• International Journal of Oral Biology
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• v.46 no.4
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• pp.190-199
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• 2021

Despite evidence that bacteria-sensing Toll-like receptors (TLRs) are activated in salivary gland tissues of Sjogren syndrome (SS) patients, the role of oral bacteria in SS etiopathogenesis is unclear. We previously reported that two SS-associated oral bacteria, Prevotella melaninogenica (Pm) and Rothia mucilagenosa (Rm), oppositely regulate the expression of major histocompatibility complex class I (MHC I) in human salivary gland (HSG) cells. Here, we elucidated the mechanisms underlying the differential regulation of MHC I expression by these bacteria. The ability of Pm and Rm to activate TLR2, TLR4, and TLR9 was examined using TLR reporter cells. HSG cells were stimulated by the TLR ligands, Pm, and Rm. The levels of MHC I expression, bacterial invasion, and viability of HSG cells were examined by flow cytometry. The hypoxic status of HSG cells was examined using Hypoxia Green. HSG cells upregulated MHC I expression in response to TLR2, TLR4, and TLR9 activation. Both Pm and Rm activated TLR2 and TLR9 but not TLR4. Rm-induced downregulation of MHC I strongly correlated with bacterial invasion and cell death. Rm-induced cell death was not rescued by inhibitors of the diverse cell death pathways but was associated with hypoxia. In conclusion, Pm upregulated MHC I likely through TLR2 and TLR9 activation, while Rm-induced hypoxia-associated cell death and the downregulation of MHC I, despite its ability to activate TLR2 and TLR9. These findings may provide new insight into how oral dysbiosis can contribute to salivary gland tissue damage in SS.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.903-907
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• 2002

• Bulletin of the Korean Chemical Society
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• v.23 no.4
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• pp.629-633
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• 2002

• The Pure and Applied Mathematics
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• v.15 no.4
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• pp.401-406
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• 2008

Given operators X and Y acting on a separable complex Hilbert space H, an interpolating operator is a bounded operator A such that AX=Y. In this article, we investigate Hilbert-Schmidt interpolation problems for operators in a tridiagonal algebra and we get the following: Let ${\pounds}$ be a subspace lattice acting on a separable complex Hilbert space H and let X=$(x_{ij})$ and Y=$(y_{ij})$ be operators acting on H. Then the following are equivalent: (1) There exists a Hilbert-Schmidt operator $A=(a_{ij})$ in Alg${\pounds}$ such that AX=Y. (2) There is a bounded sequence $\{{\alpha}_n\}$ in $\mathbb{C}$ such that ${\sum}_{n=1}^{\infty}|{\alpha}_n|^2<{\infty}$ and $$y1_i={\alpha}_1x_{1i}+{\alpha}_2x_{2i}$$ $$y2k_i={\alpha}_{4k-1}x_2k_i$$ $$y{2k+1}_i={\alpha}_{4k}x_{2k}_i+{\alpha}_{4k+1}x_{2k+1}_i+{\alpha}_{4k+2}x_{2k+2}_i\;for\;all\;i,\;k\;\mathbb{N}$$.

• Journal of the Korean Chemical Society
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• v.47 no.1
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• pp.26-30
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• 2003

The dinuclear $Ag_2[Phen]_2[S_2P(OPr)_2]_2$(phen=1,10-phenanthroline; Pr=propyl), was prepared by the reaction of bis(dipropyldithiophosphato) silver(I) complex with 1,10-phenanthroline ligand, and its structure was determined by X-ray crystallography. The two dipropyldithiophosphato ligands each bridge two silver atoms to form an eight-membered $Ag_2S_4P_2$ ring, while the 1,10-phenanthroline molecule coordinates to a silver atom to complete the local tetrahedral geometry for the metal ion. The Ag-S bond distances are 2.559(1) and 2.567(1)${\AA}$, and the Ag-N bond distances are 2.366(3) and 2.471(3)${\AA}$.

• School Mathematics
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• v.9 no.2
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• pp.291-312
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• 2007

As a result of observing the 10-th grade text books on mathematics now in use which show the way of introducing complex numbers for the first time, it is easy to see all the text books on mathematics use a quadratic equation $x^2+1=0$ for a new number i. However, Since using the new number i is artificial, this make students get confused in understanding the way of introducing complex numbers. And students who have problems with the quadratic equation can also have difficulty in understanding complex numbers. On the other hand, by using a coordinate plane with ordered pairs and arrows, students can understand complex numbers better because the number system can be extended systematically through intuitive methods. The problem is that how to bring and use ordered pairs and arrows to introduce complex numbers in highschool mathematics. To solve this problem, in this study, We developed a systematic and visible learning contents which make it possible to study the process of the step-by-step extension of number system that will be applied through elementary and middle school curriculum and all the way up to the introduction of complex numbers. After having applied the developed learning contents to the teaching and learning procedure, we can know that the developed learning contents are more efficient than the contents used in the text books on mathematics now in use.

• Journal of the Korean Mathematical Society
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• v.32 no.3
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• pp.401-413
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• 1995

This paper is concerned with the problem given below $$ (1.1) i\frac{dx}{du_1(x,\lambda)} + q1(x)u_2(x,\lambda) = \lambdau_1(x,\lambda) 0 \leq x < \infty - i\frac{dx}{du_2(x,\lambda)} + q2(x)u_1(x,\lambda) = \lambdau_2(x,\lambda), $$ $$ (2) u_2(0,\lambda) - hu_1(0,\lambda) = 0 $$ where $\lambda$ is a complex parameter and h is a non-zero complex number.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1638-1640
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• 2006

A variety of chiral cyanohydrins were readily prepared from aldehydes with TMSCN under the influence of chiral titanium complex formed in situ from $Ti(O^iPr)_4$/TADDOL(I) in the presence of $Ph_3PO$ as additive. The double activation method produces trimethylsilylethers in excellent yield (95%) with moderate enantiomeric excess.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.388-391
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• 2002

의류용 소재의 다양화와 소재의 복합화에 따라 최근 여러 가지의 합성섬유 관련소재가 선을 보이고 있다. 그 중 double covering two way 이질 복합사 제품은 high touch 및 fashion 용 차별용도의 최적소재를 도출하여 기존의 제품과는 차별화 할 수 있다는 점과, 기존 제품과는 그 물성이 전혀 다른 새로운 소재의 제품을 생산함에 따라 품질 고급화에 크게 기여할 수 있다는 점에서 그 중요성을 가지고 있다. (중략)

• Bulletin of the Korean Mathematical Society
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• v.44 no.2
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• pp.337-350
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• 2007

Given a collection of complex numbers ${\gamma}{\equiv}\{{\gamma}ij\}$ $(0{\leq}i+j{\leq}2n,\;|i-j|{\leq}n)$ with ${\gamma}00>0\;and\;{\gamma}ji=\bar{\gamma}ij$, we consider the moment problem for ${\gamma}$ in the case of n=2, which is referred to Embry quartic moment problem. In this note we give a partial solution for the nonsingular case of Embry quartic moment problem.