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991.
Jennifer R. Warren Michael L. Hecht David A. Wagstaff Elvira Elek Khadidiatou Ndiaye Patricia Dustman Flavio F. Marsiglia 《Journal of Applied Communication Research》2006,34(2):209-227
This study sought to determine if exposure to two communication-oriented activities, videotapes and public service announcements, accounts for changes in substance use among adolescents participating in the Drug Resistance Strategies Project's keepin' it REAL adolescent substance use prevention curriculum. Middle-school students (4,734, 72% Latino) responded to questionnaires related to these analyses. An analysis of covariance (ANCOVA) model was fit separately to six substance use outcomes. The results suggested that intervention students who saw four or five videos engaged in less substance use in the past month than did students who saw fewer videos. Having seen the PSAs one or more times did not predict the reported change in substance use. 相似文献
992.
993.
Yi-Feng Wang Chunqiu Zhang Keni Yang Yufei Wang Shaobo Shan Yan Yan Kenneth A Dawson Chen Wang Xing-Jie Liang 《国家科学评论(英文版)》2021,8(6):17-27
Liposomes, especially cationic liposomes, are the most common and well-investigated nanocarriers for biomedical applications, such as drug and gene delivery. Like other types of nanomaterials, once liposomes are incubated in a biological milieu, their surface can be immediately cloaked by biological components to form a protein corona, which confers a new ‘biological identity’ and modulates downstream interactions with cells. However, it remains unclear how the protein corona affects the transportation mechanism after liposomes interact with cells. Here, we employed home-made aggregation-induced-emission-visualized nanoliposomes TR4@Lipo as a model to investigate transportation with or without the protein corona by optical imaging techniques. The results show that the protein corona can change the cellular transportation mechanism of TR4@Lipo from energy-independent membrane fusion to energy-dependent endocytosis. The protein corona also modulates the intracellular distribution of loaded cargoes. This knowledge furthers our understanding of bio-nano interactions and is important for the efficient use of cationic liposomes. 相似文献
994.
Sarah M. Bonner Jennifer A. Somers Gwendelyn J. Rivera Leslie S. Keiler 《Instructional Science》2017,45(4):417-438
We investigated perceptions about learning strategy use and instructional roles among a sample of high needs adolescents (n = 230) who acted as near-peer instructional facilitators. The sample was drawn from science and mathematics classes in nonselective public secondary schools in New York City. Students participated in an inschool intervention that draws on social constructivism, theory and research on metacognition and learning strategies, role theory, and empirical findings from the peer-to-peer learning literature to promote advanced achievement among students who act as facilitators. Using a pre- and post-test single group design, we surveyed student instructional facilitators before and after program participation and related their perceptions about learning strategy use and perceptions about teaching roles to data about academic achievement. We found no survey gains in student perceptions about learning strategies or instructional roles between pre-survey (fall) and post-survey (spring). We found small but significant effects of individual perceptions about learning strategies and teaching roles on academic gains among instructional facilitators. The study also suggests that an in-school near-peer facilitated learning program can be an effective means to raise achievement in urban high schools. The study provides partial support for theories that hold that metacognition and role perceptions are involved in the academic gains of instructional facilitators, as gains in these dimensions were small compared to achievement gains. 相似文献
995.
996.
Chinese students at an English-Language university: Prediction of academic performance 总被引:1,自引:0,他引:1
There is a paucity of systematic research on prediction of success at the tertiary education level for Asian students, despite the important role that universities play in Asian communities, and despite the increasing numbers of such students who are coming to the West to study. This study reviews evidence collected over the past ten to fifteen years, which relates to the issue of prediction of academic performance of Chinese students at an English-Language and Western-oriented university - the University of Hong Kong. This review is complemented by an analysis of data collected longitudinally over a five year period, using multiple regression, multiple correlation, path analysis and canonical correlation analyses. The results provide evidence of factors which are important in determining the ability of a student to adapt to the foreign cultural and language barriers that exist at this university. In particular, ability in English language and mathematics provides good and reasonably independent predictors of success. The data show the importance of considering the cultural background of students when assessing their aptitude for study, and offer information for Western universities regarding their admissions procedures for Chinese students. 相似文献
997.
998.
The authors examine the problems of ex-post evaluation of the benefits deriving from services provided by Government Laboratories. They concentrate on the difficulties of conducting meaningful ex-post studies since they feel that too many claims are made on the basis of inadequate, incomplete economic assessments using data that would not be substantiated if probed deeply. Their views are based on a review of nine years' practical evaluation experience.The paper defines three ways in which services/information sources can link up with intended recipients, and discusses the practical problems associated with assessing the impact of services in each case. These problems range from sampling errors and sample bias in questionnaire approaches, to limited respondent knowledge and perspective. Critical probing can overcome these difficulties in some, though not all, instances, since there are issues of principle that prohibit unique attribution of benefits to specific initiatives in many ex-post analyses. The use of cost recovery as a proxy measure of worth is reviewed.The authors point out that ex-ante appraisal of profits is not subject to the same constraints and avoids many of the pitfalls of ex-post evaluation. 相似文献
999.
“HPT has had a significant impact on the instructional design and technology field.”
Cynthia Conn is working on her Ph.D. in educational technology at the University of Northern Colorado
Jacqueline Gitonga is currently working on her Ph.D. in human resource education at the University of Illinois at Urbana-Champaign.
Her research interests are in training and development, instructional design and human performance technology. 相似文献
1000.
Katerina Bogomolova Marc A. T. M. Vorstenbosch Inssaf El Messaoudi Micha Holla Steven E. R. Hovius Jos A. van der Hage Beerend P. Hierck 《Anatomical sciences education》2023,16(1):87-98
Binocular disparity provides one of the important depth cues within stereoscopic three-dimensional (3D) visualization technology. However, there is limited research on its effect on learning within a 3D augmented reality (AR) environment. This study evaluated the effect of binocular disparity on the acquisition of anatomical knowledge and perceived cognitive load in relation to visual-spatial abilities. In a double-center randomized controlled trial, first-year (bio)medical undergraduates studied lower extremity anatomy in an interactive 3D AR environment either with a stereoscopic 3D view (n = 32) or monoscopic 3D view (n = 34). Visual-spatial abilities were tested with a mental rotation test. Anatomical knowledge was assessed by a validated 30-item written test and 30-item specimen test. Cognitive load was measured by the NASA-TLX questionnaire. Students in the stereoscopic 3D and monoscopic 3D groups performed equally well in terms of percentage correct answers (written test: 47.9 ± 15.8 vs. 49.1 ± 18.3; P = 0.635; specimen test: 43.0 ± 17.9 vs. 46.3 ± 15.1; P = 0.429), and perceived cognitive load scores (6.2 ± 1.0 vs. 6.2 ± 1.3; P = 0.992). Regardless of intervention, visual-spatial abilities were positively associated with the specimen test scores (η2 = 0.13, P = 0.003), perceived representativeness of the anatomy test questions (P = 0.010) and subjective improvement in anatomy knowledge (P < 0.001). In conclusion, binocular disparity does not improve learning anatomy. Motion parallax should be considered as another important depth cue that contributes to depth perception during learning in a stereoscopic 3D AR environment. 相似文献