• 약학회지
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• 제58권4호
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• pp.245-249
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• 2014

Murrayafoline-A (1-methoxy-3-methylcarbazole) is a monomeric carbazole alkaloid found in Murraya euchrestifolia HAYATA and Glycosmis stenocarpa. We have recently shown that murrayafoline-A has positive inotropic effect in isolated rat ventricular myocytes. To know possible mechanisms for the positive inotropic effect of murrayafoline-A we examined the effects of murrayafoline-A on in situ behavior of cardiac $Ca^{2+}$ release units ('$Ca^{2+}$ sparks') and sarcoplasmic reticulum (SR) $Ca^{2+}$ loading using confocal $Ca^{2+}$ imaging method in single rat ventricular myocytes. Murrayafoline-A significantly increased the frequency (events/($10^3{\mu}m^2{\cdot}s$)) of $Ca^{2+}$ sparks in a concentration-dependent manner, with an $EC_{50}$ of $28{\pm}6.4{\mu}M$ and a maximal ~twofold change. The $Ca^{2+}$ content in the SR, measured as caffeine (10 mM)-induced $Ca^{2+}$ transient, was significantly increased by murrayafoline-A (${\approx}$116% and ${\approx}$123% of control at 25 and 100 ${\mu}M$, respectively). In addition, murrayafoline-A significantly increased the fractional $Ca^{2+}$ release, suggesting increase in the efficacy of $Ca^{2+}$ release at given SR $Ca^{2+}$ loading. These results suggest that murrayafoline-A may enhance contractility via increase in $Ca^{2+}$ release from the SR through the ryanodine receptors in ventricular myocytes.

• Bulletin of the Korean Chemical Society
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• 제10권6호
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• pp.582-585
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• 1989

Two crystal structures of dehydrated $Sr^{2+}\;and\;Tl^+$ exchanged zeolite A, $Sr_xTl_{12-2x}-A$ (x = 1.6 and 5.45), have been determined by single-crystal X-ray diffraction techniques. Their structures were solved and refined in the cubic space group Pm3m at $21(1)^{\circ}C.$ Both crystals were ion exchanged in flowing streams of mixed $Sr(NO_3)_2\;and\;TlNO_3$ aqueous solution, followed by dehydration at $360^{\circ}C\; and\; 2${\times}$10^{-6}$ Torr for 2 days. Full-matrix least-squares refinements of the dehydrated $Sr_{1.6}Tl_{8.8}-A (a = 12.214(2){\AA})\; and\;Sr_{5.45}Tl{1.1}-A (a=12.291(2){\AA})$ have converged to final error indices, $R_1=0.055\; and\;R_2=0.061$ with 286 reflections, and R1 = 0.072 and R2 = 0.090 with 217 reflections, respectively, for which$\;I\;{>}\;3{\sigma}(I)$. In both structures, all Sr(II) ions are coordinated by three framework oxygens; Sr(II) to O(3) distances are $2.21(2){\AA}\;for\;Sr_{1.6}Tl_{8.8}-A \;and\;2.31(1){\AA} \;for\;Sr_{5.45}Tl_{1.1}-A,$and Tl(I) to O(3) distances are $2.657(6){\AA}\;for\;Sr_{1.6}Tl_{8.8}-A\;and\;2.845(8){\AA}\;for\;Sr_{5.45}Tl_{1.1}-A,$ respectively. In each structure, the angle subtended at Sr(II), O(3)-Sr(II)-O(3) is $118.7(4)^{\circ}\;for\; Sr_{1.6}Tl_{8.8}-A \;and\;120.0(4)^{\circ}\;for\;Sr_{5.45}Tl_{1.1}-A.\;Sr^{2+}$ ions prefer to 6-ring sites and $Tl^+$ ions to 8-ring sites when total number of ions per unit cell is more than 8.

• 대한화학회지
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• 제51권1호
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• pp.31-35
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• 2007

트리포달 구리(II) 착물 [Cu(pmea)(H2O)](ClO4)2·H2O (1) (pmea=bis[(2-pyridyl)methyl]-2-(2-pyridyl)-ethylamine)을 합성하고 X-선 회절법으로 구조를 규명하였다. 이 착물은 삼사정계, 공간군 P-1, a = 9.9362(9) A, b = 15.7299(17) A, c = 18.0562(11) A, α = 68.760(8)°, β = 76.331(6)°, γ = 77.092(9)°, V = 2526.2(4) A3, Z = 2로 결정화 되었다. 각각의 구리 원자는 약간 일그러진 사각뿔 구조를 갖는데, 바탕 면은 pmea 리간드에 있는 세 개의 질소원자와 물 분자가 포함되어 있으며 축 방향에는 피리딘 고리의 질소 원자가 포함되어있다. 착물 1의 순환 전압전류 그림은 가역 일-전자 산화 CuIII 및 환원 CuI 과정으로 진행됨을 보여주었다.

• E2M - 전기 전자와 첨단 소재
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• 제9권4호
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• pp.415-421
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• 1996

본 고에서는 고온센서용 압전체가 필요하고 실용화할 수 있는 다결정 압전세라믹스 및 박막재료가 요구되는 점을 감안하여 고온에서도 사용할 수 있는 단결정 $A_{2}$B$_{2}$O$_{2}$형의 성장과 그 전기적 특성 및 최근 개발을 시도하고 있는 다결정 $A_{2}$B$_{2}$O$_{2}$형 압전체에 대한 지금까지의 개발동향을 문헌소개와 함께 필자의 연구결과 일부도 보고하며 아울러 박막화의 가능성도 제시하고자 한다.

• 대한화학회지
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• 제43권4호
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• pp.12-494
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• 1999

• Clinical and Experimental Pediatrics
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• 제46권4호
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• pp.340-344
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• 2003

목 적 : RDS 발생과 BPD로의 이행을 예측 할 수 있고, 스테로이드 치료에 새로운 지표로서 사용 될 수 있는 SP-A2의 유전자 대립형질의 한국분포 및 빈도를 밝히고 새로운 종류의 유전자 대립형질을 발견하기 위하여 본 연구를 하였다. 방 법 : 2002년 4월부터 2002년 6월까지 순천향대학교 천안병원과 경희대학교병원 신생아실에 입원한 정상 신생아 71명을 대상으로 하였다. SP-A2 유전자의 대립 형질을 위하여 시발체(primer) 726/96, 727/21, 799/28A, 805/494를 이용하여 증폭시킨 후 9, 91, 140, 223위치의 뉴클레오티드(nucleotide)를 알아 보기 위하여 각 위치에 맞는 제한 효소(restriction enzyme)를 이용하여(PCR-cRFLP-based methodology) 자른 후 전기 영동하여 염기서열의 차이를 알아냈다. 결 과 : 아미노산 염기서열의 차이에 의하여, 1A, $1A^0$, $1A^1$, $1A^2$, $1A^3$, $1A^5$, $1A^6$, $1A^7$, $1A^8$, $1A^9$, $1A^{11}$, $1A^{12}$ 등의 12개의 대립형질이 발견되었으며, SP-A2 중 1A=11.3%, $1A^0=38%$, $1A^1=12.7%$, $1A^2=9.2%$, $1A^5=15.5%$, $1A^7=2.9%$, $1A^8=4.9%$, $1A^9=2.2%$, others=3.3%의 분포를 보였다. 결 론 : RDS에 대해 보호체(protector)로 작용하는 $1A^5$의 빈도가 많은 것으로 보아 실질적으로도 우리나라에서 RDS의 발생률이 적을 것으로 생각된다. 스테로이드를 사용 할 때 유전자 발현에 많은 억제를 보이는 1A도 우리나라에서 많은 빈도를 보이므로 스테로이드 치료에 있어서 치료에 신중을 기해야겠다.

• 한국세라믹학회지
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• 제36권7호
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• pp.762-766
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• 1999

The crystal structure of A2+(Mg1/3Nb2/3)O3,(A2+=Sr2+ and Ca2+)ceramics was studied usig X-ray diffraction (XRD) and high resolution transmission electrion microscopy(HRTEM). Ba(Mg1/3Nb2/3)O3 (SMN) has the 1:2 ordered monoclinic structure which has the anti-phase tilt of octahedra. The type of tilting in SMN was considered to be a$^{\circ}$a$^{\circ}$c- or a­a­c$^{\circ}$ Ca(Mg1/3Nb2/3)O3 (CMN) also has the 1:2 ordered monoclinic structure which was distorted by the anti-phase tilt or in-phsae tilt of octahedra. A unit cell containing both the in-phase tilt axis and anti-phase tilt axis was not observed in the CMN. Therefore CMN has the mixed phase consisting of the 1:2 ordered monoclinic phase with anti-phase tilt of octahedra and the one with in -phase tilt of ocatahedra,. The anti-parallel shift of cation was also observed in the CMN.

• 호남수학학술지
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• 제32권2호
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• pp.255-260
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• 2010

Given vectors x and y in a separable complex Hilbert space $\mathcal{H}$, an interpolating operator is a bounded operator A such that Ax = y. In this article, we investigate compact interpolation problems for vectors in a tridiagonal algebra. We show the following : Let Alg$\mathcal{L}$ be a tridiagonal algebra on a separable complex Hilbert space $\mathcal{H}$ and let x = $(x_i)$ and y = $(y_i)$ be vectors in H. Then the following are equivalent: (1) There exists a compact operator A = $(a_{ij})$ in Alg$\mathcal{L}$ such that Ax = y. (2) There is a sequence ${{\alpha}_n}$ in $\mathbb{C}$ such that ${{\alpha}_n}$ converges to zero and for all k ${\in}$ $\mathbb{N}$, $y_1 = {\alpha}_1x_1 + {\alpha}_2x_2$ $y_{2k} = {\alpha}_{4k-1}x_{2k}$ $y_{2k+1}={\alpha}_{4k}x_{2k}+{\alpha}_{4k+1}x_{2k+1}+{\alpha}_{4k+2}+x_{2k+2}$.

• Journal of Microbiology and Biotechnology
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• 제33권8호
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• pp.1050-1056
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• 2023

Weizmannia coagulans (formerly Bacillus coagulans) is Gram-positive, and spore-forming bacteria causing food spoilage, especially in acidic canned food products. To control W. coagulans, we isolated a bacteriophage Youna2 from a sewage sludge sample. Morphological analysis revealed that phage Youna2 belongs to the Siphoviridae family with a non-contractile and flexible tail. Youna2 has 52,903 bp double-stranded DNA containing 61 open reading frames. There are no lysogeny-related genes, suggesting that Youna2 is a virulent phage. plyYouna2, a putative endolysin gene was identified in the genome of Youna2 and predicted to be composed of a N-acetylmuramoyl-L-alanine amidase domain (PF01520) at the N-terminus and unknown function DUF5776 domain (PF19087) at the C-terminus. While phage Youna2 has a narrow host range, infecting only certain strains of W. coagulans, PlyYouna2 exhibited a broad antimicrobial spectrum beyond the Bacillus genus. Interestingly, PlyYouna2 can lyse Gram-negative bacteria such as Escherichia coli, Yersinia enterocolitica, Pseudomonas putida and Cronobacter sakazakii without other additives to destabilize bacterial outer membrane. To the best of our knowledge, Youna2 is the first W. coagulans-infecting phage and we speculate its endolysin PlyYouna2 can provide the basis for the development of a novel biocontrol agent against various foodborne pathogens.

• 충청수학회지
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• 제32권2호
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• pp.251-260
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• 2019

It has been little known when an Artinian (point) quotient has the strong Lefschetz property. In this paper, we find the Artinian complete intersection quotient having the SLP. More precisely, we prove that if ${\mathbb{X}}$ is a complete intersection in ${\mathbb{P}}^2$ of type (2, 2) and ${\mathbb{Y}}$ is a finite set of points in ${\mathbb{P}}^2$ such that ${\mathbb{X}}{\cup}{\mathbb{Y}}$ is a basic configuration of type (2, a) with $a{\geq}3$ or (3, a) with a = 3, 4, 5, 6, then $R/(I_{\mathbb{X}}+I_{\mathbb{Y}})$ has the SLP. We also show that if ${\mathbb{X}}$ is a complete intersection in ${\mathbb{P}}^2$ of type (3, 2) and ${\mathbb{Y}}$ is a finite set of points in ${\mathbb{P}}^2$ such that ${\mathbb{X}}{\cup}{\mathbb{Y}}$ is a basic configuration of type (3, 3) or (3, 4), then $R/(I_{\mathbb{X}}+I_{\mathbb{Y}})$ has the SLP.