• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2016년도 추계 학술발표논문집
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• pp.111-117
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• 2016

• Bulletin of the Korean Chemical Society
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• 제14권1호
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• pp.113-117
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• 1993

Good yield synthetic routes for the production of new B-alkyl-dithiaborane clusters are reported. The syntheses of the B-alkyl-dithiaboranes are based on the use of Fischer-type carbene reagents to activate the B-H bonds of dithiaborane for alkyl-addition reactions and are the first examples of transition-mediated reactions of dithiaborane to be reported. Thus, reactions employing arachno-$S_2B_7H_8$- and $(CO)_5M{C(R_1)R_2}$ (M = Cr, W; $R_1 = CH_3,\;C_6H_5;\; R_2 = OCH_3,\;SC_6H_5)$ were found to yield the intermidiate anions I, $[(CO)_5M{C(R_1)R_2S_2B_7H_8}]^-$, which upon protonation gave the corresponding neutral, air-sensitive cluster arachno-4-$RCH_2-6,8-S_2B_7H_8(R=CH_3,\;IIa;\;C_6H_5,\;IIb)$ range from 30 to 35% yield. Complexes IIa and IIb are isoelectronic with arachno-6,8-$S_2B_7H_9$ and, on the basis of the spectroscopic data, are proposed to adopt a similar arachno cage geometry in which an $RCH_2$ units are substituted to 4 position boron atom of the arachno-6,8-$S_2B_7H_9$.

• Journal of Plant Biology
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• 제29권1호
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• pp.53-65
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• 1986

The montane forests of Ulreung Island, Korea, were investigated by the ZM school method. By comparing the montane forests of this island with those of Korean Peninsula and of Japan, a new order, F a g e t a l i a m u l t i n e r v i s, a new alliance, F a l g i o n m u l t i n e r v i s, a new association, H e p a t i c o-F a g e t u m m u l t i n e r v i s and Rhododendron brachycarpum-Pinus parviflora community were recognized. The H e p a t i c o - F a g e t u m m u l t i n e r v i s was further subdivided into four subassociations; Subass. of Sasa kurilensis, Subass. of Rumohra standishii, Subass. of Rhododendron brachycarpum and Subass. of typicum. Each community was described in terms of floristic, structural and environmental features.

• Journal of Ginseng Research
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• 제27권3호
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• pp.129-134
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• 2003

When ginsenoside $R_{*}$b1/ and $R_{b2}$ were anaerobically incubated with human fecal microflora, these ginsenosides were metabolized to compound K (IH-901). When ginsenoside $R_{g3}$ was anaerobically incubated with human fecal microflora, the ginsenoside $R_{g3}$ was metabolized it to ginsenoside $R_{h2}$. Among ginsenosides, IH-901 and 20(S)-ginsenoside $R_{h2}$ exhibited the most potent cyotoxicity against tumor cells: 50% cytotoxic concentrations of IH-901 in the media with and without fetal bovine serum (FBS) were 27.1-31.6 $\mu$M and 0.1-0.61 $\mu$M, and those of 20(S)-ginsenoside $R_{h2}$ were 37.5->50 and 0.7-7.1 $\mu$M, respectively. The cytotoxic potency of ginsenosides was IH-901>20(S)-ginsenoside R $h_{h2}$》20(S)-ginsenoside $R_{g3}$>ginsenoside $R_{b1}$(equation omitted) $R_{b2}$.EX>$R_{b2}$./.

• Kyungpook Mathematical Journal
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• 제64권3호
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• pp.417-421
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• 2024

Let R be a commutative ring and let M be an R-module. In this note, we give a brief proof of the Hilbert basis theorem for Noetherian modules. This states that if R contains the identity and M is a Noetherian unitary R-module, then M[X] is a Noetherian R[X]-module. We also show that if M[X] is a Noetherian R[X]-module, then M is a Noetherian R-module and there exists an element e ∈ R such that em = m for all m ∈ M. Finally, we prove that if M[X] is a Noetherian R[X]-module and ann_R(M) = (0), then R has the identity and M is a unitary R-module.

• Journal of Microbiology and Biotechnology
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• 제25권5호
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• pp.672-680
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• 2015

As a global regulatory gene in Streptomyces, afsR can activate the biosynthesis of many secondary metabolites. The effect of afsR on the biosynthesis of a phenazine metabolite, lomofungin, was studied in Streptomyces lomondensis S015. There was a 2.5-fold increase of lomofungin production in the afsR-overexpressing strain of S. lomondensis S015 N1 compared with the wild-type strain. Meanwhile, the transcription levels of afsR and two important genes involved in the biosynthesis of lomofungin (i.e., phzC and phzE) were significantly upregulated in S. lomondensis S015 N1. The optimization of metal chlorides was investigated to further increase the production of lomofungin in the afsR-overexpressing strain. The addition of different metal chlorides to S. lomondensis S015 N1 cultivations showed that CaCl₂, FeCl₂, and MnCl₂ led to an increase in lomofungin biosynthesis. The optimum concentrations of these metal chlorides were obtained using response surface methodology. CaCl₂ (0.04 mM), FeCl₂ (0.33 mM), and MnCl₂ (0.38 mM) gave a maximum lomofungin production titer of 318.0 ± 10.7 mg/l, which was a 4.1-fold increase compared with that of S. lomondensis S015 N1 without the addition of a metal chloride. This work demonstrates that the biosynthesis of phenazine metabolites can be induced by afsR. The results also indicate that metal chlorides addition might be a simple and useful strategy for improving the production of other phenazine metabolites in Streptomyces.

• 대한수학회지
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• 제48권6호
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• pp.1189-1201
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• 2011

Let R be a ring and M a right R-module, S = $End_R$(M). The module M is called almost principally small injective (or APS-injective for short) if, for any a ${\in}$ J(R), there exists an S-submodule $X_a$ of M such that $l_Mr_R$(a) = Ma $Ma{\bigoplus}X_a$ as left S-modules. If $R_R$ is a APS-injective module, then we call R a right APS-injective ring. We develop, in this paper, APS-injective rings as a generalization of PS-injective rings and AP-injective rings. Many examples of APS-injective rings are listed. We also extend some results on PS-injective rings and AP-injective rings to APS-injective rings.

• 식물분류학회지
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• 제39권3호
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• pp.193-198
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• 2009

국내에 자생하는 Maackia속 2종(솔비나무, 다릅나무)의 염색체수 및 핵형을 분석하고 5S와 45S rDNAs를 이용한 bicolor FISH를 수행하였다. 솔비나무와 다릅나무의 체세포 염색체수는 동일하게 2n = 2x = 18로 관찰되었고, 염색체의 길이는 $3.58{\sim}5.82{\mu}m$이였다. 솔비나무의 염색체 조성은 2쌍의 중부 염색체(염색체 1과 7번), 4쌍의 차중부 염색체(염색체 4, 6, 8, 9번), 그리고 3쌍의 차단부 염색체(염색체 2, 3, 5번)로 확인되었다. 다릅나무의 염색체는 4번이 차단부 염색체, 7번이 차중부 염색체로 솔비나무와 차이를 보였으나 다른 염색체의 동원체 위치는 유사하게 관찰되었다. 5S와 45S rDNA를 이용한 FISH 결과, 45S rDNA 유전자는 솔비나무와 다릅나무에서 각각 1쌍으로 관찰되었고 2번 염색체의 2차 협착 부위에서 확인되었다. 5S rDNA유전자를 이용한 물리지도 작성에서는 두 종 사이를 구별할 수 있는 결과를 확인할 수 있었다. 솔비나무의 경우 염색체 7번과 8번의 동원체 부위에서 2쌍이 각각 관찰되었고, 다릅나무에서는 염색체 7번과 8번뿐만 아니라 3번과 4번 염색체에서도 관찰되어 모두 4쌍으로 확인되었다. 따라서, 5S rDNA유전자를 이용한 FISH방법을 통해 세포학적으로 두 종을 구분할 수 있었다.

• 호남수학학술지
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• 제28권3호
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• pp.365-376
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• 2006

Let R be a commutative ring and let M be an R-module. Let X = $Spec_R(M)$ be the prime spectrum of M with Zariski topology. In this paper, by using the topological properties of X, we will obtain some conditions under which $Max_R(M)=Spec_R(M)$.

• Journal of Chest Surgery
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• 제14권3호
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• pp.235-240
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• 1981

A total of 102 patients who had an Open Heart Surgery from April 1976 to July 1981 were reviewed. 55 paeitnts were congenital heart disease and 47 patients were acquired heart disease. Among SS patients of congenital heart disease, 18 T 0 F, 18 V S D, 8 A S D, and each one case of l\ulcorner 0 R V, Truncus arteriosus, Ebstein anomaly, Single ventricle, P D A, P 5, A S D + P 5, E C D, V 5 D + P D A, A - P window, D C R V were noted respectively. In 47 patients of acquired heart disease and one Ebstein patient, 46 prosthetic values were implanted: 17 had M V R, 4 had A V R, 2 had M V R + A V R, and 4 had M V R + T V R and one T V R. The operative mortality was 8.S% in acquired heart disease and 17% in congenital heart disease. The follow up period was between 6 months and 6 years. There were 3 cases of late mortality in acquired heart disease and one case in congenital heart disease.