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91.
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
92.
Matthew J. Madison 《Educational Measurement》2019,38(2):68-78
Recent advances have enabled diagnostic classification models (DCMs) to accommodate longitudinal data. These longitudinal DCMs were developed to study how examinees change, or transition, between different attribute mastery statuses over time. This study examines using longitudinal DCMs as an approach to assessing growth and serves three purposes: (1) to define and evaluate two reliability measures to be used in the application of longitudinal DCMs; (2) through simulation, demonstrate that longitudinal DCM growth estimates have increased reliability compared to longitudinal item response theory models; and (3) through an empirical analysis, illustrate the practical and interpretive benefits of longitudinal DCMs. A discussion describes how longitudinal DCMs can be used as practical and reliable psychometric models when categorical and criterion‐referenced interpretations of growth are desired. 相似文献
93.
Matthew B. Rhudy Scott B. Dreisbach Matthew D. Moran Marissa J. Ruggiero Praveen Veerabhadrappa 《Journal of sports sciences》2020,38(5):503-510
ABSTRACTAccelerometer cut points are an important consideration for distinguishing the intensity of activity into categories such as moderate and vigorous. It is well-established in the literature that these cut points depend on a variety of factors, including age group, device, and wear location. The Actigraph GT9X is a newer model accelerometer that is used for physical activity research, but existing cut points for this device are limited since it is a newer device. Furthermore, there is not existing data on cut points for the GT9X at the ankle or foot locations, which offers some potential benefit for activities that do not involve arm and/or core motion. A total of N = 44 adults completed a four-stage treadmill protocol while wearing Actigraph GT9X sensors at four different locations: foot, ankle, wrist, and hip. Metabolic Equivalent of Task (MET) levels assessed by indirect calorimetry along with Receiver Operating Characteristic (ROC) curves were used to establish cut points for moderate and vigorous intensity for each wear location of the GT9X. Area under the ROC curves indicated high discrimination accuracy for each case. 相似文献
94.
ABSTRACTWithin the context of Pintrich’s self-regulated learning model, recent reviews of the literature show that motivational factors are the strongest predictors of academic performance. Even so, gaps remain in terms of which goal orientation constructs area most strongly related to performance, and whether academic self-efficacy is involved in such relationships, either as mediator or moderator. This study addresses these gaps using a sample of 478 university students; 409 females aged 17–62 (M?=?23.28, SD?=?7.22) and 69 males, aged 18–47 (M?=?22.5, SD?=?6.31). Analyses revealed that academic self-efficacy (ASE) mediated relationships between both mastery and performance-approach goal orientation with achievement, though the mediation effect was larger for the relationship involving mastery approach goal orientation. ASE did not moderate the relationship between performance-approach goal orientation and achievement. Findings suggest teaching programmes should foster learning environments that encourage persistence and effort when learning, and consider how course delivery and feedback can enhance academic self-efficacy, regardless of the goal orientation adopted by students. 相似文献
95.
Matthew B. Hoy 《Medical reference services quarterly》2017,36(3):273-279
The blockchain is a relatively new technology used to verify and store transaction records for online cryptocurrencies like Bitcoin. The system is redundant and distributed, making it difficult for transactions to be rescinded, duplicated, or faked. Beyond online currencies, the blockchain has potential uses in health care, education, and many other fields. This column will briefly describe what the blockchain is and how it is being used, potential future uses that may be of interest to librarians and medical practitioners, and some of the problems with the system. 相似文献
96.
Bobby Hoffman Matthew T. McCrudden Gregory Schraw Kendall Hartley 《Asia Pacific Education Review》2008,9(4):464-474
This study investigated the influence of informational complexity and working memory capacity on problem-solving efficiency.
We examined two predictions of thesituational efficiency hypothesis, which states that the efficiency of problem solving varies as a function of situational constraints. One prediction is that
informational complexity affects problem-solving efficiency. A second prediction is that working memory capacity affects problem-solving
efficiency. Students completed a working memory task and solved abstract and concrete syllogisms. Participants solved abstract
syllogisms more accurately than concrete syllogisms and spent more time solving abstract syllogisms. Thus participants demonstrated
greater problem-solving efficiency when solving concrete syllogisms. Results indicate that there is a trade-off between problem-solving
accuracy and problem-solving time when information differs with respect to informational complexity, a phenomenon we refer
to as theefficiency paradox. Working memory capacity did not affect accuracy or efficiency. The results support the conclusion that problem-solving efficiency
is situational and a function of the complexity of information. Educational implications and directions for future research
are suggested. 相似文献
97.
98.
Matthew Weinstein 《Science & Education》2008,17(8-9):961-975
With an eye towards a potential scientific ethics curriculum, this paper examines four contrasting discourses regarding the ethics of using human subjects in science. The first two represent official statements regarding ethics. These include the U.S.’s National Science Education Standards, that identify ethics with a professional code, and the Belmont Report, that conceptualizes ethics in three principles to guide research oversight boards. Contrasting this view of ethics as decorum and practice in line with a priori principles is the conception of ethics from unofficial sources representing populations who have been human subjects. The first counter-discourse examined comes from Guinea Pig Zero, an underground magazine for professional human subjects. Here ethics emerges as a question of politics over principle. The good behavior of the doctors and researchers is an effect of the politics and agency of the communities that supply science with subjects. The second counter-discourse is a comic book called Truth, which tells the story of Black soldiers who were used as guinea pigs in World War II. Ethics is both more political and more uncertain in this narrative. Science is portrayed as complicit with the racism of NAZI Germany; at the same time, and in contrast to the professional guinea pigs, neither agency nor politics are presented as effective tools for forcing the ethical conduct of the scientific establishment. The conclusion examines the value of presenting all of these views of scientific ethics in science education. 相似文献
99.
Effect of acquisition rates on off‐task behavior of kindergarten students while learning sight words
Matthew K. Burns Lisa N. Aguilar Kristy Warmbold‐Brann June L. Preast Crystal N. Taylor 《Psychology in the schools》2021,58(1):5-17
Assessing a student's acquisition rates (ARs) is a reliable way to determine how many new words should be taught in one lesson without reducing retention. Exceeding a student's AR can result in frustration and problem behaviors. The purpose of this study was to examine the effect of AR on the off‐task behavior of kindergarten students while participating in a commonly used sight‐word instruction video. Participants included 39 kindergarten students whose ARs were assessed before showing the sight‐word video. Behavior was measured as on‐ and off‐task using momentary time‐sampling with 10‐s intervals. Results indicated that students' time off task increased after exceeding their ARs, with a noticeable immediate increase. The implications and limitations of these results are discussed. 相似文献
100.
Research in Higher Education - Integrative learning is the ability to connect, apply, and/or synthesize. A highly valued skill for the knowledge economy and combating false narratives, integrative... 相似文献