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111.
Yong-Mi Kim 《The Journal of Academic Librarianship》2011,37(1):9-18
Users across academic disciplines utilize different information sources based on the resource's usefulness and relevance. This study's findings show that users from arts and sciences disciplines are much more likely to utilize university library website resources and printed materials than business users who heavily rely on commercial websites. 相似文献
112.
Kim Normann Andersen Rony Medaglia Ravi Vatrapu Helle Zinner Henriksen Robin GauldAuthor vitae 《Government Information Quarterly》2011,28(4):439-445
Assessing e-government responsiveness is one of the major gaps in the currently dominant e-government maturity models. While we have a relatively large pool of models focusing on technological and organizational integration from a supply side perspective, measures of responsiveness of e-government systems from a user perspective are still lacking. Replicating a study from New Zealand and Australia, this study explores the response time and quality of e-mail response in Danish local and central governments (N = 175). Despite that Denmark is high ranking in international benchmark studies, we find that one third of central government agencies did not respond at all, and close to 80% of the ministries provided none or incomplete answers. Local government responds faster and provides answers that are more complete and accurate than those provided by central government. Implications for e-government are discussed. 相似文献
113.
The successful encapsulation of human hepatocellular carcinoma (HepG2) cells would greatly assist a broad range of applications in tissue engineering. Due to the harsh conditions during standard chitosan fiber fabrication processes, encapsulation of HepG2 cells in chitosan fibers has been challenging. Here, we describe the successful wet-spinning of chitosan-alginate fibers using a coaxial flow microfluidic chip. We determined the optimal mixing conditions for generating chitosan-alginate fibers, including a 1:5 ratio of 2% (w∕w) water-soluble chitosan (WSC) solution to 2% (w∕w) alginate solution. Ratio including higher than 2% (w∕w) WSC solution increased aggregation throughout the mixture. By suspending cells in the WSC-alginate solution, we successfully fabricated HepG2 cell-laden fibers. The encapsulated HepG2 cells in the chitosan-alginate fibers were more viable than cells encapsulated in pure alginate fibers, suggesting that cross-linked chitosan provides a better environment for HepG2 cells than alginate alone. In addition, we found that the adhesion of HepG2 cells on the chitosan-alginate fiber is much better than that on the alginate fibers. 相似文献
114.
In this article, the authors present the fabrication of an enzyme-entrapped alginate hollow fiber using a microfluidic device. Further use of enzyme-entrapped alginate hollow fibers as a biocatalytic microchemical reactor for chemical synthesis is also deliberated in this article. To ensure that there is no enzyme leaching from the fiber, fiber surfaces were coated with chitosan. To confine the mobility of reactants and products within the porous hollow fibers the entire fibers were embedded into a transparent polydimethylsiloxane (PDMS) matrix which also works as a support matrix. A vanadium-containing bromoperoxidase enzyme isolated from Corallina confusa was used as a model enzyme to demonstrate the use of these alginate hollow-fiber reactors in bromo-oxidation of phenol red to bromophenol blue at different dye flow rates. Stability of the entrapped enzyme at different temperatures and the effect of the chitosan coating on the reaction conversion were also studied. It was observed that molecules as big as 27 kDa can be retained in the matrix after coating with chitosan while molecules with molecular-weight of around 378 Da can still diffuse in and out of the matrix. The kinetic conversion rate in this microfluidic bioreactor was more than 41-fold faster when compared with the standard test-tube procedure. 相似文献
115.
Kyung-Sun Kim Sei-Ching Joanna Sin EunYoung Yoo-Lee 《Library & information science research》2021,43(3):101104
This cohort study examined longitudinal changes in undergraduates' use of social media as information sources in academic and everyday-life contexts, covering types of social media used, purposes of use, and evaluation strategies. Web surveys were used, collecting data from 1,355 and 928 undergraduates in 2013 and 2019. The study found that students used most types of social media less in 2019 than 2013 in both contexts. Only media-sharing services bucked this downward pattern. Overall, a majority of social media types underwent changes in the top three purposes of use. The 2019 cohort used most evaluation strategies more frequently in both contexts. However, they favored simplistic strategies relying on superficial physical cues when evaluating information. Based on the findings, this study provided recommendations for information literacy education and interface design, such as covering multimedia information evaluation, leveraging various heuristics to prime careful use of social media and analytical evaluation of information. 相似文献
116.
Alghamdi Amani Khalaf H. Al Ghamdi Kholoud S. Kim Sun Young 《Journal of Science Education and Technology》2022,31(5):583-593
Journal of Science Education and Technology - It is of great importance that science educators teach COVID-19 and related pandemics to boost students’ scientific literacy. A mixed methods... 相似文献
117.
Comprehension Tools for Teachers: Reading for Understanding from Prekindergarten Through Fourth Grade 总被引:1,自引:0,他引:1
118.
The Expression of Depressive Symptomatology in Korean American Undergraduates: Sex and Generational Differences 下载免费PDF全文
Jeanett Castellanos Alberta M. Gloria Sara Cho Kim Yong S. Park 《Journal of College Counseling》2014,17(3):208-221
This study examined the influence of acculturation and perception of the university environment on the depressive symptomatology of 228 Korean American undergraduates, with a focus on sex and generational differences. Perceptions of the university environment and perceived barriers were positive predictors of depressive symptomatology in respective regression equations by sex and generation. Study limitations and counseling practice implications are discussed. 相似文献
119.
This study scrutinizes Asia Pacific Education Review (APER) that has been weathered 13 years of journey from its inception. Numerically, 504 peer-reviewed articles have been published so far, and 0.5 of impact factor has been achieved. This article recollects the history of APER, overhaul the accomplishment and shortcomings of it. Through an overview of the annually submitted and published articles, 14 domains of research area, research methods, and the demographics of contributors were examined; 30 nationalities of authors’ papers were published, and 2/3 of articles used quantitative research method. The most published domains were educational administration and policy, educational psychology and special education, and higher education; however, the most cited articles covered all research area of education impartially. This study also suggested APER’s contribution to the advancement of education research community internationally and interdisciplinarily. 相似文献
120.
Many household consumables contain volatile organic compounds(VOCs)as the active ingredient.Long term exposure to VOCs could cause various health problems,especially to the respiratory system.Graphene has attracted a lot of attention recently for its potential to be used as sensing material for VOCs.In this project we have constructed graphene/PVA composite based gas sensors for VOC detection.It was perceived that the polymer could introduce better selectivity to the sensor.Results suggest that the proposed sensor is highly sensitive to low molecular weight VOCs and that the manner in which the sensor respond to the vapour depends on the polarity or hydrophobicity of the vapour. 相似文献