Extensive literature review and focus groups with young people living with chronic illness informed the conceptual development of scales and items. Two sequential rounds of factor and scale analyses were undertaken to revise the conceptually developed scales using data collected from young people living with a chronic illness and a general population sample.Results: The revised Adolescent Resilience Questionnaire comprises 93 items and 12 scales measuring resilience factors in the domains of self, family, peer, school and community. All scales have acceptable alpha coefficients. Revised scales closely reflect conceptually developed scales.Conclusions: It is proposed that, with further psychometric testing, this new measure of resilience will provide researchers and clinicians with a comprehensive and developmentally appropriate instrument to measure a young person&rsquo;s capacity to achieve positive outcomes despite life stressors.<br /

    Building and Sustaining Community-Institutional Partnerships for Prevention Research: Findings from a National Collaborative

    No full text
    The Examining Community-Institutional Partnerships for Prevention Research Project began in October 2002 with funding from the Centers for Disease Control and Prevention Research Center Program Office through a cooperative agreement between the Association of Schools of Public Health and the CDC. The three-year project aimed to synthesize knowledge about community-institutional partnerships for prevention research and to build community and institutional capacity for participatory research. These ten organizations collaborated on the project because they were all involved in community-institutional partnerships for prevention research, had access to research and evaluation data on these partnerships, and believed that the shared learning and action that would result through a collaborative effort could significantly advance collective knowledge about partnerships and lead to substantive capacity-building responses: the Community Health Scholars Program, Community-Based Public Health Caucus of the American Public Health Association, Community–Campus Partnerships for Health, Detroit Community-Academic Urban Research Center, Harlem Health Promotion Center, National Community Committee of the CDC Prevention Research Centers Program, New York Urban Research Center, Seattle Partners for Healthy Communities, Yale-Griffin Prevention Research Center and the Wellesley Institute. This paper reports on the project’s findings, including common characteristics of successful partnerships and recommendations for strengthening emerging and established partnerships
    corecore