• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.464-469
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• 1997

The radiopacity of glass ionomer cements is quite variable. The use of a poorly radiopaque material as a base under other restorative materials can mislead the dentist to a diagnosis of recurrent decay. This study investigates the radiopacity of these materials and proposes a minimal radiopacity under which a material should not be used as a base or liner. It is important to determine the radiopacity of glass ionomer dental materials so that the clinician can appreciate the type of restorative materials used when radiographically evaluation the possibility of recurrent dental caries. In this study, radiopacity of Vitrement and Chemfil was compared with that of Cavalite, Miracle mix and polycarboxylate cement. Tooth model of artificial cavity preparation for diagnosis of recurrent caries was omitted. Radiopacity of each material was measured using relatives between thickness and radiopacity of Aluminium step wedge. The results were as follows : 1. Radiopacity of Vitrement was some higher than enamel. 2. Chemfil, restorative glass ionomer, was less radiopaque than enamel. 3. In order of higher radiopacity than enamel, Miracle mix was highest and was followed by polycarboxylate cement, Cavalite and Vitremer. 4. Vitremer, the Glass Ionomer Cement, is useful to detection of recurrent caries, because it is slightly higher radiopaque than enamel. So, it is suitable for restorative material and luting cement.

• Journal of Nutrition and Health
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• v.43 no.2
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• pp.161-170
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• 2010

We surveyed 837 students attending elementary schoolchildren in Korea for health functional foods (HFF) consumption and significant variables for their HFF consumption including demographic characteristics, parental health concern on offsprings, food eating frequency of subjects and beliefs on potential efficacy of HFF by subjects. The consumption prevalence of HFF was 45.9%, and among all types of HFF, nutritional supplements were taken most frequently, followed by apricot extract-fermented products > lactic acid bacteria containing products > EPA/DHA containing products > red ginseng products. HFF consumption was higher in subjects had parents of high education level (p < .05) and those from families with a high socioeconomic status (p < .01) in comparison to each corresponding group. Health concern on offsprings by parents (p < .001) and consumption ratio of HFF by family (p < .001) was higher in consumers than in nonconsumers of HFF. Total score of dietary assessment was higher in consumers than in nonconsumers of HFF (p < .01), and consumers had a more positive view concerning the potential efficacy of HFF than did nonconsumers (p < .001). Most consumers of HFF took HFF when they were healthy (42.5%), and they did not feel special effects through HFF consumption (47.7%). Most consumers of HFF got the information on HFF from family and relatives (24.8%), and most of them purchased HFF at pharmacy or oriental medicine clinics (53.9%). HFF consumers preferred multi-vitamins and Ca-supplements most among the vitamin mineral supplements belonged to HFF. Given the widespread consumption of HFF by elementary schoolchildren, the reasonable consumption of these products for the contribution to their overall health and well-being should be emphasized through nutrition education for them and their family.

• Journal of Nutrition and Health
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• v.46 no.6
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• pp.552-559
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• 2013

This study is conducted in order to investigate the prevalence of vitamin mineral (VM) supplement use and its related factors among Korean adolescents. Using a cross-sectional study design, information was obtained by questionnaires from adolescents selected by stratified sampling in large, small and middle-size cities, as well as rural areas of the whole country, followed by convenience sampling. The total number of participants in this study was 1,407 adolescents ($15.2{\pm}1.6$ years) attending middle or high schools, chosen from various cities and rural areas in Korea. The prevalence of VM supplement use was 65.5%, and there was no significant difference between the genders. City dwellers took VM supplements more frequently than those adolescents from rural areas (p < 0.01). The VM supplement users tended to have higher family income, parents' academic background, and socioeconomic status, respectively (p < 0.001). The greater part of VM supplement users replied that they acquired their nutritional information from their parents, relatives and friends, while many nonusers replied that they did it from school classes (p < 0.05). Compared to nonusers, VM supplement users had greater 'self concern about health' (p < 0.05), 'parents' concern about child's health, growth, and nutritional intake' (p < 0.001), and 'parents' concern about child's grade point' (p < 0.01). However, there was no significant difference between users and nonusers when it came to 'self perception of body shape' or 'BMI'. In addition, users significantly had greater nutritional beliefs concerning VM supplements than nonusers (p < 0.001). These results showed that VM supplement use has been common among adolescents in Korea, and supplement use of subjects has been related with various factors. Among them, it was shown that especially parents great influence the use of VM supplements by adolescents. Thus, not only education for adolescents, but also that for parents is needed to help adolescents take VM supplements properly.

• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.257-262
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• 2008

Genetic diversity of cultivated wheat is narrowing down and is increasingly becoming non-complacent in tackling new pathogenic races and adverse environmental situations. Wild relatives of wheat are rich repositories of beneficial genes that are capable of defying adverse situations. However, these wild species are not readily crossable with cultivated ones. The present study attempted to cross three wild wheat species as females with three cultivated species of varying ploidy to understand the intricate behaviour of hybrids in relation to cytology, morphology, and molecular recombination. Post-fertilization barriers caused hybrid recovery in wild species in contrast to cultivated species. Triticum monococcum did not produce hybrids in any of the crosses. Various degrees of chromosome anomalies and hybrid sterility were seen with hybrids of T. timopheevi and T. sphaerococcum. Cytoplasmic factors were suspected to add more to the abnormality. G genome from T. timopheevi could enhance more pairing between Band D of cultivated species. Precocity of certain chromosomes in laggard formation was evident, pointing towards evolutionary self balance of the genomes which prevented homeologous pairing. They are eliminated in hybrids. Molecular diversity clearly corroborated with genetic proximity of the species, which distinguished themselves by maintaining the genome homeology.

• Journal of the Korean Society of Food Culture
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• v.26 no.2
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• pp.120-127
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• 2011

To identify "Gongsik", defined as food-sharing by picking food from a common plate using personal utensils, we conducted 7 focus group interviews including 47 university students during a 6 month period. Focus group discussions were audio taped, transcribed, and categorized into major themes. We divided Gongsik into the following categories: practical reasons, socio-psychological reasons, boundaries, suppressive situations, emotional characteristics, attitudes towards using different utensils, and future prospects. Gongsik appeared to be useful for fostering quick food sharing, intimacy and solidarity, and a fixed behavior learned at home. If the amount of food was too small to provide individual servings, as in Jjigae, Gongsik was likely to occur spontaneously. Family, close relatives, friends, and lovers sharing common activities and/ or blood ties were composed the boundaries of Gongsik. However, Gongsik was avoided in elegant restaurants or in view of foreigners. Participants showed mixed feelings towards Gongsik. Gongsik conducted with a spoon was considered to increase the degree of suggested intimacy in a food sharing context. Half of the students believed that the practice of Gongsik would be maintained into the future. Gongsik is a culturally-specific behavior that includes both positive and negative meanings. Aside from improving understanding of the cultural aspects of food-sharing, we suggest that the negative aspects of Gongsik related to the issue of hygiene be considered in food and nutrition education.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.43 no.4
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• pp.355-361
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• 2007

A giant jellyfish (Nemopilema nomurai), which is presumed developing in the East China Sea, is recently one of major issues in the Northeast Asia region due to its fatal damage to the fishery. The biomass estimates have generally been conducted by trawl sampling and sighting survey methods. The biological research is also needed to clarify such environmental origin or diurnal migration patterns. While trawl sampling or sighting survey methods are effective to investigate its density estimates in its distributed community of near bottom or surface, they have a problem in investigation on the vertical distribution of jellyfishes. In this case, an echo sounding detection would have an advantage to survey it more extensively and effectively. This trial was conducted to observe the vertical distribution of giant jellyfish, where thermocline strongly formed, during mooring at each station of the East China Sea and southern coastal area using acoustical and optical methods. By the results, they were observed to exit and move at the water column under the thermocline using the optical camera and echo sounder system, and the information was analyzed to find out the acoustical sound scattering characteristics relatives to 120kHz frequency. These results can be utilized effectively to estimate the vertical distribution and biomass of Giant jellyfish with comparing results from trawl sampling and sighting survey methods, hereafter.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.299-307
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• 2012

In this study, Kimchi usage was examined by nationwide consumers. 1,000 consumers between 20~60 years olds from 15 cities/province based on an administrative district participated in this questionnaire, which were one-on one interviews from September 23th to October 14th, 2009. 76.1% of the customers prepared Kimchi by them self, 26.9% customers received Kimchi from relatives and, 13.1% purchase Kimchi from the market. In addition, the rate of preparing Kimchi by themselves increased with age(p<0.05). 4~6 cabbage heads(34.5%) was the most preferred quantity for preparing Kimchi at a time, which was followed by more than 10 heads(25.2%) and 2~3 heads(22.9%). Chinese cabbage Kimchi was the most preferred type for purchase. 49.1% of customers purchased Kimchi at the supermarket and warehouse market and the origin of the ingredients, taste and-, price of Kimchi were considered important factors. The satisfactory scores of selling Kimchi were variety 3.60, taste 3.11, freshness of main ingredient 3.10, hygiene 2.86, -appropriate salt usage 2.99 and-, the origin of ingredients 2.94. There were significant difference between gender in taste and hygiene of selling Kimchi (p<0.05). In conclusion, to provide more appropriate Kimchi based on changes in Kimchi usage and consumption patterns at home and in the community, new types of Kimchi should be developed.

• Journal of Family Resource Management and Policy Review
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• v.12 no.1
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• pp.21-39
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• 2008

The purpose of this study was to investigate service support programs for the work-family balance in the community. Service support programs in the community are at beginning stages of development, because it has taken about 10 years to put a self-governing system into practice in Korea. This study concentrates on service support programs developed by various service organizations in the city and does not include any rural districts. First, the developmental process of the work-family balance model and type of the service support program in the community were studied. Next, the situation of care service support was examined based on written articles. Finally, a few suggestions were made f3r work-family balance in the community. The developmental situation of work-flmily balance in Korea is in a stage which is shifting from the company-leading model to a family-company-community model. The most common type of service support program offered in the community until now has been the informal sector through relatives, neighbors or friends. However, service support programs, in the public sector by the government and in the voluntary sector by nonprofit organizations and corporations, has rapidly been growing and the number of services from each sector has also increased. Profit organizations in the private sector, such as medical and care service centers, are also now rapidly increasing. It appears that service support programs contributing to the work-family balance in the community come from a number of sectors, including public, voluntary, private and informal sectors, to suit consumer needs.

• Korean Journal of Plant Taxonomy
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• v.34 no.2
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• pp.75-85
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• 2004

Here we described and illustrated two new taxa of Allium (Alliaceae) from southern part of Korea. One new species, A koreanum H. J. Choi et B. U. Oh was clearly distinguished from A. splendens of sect. Reticulato-bulbosa by larger and stellately spreading pale pink perianth, apparently exsert filaments, and conical stigma as well as chromosome number. Another new variety, A. thunbergii var. teretifolium H.J. Choi et B.U. Oh was also easily distinguished from its relatives, var. thunbergii and var. deltoides by terete and hollow leaf blade. Keys to the two species of Allium sect. Reticulato-bulbosa and the three varieties of A. thunbergii (sect. Sacculiferum) in Korea were described.

• Animal cells and systems
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• v.5 no.3
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• pp.163-177
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• 2001

Most, if not all, aphids harbor intracellular bacterial symbionts, called Buchnera, in their bacteriocytes, huge cells differentiated for this purpose. The association between Buchnera and aphids is so intimate, mutualistic and obligate that neither of them can any longer reproduce independently. Buchnera are vertically transmitted through generations of the host insects. Evidence suggests that Buchnera were acquired by a common ancestor of aphids 160-280 million years ago, and have been diversified, since then, in parallel with their aphid hosts. Molecular phylogenetic analyses indicate that Buchnera belong to the g subdivision of the Proteobacteria. Although Buchnera are close relatives of Escherichia coli, they contain move than 100 genomic copies per cell, and their genome size is only one seventh that of E. coli. The complete genome sequence of Buchnera revealed that their gene repertoire is quite different from those of parasitic bacteria such as Mycoplasma, Rickettsia and Chlamydia, though their genome sizes have been reduced to a similar extent. Whereas these parasitic bacteria have lost most genes for the biosynthesis of amino acids, Buchnera retain many of them. In particular, Buchnera's gene repertoire is characteristic in the richness of the genes for the biosynthesis of essential amino acids that the eukaryotic hosts are not able to synthesize, reflecting a nutritional role played by these symbionts. Buchnera, when housed in the bacteriocyte, selectively synthesize a large amount of symbionin, which is a homolog of GroEL, the major stress protein of E. coli. Symbionin not only functions as molecular chaperone, like GroEL, but also has evolutionarily acquired the phosphotransferase activity through amino acid substitutions. Aphids usually profit from Buchnera's fuction as a nutritional supplier and, when faced with an emergency, consume the biomass of Buchnera cells as nutrient reserves.