排序方式： 共有23条查询结果，搜索用时 15 毫秒
1.
Kohei Watanabe Takayuki Sato Takahiro Mukaimoto Wataru Takashima Michio Yamagishi Tetsunari Nishiyama 《Journal of sports sciences》2016,34(15):1413-1422
We aimed to investigate neuromuscular activation of thigh muscles during track cycling at various speeds. Eight male competitive cyclists volunteered to participate in this study. Surface electromyography of the vastus lateralis, biceps femoris and adductor magnus muscles of the bilateral legs was recorded during track cycling on velodromes with a 250-m track. The participants were instructed to maintain three different lap times: 20, 18 and 16 s. The average rectified value (ARV) was calculated from the sampled surface electromyography. Significantly higher ARVs were observed in the right compared to left leg for the biceps femoris muscle during both straight and curved sections at 18- and 16-s lap times (P < 0.05). In the biceps femoris muscle, significant changes in ARVs during the recovery phase with an increase in speed were seen in the right leg only (P < 0.05). There were no significant differences in ARVs between the straight and curved sections for all three muscles (P > 0.05). From our findings, it was suggested that during track cycling on a velodrome the laterality of the biceps femoris muscle activity is a key strategy to regulate the speed, and fixed neuromuscular strategies are adopted between straight and curved sections for thigh muscles. 相似文献
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SYNOPSISObjective: Infant cry, a major stressor for caregivers, is one of the leading triggers of child abuse. The present study examined the effects of spousal support, spousal presence, and the possible moderating effect of attachment insecurity on individuals’ subjective and physiological responses to infant cry. Design: Thirty-one healthy mothers (M age = 36 years) and their spouses participated in an infant crying paradigm, where mothers were tasked to listen to infant cries under three conditions: (1) alone, (2) in the same room as partner, without physical contact, and (3) in the same room as partner, with hand-holding. Attachment was determined using the Experiences in Close Relationship Questionnaire, and physiological response was ascertained from concentration of salivary α-amylase (sAA). After each cry sound, sAA level and subjective responses to infant cry were assessed. Results: Multilevel regression analyses revealed that trait attachment-anxiety moderated the effect of spousal presence on sAA. Specifically, mothers with high attachment-anxiety showed reduced sAA when their spouse was present, which indicates that spousal support is effective for mothers with high attachment-anxiety. Conclusions: Findings from this study translate to promising clinical applications for the management of parenting stress from infant cry. 相似文献
3.
Naoyuki Takeuchi Takayuki Mori Yoshimi Suzukamo Shin‐Ichi Izumi 《Mind, Brain, and Education》2019,13(3):167-175
Metacognitive functions are important for both teachers and students to facilitate teaching and learning. The prefrontal cortex (PFC) plays a proven role in metacognition. As a pilot study, we evaluated the PFC activity of teachers and students using near‐infrared spectroscopy devices to explore the neural mechanism of PFC underlying metacognitive function during teaching and problem‐solving processes. In 14 student‐teacher pairs, participants in the teacher role gave hints via a tablet screen to facilitate solving of a tangram puzzle task by participants in the student role. The PFC activity of teachers increased after giving hints but not while planning hints. The PFC activity of students increased upon task solving after receiving hints. The PFC of teachers might play a metacognitive role in monitoring their own teaching results. The PFC activity of students might be related to the creativity process after gaining insights, as well as metacognitive process for monitoring their own behavior. 相似文献
4.
Miwa A. Takeuchi Pratim Sengupta Marie-Claire Shanahan Jennifer D. Adams Maryam Hachem 《Studies in Science Education》2020,56(2):213-253
ABSTRACT Science, Technology, Engineering and Mathematics (STEM) education garnered significant attention in recent years and has emerged as a key field of research globally. The goal of this article is to offer a critical review of how STEM education and its transdisciplinarity were defined and/or positioned in empirical studies published during the early formulation of the field. In particular, we sought to identify how these studies conceptualise learners and learning and portray the underlying assumptions in light of the macrosystemic discourses that often serve as ideological forces in shaping research and practice of STEM education. We examined 154 peer-reviewed articles published between January 2007 and March 2018 and analysed them along several emergent dimensions: their geospatial focus, focal disciplinary areas, methodological and theoretical assumptions, and major findings. Grounded in a critical transdisciplinary perspective, we used critical discourse analysis to identify how macrosystemic and institutionalised forces – overtly and implicitly – shape what counts as STEM education research, including its goals and conceptualisations of learners and learning. Our analysis highlights the need for aesthetic expansion and diversification of STEM education research by challenging the disciplinary hegemonies and calls for reorienting the focus away from human capital discourse. 相似文献
5.
Sarah Nur Marshall Kendall J. Michio Clark T. Blaine Hoshizaki 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):459-469
Goaltenders in ice hockey are the only players that are on the ice for the entire game. Their position exposes them to impacts from collisions with other players, falls to the ice, and puck impacts. In competitive ice hockey leagues, head injuries resulting from puck impacts have been reported with some cases resulting in ending the player’s career. Considerable research has been conducted to assess the performance of hockey helmets; however, few have assessed the performance of goaltenders’ masks. The purpose of this study was to compare the capacity of four goaltenders’ masks for the protection from puck impact as measured by head acceleration and peak force. A Hybrid III headform was fitted with four different goaltender masks and impacted with a hockey puck in three locations at 25 m/s. The masks were found to vary in the level of protection they offered as the mask with the thickest liner resulted in lower forces than the thinnest mask for side impacts; however, the thinnest mask resulted in the lowest force for front impacts. Despite performance differences at specific locations, no one mask proved to be superior as peak acceleration and peak force values did not exceed the thresholds necessary for concussion. 相似文献
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Andrew Post J. Michio Clark D. G. E. Robertson T. Blaine Hoshizaki Michael D. Gilchrist 《Sports Engineering》2017,20(2):111-119
Brain injury research in sport employs a variety of physical models equipped with accelerometers. These acceleration signals are commonly processed using filters. The purpose of this research was to determine the effect of applying filters with different cutoff frequencies to the acceleration signals used as input for finite element modeling of the brain. Signals were generated from reconstructions of concussion events from American football and ice hockey in the laboratory using a Hybrid III headform. The resulting acceleration signals were used as input for the University College Dublin Brain Trauma Model after being processed with filters. The results indicated that using a filter with a cutoff of 300 Hz or higher had little effect on the resulting strain measures. In some cases there was some effect of the filters on the peak linear (8–30g) and rotational measures (1000–4000 rad/s2), but little effect on the finite element strain result (approximately 2–6 %). The short duration and high magnitude accelerations, such as the puck impact, were most affected by the cutoff frequency of different filters. 相似文献
8.
This study investigated the variations of perspectives of junior high school students who had participated in Smartphone Summit for appropriate usage of the Internet and smartphones. Smartphone Summit is an educational project designed to empower junior high school students to advocate appropriate usage of the Internet and smartphones among older, same-age, and younger peers, within school communities and society as a whole. The participants were 26 students (7th and 8th grade) from 18 junior high schools in Okayama, a western Japanese city. In the project, the participants discussed pros and cons of the Internet and smartphones, and presented their ideas concerning possible activities to encourage their classmates to use the Internet and smartphones in appropriate ways with the help of various adult experts. A questionnaire was administered to measure the participants’ evaluation of their own and their classmates’ present smartphone usage as well as anticipated future smartphone usage. Results showed that the participants evaluated their own usage as more appropriate than that of their classmates and expected that future usage would be better for both themselves and their classmates than at present. Furthermore, the participants expected their classmates’ usage will change more significantly than their own because their classmates’ current usage seems relatively inappropriate and there would be larger room for improvement. From the analysis of patterns of participants’ impact expectation toward their peers, it was found that there were three types of perspectives: moderate, relatively lower, and relatively higher evaluation. Future research should focus on the factors influencing the participants’ perspectives. 相似文献
9.
Kobayashi Y Takeuchi T Hosoi T Yoshizaki H Loeppky JA 《Research quarterly for exercise and sport》2005,76(4):450-455
The objective of this study was to determine the effect of a marathon run on serum lipid and lipoprotein concentrations and serum muscle enzyme activities and follow their recovery after the run. These blood concentrations were measured before, immediately after, and serially after a marathon run in 15 male recreational runners. The triglyceride level was significantly elevated postrace, then fell 30% below baseline 1 day after the run, and returned to baseline after 1 week. Total cholesterol responded less dramatically but with a similar pattern. High-density lipoprotein cholesterol remained significantly elevated and low-density lipoprotein cholesterol was transiently reduced for 3 days after the run. The total cholesterol/high-density cholesterol ratio was significantly lowered for 3 days. Serum lactate dehydrogenase activity significantly doubled postrace and then declined but remained elevated for 2 weeks. Serum creatine kinase activity peaked 24 hr after the run, with a 15-fold rise, and returned to baseline after 1 week. The rise of these enzymes reflects mechanically damaged muscle cells leaking contents into the interstitial fluid. It is concluded that a prolonged strenuous exercise bout in recreational runners, such as a marathon, produces beneficial changes in lipid blood profiles that are significant for only 3 days. However, muscle damage is also evident for 1 week or more from the dramatic and long-lasting effect on enzyme levels. Laboratory values for these runners were outside normal ranges for some days after the race. 相似文献
10.
Orloff ND Dennis JR Cecchini M Schonbrun E Rocas E Wang Y Novotny D Simmonds RW Moreland J Takeuchi I Booth JC 《Biomicrofluidics》2011,5(4):44107-441079
We present a 91 MHz surface acoustic wave resonator with integrated microfluidics that includes a flow focus, an expansion region, and a binning region in order to manipulate particle trajectories. We demonstrate the ability to change the position of the acoustic nodes by varying the electronic phase of one of the transducers relative to the other in a pseudo-static manner. The measurements were performed at room temperature with 3 μm diameter latex beads dispersed in a water-based solution. We demonstrate the dependence of nodal position on pseudo-static phase and show simultaneous control of 9 bead streams with spatial control of −0.058 μm/deg ± 0.001 μm/deg. As a consequence of changing the position of bead streams perpendicular to their flow direction, we also show that the integrated acoustic-microfluidic device can be used to change the trajectory of a bead stream towards a selected bin with an angular control of 0.008 deg/deg ± 0.000(2) deg/deg. 相似文献