• Journal of Veterinary Clinics
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• v.28 no.5
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• pp.486-496
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• 2011

A special mesenchymal tissue layer called perichondrium has a chondrogenic capacity and is a candidate tissue for engineering of cartilage. To overcome limited potential for chondrocyte proliferation and re-absorption, we studied a method of cartilage tissue engineering comprising chondrocyte-hydrogel pluronic complex (CPC) and cultured perichondrial cell sheet (cPCs) which entirely cover CPC. For effective cartilage regeneration, cell-sheet engineering technique of high-density culture was used for fabrication of cPCs. Hydrogel pluronic as a biomimetic cell carrier used for stable and maintains the chondrocytes. The human cPCs was cultured as a single layer and entirely covered CPC. The tissue engineered constructs were implanted into the dorsal subcutaneous tissue pocket on nude mice (n = 6). CPC without cPCs were used as a controls (N = 6). Engineered cartilage specimens were harvested at 12 weeks after implantation and evaluated with gross morphology and histological examination. Biological analysis was also performed for glycosaminoglycan (GAG) and type II collagen. Indeed, we performed additional in vivo studies of cartilage regeneration using canine large fullthickness chondrial defect model. The dogs were allocated to the experimental groups as treated chondrocyte sheets with perichondrial cell sheet group (n = 4), and chondrocyte sheets only group (n = 4). The histological and biochemical studies performed 12 weeks later as same manners as nude mouse but additional immunofluorescence study. Grossly, the size of cartilage specimen of cPCs covered group was larger than that of the control. On histological examination, the specimen of cPCs covered group showed typical characteristics of cartilage tissue. The contents of GAG and type II collagen were higher in cPCs covered group than that of the control. These studies demonstrated the potential of such CPC/cPCs constructs to support chondrogenesis in vivo. In conclusion, the method of cartilage tissue engineering using cPCs supposed to be an effective method with higher cartilage tissue gain. We suggest a new method of cartilage tissue engineering using cultured perichondrial cell sheet as a promising strategy for cartilage tissue reconstruction.

• Korean Journal of Human Ecology
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• v.10 no.2
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• pp.77-87
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• 2007

This research investigated the eating out and snack intakes situation of five hundred eighty five $5^{th}\;and\;6^{th}$ graders living in the city and rural parts of Jeonbuk province. The results of this study are as followed: Nuclear families in urban area and rural community are 84.5% and 64.7% respectively. On the other hand, extended families are 7.9% in urban area and 18% in rural communities. Out of all the households, 34.3% (urban: 37.2%, rural community: 31.5%) answered they like to eat out. Over 50.3% preferred eating Korean style food and the reason was 'the taste': urban (71.4%) and rural community (67.8%). People living in urban communities seemed to eat out more frequently than rural places and $3{\sim}4$ times a month was the average. Usually people seemed to eat out during the weekends and in the evening time 84.3% (after 7:00 p.m.). Based on each family's living standard, people answered 'we hardly ever eat out' for those in the lower class (59.1%), the middle class said once or twice a week (47.1%), and the upper class (35.7%). It was obvious that people in the middle and upper class tend to eat out more frequently than those in the lower class. The most common period of time which snacks were taken was after school (38.5%), on the way back from educational institute (35.0%) and the choices of snacks which they purchased were frozen sweets (56.4%)chips & cookies (25.2%) beverages (9.9%) Fast foods (4.6%) and fried foods (3.9%) in order. Urban children seem to eat more frozen sweets and rural children ate more chips & cookies. Also, amount of snacks between meals showed a higher percentage to those who had more pocket money, The type of snacks were fruits (37.1%) chips and cookies et cetera (19.2%) instant foods (12.8%) dairy products (11.1%) confectionary (10.3%) fried foods (5.1%) in order. The result shows that urban children eat out more frequently than those in rural areas, Eating around 7:00 p.m. was most common and the middle and upper class tend to eat out more frequently than those in the lower class, Also, snacks were most often bought before and after school. After 10:00 p.m frozen goods and chips were the most preferred choice. Specially, the reason for eating fast foods was because of the pleasing taste. From this study, it is clear that eating out and having snacks became pervasive into our lives in both urban and rural areas. Hereafter, an appropriate eating habit should be correctly educated to elementary students by spoken words and textbooks in a curriculum. In reality, snacks are classified as being the leading factor of obesity. Therefore more products containing balanced nutrition should newly develop rather than snacks with high fat content.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.123-140
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• 2013

The Dangdu Pb-Zn deposit is located at approximately 10 km south of Jecheon, Korea. Geology of Dangdu deposit area consists of Pre-cambrian metamorphic rocks, Ordovician sedimentary rocks, Jurassic and Cretaceous igneous rocks. The ore deposit is developed along the fracture trending $N20{\sim}40^{\circ}W$ in Ordovician limestone and is considered to be a skarn type ore deposit. The shape of ore bodies developed in the Dangdu ore deposit can be divided into lens-form(two ore bodies of -30 m level adit and one ore body of -63 m level adit) and pocket-form developed in -30 m level adit. Ore minerals observed in the ore deposits are magnetite, pyrrhotite, pyrite, chalcopyrite, sphalerite, galena, cosalite, marcasite, hessite, native Bi and bismuthinite. Chemical composition of sphalerite ranges FeS 14.14~18.08 mole%, CdS 0.44~0.70 mole%, MnS 0.52~1.13, 1.53~2.09 mole%. Galena contains a small amount of silver with an average of 0.54 wt.%. An average composition of cosalite is Ag 2.43 wt.%, Bi 44.36 wt.%, Pb 35.05 wt.% which results the chemical formula of cosalite as $Pb_{1.7}Bi_{2.1}Ag_{0.2}S_5$. Skarn minerals consist of epidote, garnet, pyroxene, tremolite, quartz and calcite. The zoning pattern of the ore deposit can be subdivided into epidote-clinopyroxene zone, epidote-clinopyroxene-chlorite zone and epidote-garnet-clinopyroxene zone from the central part of the ore body towards the wall rocks. The chemical composition of garnet shows an increasing trend of grossular from epidote-clinopyroxene zone to epidote-garnet-clinopyroxene zone. Clinopyroxene occurs as a solid solution of diopside and hedenbergite, and the ratio of johannsenite increases from epidote-clinopyroxene zone to epidote-clinopyroxene-chlorite and epidote-garnet-clinopyroxene zones. The mineralization of the ore deposit is considered to be one stage event which can be separated into early skarn mineralization stage, middle ore mineralization stage and late low temperature mineralization stage. The temperature estimation from the low temperature mineralization range from $125{\sim}300^{\circ}C$ which is considered to be representing the temperature of late mineralization.