• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1267-1274
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• 2004

Colostrum contains various kinds of cytokines including TGF-$\beta$ that has potent regulatory effects on cells of the immune system. We compared the levels of TGF-$\beta$1 and TGF-$\beta$2 in bovine and human colostrum. Based on the isoform-specific ELISA, bovine colostrum collected on day 1 post-delivery retained $53.71{\pm}29.55\;ng/ml$ of TGF-$\beta$1 and $40.41{\pm}21.78\;{\mu}g/ml$ of TGF-$\beta$2 (n=4), while in human, $381.45{\pm}158.24\;ng/ml$ of TGF-$\beta$1 and $41.47{\pm}9.63\;ng/ml$ of TGF-$\beta$2 (n=5). Thus, dominant TGF-$\beta$ isoforms were completely opposite between human and bovine colostrum samples. The concentrations of both isoforms declined as lactation proceeded. Biological activities of the colostrum samples were determined using an MV1LU cell line. Consistent with the result from the immunoassay, TGF-$\beta$1 in human and TGF-$\beta$2 in bovine colostrum were responsible for the anti proliferative activity against MV1LU cells. Furthermore, bovine colostrum increased IgA secretion by LPS-stimulated mesenteric lymph node (MLN) cells, and this effect was abrogated by either anti­TGF-$\beta$2 antibody or combined anti-TGF-$\beta$1/$\beta$2 antibody, but not by anti- TGF-$\beta$1 antibody alone. Similarly, TGF-$\beta$2 in bovine colostrum enhanced the Ig germ line (GL) promoter activity, which is the earliest event toward IgA isotype switching. Taken together, these results suggest that TGF-$\beta$ isoforms, differentially expressed in human and bovine colostrum, may promote IgA isotype production in the neonatal intestine.

• Analytical Science and Technology
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• v.18 no.3
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• pp.241-249
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• 2005

In this study, instrumental neutron activation analysis was used to measure the concentrations of about 30 trace elements in airborne particulate (PM2.5) samples at urban area of Daejeon city located in the southwestern region of Korea. An inspection of the measurement data indicates that the distribution patterns of trace elements could clearly distinguish the elements with their concentrations ranging over five orders of magnitude. The mean values for Lu and Dy were found to be the lowest at values of 0.01 and $0.04ng/m^3$, while those for K and Fe showed the highest value of 671 and $653ng/m^3$, respectively. The results of correlation analysis showed that PM2.5 concentrations can exhibit much more enhanced correlations with the elements of earth crustal components. The results of factor analysis further indicated that there are no more than six factors with statistical significance, which may exert dominant roles in regulating the elemental concentration levels in the study area. Enrichment factor analysis supports explicit interpretation of results found by this factor analysis.

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1863-1866
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• 2007

• Proceedings of the Korean Society for Language and Information Conference
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• 2002.02a
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• pp.455-464
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• 2002

No Abstract(See Full Text)

• Wind and Structures
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• v.17 no.2
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• pp.123-133
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• 2013

Pressure field and velocity profiles in a thunderstorm downburst are significantly different from that of an atmospheric boundary layer wind. A model of the pressure field in a downburst is presented in accordance with the experimental and numerical results. Large eddy simulation method is employed to investigate transient pressure field on impingement ground of a downburst. In addition, velocity profiles of the downburst are studied, and good agreement is achieved between the present results and the data obtained from empirical models.

• Bulletin of the Korean Mathematical Society
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• v.50 no.5
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• pp.1441-1450
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• 2013

In this paper, we consider two-component Bose-Einstein condensates with an internal atomic Josephson junction in the general case, i.e., 0 < p < $\frac{2}{(d-2)^+}$. We prove existence and uniqueness results for the ground states, and obtain some properties of the ground states with large parameters.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.11a
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• pp.163-164
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• 2004

• Journal of the Korean Mathematical Society
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• v.51 no.2
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• pp.325-344
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• 2014

The aim of this paper is to generalize the theory of Hopf-Ore extension on Hopf algebras to Hopf group coalgebras. First the concept of Hopf-Ore extension of Hopf group coalgebra is introduced. Then we will give the necessary and sufficient condition for the Ore extensions to become a Hopf group coalgebra, and certain isomorphism between Ore extensions of Hopf group coalgebras are discussed.

• The Korean Journal of Rheology
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• v.7 no.2
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• pp.101-109
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• 1995

아주작은 Reynolds수 조건하의 나선형 미세입자가 갖는 저항 및 이동계수를 계산하 는 일반적인 방법을 논하였다. 이러한 문제의 해를 구하기 위해서는 입자의 중심선을 따라 분포되어 있는 stokeslet으로 수식화된 유동장을 필요로 한다. 입자에 작용하는 수동력학적 힘과 토오크는 이러한 stokeslet의 적분에 의하여 구할 수 있는데 유동특성에 따라 2계 이상 의 텐서에 비례한다. Johnson에 의하여 유도된 적분방정식은 LU-분해법을 사용하여 해를 구하였다. 해석 결과의 정확성은 침상체를 모델로 하여 Brenner의 엄밀해와 비교하였으며, 일치된 결과를 얻었다.

• Communications of the Korean Mathematical Society
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• v.20 no.2
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• pp.365-379
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• 2005

The purpose of this paper is to correct erroneous proofs of theorems of He, Lu, Wang and Zheng [1] about the topological pressure of continuous flows without fixed points and to give proofs of some results which are stated in the literature without proofs and thereby to show that their theorems are still true.