• 제목/요약/키워드: mer

검색결과 306건 처리시간 0.025초

Electronic Spectroscopy and Ligand Field Analysis of mer-[Cr(progly)(2,2-tri)]$CIO_4$

  • Park, Jong-Ha
    • Journal of Photoscience
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    • 제9권3호
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    • pp.51-55
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    • 2002
  • The 77 K emission and excitation spectra, and 298 K infrared and absorption spectra of [Cr(progly)(2,2-tri)]CIO$_4$[progly=prolylglycinate,2,2-tri=N-(2-aminoethyl)-1,2-ethanediamine] have been measured. The vibrational intervals of the electronic ground state are extracted from emission and infrared spectra. The twelve electronic bands due to spin-allowed and spin-forbidden transitions were assigned. Using the observed electronic transitions, a ligand field analysis was performed to determine the metaligand bonding properties for the coordinated atoms. It is found that the carboxylate oxygen of the progly is a strong $\sigma$-and $\pi$-donor while the peptide nitrogen has weak $\pi$-donor property toward chromium(III) ion.

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Secrecy Analysis of Amplify-and-Forward Relay Networks with Beamforming

  • Chen, Pu;Ouyang, Jian;Zhu, Wei-Ping
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권10호
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    • pp.5049-5062
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    • 2016
  • This paper analyzes the secrecy performance of an amplify-and-forward (AF) relay network, where a multi-antenna eavesdropper attempts to overhear the transmitted message from a multi-antenna source to a multi-antenna destination with a single antenna relay. Firstly, we derive the approximate analytical expressions for the secrecy outage probability (SOP) and average secrecy rate (ASR) of the relay network. Then, asymptotic expressions of SOP and ASR at high main-to-eavesdropper ratio (MER) are also provided to reveal the diversity gain of the secure communication. Finally, numerical results are given to verify the theoretical analysis and show the effect of the number of antennas in the considered relay network.

Optimized Methods for purification and NMR measurement of antibacterial peptide, bovine lactophoricin

  • Kim, Ji-Sun;Park, Tae-Joon;Kim, Yong-Ae
    • 한국자기공명학회논문지
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    • 제13권2호
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    • pp.96-107
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    • 2009
  • Lactophoricin (LPcin-I) is a cationic amphipathic peptide with 23-mer peptide, and corresponds to the carboxy terminal 113-135 region of Component-3 of proteose-peptone. LPcin-I is a good candidate as a peptide antibiotic, because it has an antibacterial activity, but no hemolytic activity. On the other hand, its shorter analog (LPcin-II), which corresponds to the 119-135 region of PP3, has no antibacterial activity. In order to understand the structure-activity relationship under the membrane environments, we succeed to produce large amounts of LPcin-I and LPcin-II peptides. Peptides were over expressed in the form of fusion protein in Escherichia coli, and purified with several chromatography techniques. In this paper, we introduce the optimizing processes of purification and NMR measurement.

심혈관계 질환 진단용 DNA 컴퓨팅 시스템 모듈로서의 C-반응 단백질-결합 앱타머 개발 (Construction of C-Reactive Protein-Binding Aptamer As A Module of the DNA Computing System for Diagnosing Cardiovascular Diseases)

  • 김수동;류재송;김성천;장병탁
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (B)
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    • pp.307-309
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    • 2004
  • 급성 심근경색 진단용 DNA 컴퓨팅 시스템 모듈로서, 트로포닌 I (troponin I, Tnl). 트로포닌 T (troponin T, TnT). 미오글로빈 (myoglobin), C-반응 단백질 (C-reactive protein, CRP) 과 각각 결합할 수 있는 네 가지 종류의 앱타머틀 선정하고, 이의 개발을 시도하여, 그 중 첫 번째로 C-반응 단백질-결합 앱타머를 SELEX 기법을 이용하여 선별해내었다. 또한, 선별된 앱타머 염기서열에 기초하여 각각 10-mer 길이의 FDNA 와 QDNA 를 제작하고, 표적 단백질 (CRP) 과 혼합시켜 형광발현 변화의 추이를 살펴보았다. 앱타머 및 FDNA. QDNA 가 결합할 경우에는 형광감쇄효과가 발생하므로, 형광감쇄효과가 일어나지 않은 경우에 비하여 현저하게 형광측정값이 저조하게 나타나는 현상을 확인할 수 있었다. 향후 연구로, 나머지 세 가지 종류의 앱타머를 SELEX기법을 이용하여 선별해내고. 기확보된 C-반응 단백질-결합 앱타머 모듈과 함께 논리회로를 구성하는 DNA 컴퓨팅 칩을 제작할 예정이다.

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Preparation of 2,9-Dimethyl-6H,13H-dibenzo[d,i][1,6]dithiecin-7,14dlone by Sodium Azide-Promoted Cyclodimeri-zation of o-Acylthiophenacyl Chloride

  • 유성우;김민경;이기정
    • Bulletin of the Korean Chemical Society
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    • 제21권8호
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    • pp.797-800
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    • 2000
  • The reaction of o-acylthiophenacyl chloride 5a with onc equivalent ofsodium azide in aqueous acetone at-10~ $-5^{\circ}C$ gave 2,9-dimethyl-6H,I3H-dibenzo[d,i][1,6]dithiecin-7,14-dione 7(10%),acyclic dimer 8(64%),and tri-mer 9 (8%). Dimer 8 and trimer 9 we re converted readily to 7 under the similar conditions at room temperature in yields of 72% and 53%,respectivel. Also, one pot synthesis of 7 (64%, 45%) from the reaction of 5a or 5b with two equivalents of sodium azide at room temperature was very successful.

Electrochemical Behaviour of merdional tris(2-pyridinethiolato)Cobalt(Ⅲ) in Dimethylformamide Solution

  • 천정균;Chae, Hee K.;김용태;고용복;정옥상
    • Bulletin of the Korean Chemical Society
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    • 제18권5호
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    • pp.496-500
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    • 1997
  • Electrochemical behavior of mer-tris(2-pyridinethiolato)cobalt(Ⅲ) in dimethylformamide was studied on a platinum electrode by means of cyclic voltammetry, chronoamperometry, and chronocoulometry. It was found that the neutral complex molecule was electroactive between the potential region of 1.0 and - 1.2 V vs. a nonaqueous Ag/Ag+ electrode. The Co(Ⅲ) complex was reversibly reduced to Co(Ⅱ) species by one-electron transfer at about - 1.1 V, followed by an irreversible dissociation reaction. However, the oxidation process at around 0.8 V, was responsible for an irreversible two-electron transfer that occurred at a ligand site.

Synthesis and Antibiotic Activities of CRAMP, a Cathelin-related Antimicrobial Peptide and Its Fragments

  • 하종명;신송엽;강신원
    • Bulletin of the Korean Chemical Society
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    • 제20권9호
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    • pp.1073-1077
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    • 1999
  • CRAMP, a 37-amino acid cationic antimicrobial peptide was recently deduced from the cDNA cloned from mouse femoral marrow RNA. In order to investigate the structure-activity relationship and functional region of CRAMP, CRAMP and its 18-mer overlapping peptides were synthesized by the solid phase method. CRAMP showed broad spectrum antibacterial activity against both Gram-positive and Gram-negative bacterial strains (MIC: 3.125-6.25 μM) but had no hemolytic activity until 50 μM. CRAMP was found to have a potent anticancer activity (IC50: 12-23 μM) against two human small cell lung cancer cell lines. Furthermore, CRAMP was found to display faster bactericidal rate in B. subtilis rather than E. coli in the kinetics of bacterial killing. Among 18-meric overlapping fragment peptides, only CRAMP (16-33) displayed potent antibacterial activity (MIC: 12.5-50 μM) against several bacteria with no hemolytic activity. Circular dichroism (CD) spectra anal-ysis indicated that CRAMP and its analogues will form the amphipathic α-helical conformation in the cell membranes similar to other antimicrobial peptides, such as cecropins and magainins.

Draft genome of Semisulcospira libertina, a species of freshwater snail

  • Gim, Jeong-An;Baek, Kyung-Wan;Hah, Young-Sool;Choo, Ho Jin;Kim, Ji-Seok;Yoo, Jun-Il
    • Genomics & Informatics
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    • 제19권3호
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    • pp.32.1-32.10
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    • 2021
  • Semisulcospira libertina, a species of freshwater snail, is widespread in East Asia. It is important as a food source. Additionally, it is a vector of clonorchiasis, paragonimiasis, metagonimiasis, and other parasites. Although S. libertina has ecological, commercial, and clinical importance, its whole-genome has not been reported yet. Here, we revealed the genome of S. libertina through de novo assembly. We assembled the whole-genome of S. libertina and determined its transcriptome for the first time using Illumina NovaSeq 6000 platform. According to the k-mer analysis, the genome size of S. libertina was estimated to be 3.04 Gb. Using RepeatMasker, a total of 53.68% of repeats were identified in the genome assembly. Genome data of S. libertina reported in this study will be useful for identification and conservation of S. libertina in East Asia.

표 질의응답을 위한 언어 모델 학습 및 데이터 구축 (Pre-trained Language Model for Table Question and Answering)

  • 심묘섭;전창욱;최주영;김현;장한솔;민경구
    • 한국정보과학회 언어공학연구회:학술대회논문집(한글 및 한국어 정보처리)
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    • 한국정보과학회언어공학연구회 2021년도 제33회 한글 및 한국어 정보처리 학술대회
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    • pp.335-339
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    • 2021
  • 기계독해(MRC)는 인공지능 알고리즘이 문서를 이해하고 질문에 대한 정답을 찾는 기술이다. MRC는 사전 학습 모델을 사용하여 높은 성능을 내고 있고, 일반 텍스트문서 뿐만 아니라 문서 내의 테이블(표)에서도 정답을 찾고자 하는 연구에 활발히 적용되고 있다. 본 연구에서는 기존의 사전학습 모델을 테이블 데이터에 활용하여 질의응답을 할 수 있는 방법을 제안한다. 더불어 테이블 데이터를 효율적으로 학습하기 위한 데이터 구성 방법을 소개한다. 사전학습 모델은 BERT[1]를 사용하여 테이블 정보를 인코딩하고 Masked Entity Recovery(MER) 방식을 사용한다. 테이블 질의응답 모델 학습을 위해 한국어 위키 문서에서 표와 연관 텍스트를 추출하여 사전학습을 진행하였고, 미세 조정은 샘플링한 테이블에 대한 질문-답변 데이터 약 7만건을 구성하여 진행하였다. 결과로 KorQuAD2.0 데이터셋의 테이블 관련 질문 데이터에서 EM 69.07, F1 78.34로 기존 연구보다 우수한 성능을 보였다.

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Whole Genome Sequencing and Gene Prediction of Cynodon transvaalensis

  • Sol Ji Lee;Chang soo Kim
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.237-237
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    • 2022
  • Cynodon transvaalensis belongs to the warm-season grasses and is one of the economically and ecologically important crops. Cynodon species with high heterozygosity are difficult to assemble, so genome research has not been actively conducted. In this study, hybrid assembly was performed by sequencing with Illumina and PacBio. As a result of the assembly, the number of scaffolds and the length of N50 were 1,392, 928 kb, respectively. The completeness of the assembly was confirmed by BSUCO at 98.3%. In addition, as a result of estimating the size of the assembled genome by K-mer analysis (k=25), it was approximately ~413 Mb. A total of 37,060 cds sequences were annotated in the assembled genome, and their functions were identified through blast. After that, we try to complete the assembled genome into a pseudochromosome-level genome through Hi-C technology. These results will not only help to understand the complex genome composition of african bermudagrass, but also provide a resource for genomic and evolutionary studies of grass and other plant species.

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