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61.
This introductory article to the combined special issue of Journalism Studies and Journalism Practice provides an overview of some of the key contemporary approaches to studying journalism and social order. It argues the need to step beyond a functionalist framework when considering the news media’s central role in shaping social connections, community and cohesion. To advance our understandings of social order, our paper suggests a greater emphasis of the significance of journalism’s relationship to the wider social sphere along with three other key considerations, including (1) a critical focus on the relationship between media, politics and social order, especially in defining and/or negotiating “anti-social” practices and social disintegration; (2) a more refined focus on the “imagined” and geographic boundaries of news audiences in digital spaces; and (3) the changing relationship to norms and conventions of journalism practice from trust and legitimacy to the role of journalists as arbiters and connectors across social spaces. 相似文献
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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):122-130
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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Eisenhauer ER Mosher EC Lamson KS Wolf HA Schwartz DG 《Health information and libraries journal》2012,29(2):152-161
Background: Somali Bantu refugees, with unique health information needs, created challenges for health and social service providers. Objectives: A service innovation was developed (i) to raise awareness, especially among local health and social service providers, about the Bantu refugees’ presence in the community, their culture, and their information needs and (ii) to deliver needed health information, emphasizing child health, to the Bantu mothers in their homes. Methods: The project consisted of: (i) a community conference targeting local health and social service providers, describing the refugees’ presence in the community, their culture, and information needs. (ii) Focus groups conducted with members of the Bantu population elicited additional information needs. (iii) Curriculum was developed based on identified needs, and (iv) the curriculum was delivered to the refugees in their homes. A clinical informationist and MP3 technology enhanced the project. Findings: Conference attendees’ evaluation responses indicated improved understanding of Bantu culture. Focus groups’ identification of health information needs provided a framework for the health education curriculum. A project website made educational materials available to other healthcare providers. Conclusions: The project raised awareness of the Bantus’ presence, culture, and information needs. Identification of other unmet needs demonstrated that additional support for refugees is required. 相似文献
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The relationship between peak height velocity and physical performance in youth soccer players 总被引:1,自引:1,他引:0
Philippaerts RM Vaeyens R Janssens M Van Renterghem B Matthys D Craen R Bourgois J Vrijens J Beunen G Malina RM 《Journal of sports sciences》2006,24(3):221-230
Longitudinal changes in height, weight and physical performance were studied in 33 Flemish male youth soccer players from the Ghent Youth Soccer Project. The players' ages at the start of the study ranged from 10.4 to 13.7 years, with a mean age of 12.2 +/- 0.7 years. Longitudinal changes were studied over a 5 year period. Peak height velocity and peak weight velocity were determined using non-smoothed polynomials. The estimations of peak height velocity, peak weight velocity and age at peak height velocity were 9.7 +/- 1.5 cm x year-1, 8.4 +/- 3.0 kg x year-1 and 13.8 +/- 0.8 years, respectively. Peak weight velocity occurred, on average, at the same age as peak height velocity. Balance, speed of limb movement, trunk strength, upper-body muscular endurance, explosive strength, running speed and agility, cardiorespiratory endurance and anaerobic capacity showed peak development at peak height velocity. A plateau in the velocity curves was observed after peak height velocity for upper-body muscular endurance, explosive strength and running speed. Flexibility exhibited peak development during the tear after peak height velocity. Trainers and coaches should be aware of the individual characteristics of the adolescent growth spurt and the training load should also be individualized at this time. 相似文献
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Based on ideas from subjective uncertainty reduction theory, we examined the extent to which individuals hold similar sport team preferences to their family and friends. We also assessed the extent to which perceived sport importance and personal need for structure are influential in the development of team identification. Australian high school students aged 15.5+/-1.0 years (mean+/-s) completed questionnaires containing the Personal Need for Structure Scale, the Relational-Interdependent Self-Construal scale, a Team Identification Scale, and items assessing perceptions of sport importance and team preferences. As expected, correlations indicated that preferences for sport teams were significantly related to the preferences of family and friends. Separate analyses of variance confirmed the remaining hypotheses. More specifically, individuals who perceived that sport was important identified with the team more than individuals who perceived sport to be less important. Also, individuals high in personal need for structure scored higher in cognitive/affective team identification than those low in this need. Individuals with differing needs for structure did not differ in their scores on other dimensions of team identification. The results support the notion that cognitive/emotional attachments to sport teams are influenced by perceptions of the importance of sport and by needs for subjective structure. It is possible that other psychological motives, such as the desire for self-esteem, facilitate the development of evaluative dimensions of team identification. 相似文献
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R.C. Rosenberg 《Journal of The Franklin Institute》1979,308(3):343-352
This paper proposes an extended definition of reciprocity for a multiport junction structure based on the concept of essential gyrator coupling. Two theorems are given for junction structures containing gyrators and an algorithm is presented for identifying essential gyrators. The results are useful both theoretically and for designing efficient computation procedures for junction structures. 相似文献