• Journal of Korean Elementary Science Education
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• v.24 no.3
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• pp.259-267
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• 2005

This study was to investigate the elementary students' preconception on the brightness of electric bulb and degree of consistency on their preconceptions. Participants were 160 students of fifth graders in Seoul area. They had already teamed about the brightness of series circuit and parallel circuit of batteries. After they solved six problems in the same context, we provided them a pair of circuit which was an anomalous situation. And then they conducted CCLT (Cognitive Conflict Level Test). Elementary school students showed various preconceptions when they explained the light of bulb of two Simple electric Circuits. Many Students Consistently Showed the Scientific misconceptions like 'the light of bulb of two simple electric circuits was that the more batteries and the fewer bulbs were brighter.' The level of consistency that students presented scientific misconceptions was grouped all of four, such as 'high, middle, low, and nothing.' Therefore the higher scientific achievement they have, the higher consistency they have. As the students had high consistency level, they revealed high cognitive conflict level significantly. This high consistency will help them to change their preconception on the brightness of electric bulb and their cognitive conflict.

• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.47-57
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• 2015

Sodium is an essential nutrient with very important functions, including regulation of the extracellular fluid volume and active transport of molecules across the cell membranes. Since high levels of dietary sodium are associated with a high prevalence of hypertension, prehypertension, and other adverse effects on health, many national and international health organizations (WHO, FAO, etc.) recommend that sodium intake should be significantly decreased. In developed nations, cheese products, from among many processed foods, can cause high salt intake. Hence, there is an urgent need to reduce the content of salt in cheese processing, using various substitutes of sodium chloride (NaCl). In general, salt (NaCl) has been used as a food preservative to limit and (or) kill the growth of foodborne pathogens and spoilage organisms by decreasing the water activity, and to improve texture and flavor. To maintain public health, the salt content in cheese should be decreased without influencing the physicochemical properties of cheese. Therefore, the objective of this review is to outline the upcoming technologies used to reduce the salt content in different types of cheese using various substitutes.

• Journal of Plant Biotechnology
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• v.41 no.3
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• pp.146-158
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• 2014

Camelina sativa that belongs to Brassicaceae family is an emerging oilseed crop. Camelina seeds contain approximately 40% storage oils per seed dry weight, which are useful for human and animal diets and industrial applications. Microsomal delta-12 fatty acid desaturase2 (FAD2) catalyzes the conversion of oleic acid to linoleic acid. The polymorphisms of FAD2 genes are correlated with the levels of oleic acids in seed oils. Microsomal delta-12 fatty acid desaturase2 (FAD2) catalyzes the conversion of oleic acid to linoleic acid. The polymorphisms of FAD2 genes are correlated with the levels of oleic acids in seed oils. In this study, three CsFAD2 genes (CsFAD2-1, CsFAD2-2 and CsFAD2-3.1) were isolated from developing seeds of Camelina sativa (L.) cv. CAME. The nucleotide and deduced amino acid sequences of three CsFAD2 genes were compared with those from dicotyledon and monocotyledon plants including Camelina cultivars Sunesone and SRS933. Three histidine motifs (HECGH, HRRHH, and HVAHH) required for FAD activity and a hydrophobic valine or isoleucine residue, which is a SNP (single nucleotide polymorphism) marker related with enzyme activity are well conserved in three CsFAD2s. The expressions of CsFAD2-1 and CsFAD2-3.1 were ubiquitously detected in various Camelina organs, whereas the CsFAD2-2 transcripts were predominantly detected in flowers and developing seeds. The contents of oleic acids decreased, whereas the amounts of linoleic acid increased in dry seeds of transgenic fad2-2 lines expressing each CsFAD2 gene compared with fad2-2 mutant, indicating that three CsFAD2 genes are functionally active. The isolated CsFAD2 genes might be applicable in metabolic engineering of storage oils with high oleic acids in oilseed crops.

• Journal of Korea Soil Environment Society
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• v.1 no.1
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• pp.47-54
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• 1996

Soil pollution indices (SPI) were designed for estimating quality of soil polluted with arsenic and heavy metals. Applying the quality reference value of soil based on its multifunctional purpose was a key step. For considereing multifunctions of soil, soil was classified into 4 groups-agricultural land, residential area, recreational area, factorial site. Then, each concentration of arsenic and each of five heavy metals (Cd, Cu, Hg, Pb, Zn) in soils grouped was transformed to a mathematical value based on the soil quality reference value which may stand for ecological impact. Soil pollution score (SPS) was the addition of the 6 values transformed, and the range of the SPS was divided into 4 Soil Pollution Classes (SPC). The SPC 1, 2, 3, and 4 were SPS <100, SPS 100-200, SPS >200-300, and SPS >300, repectively. SPS and SPC were evaluated with the results of the data from employing the Soil Network of 1994. Based on the soil quality reference values, SPS and SPC of the Soil Network's data were transformed and classified, respectively. Then, SPS and SPC were compared with arsenic and the 5 heavy metal contents of their reference values resulted from the Soil Network's. From this method, soil quality of most of the Soil Network area was estimated to be healthy. However, ca. 3.0~4.0% of the Soil Network area was determined in a range of slightly and heavily polluted. As the mean value of SPS of the Soil Network's was 66.2 which indicates most of soil evaluated was healthy. When the SPSs of the data were divided into 4 groups of SPC, Class 1 (Good quality of soil), Class 2 (Need to be checked area 1), Class 3 (Need to be checked area 2) and Class 4 (Polluted area) were 87.0, 9.4, 2.4, 1.2%, respectively. Using SPI were comparable to those of heavy metal contents in soils, and would be comprehenve to determine the status of soil qulity. Methodology of the developing SPI would be applicable to the other soil pollutants such as organic and inorganics than arsenic and 5 heavy metals used here.

• 대한공업교육학회지
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• v.33 no.2
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• pp.192-217
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• 2008

This paper investigated the perceived criticalities and patterns of Korean Professional Engineer's competency regarding the working activities of automative product development, manufacturing, etc by using questionnaires responded to the survey which were applied to the automotive professors, experts and professional engineers (vocational parties) by e/mail, etc. This research investigated the following questions: First, what are the characteristic patterns, relevancy and perceived criticalities of Korean Professional Engineer's competencies? Second, What are the ranked priority of the Korean Professional Engineers' competencies? Are there any differency for each item, sub group of job, intelectual criterior of the competencies between relevancy and perceived criticalities according to the types of vocational parties, etc.? Accoring to the results; first, Professor group showed highest points among 3 groups per each item of the competencies by vocational parties Second, Chassis design group ranked top position among the 8 sub groups by vocational parties and, third, Problem Solving Knowledge ranked highest points than any others. Korean Professional Engineers are found to be positioned as key members, leaders and managers on surveying market, product planning, designing product & components, developing component parts, establishing shop with production equipment, managing quality control & material handling, organizing relevant meetings, developing human resources by training and learning, to back up finance with law matters, cooperating with concerned parties to achieve organizational goals, and to coordinate projects. etc, identifying ethical issues and business skills in order to survive and win to be competitive in various kinds of the automotive industry battle fields.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1084-1091
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• 2002

Mortierella alpina, a common soil fungus, is the most efficient organism for production of production acid presently known. Since arachidonic acid are important in human brain and retina development, it was undertaken the growing effect containing diet as a food ingredient. Arachidonic acid rich oil derived from Mortierella alpina, was subjected to a program of studies to establish for use in diet supplement. This study was compared the growth and learning effect of fungal oil rich in arachidonic acid by incorporated into diets ad libitum. Sprague-Dawley rats received experimental diets 5 groups (standard AIN 93 based control with beef tallow, extract oil 8%, and 4%, and Mortierella alpina in diet 10% and 20%) over all experiment duration (pre-mating, mating, gestation, lactation, and after weaning 4 weeks). Pups born during this period consumed same diets after wean for 4 weeks. There was no statistical significance of diet effects in reproductive performance and fertility from birth to weaning. But the groups of Mortierella alpine diet were lower of weight gain and diet intake after weaning. The serum lipids were significantly different with diet groups, higher TG in LO (oil 4%) group of dams, and higher total cholesterol in LF (M. alpina 10%) of pups, although serum albumin content was not significantly different in diet group. The spent-time and memory effect within 4 weeks of T-Morris water maze pass test in dam and 7-week- age pups did not differ in diet groups. On the count of backing error in weaning period of pups was lower in HO(extracted oil 8%) group. In the group of 10% and 20% Mortierella alpina diet, DNA content was lower in brain with lower body weight, but liver DNA relative to body weight was higher than control. Further correlation analyses would be needed DNA and arachidonic acid intakes, with Mortierella alpina diet digestion rate.

• The Journal of the Korea Contents Association
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• v.6 no.12
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• pp.253-260
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• 2006

As media and product became variety, the propensity of the people is be coming various. From diversity, there we could search for some popularity is called 'the mania.' When Mania takes shape, the product will being longer even masses in these days only have short-term life. Also there are hundreds of animations that has short-term life whom people forgot everyday they watch. However, the animations could lasting its value which has the Mania. This thesis is a studies on the constitution of Mania from animation 'Fullmetal Alchemist's Character The BONES had made. We can learn that the audience were not just like the animation, but get crazy for it by comparing Japanese animation industry in those days; before it has been shrinking and manufacturing various contents from Fullmetal Alchemist means there is enough consumtions. There are many reasons to form Mania group, but specially the character symbols at the works as a whole. From this study is to know a cause of how the animation 'Fullmetal Alchemist' made huge Mania group, and significance value of the work those group left.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1229-1235
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• 1998

To see the correlation between the rate of in vitro starch hydrolysis and the glycemic index, an in vitro digestion was carried out by incubating the cereal samples for 2 hours with ${\alpha}-amylase$ in dialysis tubing. Also the levels of blood glucose were measured over 2 hours after feeding healthy volunteers with 50 g carbohydrate portions. Hydrolysis area, hydrolysis index (HI) and the dialysate content of carbohydrate throughout the digestion time for barley was significantly below those for other cereals (p<0.05), and unpolished glutinous rice was significantly above (p<0.05). The GI-glucose of barley $(57%{\pm}7)$ to glucose as standard was significantly (p<0.05) lower than those of other cereals whereas the GI-glucose of glutinous rice $(110%{\pm}8)$ was significantly higher (p<0.05) than other cereals. The GI-rice values to rice as standard were $122%{\pm}4$ for glutinous sorghum, $116%{\pm}13$ for job's tear, $115%{\pm}13$ for glutinous millet, $106%{\pm}6$ for unpolished glutinous rice, $102%{\pm}7$ for glutinous rice, $100%{\pm}0$ for rice, $90%{\pm}12$ for unpolished rice, $85%{\pm}6$ for foxtail millet, $79%{\pm}5$ for buckwheat and $63%{\pm}6$ for barley. The GI-rice was significantly correlated to hydrolysis area and HI (r=0.75, p<0.01). It suggests that the in vitro starch hydrolysis offers good potential to predict the in vivo glycemic response of starch foods.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.07b
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• pp.67-88
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• 2003

The consumption of poultry meat (chicken and turkey) grew the most during the past few decades due to several contributing factors such as low price. product research and development. favorable meat characteristics, responsive to consumer needs, vertical integration and industry consolidation, new processing equipments and technology, and aggressive marketing. The major processing technologies developed and used in chicken processing include forming/restructuring, tumbling, curing, smoking, massaging, injection, marination, emulsifying, breading, battering, shredding, dicing, and individual quick freezing. These processing technologies were applied to various parts of chicken including whole carcass. Product developments using breast, thigh, and mechanically separated chicken meat greatly increased the utilization of poultry meat. Chicken breast became the symbol of healthy food, which made chicken meat as the most frequent menu items in restaurants. However, the use of and product development for dark meat, which includes thigh, drum, and chicken wings were rather limited due to comparatively high fat content in dark meat. Majority of chicken are currently sold as further processed ready-to-cook or ready-to-eat forms. Major quality issues in chicken meat include pink color problems in uncured cooked breast, lipid oxidation and off-flavor, tenderness PSE breast, and food safety. Research and development to ensure the safety and quality of raw and cooked chicken meat using new processing technologies will be the major issues in the future as they are now. Especially, the application of irradiation in raw and cooked chicken meat products will be increased dramatically within next 5 years. The market share of ready-to-eat cooked meat products will be increased. More portion controlled finished products, dark meat products, and organic and ethnic products with various packaging approaches will also be introduced.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.278-285
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• 2016

The bifunctional PheA protein, having chorismate mutase and prephenate dehydratase (CMPD) activities, is one of the key regulatory enzymes in the aromatic amino acid biosynthesis in Escherichia coli, and is negatively regulated by an end-product, phenyalanine. Therefore, PheA protein has been thought as useful for protein engineering to utilize mass production of essential amino acid phenylalanine. To obtain feedback resistant PheA protein against phenylalanine, we mutated by using random mutagenesis, extensively screened, and obtained $pheA^{FBR}$ gene encoding a feedback resistant PheA protein. The mutant PheA protein contains substitution of Leu to Phe at the position of 118, displaying that higher affinity (about $290{\mu}M$) for prephenate in comparison with that (about $850{\mu}M$) of wild type PheA protein. Kinetic analysis showed that the saturation curve of $PheA^{FBR}$ against phenyalanine is hyperbolic rather than that of $PheA^{WT}$, which is sigmoidal, indicating that the L118F mutant enzyme has no cooperative effects in prephenate binding in the presence of phenylalanine. In vitro enzymatic assay showed that the mutant protein exhibited increased activity by above 3.5 folds compared to the wild type enzyme. Moreover, L118F mutant protein appeared insensitive to feedback inhibition with keeping 40% of enzymatic activity even in the presence of 10 mM phenylalanine at which the activity of wild type $PheA^{WT}$ was not observed. The substitution of Leu to Phe in CMPD may induce significant conformational change for this enzyme to acquire feedback resistance to end-product of the pathway by modulating kinetic properties.