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11.
Biosynthetic microspheres have the potential to address some of the limitations in cell microencapsulation; however, the generation of biosynthetic hydrogel microspheres has not been investigated or applied to cell encapsulation. Droplet microfluidics has the potential to produce more uniform microspheres under conditions compatible with cell encapsulation. Therefore, the aim of this study was to understand the effect of process parameters on biosynthetic microsphere formation, size, and morphology with a co-flow microfluidic method. Poly(vinyl alcohol) (PVA), a synthetic hydrogel and heparin, a glycosaminoglycan were chosen as the hydrogels for this study. A capillary-based microfluidic droplet generation device was used, and by varying the flow rates of both the polymer and oil phases, the viscosity of the continuous oil phase, and the interfacial surface tension, monodisperse spheres were produced from ∼200 to 800 μm. The size and morphology were unaffected by the addition of heparin. The modulus of spheres was 397 and 335 kPa for PVA and PVA/heparin, respectively, and this was not different from the bulk gel modulus (312 and 365 for PVA and PVA/heparin, respectively). Mammalian cells encapsulated in the spheres had over 90% viability after 24 h in both PVA and PVA/heparin microspheres. After 28 days, viability was still over 90% for PVA-heparin spheres and was significantly higher than in PVA only spheres. The use of biosynthetic hydrogels with microfluidic and UV polymerisation methods offers an improved approach to long-term cell encapsulation.  相似文献   
12.
参加有组织的体育运动和休闲活动存在发生严重伤病甚至死亡的内在风险。虽然造成体育运动或体育活动中猝死的原因有很多,但运动医学和循证标准治疗方面的进展已使临床医生得以更有效地预防、发现和治疗可能致死的伤患。随着研究与技术不断发展进步,当前的治疗标准正在不断发展以更好地改善患者的治疗效果。本文提出了10个与运动和体育活动中猝死的主要原因及其治疗手段有关的关键问题,未来开展的研究将提高运动员和休闲运动爱好者参与运动的安全度。当前证据表明,如采取正确的预防策略或最佳治疗方案,绝大多数的死亡案例是可以避免的。  相似文献   
13.
The aim of this study was to examine the maturation responses of young people to submaximal treadmill exercise. Body mass was controlled using both the conventional ratio standard and allometric modelling. Ninety-seven boys and 97 girls with a mean age of 12.2 years completed a discontinuous, incremental exercise test to voluntary exhaustion. We measured peak oxygen uptake (VO2peak) and VO2 when running at 8, 9 and 10 km x h(-1). Sexual maturation was assessed visually using Tanner's indices of pubic hair. Peak VO2 was significantly higher in boys (P<0.001); this was still the case when the influence of body mass was covaried out. During submaximal exercise, no significant differences in absolute VO2 were observed between the sexes (P>0.05); however, values of VO2, expressed both in ratio with body mass and adjusted for body mass using allometry, were significantly greater in boys than in girls (P<0.001). For absolute VO2, significant main effects (P<0.05) were seen for maturity at each exercise stage. With the influence of body mass controlled using either the ratio standard or allometry, no significant main effects (P>0.05) for maturity were observed. Our results indicate that boys are less economical than girls while running at 8-10 km x h(-1) and that, independently of body mass, maturation does not influence the VO2 response to submaximal exercise.  相似文献   
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Three of the most prevalent developmental disorders (DDs) are autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD) and fetal alcohol spectrum disorder (FASD). As part of a study screening for DDs in Greater Manchester, UK, a unique opportunity was taken to explore parents' experiences of receiving reports about their child's previously unrecognised DD. Six parents out of a possible 16 took part in interviews, which were analysed thematically. Findings drawn from parental responses revealed a number of barriers to accessing support for their child's additional needs, including perceived resistance from schools, particularly for quiet, well-behaved girls, and difficulty in accessing assessment or referrals. There needs to be greater awareness of additional needs in children without externalising behaviours, the presence of gender-specific differences in the presentation of DDs, and FASD as a commonly occurring DD. Ultimately, better support for children with DDs would reduce the burden of unmet needs for the children and their families, and for wider services.  相似文献   
17.
In this case study, we assessed academic functioning, service satisfaction, and needs of student veterans at a community college who had accessed the Veterans Health Administration (VHA) Student Veteran Health Program (SVHP) (n = 36). The SVHP provides outreach and behavioral health services directly on a large community college campus to overcome common barriers to engagement in mental health care (e.g., distance from a VA medical center). Academic difficulties that were most commonly reported were in the areas of retention of information, meeting deadlines, and cooperation with other students. Overall, the majority of student veterans who received services in the SVHP were satisfied (76.5%). Services targeting attention and concentration and utilization of educational benefits were highlighted as important by student veterans. This case study of VA services delivered within the community college setting provides important insights into how to design VA services to target the needs of student veterans. Specific recommendations for supporting student veterans on a community college campus are discussed.  相似文献   
18.
Gender distinction has been shown to characterise both undergraduate experiences and outcomes. Yet research recounted in this article supports work that shows that young people are often unaware of such trends, subscribing instead to individualist perspectives that foreground equality of opportunity and agency. This article examines the gender continuities and divergences in 64 undergraduate students' accounts of their experiences, and constructions of peers and lecturers, in higher education. Concepts of heteroglossia and monoglossia are applied to gender to explain how students submerged ‘structure’ and inequality in their accounts, but how discourses that presented the genders as distinct (and in which the masculine is elevated over the feminine) nevertheless ‘bubbled up’ in their articulations. The students tended to reject the notion that gender and other structural differences impact their experiences and outcomes; yet their broader discussions frequently reflected (often stereotypical) monoglossic constructions of gender difference. The article concludes with a discussion of the implications of these findings for the sociology of education and for higher-education pedagogy.  相似文献   
19.
For democracies to thrive, citizens have to be taught to be democrats. How do people learn to be democrats in circumstances of diversity and plurality? We address this question via a discussion of three models of deliberative democracy: public reason (as exemplified by Rawls), discursive democracy (as exemplified by Benhabib) and communicative democracy (as exemplified by Young). Each of the three theorists contributes to an account of how to educate citizens by teaching talk. Against a commonly held assumption that the protection of diversity in a pluralist democracy requires a thin conception of citizenship education, we defend a thick conception that simultaneously fosters autonomy and participation without sacrificing tolerance of diversity.  相似文献   
20.
International Journal of Science and Mathematics Education - Role models are critical for broadening participation in science, technology, engineering, and mathematics (STEM); however, little is...  相似文献   
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