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21.
The cadence that maximises power output developed at the crank by an individual cyclist is conventionally determined using a laboratory test. The purpose of this study was two-fold: (i) to show that such a cadence, which we call the optimal cadence, can be determined using power output, heart-rate, and cadence measured in the field and (ii) to describe methodology to do so. For an individual cyclist's sessions, power output is related to cadence and the elicited heart-rate using a non-linear regression model. Optimal cadences are found for two riders (83 and 70 revolutions per minute, respectively); these cadences are similar to the riders’ preferred cadences (82–92?rpm and 65–75?rpm). Power output reduces by approximately 6% for cadences 20?rpm above or below optimum. Our methodology can be used by a rider to determine an optimal cadence without laboratory testing intervention: the rider will need to collect power output, heart-rate, and cadence measurements from training and racing sessions over an extended period (>6 months); ride at a range of cadences within those sessions; and calculate his/her optimal cadence using the methodology described or a software tool that implements it.  相似文献   
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One hundred and sixty college students read three fictitious biographical passages according to either imagery-mnemonic or no-strategy control instructions. In one mnemonic condition, subjects formed separate images involving each biographical name and its associated facts: in another mnemonic condition, the biographical name and its associated facts were integrated within a single composite image. Relative to an interference-control condition, integrated mnemonic subjects recalled more factual information, whereas separate mnemonic subjects did not. In addition, the recall of integrated mnemonic subjects was statistically no different from that of a noninterference control condition, whereas the recall of separate mnemonic subjects was lower. Both theoretical and educational implications of the results are discussed. The first author’s contribution to this work was supported by an Organized Research Grant from the Graduate School of Illinois State University. The second author’s contribution was supported by the National Institute of Education under Grant No. NIE-G-81-0009 to the Wisconsin Center for Education Research and was facilitated by a Romnes Faculty Fellowship from the Graduate School of the University of Wisconsin, Madison.  相似文献   
24.
The results of the perianal portion of a project designed to collect normative data of the anogenital anatomy from a representative sample of prepubertal children is presented. A total of 318 children were examined by three physicians from a child sexual abuse evaluation program. After screening for the onset of puberty and the possibility of undetected abuse, 267 subjects remained. The sample included 161 girls and 106 boys ranging in age from 2 months to 11 years. The perianal findings that were encountered with the greatest frequency included erythema (41%), increased pigmentation (30%), and venous engorgement (52%) after two minutes in the knee-chest position. Wedge-shaped smooth areas in the midline, with or without depressions, were found both anterior and posterior to the anus in 26% of the children. Anal skin tags/folds were discovered anterior to the anus in 11%. In 49% of the children there was some dilatation of the anus which opened and closed intermittently in 62%. Flattening of the anal verge and rugae occurred during dilatation by the midpoint of the examination in 44% and 34%, respectively. Perianal findings that were found infrequently in all subgroups included skin tags/folds (0%) and scars (1%) outside the midline, anal dilatation greater than 20 mm without the presence of stool in the rectal ampulla (1.2%), irregularity of the anal orifice after complete dilatation (3%), and prominence of the anal verge (3%). No abrasions, hematomas, fissures, or hemorrhoids were encountered. Less commonly detected findings within specific subgroups included perianal erythema in girls (32%) as compared to boys (57%), pigmentation in the lighter skinned white children (22%) when compared to black (53%) and Hispanic (58%) children, and venous congestion at the beginning of the examination (7%) when compared to the same findings after four minutes in the knee-chest position (73%). There were no perianal skin tags/folds found in the boys. The relatively high incidence of perianal soft tissue changes that were found in this study, when compared to the frequency of similar observations in children suspected of having been sexually abused, reemphasizes the caution medical examiners must exercise in rendering an opinion as to the significance of medical findings.  相似文献   
25.
Most distance learning institutions collect vast amounts of learning data. Making sense of this ‘Big Data’ can be a challenge, in particular when data are stored at different data warehouses and require advanced statistical skills to interpret complex patterns of data. As a leading institute on learning analytics, the Open University UK instigated in 2012 a Data Wrangling initiative. This provided every Faculty with a dedicated academic with expertise data analysis and whose task is to provide strategic, pedagogical and sense-making advice to staff and senior management. Given substantial changes within the OU (e.g. new Faculty structure, real-time dashboards, two large-scale adoptions of predictive analytics approaches, increased reliance on analytics), this embedded case study provides an in-depth review of lessons learned of five years of data wrangling. We will elaborate on the design of the new structure, its strengths and potential weaknesses, and affordances to be adopted by other institutions.  相似文献   
26.
After a decade of virtual learning environments (VLEs) in higher education, many teachers still use only a minimum of its affordances. This study looked at how academic staff interacted with a new and unknown VLE in order to understand how technology acceptance and support materials influence (perceived and actual) task performance. In an experimental design, 36 participants were split into a control (online help) and experimental (instructor video) condition and completed five common teaching tasks in a new VLE. In contrast to most technology acceptance model research, this study found that perceived usefulness of the VLE was not related to (perceived) task performance. Perceived ease of use was related to intentions and actual behaviour in the VLE. Furthermore, no significant difference was found between the two conditions, although the experimental condition led to a (marginal) increase in time to complete the tasks.  相似文献   
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In an effort to understand the role of interhemispheric transfer in numerical development, we investigated the relationship between children's developing knowledge of numbers and the integrity of their white matter connections between the cerebral hemispheres (the corpus callosum). We used diffusion tensor imaging (DTI) tractography analyses to test the link between the development of the corpus callosum and performance on symbolic and non-symbolic numerical judgment tasks. We were especially interested in the interhemispheric connections of parietal cortex in 6-year-old children, because regions of parietal cortex have been implicated in the development of numerical skills by several prior studies. Our results revealed significant structural differences between children and adults in the fibers of the corpus callosum connecting the left and right parietal lobes. Importantly, these structural differences were predictive of individual differences among children in performance on numerical judgment tasks: children with poor numerical performance relative to their peers exhibited reduced white matter coherence in the fibers passing through the isthmus of the corpus callosum, which connects the parietal hemispheres.  相似文献   
29.
Frank Shushok Jr., T. Laine Scales, Rishi Sriram, and Vera Kidd share some initial thoughts about responses to their Campus Residential Experience Survey. Do you recognize your institution?  相似文献   
30.
A technique is presented for partitioning N students into K groups of fixed sizes using a given measure of proximity for all student pairs. The measure of proximity is typically calculated from a set of variables, such as completed curriculum units or learning style, and constitutes the data needed for a criterion of partition fit. This latter index is explicitly defined by the sum of within-group proximities and when used in conjunction with the optimization procedure discussed, homogeneous groups can be obtained that satisfy externally imposed size requirements. Finally, a simple generalization is suggested for the related task of grouping students to meet upper limit size constraints only.  相似文献   
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