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72.
The results of recent studies into the use of the concept mapping heuristic seem to demonstrate that meaningful learning results through its use in science classrooms. While this underscores the need to use more effective instructional strategies in science teaching, the issue of the intervening variable of anxiety in learning and science achievement, and the possible use of a metacognitive strategy in anxiety reduction have not been addressed. This study, therefore, sought to find out if the metacognitive strategy of concept mapping reduces anxiety and thereby enhances achievement in biology. A total of 51 (30 boys, 21 girls) senior secondary one (grade 10) students participated in this experiment. Two instruments—the Zuckerman Affect Adjective Checklist and the Biology Achievement Test—were used in pre- and posttest administrations to measure the treatment effect on anxiety and achievement, respectively. Findings support the stand that concept mapping is significantly more effective than the traditional/expository teaching strategy in enhancing learning in biology. In addition, it apparently reduces students' anxiety towards the learning of biology. A significant reduction of anxiety was noticed for male subjects. 相似文献
73.
Pauline?A.?Porcaro Denise?E.?Jackson Patricia?M.?McLaughlin Cindy?J.?O’MalleyEmail authorView authors OrcID profile 《Journal of Science Education and Technology》2016,25(3):345-357
A common trend in higher education is the “flipped” classroom, which facilitates active learning during class. The flipped approach to teaching was instituted in a haematology ‘major’ class and the students’ attitudes and preferences for the teaching materials were surveyed. The curriculum design was explicit and involved four major components (1) the preparation of the students; (2) the weekly pre-class work; (3) the in-class active learning strategies and (4) closing the learning loop using formative quizzes. Each of these components is discussed in detail and was informed by sound pedagogical strategies. Several different sources of information and several freely available software tools to engage the students are discussed. Two iterations are reported here, with improved pass rate for the final examination from 47 to 48 % in the traditional class to 56–65 % in the flipped classroom approach. The majority of students (93 and 89 %) came to the class prepared, after viewing the screencasts and engaged fully with the activities within the face-to-face time. The students perceived that solving case studies (93 %) was the most beneficial activity for their learning and this was closely followed by the production of essay plans (71 %). The majority of students recommended that this approach be repeated the following year (69 and 75 %). 相似文献
74.
A Methylome‐Wide Association Study of Trajectories of Oppositional Defiant Behaviors and Biological Overlap With Attention Deficit Hyperactivity Disorder 下载免费PDF全文
Edward D. Barker Esther Walton Charlotte A.M. Cecil Richard Rowe Sara R. Jaffee Barbara Maughan Thomas G. O'Connor Argyris Stringaris Alan J. Meehan Wendy McArdle Caroline L. Relton Tom R. Gaunt 《Child development》2018,89(5):1839-1855
In 671 mother–child (49% male) pairs from an epidemiological birth cohort, we investigated (a) prospective associations between DNA methylation (at birth) and trajectories (ages 7–13) of oppositional defiant disorder (ODD), and the ODD subdimensions of irritable and headstrong; (b) common biological pathways, indexed by DNA methylation, between ODD trajectories and attention deficit hyperactivity disorder (ADHD); (c) genetic influence on DNA methylation; and (d) prenatal risk exposure associations. Methylome‐wide significant associations were identified for the ODD and headstrong, but not for irritable. Overlap analysis indicated biological correlates between ODD, headstrong, and ADHD. DNA methylation in ODD and headstrong was (to a degree) genetically influenced. DNA methylation associated with prenatal risk exposures of maternal anxiety (headstrong) and cigarette smoking (ODD and headstrong). 相似文献
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Louisa R. Peralta Donna O’Connor Wayne G. Cotton Andrew Bennie 《Teaching Education》2016,27(3):248-266
In this paper, we investigate the effects of a community- and school-based service learning experience (SLE) on pre-service physical education teachers’ Indigenous knowledge, cultural competency and pedagogy. Informed by the theoretical tenets of Indigenous research methodologies, experiential learning and critical reflection, we examine 55 final-year pre-service physical education teachers’ (age: 21.9 [8.3]; 10.7% low SES; 68% females) cultural learning and competency in a core unit of study with a six-week SLE. Measures of their experiences included reflective journals, multicultural teaching competency scales and focus group interviews. Findings support the design of the SLE, with statistically significant changes in pre-service teachers’ perceptions of their cultural competency (p < 0.001). Pre-service teachers were able to challenge their assumptions about Indigenous students, plan and implement student-centred and culturally relevant pedagogies. Attention is drawn to the design of this SLE and demonstrates the importance of using Indigenous community members and teachers as mentors, which has not been explored in previous SLE studies. 相似文献
77.
The Inductive Query By Example (IQBE) paradigm allows a system to automatically derive queries for a specific Information Retrieval System (IRS). Classic IRSs based on this paradigm [Smith, M., & Smith, M. (1997). The use of genetic programming to build Boolean queries for text retrieval through relevance feedback. Journal of Information Science, 23(6), 423–431] generate a single solution (Boolean query) in each run, that with the best fitness value, which is usually based on a weighted combination of the basic performance criteria, precision and recall. 相似文献
78.
The objective of this study was to evaluate acrosin activity in spermatozoa of infertile Nigerian men and to compare with
those of the fertile men. The acrosin activity was evaluated using the Acroscreen reagent kit. The acrosin activity of the
fertile men was 40.7±5.2 mIU/106 sperm (range 30.1–51.3) and those of the infertile men was 22.4±8.33 mIU/106 sperm (range 5.7–39.1). The difference in the mean was statistically significant (P<0.001). There was a subpopulation of
the infertile men who had their acrosin activity within normal range of the fertile men, 32.9±1.57 mIU/106 sperm. But the difference in the mean was statistically significant (P<0.001). Acrosin activity decreased with increased
morphological changes in the spermatozoa. It is concluded that acrosin activity in the infertile Nigerian men is significantly
lower than that in the fertile men. Acrosin activity may also be affected by morphological changes in the spermatozoa. 相似文献
79.
O. P. Sanjay 《Indian journal of clinical biochemistry : IJCB》2004,19(1):40-44
Although potassium is critical for normal electro physiology, the associations between pre-operative serum potassium level
and peri-operative adverse events such as arrhythmias in cardiac surgery have not been examined in detail.
The objective of this study was to determine the prevalence of abnormal pre-operative serum potassium levels and whether such
levels were associated with adverse peri-operative events in 50 patients undergoing coronary artery bypass grafting. Intra-operative
and post-operative arrhythmias, the need for cardio-pulmonary resuscitation, cardiac death and death due to any cause prior
to discharge from the post-operative intensive care unit were studied. The incidence for adverse outcome was 0.5% for death,
0.5% for cardiac death and 2% for cardio pulmonary resuscitation in patients with hypokalemia (serum potassium level <3.5
meq. L−1). Hypokalemia was found to be a predictor of serious peri-operative (OR:2.2; 95% Cl: 1.2–4.1) and post-operative arrhythmias
(OR: 1.7;95%Cl: 1.0–2.7).
Pre-operative potassium repletion is low cost and low risk treatment measure and the data from this study suggests that screening
and repletion be considered in patients scheduled for cardiac surgery. 相似文献
80.