• 한국세라믹학회지
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• 제20권3호
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• pp.236-242
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• 1983

The purpose of present study is to find the structures physical properties and their inter-relations in the system of (60-x) PbO.xMO.$40B_2O_3$ glasses where MO represents for ZnO and CdO. The experiments such as differential thermal analysis infrared spectral analysis X-ray diffraction analysis density and thermal expansion measurements have been done. From infrared spectral analysis the structural units of glasses and the corresponding crystallized glasses were com-posed of $BO_3$ triangles and $BO_4$ tetrahedra. These basic units found in $PbO-B_2O_3$ binary glass system did not charge even though the divalent metallic oxides were substituted for PbO. The structures of these ternary glasses were more coalescenced than $PbO-B_2O_3$ binary glass system. This fact was supported bydecrease in thermal expansion coeffici-ent and molar volume with substitution of divalent metallic oxide for PbO. Crystalline phases obtained from the heat treatment of the $PbO-ZnO-B_2O_3$ glasses were 4PbO.2ZnO.$5B_2O_3$ PbO.2ZnO.$B_2O_3$ and unknown phases.

• 한국응용과학기술학회지
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• 제39권4호
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• pp.535-541
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• 2022

The radical reaction position was calculated by varying the calculation level for ACEL and ANT, which are detected with the highest frequency and concentration in PAHs pollution sites. The results of each calculation level were compared and evaluated with the existing literature. HF, B3LYP, B3LYP-D, and MP2 were used as the method for each level used for calculation. Except for HF, the MK charge by B3LYP, B3LYP-D, and MP2 was consistent with the experimental results. It was found that the dispersion effect was negligible in the calculation of ACEL and ANT because the calculation results by the B3LYP and B3LYP-D methods were the same. In particular, it was found that the MK charge calculation result by MP2 agrees well with the product/PAH ratio obtained as a result of the experiment. Considering the calculation cost, it would be preferable to use B3LYP to predict the radical reaction site of ACEL and ANT. However, considering the product/PAH ratio, it takes more time to calculate, but it is judged that it is better to use the MP2.

• 약학회지
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• 제49권4호
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• pp.299-305
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• 2005

Structure-activity relationship studies of allylamine type of antimycotics were carried out to evaluate the effect of naphthyl and methyl portion of naftifine. Compounds with 3,4-difluorophenyl (2a-5a), 4-hydroxyphenyl (2b-5b), 3-nitro­phenyl (2c-5c), 4-chlorobenzothiazoly (2d-5d) and 5-methylfurfural (2e-5e) instead of naphthyl group, and with hydrogen (3a-3e), methyl (4a-4e) and ethyl (5a-5e) in the place of methyl in naftifine were synthesized and tested for their in vitro anti-fungal activities against five different fungi. Fourteen compounds (3a, 4a, 5a, 3b, 4b, 5b, 3c, 4c, 5c, 3d, 4d, 3e, 4e and 5e) showed significant anti-fungal activities against T. mentagrophytes. (E)-N-(3-Phenyl-2-propenyl)-3,4-difluoro-ben­zenemethaneamine(3a), (E)_N_(3_phenyl_2_propenyl)_4_hydroxy_benzenemethaneamine(3b) and (E)-N-ethyl-N-(3-phenyl­2-propenyl)-3-nitro-benzenemethaneamine (5c) displayed moderate anti-fungal activities against all five different fungi.

• 한국환경과학회지
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• 제7권5호
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• pp.633-638
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• 1998

To determine whether the enhanced UV-B causes oxidative stress, and to test the relationship between plant growth response and biochemical defense response to UV-B, two soybean plants, Keunolkong, a highly UV-B susceptible cultivar, and Danyeubkong, a less UV-B susceptible cultivar, were subjected to the enhanced UV-B [daily dose : 0.06 (control) and 11.32 (enhanced UV-B) kJ $m^{-2}$ ; $UV-B_{BE}$] for 3 weeks. Contents of malondialdehyde and total carotenold were increased in Keunolkong compared with Danyeubkong by UV-B. In control plants, ascorbate level of Danyeubkong was 3 times higher than that of Keunolkong. The ratio of dehydroascorbate/ascorbate was highly increased in Keunolkong by UV-B . The activities of antioxidative enzyme such as superoxide dismutase, ascorbate peroxidase, monodehydroascorbate reductase and glutathione reductase were increased in both cultivars by UV-B. This results indicate that enhanced UV-B caused oxidative stress in both two cultivars, especially in Keunolkong. Susceptibility of two soybean cultivars to UV-B is closely related to the levels of antioxidants such as carotenoid and ascorbate.

• Journal of Korean Neurosurgical Society
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• 제29권6호
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• pp.725-730
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• 2000

Purpose : The subcellular localization of E1B-19k has been known cytosol or nuclear membrane by immunohistochemical staining and could dimerize with Bax to regulate cell death also known by the in-vitro immunoprecipitation. We planed to confirm this dimerization of E1B-19k with Bax in vivo in Cos-7 cells by using green fluorescent protein. Material and Method : We cloned E1B-19k and Bax into C3-EGFP. C3-EGFP-E1B-19k, C3-EGFP-Bax, and C3-EGFP-E1B-19k and pcDNA3-Bax were transfected into Cos-7 cells. We explored location of E1B-19k and Bax, and confirmed its dimerization with Bax in transfected living healthy Cos-7 cells by following green fluorescent protein of E1B-19k on the confocal microscope. Results : E1B-19k was located diffusely in cytoplasm and in nucleus but not in mitochondria. It prevented cell death from the apoptosis by staurosporine but its location was not changed. GFP-E1B-19k is not changed its intracellular location with Bax even with staurosporine. Conclusion : These results support that E1B-19k does not localize in mitochondria nor dimerize with Bax even with staurosporine. We could anticipate E1B-19k prevent cell death via the other dimerizing partner or pathways.

• Geomechanics and Engineering
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• 제14권2호
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• pp.141-149
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• 2018

In this paper, the creep behavior of bolted rock was analyzed by using the unconfined creep tests and the numerical results. Based on the test results, the Bolted Burgers creep model (B-B model) was proposed to clarify the creep mechanism of rock mass due to rock bolts. As to the simulation of the creep behaviour of bolted rock, a new user-defined incremental iterative format of the B-B model was established and the open-source $FLAC^{3D}$ code was written by using the object-oriented language (C++). To check the reliability of the present B-B creep constitutive model program, a numerical model of a tunnel with buried depth of 1000 m was established to analyze the creep response of the tunnel with the B-B model support, the non-support and the bolt element support. The simulation results show that the present B-B model is consistent with the calculated results of the inherent bolt element in $FLAC^{3D}$, and the convergence deformation can be more effectively controlled when the proposed B-B model is used in the $FLAC^{3D}$ software. The big advantage of the present B-B creep model secondarily developed in the $FLAC^{3D}$ software is the high computational efficiency.

• 미생물학회지
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• 제52권3호
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• pp.254-259
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• 2016

시드로포어인 2, 3-dihydroxybenzoic acid (DHB)를 생산하는 Acinetobacter sp. B-W의 플라스미드를 분석한 결과, 20 kb 크기의 플라스미드를 함유하였다. 배양 온도 $43^{\circ}C$ 가 플라스미드가 제거된 돌연변이체 생산에 효과적이었다. 이 돌연변이체는 2,3-DHB 생산 능력을 소실하였으며, chrome azurol S (CAS) 아가 배지에서 시드로포어 생산이 검출되지 않았다. 포도당과 황산 망간을 함유한 배지에서 $28^{\circ}C$로 3일간 배양한 B-W 원 균주와 돌연변이체의 배양 상등액의 pH는 각각 4.5와 8.5로 나타났다. 돌연변이체에서는 ampicillin, actinomycin D, bacitracin, lincomycin과 vancomycin 같은 항생제에 대한 저항성이 사라졌으며, 이러한 항생제에 대한 최소 억제 농도(MIC)가 급격하게 감소하였다. B-W 균주에서 분리한 플라스미드로 대장균을 형질전환시킨 결과, 원 균주와 같은 크기의 플라스미드가 이 형질전환 대장균에서 발견되었다. 플라스미드가 제거된 돌연변이체에서는 플라스미드가 발견되지 않았다. 20 kb 크기의 플라스미드에 2,3-DHB 생산 유전자와 여러 항생제 저항성 유전자가 자리잡고 있는 것으로 추정된다.

• IMMUNE NETWORK
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• 제2권2호
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• pp.86-90
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• 2002

Background: Host genetic polymorphisms in the HIV-1 co-receptor CCR5 and CCR2b and SDF-1, ligand for co-receptor CXCR4, have been known to be associated with the resistance of HIV infection and/or the delayed disease progression in HIV-infected patients. Methods: We examined the frequencies of SDF1-3'A and CCR2b-64I alleles of 354 Koreans including 100 HIV-uninfected persons, 13 discordant spouses of HIV-infected persons, and 241 HIV-infected persons. The genotyping assays of SDF1 and CCR2b genes were carried out by polymerase chain reaction-restriction fragment length polymorphism. Results: The frequencies of CCR2b-64I and SDF1-3'A alleles in Koreans were very high compared with Caucasians and blacks. Observed frequencies of CCR2b-64I and SDF1-3'A allelic variants were 25.1% and 28.7%, respectively. The frequency of the CCR2b-64I allele in Koreans was 2~4 times higher than those of other ethnic groups with the exception of Asian. The frequencies of CCR2b-64I and SDF1-3'A genotypes did not show the significant difference between HIV-infected and uninfected Koreans. However, the prevalence of CCR2b-64I genotype of the LTNP group was about two times higher than that of the remainder group (P< 0.05). Four (45%) out of 9 LTNPs (long-term nonprogressors) showed having the SDF1-3'A allele and 7 (78%) out of 9 LTNPs carried the CCR2b-64I allele. 3 (33%) out of 9 LTNPs had both SDF1-3'A and CCR2b-64I alleles. But none of 5 RPs (rapid progressors) appeared to have both SDF1-3'A and CCR2b-64I alleles. Conclusion: The different genetic backgrounds in study populations may affect the disease progression and the AIDS epidemic in each country. Further studies need to define whether high frequencies of CCR2b-64I and SDF1-3'A allelic variants may affect the HIV disease progression.

• Journal of Acupuncture Research
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• 제29권1호
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• pp.37-45
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• 2012

목적 : 최근 NF-${\kappa}B$와 STAT3의 활성억제와 관련된 항암제 연구가 주목받고 있으며, 본 연구는 사독(蛇毒)이 세포자멸사 관련 단백질의 발현 조절을 통하여 세포자멸사를 유도하고, NF-${\kappa}B$와 STAT3의 활성억제를 유도하여 난소암 PA-1 세포의 성장을 억제하는지를 확인하고, 해당 기전을 살펴보고자 하였다. 방법 : 사독을 처리한 후 난소암 PA-1 세포의 세포자멸사의 관찰에는 DAPI, TUNEL staining assay를 시행하였고, 세포자멸사 조절단백질 및 NF-${\kappa}B$, STAT3의 활성 변동 관찰에는 western blot analysis를 시행하였다. 결과 : 1. 사독을 처리한 후 난소암 PA-1 세포에서 세포자멸사가 유도되어 암세포성장이 억제되었다. 2. 사독을 처리한 후 세포자멸사 관련 단백질 중 세포자멸사 촉진 단백질인 cleaved caspase-3, Bax의 발현은 증가되었고, 세포자멸사 억제 단백질인 Bcl-2의 발현은 감소되었다. 3. 사독을 처리한 후 난소암 PA-1 세포의 NF-${\kappa}B$와 STAT3 발현은 감소되었고, 각각의 길항제인 salicylic acid와 stattic 처리 후 NF-${\kappa}B$와 STAT3 발현은 더욱 감소되었다. 결론 : 사독은 난소암 세포의 세포자멸사 유발과, NF-${\kappa}B$와 STAT3의 활성억제를 통해 치료 효율이 높고, 내성이 적은 난소암 치료제의 개발에 도움이 될 것으로 기대된다.

• 미생물학회지
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• 제37권2호
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• pp.158-163
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• 2001

Avermectin B1a의 생산성 향상을 위하여 무기인의 영향을 조사하고, 주요 유기질소원의 최적농도를 response surface methodology를 적용하여 구하였다. 1.5 g/ι의 농도로 무기인을 아버멕틴 생산배지에 첨가하였을 때 B1b 성분의 구성비가 5.8%에서 3%로 감소하였으며 B1a 생성은 영향을 받지 않았다. 배지의 주요성분인 대두분, 면실분, 효모추출물 중 아버멕틴 생성에 가장 큰 영향을 끼치는 유기질소원은 대두분이었다. 실험실 규모 발효조에서 Streptomyces avermifilis YA99-40의 유가식 회분배양에 의해 아버멕틴 생산성을 회분배양에 비해 44.8% 증가시킬 수 있었다. 발효조 배양시작 후 136, 206 시간에 각각 30, 20 g/ι의 당을 추가하는 유가식 회분배양을 실시하였을 때 B1a 성분의 최대 생산성은 회분배양 대비 86.3% 증가하였으며 생성된 총 아버멕틴 중 B1a의 구성비율도 화분배양에 비해 38%에서 45%로 향상되었다. 이 같은 결과는 산업적인 규모로 아버멕틴의 생산성을 향상시키는데 유용하게 적용시킬 수 있다.