• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.4
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• pp.360-373
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• 2006

The purpose of this research was to investigate whether pulsed electromagnetic field (PEMF) stimulation applied to the rabbit cranial defects grafted with ${\beta}$-tricalcium phosphate (${\beta}$-TCP) could affect the new bone formation. With 16 New Zealand white rabbits under the same condition, bilateral calvarial bone defects were formed around the sagittal suture line. The defect on the left side was grafted with ${\beta}$-TCP, while on the right side was grafted by harvested autogenous bone. PEMF was applied to 8 rabbits for 8 hours per day. The bony specimen were divided into 3 groups, the group 1 was autogenous bone grafted specimen, the group 2 was ${\beta}$-TCP grafted with PEMF, and the group 3 was ${\beta}$-TCP grafted without PEMF. We investigated the bone regeneration & growth factor expression at 2, 4, 6, and 8 weeks. As a result, BMP 2 was expressed in the group 1 from 2 weeks, the group 2 from 4 weeks, and the group 3 from 6 weeks. BMP 4 was expressed in the group 1 from 2 weeks, in the group 2 and the group 3 from 4 weeks. 4. There was no significant difference in expression pattern of BMP 7, PDGF, VEGF, and TGF-${\beta}$1 during grafted bone regeneration in group 1, 2, and 3. According to our results, PEMF stimulation could be effective on the new bome formation in animal study, and have a feasibility of clinical use.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.516-525
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• 2011

We studied the influence certain environmental factors (proximity of roosting site, roads, and residential areas) have on the spatial distribution of cranes in the Cheorwon, Korea. Using a range finder and GPS, data were collected from January to February 2007 and were subsequently evaluated with ArcGIS. The size of the cranes' wintering habitat was estimated to be 7$76.9km^2$. Five hundred and fifty-five flocks of cranes were observed and detailed distributions were collected. Feeding distribution of the cranes showed clustered distribution, however, no tendencies of spatial autocorrelation were apparent. Adjacent regions with paved roads and residences showed lower densities than other areas. Distances at which paved roads and residential areas induced changes in feeding flock densities were 1500m and 1750m, respectively. Feeding flock density decreased with increased distance from roosting site. Feeding flock density of the two crane species did not increase as distance from roads increased, however, the density of individuals showed a significant increasing tendency with increased distance from roads. In both species, density of feeding flocks and individuals significantly increased with increasing distance from residential areas. In Red-crowned Cranes, the density of feeding flocks and individuals significantly decreased with increasing distance from roosting site, however, in the case of White-naped Cranes, there was an even distribution in density of feeding flocks and individuals.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.469-476
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• 2020

This study is a qualitative study to grasp the meaning of the effective role of tutors of college students experiencing problem-based learning through focus group interviews. The subjects of this study were 4th grade students in the Department of Nursing who had experienced PBL, and a total of 21 people were divided into 3 groups and interviewed. Data were analyzed in content to find meaningful topics. The results of this study were analyzed into two subjects and eight categories. Based on the research results, if we summarize the role of effective tutors recognized by students in PBL. 1) Create a permissive atmosphere so that students can express their ideas freely and interact. 2) Give praise and encouragement. 3) Encourage all learners to participate. In particular, learners with low participation should be asked questions to promote active discussion. 4) Avoid unnecessary intervention and participate in the discussion together. 5) Adjust the learning speed and manage the time well. 6) Develop a scenario that meets the goals. 7) Classes are run around questions that can promote learners' thinking. 8) It plays a role of helping to form knowledge by providing positive feedback to learners' responses.

• Journal of Aquaculture
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• v.7 no.3
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• pp.151-158
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• 1994

To evaluate the reproductive ability of gynogenetic diploid male. Paralichthys olivaceus. histological analysis of testis. cytological analysis of spermatozoa and fertilization test with normal aggs were studied and the results are as follow; The gonads of gynogenetic diploid male were histologically normal. and many spermatozoa were observed in their testis. Number of spermatozoa from the control and gynogenetic diploid male were $2.58\times10^9$ and $2.42\times10^9$ cells per 1 ml of milt. respectively (P> 0.05). Amount of milt per kg body weight from the gynogenetic diploid male was significantly higher (P< 0.01) than that from the control male (8.3ml). Size and morphology from the two experimental groups were not different (P>0.05). More than $80\%$ of fertilization rates and hatching rates were observed when the eggs from the control were fertilized with the gynogenetic diploid male sperms.

• Journal of Aquaculture
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• v.10 no.4
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• pp.417-424
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• 1997

This study was carried out to investigate the effects of experimental formulated diets, commercial diets and natural diet(dried Undaria) on growth and body composition of Haliotis discus hannai. Experimental diets was formulated to provide 34.1% protein and 7.5% lipid, and prepared by different $CaCl_2$ concentration (5, 10 and 15%) and dipping time (10, 20 and 60 second) in solution. The juvenile abalone average weighing 0.3g were distributed in a flow-through aquarium system using a cmpletely randomized desing with 13 diets and 3 replictes per diet (50 abalone/tank), and fed diets for 17 weeks. The abalone fed the time nine experimental formulated diets and two commercial diets showed better growth performance than that of natural diets. No significant differences were found among abalone fed the experimental diets and commercial diets in survival rate, weight gain, soft body weight and soft body composition (P>0.05).

• The Korean Journal of Malacology
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• v.28 no.1
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• pp.7-12
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• 2012

The effect of water temperature on spawning induction, larval development, spat settling and its growth of the cockle shell, Fulvia mutica, were investigated to obtain the basic data for effective seed production. The eggs, which were randomly divided into 6 groups of water temperatures of 14, 17, 20, 23, 26 and $29^{\circ}C$, were transferred into 1 L beaker, respectively. The relationships between the water temperature and the required time (1/h, hour) by each egg developmental stage were calculated. Biological minimum water temperature and the cumulative water temperature until egg development of the veliger stage were calculated to be $0.1^{\circ}C$ and $397.3^{\circ}C$, respectively. The optimal water temperature for developmental bioassay of F. mutica was clarified to be $23^{\circ}C$. The required time for the embryo to become veliger larvae was 20 hours at $23^{\circ}C$.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1253-1257
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• 2010

강원도 홍천군 내면에 위치한 비점오염 관리지역의 강우시 유출 특성을 파악하고, 비교하기위해 연구를 수행하였다. 2009년 6월부터 2009년 11월까지의 연구기간 중 강우량이 비교적 많은 7회의 강우사상에 대하여 단위면적당 유출량, 유량가중평균농도, 단위면적당 오염부하를 비교하며, 분석하였다. 강우사상별 단위면적당 총 유출량은 저감시설의 설치 유 무에 따라 명확한 경향이 나타나지 않았다. 자운천 유역의 SS, TP의 유량 가중평균농도는 각각 4.0~1440.4 mg/L와 0.024~0.267 mg/L의 범위로 나타났으며, 덕두원 유역의 SS, TP의 유량가중평균농도는 각각 6.2~1001.1 mg/L, 0.039~0.226 mg/L의 범위로 나타났다. 지령골 유역의 SS, TP의 유량가중평균농도는 각각 3.4~1050.6 mg/L, 0.08~0.342 mg/L의 범위로 조사되었다. 10차, 11차, 12차, 26차의 SS 항목에서는 비점오염 저감시설이 설치된 자운천과 덕두원 유역에 비해 다소 높은 것으로 나타났으며, TP는 대부분의 강우사상에서 지령골의 유량가중평균농도가 높았다. 자운천의 강우사상에 따른 SS의 단위면적당 오염부하는 0.24~1,397.85 kg/ha의 범위로 나타났으며, 덕두원과 지령골에서 산정된 SS의 단위면적당 오염부하는 각각 0.06~1,236.78 kg/ha와 0.29~894.81 kg/ha로서 8차와 9차 강우사상을 제외한 나머지 강우사상에서는 비점오염 저감시설이 설치되지 않은 지령골에서 더 많은 양이 발생하였다. TP의 경우 자운천과 덕두원 유역의 단위면적당 TP 오염부하는 각각 0.0006~0.33 kg/ha와 0.0005~0.21 kg/ha의 범위로 나타났으며, 지령골 유역의 강우사상에 따른 단위면적당 오염부하는 0.003~0.29 kg/ha의 범위로서 저감시설이 설치된 자운천과 덕두원 유역보다 높게 나타났다. 단위면적당 오염부하에 기초할 때, 비점오염 저감시설이 설치된 소유역에서 SS와 TP 항목에 대한 저감효과가 나타났다. 하지만 짧은 모니터링 기간과 자료의 부족으로 인해 비교 및 분석의 한계가 있다고 판단된다. 본 연구는 지속적인 모니터링으로 더 많은 자료가 확보될 때 비점오염 저감사업의 효과를 극대화시킬 수 있는 방안을 제시 할 수 있을 것으로 사료된다.

• Food Science and Preservation
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• v.14 no.3
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• pp.308-314
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• 2007

To investigate effects of fermentation on volatile components, we analyzed volatile organic compounds of raw and fermented Rhus verniciflua S. bark. A 50%(w/v) sugar solution was used for fermentation. Volatile organic compounds of raw and fermented Rhus verniciflua S. were extracted by the simultaneous steam distillation and extraction(SDE) method, with a mixture of n-pentane and diethylether(1:1, v/v) and analyzed by gas chromatograph-mass spectrometer. A total of 51 and 27 volatile organic compounds were detected in raw and fermented samples, respectively, and were mainly alcohols. Compounds such as ethyl acetate, 2-methyl-3-buten-2-ol, 3-methylbutanal, 1-octen-3-o1, 3-methyl-2-butanone, hexanal and pentanal were detected as the primary compounds in the raw sample. The fermented sample showed sour different volatile compounds, such as ethanol, ethyl acetate, ethyl lactate and 3-methylbutanol. Thus, a number of volatile organic compounds were synthesized after fermentation of Rhus verniciflua S. bark.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.230-237
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• 2003

This study was conducted to investigate the occurrence and characterization of tobacco mosaic virus(TMV) in Chinese foxglove isolated from the field of the Chonbuk province(Jinan, Jangsu, Jeongeup). TMV was detected in all three regions and confirmed positive reaction by ELISA test. In the host range test, Chenopodium amaranticola, Nicotiana glutinosa, N. tabacum cv. 'Bright yellow', N. tabacum cv. 'KY­57, Datura stramonium were locally infected with the virus. The virus produced mosaic symptom on inoculated leaves of N. tabacum cv. 'Samson'. However, Chenopodium quinoa, Glycine max, Raphanus sativus, Cucumis sativus, Cucurbita moschata, Brassica rape and Lycopersion esculentum did not show any symptoms. TMV particles were revealed as a stiff rod shape by transmission electron microscopic(TEM) and measured as 300 nm in length with 18 nm in diameter. Total RNA was extracted from showing symptom loaves infected with TMV and the reverse transcription­polymerase chain reaction (RT­PCR) obtained 531 bp DNA product of RNA with specific primer used. The capsid protein of TMV­RE showed higher amino acid sequence homology(97.7％) with TMV­To than with TMV­P(72.2％). The capsid protein of TMV­152 showed same amino acid sequence homology with TMV­F. The result of comparison of nucleotides sequence homology between TMV­RE strain and other TMV strain showed 94％ homology with others except TMV­P(67.3％) and TMV ­ C(68.6％).

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.176-182
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• 2006

Sensitive and specific monoclonal antibody (MAb) was produced from hybridoma (1H11-5) obtained by fusion of myeloma cell (V653) and spleen cell isolated from mouse immunized sulfamthazine (SMZ)-HG-KLH. Direct competitive ELISA was developed for rapid detection of SMZ in milk samples using MAb against SMZ with optimized conditions between MAb and SMZ-HG-HRP conjugate, and applicable conditions for analysis of milk samples were established. Detection range of immunoassay was 0.1 to 100 ppb. Recoveries from spiked raw milk and processed milk samples averaged 82.1-120.7 and 82.1-97.1%, respectively.