• Journal of Welding and Joining
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• 제3권1호
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• pp.32-39
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• 1985

Fatigue lives of C.T. specimens containing the holes or the holes filled with other materials are investiated by experimental and analytical methods. The results of the study are as follows; 1) The fatigue lives are in the order of E'/E > 1, E'/E = 1, and E'/E < 1, where E' is the Young's modulus of other materials filling holes and E is that of matrix. 2) The fatigue life of E'/E = 0 is shortest than thost of E'/E > 1, E'/E = 1 and E'/E < 1. 3) The fatigue life of C.T. specimen containing the holes filled with other materials is shorter than that of matrix without holes. 4) Because of the stress concentration around the bonding boundary, crack initiates from the lower left on the boundary and propagates toward the upper right along the boundary.

• 대한화학회지
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• 제18권3호
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• pp.202-209
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• 1974

물 아닌 용매 아세토니트릴에서 구리와 카드뮴의 2,2´-비피리딘(bipy.)과 에틸렌디아민(en.) 착물의 성질의 직류와 교류폴라로그래프로 조사한 결과 각 착물의 전극과정은 아래와 같이 생각된다. $Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}\risingdotseq+0.1V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.43V}}\;Cu(Hg)$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}}\;Cu(I)-en.\;complex\;{times}\;{\longrightarrow^{e^-}_{E_{1/2}=-0.56V}}\;Cu(Hg)$$Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.57V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{2e^-}_{E_{1/2}=-0.97V}}\;Cd(I)-bipy\;complex$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=+0.05V}\;Cu(I)-en.\;complex{\longrightarrow^{e^-}_{E_{1/2}=-0.92V}}\;Cu(Hg)$이상의 모든 파는 학산에만 의존한다. 또 Cu(Ⅰ)-bipy. 착물의 리간드의 수는 2이며, 착물해리상수 $K_d=(1.5{\pm}0.1){\times}10^{-7}$이었다.

• Toxicological Research
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• 제19권3호
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• pp.235-240
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• 2003

The modification of CYP2E1 activity is of considerable interest because of its role in the metabolic activation of a variety of toxic chemicals. In the present studies, the time-course of changes in human CYP2E1 activities was determined after treatment with ethanol, glycerol, 4-methylpyrazole or isoniazid using intact HepG2 cells transfected by human CYP2E1. Hydroxylation of chlorzoxazone was chosen for the measurement of CYP2E1 activity. CYP2E1 protein levels were increased upon cultivation of cells in the presence of ethanol, glycerol, 4-methylpyrazole or isoniazid for 24 hr. After 24 hr cultivation, ethanol or glycerol increased CYP2E1 activities, whereas 4-methylpyrazole or isoniazid inhibited. This different effect of the chemical inducers on CYP2E1 activi-ties persisted to subsequent 24 hr. Competitive inhibition study suggested that 4-methylpyrazole or isoniazid has stronger binding affinity to CYP2E1 than ethanol or glycerol. These results demonstrate that different binding affinity of the chemical inducers to the active site of CYP2E1 plays important role in determining real CYP2E1 activity in intact cells after treatment with the chemical inducers. Present study would be helpful in precise understanding of human CYP2E1-mediated toxicity.

• Toxicological Research
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• 제18권4호
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• pp.325-330
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• 2002

In this study, the biochemical role of genetic polymorphism in modulating urinary excretion of benzene metabolite as phenol level has been investigated in 90 workers exposed to benzene in the petroleum refinery plant of Korea. The mean concentration of volatile benzene in the refinery environment was 0.042 mg/㎥ (SD, 0.069) and that of urinary phenol was 7.42 mg/g creatinine (SD, 11.3). The frequencies of CYP2E1 genotypes, namely CYP2E1$^*1$/$^*1$, CYP2E1$^*1$/$^*2$ and CYP2E1$^*2$/$^*2$ were 2.2% (2 subjects), 6.7% (G subjects) and 91.1% (85 subjects), respectively, and allele frequencies for CYP2E1$^*1$ and CYP2E1$^*2$ were 0.06 and 0.94. The airborne benzene concentration was significantly related to the concentration of phenol in urine (r = 0.640, p < 0.01). The urinary phenol level was significantly correlated with CYP2E1$^*2$/$^*2$ (r = 0.590, p < 0.05). The various biological (i.e. age and liver function parameters) or lifestyle factors (i.e. medication, smoking, alcohol and coffee intake), also taken into account as potential confounders, did not influence the correlation found. These results suggested that CYP2E1 genotypes might play an important role in the metabolism of benzene.

• 생명과학회지
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• 제24권8호
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• pp.910-914
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• 2014

본 연구는 현행 한우확인시험법에 이용되는 Microsatellite (MS)와 소의 유전형질 중 품종 판별에 주로 이용되는 Melanocortin Receptor 1 (MC1R) 유전자상의 Single Nucleotide Polymorphism (SNP)를 분석하여 설계한 Primer를 Multiplex PCR을 활용하여 소의 품종을 판별하였다. MC1R 유전자형은 $E^D$, $E^+$, e형의 3Type으로 나뉘며 $E^D/E^D$, $E^D/E^+$, $E^D/e$, $E^+/E^+$, $E^+/e$, e/e의 6가지 유전자형을 가진다. $E^D$유전자형은 외래종이 지닌 유전자형으로 $E^D/E^D$, $E^D/E^+$, $E^D/e$이 이에 속하며, e유전자형은 한우가 지닌 유전자형으로 e/e의 유전자형을 가진다. 흑한우의 경우 $E^D$, $E^+$, e의 모든 유전자형을 가지고 있으나 이는 교잡에 의해 나타난 것으로 보이며 $E^+$유전자형이 흑한우 고유의 유전자형으로 추정되어 본 연구에서는 이에 따라 $E^+/E^+$, $E^+/e$의 유전자형을 흑한우로 분류하였다. 그러나 $E^D$, $E^+$의 경우 단순 PCR기법만으로는 그 판별에 어려움이 있어, MS Maker를 활용한 다형성 분석을 통해 흑한우와 수입우를 판별할 수 있는 새로운 Primer를 설계하였으며, 이를 통해 소의 품종을 판별하였다.

• Journal of Microbiology and Biotechnology
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• 제22권2호
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• pp.176-183
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• 2012

Eukaryotic translation termination is governed by eRF1 and eRF3. eRF1 recognizes the stop codons and then hydrolyzes peptidyl-tRNA. eRF3, which facilitates the termination process, belongs to the GTPase superfamily. In this study, the effect of the MC domain of eRF1a (eRF1aMC) on the GTPase activity of eRF3 was analyzed using fluorescence spectra and high-performance liquid chromatography. The results indicated eRF1aMC promotes the GTPase activity of eRF3, which is similar to the role of eRF1a. Furthermore, the increased affinity of eRF3 for GTP induced by eRF1aMC was dependent on the concentration of $Mg^{2+}$. Changes in the secondary structure of eRF3C after binding GTP/GDP were detected by CD spectroscopy. The results revealed changes of conformation during formation of the eRF3C GTP complex that were detected in the presence of eRF1a or eRF1aMC. The conformations of the eRF3C eRF1a GTP and eRF3C eRF1aMC GTP complexes were further altered upon the addition of $Mg^{2+}$. By contrast, there was no change in the conformation of GTP bound to free eRF3C or the eRF3C eRF1aN complex. These results suggest that alterations in the conformation of GTP bound to eRF3 is dependent on eRF1a and $Mg^{2+}$, whereas the MC domain of eRF1a is responsible for the change in the conformation of GTP bound to eRF3 in Euplotes octocarinatus.

• 대한수학회지
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• 제59권1호
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• pp.71-85
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• 2022

In [4], the authors showed that if an h-vector (h₀, h₁, …, h_e) with h₁ = 4e - 4 and h_i ≤ h₁ is a Gorenstein sequence, then h₁ = h_i for every 1 ≤ i ≤ e - 1 and e ≥ 6. In th_is paper, we show that if an h-vector (h₀, h₁, …, h_e) with h₁ = 4e - 4, h₂ = 4e - 3, and h_i ≤ h₂ is a Gorenstein sequence, then h₂ = h_i for every 2 ≤ i ≤ e - 2 and e ≥ 7. We also propose an open question that if an h-vector (h₀, h₁, …, h_e) with h₁ = 4e - 4, 4e - 3 < h₂ ≤ (h₁)₍₁₎|⁺¹₊₁, and h₂ ≤ h_i is a Gorenstein sequence, then h₂ = h_i for every 2 ≤ i ≤ e - 2 and e ≥ 6.

• Molecules and Cells
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• 제24권3호
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• pp.445-451
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• 2007

Translation initiation factor 4E (eIF4E) is a key regulator of protein synthesis. Abnormal regulation of eIF4E is closely linked to oncogenic transformation. Several regulatory mechanisms affecting eIF4E are discussed, including transcriptional regulation, phosphorylation and binding of an inhibitor protein. However it is not clear how the level of eIF4E protein is regulated under basal conditions. Here we demonstrate that Diap1 (Drosophila Inhibitor of Apoptosis Protein), a cell death inhibitor, binds directly to eIF4E and poly-ubiquitinates it via its E3 ligase activity, promoting its proteasome-dependent degradation. Expression of Diap1 caused a reduction of Cyclin D1 protein level and inhibited the growth stimulation induced by overexpression of eIF4E. Taken together, our results suggest that the level of eIF4E protein is regulated by Diap1, and that IAPs may play a role in cap-dependent translation by regulating the level of eIF4E protein.

• 한국식품과학회지
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• 제33권6호
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• pp.728-736
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• 2001

본 연구에서는 우리의 전통한과인 유과의 저장성을 향상시키기 위하여 저장 중 저장조건에 따른 품질변화를 측정하고자 하였다. 유과를 상온에서 저장하면서 색을 측정한 결과 백색도(L)의 경우 저장기간 동안 전반적으로 감소하였고, 적색도(a)의 경우 E1EA 처리구는 감소하였고, 황색도(b)의 경우 저장초기부터 서서히 증가하였다. 텍스쳐에 있어서 상관성을 보이는 경도와 씹힘성의 경우 전반적으로 감소하는 경향이었으나 E2A, E2EA 처리구는 저장기간이 길어질수록 감소하였고 E1A 및 E1EA 처리구는 감소하다가 증가하는 경향이었다. 산가는 E2A 처리구는 12주 저장까지, E1A와 E1EA는 10주 저장까지 한과류에 대한 기준치인 2.0 이하로 측정되었다. 저장 중 산패의 지표인 과산화물가는 E1A, E2A 처리구는 저장 12주까지 기준치인 40이하로 측정되었으며. E2EA의 경우 단지 포장재만으로도 10주까지 34.65로 아주 낮은 값을 보여주었다. Electronic nose를 이용하여 대조구와 처리구간의 향기특성 패턴을 분석한 결과 6주 저장까지는 포장재질에 따른 향기특성의 변화가 가장 적은 것으로 나타났는데, 이는 탈산소재의 유무와 관계없이 포장재의 영향이 큰 것으로 생각된다. 관능특성에서 탈산소재 처리에 의한 것은 E2A 및 E2EA 처리구가 높게 평가되었는데 이는 포장재질의 영향으로 보이며, 포장재에 탈산소재를 첨가한 E2A가 가장 적합한 것으로 나타났다. 관능검사 결과와 전자코에 의한 향기성분 결과는 매우 유사한 경향을 나타내었다.

• 한국동물위생학회지
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• 제20권1호
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• pp.11-18
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• 1997

Characteristics, pathogenicity and control of the causative organisms isolated front diseased cultured flounder, Paralichthys olivaceus were studied. The causative organisms were identified as E tarda by biochemical and biophysical characteristics. Also, it strains were named as E tarda KBF-1 and E tarda KMF-1, and optimal pH of E tarda KBF-1 and E tarda KMF-1 were 8.0, and optimal concentration of NaCl. E tarda KBF-1 was 0% and E tarda KMF-1 was 1%. In the pathogenicity test, 0~10 of the flounders of artificially infected group(E tarda KBF-1) with $1.0{\times}10^7$ cfu/fish were died within 60 hrs, but 0~9 flounders infected group with 41.0{\times}10^6$ cfu/fish were died within 60 hrs. Also, 0~10 flounders infected group(E tarda KMF-1) with $1.0{\times}10^7$ cfu/fish were died within 36 hrs, while 0~7 flounders infected with $1.0{\times}10^6$ cfu/fish were died within 60 hrs. Drug sensitivity of E tarda KBF-1 strain was resistant to AM, CF and N, and intermediate to E, K and S, and sensitivity to C, G, SxT and FF. But E tarda KMF-1 strain was resistant to CF, E and V, and intermediate to AM, C, N and SxT, and sensitivity to GM and FF.