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Reflection--The Story of Water

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Journal of Chemistry and Chemical Engineering 2017年第3期11卷 107-115页

作者： Marijana Magdic Vlatka Husetovic Mirna Coljak sesvetska sela primary school Lemicka 5 Sesvete Zagreb 10360 Croatia GrofJanko Draskovic primary school Vrapdanska 7 Zagreb 10000 Croatia Jelkovec primary school Dragana Plamenca 1 Zagreb Sesvete 10360 Croatia

Starting from the fact that water is quite arguably the source of life, the authors agreed to set up a project on water and name it：＂REFLECTION＂. Particular focus was placed on the following issues： water in nature, importance of water in human life, physical and chemical properties of water, protection of water in nature. The aim of the project was to make students aware of the importance of water for health as well as to help them develop a rational relationship towards drinking water. In order to find answers to the issues raised, the authors designed worksheets, PowerPoint presentations, educational games （ecological postcards, dominoes, memory games, etc.）. The authors even tried our hand at making a comic strip. Students learned about the influence of water on health, as well as about water content in particular foods. The long-term goal of the project is to introduce children to scientific approach and methodology. Through active participation and dialogue, students discover cooperative learning and acquire skills that will be beneficial to them as well as to the wider community. Working on the project, students＇ evidence that the role of an individual is a key one in building a better world. This insight helps develop their civic skills and attitudes that serve as the starting point for environmental education. The authors made numerous adaptations and implemented individual approach with the goal of training students for independent work and life according to their personal abilities in line with the principles of inclusive education. Students conduct experiments following step-by-step instructions on specially adapted worksheets. Each student gets positive feedback and experiences the joy of success that leads to the development of self-confidence and love of work and learning.

关键词： Water in nature water content in foods nature protection ecology education.

Effects of Combinatorial Expression of sela, selB and selC Genes on the Efficiency of Selenocysteine Incorporation in Escherichia coli

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Chemical Research in Chinese Universities 2013年第1期29卷 87-94页

作者： XU Ya-wei JIANG Zhi-hua MU Ying ZHANG Lei ZHAO Si-qi LIU Shu-jun WANG Cheng ZHAO Yang LU Shao-wu Key Laboratory for Molecular Enzymology and Engineering Ministry of Education Jilin University Changchun 130012 P. R. China Research Center for Analytical Instrumentation Institute of Cyber-Systems and ControlState Key Laboratory of lndustrial Control Technology Zhejiang University Hangzhou 310058 P. R. China Department of Bioengineering Jilin Agricultural Science and Technology College Jilin 132001 P. R. China Pulmonary Center School of Medicine Boston University Boston MA 02118 USA

In Escherichia coil four gene products（sela, selB, selC and selD） and a selenocysteine（Sec） insertion sequence（SECIS） are required for the correct translation of UGA codons encoding Sec. Previous studies have shown that the stoichiometry of selenoproteine mRNA and elongation factor SelB affect the efficiency of Sec incorporation. Herein lies a detailed analysis of the effects of co-expressing sela, selB and selC genes under inducible promoters on the incorporation efficiency of Sec. Over-expression of either sela or selB reduced the efficiency of Sec incorporation by 61.1% or 11.6%, respectively, compared to the over-expression of the reporter vector alone did. Concomitant over-expression ofselC with sela or selB completely reversed the reduce of the efficiency of Sec but still reduced the efficiency of the incorporation relative to that observed for expression of selC alone. Over-expression of selC gene alone under L-arabinose induction reduced the efficiency of the incorporation relative to that observed for co-expressing selC with sela and selB under the control of its endogenous promoter in the absence of L-arabinose. Co-expression of sela, selB and selC with sela or selB under the control of inducible promoters increased the effi- ciency of Sec incorporation by 69.7%. Moreover, inducing selenoprotein-related gene expression during the late exponential phase increased the efficiency of Sec incorporation by a factor of 5.4 relative to that observed for the reporter vector alone. These results suggest that the co-expression of sela, selB and selC in Escherichia coli under the control of inducible promoters is a viable and promising strategy for increasing the yields of selenoproteins.

关键词： Selenocysteine sela SelB SelC Combinatorial expression

Interpreting Dose-Response Relation for Exposure to Multiple Sound Impulses in the Framework of Immunity

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Health 2017年第13期9卷 1817-1842页

作者： Hongyun Wang Wesley A. Burgei Hong Zhou Department of Applied Mathematics and Statistics University of California Santa Cruz CA USA US Department of Defense Joint Non-Lethal Weapons Directorate Quantico VA USA Department of Applied Mathematics Naval Postgraduate School Monterey CA USA

Hearing loss is a common military health problem and it is closely related to exposures to impulse noises from blast explosions and weapon firings. In a study based on test data of chinchillas and scaled to humans (Military Medicine, 181: 59-69), an empirical injury model was constructed for exposure to multiple sound impulses of equal intensity. Building upon the empirical injury model, we conduct a mathematical study of the hearing loss injury caused by multiple impulses of non-uniform intensities. We adopt the theoretical framework of viewing individual sound exposures as separate injury causing events, and in that framework, we examine synergy for causing injury (fatigue) or negative synergy (immunity) or independence among a sequence of doses. Starting with the empirical logistic dose-response relation and the empirical dose combination rule, we show that for causing injury, a sequence of sound exposure events are not independent of each other. The phenomenological effect of a preceding event on the subsequent event is always immunity. We extend the empirical dose combination rule, which is applicable only in the case of homogeneous impulses of equal intensity, to accommodate the general case of multiple heterogeneous sound exposures with non-uniform intensities. In addition to studying and extending the empirical dose combination rule, we also explore the dose combination rule for the hypothetical case of independent events, and compare it with the empirical one. We measure the effect of immunity quantitatively using the immunity factor defined as the percentage of decrease in injury probability attributed to the sound exposure in the preceding event. Our main findings on the immunity factor are: 1) the immunity factor is primarily a function of the difference in sela (A- weighted sound exposure level) between the two sound exposure events;it is virtually independent of the magnitude of the two sela values as long as the difference is fixed;2) the immunity fac

关键词： Risk of Significant Injury Logistic Dose-Response Relation sela (A-Weighted Sound Exposure Level) Effective sela for Multiple Heterogeneous Sound Impulses Fatigue and Immunity

Life-Cycle Impact Assessment of Air Emissions from a Cement Production Plant in Cambodia

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Open Journal of Air Pollution 2022年第4期11卷 85-99页

作者： Chanto Chea Pinnara Ket Long Taing sela Kong Dalin Um Chanreaksmey Taing Chanmoly Or Srean Aun Leakhena Hang Graduate school Institute of Technology of Cambodia Phnom Penh Cambodia Faculty of Hydrology and Water Resources Institute of Technology of Cambodia Phnom Penh Cambodia Production Department Kampot Cement Co. Ltd. Kampot Cambodia Research and Innovation Center Institute of Technology of Cambodia Phnom Penh Cambodia Faculty of Chemical and Food Engineering Institute of Technology of Cambodia Phnom Penh Cambodia Department of National Council of Science Technology and Innovation Ministry of Science Technology and Innovation Phnom Penh Cambodia

Cement industrial emissions account for 32% of air pollution in Cambodia. With that in mind, we examined the environmental impact of Cambodia’s cement industry and identified ways that it could reduce air pollution. The study focused on raw material extraction and preparation, calcination, and cement preparation. Data for the life-cycle inventory were provided by the Kampot Cement Plant. Air emissions were assessed using EMEP/EEA and IPCC criteria, and the impact assessment used ReCiPe (2016). The baseline analysis revealed that calcination contributed the most air pollutants, so mitigation scenarios focused on alternative fuels only during the calcination stage of cement production: 1) 100% coal (S1);2) 93% coal and 7% biomass (S2);3) 85% coal and 15% biomass (S3);4) 70% coal and 30% biomass (S4);and 5) 50% coal and 50% biomass (S5). The results demonstrated that certain mitigation measures reduced major emissions and environmental damage. S5 had the best results, reducing CO2 by 49.97, NOx by 2.233, and SO2 by 49.333%;however, it increased PM2.5 by 19.60% and total heavy metal (Pb, Cd, Hg, As, Cr, Cu, Ni, Se, Zn) output by 28.113%. The results of the study showed reductions in serious health and environmental effects associated with climate change of 48.83%, ozone generation of 9.62%, and particulate matter formation of 28.80%. However, carcinogenic and non-carcinogenic human toxicity increased by 35.66%. Therefore, such mitigation effect would be benefit to carbon reduction target in Cambodia.

关键词： Biomass Cement Clinker Environmental Impacts European Monitoring and Evaluation Program Life Cycle Impact Assessment Midpoint Impact Endpoint Impact