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61.
62.
Erythropoietin concentration and arterial haemoglobin saturation with supramaximal exercise. 总被引:3,自引:0,他引:3
The aim of this study was to determine if the hypoxaemic stimulus generated by intense exercise results in the physiological response of increased erythropoietin production. Twenty athletes exercised for 3 min at 109 +/- 2.8% (mean +/- s) maximal oxygen consumption. Estimated oxyhaemoglobin saturation was measured by reflective probe pulse oximetry (Nellcor N200) and was validated against arterial oxyhaemoglobin saturation by CO-oximetry in eight athletes. Serum erythropoietin concentrations-as measured using the INCSTAR Epo-Trac radioimmunoassay-increased significantly by 28 +/- 9% at 24 h post-exercise in 11 participants, who also had an arterial oxyhaemoglobin saturation < or = 91% (P < 0.05). Decreased ferritin levels and increased reticulocyte counts were observed at 96 h post-exercise. However, no significant changes in erythropoietin levels were observed in nine non-desaturating athletes and eight non-exercise controls. Good agreement was shown between arterial oxyhaemoglobin saturation and percent estimated oxyhaemoglobin saturation (limits of agreement = -3.9 to 3.7%). In conclusion, short supramaximal exercise can induce both hypoxaemia and increased erythropoietin levels in well-trained individuals. The decline of arterial hypoxaemia levels below 91% during exercise appears to be necessary for the exercise-induced elevation of serum erythropoietin levels. Furthermore, reflective probe pulse oximetry was found to be a valid predictor of percent arterial oxyhaemoglobin saturation during supramaximal exercise when percent estimated oxyhaemoglobin saturation > or = 86%. 相似文献
63.
Richard B. Fletcher Margaret H. Roberts 《Measurement in physical education and exercise science》2013,17(2):89-104
This study was designed to examine the role of foot type, height, leg length, and range of motion (ROM) measurements on excursion distances while performing the Star Excursion Balance Test (SEBT), a test of dynamic postural control. Participants (n = 30) performed 3 trials of the SEBT in each of the 8 directions while balancing on the right and left legs. No statistically significant relations were found between foot type or ROM measurements and excursion distances with the SEBT. Significant correlations were revealed between height and excursion distance and leg length and excursion distance with leg length having the stronger correlation. Using raw excursion measures, males were found to have significantly greater excursion distances than females; however, after normalizing excursion distances to leg length, there were no significant differences related to gender. In conclusion, when using the SEBT for experimental or clinical purposes, participants' excursion distances should be normalized to leg length to allow for a more accurate comparison of performance among participants. 相似文献
64.
The present experiment examined the learning effects of participants self-controlling their receipt of knowledge of results (KR) on all or half of their acquisition trials (50%). For participants who were provided 50% self-control, the first half of their acquisition period consisted of receiving KR on all trials, or according to a faded-KR schedule. Participants practiced a sequential timing task. The results showed that independent of practice condition, participants who self-controlled their KR during the acquisition period demonstrated superior performance compared to the respective yoked conditions in the retention and transfer portion of the experiment. These results extend previous research by suggesting that decreasing the proportion of self-control trials does not compromise learning in a self-controlled context. 相似文献
65.
Stephen P. Messier Mary Elizabeth Dill 《Research quarterly for exercise and sport》2013,84(4):345-351
Abstract The purpose of this study was to determine the effects of a Nautilus circuit weight training program on muscular strength and maximal oxygen uptake ([Vdot]O 2 max) by comparing these effects to those produced by adhering to either a free weight (FW) strength training program or a running (R) program. Male college students who voluntarily enrolled in either a FW training class (n = 11), a Nautilus (N) circuit weight training class (n= 12), or a R conditioning class (n= 13) were subjects for this investigation. All groups participated in their respective programs 3 days per week for 10 weeks. Strength was assessed using a Cybex II isokinetic dynamometer set at an angular velocity of 60° · s ?1 and a damping of 2. The FW group served as the control group for the assessment of [Vdot]O 2 max changes, while the R group served as controls for the assessment of strength differences. ANCOVA revealed that the N and R groups experienced significant (p < .01) increases in [Vdot]O 2 max expressed in L · min ?1 (10.9 and 11.4%), ml · kg ?1 · min ?1 (10.8 and 11.7%), and ml · kgLBW ?1 · min ?1 (7.1 and 7.5%) when compared to the FW group. There were no significant differences between the N and R groups. There were no significant differences among groups in final peak torque values (after covariance), and torque at the beginning and end of the range of motion for the knee extensors, knee flexors, elbow extensors, and elbow flexors. In general, isokinetic strength values elicited by the N group compared favorably to those generated by the FW group. It was concluded that for a training period of short duration, Nautilus circuit weight training appears to be an equally effective alternative to standard free weight (strength) and aerobic (endurance) training programs for untrained individuals. 相似文献
66.
With the advent of the Next Generation Science Standards in engineering (NGSS, 2013), teachers of multiple subject areas are being asked to do more than ever before—not only to teach engineering content in the K-12 classroom but also to engage students in authentic disciplinary reading and writing as part of content learning. These standards sound good, but they beg several questions; namely, what do we know about how, why, and when do engineers read and write as they do their work every day? What do teachers charged with engineering education know about the daily practices of engineers, let alone the literacy practices? In short, little is known about the literacy practices of engineers in the course of their daily work. This article draws on participant observation, interviews, and document analysis of one research engineering laboratory to illustrate the literacy practices of one group of engineers and begins to draw implications from this work for teacher practice in achieving the NGSS engineering education standards. 相似文献
67.
Dr Elizabeth B. Silva 《Cultural Trends》2006,15(2-3):141-158
Visual art is one of the fields where, according to Bourdieu, culture is used to reproduce the class structure. Like other items in the cultural repertoire, paintings, as major examples of visual art, imply social divisions in how they are engaged with by artists, critics and audiences. Within the Bourdieusian framework, cultural engagements with paintings are interpreted as indicators of social position, since appreciation depends on a trained capacity in the family and the educational system, which is often inaccessible to less powerful sections of the population. This would imply that the sorts of paintings favoured by working-class people differ from those preferred by the middle or upper classes. More recent studies have contested the view that a gulf exists between the art tastes of different classes in ways that reproduce the class structure. The argument of the omnivore thesis that distinctions between more popular and legitimate tastes have become blurred has predominantly been based on empirical references in the field of music. This article explores this thesis on the basis of data about visual arts in the Cultural Capital and Social Exclusion project. While some differences continue to be connected to social divisions of income, education and occupational groups, important similarities are found across the board, and certain significant differences appear to relate to factors other than social class, such as ethnicity, age and gender. It is also significant that some people appear disconnected from and disinterested in paintings. 相似文献
68.
Shelly J. Schmidt Dawn M. Bohn Aaron J. Rasmussen Elizabeth A. Sutherland 《Journal of Food Science Education》2012,11(2):16-22
Abstract: The overarching goal of the Science, Technology, Engineering, and Mathematics (STEM) Education Initiative is to foster effective STEM teaching and learning throughout the educational system at the local, state, and national levels, thereby producing science literate citizens and a capable STEM workforce. To contribute to achieving this goal, we have assembled six food science demonstrations for use at all educational levels and have presented these lessons to students at the elementary through higher education levels. The focus of this article is to share these food science demonstrations and our experiences using them so that others can use them for engaging students in STEM disciplines, through food science, at any educational level. Featured demonstrations include: (1) liquid nitrogen ice cream: a matter of changing phases, (2) seeing our senses work together, (3) whipping up the cream, (4) milk versus dark: what is the difference?, (5) counting calories by burning them, and (6) culinary spherification: the wonders of cross‐linking. Overall, our experience with using these demonstrations has been very positive. Students appear engaged in the learning process and love to consume the demonstration end products. Downloadable handouts containing demonstration details for each demonstration are available as supporting information. 相似文献
69.
This paper analyses the popular RateMyProfessors (RMP) website where students evaluate instructors in higher education. A study was designed to measure (1) the awareness and utilisation of the RMP website, (2) the internal and external validity of the RMP ratings in measuring teaching effectiveness, and (3) variation in the above across disciplines. It is concluded that the category of ratings, created by the website, establishes an anti‐intellectual tone that manifests itself in comments about instructors’ personality, easiness of workload and entertainment value rather than knowledge attained. 相似文献
70.
Two language acquisition processes (comprehension preceding production of word order, the noun bias) were examined in 2- and 3-year-old children (n=10) with autistic spectrum disorder and in typically developing 21-month-olds (n=13). Intermodal preferential looking was used to assess comprehension of subject-verb-object word order and the tendency to map novel words onto objects rather than actions. Spontaneous speech samples were also collected. Results demonstrated significant comprehension of word order in both groups well before production. Moreover, children in both groups consistently showed the noun bias. Comprehension preceding production and the noun bias appear to be robust processes of language acquisition, observable in both typical and language-impaired populations. 相似文献