• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.239-246
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• 2013

This study observed changes of understory vegetation to evaluate the role of forest aggregate after 15% aggregated retention harvest in mature oak forest (> 100 years) in Gyungsangbukdo Bonghwagun in 2010 and 2011. Spontaneous responses of understory vegetation cover (%), species richness, abundance of plant growth forms (herbaceous and woody plants), and overall attributes (by Ordination analysis) were estimated in aggregate area (0.15 and n=36) and clear cut area (0.85 and n=192) in experimental site and control site (1 and n=300). Based on ordination analysis, overall change of species composition in aggregated sites were relatively lower than in harvest area. Right after treatment, total cover of cutted area slightly decreased from 15.6% to 14.7%, and species richness increased from 14 species to 22 species. Cover and richness in the both of aggregate and control sites increased. In plant growth forms, 15% aggregate harvest revealed positive effects on the abundance (cover and richness) of herbaceous plants than woody group. After retention treatment, overall, edge effect likely played major component of vegetation changes in aggregate forest and in harvested area, mechanical damage from harvest operation and change of forest structure by clear cutting were critical. As pre-treatment data, which are rare in ecological studies in Korea, were critical for interpretation between patterns that may have arisen from spatial distributions in the original forest, our experimental design have higher opportunity for long term monitoring on the effect of forest aggregate and vegetation regeneration in clear cutted area.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.31 no.4
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• pp.121-144
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• 2020

The purpose of this study is to suggest the site selection of U-library in Daejeon. For this study, through literature research and analysis of the current status of U-library in Korea, evaluation indicators for the site selection are derived, and based on this, the location of the public library, the radius of the proposed location, the transport performance by subway station, government offices, transportation facilities, convenience facilities, the current status of major facilities and the number of residents by region were analyzed and applied. Finally, based on the analysis results, a total of 16 U-library locations were proposed in the five autonomous districts in Daejeon: 2 in Daedeok-gu, 2 in Dong-gu, 4 in Seo-gu, 6 in Yuseong-gu, and 2 in Jung-gu.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2000.11a
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• pp.20-20
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• 2000

2개의 경사 충격파와 하나의 수직 충격파로 초음속 유동을 압축하는 초음속 공기 흡입구의 수치적 연구를 수행하였다. 지배방정식으로는 Navier-Stokes방정식을 사용하였고 난류모델로는 SST 모델을 사용하였다. 지배방정식의 점성항 계산에는 중심차분법을 사용하였고 대류항 계산에는 풍상차분법인 Roe의 FDS기법을 MUSCL기법과 결합하여 이용하였다. 유한 체적법을 이용하여 차분된 방정식은 LU분할 기법을 이용한 완전 내재적 방법으로 2차 정확도 시간 적분으로 비정상 과정의 연구를 수행하였다. 흡입구 배압을 정해주어야 하는 어려움을 해결하기 위해 흡입구 후면에 노즐을 달고 노즐의 면적을 조절하여 배압이 형성되도록 하였다.(중략)

• Korean Journal of Animal Reproduction
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• v.21 no.2
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• pp.167-176
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• 1997

This study was carried out to evaluate the potential for preselection of transgenic embryos prior to transfer into recipient animals. In these experiments, I used a 3.2 kb transgene which contained the neomycin resistance gene (neo) and lac Z gene driven by the $\beta$ actin promoter (iacZ Ineo). Oocytes were aspirated from abattoir ovaries, matured in TCM-199 supplemented with 10% fetal bovine serum (FBS), 5 ${\mu}\textrm{g}$/ml LH, 0.5 ${\mu}\textrm{g}$/ml FSH, 100 unit/ml penicillin, and 100 ${\mu}\textrm{g}$/ml streptomycin for 22 to 24 hrs then inseminated with a sperm suspension of 1 X 10$^6$ sperm/ml containing 5 ${\mu}\textrm{g}$/ml of heparin. At 18-20 hrs after insemination, cumulus cells were removed by vortexing and pronuclei of centrifuged zygotes microinjected with the lacZ/neo construct (3 ng/$\mu$l). All cultures were carried out in CR1aa with transfected BRL monolayers containing 3 mg/ml BSA, 20 $\mu$/ml NEM amino acids and 40 $\mu$I/ml BME amino acids. To identify the appropriate concentration of G418 for selection, non-microinjected zygotes were cultured in the presence of 0, 50, 100 and 200 $\mu$g/ml of G418. After 8 days of culture in these treatments, 44/145 (30.3%), 13/150 (8. 7%), 1/151 (0.7%) and 0/134 (0.0%) devel-oped to the blastocyst stage in 0, 50, 100 and 200 $\mu$g/ml of G418, respectively. A total of 1,127 zygotes were microinjected and placed into culture (without G418) and subsequently 710 (63.0%) cleaved. At 48 hrs post-injection, embryos ($\geq$2-cell) were randomly assigned to control (medium alone) or G418 (100 ${\mu}\textrm{g}$/ml) treatments. A control culture of 740 non-microinjected embryos from the same replicates of embryos were also placed into control medium. After 8 days in culture, 54/343 (15.7%) and 22/367 (6.0 %) of the microinjected embryos developed to the blastocyst stage in control and G418 media, respectively. A total of 151/740 (27.2%) of the non-microinjected embryos placed in the control medium developed to the blastocyst stage. The blastocysts in the control treatment had a mean of 70.7 ${\pm}$ 4.7 cells of which 23.1 ${\pm}$ 2.6 (32.7%) stained for $\beta$-Gal activity. B1astocysts in the G418 treatment had a mean of 48.8${\pm}$7.5 cells of which 40.3 ${\pm}$ 4.1 (82.6%) stained for $\beta$-Gal ac tivity (P<0.05). In the control treatment 26 of 30 (87.0%) blastocysts had some cells with $\beta$-Gal activity while all of the blastocysts in the G418 treatment had some cell with $\beta$-Gal ac tivity (P<0.05). However, ICM colonies in either control or G418 treatments were not expressed any epiblast cell except of trophetoderm celIs. The $\beta$-actin promoter/lacZ gene may not be e expression or silence expression in epiblast cells These results clearly show an enrichment of blastocysts expressing the transgene in the majority of their cells after culture in the presence of G418. The exogeneous gene was not express a and silence in ICM colonies especiallly epiblast cells except of trophectederm cells. Even though the higher rate cell number expressed of exogeneous gene in the G418 treatments, a total cell number was decrease significantly (P<0.05) of which might be also drop of the establishment of ES like-cell colonies and production of transgenic animals. However, futher studies need to determine the viability of these selected embryos and the avability of production of transgenic offspring.

• Journal of Life Science
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• v.23 no.8
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• pp.998-1003
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• 2013

The effects of oral administration of estradiol-$17{\beta}$ (E2) on glass eels (Body weight: $0.16{\pm}0.05g$, Total length: $6.2{\pm}0.9cm$) and young eels (Body weight: $2.6{\pm}0.6g$, Total length: $13.2{\pm}0.6cm$) on gonadal sex and growth were examined, respectively. Glass eels were fed a diet containing E2 at a dose of 10 mg/kg or 25 mg/kg, respectively, for five months. The female ratio significantly increased in all E2-treated groups (10 mg/kg diet group: 70%; 25 mg/kg diet group: 90%) when compared to the control group (10%). Young eels were fed a diet containing E2 at a dose of 25 mg/kg for four months. The female ratio also significantly increased in the E2-treated groups (60%) compared to the control group (20%). The highest female ratio was observed in the stage of glass eels rather than young eels. In all experiments, however, the growth of eels treated with E2 was similar to that of controls to the end of the experiment. Thus, oral administration of E2 could be a good approach to controlling sex differentiation.

• Journal of Plant Biology
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• v.38 no.1
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• pp.47-54
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• 1995

The present study performed the isolation of cytosolic ascorbate peroxidase (APX) isozymes and analyzed the pattern of their activity development and also investigated the change in some other enzyme activities related to the ascorbate-glutathione pathway from the senescing wheat leaves. The aim of this work is to examine the possibility that in the cytoplasm of wheat leaves the ascorbate-glutathione pathway p!ays a significant role in relation to leaf senescence involving an $H_2O_2$ accumulation and then to show the effect of benzyladenine (BA) on that pathway. During the leaf senescence characterized by increases in ChI breakdown and H202 accumulation under the 4-day dark incubation of matured leaf segments; i) no significant increase of total cytosolic APX was observed, ii) a dehydroascorbate reductase (DHAR) activity was decreased rapidly, iii) a slight increase of glutathione reductase (GR) activity occurred. In the BA-treated leaves; however, i) the total activity of APX increased conspicuously, ii) the decrease of DHAR activity was relatively inhibited, iii) the GR activity increase was more enhanced, and iv) the decrease of ascorbate content and the increase of H202 content were retarded as compared with those of control leaves. Three isozymes of cytosolic APX were found by using a native-electrophoretic gel in senescing wheat leaves and two of them occurred with major activity. In the developmental patterns of cytosolic APX isozymes, only two isozyme bands ("a" and "b") appeared with almost constant activity through 4 days of incubation in the control leaves, while one additional weak isozyme band ("c") and a little increase of "b" isozyme activity were detected in the BA-treated leaves. EspeciaUy, the development of "a" isozyme activity increased remarkably compared with that of control leaves. The increased capacity for peroxide scavenging due to the enhanced activity of all 3 enzymes (APX, DHAR, GR) participating in the ascorbate-glutathione pathway in BA-treated leaves suggested that this pathway might playa significant role in the processes related to the wheat leaf senescence.scence.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2000.10b
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• pp.46-52
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• 2000

Performance of direct seeded upland field Schizonepeta tenuifolia Briquet in Southern areas of Korea was evaluated at different seeding methods (drilling and broadcasting) and seeding rates (1.5, 2.0, 3.0 and 3.5$\ell$/10a). There were no differences in the yield components such as length of stem and ear diameter of stem number of branch, internode and ear, and yield of fresh and dry stem between the seeding methods with drilling and broadcasting, but yield components such as length of stem and ear, diameter of stem, number of brench, internode and ear, and yield of fresh and dry stem increased with seeding rates of from 2.5$\ell$/10a to 3.5$\ell$/10a. Therefore optimum rates and methods of sowing were from 2.5$\ell$/10a to 3.5$\ell$/10a with seeding at the drilling and broadcasting.

• Korean Journal of Plant Tissue Culture
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• v.24 no.1
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• pp.43-48
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• 1997

Apical meristems of Wasabia japonica were cultured on Murashige and Skoog's medium supplemented with cytokinins alone or together with 1.0 mg/L IAA. Shoot initials could be induced from leaf primordia on apical meristems. Calli and roots were formed on the medium containing cytokinins and 1.0 mg/L IAA in combination after 30 days of culture, but there were no callus proliferation. Shoot organogenesis began after 60 days of culture and these small shoots elongated when transferred to a medium containing 1.0 mg/L BA or kinetin. Shoots were formed directly without callus induction from apical meristems all the explants on the medium containing cytokinins variously, and most of the shoots proliferated multiple shoots which could be divided to obtain plantlets. Shoot multiplication rate in response to cytokinins was best on the medium containing 1.0 mg/L BA or 2.0 mg/L zeatin. Divided plantlets rooted well on MS medium containing 0.01 mg/L IBA after 15~30 days of subculture and the rooted plantlets developed into whole plants with multiple shoots. After rooting, the regenerated plants were washed and transferred to the pots containing sterilized soil.

• Electric Engineers Magazine
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• v.220 no.12
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• pp.14-22
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• 2000

중국의 지역구분 및 개념은 제7차 경제개발5개년계획기간에 동부 연해지역 발전을 가속화하기 위한 전략에서 출발하였으며 이 때 동부, 중부, 서부지역으로 지역구분을 하였다. 동부지역은 요녕, 북경, 천진, 하북, 산동, 강소, 상해, 절강, 복건, 광동, 광서, 해남 등 12개 성, 시, 자치구로 구성되었고 중부지역은 산서 내몽고, 길림, 흑룡강, 안휘, 강서, 하남, 호북, 호남 등 9개 지역이며 서부지역은 섬서, 감숙, 청해, 영하, 신강, 서장, 운남, 귀주, 사천, 중경 등 10개 지역으로 구성되어 있다.

• Journal of the korean veterinary medical association
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• v.44 no.11
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• pp.1025-1033
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• 2008

이번 고병원성조류인플루엔자(이하 HPAI로 기술)는 2008년 4월 1일 우리 전라북도 김제시 용지면 산란계 밀집 사육지역에서 시작하여 5월 12일 경북 경산시 토종닭 농장을 끝으로 11개 시 도 19개 시 군 구에서 총 33건이 발생되어 2,6410억원의 경제적 피해가 발생하였다. 우리 전라북도는 최초 발생농가를 포함 4개 시 군(익산, 정읍, 김제, 순창)에서 17건(닭13, 오리 4)이 발생하여 전국에서 HPAI발생이 가장 많았던 도로 남는 불명예를 안게 되었다. 이에 막대한 경제적 피해가 다시 발생하지 않도록 HPAI의 현장 방역에 대해 나름대로 경험한 것과 느꼈던 것들을 사례별로 기술하고자 한다.