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941.
In this mixed-methods study, we examine students’ gratitude for their teachers and the implications of that gratitude for their psychological adaptation. We report findings that gratitude for teachers (GT) is, in fact, a resource for students facing difficult circumstances outside school. More specifically, our hierarchical multiple regression models demonstrate that this form of gratitude decreases the negative association between adverse life events and students’ life satisfaction. GT also decreases the positive association between negative life events and students’ perceived stress. Then, we use coded material from student interviews to illustrate how they understand the ways that their GT helps them manage challenges in their personal lives. We conclude that students’ GT buffers the negative impact of adverse life events, because it helps students attend to the positive interactions and mentorship they have with their teachers and maintain focus on their future-oriented goals.  相似文献   
942.
Science & Education - In this article, we draw upon the Conceptual Profile Theory to discuss the negotiation of meanings related to the energy concept in an 11th grade physics classroom. This...  相似文献   
943.
In this paper we develop a new framework for time series segmentation based on a Hierarchical Linear Dynamical System (HLDS), and test its performance on monophonic and polyphonic musical note recognition. The center piece of our approach is the inclusion of constraints in the filter topology, instead of on the cost function as normally done in machine learning. Just by slowing down the dynamics of the top layer of an augmented (multilayer) state model, which is still compatible with the recursive update equation proposed originally by Kalman, the system learns directly from data all the musical notes, without labels, effectively creating a time series clustering algorithm that does not require segmentation. We analyze the HLDS properties and show that it provides better classification accuracy compared to current state-of-the-art approaches.  相似文献   
944.
Community sport organizations (CSOs) provide valuable contexts for promoting community development. These initiatives are most effective when they involve local stakeholders in the process of development. A key first step to achieving this objective is building community capacity, defined as local stakeholders’ skills, knowledge, and resources that may be leveraged for change. Interestingly, despite this conceptual importance, few researchers have focused on capacity building in the sport context. This has limited the theoretical advancement of community capacity theory as it relates to CSOs and community development. Using a qualitative case study approach, the authors analyze the outcomes and challenges of implementing community capacity building strategies in an American CSO, and draw on the empirical data to contribute to this theoretical conversation. Interviews, participant observation, and document analysis were used to generate data, and deductive techniques were used for thematic analysis. The results highlight the outcomes of the capacity building strategies and challenges associated with implementation. In addition, the conclusion focuses on theoretical contributions to community capacity theory, namely the role of sport in facilitating inter-community relations across social groups and the link with process models of organizational capacity.  相似文献   
945.
We develop and use a numerical model to investigate the window of opportunity of free kicks in association football. The planar multibody forward dynamics model comprises a two segment leg model with joint actuations, a football, a wall and the turf. Contact mechanics is defined to model the impact of the foot and the ball’s interaction with the different elements in the environment. The optimum kick is determined using the global optimization algorithm differential evolution, requiring millions of kick simulations. The sensitivity of various solutions to parameter perturbation is investigated. It is concluded that toe kicks are theoretically superior to instep kicks, but are difficult to perform reliably. The results also show that small perturbations in parameters can lead to embarrassingly failed kicks.  相似文献   
946.
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   
947.
As part of a youth summer program—a partnership between a large Southeastern university and the local school district—middle-school-aged youth, preservice teachers, and doctoral candidates interested in arts-based literacy practices spent their mornings in June 2016 engaging in activities that both explored and expanded thinking around their communities, schools, and families. Whereas the youth were enrolled in a monthlong creative arts and tentative unschooling experiment that ran roughly the length of a typical school day, university faculty and graduate students were engaged in a course on the application of youth participatory action research (YPAR). This article is an examination of the experience of preservice teachers, through an analysis of their reflections on events within the course, to suggest ways forward through the promises and perils of project-based, clinical preservice teaching experiences. In our exploration of the experiences of focal preservice teachers when engaged with youth coresearchers in a monthlong YPAR project, we found the work to have been filled with contradictions, unexpected shifts, and moments of great understanding, community affiliation, and suffering.  相似文献   
948.
This study aimed to correlate the oxidative stress marker levels in saliva with the clinical stage based on mouth opening, fibrotic bands and histopathological grades of oral submucous fibrosis (OSF) patients. The study included patients clinically diagnosed with OSF (n = 63) and equal number of age and gender matched controls. Patients with OSF were defined by mouth opening stage, fibrotic bands and histopathological grades. Unstimulated saliva from both control and OSF patients were analysed for oxidative markers like lipid peroxides (LPO), non-enzymic antioxidants [reduced glutathione (GSH), vitamin A, vitamin E, vitamin C] and enzymatic antioxidants [glutathione peroxidase (GPx), superoxide dismutase (SOD)] and correlated with different stages and grades. Total salivary protein and LPO were significantly increased in OSF group with no significant change in the levels of GSH compared to controls. In OSF patients, a significant decrease in the levels of vitamins A, C and E was observed. The activities of salivary SOD and GPx were significantly decreased in OSF patients compared to controls. These changes significantly correlated with the increasing and differing grades of OSF that reflects increased oxidative stress with the progress of OSF.  相似文献   
949.
Drought,flood,salinity,or a combination of these limits rice production.Several rice varieties are well known for their tolerance to specific abiotic stresses.We determined genetic relationship among 12 rice varieties including 9 tolerant to drought,flood,or salinity using inter-simple sequence repeat (ISSR) markers.Based on all markers,the nine tolerant varieties formed one cluster distinct from the cluster of three control varieties.The salt-tolerant varieties were closest to two flood-tolerant varieties,and together they were distinct from the drought-tolerant varieties.(GA)8 YG was the most informative primer,showing the highest polymorphic information content (PIC) and resolving power (Rp).The drought-,flood-,and salt-tolerant varieties grouped in three distinct clusters within the group of tolerant varieties,when (GA)8 YG was used.Sabita was the only exception.The two aus varieties,Nagina22 and FR13A,were separated and grouped with the drought-and flood-tolerant varieties,respectively,but they were together in dendrograms based on other primers.The results show that ISSR markers associated with (GA)8 YG delineated the three groups of stress-tolerant varieties from each other and can be used to identify genes/new alleles associated with the three abiotic stresses in rice germplasm.  相似文献   
950.
Objective: To evaluate effects of epigallocatechin-3-gallate (EGCG) on the viability, membrane properties, and zinc distribution, with and without the presence of Zn2+, in human prostate carcinoma LNCaP cells. Methods: We examined changes in cellular morphology and membrane fluidity of LNCaP cells, distribution of cellular zinc, and the incorporated portion of EGCG after treatments with EGCG, Zn2+, and EGCG+Zn2+. Results: We observed an alteration in cellular morphology and a decrease in membrane fluidity of LNCaP cells after treatment with EGCG or Zn2+. The proportion of EGCG incorporated into liposomes treated with the mixture of EGCG and Zn2+ at the ratio of 1:l was 90.57%, which was significantly higher than that treated with EGCG alone (30.33%). Electron spin resonance (ESR) studies and determination of fatty acids showed that the effects of EGCG on the membrane fluidity of LNCaP were decreased by Zn2+. EGCG accelerated the accumulation of zinc in the mitochondria and cytosol as observed by atomic absorption spectrometer. Conclusion: These results show that EGCG interacted with cell membrane,decreased the membrane fluidity of LNCaP cells, and accelerated zinc accumulation in the mitochondria and cytosol, which could be the mechanism by which EGCG inhibits proliferation of LNCaP cells. In addition, high concentrations of Zn2+ could attenuate the actions elicited by EGCG.  相似文献   
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