• BMB Reports
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• 제33권1호
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• pp.49-53
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• 2000

PMAP-23 is a 23-residue antimicrobial peptide derived from porcine myloid cells. In order to investigate the effects of two Pro residues at positions 12 and 15 of PMAP-23 on antibiotic activity, two analogues in which Ala was substituted for Pro residue at position 12 or 15 were synthesized. $Pro^{12}{\rightarrow}Ala$ (PMAPl) or $Pro^{15}{\rightarrow}Ala$(PMAP2) substitution in PMAP-23 caused a significant reduction on antitumor and phospholipid vesicle-disrupting activities, but did not cause a significant effect on antibacterial activity. PMAP-23 displayed the type I ${\beta}-turn$ structure with a negative ellipticity at near 205 om in SDS micelle, whereas PMAP1 and PMAP2 had a somewhat ${\alpha}-helical$ propensity in TFE solution, as compared to PMAP-23. These results suggest that two Pro residues of positions 12 and 15 in PMAP-23 play important roles in the formation of ${\beta}-turn$ structure on lipid membrane and its ${\beta}-turn$ structure may be essential for antibiotic activity including phospholipid vesicle-disrupting property.

• 대한토목학회논문집
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• 제12권4_1호
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• pp.9-21
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• 1992

논문에서는 주구조물의 기초와 부구조물의 지지점에 설치된 감진장치가 구조물의 지진응답 감소에 미치는 영향을 분석하였다. 여러가지 지진하중의 특성에 따른 감진장치가 설치된 주구조물과 부구조물의 거동을 비교분석하였으며, 이때 사용된 해석모델은 고정기초 구조물에 지지점이 고정된 부구조물, 감진기초 구조물에 지지점이 고정된 부구조물, 고정기초 구조물에 지지점 감진장치가 설치된 부구조물과 같은 세가지이다. 부구조물의 응답계산에서는 주구조물과 부구조물의 상호작용을 고려하였다. 계산에 사용한 수치적분방법은 constant average acceleration 방법이며, 이 방법과 축소행렬방법을 이용한 전산프로그램(KBISAP)을 사용하였다. 또한 지진하중에 대한 구조물의 지면에 대한 상대변위를 제한시키기 위하여 여러가지 지진하중에 대한 구조물의 가속도와 변위의 상관관계를 계산하여 감진장치의 적합한 수평강성을 분석하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.294-294
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• 2007

Spinel cathode material $LiMn_2O_4$ is currently studied as a promising cathode material for lithium ion secondary batteries for future applications because of it is low cost, easy to be prepared and capable to be operated in high voltage range. However as a cathode material, $LiMn_2O_4$ performs a poor capacity retention which leads to short cycle life. In this study, stoichiometric $LiMn_2O_4$ was synthesized with granulation method with ion substitution to stabilize its structure and niobium doping to improve its conductivity. These well-mixed powders were calcined at $850^{\circ}C$ for 6 hours and its properties were investigated. Correlations of dopant and electrochemical properties were examined as well.

• ALGAE
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• 제28권4호
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• pp.307-330
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• 2013

The genus Cryptomonas is easily recognized by having two flagella, green brownish color, and a swaying behavior. They have relatively simple morphology, and limited diagnostic characters, which present a major difficulty in differentiating between species of the genus. To understand species delineation and phylogenetic relationships among Cryptomonas species, the nuclear-encoded internal transcribed spacer 2 (ITS2), partial large subunit (LSU) and small subunit ribosomal DNA (rDNA), and chloroplast-encoded psbA and LSU rDNA sequences were determined and used for phylogenetic analyses, using Bayesian and maximum likelihood methods. In addition, nuclear-encoded ITS2 sequences were predicted to secondary structures, and were used to determine nine species and four unidentified species from 47 strains. Sequences of helix I, II, and IIIb in ITS2 secondary structure were very useful for the identification of Cryptomonas species. However, the helix IV was the most variable region across species in alignment. The phylogenetic tree showed that fourteen species were monophyletic. However, some strains of C. obovata had chloroplasts with pyrenoid while others were without pyrenoid, which used as a key character in few species. Therefore, classification systems depending solely on morphological characters are inadequate, and require the use of molecular data.

• Mass Spectrometry Letters
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• 제11권4호
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• pp.65-70
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• 2020

Despite its great success in the field of proteomics, mass spectrometry has limited use for determining structural details of peptides, proteins, and their assemblies. Emerging ion mobility spectrometry-mass spectrometry has enabled us to explore the conformational space of protein ions in the gas phase, and further combinations with the gas-phase ion spectroscopy and the collision-induced unfolding have extended its abilities to elucidating the secondary structure and local details of conformational transitions. This review will provide a brief introduction to the combined approaches of IMS-MS with gas-phase ion infrared spectroscopy or collision-induced unfolding and their most recent results that successfully revealed higher-order structural details.

• 한국자기공명학회논문지
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• 제19권2호
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• pp.74-82
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• 2015

Ryanodine receptor (RyR) is one of the two major $Ca^{2+}$ channels in membranes of intracellular $Ca^{2+}$ stores and is found in sarcoplasmic reticulum (SR), endoplasmic reticulum (ER). RyR1 is also the major calmodulin-binding protein of sarcoplasmic reticulum membranes. Residues 4064-4210 in the RyR1 polypeptide chain has similar primary sequence with calmodulin (CaM) and was designated as CaM-like domain (CaMLD). When expressed as a recombinant peptide, CaMLD showed several CaM-like properties in previous studies. Still, previous studies of CaMLD were focused on protein-protein interactions rather than its own properties. Here, we studied the expression of CaMLD and its sub-domains corresponding to each lobe of CaM in Escherichia coli. CaMLD could be obtained only as inclusion body, and it was refolded using urea solubilization followed by dialysis. Using spectroscopic approaches, such as NMR, circular dichroism, and gel filtration experiment, we found that the refolded CaMLD exists as nonspecific aggregate, even though it has alpha helical secondary structure. In comparison, the first half of CaMLD (R4061-4141) could be obtained as natively soluble protein with thioredoxin fusion. After the removal of the fusion tag, it exhibited folded and helical properties as shown by NMR and circular dichroism experiments. Its oligomeric status was different from CaMLD, existing as dimeric form in solution. However, the second half of the protein could not be obtained as soluble protein regardless of fusion tag. Based on these results, we believe that CaMLD, although similar to CaM in sequence, has quite different physicochemical properties and that the second half of the protein renders it the aggregative properties.

• 한국가정과교육학회지
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• 제20권3호
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• pp.65-84
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• 2008

가정교과는 역사적으로 '가정생활의 향상'이나 '가정생활에서의 문제 해결 능력 함양' 등 외재적 목적에 의하여 정당화 되어왔지만, 가정교과의 현실적 상황은 가정교과의 교육내용 자체의 가치에 의한 정당화와 내재적 목적에 대한 이론적 규명을 요구하고 있다. 본 연구는 가정과교육의 내재적 목적을 규명하기 위하여 가정교과의 교육내용으로서 가정학의 지식을 가르치는 것이 교육철학적으로 어떤 의미가 있는지 밝히고자 하였다. 학문중심 교육과정의 관점을 받아들일 때, 가정학은 가정생활 현상에 관한 독자적인 개념, 원리, 지식을 체계화한 '지식의 구조'이며 가정교과의 교육내용으로서 고유하고 독자적인 의미를 가진다. 가정과교육의 내재적 가치와 목적은 이러한 교육내용 안에 들어 있으며, 그 교육내용에서 논리적으로 추론되어 나온다. 가정교과의 내재적 목적은 학습자가 가정교과의 교육내용을 잘 이해하여 일상생활의 사태를 가정학적 관점으로 바라볼 수 있는 안목을 형성하고 확장해나가는 데 있다. 학습자는 이러한 '지적 안목'을 바탕으로 가정생활의 실제 사태에서 주어진 상황을 제대로 '해석'하고 '판단'할 수 있게 된다. '가정생활에 대한 지적 안목'은 가정생활과 관련된 모든 생각과 말과 행동의 원천이 된다는 점에서 가정생활에서의 실제적 문제 해결을 의미 있게 하는 토대가 된다. 따라서 종래의 가정과교육내용이 가정생활에 관한 단편적인 지식이나 사실로 파악되었다면, 가정생활에 대해 폭넓은 안목의 형성에 기여하는 가정학의 지식의 구조로 새롭게 해석되어야 한다. 나아가 가정학 지식의 이해가 학습자의 '가정생활에 관한 지적 안목'으로 통합되도록 가르친다면 가정과교육의 내재적 목적이 실현될 것으로 기대된다.

• 해양환경안전학회지
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• 제29권2호
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• pp.223-229
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• 2023

해수이차전지는 해수를 양극으로 사용하는 차세대 이차전지이다, 해양 자원을 사용하여 가격 경쟁력과 높은 친환경성, 그리고 해양 애플리케이션에 적합한 구조를 가진다. 이러한 장점을 기반으로 지속적 연구개발을 통해 자연 해수 노출을 가정한 파우치 타입 및 각형 타입이 개발되어 왔다. 그러나 이차전지는 전기적 특성상 사용 환경에 따라 용량 및 내부 임피던스가 달라진다. 이러한 특성은 전지의 수명 예측에 활용될 뿐만 아니라 활용하고자 하는 상황에 맞는 용량과 출력에 직접적인 영향을 미친다. 따라서 본 논문에서는 해수이차전지의 사용 환경에 따른 용량 측정과 SoC-OCV 측정 방법을 통한 내부 저항을 분석하고자 한다.

• Applied Microscopy
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• 제24권1호
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• pp.59-76
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• 1994

Fine structure of the distal femoral epiphysis of growing mouse was studied by electron microscopy. The first morphological evidence of developing secondary center of ossification in the distal femoral epiphysis was found at newborn mouse. Ossification center was in the form of multiple foci of calcification and its cells were represented by remnant of degenerated cells within large lacunae that were separated by mineralized cartilaginous septa. Endochondral ossification beneath the articular cartilage proceeded in a less orderly manner than metaphyseal endochondral ossification. Columns of hypertrophied chondrocytes were not distinctly parallel to intercellular mineralized septa in all direction. Hypertrophied chondrocytes in the inner zone of the epiphseal center of ossification showed disintegrated. Resorption of mineralized cartilaginous septa was undertaken by perivascular cells and multinucleated chondroclasts. Resorption of the calcified cartilage was restricted to the region of ruffled border of the chondroclast. Growth along the metaphyseal side of the epiphyseal center of ossification was different from that along the articular surface. As the secondary center expanded toward the metaphyseal side, many vascular buds penetrated unmineralized cartilaginous septa and invaded viable chondrocytes. Many hypertrophied chondrocytes bodering the metaphyseal side of bone center remained viable after they became embedded in mineralized cartilaginous septa. This result suggested that the hypertrophied.

• 한국자기공명학회논문지
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• 제16권1호
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• pp.22-33
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• 2012

Tid1, belonging to the Hsp40/DnaJ family of proteins, functions as a cochaperone of cytosolic and mitochondrial Hsp70 proteins. In particular, the N-terminal J-domain of Tid1 (Tid1-JD) constitutes the major binding sites for proteinprotein interactions with client proteins, including p53, as well as its partner chaperone, Hsp70. In the present study, soluble, recombinant protein of Tid1-JD could be obtained by using the pCold vector system, and backbone NMR assignments were completed using the isotope $[^{13}C/^{15}N]$-enriched protein. Far-UV CD result implied that Tid1-JD is an ${\alpha}$-helical protein and the secondary structure determined using chemical shift data sets indentified four ${\alpha}$-helices with a loop region containing the HPD (conserved tripeptide of His, Pro and Asp) motif. Additionally, NMR spectra under different conditions implied that the HPD motif, which is a critical region for protein-protein interactions of Tid1-JD, would possess dynamic properties.