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111.
V. D. Chamizo Clara A. Rodríguez Irene Torres Marta N. Torres N. J. Mackintosh 《Learning & behavior》2014,42(4):348-356
In Experiment 1, two groups of female rats were trained in a triangular pool to find a hidden platform whose location was defined in terms of a single a landmark, a cylinder outside the pool. For one group, the landmark had only a single pattern (i.e., it looked the same when approached from any direction), while for the other, the landmark contained four different patterns (i.e., it looked different when approached from different directions). The first group learned to swim to the platform more rapidly than the second. Experiment 2 confirmed this difference when female rats were trained in a circular pool but found that male rats learned equally rapidly (and as rapidly as females trained with the single-pattern landmark) with both landmarks. This second finding was confirmed in Experiment 3. Finally, in Experiment 4a and 4b, male and female rats were trained either with the same, single-pattern landmark on all trials or with a different landmark each day. Males learned equally rapidly (and as rapidly as females trained with the unchanged landmark) whether the landmark changed or not. We conclude that male and female rats learn rather different things about the landmark that signals the location of the platform. 相似文献
112.
Randy V. Bradley Chetan S. Sankar Howard R. Clayton Victor W. Mbarika P. K. Raju 《Decision Sciences Journal of Innovative Education》2007,5(1):151-168
Colleges of Business (COBs) have experienced high growth rates in the past decade and many colleges are imposing minimum grade point average (GPA) requirements for students to enter or remain in the college. A primary reason for this requirement may be the belief that students with high GPAs are more inclined to demonstrate higher‐order cognitive skills (HOCS) than students with low GPAs. It is not clear whether the link is valid. This study hypothesizes that students with high GPAs who are taught in the same way as students with lower GPAs will have higher perceptions of improved HOCS. We conducted an experiment in which students, with varying GPAs, at three large universities primarily used multimedia instructional materials. We obtained the students' perceptions of their improved HOCS from their responses to a survey. A regression analysis of the data reveals that the relationship between GPAs and students' perceived improvement in HOCS is significant (p < .001). We conclude the study by recommending that (a) it is critical to use research methodologies to evaluate perceived and actual learning improvements, (b) COB policies to implement GPA restrictions on admission are worthwhile, and (c) case studies need to be used much more frequently in undergraduate COB classes. 相似文献
113.
T. V. Zakharchuk 《Scientific and Technical Information Processing》2012,39(4):208-214
This paper presents the results from a survey of the leading bibliographical scientists of the country on the problems of the formation and development of scientific schools in bibliographical science, the functions performed by them, and signs that are immanent to them. 相似文献
114.
G. V. Prosser 《Instructional Science》1978,7(4):359-383
Both active questions i.e. questions asked by subjects, and provided (or passive) questions i.e. offered to subjects as problems for solution, had been found to facilitate learning and retention of prose material when subjects were faced with a task of sufficient difficulty to challenge their competence. With difficult prose, boys and low ability subjects had gained most from active questions. These effects were more pronounced in the long term. In this study, the effects of relevant active questions i.e. questions which subjects can put alongside answers, are investigated and compared with those of active and provided questions, over a series of six presentations for both the short and the long term (i.e. after ten months). In the short term, although active questions give greater help than provided questions on the first presentation, and relevant active questions give the greatest improvement between the first and second presentations, provided questions are the most helpful overall. In the long term, however, both the active questions treatments prove to be as effective as provided questions. For low ability boys, the difference between treatments is negligble even in the short term; under the relevant active questions treatment the number of questions asked is greater; and the decline in inspection time over presentations is negligible.This study formed part of a Schools' Council Research project (Director: Dr. W. P. Robinson) in the Department of Psychology, University of Southampton. 相似文献
115.
The aim of this study was to examine the effects of muscle-tendon length on joint moment and power during maximal sprint starts. Nine male sprinters performed maximal sprint starts from the blocks that were adjusted either to 40 degrees or 65 degrees to the horizontal. Ground reaction forces were recorded at 833 Hz using a force platform and kinematic data were recorded at 200 Hz with a film camera. Joint moments and powers were analysed using kinematic and kinetic data. Muscle - tendon lengths of the medial gastrocnemius, soleus, vastus medialis, rectus femoris and biceps femoris were calculated from the set position to the end of the first single leg contact. The results indicated that block velocity (the horizontal velocity of centre of mass at the end of the block phase) was greater (P < 0.01) in the 40 degrees than in the 65 degrees block angle condition (3.39 +/- 0.23 vs. 3.30 +/- 0.21 m . s(-1)). Similarly, the initial lengths of the gastrocnemius and soleus of the front leg in the block at the beginning of force production until half way through the block phase were longer (P < 0.001) in the 40 degrees than in the 65 degrees block angle condition. The initial length and the length in the middle of the block phase were also longer in the 40 degrees than in the 65 degrees block angle condition both for both the gastrocnemius (P < 0.01) and soleus (P < 0.01-0.05) of the rear leg. In contrast, the initial lengths of the rectus femoris and vastus medialis of the front leg were longer (P < 0.05) in the 65 degrees than in the 40 degrees block angle condition. All differences gradually disappeared during the later block phase. The peak ankle joint moment (P < 0.01) and power (P < 0.05) during the block phase were greater in the 40 degrees than in the 65 degrees block angle condition for the rear leg. The peak ankle joint moment during the block phase was greater (P < 0.05) in the 40 degrees block angle for the front leg, whereas the peak knee joint moment of the rear leg was greater (P < 0.01) in the 65 degrees block angle condition. The results suggest that the longer initial muscle-tendon lengths of the gastrocnemius and soleus in the block phase at the beginning of force production contribute to the greater peak ankle joint moment and power and consequently the greater block velocity during the sprint start. 相似文献
116.
India seems to have the highest prevalence of osteoporosis. With growing awareness of osteoporosis and its impact on life
span especially in India, special attention is being paid to early detection, management and treatment of postmenopausal osteoporosis
in women. Measurement of BMD and osteocalcin are of value in estimating bone turnover rates. The aim of this study is (1)
to measure the specific, sensitive bone formation marker such as osteocalcin and BMD in postmenopausal osteoporosis women
and postmenopausal non-osteoporosis women; (2) the follow up study to evaluate the impact of specific antiresorptive therapy
(alendronate + calcium + vitamin D) regimen in postmenopausal osteoporosis by assaying osteocalcin and BMD. Sixty clinically
diagnosed postmenopausal osteoporosis patients and 60 normal subjects (postmenopausal non-osteoporosis women) were recruited
as control. Mean bone mineral density T score and Z score was significantly decreased (P < 0.001) in postmenopausal osteoporosis patients as compared to controls. Highly significant increase in the mean score of
BMD—T score and Z score from baseline to post therapy of 3 months was observed in postmenopausal osteoporosis women. Serum osteocalcin levels
were significantly increased (P < 0.001) as compared to control group. Serum osteocalcin levels were decreased significantly (P < 0.001) from baseline to post therapy of 3 months in postmenopausal osteoporosis women. BMD is the best quantifiable predictor
of osteoporotic fracture and osteocalcin is specific, sensitive, promising, currently used marker for better prognosis of
osteoporosis and for monitoring responses to antiresorptive therapy. 相似文献
117.
Gerti Pishtari María J. Rodríguez-Triana Edna M. Sarmiento-Márquez Mar Pérez-Sanagustín Adolfo Ruiz-Calleja Patricia Santos Luis P. Prieto Sergio Serrano-Iglesias Terje Väljataga 《British journal of educational technology : journal of the Council for Educational Technology》2020,51(4):1078-1100
Mobile and Ubiquitous Learning (m/u-learning) are finding an increasing adoption in education. They are often distinguished by hybrid learning environments that encompass elements of formal and informal learning, in activities that happen in distributed settings (indoors and outdoors), across physical and virtual spaces. Despite their purported benefits, these environments imply additional complexity in the design, monitoring and evaluation of learning activities. The research literature on learning design (LD) and learning analytics (LA) has started to deal with these issues. This paper presents a systematic literature review of LD and LA, in m/u-learning. Apart from providing an overview of the current research in the field, this review elicits elements of common ground between both communities, as shown by the similar learning contexts and complementary research contributions, and based on the research gaps, proposes to: address m/u-learning beyond higher education settings, reinforce the connection between physical and virtual learning spaces, and more systematically align LD and LA processes. 相似文献
118.
Jessica V. Whittaker Mable B. Kinzie Virginia Vitiello Jamie DeCoster Christina Mulcahy Emily A. Barton 《Journal of research on educational effectiveness》2020,13(2):177-212
abstractThis randomized controlled trial examined effects of the MyTeachingPartner-Math/Science intervention on the quality and quantity of teachers’ mathematics and science instruction, and children’s mathematics and science outcomes in 140 pre-kindergarten classrooms. Teachers participated in the intervention for two years with consecutive cohorts of children. Results from Year 1 are considered experimental, however due to high levels of attrition, results from Year 2 are considered quasi-experimental. Across both years, intervention teachers exhibited higher quality and quantity of instruction. In Year 1, there were no significant effects of the intervention on children’s outcomes. In Year 2, children in intervention classrooms made greater gains in teachers’ ratings of mathematics and science skills and performed better on a spring assessment of science skills. These results have implications for designing and evaluating professional development aimed at supporting children’s mathematics and science knowledge and skills. 相似文献
119.
Leonie V. D. E. Vogelsmeier Jeroen K. Vermunt Eeske van Roekel Kim De Roover 《Structural equation modeling》2019,26(4):557-575
When time-intensive longitudinal data are used to study daily-life dynamics of psychological constructs (e.g., well-being) within persons over time (e.g., by means of experience sampling methodology), the measurement model (MM)—indicating which constructs are measured by which items—can be affected by time- or situation-specific artifacts (e.g., response styles and altered item interpretation). If not captured, these changes might lead to invalid inferences about the constructs. Existing methodology can only test for a priori hypotheses on MM changes, which are often absent or incomplete. Therefore, we present the exploratory method “latent Markov factor analysis” (LMFA), wherein a latent Markov chain captures MM changes by clustering observations per subject into a few states. Specifically, each state gathers validly comparable observations, and state-specific factor analyses reveal what the MMs look like. LMFA performs well in recovering parameters under a wide range of simulated conditions, and its empirical value is illustrated with an example. 相似文献
120.
OBJECTIVE: The purpose of this study was to clinically assess children's reactions to videocolposcopy with real-time observation of magnified anogenital images (VCO), and to evaluate whether these reactions are affected by patient or other characteristics such as response to preparation, disclosure of child sexual abuse (CSA), or examination findings. METHOD: Consecutive cases of children ages less than 18 years referred to a children's hospital clinic for nonemergent evaluation of suspected CSA during 1997 through 1999 were studied. We noted the child's response with clinical observation before and after videocolposcopy, and used the Genital Examination Distress Scale (GEDS) after evaluation. We compared these responses to patient gender, age, ethnicity, pubertal status, disclosure of child sexual abuse (CSA), and physical examination findings using univariate and regression analyses. RESULTS: Two hundred twenty-seven children (mean age 7.2 years, range 0-17) underwent videocolposcopy, of whom 55.1% disclosed sexual abuse and 17.2% had a positive examination. More than 80% were female, prepubertal, and non-Hispanic White. Most (85%) watched their examination on the monitor and were either cooperative or enthusiastic before and after videocolposcopy. Fewer very young children (ages 0-3 years) or female adolescents (13-17 years) watched the monitor. Summed GEDS scores were strongly correlated with observed responses after the procedure (p = .01), and children with CSA disclosure were three times more likely to watch the monitor and five times more likely than those without disclosure to have improved comfort. Other patient characteristics were not significantly associated with patient reaction to VCO. CONCLUSIONS: Most children are interested in watching their anogenital examination using magnified real-time images obtained during videocolposcopy and tolerate the procedure well. The GEDS is highly correlated with subjective clinical observation. While some children may particularly benefit from participating in their examination by using VCO, long-term effects of the evaluation and any relationship of a child's reaction to videocolposcopy with their history of sexual victimization remain to be established. 相似文献