Exploring South Korean Elementary School Classroom Teachers' Beliefs and Practices in Physical Education.

Physical education (PE) is beneficial for the development of elementary school-age children through its promotion of different educational learning outcomes, which in turn affects the long-term development of physically active lifestyles. In many countries, PE is taught by classroom teachers (CTs), who are thought to be in a unique position to positively impact students' learning. While a substantial body of studies examines the challenges that CTs encounter when teaching PE, less research has been directed towards gaining a comprehensive understanding of how CTs visualize PE and, in turn, how to promote various types of PE. The purpose of this study, therefore, was to explore elementary school CTs' beliefs about and practices in PE in South Korea. To achieve the research goal, a semi-structured face-to face interview with six CTs was performed to collect the qualitative data source, using the ground theory as an analysis method. Three themes emerged from these interviews concerning the CTs' beliefs in PE: (a) the importance of understanding students' characteristics, (b) the importance of centering internal perceptions in PE method, and (c) the importance of meaningful experiences. The results also identified two themes for teaching practices in PE that corresponded to CTs' beliefs: (a) crafting personalized instructional methods and (b) connecting PE experiences. This study lends important insights to future practices and research recommendations for CTs' PE teaching and teacher education programs.

Head Posture and Postural Balance in Community-Dwelling Older Adults Who Use Dentures.

Background and objectives: Tooth loss and consequent denture use and impaired posture and postural balance are more prevalent in older adults than in the young ones. The aim of this cross-sectional study was to identify the association between denture use, head posture, postural balance, and neck muscle strength (NMS). Materials and methods: We included 107 participants (56 in the non-denture use group and 51 in the denture use group) and measured their NMS, forward head posture, and postural balance. Forward head posture was measured using the craniocervical angle (CRA). Postural balance was assessed using a timed up-and-go test (TUG) and postural sway. An independent t-test was used to analyze the differences between the groups; Pearson correlation analysis was used to analyze the correlation of period of denture use, head posture, and postural balance. Results: We found that the denture use group had lower NMS, smaller CRA, longer TUG, and longer postural sway length than the non-denture use group. Duration of denture use was significantly correlated with TUG. Conclusions: Our findings reveal that denture use does not help with NMS, forward head maintain NMS, head posture, and postural balance in older adults.

Brake time is correlated with lower extremity strength, dynamic balance and low-contrast sensitivity in unpredictable driving situations in elderly drivers compared with young drivers: A cross-sectional study.

AIMS: To compare physical function, driving fitness and brake time of young and elderly drivers, and to identify the association of physical function and driving fitness with brake time in elderly drivers in predictable or unpredictable situations during driving. METHODS: This study included 86 participants (50 men and 36 women), comprising 52 elderly drivers (age: 72.44 years, weight: 60.39 kg, height: 158.06 cm) and 34 young drivers (age: 26.53 years, weight: 63.74 kg, height: 153.65 cm), with a valid driver's license who drive at least once a week. Physical function was measured as upper and lower body flexibility and strength, dynamic balance and aerobic endurance. Driving fitness was measured as high- and low-contrast sensitivity, route planning, visualization of missing information, visual search with divided attention and visual information processing speed using the DrivingHealth® Inventory. Brake time and braking distance was evaluated as unpredictable and predictable driving situations. RESULTS: Measurements of all categories, except lower extremity flexibility, endurance and high-contrast sensitivity, were significantly lower in elderly drivers than in young drivers. Brake time did not differ in predictable situations but was slower (P = 0.004) in elderly drivers in unpredictable situations. In elderly drivers, upper body strength (P = 0.036), dynamic balance (P < 0.001) and low-contrast sensitivity (P = 0.003) were associated with brake time in unpredictable driving situations. CONCLUSIONS: In unpredictable situations, slower brake time in elderly drivers is associated with lower limb muscle strength, agility and low-contrast sensitivity. Therefore, for safe driving, these parameters should be considered as guidelines for maintaining the driving ability of elderly drivers and aging people. Geriatr Gerontol Int 2020; ••: ••-••.

Life lessons after classes: investigating the influence of an afterschool sport program on adolescents' life skills development.

The purpose of this study was to investigate the influence of an afterschool sport program on adolescents' life skills development and to identify which characteristics of the program would have an influence on their life skills acquisition. The participants were six children (4 boys, 2 girls) who participated in a 12-week afterschool program implemented in two elementary schools, as well as the two program instructors who implemented the afterschool sport program. Data were collected from individual interviews with program participants and instructors. The inductive analysis of data revealed four categories of life skills developed through program participation: (1) playing well and being more active, (2) connecting well and having better social skills, (3) coping well and becoming a better problem solver, and (4) dreaming well and having a better sense of purpose. Regarding the characteristics of the program that influenced life skills development, three themes emerged: (1) having a clear goal and building consensus with stakeholders, (2) establishing a firm yet flexible structure, and (3) instructors' use of effective strategies for teaching life skills.

Interparticle collision mechanism in turbulence.

Direct numerical simulations of particle-laden homogeneous isotropic turbulence are performed to investigate interparticle collisions in a wide range of Stokes numbers. Dynamics of the particles are described by Stokes drag including particle-particle interactions via hard-sphere collisions, while fluid turbulence is solved using a pseudospectral method. Particular emphasis is placed on interparticle-collision-based conditional statistics of rotation and dissipation rates of the fluid experienced by heavy particles, which provide essential information on the collision process. We also investigate the collision statistics of collision time interval and angle. Based on a Lamb vortex model for a vortex structure, we claim that collision events occur in the edge region for vortical structures in the intermediate-Stokes-number regime, suggesting that the sling effect enhances collision as well as clustering.

Inhomogeneous distribution of water droplets in cloud turbulence.

We consider sedimentation of small particles in the turbulent flow where fluid accelerations are much smaller than acceleration of gravity g. The particles are dragged by the flow by linear friction force. We demonstrate that the pair-correlation function of particles' concentration diverges with decreasing separation as a power law with negative exponent. This manifests fractal distribution of particles in space. We find that the exponent is proportional to ratio of integral of energy spectrum of turbulence times the wave number over g. The proportionality coefficient is a universal number independent of particle size. We derive the spectrum of Lyapunov exponents that describes the evolution of small patches of particles. It is demonstrated that particles separate dominantly in the horizontal plane. This provides a theory for the recently observed vertical columns formed by the particles. We confirm the predictions by direct numerical simulations of Navier-Stokes turbulence. The predictions include conditions that hold for water droplets in warm clouds thus providing a tool for the prediction of rain formation.

Comparison of postures according to sitting time with the leg crossed.

[Purpose] The purpose of this study was to identify postural changes in adults who have adopted the habit of sitting with their legs crossed. [Subjects and Methods] The subjects were 232 adults in their 20s and 30s (84 males and 148 females). They were divided into 0-, 1-, 2-, and 3-hour or more groups by observing how much time per day they sat with their legs crossed while sitting on a chair. We measured the postural alignment of all the subjects in the sagittal plane and coronal plane. In the sagittal plane, distances from the line of gravity to the external auditory meatus, the shoulder joints, the knee joints, and the calcaneocuboid joint were measured. In the coronal plane, the shoulder inclination and the pelvic tilt were measured. [Results] The shoulder joints, the knee joints, and the calcaneocuboid joint did not show any significant differences, but the head was aligned further forward in the 3-hour group compared to the other groups. In the coronal plane, the acromion processes and the anterior superior iliac spines of the 3-hour group showed statistically significant differences than those of all of the other groups. [Conclusion] The results indicate that sitting with the legs crossed for longer than three hours per day may cause shoulder inclination, lateral pelvic tilt and forward head posture.

Change of range of motion of the temporomandibular joint after correction of mild scoliosis.

[Purpose] This study aimed to verify the change in range of motion of the temporomandibular joint on correction of scoliosis. [Subjects and Methods] This study examined 31 male and female participants in their 20s and 30s with a spinal curve degree of 10° or greater. The subjects performed therapeutic exercise based on the pilates exercise system, which is known to be effective in mitigating the spinal curve for patients with scoliosis. All participants completed an 8-week therapeutic exercise regimen to alleviate the scoliosis in which exercise was performed, the exercise was done three times a week for 8 weeks and each session lasted 60 minutes. Among them, 19 participants were selected as an experiment group, whose symptoms were mitigated significantly, and 12 participants who did not undergo the exercise were identified as a control group. All subject was assessed for spinal curve degree, apparent leg length discrepancy, and deviation and range of motion of the temporomandibular joint before and after the study. [Results] In the experimental group, the apparent leg length discrepancy and the deviation of the temporomandibular joint were significantly decreased after the exercise, and the ROM in the temporomandibular joint was significantly increased. In intergroup comparisons, all variables showed a significant difference. [Conclusion] The findings suggest that as the spinal curve degree decreases significantly, the range of motion and deviation in the temporomandibular joint showed a significant change, indicating that mild scoliosis may be a negative factor affecting the deviation and range of motion of the temporomandibular joint.

Gravity-driven clustering of inertial particles in turbulence.

We report a different kind of particle clustering caused purely by gravity, discovered in our simulation of particle-laden turbulence. Clustering in a vertical strip pattern forms when strong gravity acts on heavy particles. This phenomenon is explained by the skewness of the flow velocity gradient in the gravitational direction experienced by particles, which causes horizontal convergence of particles.

The Effect of Relaxation Exercises for the Masticator Muscles on Temporomandibular Joint Dysfunction (TMD).

[Purpose] The purpose of this study was to identify the influence of relaxation exercises for the masticator muscles on the limited ROM and pain of temporomandibular joint dysfunction (TMD). [Subjects and Methods] The subjects were 10 men and 31 women in their 20s and 30s. They were randomly divided into no treatment, active exercises and relaxation exercise for the masticator muscle groups. The exercise groups performed exercises three times or more a day over a period of four weeks, performing exercise for 10 minutes each time. Before and after the four weeks, all the subjects were measured for ROM, deviation, occlusion, and pain in the temporomandibular joint. [Results] ROM, deviation and pain showed statistically significant in improvements after the intervention in the active exercise and relaxation exercise for the masticator muscle groups. Deviation also showed a statistically significant difference between the active exercise and relaxation exercise groups. [Conclusion] The results verify that as with active exercises, relaxation exercises for the masticatory muscles are an effective treatment for ROM and pain in TMD. Particularly, masticatory muscle relaxation exercises were found to be a treatment that is also effective for deviation.

The effect of the kinesio taping and spiral taping on menstrual pain and premenstrual syndrome.

[Purpose] The purpose of this study was to compare the effects of Kinesio taping and spiral taping on menstrual pain and premenstrual syndrome, to investigate the efficacy of the two types of taping as methods for alleviating menstrual pain and premenstrual syndrome. [Subjects and Methods] The subjects of this study were 34 unmarried women. The subjects were randomly divided into a Kinesio taping group, a spiral taping group and a control group. Subjects with a regular menstrual cycle underwent taping a total of six times; twice a week for about three weeks, starting from 14 days before menstruation and continuing until its end. Degrees of menstrual pain and premenstrual syndrome were measured before the application of taping. [Results] The results revealed that Kinesio taping had significant effects on menstrual pain, while spiral taping was effective at alleviating both menstrual pain and premenstrual syndrome. [Conclusion] Both taping methods before menstruation brought significant relief to menstrual pain, which suggests that spiral taping is an effective method of alleviating premenstrual symptoms.