• 식물분류학회지
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• 제44권3호
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• pp.191-201
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• 2014

동아시아산 황기속의 외부형태학적 특징과 과피, 종피의 해부구조 및 표면 형태를 조사하여 분류학적으로 유용한 형질을 찾고자 하였다. 연구 결과, 황기속의 외부형태, 과피, 종피의 형태 및 해부학적 특징 중 생활사, 소엽의 형태, 꽃차례, 꽃잎의 색, 종자의 색, 과피의 형태, 과피 표면에서 털의 존재유무, 봉선의 구조, 그리고 내과피 층의 두께가 종을 나누는 식별형질로 사용될 수 있음을 확인하였다. 이를 바탕으로 중국에서 황기라는 약재로 사용되어지고 있는 4종의 형태 및 해부학적인 특성을 비교한 결과, 서로 같은 군으로 유집되었다. 한편, 분류학적으로 논쟁이 되고 있는 정선황기와 갯황기에서는 두 분류군간에 형태적 차이점을 발견 할 수 없었다. 따라서 금후 정선황기, 갯황기, A. bhotanensis의 종간 분류학적 처리를 명확히 규명하기 위하여 염기서열 및 분자세포학 수준에서의 연구가 필요하다.

• International Journal of Concrete Structures and Materials
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• 제9권3호
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• pp.345-367
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• 2015

Past earthquakes have signaled the increased collapse vulnerability of mainshock-damaged bridge piers and urgent need of repair interventions prior to subsequent cascading hazard events, such as aftershocks, triggered by the mainshock (MS). The overarching goal of this study is to quantify the collapse vulnerability of mainshock-damaged substandard RC bridge piers rehabilitated with different repair jackets (FRP, conventional thick steel and hybrid jacket) under aftershock (AS) attacks of various intensities. The efficacy of repair jackets on post-MS resilience of repaired bridges is quantified for a prototype two-span single-column bridge bent with lap-splice deficiency at column-footing interface. Extensive number of incremental dynamic time history analyses on numerical finite element bridge models with deteriorating properties under back-to-back MS-AS sequences were utilized to evaluate the efficacy of different repair jackets on the post-repair behavior of RC bridges subjected to AS attacks. Results indicate the dramatic impact of repair jacket application on post-MS resilience of damaged bridge piers-up to 45.5 % increase of structural collapse capacity-subjected to aftershocks of multiple intensities. Besides, the efficacy of repair jackets is found to be proportionate to the intensity of AS attacks. Moreover, the steel jacket exhibited to be the most vulnerable repair intervention compared to CFRP, irrespective of the seismic sequence (severe MS-severe or moderate AS) or earthquake type (near-fault or far-fault).

• Archives of Pharmacal Research
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• 제25권1호
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• pp.11-24
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• 2002

The antitumor antibiotic (+)-CC-1065 can alkylate N3 of guanine in certain sequences. A previous high-field $^1H$ NMR study on the$(+)-CC-1065d[GCGCAATTG*CGC]_2$ adduct ($^*$ indicates the drug alkylation site) showed that drag modification on N3 of guanine results in protonation of the cross-strand cytosine [Park, H-J.; Hurley, L. H. J. Am. Chem. Soc.1997, 119,629]. In this contribution we describe a further analysis of the NMR data sets together with restrained molecular dynamics. This study provides not only a solution structure of the (+)-CC-1065(N3- guanine) DNA duplex adduct but also new insight into the molecular basis for the sequence- specific interaction between (+)-CC-1065 and N3-guanine in the DNA duplex. On the basis of NOESY data, we propose that the narrow minor groove at the 7T8T step and conformational kinks at the junctions of 16C17A and 18A19T are both related to DNA bending in the drugDNA adduct. Analysis of the one-dimensional $^1H$ NMR (in $H_2O$) data and rMD trajectories strongly suggests that hydrogen bonding linkages between the 8-OH group of the (+)-CC-1065 A-sub-unit and the 9G10C phosphate via a water molecule are present. All the phenomena observed here in the (+)-CC-1065(N3-guanine) adduct at 5'$-AATTG^*$are reminiscent of those obtained from the studies on the (+)-CC-1065(N3-adenine) adduct at $5'-AGTTA^*$, suggesting that (+)-CC-1065 takes advantage of the conformational flexibility of the 5'-TPu step to entrap the bent structure required for the covalent bonding reaction. This study reveals a common molecular basis for (+)-CC-1065 alkylation at both $5'-TTG^*$ and $5'-TTA^*$, which involves a trapping out of sequence-dependent DNA conformational flexibility as well as sequence-dependent general acid and general base catalysis by duplex DNA.