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Pamela Green 《Journal of The Franklin Institute》2011,348(3):500-505
The discovery of small RNAs that can turn off genes has given us a new way to think about how genes are regulated. These molecules are present in all complex organisms and are thought to regulate upwards of 30% of human genes. Due to their small size, their discovery was surprisingly recent and was underappreciated initially. Beginning with two back-to-back papers published in 1993, the labs of Victor Ambros and Gary Ruvkun reported the first small RNA (now known as a microRNA or miRNA) and how it regulated a target mRNA in the roundworm Caenorhabditis elegans through base-pairing interactions. It took until 1999 for another report to document novel small RNAs in complex systems, when David Balcoumbe discovered similarly sized molecules, now known as small interfering RNAs or siRNAs, that were associated with shutting off or “silencing” genes in plants. A frenzy of reports on small RNAs and their roles in turning off genes ensued with many researchers including Ambros, Ruvkun, and Baulcombe prominently participating. Almost instantly it became clear that small RNAs were not a quaint oddity exclusive to the worm, and molecular biology was never the same. Now we know that these molecules are critical for normal growth and development, are associated with cancer and other diseases, and have tremendous applied potential to improve agriculture and human health. 相似文献
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Gary W. Green 《Journalism Practice》2017,11(6):721-739
This article examines how one Central Florida newspaper used emerging media technologies to communicate and engage better with a newly active audience during its coverage of two high-profile court trials. Through a series of in-depth interviews with participating journalists, the author demonstrates how the Orlando Sentinel disrupted traditional newsgathering and dissemination methods during reporting of the Casey Anthony and George Zimmerman trials, and in doing so, challenged long-standing gatekeeping media theories and exemplified emerging participatory journalism models. Findings show that audience demands for live and continuous information throughout the development of the Casey Anthony and George Zimmerman stories and resulting court proceedings were a driving force in changing outdated journalism paradigms that led to the adaptation of a new norm by the Orlando Sentinel newsroom and journalists. 相似文献
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Ami Flowers Staples Ti’Era Worsley Gary T. Green John P. Carroll 《The Journal of environmental education》2013,44(3):208-222
ABSTRACTThis study used a combination of surveys and drawing-based metrics to evaluate whether integration of art-based activities into EE camp programing could enhance environmental orientations of diverse youth ages 6–12 (n?=?285) in Athens, GA, USA. Compared to a control group, art-based EE had a positive effect on children’s eco-awareness and environmental knowledge. However, effects of the art-based EE were comparable to those observed for a conventional EE summer camp. Interactions between the treatment and demographic variables (e.g., gender, age, race/ethnicity) were minimal, suggesting that both types of EE programing worked well for different groups of youth. Results highlight the potential value of art in EE research and practice. 相似文献
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Development of an Instrument to Assess Student Opinions of the Quality of Distance Education Courses
Beth Hensleigh Chaney James M. Eddy Steve M. Dorman Linda Glessner B. Lee Green Rafael Lara-Alecio 《The American journal of distance education》2013,27(3):145-164
This study describes the development of a learning process of genetic counseling and basic genetics using an e-learning model and its application to a group of psychologists in the state of Parana in southern Brazil. The aim was to analyze the impact on the increase of knowledge in the presented subjects and the possibility of applying this project on a larger scale. The results of two observations were compared. The observations consisted of scores on the same exams, applied before and after taking the course. Results indicated that the remote education process is indeed a viable alternative for genetic counseling education and is validated for application in large scale together with Centers for Family Health Care Assistance of the Brazilian Ministry of Health Care. 相似文献