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191.
Inquiry engagement is a newly defined construct that represents the participation in carrying out practices of science and engineering to achieve learning outcomes and is influenced by learners’ personalities and teachers’ roles. Expectancy value theory posits that attainment values are important components of task values that, in turn, directly influence students’ achievement-related choices and performance. The current paper developed and validated the McGill Attainment Value for Inquiry Engagement Survey (MAVIES) with undergraduate students in STEM disciplines. The MAVIES is a 67-item, learner-focused survey that addresses four components that are theoretically important for engaging in scientific inquiry: (a) teachers’ roles, (b) students’ personalities, (c) inquiry learning outcomes, and (d) practices of science and engineering. Evidence for internal consistency and construct, content, and criterion validity was obtained from 85 undergraduates who had experience with scientific inquiry in diverse STEM fields. Confirmatory factor analyses confirmed factors that were consistent with role theory, Big Five personality traits, revised Bloom’s learning outcomes, and the Next Generation Science Standards. The MAVIES instrument is a reliable and valid instrument for measuring undergraduate students’ attainment values for scientific inquiry engagement in STEM disciplines.  相似文献   
192.
The purpose of this study was to compare the effectiveness of two instructional modes, discovery and expository, for teaching science knowledge, both application and recall, and science attitude to fifth-grade male and female Egyptian students. The population used for this study consisted of 276 fifth-grade students in two Egyptian schools. Twelve 45-min science classes meeting over a 21-day period made up the treatment period, with each of the two teachers instructing six of the 12 class periods for all eight subgroups of students. The results warrant the following conclusions: Fifth-grade Egyptian students taught by the discovery method scored higher in science achievement, both recall and application, than students taught by the expository method. Students taught by the discovery method scored higher in science attitude than students taught by the expository method. Female Egyptian students scored in science achievement and science attitude similar to males.  相似文献   
193.
Educational technology research and development - The rapid advancements in online education have pointed to a new open learning approach using Open Educational Resources (OER). In this approach,...  相似文献   
194.
Orphans and vulnerable children affected by HIV/AIDS (HIV OVC) are at risk for cognitive difficulties and lack of access to education. Interventions addressing cognitive or educational outcomes for HIV OVC worldwide were examined through systematic searches conducted from October 2016 to 2019. We examined the summative effectiveness of interventions and the specific effects of participant age and intervention length. Interventions targeting cognitive outcomes had a small, significant effect, with no effect of moderating variables. Interventions targeting educational outcomes had significant effects. Educational interventions over 1 year were effective, but effects of intervention length were not significant. Overall, this review provides support for the effectiveness of interventions targeting cognitive and educational outcomes for OVC and highlights the need for more research on such interventions.  相似文献   
195.

Objective

Scandix pecten-veneris L. is a less studied wild edible herb and is considered an extinct plant species in many parts of the world. This study was designed to evaluate its phytochemical composition and biological potential of S. pecten-veneris L.

Methods

Phytochemicals including alkaloids, flavonoids, polyphenols, and tannins were determined in extracts of S. pecten-veneris. Antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), while reducing power was tested by ferric reducing/antioxidant power (FRAP) assay. Antimicrobial activity against seven bacterial and four fungal strains was evaluated using agar well diffusion assay. Enzymes inhibition study was performed for urease, phosphodiesterase-I, and catalase-II.

Results

S. pecten-veneris showed moderate antiradical activity and reducing potential of hydroxyl radicals to about 20% of the initial value. The antioxidant activity of various extracts of S. pecten-veneris showed a linear correlation with total phenolic contents in the order of water>n-butanol>chloroform>ethyl acetate>methanol extracts. S. pecten-veneris leaves showed the highest inhibitory activity against Staphylococcus aureus while the highest antifungal activity was observed against Candida albicans. The plant extract was most potent against urease enzymes but showed moderate activity against phosphodiestrase-I and carbonic anhydrase-II.

Conclusions

Our data demonstrate that in addition to its culinary uses, S. pecten-veneris has good medicinal potential and hence could be used for treating some specific health ailments.
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196.
197.
The effect of sodium oxalate and methionine supplementation on stone-related constituents of urine was studied in 18 adult male guinea pigs. Their serum and tissue chemistry and histological changes in urinary tract and liver were also studied. The calciuretic effect of methionine was blocked by oxalate. The decrease in uric acid and citric acid, caused by oxalate, was offset by methionine. Oxalate-induced crystalluria and calcium and oxalate deposition in kidney tissue were lessened by methionine. Administration of Varuna, an indigenuous drug, to oxalate and methionine-supplemented animals prevented either totally or partially most of the urolithogenic effects of oxalate and methionine.  相似文献   
198.
The phenomenon of “digital divide” is complex and multidimensional, extending beyond issues of physical access. The purpose of this study was to develop a scale to measure a range of factors related to digital divide among higher education faculty and to evaluate its reliability and validity. Faculty’s Information and Communication Technology Access (FICTA) scale was tested and validated with 322 faculty teaching in public and private sector universities. Principal components analysis with varimax rotation confirmed an 8-factor solution corresponding to various dimensions of ICT access. The 57-item FICTA scale demonstrated good psychometric properties and offers researchers a tool to examine faculty’s access to ICT at four levels – motivational, physical, skills, and usage access.  相似文献   
199.
In this paper, we propose and study a stochastic predator–prey model with herd behavior. Firstly, by constructing a suitable stochastic Lyapunov function, we establish sufficient conditions for the existence and uniqueness of an ergodic stationary distribution of the positive solutions to the model. Then we establish sufficient conditions for extinction of the predator population in two cases, that is, the first case is the prey population survival and the predator population extinction; the second case is all the prey and predator populations extinction. Finally, some examples together with numerical simulations are introduced to illustrate the theoretical results.  相似文献   
200.
In this paper, we investigate the dynamical behavior of a stochastic dengue epidemic model. First of all, by constructing a suitable stochastic Lyapunov function, we obtain sufficient conditions for the existence of an ergodic stationary distribution of the positive solutions to the model. Then we establish sufficient conditions for extinction of the diseases. The existence of stationary distribution implies stochastic weak stability.  相似文献   
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