• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.3
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• pp.198-204
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• 1988

This study was aimed at obtaining elementary data on enzymatic browning of potato and potato products and examining the inhibitory method of browning. Therefore, we extracted polyphenol oxidase from potatoes(Solanum tubersum L.), and investigates its general properties and inhibiting effects of its activity with the different concentrations of sulfites($Na_2S_2O_4,\;Na_2SO_3{\cdot}7H_2O,\;NaHSO_3$). The optimum pH and temperature of polyphenol oxidase were observed to be 6.5 and $37^{\circ}C$ respectively. The polyphenol oxidase at PH5 was very stable, and the activity of polyphenol oxidase between pH $5.0{\sim}9.0$ was estimated to be relatively high, showing $72{\sim}75%$ of its activity at pH5. The polyphenol oxidase was very stable when heated at $40^{\circ}C$ for one hour, and almost 50% of enzyme activity was decreased when heated at $70^{\circ}C$ for twelve minutes. At 0.1mM concentrating of sulfites the relative activity of polyphenol oxidase was 98% in all the three cases of sulfites. Thus sulfites at 0.1mM concentration was found to have little inhibiting effect on polyphenol oxidase activity. At 1mM concentration of sulfites $NaHSO_3$ showed the lowest 36% relative activity among the three. At 5mM concentration of sulfites, the relative activity of $Na_2SO_3{\cdot}7H_2O$ was the lowest 14%.

• Korean Journal of Ichthyology
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• v.12 no.2
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• pp.129-136
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• 2000

The aucha perch, Coreoperca kawamebari was collected in Tam-jin river from February to June 1998. It was reared in the laboratory and observed the spawning behavior and early life history. Spawning season was from mid of April to the end of May in the Tam-jin river. The fertilized eggs were demersal of adhesive, transparent and spherical in shape. Egg diameter was 2.21~2.65 mm with several oil globule of 0.058~0.343 mm. Hatching occurred about 194 hours 23 minutes after fertilization at water temperature of $18{\sim}22^{\circ}C$. Newly-hatched larvae were 5.09~5.68 mm in total length(TL, mean: 5.38mm) with 10~11+18=28~29 myotomes and opened mouth and anus. Melanophores were distributed on the eye lens, on the head, around the yolk, on the dorsal part and the abdominal region of the trunk. After hatching 5 days larvae attained 6.12~6.68 mm in TL (mean: 6.47 mm), and the yolk sac was completely absorbed and transformed to postlarva stage. The larvae reached to the juvenile stage with all the fins were formed with complete set of fin rays (D. XII-12~13; A. III-8~10; P. 11~13; V. I-4~5) at the 22 days after hatching and of the larvae was 11.54 mm in total length. In 32 days after hatching, the juvenile was 13.05 mm in TL. This period was similar to adult in body form and the spot.

• Journal of The Korean Association For Science Education
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• v.38 no.6
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• pp.765-780
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• 2018

The purpose of this study is to synthesize the theoretical perspectives, research methods, and research results of teachers' professional vision by reviewing and analyzing previous research papers and to suggest implications for science teacher education and research. Three databases were used to search peer reviewed journal articles published between 1997-2017, which include 'teachers' and 'professional vision' explicitly in abstracts and empirical studies only. 21 articles in total were analyzed and review results are as follows. First, researchers regarded professional vision as a new concept of teacher professionalism. Previous research viewed professional vision as integrated structure of teachers' knowledge or ability activated at specific moment. Second, the analytical framework of professional vision included two aspects; 'selective attention' and 'reasoning'. Several aspects of lessons or the desirable teaching and learning factors are suggested as the subcategories of selective attention. Hierarchical levels or independent reasoning ability factors are suggested as the subcategories of reasoning process. Third, research on teachers' professional vision focused more on middle school teachers than elementary teachers and on various subject areas. Most studies used video clips and more cases of using videos of non-participants were found. In case of measurement of professional vision, most quantitative scoring methods were whether the responses of experts and teachers on video clips were consistent. Last, most studies examined or assessed teachers' professional vision. It is reported that in-service teachers' professional vision was evaluated higher than novice teachers' and using video clips were effective to examine and improve teachers' professional vision.

• Journal of Nutrition and Health
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• v.55 no.1
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• pp.21-35
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• 2022

The recommended meal composition allows the general people to organize meals using the number of intakes of foods from each of six food groups (grains, meat·fish·eggs·beans, vegetables, fruits, milk·dairy products and oils·sugars) to meet Dietary Reference Intakes for Koreans (KDRIs) without calculating complex nutritional values. Through an integrated analysis of data from the 6th to 7th Korean National Health and Nutrition Examination Surveys (2013-2018), representative foods for each food group were selected, and the amounts of representative foods per person were derived based on energy. Based on the EER by age and gender from the KDRIs, a total of 12 kinds of diets were suggested by differentiating meal compositions by age (aged 1-2, 3-5, 6-11, 12-18, 19-64, 65-74 and ≥ 75 years) and gender. The 2020 Food Balance Wheel included the 6th food group of oils and sugars to raise public awareness and avoid confusion in the practical utilization of the model by industries or individuals in reducing the consistent increasing intakes of oils and sugars. To promote the everyday use of the Food Balance Wheel and recommended meal compositions among the general public, the poster of the Food Balance Wheel was created in five languages (Korean, English, Japanese, Vietnamese and Chinese) along with card news. A survey was conducted to provide a basis for categorizing nutritional problems by life cycles and developing customized web-based messages to the public. Based on survey results two types of card news were produced for the general public and youth. Additionally, the educational program was developed through a series of processes, such as prioritization of educational topics, setting educational goals for each stage, creation of a detailed educational system chart and teaching-learning plans for the development of educational materials and media.

• Journal of dental hygiene science
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• v.6 no.3
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• pp.207-212
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• 2006

In parallel with social and economic progress, motives of patients to consult dentists have increased and diversified. An increasing number of people visit dental clinics to improve their facial appearance and masticating functions deteriorated largely due to malocclusion. There is also greater interest in and concern as well as demand for teeth alignment treatment among people. Under this situation, it is required to find and suggest ways to enhance quality and profitability of dental care in view of managerial needs for dentists to cope with changing circumstances. This study, thus, aims to measure satisfactions of orthodontics patients and to determine the elements influencing their satisfactions. For this aim, a survey was performed for 20 days from March 7th to 26th, 2005 by means of questionnaires distributed to randomly selected samples, resulting in following conclusions: 1. From comparison of satisfactions with dental service by their elements, higher satisfaction was reported from orthodontics patients in the element of dental hygienists(4.21). Least satisfaction, however, was found in the procedure for treatment and waiting hours(3.73). 2. By gender, male orthodontics patients turned out to be more satisfactory with dental service than females. In terms of intention for return visits, both male and female orthodontics patients showed higher satisfaction than non-orthodontics ones. 3. As for satisfaction with dental service by age of orthodontics and non-orthodontics patients, with regard to intention for return visit, orthodontics patients of all ages showed to have higher grade of satisfaction. 4. Regarding satisfaction with dental treatment by orthodontics and non-orthodontics patients by monthly income, Dental hygienist with intention for return visit, the higher the satisfaction of orthodontics patients. 5. In regard to satisfaction with dental treatment by education, higher satisfaction was expressed by orthodontics patients with elementary school education kept dentist, dental hygienist and internal and external environments. As a result from this study, we knew that dental service of the orthodontics patients is higher satisfaction than that of the non-orthodontics patients.

• Journal of Nutrition and Health
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• v.53 no.5
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• pp.503-517
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• 2020

Purpose: This study examined the yearly trend of milk consumption and the nutritional status of subjects aged 6-18 years using the 2007-2015 Korea National Health and Nutrition Examination Survey data. Methods: Milk and dairy products were classified into plain milk, flavored milk, and dairy products (ice cream, milkshakes, cheese, and yogurt, etc.). This study compared the milk and dairy products intakes, some nutrients intakes and percent of dietary reference intakes for Koreans in the milk intake and non-milk intake groups. Results: Plain milk intake decreased with year (male, p = 0.0199; female, p < 0.0001; elementary school, p = 0.0013; high school, p = 0.0061), whereas flavored milk and dairy products intake in these subjects increased with year. In all subjects, 49.9% of subjects did not drink milk at all. The intakes of energy, protein, fat, calcium, phosphorus, and riboflavin in the milk intake group were significantly higher than those in the non-milk intake group, even after adjusting for covariates (p < 0.05). The odds ratio of the prevalence of nutritional deficiency in the non-milk intake group was 3.2 times higher than that of the milk intake group (p < 0.001), even after adjusting for covariates. The odds ratio for the prevalence of excess intake of the energy/fat was not significant with milk intake. Conclusion: The prevalence of milk intake decreased every year in the subjects. Calcium deficiency and nutritional deficiency were very high in the non-milk intake group. Efforts should be made to improve the calcium status in children and adolescents by strengthening nutrition education about the importance of milk intake.

• Journal of Nutrition and Health
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• v.49 no.1
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• pp.36-42
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• 2016

Purpose: This study was conducted for comparison of salty taste assessment, salty taste preference, high-salt dietary attitude, and high-salt dietary behavior by stages of behavior change among school-aged children and adolescents. Methods: A total of 1,595 students (1,126 school- aged children, 469 adolescents) from 43 elementary schools and 17 middle and high schools in Daegu were tested using salty taste kits and surveyed using questionnaires on stages of behavior change, high-salt dietary attitude, and behavior. Results: Adolescents showed a significantly higher result for salty taste assessment than school-aged children (p < 0.01). In salty taste assessment, the students of pre-contemplation stage (n = 498) and contemplation stage (n = 686) showed higher scores than students of action stage (n = 351) and maintenance stage (n = 60). Regarding the salty taste preference, students of maintenance stage preferred the lower two samples (0.08%, 0.16%) and students of pre-contemplation stage preferred the higher two samples (0.63%, 1.25%). High-salt dietary attitude scores and dietary behavior scores were highest for students of pre-contemplation stage and were lowest for students of maintenance stage. Conclusion: Salty taste assessment, high-salt dietary attitude, and high-salt dietary behavior were significantly different by stages of behavior change among school-aged children and adolescents. This study suggests the need for examination of the stages of behavior change before nutrition education for effective education.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.132-139
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• 2017

The purpose of this study was to obtain data for contribution of job characteristics (workload, autonomy, reward, community, fairness, and value) to job burnout (emotional exhaustion, and cynicism), and job engagement (vigor, dedication, and absorption) in foodservice dietitians. Our survey was administered to 393 school foodservice dietitians in the Busan area on February 11, 2014. The mean scores of nutrition teachers were significantly higher for autonomy (P<0.01), reward (P<0.05), community (P<0.01), fairness (P<0.001), and value (P<0.001) than unlimited period contract dietitians. The mean scores of high school dietitians were significantly higher for emotional exhaustion (P<0.01) and cynicism (P<0.001) than elementary school dietitians and middle school dietitians. Workload (r=-0.609, P<0.001), reward (r=-0.417, P<0.001), and fairness (r=-0.394, P<0.01) correlated significantly with emotional exhaustion. Reward (r=-0.324) and value (r=-0.423) correlated significantly (P<0.01) with cynicism. Value correlated significantly (P<0.01) with vigor (r=0.493), dedication (r=0.480), and absorption (r=0.460). Workload (${\beta}=-0.521$, P<0.001) had the highest negative influence on emotional exhaustion, whereas value (${\beta}=-0.325$, P<0.001) had the highest negative influence on cynicism. Value had the highest positive influence on vigor (${\beta}=0.392$, P<0.001), dedication (${\beta}=0.443$, P<0.001), and absorption (${\beta}=0.444$, P<0.001). Based on the results of this study, school management should plan job characteristics strategies to reduce workload and increase value for school foodservice dietitians.

• Journal of the Korean earth science society
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• v.33 no.4
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• pp.360-375
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• 2012

The purpose of this study was to compare 10th grade students' understanding of concepts about the plates' motions depending on the different spatial ability. Based on previous studies and literature reviews, two instruments were selected and used in this study. The Spatial Perception Test developed in Korean Testing Center was applied to measure students' spatial ability. Another instrument for testing students' understandings of plates' motions consists of a total of 10 items. The instruments were distributed to 118 students who were 10th graders in metropolitan city. The results are as follows: First, a correlation coefficient between conceptual understanding of plates' motions and spatial ability was r=0.439 (p<.01). It indicates that conceptual plates' motions and spatial ability have a moderate relationship. The students were divided into two groups (high and low) by spatial ability. The independent t-test was performed and reveals that the statistically significant difference between high and low groups. On the other hand, the 6 students (3 higher spatial ability students and 3 lowers) were selected and interviewed individually to find the differences in their understanding of the concept of plates' motions. The findings from interviews indicate that most students recognized about concepts of trench and ocean ridge, a rise and drop of the mantle, and divergent and convergent boundaries. However, students had misconceptions about section of trench and ocean ridge. In addition, the students who had higher spatial ability knew the more proper concepts about the creation and extinction of plate, crustal movements, and bottom of the ocean extension, whereas the students who had the lower spatial ability had misconceptions.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.2
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• pp.291-297
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• 2003

While making diagnosis and the treatment plan for the growing children who visited at Chonnam National University Hospital for orthodontic treatment, authors obtained 8 lateral cephalometric measurements in antero-posterior and vertical relationship such as APDI, WITS, ANB, SN-MP, ODI, PFH/AFH, Y-axis, SUM for children aged 7 to 9 with class III malocclusion and compared them with these of 73 children of elementary school aged 7 to 9 with proper profile and normal occlusion in Gwangju. The results were as follows: 1. Between normal occlusion and class III malocclusion, ANB, SN-MP, ODI, SUM, except PFH/AFH and Y-axis showed statistically significant differences(p<0.05). 2. Between mesurements to describe skeletal disorder of antero-posterior relationship such as APDI, WITS, ANB and skeletal disorder of vertical relationship such as SN-MP, ODI, PFH/AFH, Y-axis, SUM, all of them in both normal occlusion and Class III malocclusion showed significant correlation, except Y-axis, SUM correlation(p<0.01). 3. Wald' statistics of WITS, ANB and APDI expressing skeletal disorder of antero-posterior relationship showed 7.118, 5.148, 0.741, respectively and Wald' statistics of ODI, Y-axis, PFH/AFH, SN-MP, SUM were presented 28.348, 2.238, 1.376, 0.090, 0.089, respectively. Therefore, WITS and ODI could be considered as useful diagnotic measurements for class III malocclusion.