• Radiation Oncology Journal
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• 제21권3호
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• pp.216-221
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• 2003

목적: Cyclooxygenase-2 (COX-2)를 과발현하는 A549 인간폐암세포주와 발현하지 않는 MCF-7 인간유방암세포주에서 선택적 COX-2 억제제인 celecoxib의 방사선 감수성 증진 작용을 관찰하고자 하였다. 대상 및 방법: A549 세포와 MCF-7 세포에 대해서 방사선 혹은 방사선과 celecoxib를 병용 투여한 후에 clonogenic radiation survival 실험을 시행하였다. 같은 실험을 각각 $10\%$와 $1\%$의 FBS를 포함한 배지에서 반복하였다. 각 세포에 방사선과 celecoxib를 동시 혹은 단독 투여한 후에 각 실험 그룹의 세포사멸을 측정하였다. 결과: 약물 투여 기간 동안 $10\%$의 혈청을 포함한 배지 조건에서 배양된 A549세포에서는, $30\muM$과 $50\muM$ 농도의 celecoxib가 투여된 상태에서 surviving fraction=0.1에서의 Radiation enhancement ratio (RER)가 각각 1.58과 1.81로 celecoxib가 A549 세포의 방사선 감수성을 증가시켰다. 이러한 방사선 감수성의 증가는 세포를 $1\%$의 혈청을 포함한 배지에서 배양하였을때는 소실되었다. MCF-7 세포에서는 $10\%$와 $1\%$ 혈청을 포함한 각각의 배지조건 하에서celecoxib에 의한 방사선 감수성의 변화가 관찰되지 않았다. A549와 MCF-7 세포의 각 그룹에서 세포사멸을 측정한 결과 celecoxib와 방사선이 병용 투여되었을 때 유도되는 세포사멸은 상호 상승적이지 않은 것으로 나타났다. 결론: COX-2 선택적 억제제인 celecoxib는 COX-2를 과발현하는 A549 세포에서 선택적으로 방사선 감수성을 증진시켰으며, 저농도의 혈청을 포함한 배지 조건에서는 이러한 효과가 소실되었다. COX-2를 발현하지 않는 MCF-7 세포주에서는 celecoxib에 의해서 방사선 감수성이 변화되지 않았으며, 이러한 celecoxib의 방사선 감수성 증진 작용 기전에 세포 사멸은 관여하지 않는 것으로 보인다.

• Journal of Plant Biotechnology
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• 제7권4호
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• pp.211-218
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• 2005

Genetic transformation was carried out by using biolistic gun method. The hypocotyl derived embryogenic calli (explants) of cotton (Gossypium hirsutum L.) cv. Cocker-312 were transformed with a recombinant pGreen II plasmid, in which both, bar (selection marker) and GUS (${\beta}$-glucuronidase) reporter genes were incorporated. Explants were arranged on osmoticum-containing medium (0.5M mannitol) 4 hours prior to and 16 hours after bombardment that was resulted into an increase about >80% for GUS stable expression. 3 days after bombardment, GUS assay was performed, which exhibited, $18.36{\pm}1.00$ calli showed blue spots. The transformed embryogenic calli were cultured on selection medium (@ 6 mg/L basta) for 3 months. The putative transgenic plants were developed via selective somatic embryogenesis (@1.50 mg/L basta); maximum $27.58{\pm}1.25$ somatic embryos were obtained while $17.47{\pm}1.00$ embryos developed into plantlets (@ 0.75mg/L basta). In five independent experiments, up to 7.24% transformation efficiency was recorded. The presence of the transgenes was analyzed by using PCR and southern hybridization analysis. The transgenic plants were developed with in 6-7 months, but mostly transformants were abnormal in morphology.

• 한국산업정보학회논문지
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• 제19권4호
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• pp.25-32
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• 2014

전력선통신은 스마트그리드 기반의 서비스가 제공될 수 있는 네트워크를 위한 미래지향적 기술이다. 전력선통신 채널의 주파수 선택적 페이딩이 있는 환경에서, 직교주파수분할다중화 기술은 신뢰성 있는 통신을 제공한다. 본 논문에서는 직교주파수분할다중화 기반의 전력선통신 시스템에서 은닉학습신호를 이용한 주파수사용효율이 높은 기법을 제안한다. 은닉학습신호를 사용하면 채널 추정용 주파수를 따로 소모하지 않고도 채널 추정이 가능하고, 이는 데이터와의 간섭을 줄일 수 있는 학습신호에 할당된 파워를 이용해서 해결할 수 있다. 컴퓨터 시뮬레이션을 통해 제안한 기법이 기존의 기법들에 비해 저전압 및 중전압 송전 라인에서 높은 성취 가능한 데이터 율을 보여준다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권2호
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• pp.266-268
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• 2003

This paper makes an analysis of the ecological behaviours of 3 categories of quails, namely wild Japanese quails from the Weishan Lake Area, medium-sized domestic quails and pint-sized domestic quails. The study indicates as follows: (1) There is difference in morphological and biological habits between domestic quails and wild Japanese ones. (2) The cross-breeding between the wild and domestic quails is a cross from exclusion to affinity. (3) The behaviours of quails such as pursuit,paw and mating are selective. (4) The wild Japanese quails and domestic ones can succeed in mating and in reproducing fertilized eggs but with a low rate. (5) Evolutionary differentiation has been formed in varying degrees between the domestic quails and their wild ancestors in morphological and ecological characteristics.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.92.2-93
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• 2003

Severe soybean-sprout rot was found at the mass productive factory in 2000 and 2001 and it caused 10-20％ loss of the production. Pythium sp. was isolated almost 90％ by potato dextrose agar from rotted root and hypocotylsof the sprouts. And the pathogencity tests using test tubes with 2％ water agar and small containers (30 ${\times}$ 30 ${\times}$ 50 cm, WxLxH) cultivation were shown a similar rot on roots and hypocotyls. The fungal mycelium grew rapidly on the water agar and it prevented the seed germination. Density of the Pythium sp. in the recycled water system at the factory was periodically measured using a selective medium, corn meal agar with Pimaricin 10 mg, Rifampicin 10 mg, Ampicillin 100 mg per 1 liter in order to check the contamination of recycled water. After fitering step using 5 and 1 ml in the recycled system was applied and it was effectively controlled Pythium rot. The daily yield of sprout was stable and the occurrenceof Pythium in the recycled water was much less after filtering. The fungal isolates were identified as Pythium deliense Meurs based on various mycological characteristics on corn meal agar and sucrose-asparagine bentgrass leaf culture medium. P. deliens oogonia were spherical, smooth, 19-23 urn in diameter, and their stalk bending toward antheridia. Antheridia were straw hat-shaped, curred club-shaped, therminal or intercalary, monoclinous, occasionally diclinous, 12∼15 ${\times}$ 8∼11 um, 1(∼2) per oogonium.

• Asian-Australasian Journal of Animal Sciences
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• 제18권3호
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• pp.332-339
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• 2005

The effect of transinoculation of goat rumen liquor into sheep rumen on mimosine toxicity was studied. One adult Kutchi male goat having higher mimosine degradation capacity than sheep was gradually adapted to Leucaena leucocephala (Leucaena) leaves by feeding increasing level of eucaena leaves supplementation for 1 month. Six Bharat Merino rams (12-18 months of age) were divided into two equal groups with (group I) or without (group II) infusion of 200 ml of goat rumen liquor per animal. The mimosine degradation in groups I and II were 3.04 and 2.31; 3.90 and 3.73 mg per day per 10 ml rumen liquor respectively after 1 and 2 weeks of leucaena feeding leaves. Total rumen bacterial population in RGCA medium and in a selective medium containing iron showed an increasing trend in both groups, while the bacterial population growing in the presence of cellulose showed a decreasing trend. Animal performance data did not show any adverse effect. Results revealed that transinoculation of rumen liquor from leucaena leaves adapted goat to sheep rumen did not help to improve mimosine degradation in the sheep. The sheep transinoculated with goat rumen liquor displayed no in vivo improvements in nutrient utilization vis-a-vis mimosine metabolism.

• Journal of Microbiology and Biotechnology
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• 제7권1호
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• pp.43-48
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• 1997

Three strains capable of degrading a chlorophenol were isolated by selective enrichment from soils contaminated with industrial wastewater. A Pseudomonas solanacearum TCP114 could use 2,4,6-trichlorophenol (TCP) as sole carbon and energy source, while two strains of Pseudomonas testosteroni CPW301 and Arthrobacter ureafaciens CPR706 could use 4-CP. All isolates also grew well on phenol. The degradation of one component by a pure strain was strongly affected by the presence of other compounds in the medium, CPW301 and CPR706 entirely lost the ability to degrade 4-CP and phenol in the presence of TCP. TCP114 also lost the ability to degrade phenol when 4-CP was added to the culture medium. These restrictions on the degradability could be overcome by employing defined mixed cultures (TCP114 and one strain of 4-CP degrading strains). All three components were successfully degraded by defined mixed cultures through their cooperative activities. It was also demonstrated that defined mixed cultures could be immobilized by using calcium alginate for the semi-continuous degradation of the three component mixture. Immobilization could not only accelerate the degradation rate, but also allowed the reuse of the cell mass several times without loss of the cells' degrading capabilities.

• Journal of Microbiology
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• 제43권2호
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• pp.204-208
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• 2005

The objective of this study was to both isolate and identify non-mutans streptococci organisms (non­MSO) from dental plaques recovered on mitis-salivarius sucrose bacitracin agar (MSB) plates. The dental plaque samples, which had been collected from 63 human subjects, were diluted and plated on MSB. The bacteria growing on the MSB plates were then identified with biochemical tests, as well as with 16S rDNA cloning and sequencing techniques. Our data indicated that bacteria from 30 subjects had been recovered on the MSB plates. Among the 21 typical colonies selected from the 30 subjects, 12 colonies, derived from 10 subjects, were identified as non-MSO. These 12 colonies were determined to be Streptococcus anginosus (8 colonies), S. sanguinis (1 colony), and Pantoea agglomerans (3 colonies). These results strongly suggest that a new selective medium will be required for the reliable isolation of mutans streptococci.

• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.647-652
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• 2004

Thermophilic microorganisms capable of producing chitinase enzymes were screened from samples collected from several crater and geothermal areas. The chitinolytic microorganisms were grown in a selective medium containing colloidal chitin. The Bacillus K29-14 isolate was found to exhibit the highest chitinase and chitin deacetylase activities. When grown in a chitin-containing medium, the isolate produced extracellular chitinase after 24 h of incubation. The optimum temperature and pH for the chitinase were $55^\circ{C}$ and pH 7, respectively, while those for the chitin deacetylase were $55^\circ{C}$ and pH 8, respectively. The thermostable chitinase and chitin deacetylase also retained 80- 90% of their activity after incubation for 5 h at $70^\circ{C}$. The divalent cations $CoCl_2\;and\;NiCl_2$, increased the chitinase activity, while $ZnCl_2$, inhibited the enzyme. The chitin deacetylase was also activated by the presence of $MgCl_2$ and inhibited by $MnCl_2,\;NiCl_2,\;and\;CaCl_2$. A zymogram analysis revealed several forms of chitinase, with a 67 kDa form being the major enzyme.

• Environmental Engineering Research
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• 제10권1호
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• pp.38-44
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• 2005

Electro-thermal production of white phosphorus(WP, P4) generates substantial amount of highly toxic phossy water and sludges. Because of their high phosphorus contents and lack of reliable processing technology, large tonnages of these hazardous wastes have accumulated from current and past operations in the United States. In this study, two different methods for treatment of phosphorus sludge were investigated. These were bulk removal of WP by physical separation(froth flotation) and transformation of WP to oxyphosphorus compounds by air oxidation in the sludge medium. Kerosene, among other collectors, resulted in selective flotation of WP from the associated mineral gangue. Solvent action of kerosene occurring on the WP surface(by rendering WP particles hydrophobic) might produce the high selectivity of WP. The WP recovery in the froth was 79.3% from a sludge assaying 34.2% of WP. In the oxidation study, air gas was dispersed in the sludge medium by the rapid rotation of the impeller blades. The high level of sludge agitation intensity caused a fast completion of the oxidation reactions and it resulted in the high percentage conversion of WP to PO4-3 with PO3-3 making up almost all portion of oxyphosphorus compounds. The WP analysis on the treated sludge showed that supernatant solution and solid residue contained an average of 4.2 μg/L and 143 ppm respectively from the sludge containing about 26 g of WP. Further investigation will be required on operational factors to better understand the processes and achieve an optimum condition.