• Korean Journal of Mathematics
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• 제22권1호
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• pp.181-206
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• 2014

Let $R={\bigoplus}_{\alpha{\in}\Gamma}R_{\alpha}$ be a graded integral domain graded by an arbitrary grading torsionless monoid ${\Gamma}$, and ⋆ be a semistar operation on R. In this paper we define and study the graded integral domain analogue of ⋆-Nagata and Kronecker function rings of R with respect to ⋆. We say that R is a graded Pr$\ddot{u}$fer ⋆-multiplication domain if each nonzero finitely generated homogeneous ideal of R is ⋆$_f$-invertible. Using ⋆-Nagata and Kronecker function rings, we give several different equivalent conditions for R to be a graded Pr$\ddot{u}$fer ⋆-multiplication domain. In particular we give new characterizations for a graded integral domain, to be a $P{\upsilon}MD$.

• 한국지구과학회지
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• 제35권5호
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• pp.362-374
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• 2014

This study investigated the initial mass function (IMF) and star formation history of high-mass stars in the Small Magellanic Cloud (SMC) using a population synthesis technique. We used the photometric survey catalog of Lee (2013) as the observable quantities and compare them with those of synthetic populations based on Bayesian inference. For the IMF slope (${\Gamma}$) range of -1.1 to -3.5 with steps of 0.1, five types of star formation models were tested: 1) continuous; 2) single burst at 10 Myr; 3) single burst at 60 Myr; 4) double bursts at those epochs; and 5) a complex hybrid model. In this study, a total of 125 models were tested. Based on the model calculations, it was found that the continuous model could simulate the high-mass stars of the SMC and that its IMF slope was -1.6 which is slightly steeper than Salpeter's IMF, i.e., ${\Gamma}=-1.35$.

• 한국세라믹학회지
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• 제53권2호
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• pp.194-199
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• 2016

Presently, for the cement industry, studies that seek to reduce $CO_2$, because of the development of the plastic industry and demand for reduction of energy use, have been actively conducted among them, studies attempting to use Gamma-$C_2S({\gamma}-C_2S)$ to fix $CO_2$ have been actively conducted. The ${\gamma}-C_2S$ compound has an important function in reacting to $CO_2$ and stiffening through carbonatization in the air. The ${\gamma}-C_2S$ compound, reacting to $CO_2$ in the air, generates $CaCO_2$ within the pore structure of cement materials and densifies the pore structure this leads to an improvement of the durability and to the characteristic of resistance against neutralization. Therefore, in this experiment, in order to synthesize ${\gamma}-C_2S$, limestone sludge and waste foundry sands are used these materials are plasticized for 30 or 60 minutes at $1450^{\circ}C$, and are prevented from being cooled in the temperature range of $30{\sim}1000^{\circ}C$ when they are about to be cooled. XRD analysis and XRF analysis are used to determine the effects of this process on ${\gamma}-C_2S$ synthesization, the temperature at which a thing is plasticized, and the conditions for cooling that obtain in the plasticized clinker also, in order to confirm the $CO_2$ capture function, analysis of the major hydration products is conducted through an analysis of carbonatization depth and compressive strength, and through MIP analysis and XRD Rietveld analysis. As a result of these analyses, it is found that when ${\gamma}-C_2S$ was synthesized, the clinker that was plasticized at $1450^{\circ}C$ for one hour demonstrated the highest yield rate the sample with which the ${\gamma}-C_2S$ was mixed generated $CaCO_3$ when it reacted with $CO_2$ therefore, carbonatization depth and porosity were reduced, and the compressive strength was increased.

• 대한한방내과학회지
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• 제28권4호
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• pp.902-910
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• 2007

Objective : Peroxisome proliferator-activated receptor (PPAR)-gamma, a transcription factor in adipocyte differentiation, has important effects on insulin sensitivity, atherosclerosis, endothelial cell function and inflammation. Through these effects, PPAR-gamma2 might be involved with type 2 diabetes and vascular disease, including diabetic complications. Recently, it has been reported that the C161T polymorphism in the exon 6 of PPAR-gamma is associated with type 2 diabetes interacting with uncoupling protein 2 (UCP2) gene, and is associated with acute myocardial infarction. We studied the association of this polymorphism with type 2 diabetes and its complications, such as retinopathy, ischemic stroke, nephropathy and neuropathy in Korean non-diabetic and type 2 diabetic populations. Methods : Three hundred and thirty eight type 2 diabetic patients (retinopathy: 64, ischemic stroke: 67, nephropathy: 39 and neuropathy: 76) and 152 healthy matched control subjects were evaluated. The PPAR-gamma C161T polymorphism was analyzed by PCR-RFLP. Results : PPAR-gamma C161T genotype and allele frequency did not show significant differences between type 2 diabetic patients and healthy controls (T allele: 17.0 vs. 14.5, OR= 1.21, P=0.3188). In the analysis for diabetic complications, T allele in diabetic nephropathy was significantly higher than controls (P=0.0358). T allele in the ischemic stroke patients was also higher than healthy controls, although it had no significance (P=0.1375). Conclusions : These results suggest that the C161T polymorphism of the PPAR-gamma gene might be associated with diabetic nephropathy in type 2 diabetes.

• 한국컴퓨터정보학회논문지
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• 제19권7호
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• pp.71-76
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• 2014

대표적인 공개키 암호방식인 RSA에 사용되는 합성수 n=pq의 큰자리 소수 p,q를 소인수분해하여 구하는 것은 사실상 불가능하다. 공개키 e와 합성수 n은 알고 개인키 d를 모를 때, ${\phi}(n)=(p-1)(q-1)=n+1-(p+q)$을 구하여 $d=e^{-1}(mod{\phi}(n))$의 역함수로 개인키 d를 해독할수 있다. 따라서 ${\phi}(n)$을 알기위해 n으로부터 p,q를 구하는 수학적 난제인 소인수분해법을 적용하고 있다. 소인수분해법에는 n/p=q의 나눗셈 시행법보다는 $a^2{\equiv}b^2(mod\;n)$, a=(p+q)/2,b=(q-p)/2의 제곱합동법이 일반적으로 적용되고 있다. 그러나 다양한 제곱합동법이 존재함에도 불구하고 아직까지도 많은 RSA 수들이 해독되지 않고 있다. 본 논문은 ${\phi}(n)$을 직접 구하는 알고리즘을 제안하였다. 제안된 알고리즘은 $2^j{\equiv}{\beta}_j(mod\;n)$, $2^{{\gamma}-1}$ < n < $2^{\gamma}$, $j={\gamma}-1,{\gamma},{\gamma}+1$에 대해 $2^k{\beta}_j{\equiv}2^i(mod\;n)$, $0{\leq}i{\leq}{\gamma}-1$, $k=1,2,{\ldots}$ 또는 $2^k{\beta}_j=2{\beta}_j$로 ${\phi}(n)$을 구하였다. 제안된 알고리즘은 $n-10{\lfloor}{\sqrt{n}}{\rfloor}$ < ${\phi}(n){\leq}n-2{\lfloor}{\sqrt{n}}{\rfloor}$의 임의의 위치에 존재하는 ${\phi}(n)$도 약 2배 차이의 수행횟수로 찾을 수 있었다.

• Tuberculosis and Respiratory Diseases
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• 제56권6호
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• pp.619-627
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• 2004

연구배경 : 특발성 폐섬유화증의 치료로서 항섬유화제제인 IFN-${\gamma}1b$로 단기간 치료 받은 환자들의 치료반응 및 부작용을 보고자 하였다. 방 법 : IFN-${\gamma}1b$ (200만 IU씩 주 3회 피하주사)로 치료받은 특발성 폐섬유화증 환자 27명을 대상으로 후향적 연구를 하였다. 이 중 6개월 이상 IFN-${\gamma}1b$ 치료를 받은 17명의 치료반응을 평가하여 cortico-steroids와 cyclophosphamide로 치료 받은 26명의 치료반응과 비교하였다. 결 과 : 1) 총 27명의 연령은 59(44-74)세 였고 남자가 19명(70%) 이었다. 2) 사망 및 진행을 보인 악화군(5명)은 안정군(12명)에 비해 치료 전 FVC(55% vs. 71%, p=0.019)와 DLco(50% vs. 77%, p=0.014)가 좋지 않았고, 치료전 동맥혈 산소분압(69mmHg vs. 91mmHg, p=0.001)도 낮았다. 3) corticosteroids와 cyclophosphamide로 치료 받은 26명과 IFN-${\gamma}1b$로 치료 받은 17명의 6개월 후 치료반응은 서로 차이가 없었다(p=0.73). 4) 부작용은 총 12명(44%)에서 발생하였고 이 중 5명은 심각한 약제 부작용으로 치료를 중단하였고 1명은 급성호흡곤란증후군으로 사망하였다. 결 론 : IFN-${\gamma}1b$의 단기간 치료는 폐기능이 좋지 않거나 진행된 상태의 특발성 폐섬유화증 환자의 치료로는 바람직하지 않으며 치명적인 부작용이 발생할 수 있으므로 조심스럽게 사용하여야 한다고 생각한다.

• 대한수학회논문집
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• 제29권2호
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• pp.239-255
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• 2014

We develop a set of identities for Euler type sums. In particular we investigate products of shifted harmonic numbers of order two and reciprocal binomial coefficients.

• 대한수학회논문집
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• 제28권3호
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• pp.527-534
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• 2013

We first aim at proving an interesting easily derivable summation formula. Then it is easily seen that this formula immediately yields a hypergeometric summation theorem recently added to the literature by Qureshi et al. Moreover we apply the main formulas to present some interesting summation formulas, whose special cases are also seen to yield the earlier known results.

• Journal of Applied Biological Chemistry
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• 제55권1호
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• pp.1-5
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• 2012

Recently, we reported that Jeju ground water contains vanadium components and exerts antioxidant effects in vitro and in vivo via the scavenging of reactive oxygen species and enhancement of antioxidant enzyme activities. In the present study, the antioxidant actions of Jeju ground water were compared with those of tap water against gamma-ray radiation in mice. C57BL/6 mice were irradiated with gamma-ray at a dose rate of 2 Gy. The mice were then given tap water or Jeju ground water for 90 days. Jeju ground water compared with tap water enhanced the activities and levels of superoxide dismutase, catalase, and glutathione peroxidase in irradiated liver tissues. Jeju ground water also enhanced the levels of intracellular reduced glutathione, which is vital for normal liver function and repair. These results suggest that vanadium-containing Jeju ground water can safeguard against the harmful actions of gamma-ray radiation through the support of hepatic antioxidant processes.

• Molecules and Cells
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• 제40권1호
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• pp.73-81
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• 2017

The ${\gamma}$-secretase complex represents an evolutionarily conserved family of transmembrane aspartyl proteases that cleave numerous type-I membrane proteins, including the ${\beta}$-amyloid precursor protein (APP) and the receptor Notch. All known rare mutations in APP and the ${\gamma}$-secretase catalytic component, presenilin, which lead to increased amyloid ${\beta}$-peptide production, are responsible for early-onset familial Alzheimer's disease. ${\beta}$-amyloid protein precursor-like (APPL) is the Drosophila ortholog of human APP. Here, we created Notch- and APPL-based Drosophila reporter systems for in vivo monitoring of ${\gamma}$-secretase activity. Ectopic expression of the Notch- and APPL-based chimeric reporters in wings results in vein truncation phenotypes. Reporter-mediated vein truncation phenotypes are enhanced by the Notch gain-of-function allele and suppressed by RNAi-mediated knockdown of presenilin. Furthermore, we find that apoptosis partly contributes to the vein truncation phenotypes of the APPL-based reporter, but not to the vein truncation phenotypes of the Notch-based reporter. Taken together, these results suggest that both in vivo reporter systems provide a powerful genetic tool to identify genes that modulate ${\gamma}$-secretase activity and/or APPL metabolism.