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Eric R. Muoz Jaclyn B. Caccese Brittany E. Wilson Kyle T. Shuler Fernando V. Santos Carolina T. Cabn John J. Jeka Dianne Langford Matthew B. Hudson 《运动与健康科学(英文)》2021,10(2):122
BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease. 相似文献
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This study examined differential and mediating relations between hot and cool self-regulation (Mage = 48.2 months; N = 1,155, 48% girls), first-grade (Mage = 77.5 months) maladjustment (externalizing [EXT] and internalizing [INT] behavior), and first- and second-grade (Mage = 89.5 months) academic competence (AC). Using teacher reported EXT, INT, and AC, partial support for the differential perspective was found in that only hot self-regulation was significantly related to EXT, whereas both hot and cool self-regulation was significantly related to AC. Moreover, hot self-regulation indirectly predicted second-grade AC through first-grade EXT, lending some support for the mediating perspective also. The findings contribute to an understanding of how self-regulation is related to academic and behavioral school adjustment. 相似文献
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Supercomplexity and the university: Ronald Barnett and the social philosophy of Higher Education 下载免费PDF全文
Søren S. E. Bengtsen 《Higher Education Quarterly》2018,72(1):65-74
Ronald Barnett's modern classic Realizing the University in an Age of Supercomplexity (published December 1999), has had a crucial impact internationally on the field of Higher Education research and development since the book was published now nearly 20 years ago. Bridging an academic oeuvre across almost 30 years with close to 30 published volumes, Realizing the University in an Age of Supercomplexity plays an important role in the development and transformation of Barnett's social theory of Higher Education into a social philosophy of Higher Education. In the book Barnett performs an important move from a focus on knowledge and epistemology to a focus on being and ontology in relation to Higher Education practices. Barnett shifts his fundamental perspective and view on the relation between universities and the wider society from one of caution and worry to a perspective of hope and vision that fully embraces the future of Higher Education. This way, Realizing the University in an Age of Supercomplexity has not only paved the way for Barnett's own development of a social philosophy of Higher Education, but also contributed invaluably to the rise and maturing of philosophy of Higher Education as a research field in its own right. 相似文献
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ABSTRACT This article offers a textual analysis and semiotic reading of the Rich Kids of Tehran's (RKOT’s) Instagram page. Contributing to scholarship on Iranian youth media practices, this article interrogates how the RKOT navigate urban and rural space to engage in everyday processes of resistance against global and local systemic oppression. Grounding their visual representations on Instagram in historical and cultural context, the author questions how and when quotidian actions are transformed into political transgressions when posted on social media. This article emphasizes the RKOT's agency in shaping their brand by analyzing representations of gender performance, intertextuality, and national identity on Instagram. 相似文献
7.
Gaowei Chen Jiahong Zhang Carol K. K. Chan Sarah Michaels Lauren B. Resnick Xiaorui Huang 《British Educational Research Journal》2020,46(3):631-652
This study seeks to understand the emotional connection of teachers' academically productive talk (APT) with student learning from the students' perspective. Using a sample of 2,225 students (N7th grade = 1,146 and N8th grade = 1,079) from 16 middle schools in a city of China, we investigate the relationship between students' perceptions of their teachers’ APT, student emotions (enjoyment and anxiety) and their discursive engagement with others in the mathematics classroom. Results from structural equation modelling and mediation analysis show that after controlling for gender, family resources and mathematics achievement, student-perceived teacher APT was positively associated with their discursive engagement with classmates. Furthermore, student enjoyment and anxiety in class mediated the relationship between student-perceived teacher APT and student discursive engagement with classmates. Multi-group analysis revealed that the model was invariant across genders and grades, indicating that the associations were applicable to male and female students as well as to seventh and eighth graders. These findings shed light on the emotional relationship of teacher APT with the discursive engagement of their students. Although prior research observes a positive relationship between teacher productive classroom talk and student discursive engagement primarily through classroom observations and teacher reflections, this study provides evidence from the students’ perspective and highlights the mediating role of student emotions in the relationship. 相似文献
8.
Leg amputation side determines performance in curve sprinting: a case study on a Paralympic medalist
Johannes Funken Kai Heinrich Steffen Willwacher Ralf Müller Jonas Böcker Hiroaki Hobara 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(1):75-87
The lower limb kinetics of curve sprinting in amputees are not well described in the literature, particularly with respect to the effect of the side of amputation. This is an issue due to the importance of the knowledge for prosthetic design and classification of athletes. Thus, the aim of this study was to investigate the influence of side of amputation on curve sprinting performance in athletes with a unilateral leg amputation. A three-dimensional motion analysis system (Vicon), four force plates (Kistler) and a modified mathematical human model (ALASKA) were used to compare clockwise and counter clockwise curve sprinting lower limb kinematics and kinetics of a Paralympic medalist with a left-sided knee exarticular amputation. Results reveal that vertical ground reaction force application and total vertical impulse were lower when the affected limb was at the inside of the curve. The unaffected limb showed joint mechanics different to those established for non-amputee athletes and might contribute better to propulsion when being the inside limb. Curve sprinting biomechanics and the ability to attain high radial velocities are directly dependent on the side of amputation relative to the curve direction in a unilateral amputee athlete of highest performance level. 相似文献
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Research remains unclear on the impact of physiological load on perceptual-cognitive skills in sport. Moreover, no study has examined the training of perceptual-cognitive skills under physiological load. The current study comprised two phases. Firstly, we examined the impact of badminton-specific physiological load on anticipatory skills in expert badminton players (n = 13), including key underlying mechanisms, such as gaze behaviour. Under high physiological load, participants displayed less efficient visual search behaviour and showed a reduction in response accuracy. Secondly, we examined the effects of combining perceptual-cognitive simulation training with the high physiological load. Ten of the expert badminton players were assigned to a combined training group, where the simulation training and the physiological load intervention occurred simultaneously or an independent training group, whereby the two components were completed independently. The combined training group showed a positive change in the efficiency of their visual search behaviours compared to the independent training group, but no significant performance improvements were found. Overall, findings demonstrate that high physiological load is detrimental to experts’ anticipatory skills. However, combining perceptual-cognitive simulation training with high physiological load can potentially negate these debilitating effects. 相似文献
10.
AbstractHow should contemporary societies promote physical activity in nature and preservation of the natural environment? Outdoor life occupies a central and contested position on this question in the Nordic countries. In Norway, a 1957 Act of Parliament took a major step by guaranteeing free public access to both public and private uncultivated land. This article explores the media debate that raged in 2008–2009, when the national government proposed new legislation intended to promote outdoor life, sport, nature experience and urban forest preservation around Oslo, Norway’s capital. Applying narrative and discourse methodologies, this case study reveals how the media debate evolved from an initial cacophony of voices into a schism between advocates of nature preservation and advocates of sport. The controversy explored here is increasingly relevant throughout all of Europe: how to encourage urban active living, sustainable recreation and democratic citizenship that embody distinct social practices, identities, emotional bonds and symbolic meaning. 相似文献