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Yasmim R. Jaconiano Juliana S. Goulart Jos C. Barros Ricardo C. Michel 《Journal of Food Science Education》2021,20(1):26-30
It began in 1869, and today we have 118 elements listed in the Periodic table, thanks to Mendeleev's work. Carbon, hydrogen, oxygen, and nitrogen are elements presented in many organic compounds. Some of them can exhibit photophysical and photochemical properties. Herein, we proposed an easy to make an experiment in chemistry classes to connect both subjects, periodic table and photochemistry, through periodic tables made of fluorescent jellies. A sheet of PET‐G was heated and put over the periodic table mold made in a 3D‐printing to produce the form used in this work. Quinine and vitamin B2, from tonic water and vitamin supplement, respectively, were the fluorescent compounds selected to be in the gelification process to give the jelly fluorescence. The light source was a black light lamp. This work allowed for the discussion of photophysics and photochemistry concepts, 3D‐printing process, gelification, and the International Year of the Periodic Table of Chemical Elements—IYPT2019—with undergraduate students without the use of expensive reagents or equipment. 相似文献
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Sophie Goldingay Greer Lamaro Haintz Juliana Ryan Danielle Hitch Susie Macfarlane 《高等教育研究与发展》2017,36(5):975-988
The marketisation of higher education (HE) has created a number of tensions and ideological dilemmas that may influence how academics see their roles and teaching practices. This paper explores how academics in the discipline of social work (who were also in leadership roles) perceive their roles and identities and manage the tensions and dilemmas that arise for them as teachers in the current HE environment. Unless the tensions and dilemmas are articulated, it is not possible to understand and manage their impact on academics. This may lead to the loss of quality learning experiences for students and lower workplace satisfaction. This paper addresses the research question: were there ideological dilemmas experienced by social work academics in the current environment and if so, what subject positions did they adopt in response to these? A discursive psychology approach was used to answer this question. Data showed a range of ideological dilemmas represented by each of the different subject positions adopted. The paper concludes with questions for readers to consider, generating ideas for transferring understanding of these ideological dilemmas into positive action within the workplace. 相似文献
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Katie Chau Aminata Traoré Seck Venkatraman Chandra-Mouli Joar Svanemyr 《Sex education》2016,16(5):503-519
In Senegal, school-based sexuality education has evolved over 20 years from family life education (FLE) pilot projects into cross-curricular subjects located within the national curriculum of primary and secondary schools. We conducted a literature review and semi-structured interviews to gather information regarding the scale and nature of FLE scale-up. Data were analysed using the ExpandNet/WHO framework, conceptualising scale-up from a systems perspective as composed of interrelated elements and strategic choices. Key enabling factors that facilitated the scale-up of FLE included (1) programme clarity, relevance and credibility; (2) programme adaptability to young people’s evolving sexual and reproductive health priorities; (3) the engagement of a strong and credible resource team comprising government and civil society agencies; (4) a favourable policy environment; and (5) deliberate strategic choices for horizontal and vertical scale-up. Barriers included sociocultural conservatism that creates resistance to content areas deemed to be culturally sensitive, resulting in partial scale-up in terms of content and coverage, as well as structural barriers that make it difficult to find space in the curriculum to deliver the full programme. Lessons learned from Senegal’s experience can strengthen efforts to scale-up school-based sexuality education programmes in other culturally conservative low- and middle-income countries. 相似文献
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The use of non-English Web search engines has been prevalent. Given the popularity of Chinese Web searching and the unique characteristics of Chinese language, it is imperative to conduct studies with focuses on the analysis of Chinese Web search queries. In this paper, we report our research on the character usage of Chinese search logs from a Web search engine in Hong Kong. By examining the distribution of search query terms, we found that users tended to use more diversified terms and that the usage of characters in search queries was quite different from the character usage of general online information in Chinese. After studying the Zipf distribution of n-grams with different values of n, we found that the curve of unigram is the most curved one of all while the bigram curve follows the Zipf distribution best, and that the curves of n-grams with larger n (n = 3–6) had similar structures with β-values in the range of 0.66–0.86. The distribution of combined n-grams was also studied. All the analyses are performed on the data both before and after the removal of function terms and incomplete terms and similar findings are revealed. We believe the findings from this study have provided some insights into further research in non-English Web searching and will assist in the design of more effective Chinese Web search engines. 相似文献
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Shunbo Li Ming Li Kristelle Bougot-Robin Wenbin Cao Irene Yeung Yeung Chau Weihua Li Weijia Wen 《Biomicrofluidics》2013,7(2)
Integrating different steps on a chip for cell manipulations and sample preparation is of foremost importance to fully take advantage of microfluidic possibilities, and therefore make tests faster, cheaper and more accurate. We demonstrated particle manipulation in an integrated microfluidic device by applying hydrodynamic, electroosmotic (EO), electrophoretic (EP), and dielectrophoretic (DEP) forces. The process involves generation of fluid flow by pressure difference, particle trapping by DEP force, and particle redirect by EO and EP forces. Both DC and AC signals were applied, taking advantages of DC EP, EO and AC DEP for on-chip particle manipulation. Since different types of particles respond differently to these signals, variations of DC and AC signals are capable to handle complex and highly variable colloidal and biological samples. The proposed technique can operate in a high-throughput manner with thirteen independent channels in radial directions for enrichment and separation in microfluidic chip. We evaluated our approach by collecting Polystyrene particles, yeast cells, and E. coli bacteria, which respond differently to electric field gradient. Live and dead yeast cells were separated successfully, validating the capability of our device to separate highly similar cells. Our results showed that this technique could achieve fast pre-concentration of colloidal particles and cells and separation of cells depending on their vitality. Hydrodynamic, DC electrophoretic and DC electroosmotic forces were used together instead of syringe pump to achieve sufficient fluid flow and particle mobility for particle trapping and sorting. By eliminating bulky mechanical pumps, this new technique has wide applications for in situ detection and analysis. 相似文献
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Ana Paula Da Silva Azevedo Kátia Brandina Roberto Bianco Vitor Henrique De Oliveira Juliana Roque De Souza Bruno Mezencio 《Journal of sports sciences》2013,31(9):929-935
Abstract Twelve participants ran (9 km · h?1) to test two types of running shoes: replica and original shoes. Ground reaction force, plantar pressure and electromyographic activity were recorded. The shoes were tested randomly and on different days. Comparisons between the two experimental conditions were made by analysis of variance (ANOVA) test (P ≤ 0.05). The time to first peak, loading rate of the first peak and impulse of the first 75 ms of stance were significantly different between the shoes (P ≤ 0.05), revealing an increase of impact forces for the replica shoes. The peak plantar pressure values were significantly higher (P ≤ 0.05) when wearing replica shoes. During running, the contact area was significantly smaller (P ≤ 0.05) for the replica shoe. The electromyographic activity of the analysed muscles did not show changes between the two shoes in running. These findings suggest that the use of replica running shoes can increase the external load applied to the human body, but may not change the muscle activity pattern during locomotion. This new mechanical situation may increase the risk of injuries in these movements. 相似文献
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