263 research outputs found
Students’ Comprehension of Scientific Discussion: Using Eye-tracking Technique to Investigate the Effects of Social-media Messages on Television
The present study explores the effects of social-media messages that are presented in television content. In particular, the retention of content and changes in attitude through watching television programs was investigated. Thirty participants were randomly assigned to one of two conditions: one that included social-media messages and one that omitted social-media messages. The participants’ eye movements as well as retention performance and attitude toward the topic discussed on the television program were measured. Attitude was measured using two subscales: one concerned with positive attitude and the other with skeptical attitude. Results indicated that the retention performance of participants who paid attention to the social-media messages longer was lower than that of participants who paid less attention. The participants’ attitudes changed after watching the television program but the effects of social-media messages were unclear for attitude change. The possibility of the appropriate use of social-media messages is also discussed
ACTIVATION PATTERN OF TRUNK, THIGH AND LOWER LEG MUCLES DURING UNDERWATER DOLPHIN KICK IN SKILLED FEMALE SWIMMERS
This study investigated the muscle activation pattern between the agonist and the antagonist muscles in the trunk, thigh and lower leg during underwater dolphin kick. Thirteen female elite swimmers participated in this study and they performed 15 m underwater dolphin kick swimming at maximum effort. The surface electromyography (sEMG) of six muscles were measured and the muscle activation pattern between the agonist and antagonist muscles in the trunk, thigh and lower leg were estimated from the sEMG data. As results, the trunk and the thigh muscles showed a reciprocal activation pattern during one-kick cycle. However, the activation pattern of the lower leg muscles did not show a reciprocal pattern and it was clarified that the lower leg muscles were co-activated during the upward kick phase
Research and Development of Cooling Faraday Rotator for High Energy Laser Systems for Plasma Diagnosis and Heating
A FLOW VISUALEATION OF UNDULATORY UNDERWATER SWIMMING -A PILOT STUDY OF THREE DEIMENTIONAL AMALYSIS
The purpose of this study was to visualize the flow characteristic behind a swimmer during undulatory underwater swimming (UUS). A male college swimmer performed dolphin kicks in a water flume channel (flow velocity was set at 0.8 m+sl). By using the stereo PIV system, we captured the flow vector field in cross-sectional areas behind the swimmer and the swimmer's motions with a synchronized motion capture system. The vector fields were averaged for each kicking phase, and for spatial cross-sectional plane. This enabled visualization oft he three dimensional flow field in UUS. The results showed that the swimmer created a counter vortex pair around the feet before the downward kid, and this appeared to assist the generation of thrust during the down kick motion
〈研究資料〉Suitability of electrodes waterproofing treatment in underwater surface electromyography measurement.
THREE-DIMENSIONAL FLOW FIELD AND LEG MOTION DURING UNDULATORY UNDERWATER SWIMMING
This study described swimmers’ leg motions and the three-dimensional flow field around their legs during undulatory underwater swimming (UUS). We used the particle image velocimetry (PIV) method and a three-dimensional motion capture system. Seven male swimmers participated and we acquired EMG data of one male swimmer during UUS after the previous experiment. After the downward kick motion that includes the legs’ lateral rotation and the ankles’ dorsal flexion, water’s backward momentum was observed. During the upward kick motion, backward flow velocity decreased, but flow occurred in a vertical, upward direction. This suggested that UUS could demonstrate great propulsion power by generating jet flow through the downward kick motion that might be assisted by upstream flow from the upward kick motion
Loxoprofen Sodium, a Non-Selective NSAID, Reduces Atherosclerosis in Mice by Reducing Inflammation
Recently, it is suggested that the use of nonsteroidal anti-inflammatory drugs (NSAID) may contribute to the occurrence of cardiovascular events, while the formation of atherosclerotic lesions is related to inflammation. Loxoprofen sodium, a non-selective NSAID, becomes active after metabolism in the body and inhibits the activation of cyclooxygenase. We fed apoE−/− mice a western diet from 8 to 16 weeks of age and administered loxoprofen sodium. We measured atherosclerotic lesions at the aortic root. We examined serum levels of cholesterol and triglycerides with HPLC, platelet aggregation, and urinary prostaglandin metabolites with enzyme immune assay. Atherosclerotic lesion formation was reduced to 63.5% and 41.5% as compared to the control in male and female apoE−/− mice treated with loxoprofen sodium respectively. Urinary metabolites of prostaglandin E2, F1α, and thromboxane B2, and platelet aggregation were decreased in mice treated with loxoprofen sodium. Serum levels of cholesterol and triglycerides were not changed. We conclude that loxoprofen sodium reduced the formation of early to intermediate atherosclerotic lesions at the proximal aorta in mice mediated by an anti-inflammatory effect
エリート女性競泳選手の水中ドルフィンキックにおける体幹,大腿,下腿の筋活動様式
The purpose of this study was to clarify the pattern of muscular activity in the trunk, thigh and lower leg during the underwater dolphin kick in elite female competitive swimmers. The participants were 9 national-level competitive female swimmers who performed underwater dolphin kick swimming for 15 m at maximum effort. Sagittal movement was recorded for 2-D motion analysis, and surface electromyographic (EMG) data were recorded from 6 muscles: rectus abdominis (RA), elector spinae (ES), rectus femoris (RF), biceps femoris (BF), tibialis anterior (TA), and gastrocnemius (GAS). The EMG data were used to investigate the active phase during one kick cycle. Furthermore, the co-active phases between the agonist and the antagonist in the trunk, thigh and lower leg were evaluated in terms of estimated muscular coordination. The kinematic results indicated that the average swimming velocity and the strouhal number for these swimmers were similar to those for Olympic swimmers in a previous study. Furthermore, a whiplash-like action was observed in their underwater dolphin kick movement. The EMG results indicated that the active phases of all subjective muscles during one kick cycle were approximately 60%. Co-active phases were observed in all pairs (RA-ES: 24.1±10.1%, RF-BF: 23.2±5.5%, TA-GAS: 45.5±20.2%), and the co-active phase of TA-GAS was significantly larger than for the other pairs (p<0.05). From these results, two main findings emerged with regard to the muscular activity pattern during the underwater dolphin kick in elite female competitive swimmers: (1) the muscular activity patterns in the trunk and thigh muscles were reciprocal; (2) the co-active phase for the lower leg muscles was larger than for the other parts and occurred during the first half of the upward kick phase
多段階の泳速度におけるクロール泳中の自己推進時抵抗とストリームライン姿勢中の受動抵抗の比較
The purpose of this study was to compare active drag during front-crawl swimming performed by competitive swimmers with passive drag acting on the same group of swimmers with a streamlined position at various velocities. Seven male competitive swimmers participated in this study, and the testing was conducted in a swimming flume. Active drag was evaluated for front-crawl swimming with upper and lower limb motion using a methodology that estimates the drag in swimming using measured residual thrust values (MRT method). Passive drag was measured by a load cell connected to the swimmers with a streamlined position using a stainless-steel wire. In each case, drag was estimated at six staged velocities ranging from 1.0 to 1.5 m/s. To compare the drags at various velocities, we calculated coefficients a and b by applying the measured force value at each velocity to the equation D = a vb (D: drag, v: velocity). The active drag estimated from the MRT method (a = 35.7 ± 5.3, b = 2.80 ± 0.22) was larger than passive drag (a = 23.6 ± 3.1, b = 2.08 ± 0.23). Furthermore, the difference between active and passive drag was large at high velocities. Therefore, it is possible that the effects of factors other than posture and/or body shape have a large influence on active drag, especially at high velocity
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