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991.
Darren S. Miller Anne Michelle Parsons John Bresland Paul Herde Duc Minh Pham Angel Tan Hung-yao Hsu Clive A. Prestidge Tim Kuchel Rezaul Begg Syed Mahfuzul Aziz Ross N. Butler 《Journal of Zhejiang University. Science. B》2015,16(7):586-592
Understanding the ecology of the gastrointestinal tract and the impact of the contents on the host mucosa is emerging as an important area for defining both wellness and susceptibility to disease. Targeted delivery of drugs to treat specific small intestinal disorders such as small bowel bacterial overgrowth and targeting molecules to interrogate or to deliver vaccines to the remote regions of the small intestine has proven difficult. There is an unmet need for methodologies to release probes/drugs to remote regions of the gastrointestinal tract in furthering our understanding of gut health and pathogenesis. In order to address this concern, we need to know how the regional delivery of a surrogate labeled test compound is handled and in turn, if delivered locally as a liquid or powder, the dynamics of its subsequent handling and metabolism. In the studies we report on in this paper, we chose 13C sodium acetate (13C-acetate), which is a stable isotope probe that once absorbed in the small intestine can be readily measured non-invasively by collection and analysis of 13CO2 in the breath. This would provide information of gastric emptying rates and an indication of the site of release and absorptive capacity. In a series of in vitro and in vivo pig experiments, we assessed the enteric-protective properties of a commercially available polymer EUDRAGIT®L100-55 on gelatin capsules and also on DRcaps®. Test results demonstrated that DRcaps®coated with EUDRAGIT®L100-55 possessed enhanced enteric-protective properties, particularly in vivo. These studies add to the body of knowledge regarding gastric emptying in pigs and also begin the process of gathering specifications for the design of a simple and cost-effective enteric-coated capsule for delivery of acid-labile macromolecules to the small intestine. 相似文献
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Lise Stengaard Hansen Monika Åkerlund Terje Grøntoft Morten Ryhl-Svendsen Anne Lisbeth Schmidt Jan-Erik Bergh Karl-Martin Vagn Jensen 《Journal of Cultural Heritage》2012,13(1):22-27
The brown carpet beetle Attagenus smirnovi, Zhantiev 1973 (Coleoptera: Dermestidae) is an important pest of objects of organic origin in museums of cultural and natural history in Europe. Future climate changes are expected to lead to increasing temperatures, which will affect the pest status of this species. In the present study a laboratory investigation was conducted to elucidate the effect of temperature and humidity on the amounts of organic material consumed by larvae of A. smirnovi. In the case of new and old skin, consumption was approximately twice as high at 28 °C compared to 20 °C. Wool was consumed in the greatest amounts: 169 mg of wool was consumed in three months by 30 A. smirnovi larvae. The expected future climate changes in Scandinavia are assumed to lead to higher temperatures in museums and stores where climate is not regulated. Updated data on the present distribution of A. smirnovi in Europe show that it is widespread and common, also in regions with a climate that does not support its survival out of doors. Thus, dispersal of this pest probably only rarely occurs by flight, but usually with human activity. Due to the widespread distribution of A. smirnovi, it is likely that damages in museums and collections in Scandinavia due to this pest will increase as climate changes come into effect. 相似文献
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Danielle Lester Gregory J. Skulmoski Darren P. Fisher Vishal Mehrotra Iris Lim Alexander Lang Justin W. L. Keogh 《British journal of educational technology : journal of the Council for Educational Technology》2023,54(6):1748-1770
While gamification and game-based learning have both been demonstrated to have a host of educational benefits for university students, many university educators do not routinely use these approaches in their teaching. Therefore, this systematic review, conducted using the PRISMA guidelines, sought to identify the primary drivers and barriers to the use of gamification and game-based learning by university educators. A search of multiple databases (Web of Science, Scopus and EBSCO (Business Source Complete; ERIC; Library, Information Science & Technology Abstracts)) identified 1330 articles, with 1096 retained after duplicates were removed. Seventeen articles (11 quantitative, two mixed-methods and four qualitative) were included in the systematic review. The primary drivers described by the educators that positively influenced their gamification and game-based learning usage were their beliefs that it encourages student interactions and collaborative learning; provides fun and improves engagement; and can easily be used by students. Alternatively, the university educators' major barriers included a lack of time to develop gamification approaches, lack of proven benefits and classroom setting issues. Many of these and other less commonly reported drivers and barriers can be categorised as attitudinal, design-related or administrative in nature. Such categorisations may assist university educators, teaching support staff and administrators in better understanding the primary factors influencing the utilisation of gamification and game-based learning and develop more effective strategies to overcome these barriers to its successful implementation.
Practitioner notes
What is already known about this topic
- Gamification and game-based learning may have many benefits for university students.
- The majority of university educators do not routinely use gamification and game-based learning in their teaching.
What this paper adds
- University educators' major drivers that positively influence the use of gamification and game-based learning include their perceptions that it encourages student interactions and collaborative learning, provides fun and improves engagement and can easily be used by students.
- University educators' major barriers that negatively influence the use of gamification and game-based learning include their perceptions of a lack of time to develop gamification approaches, lack of proven benefits and classroom setting issues.
- These drivers and barriers may be classified as attitudinal, design-related and administrative, with these categories providing a useful way for universities to develop strategies to better support educators who wish to use these approaches in their teaching.
Implications for practice and policy
- Attitudinal factors such as university educators' intention to use gamification and game-based learning are influenced by a host of their perceptions including attitude, perceived usefulness and ease of use.
- A range of design-related and administrative barriers may need to be overcome to increase the use of gamification and game-based learning in the university sector.
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Anne van Goethem Anne van Hoof Bram Orobio de Castro Marcel Van Aken Daniel Hart 《Child development》2014,85(6):2114-2130
This meta‐analysis assessed the effect of community service on adolescent development and the moderation of this effect by reflection, community service, and adolescent characteristics to explicate the mechanisms underlying community service effects. Random effects analyses, based on 49 studies (24,477 participants, 12–20 years old), revealed that community service had positive effects on academic, personal, social, and civic outcomes. Moderation analyses indicated that reflection was essential; the effect for studies that include reflection was substantial (mean ES = .41) while community service in the absence of reflection yielded negligible benefits (mean ES = .05). Effects increased when studies include more frequent reflection and community service, reflection on academic content, and older adolescents. These findings have implications for understanding and improving community service. 相似文献
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