• 환경생물
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• 제20권3호
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• pp.232-236
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• 2002

The morphological patterns and the cytopathogenicity time of the Vero cells induced by free $Cd^{2+}$ and pigment-bound $Cd^{2+}$ were observed by inverted microscope in order to investigate the difference of cadmium toxicity. The Vero cells induced by Hee $Cd^{2+}$ of 0.1 mM were shown to have a fatal toxic effect and the cytopathogenicity could be seen early after 6$\pm$2 hours of incubation. Partially affected cells induced by pigment-bound $Cd^{2+}$ of 0.1 mM were shown and the cytopathogenicity could be seen after 20 hours of incubation. The Vero cells grown with free 0.001 mM $Cd^{2+}$ were also affected and the cytopathogenicity could be seen after 17 hours of incubation, whereas the Vero cells grown with 0.001 mM pigment- bound $Cd^{2+}$ were unaffected. The sensitivity of Escherichia coli DH5$\alpha$ bacterial cells was also examined after a short treatment with free $Cd^{2+}$ or pigment-bound $Cd^{2+}$. About 5% of cells survived after 0.01 mM of free $Cd^{2+}$ treatment, while about 68% of cells survived after 0.01 mM of pigment- bound $Cd^{2+}$.

• 대한한의학회지
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• 제27권4호
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• pp.162-173
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• 2006

The water-extracts of Scutellaria barbata Don (SBDE) were isolated from Chinese medicinal plant sources. The extracts showed strong growth-inhibitory activity and cancer chemopreventive activity on the growth and DNA incorporation of MG63 human osteosarcoma and K562 human leukemia cell lines. The growth of human cancer cells was inhibited in the presence of the extracts (20, 50 and 100 ${\mu}$g/ml), and the effects were concentration-dependent and incubation time-dependent up to 8 days. When 50 ${\mu}$g/ml of the extracts was added to the media of MG63 and K562, cell growth after 8 days or 6 days of incubation was retarded by 93.2 to 97.3% of the control group. Morphological changes of MG63 and K562 cell lines were observed. As the concentration of the extracts increased up to 50 ${\mu}$g/ml, degree of cell aggregation decreased. Moreover, the DNA incorporation of the cells which were labeled with [3H] thymidine was significantly reduced after 3 days of incubation at $37^{\circ}C$ with the extract. Therefore, it is suggested that the extract is highly effective on inhibition of cancer cell growth. The extract also inhibited gene expression of IGF-II in transcriptional level. Since IGF-II works as a mitogenic effector on MG63 and K562 cell lines, these results suggest that the growth inhibition is in part mediated through the inhibition of IGF-II gene expression.

• Environmental Engineering Research
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• 제22권4호
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• pp.347-355
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• 2017

This study investigated how the combined changes in environmental conditions and nitrogen (N) deposition influence the mineralization processes and carbon (C) dynamics of wetland soil. For this objective, we conducted a growth chamber experiment to examine the effects of combined changes in environmental conditions and N deposition on the anaerobic decomposition of organic carbon and the emission of greenhouse gases from wetland soil. A chamber with elevated $CO_2$ and temperature showed almost twice the reduction of total decomposition rate compared to the chamber with ambient atmospheric conditions. In addition, $CO_2$ fluxes decreased during the incubation under the conditions of ambient $CO_2$ and temperature. The decrease in anaerobic microbial metabolism resulted from the presence of vegetation, which influences the litter quality of soils. This can be supported by the increase in C/N ratio over the experimental duration. Principle component analysis results demonstrated the opposite locations of loadings for the cases at the initial time and after three months of incubation, which indicates a reduction in the decomposition rate and an increasing C/N ratio during the incubation. From the distribution between the decomposition rate and gas fluxes, we concluded that anaerobic decomposition rates do not have a significantly positive relationship with the fluxes of greenhouse gas emissions from the soil.

• 한국양식학회지
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• 제20권3호
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• pp.194-198
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• 2007

Reproductive traits of Palaemon gravieri such as embryo size, number of embryo (fecundity), incubation period, larval development mode, larval development period, larval survival and larval growth were described and compared to analyze the correlation among those traits. Embryo volume is a primary factor determining other ensuing reproductive features. Egg volume was $0.042mm^3$ in the first developmental stage. Embryo volume in P. gravieri was comparatively small which is indicative of great number of embryo (y = 3.0161x + 0.0185 $R^2$ = 0.74 positive isometric relationship) and relatively long incubation period. Larvae survived from zoea 1 to post-larvae and it took 45 days at $22^{\circ}C$. Survival rate of the larvae was rather great in the early stage and thereafter steadily decreased. Daily growth rate of larvae in P. gravieri at $22^{\circ}C$ was 0.0195 mm on average. They grew steadily as time went by. Incubation period was between 10-14 days at $22^{\circ}C$. Larval development mode was almost complete planktotrophic. PNR (point of no return) appeared to be the third day on average. Survival rate of larvae without feeding declined rapidly between 3 and 4 days. Larval development period and stage frequency were 23-30 days and 11 stages which imply prolonged larval period and high mortality. The pattern of brood production followed fast successive parturial pattern. Most ovigerous female had mature ovary when they performed parturial molt soon after hatching (larval release).

• 한국인터넷방송통신학회논문지
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• 제8권5호
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• pp.243-249
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• 2008

디지털 정보 처리 기술과 통신 기술 및 방송 기술의 진보로 방통 융합의 시대가 열리고 있으며 산업 분야의 신성장 모델이 되고 있다. 본 논문에서는 방통 융합의 시대에서 이를 성공적으로 전개할 수 있는 요소 기술들을 분석하였으며, 이를 기반으로 창조적이고 능력 있는 전문 인력의 배출을 목표로 하는 대학에서의 인력 양성 알고리즘을 다루었다. 인력 양성 알고리즘에서는 요소 기술을 지원할 수 있는 기본적인 교육 과정과 차세대 인력 양성을 수행하는 대학에서의 이를 이용한 교육 방향 및 흐름도를 다룬다.

• The Korean Journal of Ecology
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• 제25권6호
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• pp.399-403
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• 2002

Cellulose mass loss by cellulose filter papers was measured for 3 time (35 days, 70 days, 105 days) incubation during the growing season (from May to September 2002) with different tree density and after fertilization in a Japanese larch (Larix leptolepis) plantation. Cellulose mass loss rates were significantly different between tree density types and fertilization treatments during the study periods. After 105 day incubation of cellulose filter paper, cellulose mass loss rates were significantly higher in the low tree density (70.1 $\%$) than in the high tree density (49.9$\%$). Cellulose mass loss rates averaged 62.8$\%$ in the fertilization and 58.9% in the unfertilization treatments during the same periods. However, cellulose mass loss was not significantly different between the forest floor and the mineral soil layer except for 35 day incubation. The results indicate that cellulose decomposition rates are a useful index to express differences in organic matter decomposition activity in different tree density and after fertilizer treatments.

• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.167-173
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• 1997

The inhibitory effects of kale juice on the growh and DNA incorporation of human cancer cells, using HT-29 colon cancer cells, MG-63 osteosarcoma cells, AGS gastric adenocarcinoma cells and K-562 leukemia cells, were studied. The growth of human cancer cells were inhibited in the presence of kale juice (10, 20 nd 40$\mu$l/ml) and the effects were the juice concentration- and incubation time-dependent up to 6 days. When 20$\mu$l/ml of kale juice was added to the media of HT-29, MG-63, AGS and K-562 cancer cells, the cell growth after 6 or 4 days of incubation was retarded by 83~95% of control group. Morphological changes of HT-29 colon cancer cells wre studied under inverted microscope. As the concentration of kale juice increased up to 20$\mu$l/ml, degree of cell aggregation was decreased. Moreover, the DNA incorporation o AGS gastric adenocarcinoma cells and MG-63 osteosarcoma cells which were labeled with [$^3$H] thymidine was significantly reduced after 2 days of incubation at 37$^{\circ}C$ with kale juice. Therefore, we concluded that kale juice strongly decreased the growth of various human cancer cells.

• 한국환경생태학회지
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• 제31권2호
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• pp.127-134
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• 2017

본 연구는 2013년 번식기 동안 광주광역시에서 제비의 번식행동을 밝히기 위하여 이루어졌다. 오전시간에 영소 빈도는 14.2~31.0 trips/h 범위, 성별로는 수컷 10.2~19.8 trips/h, 암컷 4.0~11.4 trips/h을 보였다. 영소 시간은 7.6~15.9 min/h 범위였고, 성별로는 수컷 4.8~8.1 min/h, 암컷 2.8~8.0 min/h 으로 조사되었다. 한 회 영소 시간은 수컷 $26.1{\pm}15.5sec/trip$, 암컷 $40.0{\pm}27.9sec/trip$으로 암컷이 수컷보다 약 1.5배 길었다(p<0.001). 포란은 암컷이 전담하였으며, 6h에 $50.6{\pm}17.5min/h$ (84%), 7h에 24.5 min/h(40.8%)이었고, 그 이후로는 대략 15.6 min/h (26.0%)로 조사되었다. 주간시간 암컷의 포란시간은 시간대별로 고도로 유의한 차이를 보였으며(p<0.001), 6h의 포란시간은 다른 시간보다 특히 높은 것으로 나타났다. 암컷의 포란시간과 평균 기온간에는 유의한 음의 상관관계가 있었다(p<0.05). 주간시간에 급이 빈도는 총 $385.2{\pm}66.9trips/nest$, 성별로는 수컷 $219.2{\pm}37.1trips/nest$, 암컷 $166.0{\pm}30.8trips/nest$으로 나타났다. 시간당 급이 빈도는 $32.1{\pm}12.3trips/h$, 성별로는 수컷 $18.3{\pm}7.8trips/h$, 암컷 $14.3{\pm}4.5trips/h$ 이었다. 시간당 급이 빈도는 성별로 10h(p<0.05)와 15h(p<0.01)에서 유의한 차이가 있었다. 한 회 급이 시간은 수컷 $12.3{\pm}31.0sec/trip$, 암컷 $40.9{\pm}83.3sec/trip$로 암컷이 수컷보다 유의하게 투자하는 것으로 나타났다(p<0.001). 새끼의 배변 빈도는 $45.6{\pm}8.4times/nest$이었으며, 급이 빈도와 양의 상관관계를 보였다(p<0.05). 본 연구의 결과는 한국의 서식환경에 적응하여 번식하는 제비의 번식행동학적 정보를 이해하는데 도움이 될 것으로 판단된다.

• 한국축산식품학회지
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• 제31권6호
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• pp.851-857
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• 2011

This study was conducted to develop a real time reverse transcriptase-PCR (RT-PCR) method for the detection of viable Enterobacteriaceae in milk using primers based on the genes of ribosomal proteins S11 and S13 and to determine effects of heating and subsequent treatments on the threshold cycle (Ct) of the real time RT-PCR. Total RNA was isolated from 17 strains of bacteria including 11 strains of Enterobacteriaceae suspended in milk using a modified Tri reagent method. SYBR Green Master Mix was added to the RNA and the mixture was subjected to the real time RT-PCR. The Cts of eleven type strains of the Enterobacteriaceae in milk ($10^7$ cells) in the real time RT-PCR ranged from 21.5 to 24.6. However, the Cts of Pseudomonas fluorescens, Acinetobacter calcoaceticus, and three gram-positive bacteria were more than 40. The real time RT-PCR detected as low as $10^3$ cells in agarose gel electrophoresis. The Cts increased from 22.0 to 34.2 when milk samples contaminated with Escherichia coli ($10^7$ cells/mL) were heated at $65^{\circ}C$ for 30 min. In addition, subsequent incubation at $37^{\circ}C$ for 6 and 24 h increased the Cts further up to 36.2 and 37.2, respectively. Addition of RNase A to the bacterial suspension obtained from the heated milk and subsequent incubation at $37^{\circ}C$ for 1 h increased the Cts to more than 40. The results of this study suggests that pretreatment of bacterial cells heated in milk with RNase A before RNA extraction might enhance the ability to differentiate between viable and dead bacteria using real time RT-PCR.

• 한국토양비료학회지
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• 제12권3호
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• pp.117-124
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• 1979

$^{32}P$로 표식(標識)된 $Ca(H_2P^*O_4)_2{\cdot}H_2O$를 사용(使用)해서 모재(母材)와 이용(利用) 형태(形態)가 상이(相異)한 토양(土壤)에 시용(施用)된 인산(燐酸)의 행동(行動)을 파악(把握)하기 위(爲)하여 시용(施用) $^{32}P$의 $A{\ell}$-P, Fe-P, Ca-P, 및 유기인산(有機燐酸)으로의 분배(分配) 양상(樣狀)과 Lancuster법(法)으로 침출(浸出)되는 $^{32}P$의 경시적(經時的) 변동상황(變動狀況)을 조사(調査)했던 결과(結果)를 용약(要約)하면 다음과 같다. 1) 하성(河成) 충적모재(沖積母材)에서 발달(發達)한 논 토양(土壤)(풍건토(風乾土), pH5.8 유효인산(有效燐酸) 100ppm에 인산(燐酸)을 시용(施用)하고 담수정온(湛水定溫)($25^{\circ}C$)하는 과정(過程)에서 초기(初期)(1~3주(週))에는 많은 부분(部分)의 시용인산(施用燐酸)이 $A{\ell}$-P*로 결합(結合) 하나 시간(時間)이 경과(經過)함에 따라 $A{\ell}$-P*와 Ca-P*로 결합(結合)됐든 인산중(燐酸中) 상당부분(相當部分)이 Fe-P*로 변환(變換) 되는것 같았다. 시용(施用)된 인산(燐酸)이 유기인산(有機燐酸)으로 되는 양(量)은 비교적(比較的) 적었고 그 양(量)은 경시적(經時的) 변동(變動)이 별로 없었으며, 유효인산(有效燐酸)으로 침출(浸出)되는 $^{32}P$양(量)은 담수초기(湛水初期)(1~3주(週))에는 시간(時間)의 경과(經過)에 따라 감소(減少) 했으나 그 뒤부터는 시간(時間)의 경과(經過)에 따라 증가(增加)하는 경향(傾向)이였다. 2) 화산회토(火山灰土)(pH, 5.2 유효인산(有效燐酸) 2.7ppm)에 인산(燐酸)을 시용(施用)하고 밭 상태(狀態)로 유지(維持)하면서 정온(定溫)한 경과(境過) 시용(施用)된 $^{32}P$는 Fe-P*에 특(特)히 많이 분배(分配) 됐으며 기간(時間)의 경과(經過)에 따른 각(各) 형태간(形態間)의 전환(轉換)은 별로 뚜렷하지 않았다. 특(特)히 이 토양(土壤)에서는 시용(施用) 인산(燐酸)의 유효인산(有效燐酸)으로의 침출양(浸出量)이 극(極)히 적었다. 3. 화강암풍화물(花崗岩風化物)을 모재(母材)로 하는 토양(土壤)의 경과(境過) 기경지(旣耕地)(pH5.2, 유효인산(有效燐酸) 4.8ppm) 또는 미경지(未耕地)(pH4.6, 유효인산(有效燐酸)은 7.3ppm)에 무관(無關)하게, 시용(施用) 인산(燐酸)은 초기(初期)(1~2주(週))에는 Ca-P에 많이 분배(分配) 됐지만 시간(時間)이 갈수록 Ca-P*와 $A{\ell}$-P는 줄고 Fe-P*가 증가(增加)하여, 무기인산(無機燐酸)의 형태간전환(形態間轉換)에 관(關)한 한답토양(限畓土壤)의 경우(鏡遇)와 유사(類似) 했다. 시용인산(施用燐酸)의 유효인산(有效燐酸)으로의 침출량(浸出量)은 두 토양(土壤) 공(共)히 많은 편(便)이였으며 경시적(經時的)으로 보면 기경지(旣耕地)의 경우(境遇)는 별로 변동(變動)이 없었으나 미경지(未耕地)에서는 시간(時間)이 경과(經過)와 함께 감소(減少)하는 경향(傾向)이 뚜렷했다.