Effects of purposeful soccer heading on circulating small extracellular vesicle concentration and cargo

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.     

Maturity model of Knowledge Management in the interpretativist perspective

Many authors have proposed categorizations for approaches to Knowledge Management; outstanding prospects including functionalist and interpretativist. In the first approach, knowledge is considered as a “static object” that exists in a number of ways and locations; in the second one, knowledge does not exist independently of human experience, social practice, of knowledge itself and its use, where it is shared by the social practices of communities, because it is “dynamic and active”. These articles constitute an extensive review on the subject, focused in reviewing, analyzing and presenting a study of the interpretativist perspective, and describe a maturity model for KM operational from it.     

Perceived effects and uses of the national teacher evaluation system in Chilean elementary schools

This paper addresses the perceived consequences of the Chilean national teacher evaluation system. We interviewed 57 school leaders in 30 schools across 10 municipalities about effects and uses of the assessment in their schools. Results show that in the large majority of schools our interviewees observe positive effects such as increased teamwork and internal reflection processes based on the assessment results. Reports about effects at teacher level far outnumber institutional effects, and are mixed. In all schools our interviewees report on teachers’ negative emotions and work overload due to the assessment process, but also about their internalization of the underlying professional standards. The paper analyzes differences among schools and offers suggestions for the development of large-scale standardized teacher evaluation systems.     

Dream Big: Exploring Empowering Processes of DREAM Act Advocacy in a Focal State

This original, qualitative research analyzed in-depth interviews with five undocumented, college-age, Latino DREAM Act advocates in a single state. An organizational empowerment framework was utilized to explore processes allied with such advocacy. Four emergent themes transcended the data inductively: (1) Challenging Social Injustice, which pertains to participant motivations for involvement; (2) Inherent Connection, which pertains to the unique personal experiences among DREAM-ers; (3) Combatting Internalized Stigma, which pertains to overcoming the shame or embarrassment of an undocumented identity; and (4) Civic Literacy, which pertains to political proficiencies that participants acquired throughout their DREAM Act involvement. Implications are discussed.     

Teacher-child relationships and the development of academic and behavioral skills during elementary school: a within- and between-child analysis

Despite recent growth in research highlighting the potential of teacher-child relationships to promote children's development during the early years of school, questions remain about the importance of these relationships across elementary school. Using data from the NICHD Study of Early Child Care (N = 1,364), this study examines between- and within-child associations between teacher-child relationship quality and children's academic achievement and behavior problems from kindergarten (ages 4-6 years) through 5th grade (ages 9-11 years). Results suggest that increases in teacher-child relationship quality are associated with improvements in teacher-reported academic skills and reductions in behavior problems consistently throughout elementary school. As children progressed from kindergarten through fifth grade, the importance of teacher-child relationship quality is unchanging.     

Researchers' attitudes and perceptions towards data sharing and data reuse in the field of food science and technology

This work analyses the perception and practice of sharing, reusing, and facilitating access to research data in the field of food science and technology. The study involved the coordination of a focus group discussion and an online survey, to understand and evince the behaviour of researchers regarding data management in that field. Both the discussion group and the survey were performed with researchers from several institutes of the Spanish National Research Council. The lack of a data sharing culture, the fear of being scooped, and confusion between the concepts of the working plan and the data management plan were some of the issues that emerged in the focus group. Respondents' previous experience with sharing their research data has been mainly in the form of appendices to peer‐reviewed publications. From the survey (101 responses), the most important motivations for publishing research data were found to be facilitating the reproducibility of the research, increasing the likelihood of citations of the article, and compliance with funding body mandates. Legal constraints, intellectual property, data ownership, data rights, potential commercial exploitation, and misuse of data were the main barriers to publishing data as open data. Citation in publications, certification, compliance with standards, and the reputation of the data providers were the most relevant factors affecting the use of other researchers' data. Being recent or recently updated, well documented, with quality metadata and ease of access were the most valued attributes of open research data.