• Title/Summary/Keyword: Science Education

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Ore Minerals, Fluid Inclusions, and Isotopic(S.C.O) Compositions in the Diatreme-Hosted Nokdong As-Zn Deposit, Southeastern Korea: The Character and Evolution of the Hydrothermal Fluids (다이아튜림 내에 부존한 녹동 비소-아연광상의 광석광물, 유체포유물, 유황-탄소-산소 동위원소 : 광화용액의 특성과 진화)

  • Park, Ki-Hwa;Park, Hee-In;Eastoe, Christopher J.;Choi, Suck-Won
    • Economic and Environmental Geology
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    • v.24 no.2
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    • pp.131-150
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    • 1991
  • The Weolseong diatreme was temporally and spatially related to the intrusion of the Gadaeri granite, and was -mineralized by meteoric aqueous fluids. In the Nokdong As-Zn deposit, pyrite, aresenopyrite and sphalerite are the most abundant sulfide minerals. They are associated with minor amount of magnetite, pyrrhotite, chalcopyrite and cassiterite, and trace amounts of Pb-Sb-Bi-Ag sulphosalts. The AsZn ore probably occurred at about $350^{\circ}C$ according to fluid inclusion and compositional data estimated from the arsenic content of arsenopyrite and iron content of sphalerite intergrown with pyrrhotite + chalcopyrite + cubanite. Heating studies of fluid inclusions in quartz indicate a temperature range between 180 and $360^{\circ}C$, and freezing data indicate a salinity range from 0.8 to 4.1 eq.wt % NaCl. The coexisting assemblage pyrite + pyrrhotite + arsenopyrite suggests that $H_2S$ was the dominate reduced sulfur species, and defines fluid parameter thus: $10^{-34.5}$ < ${\alpha}_{S_2}$ < $10^{-33}$, $10^{-11}$ < $f_{S_2}$ < $10^{-8}$, -2.4 < ${\alpha}_{S_2}$ < -1.6 atm and pH= 5.2 (sericte stable) at $300^{\circ}C$. The sulfur isotope values ranged from 1.8 to 5.5% and indicate that the sulfur in the sulfides is of magmatic in origin. The carbon isotope values range from -7.8 to -11.6%, and the oxygen isotope values from the carbonates in mineralized wall rock range from 2 to 11.4%. The oxygen isotope compositions of water coexisting with calcite require an input of meteoric water. The geochemical data indicate that the ore-forming fluid probably was generated by a variety of mechanisms, including deep circulation of meteoric water driven by magmatic heat, with possible input of magniatic water and ore component.

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Environmental Change of High Moor in Mt. Dae-Am of Korean Peninsula (대암산 고층습원의 환경변천)

  • Yoshioka, Takahito;Kang, Sang-Joon
    • Korean Journal of Ecology and Environment
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    • v.38 no.1 s.110
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    • pp.45-53
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    • 2005
  • The environmental change of Yong-nup in Mt. Dae-Am, which is located at the northern part of Kangwon-Do, Korea, was assesed with peat sedimentary carbon and nitrogen isotope analysis. The surface layer of the peat (0 ${\sim}$ 5 cm) was 190 year BP, and the middle layers (30 ${\sim}$ 35 cm and 50 ${\sim}$ 55 cm) were 870 year BP and 1900 year BP, respectively. Bulk sedimentation rate was estimated to be about 0.4 mm $year^{-1}$ for 0 cm to 30 cm and 0.15 mm $year^{-1}$ for 35 cm to 50 cm. The $^{14}C$ age of the bottom sediment (75 ${\sim}$ 80 cm) collected and measured in this study was about 1900 year BP, although it was measured that the $^{14}C$ of the lowest bottom sediment in Yong-nup was 4105 ${\pm}$ 175 year BP (GX-23200). Since the $^{14}C$ ages for 50 ${\sim}$ 55 cm and 75 ${\sim}$ 80 cm layers were almost the same as 1890 ${\pm}$ 80 fear BP (NUTA 5364) and 1850 ${\pm}$ 90 year BP (NUTA 5462), respectively, we have estimated that the deep layers (55 ${\sim}$ 80 cm) in the high moor were the original forest soil. The low organic C and N contents in the deeper layers supported the inference. The sediment of 50 ${\sim}$ 55 cm layer contains much sandy material and showed very low organic content, suggesting the erosion (flooding) from the surrounding area. In this context, the Yong-nup, high moor, of Mt. Dae-Am, might have developed to the sampling site at about 1900 year BP. The ${\delta}^{13}C$ values of organic carbon and the ${\delta}^{15}N$ values of total nitrogen in the peat sediments fluctuated with the depths. The profile of ${\delta}^{13}C$ may indicate that the Yong-nup of Mt. Dae-Am have experienced the dry-wet and cool-warm period cycles during the development of the high moor. The ${\delta}^{15}N$ may indicate that the nitrogen cycling in the Yong-nup have changed from the closed (regeneration depending) system to the open (rain $NO_3\;^-$ and $N_2$ fixation depending) system during the development of the high moor.

Clinical Characeristics of Intracordal Cysts (성대낭종의 임상적 특성)

  • Hong, Ki-Hwan;Park, Jung-Hoon;Kim, Won;Kim, Chang-Hyun
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.10 no.2
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    • pp.164-169
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    • 1999
  • Background and Objectives : The intracordal cysts are more increasingly diagnosed and treated due to advanced laryngeal stroboscopy and laryngeal microsurgical technique. The intracordal cysts are frequently misdiagnosed as vocal polyp or nodule The purpose of this study is to evaluate clinical features of intracordal cysts. Materials and Methods : In the present series, 83 cases of the intracordal cysts treated with laryngeal microsurgery are reported. The intracordal cysts are diagnosed preoperatively with indirect laryngoscopy, laryngeal endoscopy, laryngeal stroboscopy and confirmed with laryngeal microsurgical findings and biopsies. Results : Intracordal cysts are 83 of 1900 patients treated with laryngeal microsurgery(4.4%)-ductal cysts are 56 cases and epidermoid cysts are 27 cases. Intracordal cysts are more frequent in women, forties and the frequent site is an anterior third of the true vocal cord. With the indirect laryngoscopic examination, the ductal cysts are frequently misdiagnosed as vocal polyps or nodules but the epidermoid cysts are relatively easily diagnosed. The etiologic factors of the intracordal cysts are suspected as voice abuse and upper respiratory infection. The degree of postoperative voice satisfaction is similar to that of the vocal polyps. Conclusion : Intracordal cysts are frequently misdiagnosed as polyps or nodules, therefore preoperative stroboscopic findings and laryngeal microsurgical findings is important. An ideal treatment is to enucleate the cysts avoiding rupture of cyst and injury of lamina propria of the vocal cord.

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Vitamin D intake, serum 25OHD, and bone mineral density of Korean adults: Based on the Korea National Health and Nutrition Examination Survey (KNHANES, 2011) (한국 성인의 비타민D 섭취량과 혈중 25OHD 농도 및 골밀도와의 관련성 : 2011 국민건강영양조사 결과 재분석)

  • Kim, Mi-Yeon;Kim, Mi-Ja;Ly, Sun Yung
    • Journal of Nutrition and Health
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    • v.49 no.6
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    • pp.437-446
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    • 2016
  • Purpose: The purpose of this study was to estimate dietary intake of vitamin D and the relationship between serum 25-hydroxyvitamin D (25OHD) concentration and bone mineral density (BMD) in Korean adults using the 2011 data from the Korea National Health and Nutrition Examination Survey. Methods: Daily intake of vitamin D and ratio of subjects that consumed less vitamin D than adequate intake (AI) were estimated in 4,879 Korean adults. The relationship between daily intake of vitamin D and serum 25OHD and BMD were analyzed. Results: Average daily intakes of vitamin D were $3.84{\pm}0.23{\mu}g/day$ for men and $2.22{\pm}0.11{\mu}g/day$ for women. Approximately 72~97% of men and 80~99% of women consumed less than the AI of vitamin D for Koreans. Serum 25OHD concentration increased with age, and the ratios of serum vitamin D deficiency (< 20 ng/mL) were 47.8~81.1% for men and 59.4~92.8% for women. Average intake of vitamin D was higher in subjects aged < 50 yr than in those ${\geq}50yr$, but lower in serum 25OHD concentration. In subjects aged < 50 yr, serum 25OHD was higher in subjects that consumed $10{\mu}g/day$ of vitamin D than in those that consumed less than $5{\mu}g/day$. In female subjects aged ${\geq}50yr$, average intake of vitamin D was associated with higher bone mineral density. Conclusion: It was found that dietary intake of vitamin D could increase serum 25OHD concentration in young adults and bone mineral density in old women. Therefore, nutrition policies for enriched foods with vitamin D and nutrition education to consume more vitamin D-rich foods are needed to ameliorate vitamin D status of the Korean population. Adequate intake for Korean population aged < 50 yr might be adjusted upwardly up to $10{\mu}g/day$.

Analysis and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in seafood from oil contaminated bay (유류 오염지역의 수산물 중 다환방향족탄화수소류 (PAHs) 분석 및 위해평가)

  • Jeong, Ji-Yoon;Choi, Chan-Woong;Ryeom, Tai-Kyung;Cho, Kyoung-Hee;Park, Se-Ryung;Shin, Ho-Sang;Lee, Kwang-Ho;Lee, Hyo-Min
    • Analytical Science and Technology
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    • v.23 no.2
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    • pp.187-195
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    • 2010
  • To assess health risk for the intake among residents after the Hebei Spirit oil spill, 16 Polycyclic Aromatic Hydrocarbons (PAHs) in seafood samples from oil contaminated bay were determined by Gas Chromatography-Mass Spectrometry (GC-MSD) and samples were personally collected and purchased by residents. Samples were hydrolyzed with KOH and extracted with methylene chloride. The extracted solution were cleaned up using silica/florisil column and 16 PAHs were eluted by methylene chloride : n-hexane (1:9) mixture and determined by GC-MSD in Selected Ion Monitoring (SIM) mode. The mean recoveries for 16 PAHs ranged from 79% to 85%. The 16 PAHs levels in 126 samples ranged from 0.17 to $6.04\;{\mu}g$/kg and the TEQBaP (Toxic EQuivalents) levels in 126 samples were calculated using benzo(a)pyrene toxic equivalency factor for individual 16 PAHs and ranged from 0 to $0.91\;{\mu}gTEQ$/kg. The average Benzo(a)pyrene dietary exposure of residents was $5.5{\times}10^{-8}\;mg/kg$ bw/day and the average PAHs chronic dietary exposure was $1.3{\times}10^{-5}\;mg$ TEQ/kg bw/day. The margin of exposure (MOE) and the excess cancer risk and were $1.8{\times}10^6$ and $9.8{\times}10^{-8}$, respectively. Therefore, the assessment result was considered as low concern for health risk.

A Study on the Degree of Satisfaction with School Dinner by School Meal Service in Daegu (대구지역 고등학생의 학교급식서비스 공급 유형에 따른 석식만족도 조사)

  • Lee, Eun-Ju
    • Culinary science and hospitality research
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    • v.18 no.4
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    • pp.277-291
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    • 2012
  • To compare satisfaction with school meals provided by two different types of school meal services, a survey was conducted with 252 high school students (male: 138, female: 114) consisting of 133 students offered by on-site school meal service and 114 ones by transporting school meal service in Daegu. Anthropometric measurements of the study subjects showed that 68.1% of male and 41.2% of female students had normal weight while 50.0% of female and 10.1% of male students were underweight on the basis of BMIs. 'Taste' was the most important factor when eating meals followed by 'nutrition', 'hygiene' and 'preference by the students'. (of the both schools). Eating habits of the subjects were influenced mostly by family. Female students (17.5%) skipped breakfast more frequently than the male students (8.0%). The students (68.4%) offered by on-site school meal service were more satisfied with meals than those (9.2%) by transporting school meal service. Top reason for not being satisfied was 'taste' in both schools but the second reason (36.3% of the subjects) was 'quantity of food' only in the school with transporting school meal service. In satisfaction with menu, temperature, quantity and hygienic condition of foods, higher dissatisfaction was shown in the students offered by transporting school meal service. Items needed for improvement in school meals suggested by the students were 'taste of food' (25.6% vs 62.2%), 'diversity of menu items' (21.1% vs 8.4%), 'hygienic conditions' (17.3% vs 8.4%), 'quantity of food' (10.5% vs 17.6%) and 'balanced nutrition' (8.4% vs 1.7%) for on-site service and transporting one. It is concluded from these results that transporting meal service for school meals has to be changed from the present condition to improve the quality of meals and that managing and supporting programs should be developed by public institutions such as office of education.

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A Study on the Sexual Adjustment and Quality of Life in Married Men with Spinal cord Injuries (척수장애 기혼남성의 성 적응과 삶의 질에 관한 연구)

  • Kim, Yeong-Hee;Cho, Bok-Hee
    • The Korean Journal of Rehabilitation Nursing
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    • v.3 no.1
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    • pp.27-42
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    • 2000
  • The purpose of this study was to identify the degree of sexual adjustment and quality of life in married men with spinal cord injuries and to furnish primary data to sexuality rehabilitation nursing practice which can lead to ideal sexual life and quality of life those men with SCI. Seventy married men with SCI were conveniently sampled in Kwangju, Suncheon, Mokpo and Seoul for responding the questionnaire, which was based on this research. With the research scale, SIS (Sexual interest and satisfaction) by Siosteen et al.(1990) and SB(Sexual behaviour) by Kreuter et al.(1996) were used for the measurement of sexual adjustment. And, for measuring quality of life was used SCI QL-23(Spinal cord injury of life-23) scale by Lundqvist et al.(1997). Data were collected from January 20 to March 20, 1999, using a structured questionnaire. A hundred volumes of questionnaire were used. and 85 volumes were collected, 70 volumes were used as research data after excluding 15 volumes unsuitable to data analysis. The obtain data were analysed using percentage, t-test, ANOVA, Duncan test, and Pearson's correlation by SAS PC+ program. The results were as follows: 1. The mean score of sexual interest and satisfaction of the subjects was 8.42. out of 18. The ways of their sexual behavior after spinal cord injuries were embracing and caressing (62.9%), kissing(58.6%), caressing breast with hands (55.7%), caressing breast with hands (52.9%), caressing genitals with hands (37.2%), caressing genitals with mouth(30.0%) and sexual intercourse (18.6%). The mean score of quality of life was 52.53 out of 100. 2. Age(F=3.24, p=.045) and caregiver (F=4.02, p=.022)were major variables which reveals significant differences in terms for sexual interest and satisfaction. The later results on Duncan's test showed that subjects who were in their 30s or 40s were significant higher than subjects whose age were in their 50s in their sexual interest and satisfaction. Also subjects with their spouse's care or mother's care were higher than those with other's care. 3. Subjects with incomplete paraplegia were higher than those with the complete paraplegia in sexual interest and satisfaction (F=3.01, p=.036). 4. Variables that showed the significant differences in the quality of life were education(t=2.860, p=.007) and period of marriage(t=2.125, p=.037). and occupational status(t=-2.161, p=.034). High school graduates, those who married before spinal cord injuries and those who didn't have occupation were higher than the other subjects. 5. Variables that revealed significant differences in the quality of life were time passage after spinal cord injuries(F=8.72, p=.001) and injured level of spinal cord(F=3.32, p=.042). Duncan's test showed that subjects who had lived for less than 4 years were higher those with time passage of 5-9 years and 10 years. Also subjects with lumbar injuries were higher than those with thoracic injuries in terms of quality of life. 6. There was negatively correlated between sexual interest and satisfaction and quality of life(r=-.256, p<.05). As a result of these findings sexuality rehabilitation for individuals with SCI was very important issue for their quality of life. Thus, registered nurses who care clients with SCI should activily participate in the client's sexual needs. Also, various sexual behaviors as well as sexual intercourse should be encouraged for the sexual adjustment of client's with SCI.

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Study for Habitat Usage of Spot-billed Duck in Korea, Using GPS-Mobile Telemetry (WT-200) (위치추적기(WT-200)를 이용한 흰뺨검둥오리의 서식지 이용에 관한 연구)

  • Shin, Yong-un;Shin, Man-Seok;Lee, Han-soo;Kang, Yong-myung;Moon, Oun-Kyong;Park, Hong-shik;Oh, Hong-shik
    • Korean Journal of Environment and Ecology
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    • v.30 no.2
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    • pp.146-154
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    • 2016
  • In this study, understanding the habitats on spot-billed duck that wintering-breed in the korea, which using the GPS-Mobile based Telemtry (WT-200), I tried to take advantage as the basic data of the protection and management of the habitats of the waterbirds of Korea. Study area is Gyeonggi-do Bokhacheon, Chonmichon, Chungcheongnam-do Gokugyochon, Chungcheongbuk-do Byeongcheoncheon, Jeollabuk-do Mangyunggang, which Five rivers and Jeju Island reservoir, I have attached the tracking of the location(WT -200) to the twenty-five spot-billed ducks. among twenty five ducks, twelve ducks moved to overseas countries, the arrival site was China, North Korea, Russia. Moving average distance was 683km, the largest distance was 1,238km. The average northbound starting date was April 26. The average daily movement distance of thirteen ducks remaining in the domestic country is $1.0{\pm}0.89km$, maximum travel distance was 23.8km. The average daily movement distance of wintering prior to average going north dating is a 0.9km, is the largest 14.6km, the breeding season is an average 1.3km, maximum was 14.4km. Spot-billed duck used the rivers in domestic country most frequently, following was rice field, a filed, reservoir. It used the river most frequently during the wintering period, in the breeding season it used paddy paddies most frequently. While wintering, during the day and night's utilization rate was the highest in the river, but utilization rate was incleased on filed, paddy filed at night. During breeding season, daytime and night's utilization rate was the highest but, utilization rate was increased on river and utilization rate was decreased on river. In accordance with time change, spot-billed duck showed different tendency in paddy fields, and they utilized the filed adjacent to rivers mostly.

Home-Range of Mallard and Spot-billed Duck in Korea (청둥오리와 흰뺨검둥오리의 월동기 행동권 비교 연구)

  • Shin, Yong-un;Shin, Man-Seok;Lee, Han-soo;Kang, Yongmyung;Jeong, Wooseog;Choi, Jida;Yoon, Hachung;Oh, Hong-shik
    • Korean Journal of Environment and Ecology
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    • v.30 no.2
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    • pp.165-172
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    • 2016
  • Mallard and Spot-billed ducks that are typical wintering water birds use the wide rice field in the center of the water system as a wintering ground. I try to figure out the daily movement distance from Home-Range to wintering ground for mallard and spot-billed ducks in Mangyunggang, Dongjingang where located in central region. In 2015 wintering period by using a Cannon-net, I attached WT-300 to 5 mallard and 5 spot-billed ducks. Daily movement distance is an overall average 0.89km, the largest distance was 31.09km. Daily movement distance of mallard was 0.97km, the largest distance was 28.78km. Daily movement distance of Spot-billed ducks was 0.80km, the largest distance was 33.39km. Home-Range analysis is used by the SHP files that is compatible with GIS and ArcGIS 9.0 Animal Movement Extension, it was analyzed using the Minimum Convex Polygon Method (MCP) and the Kernel Density Estimation (KDE). The behavior rights of two kinds of ducks was $490.34km^2$ by Minimum Convex Polygon Method (MCP) ($SD=311.20km^2N=10$), an important habitats Kernel Density Estimation (KDE 50%) was $42.24km^2$. Home-Range of Mallard (MCP) was $568.02km^2$, it is wider than home-range(MCP) of spot-billed duck $397.13km^2$ relatively, the core habitats of mallard is $53.05km^2$, it is wider than mallard's core habitats(KDE 50%) $29.26km^2$ relatively.

Comparison of the Bacterial and Fungal Colonies from Rana dybowskii which Collected from Inside and Outside Frog Farms and Identification of the Bacteria from the Tadpoles (개구리 증양식장 내·외부에서 채집된 북방산개구리(Rana dybowskii)로부터 검출된 세균과 곰팡이 콜로니 수의 비교 및 유생으로부터 확인된 세균 규명)

  • Kwon, Sera;Park, Daesik;Choi, Woo-Jin;Park, Jae-Jin;Cho, Han-Na;Han, Ji-Ho;Lee, Jin-Gu;Koo, Kyo-Soung
    • Korean Journal of Environment and Ecology
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    • v.31 no.5
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    • pp.444-454
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    • 2017
  • There are many ongoing studies of infectious diseases as the major factor responsible for global declining of the amphibian population. Although some point out the amphibian rearing facilities like frog farms as one of the important sources of harboring and spreading amphibian infectious pathogens in the wild, there have been few related studies in South Korea. In this study, we investigated the bacterial and fungal colonies on the skin and in the internal organs of frogs and tadpoles collected inside and outside of Dybowski's brown frog farms in Inje, Goesan, and Gongju to compare the difference according to the region and between inside and outside the farm. We also intended to classify the bacteria collected from the tadpoles into species by analyzing 16s rDNA gene sequences. The result showed that the number of bacterial colonies found in the skin and gut of frogs and the number of fungal colonies found in the skin and liver of frogs collected in Goesan was significantly greater than those in the frogs in Inje. However, there was no difference between the frogs collected inside and outside of farms in both regions. In the case of tadpoles, the number of fungal colonies in the tadpoles collected from Gongju was greater than that in the tadpoles collected from Inje. The comparison of inside and outside frog farms showed that there were more bacterial colonies on the skin of the tadpoles collected from inside than outside the frog farm in Inje and more bacterial colonies in the organs of the tadpoles collected from outside than inside the farm in Gongju. The frogs with higher condition factor (body weight/snout-vent length*100) showed fewer bacterial colonies on the skin and fewer fungal colonies in the heart, but there were no significant relationships in tadpoles. We identified the total of 15 genera and four phyla of bacteria, but the difference according to regions and between inside and outside farm was not evident. The result of this study indicates that the different conditions according to the locality of farm and between inside and outside farm cause the difference in the population sizes of bacterial and fungal colonies and that it can affect the overall health condition of Dybowski's brown frogs in the farm. Moreover, the result suggests that effective disease control in the facility is greatly necessary to ensure successful operation of amphibian rearing facility and to prevent the possible spread of diseases from the facility to the wild.