• Korean journal of food and cookery science
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• v.21 no.3 s.87
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• pp.290-300
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• 2005

Increased sanitation management of foodservice establishments is required because most of the reported foodborne-disease outbreaks were in the foodservice industry. The purpose of this study was to determine the important control points for good sanitation. In this study, we inspected twenty foodservice establishments in Seoul, Kyunggi, Kyungnam with a self-developed monitoring tool. These foodservice establishments included secondary schools, universities, and industries. Six of them had appointed as the HACCP-certified establishments from the Korea Food and Drug Administration. The inspection was conducted from June to August in 2002. The inspection tool consisted of nine dimensions and sixty-five items. The dimensions were 'personal sanitation', 'supply of raw food', 'food storage', 'handling of raw food and ready-to-eat', 'cleaning and sterilization', 'waste control', 'pest control', and 'control of establishment and equipment' The highest possible score of this inspection tool is 105 points. Statistical data analysis was completed using the SPSS Package(11.0) for descriptive analysis Kruskal-Wallis. The score for the secondary schools (83.6 points) was higher than for the others and number of in compliance item was 50.9 on average. Therefore, we concluded that the secondary schools' sanitation condition was good. The foodservice establishments acquired HACCP certification was 89.7 points, which was significantly higher than that of establishments not applying foodservices in total score. Instituting the HACCP system in a foodservice is very effective for sanitation management. Many out of the compliance observations were found in the dimensions of 'waste control', 'control of establishment and equipment', and 'supply of raw food' 'Clean condition of refrigerator' item was $65\%$ out of the compliance that was the highest percent in this study. 'Notify and observance of heating/reheating temperature' was $45\%$ out of compliance. Items which were over $30\%$ out of compliance were 'sterilization of knifes and chopping boards in cooking', 'education of workers', 'maintain refrigerator temperature blow $5^{\circ}C$', and 'countermeasure of infection workers' In the results, most of the foodservice establishments were poorly managed in temperature control and cross-contamination. The important control points revealed in this study were preventing contamination, cooking temperature compliance, management of raw food and refrigerator. Therefore foodservice establishments should pay attention to education and training about important control points. The systematic sanitation management monitoring tool developed in this study can be effectively applied for conducting self-inspection and improving the sanitary conditions of their own foodservice operations.

• Journal of The Korean Association of Information Education
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• v.21 no.1
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• pp.41-55
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• 2017

The physical computing education, as the emerging field, is a form of education that helps learners to develop the attitude of scientific inquiry by developing meaningful and creative output through the integration of hardware and software elements. Based on the literature, the authors of the study used science experience, school support and learning flow as the variables that predict the outcome variable which is the attitude of scientific inquiry. The authors collected data from 64 fourth and sixth graders who studied physical computing at an institution for the gifted and talented in Korea and then analyzed them using descriptive statistics, correlation, multiple regression and simple mediation analysis methods. As a result, science experience and learning flow significantly predicted the attitude of scientific inquiry. In addition, learning flow mediated the relationship between science experience and the attitude of scientific inquiry, and the relationship between school support and the attitude of scientific inquiry. Based on these results, the authors propose that to promote the attitude of scientific inquiry in physical computing education, strategies must be implemented for improving science experience, school support and learning flow in instructional design.

• Journal of the Korean earth science society
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• v.38 no.4
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• pp.303-320
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• 2017

Purpose of this study is understanding of group modeling process focusing on constraints with geological field trip applied on social-construction of scientific model. This study was carried out on 12 students of 3 groups who participate in the study 'S' gifted education center. Students were conducted to theme of 'How was formation of Mt. Gwanak?' on 2 field trip classes and 3 modeling classes. Semi-structured interviews, all discourse of field trip and modeling classes, records of personal and group activity were analyzed to constraints based on theoretical background proposed by Nersessian (2008). Results as follows. First, sources of constraints are scientific knowledge, contents observed by students during field trips and additional materials things to be explained by model during modeling class with geological field trip applied on social-construction of scientific model. Second, there are 3 types of constraints to affect making group modeling. It is that shared constraint which used commonly by all the group members. It called selected constraint that used during the initial modeling and later were reflected on for use in the group modeling. And it is that generated constraints, which were not in the initial modeling but were used later in the group modeling. This study suggests that not only the constraints can help to understand of making group model through how they used but also show that example of learning with geological field trip on social-construction of scientific model to contribute school science.

• Journal of Science Education
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• v.36 no.2
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• pp.216-234
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• 2012

This study examined the characteristics of verbal interactions presented in TS activities with different tasks' openness levels by the cognitive levels of students through the implementation of TS program to 14 fifth graders in gifted class. Results of this study revealed that the open-type TS activities showed higher percentages of verbal interactions than the guiding-type TS activities showed and that the higher the open level of tasks was, the more high-level verbal interactions occurred. These results were showed in almost all subcomponents of verbal interactions. The results according to the students' cognitive levels showed that the higher the cognitive level of students was, higher frequency of interactions, high-level verbal interactions and a variety of verbal interactions occurred. The influence of both cognitive level of students and the task's openness on verbal interactions among students seemed to be interactive, however. In guiding-type activities, the percentage of high-level verbal interactions was not high although the cognitive level of students was high. And students in low level of cognition showed far lower frequency of interactions and their percentage of high-level verbal interactions was low even though the openness of the tasks was high. The results of this study meant that although open-type activities drew higher level verbal interactions by stimulating students' thought, the effects would be limited owing to their low cognitive level. Based on these findings, an implication was suggested that it is important to design instructional strategies and adjust openness level of TS activities to students' cognitive level so as to stimulate the thinking of students in lower cognitive level and to highten their engagement in activities.

• Communications of Mathematical Education
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• v.25 no.2
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• pp.473-495
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• 2011

Across the secondary school, students deal with the algebraic conditions like as identity, inverse, commutative law, associative law and distributive law. The algebraic structures, group, ring and field, are determined by these algebraic conditions. But the conditioning of these algebraic structures are not mentioned at all, as well as the meaning of the algebraic structures. Thus, students is likely to be considered the algebraic conditions as productions from the number sets. In this study, we systematize didactically the meanings of algebraic conditions and algebraic structures, considering connections between the number systems and the solutions of the equation. Didactically systematizing is to construct the model for student's natural mental activity, that is, to construct the stream of experience through which students are considered mathematical concepts as productions from necessities and high probability. For this purpose, we develop the program for the gifted, which its objective is to teach the meanings of the number system and to grasp the algebraic structure conceptually that is guaranteed to solve equations. And we verify the effectiveness of this developed program using didactical experiment. Moreover, the program can be used in ordinary students by replacement the term 'algebraic structure' with the term such as identity, inverse, commutative law, associative law and distributive law, to teach their meaning.

• School Mathematics
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• v.17 no.3
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• pp.377-390
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• 2015

This study attempts to analyse mathematical thinking and attitude of students related to mathematization in the problem solving process and provide implication of teachers' roles. For this, this study analyses mathematical thinking and attitude by dividing the process of solving problems of triangular array into several steps. And it makes a proposal for teachers questioning which can help students according to steps. Therefore this study results students' mathematization needs various steps and compositive mathematical thinking and attitude when students solve even a problem. From the point of view of teachers who attempt to wean students on mathematization, it is necessary for teachers to observe and analyze how students have mathematical thinking and take a stand for mathematics in detail. It also indicates that it is desirable for students who can not move on next step to provide opportunities to learn on their own rather than simply providing students mathematical thinking directly. Students can derive pleasure from the process of solving difficult problems through this opportunity and realize usefulness of mathematics. Finally this experience can build mathematical attitude and prepare the ground to be able to think mathematically.

• Journal of The Korean Association For Science Education
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• v.34 no.4
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• pp.385-391
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• 2014

We use a scale mainly for quantification when we study the psychological characteristics that we cannot observe. The utilization of a scale is frequent in scientific educational studies. The convenience offered by Likert scale, which is among the most frequently used, enable us to grasp characteristic attitude or recognition in students, and evaluate them against an affective domain. But a lot of errors occur, and has been noted as well in the case of utilizing Likert scale in the process. A central tendency in the utilization of Likert scale appears in this study, and the trend analyzes according to study objects and study contents, but we intend to find a way to utilize Likert scale. The results of study made on our countryside students show that the answers tend to get concentrated and a central tendency appears. Our countryside students were aware of the eyes surroundings them, have respect for elders through social experiences, and have had troubles with differentiated expression or personality in the group and cultural environments. According to the object of study, the central tendency appears more among older students than younger students, more among general students than gifted students. In the contents of study, the central tendency has been given more appearance in scope and their exposure has relatively been in large domain. Therefore when utilizing Likert scale in scientific education study, an error of central tendency appears as if they are results of the study. So, when applying the Likert scale to scientific study, we need to consider sociocultural environment, characteristics of an object and contexts of study. This enables avoiding dependence on numerical value of the utilization results, and interpret them correctly.

• Journal of Gastric Cancer
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• v.8 no.4
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• pp.198-203
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• 2008

Purpose: Multiple early gastric cancer (MEGC) accounts for between 4.5% and 11.7% of all early gastric cancers (EGC). We investigated the treatment of MEGC from the viewpoint of the clinicopathologic features of the disease. Materials and Methods: 2,281 patients with EGC underwent gastric resection at the Department of Surgery, Severance Hospital during the 11 years between January 1994 and December 2004 and we carried out a retrospective analysis of these patients. Results: There were 91 cases of synchronous MEGC (4.0%) according to the diagnostic criteria of Moertel: there were 81 double, 9 triple and 1 quadruple lesions. Of the 102 accessory lesions, 64 (62.7%) were less than 10 mm in diameter and 83 (81.4%) were located in the same region as the main lesion. The most frequent histologic type of main lesion was a well differentiated adenocarcinoma, which was found in 52 cases (57.1%). There were 49 mucosal main lesions and 42 submucosal main lesions. Lymph node metastasis was detected in 6 cases (6.6%): 1 in mucosal lesions and 5 in submucosal main lesions Conclusion: Solitary EGC and MEGC had very similar clinopathological features and a similar prognosis. Therefore, we believe that the general EGC treatment guidelines can be applied for multiple EGC. It is important to evaluate the whole stomach before and during the operation and then after examining the resected specimen.

• Journal of the Korean Chemical Society
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• v.63 no.4
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• pp.289-306
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• 2019

The purpose of this study is to compare the contents of chemistry textbooks developed according to the 2015 revised curriculum with the contents of the 2009 revised curriculum to research the change in "the development and use of models". To do this, we analyzed 8 kinds of Chemistry I textbooks and 6 kinds of Chemistry II textbooks from the 2015 revised curriculum and compared them with 4 kinds of Chemistry I textbooks and 4 kinds of Chemistry II textbooks from the 2009 revised curriculum. The scope of the analysis was the explanations of the textbooks related to aqueous electrolysis experiments. In order to compare the contents regarding electrolytes when the same experiments are interpreted with different models, we analyzed contents of 4 kinds of middle school science textbooks from the 2015 revised curriculum and 9 kinds of middle school science textbooks from the 2009 revised curriculum. As a result of the analysis, the same experiment was explained by different models according to the grade level and unit, and all explanations were limited to a single model. Also, the tendency to limit the kinds of electrolytes for controlled experimental results is more pronounced in the 2015 revised curriculum than in the 2009 revised curriculum. From this results, we suggest that efforts are needed to reflect the "development and use of models" in chemistry textbooks developed according to the 2015 revised curriculum.

• Journal of Life Science
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• v.28 no.12
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• pp.1397-1405
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• 2018

Mitochondria have multiple functions in cells: providing chemical energy, storing cellular $Ca^{2+}$, generating reactive oxygen species, and regulating apoptosis. Through these functions, mitochondria are also involved in the maintenance, proliferation, and differentiation of stem/progenitor cells. In the brain, the subventricular zone (SVZ) is one of the neurogenic regions that contains neural stem cells (NSCs) throughout a lifetime. However, reports on the role of mitochondria in SVZ NSCs are scarce. Here, we show that rotenone, a complex I inhibitor of mitochondria, inhibits the proliferation and differentiation of SVZ NSCs in different ways. In proliferating NSCs, rotenone decreases mitosis as measured through phosphorylated histone H3 detection; moreover, apoptosis is not induced by rotenone at 50 nM. In differentiating NSCs, rotenone blocks neurogenesis and oligodendrogenesis while glial fibrillary acidic protein-positive astrocytes are not affected. Interestingly, in this study there were more cells in the differentiating NSCs treated with rotenone for 4-6 days than in the vehicle control group which was a different effect from the reduced number of cells in the proliferating NSCs. We examined both apoptosis and mitosis and found that rotenone decreased apoptosis as detected by staining cleaved caspase-3 but did not affect mitosis. Our results suggest that functional mitochondria are necessary in both the proliferation and differentiation of SVZ NSCs. Furthermore, mitochondria might be involved in the mitosis and apoptosis that occur during those processes.