Modification of human high density lipoprotein by cigarette smoke extract and its impact on reverse cholesterol transport

High density lipoprotein (HDL) normally functions with lecithin:cholesterol acyltransferase (LCAT) to facilitate reverse cholesterol transport whereby excess cholesterol is removed from peripheral tissue sites, such as arteries. Cigarette smoke contains reactive chemicals which may modify HDL and, therefore, impair its antiatherogenic function in reverse cholesterol transport. We tested this hypothesis by first comparing modification of HDL by cigarette smoke extract (CSE) and acrolein, a potent reactive aldehyde known to be present in cigarette smoke. Both CSE and acrolein caused structural modification of HDL in a concentration-dependent manner, as evidenced by diminution of free amino groups, increase in electrophoretic mobility, and apolipoprotein crosslinking. We then evaluated the capacity of modified HDL to activate LCAT, which requires apolipoprotein A-1 as a cofactor, and also to stimulate cholesterol efflux from THP-1 monocytic cells

Elementary school students’ naïve conceptions and misconceptions about energy in physical education context

The purpose of this study was to explore and reveal naïve conceptions and misconceptions about energy embedded in elementary school students’ prior knowledge. Students’ performance on standardized knowledge test was used to classify students into low, median and high levels of knowledge about the cardiovascular system. Semi-structured in-depth interviews were conducted with students in each group to extract their understanding of energy in relation to food choices, physical activities, and exercises. Analysis of the interview data generated six categories of naïve conceptions and two categories of misconceptions. Different conceptual change theories, including Chi’s ontological change theory, Ohlsson’s resubsumption theory, and enculturation theory were used to analyze and understand these naïve conceptions and misconceptions and why they could be robust to change. The analyses confirm the need to adopt a multi-theoretical approach to the understanding of students’ naïve conceptions and misconceptions (Chinn & Samarapungavan, 2009. Conceptual change-multiple routes, multiple mechanisms: A commentary on Ohlsson. Educational Psychologist, 44(1), 1–10). The findings encourage physical and health educators adopt different strategies to address the potential learning obstacles brought by students’ naïve conceptions and misconceptions

Situational interest, cognitive engagement, and achievement in physical education

Students’ learning has been the center of schooling. This study examined the contribution of situational interest motivation and cognitive engagement in workbooks to student achievement in learning health-related fitness knowledge. Situational interest, performance on solving workbook problems, and knowledge gain in cardio-respiratory fitness and benefits were measured in 670 third-grade students from 13 randomly selected urban elementary schools. Structural equation modeling and regression curve estimation analyses revealed that situational interest contributed little to workbook performance and knowledge gain. Performance on solving workbook problems contributed significantly to knowledge gain. The results also show that skipping workbook tasks had stronger negative impact on knowledge gain than performing the tasks incorrectly, suggesting the importance of engaging students in the learning process by attempting the workbook tasks. The findings reinforced the value of using workbooks to facilitate cognitive knowledge learning in physical education, but raised questions about the direct function of situational interest on engaging students in cognitive learning

Ninth graders’ learning differences in a healthful-living curriculum

Physical education and health education are relevant avenues for adolescents to learn knowledge and behavior related to energy-balanced living. Grounded in the framework theory of conceptual change, this study examined ninth graders' energy balance knowledge (i.e., concepts, principles, and strategies underlying the scientific mechanism and the outcome of energy balanced/imbalanced living) and physical activity in a healthful-living curriculum (i.e. combination of physical education and health). The students (N = 195) were measured using concept mapping, accelerometers, and three-day physical activity recall. It was found that the students differed in energy balance knowledge where most (83%) lacked a higher-order relational understanding. Physical activity in physical education class or after school did not significantly differ by students' mental model levels concerning energy balance knowledge. The findings suggest that an ecological learning context with moderate physical activity should be provided to help students make sense of energy balance knowledge through lived experiences

Remembering Cathy Ennis: The mentor

I worked with Cathy for 28 years. She was my mentor of doctoral studies and my colleague at the University of Maryland–College Park and University of North Carolina at Greensboro (UNCG). I can attest that all of her students share the same sentiment: Cathy has changed our lives for the good. As one of our students said, “I would not be where I am today without Dr. Ennis.” Cathy was, and continues to be, the greatest inspiration for us. We remember her as a demanding professor, but also as a sister and a “mother figure” who cared for her “children” all the time, even during the last week of her life

Task Values, Cost, and Choice Decisions in College Physical Education

The expectancy-value motivation theory postulates that motivation can be achieved when perceived values in an activity override perceived cost of the activity derived from the effort of achieving. This study was designed to examine types of perceived cost in physical education and the extent to which the cost might affect motivation. Data about attainment, intrinsic, and utility values in physical education were collected using surveys from college students (n = 368) in China. Perceived cost was investigated through open-ended written responses and interviews. Disappointment about the curriculum emerged as a major cost to motivation and lack of student autonomy was identified as a direct demotivating factor. Despite the cost, most of the students (92%) indicated they would, if given a choice, elect to continue physical education for health benefits and broader motivational impact in life, suggesting that strong positive values of physical activity might override the impact of cost. The findings suggest the importance of emphasizing positive values of physical activity in physical education

Interactive Impact of Intrinsic Motivators and Extrinsic Rewards on Behavior and Motivation Outcomes

In this study we examined the interrelationship among extrinsic rewards and achievement goals (including a work-avoidance goal), competence beliefs, and task values associated with health-enhancing running tasks over a school year. A group of elementary school students (n = 119) from a program that promoted running for running’s sake and another (n = 88) from a program that promoted running through games provided pre- and post-year data on students’achievement goals, competence beliefs, task values, achievement in running tests, and future intention to continue running as a health-enhancing activity. Results showed that students in the running-for-games program demonstrated significant growth in task-involved achievement goals. The regression analyses showed that extrinsic reward and selected intrinsic motivation constructs played a small role in predicting running-test scores. Interest, however, emerged as the most important intrinsic motivation construct for predicting future motivation for running. Interest seemed to override the effects not only of extrinsic reward but also of other intrinsic motivation sources. This finding suggests that interest-based motivation sources might have a strong and prolonged effect on learner motivation

Gender, BMI, values, and learning in physical education: A study on Chinese middle schoolers

Students' different perceptions of task values influence their learning experience and achievement in physical education. Framed using the subjective task value construct, this study was conducted to determine the extent to which male and female Chinese middle schoolers with different body sizes differed in their perception of the task values. A second goal of the study was to identify the extent to which the task values along with gender and body size predicted students' performance on knowledge and physical skill tests. Data from a random sample of students (N = 860) from eight Chinese middle schools revealed that the boys appreciated intrinsic (p = .001) and utility values (p = 02); both boys and girls, however, equally appreciated the attainment value (p = .73). The boys performed better in physical skill tests than the girls (p = .001), whereas the girls scored higher in knowledge tests than the boys (p = .04). Regression analyses revealed that gender is the only predictor for performance on both knowledge and skill tests. Utility value and body size were predictors for skill, not for knowledge. These findings indicate that Chinese middle school boys and girls differed in valuing and achieving in physical education. The findings imply that Chinese boys need to strengthen cognitive learning and girls need to strengthen psychomotor skill development in physical education

Physical activity and fitness knowledge learning in physical education: Seeking a common ground

Motivation to learn is a disposition developed through exposure to learning opportunities. Guided by the expectancy-value theory of Eccles and Wigfield (1995), this study examined the extent to which expectancy belief and task value influenced elementary school students’ physical activity and knowledge learning in physical education (PE). Students (N = 753) from 15 US public schools contributed student-level and class-level data. With a 2-level design, the data were analyzed using hierarchical linear modeling. Physical activity (t = 3.18; p < .01) positively predicted fitness knowledge. Attainment value (i.e. perception of importance) as the only expectancy-value construct, significantly predicted fitness knowledge (t = 3.07; p < .01), when physical activity was held constant. As the physical activity intensity increased, the positive prediction of attainment value to knowledge attenuated and then turned negative (t = –3.10; p < .01). The study indicated that although a physically-active context helps students to make sense of fitness knowledge, a vigorous context shifts their motivation away from cognitive learning, toward physical participation. To resolve the difficulty of attaining learning objectives both physically and cognitively, PE teachers may want to maintain an active learning context with moderate physical intensity. Future research should address the effect of learner motivation on dual or multiple learning outcomes in PE