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This study examined the similarities and differences in experienced secondary science teachers' planning, teaching, and reflecting on their teaching, when teaching in their science area of certification and when teaching in another science area. The study also focused on the influence of these teachers' content knowledge, pedagogical knowledge, and pedagogical content knowledge on their planning, teaching, and reflecting. Experienced teachers were observed and interviewed while teaching classes in their science area of certification, and in another science area they were teaching for the first or second time. Both similarities and differences in teaching were found in the two areas for all three teachers. For example, their planning and postlesson reflections were similar in both areas. In the interactive phase of teaching more differences were observed. Many aspects of their teaching resembled that of expert teachers in other studies. In the unfamiliar science area, the teachers sometimes acted like novice teachers. However, they were able to draw upon their pedagogical knowledge to provide a framework for their teaching in both science areas. Their wealth of pedagogical knowledge, and pedagogical content knowledge for general science topics, seemed to sustain them in whatever content they were teaching. Recommendations for further study and implications for teacher education are discussed. 相似文献
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Reading and Writing - The present study investigates the effectiveness of question paraphrases in supporting students’ understanding of a specific task. Secondary school students (i.e.,... 相似文献
177.
Perianal findings in prepubertal children selected for nonabuse: a descriptive study 总被引:6,自引:0,他引:6
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
178.
Qualitative studies of the teacher labor market suggest that problems and remedies generated by quantitative research fail to capture the most dynamic variables which are affecting the supply and demand of public school teachers. For example, quantitative research has not accounted for (1) the continual exiting and reentering of urban teachers, (2) the considerable bifurcation between urban and rural teacher labor markets as reflected in teacher mobility and cultural economic opportunities, (3) local definitions of labor market needs and teacher quality, and (4) the demanding and stressful working conditions of teaching, which are having a systemic and adverse effect on the occupation. 相似文献
179.
Wojciech Szczęsny Magdalena Kuligowska-Prusińska Stanisław Dąbrowiecki Jakub Szmytkowski Adrian Reśliński Maciej Słupski 《Journal of Zhejiang University. Science. B》2018,19(1):65-70
Purpose
Metalloproteinases are a key component of the pathogenesis of abdominal hernias. Obesity is considered a risk factor in herniogenesis and hernia recurrence. The aim of this study was to evaluate the serum concentrations of metalloproteinase-2 (MMP-2), MMP-9, MMP-13, and adiponectin in morbidly obese and nonoverweight controls.Materials and methods
The participants were recruited from among patients undergoing bariatric and non-bariatric surgery and divided into two groups: I (body mass index (BMI)≥35 kg/m2, n=40) and II (BMI<25 kg/m2, n=30). Serum concentrations of MMP-2, MMP-9, MMP-13, and adiponectin were measured using enzyme-linked immunosorbent assay (ELISA).Results
A statistically significant difference between groups was observed for MMP-2 concentration. The median MMP-9 concentration was higher in the obese group, but the difference was not statistically significant. Median MMP-13 concentrations did not differ between groups. Serum adiponectin concentration was insignificantly higher in the non-obese group.Conclusions
The elevated serum MMP-2 and MMP-9 concentrations in obese individuals may be related to the higher incidence of incisional hernias in this population.180.
Loneliness and Peer Relations in Young Children 总被引:13,自引:0,他引:13
Recent studies indicate that feelings of loneliness and social dissatisfaction can be reliably assessed with third- through sixth-grade children, and that children who are sociometrically rejected by their peers are significantly more lonely than other children. The present research was designed (a) to examine whether loneliness could be reliably assessed in a population younger than previously studied, (b) to learn whether young children who are poorly accepted by peers report elevated levels of loneliness and social dissatisfaction, (c) to assess whether young children understand the concept of loneliness, and (d) to examine the behavioral characteristics of lonely young children. Kindergarten and first-grade children (N = 440) responded to a questionnaire about feelings of loneliness and social dissatisfaction in school. A subset of children (N = 46) were individually interviewed to assess their understanding of loneliness. To assess sociometric status and behavior, peers were asked to respond to various sociometric measures and behavioral assessment items. Teachers also provided behavioral information about children using a newly developed instrument. Results indicated that nearly all children understood loneliness, that loneliness was reliably assessed in young children, and that poorly accepted children were more lonely than other children. In addition, children who reported the most loneliness were found to differ from others on several behavioral dimensions. 相似文献