• Journal of Life Science
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• v.26 no.1
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• pp.34-41
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• 2016

Black chokeberries (scientific name Aronia melanocarpa) have been reported to have major effects due to anti-oxidant, anti-inflammatory, and anti-cancer capabilities. In this study, we investigated the anti- wrinkle effects of A. melanocarpa, including collagenase inhibition effects and their molecular biological mechanisms, such as oxidative stress-induced matrix metalloproteinase (MMP), mitogen-activated protein (MAP) kinase, and activator protein (AP)-1 expression and/or phosphorylation. In collagenase inhibition activity, the ethyl acetate fraction of black chokeberry (AE) was 77.2% at a concentration of 500 μg/ml, which was a significant result compared to that of Epigallocatechin gallate (positive control, 83.9% in 500 μg/ml). In the reactive oxygen species (ROS) assay, the AE produced 78% of ROS in 10 μg/ml and 70% of ROS in 75 μg/ml, which was a much lower percentage than the ROS production of H₂O₂-induced CCRF S-180II cells. In the MTT assay, cell viability was increased dose-dependently with AE in H₂O₂-induced cells. In protein expression by western blot assay, the AE suppressed the expression and phosphorylation of MMPs (MMP-1, -3, -9), MAPK (ERK, JNK, and p38), and AP-1 (c-Fos and c-Jun), and expressed the pro-collagen type I in H₂O₂-induced cells. These results suggest that black chokeberries have anti-wrinkle and collagen-production effects, and they may be used in applications for material development in the functional food and cosmetic industries.

• Journal of The Korean Association For Science Education
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• v.20 no.4
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• pp.582-598
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• 2000

There are many bioethical issues in line with the rapid advance of biology. In this situation, it is important for students to make a rational decision on value problem. In this study 'value inquiry in biology education' is defined as 'the process of rational value judgement and wise decision-making in the biology-related value problem' and the model was developed. To develop the model, value inquiry models were reviewed. Value clarification model is helpful for the formation of the personal value as the process of individual value inquiry, but it isn't helpful for clarifying the value conflicts. Value analysis model focuses on the rational solution of value problem through the logical procedure. But it has the limitations that overemphasizing the logical and systematic aspects results in devaluating students' affective aspects. So it is necessary to coordinate psychological and logical aspects of value inquiry. In this regard, the model was developed, including identifying and clarifying value problem, understanding biological knowledge related to conflict situation, considering on the related persons, searching for alternatives, predicting the consequences of each alternative, selecting the alternative, evaluating the alternative, and final value judgement and affirming it. The educational objectives of value inquiry were selected in consideration of the ability to carry out the steps of the developed model. And the selected contents were animal duplication, test-tube baby, genetic engineering, growth hormone injection problem, brain death, organ transplant, animal to be experimented and were organized on the basis of the 6th and the 7th science curriculum. And the suitable instructional models for the value inquiry education were selected: bioethical value clarification decision-making model, group presentation according to the value analysis model, role play and debate, and discussion through web forum. And the interview was considered to be suitable to evaluate the students' value inquiry ability and the rubric was made to evaluate the attainment of the educational objectives for value inquiry.

• Journal of The Korean Association For Science Education
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• v.23 no.1
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• pp.35-46
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• 2003

Problem solving ability, having been thought as one of the most important goals of science education is also a primary task for the current education. Indeed, the students' problem solving ability has shown almost no actual progress, despite our long accumulated science education. Under this circumstances, cooperative learning, a way to grow students' positive inter-dependence and problem solving ability in the basis of their active participation and discussion, was proposed as an effective teaching method. But, results have not consistently shown the advantage of cooperative learning over traditional learning for promoting academic achievement in science. Studies have consistently shown greater effectiveness on affective aspects. But, relatively few have focused on biology in Korea. The purpose of this study was to examine the effects of cooperative learning on the achievement and attitude of high school biology students. The pretest-posttest control group design was applied. The sample consisted of 50 11th-grade female students in experimental group(cooperative learning Student Team Achievement Division model) and 50 students in control group(traditional learning). Students in both groups recieved identical content instruction on the unit 'II. Methabolism'. These groups were treated for 13 hours during 5 weeks. Achievement data were collected using a 24-item multiple-choice test(content validity= .85). Science attitude was measured by an instrument which adapted by Kim In Hee(1994). The instrument(Cronbach $\alpha$=.89) included 40 items in four subscales: attitude toward science, social meaning of science, attitude toward science class, and scientific attitude. An analysis of covariance (ANCOVA) was used as the data analysis procedure. For the achievement data, no significant difference exists between the cooperative and traditional groups (p> .05). But, cooperative learning was effective in low-ability students(p < .05). For the science learning attitude data, cooperative learning was more effective than the traditional one(p< .05). Students in the cooperative group acheived better than those in traditional one especially in the subscale of attitude toward science class. There was no meaningful difference of the two methods in both high and average ability students, while cooperative learning was more effective than the traditional one in low ability students(p<.05).

• Journal of The Korean Association For Science Education
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• v.24 no.5
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• pp.851-868
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• 2004

The main purposes of this study is to develop a web-based STS biology instruction program (WB-STS) for the scientifically gifted students. The specific main research questions were as follows; 1. How can the WB-STS for biology education be developed and what are the primary components involved in it? 2. Is there any proper validity for developed the WB-STS in biology education? To solve the above mentioned problems, several procedures were applied. First, in order to develop WB-STS for the scientifically gifted students, NCISE, Renzulli' s Enrichment Triad Model and the Iowa Chautauqua program's main characteristics were analyzed systematically and the principles and general process for constructing WB-STS were examined. Additionally, the needs of students and the goals of Biology education were identified thoroughly. And then all these ideas were embodied in an agenda for constructing WB-STS. Second, to analyse the validity and utility of developing WB-STS, a questionnaire was developed and submitted to seven specialists and a group of twenty students who would participate in the experiment later. The main results of study are summarized below: First, WB-STS appeared to be successfully constructed based on Renzulli' s Enrichment Triad Model and the Iowa Chautauqua program. Its main features are that it was made emphasizing a learner-centered approach and constructive learning. It is composed of five steps: Scientific theme selection -${\rightarrow}$Exploration ${\rightarrow}$ Concept & Principle Check ${\rightarrow}$ Finding Solution ${\rightarrow}$ Action. Second, seven specialists and a group of students assessed the developed WB-STS's validity and utility with a questionnaire, the results appeared satisfactory. Students showed high interest in WB-STS and gave a positive evaluation of WB-STS.

• Journal of The Korean Association For Science Education
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• v.36 no.4
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• pp.591-606
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• 2016

The purpose of this study is to develop the argumentation program to build scientific concepts on natural selection for science-gifted elementary students and to know how to implement this program. For this study, nine key concepts about natural selection such as the overproduction of offspring, limited resources, population stability, competition, variation, heredity of variation, differential survival, change of the population and speciation were selected through the literature study. The programs were developed by learning cycle instructional model. Argument writings and discourses have been collected, analyzed and compared before and after the program. Two questionnaires to compare pre and post concept change consist of multiple choice questionnaire and open-ended response question were developed and applied to 19 science-gifted elementary students. Sufficiency of the explanation and conceptual quality of the explanation were used to assess the quality of their arguments before and after the program. Discourse and visual models collected from the highest and lowest group about score improvement were compared. The scores of the gifted statistically improved significantly in multiple choice questionnaire. Students' alternative conceptions about natural selection at the beginning of the program decreased and changed scientifically after the program. Visual models drawn by the students supported the results as well. This study asserts that elementary science-gifted students are able to explain evolutionary perspectives about organism change and use the key concepts of natural selection. The study means that evolutionary perspective is possible to be reflected in elementary science curriculum for the gifted.

• Journal of The Korean Association For Science Education
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• v.35 no.2
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• pp.313-323
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• 2015

The purpose of this study is to investigate the cognitive process of student's modeling on a modeling-emphasized argument-based general chemistry experiment. The participants were twenty-one freshman students. Six topics were carried out during the first semester and semi-structured interview was implemented at the end of the semester. Semi-structured interview questions were used to elicit elements of effective model, modeling strategies, difficulties that students have experienced during modeling, and resolving the difficulties that students have experienced during modeling. All student interview data were collected and transcribed. The results of this study are summarized as follows: (1) Elements of effective model were considered to be visual expression, persuasive explanation, and rhetorical structure. (2) Modeling strategies included arranging important keywords or writing the outline, and during the modeling process, students used various data, suggested data after reconstructing, suggested definitions and explanations of core concepts, used meta-cognition, and considering rhetorical structure. (3) Difficulties students have experienced during modeling could be categorized as lack of modeling strategy and understanding. (4) Resolving difficulties students have experienced during modeling could be categorized as modeling strategy and understanding. Students learn the strategy by feedback, modeling experience, evaluation of experimental report, models which they constructed previously and references, and the understanding of contents were achieved through arguments which occurred during classes and during the process of writing the experimental reports. These results suggest that when using modeling in teaching and learning, the argument-based learning strategy can be effective in enhancing students' modeling by helping them to understand meta-modeling with scientific concepts.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.7
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• pp.846-853
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• 2016

This study prioritizes Noxious Liquid Substances (NLS) transported by sea via a risk-based database containing 596 chemicals to prepare against NLS incidents. There were 158 chemicals transported in Korean waters during 2014 and 2015, which were prioritized, and then chemicals were grouped into four categories (with rankings of 0-3) based on measures for preparedness against incident. In order to establish an effective preparedness system against NLS spill incidents on a national scale, a compiling process for NLS chemicals ranked 2~3 should be carried out and managed together with an initiative for NLS chemicals ranked 0-1. Also, it is advisable to manage NLS chemicals ranked 0-1 after considering the characteristics of NLS specifically transported through a given port since the types and characteristics of NLS chemicals relevant differ depending on the port. In addition, three designated regions are suggested: 1) the southern sector of the East Sea (Ulsan and Busan); 2) the central sector of the South Sea (Gwangyang and Yeosu); and 3) the northern sector of the West Sea (Pyeongtaek, Daesan and Incheon). These regions should be considered special management sectors, with strengthened surveillance and the equipment, materials and chemicals used for pollution response management schemes prepared in advance at NLS spill incident response facilities. In the near future, the risk database should be supplemented with specific information on chronic toxicity and updated on a regular basis. Furthermore, scientific ecotoxicological data for marine organisms should be collated and expanded in a systematic way. A system allowing for the identification Hazardous and Noxious Substances (HNS) should also be established, noting the relevant volumes transported in Korean waters as soon as possible to allow for better management of HNS spill incidents at sea.

• Journal of the Korean Dietetic Association
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• v.8 no.3
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• pp.269-279
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• 2002

To investigate the change of perception after weight management education in elementary, middle and high school students, a survey was conducted. Same questionnaire was administered twice, before and after weight management education, to 426 students at 9 schools in Seoul area. The mean height, weight and body mass index were 145.5$\pm$8.0cm, 40.0$\pm$8.3kg, 18.6$\pm$3.0 for elementary school students, 160.1$\pm$5.2cm, 50.2$\pm$7.3kg, 19.5$\pm$2.4 for middle school students, and 162.2$\pm$5.0cm, 52.2$\pm$6.4kg, 19.8$\pm$2.3 for high school students, respectively. Before education, their preferred weight and perceived healthy weight was 35.4kg and 37.0kg among elementary school students, 44.8kg and 46.5kg among middle school students, and 47.3kg and 48.9kg among high school students, respectively. Differences between their present body weight and their preferred weight and/or perceived healthy weight appeared to be 4.5kg and 2.9kg in elementary school students, 5.6kg and 4.0kg in middle school students, and 5.1kg and 3.3kg in high school students, respectively. After administering education, the differences decreased to 2.5kg and -0.2kg in elementary school students, 4.2kg and 2.7kg in middle school students, and 4.3kg and 2.0kg in high school students, respectively (p<0.01). And their perception on own body shape was investigated using 5 point scale ('too lean' to 'too fat', 1 to 5) before and after education. The mean values changed from 3.1 to 2.8 in elementary school students, from 3.3 to 3.0 in middle school students, and from 3.4 to 3.2 in high school students (p<0.01). Their satisfaction with own body weight was monitored using 5 point scale ('very satisfied' to 'very unsatisfied', 1 to 5), also. The mean values changed from 3.0 to 2.7 in elementary school students, from 3.6 to 3.2, in middle school students, and from 3.8 to 3.4 in high school students (p<0.01). In the evaluation of their nutrition knowledge about weight control using 10 item quiz, before and after education, the mean quiz score was changed from 6.3 to 7.0 in elementary school students, from 7.0 to 7.9 in middle school students, and from 7.5 to 8.1 in high school students (p<0.01). In summary, nutrition education on weight management improved the subject's perception on perceived healthy weight and own body shape, and satisfaction with present body weight. This result suggests that nutrition education program should incorporate strategies to change incorrect beliefs and knowledge regarding weight control. Onto this, weight control education for students should start from their early age, be repeated periodically and consistently, and focus on the harmful effects of excessive weight loss and information on the practical and scientific ways of weight management.

• Journal of Life Science
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• v.24 no.3
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• pp.329-335
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• 2014

Sophora flavescens, Glycyrrhiza uralensis and Dictamnus dasycarpus have been widely used in folk medicine for several inflammatory disorders in Korea and China. In this study, we compared the anti-inflammatory effects of the ethanol extracts of S. flavescens (EESF), G. uralensis (EEGU) and D. dasycarpus (EEDS), and their mixtures (medicinal herber mixtures, MHMIXs) on production of inflammatory mediators and cytokines in lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages. Our data indicated that treatment with EESF, EEGU and EEDD significantly inhibited the excessive production of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) in LPS-stimulated RAW 264.7 cells. The ethanol extracts and MHMIXs also attenuated the production of pro-inflammatory cytokines, including interleukin-$1{\beta}$ ($IL-1{\beta}$) and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) by suppressing their protein expression, respectively. Interestingly, MHMIX-1, which basic ingredients are EESF, EEGU and EEDS in the proportion 3:1:1, more safely and effectively inhibits the LPS-induced inflammatory status in LPS-stimulated RAW 264.7 macrophages compared to ethanol extracts of each medicinal herb and other MHMIXs without causing any cytotoxic effects. Our study provides scientific evidence to support that a berbal mixture, MHMIX-1 may be useful in the treatment of inflammatory diseases by inhibiting inflammatory regulator responses in activated macrophages.

• Journal of Conservation Science
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• v.32 no.4
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• pp.579-588
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• 2016

This study analyzed nonmetallic inclusions in iron swords with a ring pommel excavated in the Ipbuk-dong, Suwon. Scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS) was used to estimate the iron-making temperature, and we compared the oxide with $SiO_2$ to investigate the heat-treatment technology in the production of iron swords with a ring pommel by investigating the artificial insertion of a slag former and the metallurgical structure. From the wustite observed in most of the specimens, it is judged that these swords were produced by heating and forging iron smelted at a low temperature using the solid reduction method. In addition, judging from the partial presence of $P_2O_5$, it is assumed that they were smelted directly with natural ore, not calcined. From the ratios of $CaO/SiO_2$ and $TiO_2/SiO_2$, it is judged that the raw material for iron-making was iron ore and that a calcareous slag former was not artificially inserted. The structure of the blade part on the front end was pure iron. From the high carbon content of the blade part on the ring pommel and the formation of a martensitic structure and pearlite colony, it is judged that they were tempered after carburizing and that the back, handle part, and ring pommel were unintentionally carburized. Judging from the structure of these specimens, it was noted that they were produced by applying artificial partial heat-treatment technology. This study attempted to present a more scientific analysis by using the method of interpretation through component analysis of nonmetallic inclusions appearing in one relic by the ratio of the oxide divided by $SiO_2$. It is judged that reinterpreting the arguments by the results of the existing analysis and research in this way can obtain different interpretations.