• 폴리머
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• 제25권4호
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• pp.587-593
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• 2001

본 연구에서는 red mud(RM)를 0.1, 1, 그리고 5M 의 H$_3PO_4$ 용액으로 화학적 표면처리하여 에폭시/RM 나노복합재료를 제조하였으며, RM 표면의 pH, 표면 산-염기도, 표면적, 그리고 기공도를 이용하여 표면처리에 의한 영향을 분석하였다. 또한, 임계응력 세기인자(K$_{IC}$)를 통하여 제조된 복합재료의 기계적 계면물성을 조사하였다. 실험결과로부터, 표면처리에 의한 RM의 표면은 hydroxyl 등의 산성관능기 그룹의 생성과 금속산화물의 반응으로 인하여 표면 산도가 증가하고, 미세기공 및 중기공 구조가 발달하여 비표면적이 증가되었다. K(IC)를 이용한 RM의 기계적 계면성질은 비표면적이 증가함과 동시에 표면산도가 증가함으로 염기성 매트릭스와의 계면결합력이 증대되어 순수 에폭시와 처리되지 않은 에폭시/RM 복합재료보다 더 우수한 기계적 계면물성을 나타내었다.

• 한국식품영양과학회지
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• 제44권11호
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• pp.1645-1652
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• 2015

해양생물 유래 피부건강 기능성의 소재를 발굴할 목적으로 굴 단백질을 Protamex와 Neutrase로 가수분해 한 후 생성된 굴 가수분해물 펩타이드의 주름 개선 효과를 조사하였다. 굴 가수분해물은 약 7.9%의 유리아미노산을 포함하며 urea, taurine, alanine, glycine 등의 아미노산의 함량이 높았다. 굴 가수분해물은 collagenase 저해 활성을 가지고 있었고, 피부세포인 CCD986sk에 대한 독성은 없었다. 분획물의 수율은 1,000 Da 미만이 40%였으며, 5,000 Da 미만이 60.4%를 차지하였다. 1,000~3,000 Da인 분획물이 항산화 활성, procollagen의 생성능 및 MMP-1 효소 저해 활성이 가장 높았다. 굴 가수분해물과 5,000 Da 미만의 분획물은 주름 개선을 위한 피부건강 기능성 소재로서 화장품 등의 제품에 응용 가능함을 확인하였다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.91-91
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• 2018

Poncirus Fructus (PF) is obtained by drying the trifoliate orange fruit belonging to the Rutaceae family. In our country of medicine, PF has been used as a treatment of indigestion, allergy and inflammation. But Mechanism and medical data for PF is insignificant. Recently, the effect of the study PF of biological activity was reported, such as anti- thrombosis, anti-bacteria, anti-virus, anti- allergic. We investigated that the effect of PF on anti-inflammatory in murine macrophage-like cell line Raw264.7 cells. Our results show that the expression level of Nitric Oxide (NO) and Matrix-metallopeptidase-9 (MMP-9) significantly decreased. Moreover, to determine the expression level of pro-inflammatory cytokines such as Tumor Necrosis Factor ($TNF-{\alpha}$) and Interleukin-6 (IL-6) and the phosphorylation pattern of signaling molecules of mitogen-activated protein kinase (MAPK) family, we performed ELISA and westren blot in Raw264.7 cells. In addition, nuclear factor-kappa B ($NF-{\kappa}B$) pathway was confirmed. PF extract inhibited the production of $TNF-{\alpha}$ and IL-6. The extract suppressed the phosphorylation of ERK1/2, JNK, and p38 MAPK, and the nuclear translocation of $NF-{\kappa}B$ p65 in activated cells. Our results suggest that PF can be used as a potential therapeutic agent or functional food to relieve inflammation.

• Journal of Periodontal and Implant Science
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• 제32권1호
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• pp.235-247
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• 2002

The aim of this study was to evaluate the effects of chitosan coating on the attachment, proliferation, functional and morphological change of human gingival fibroblasts. Primary culture of human gingival fibroblasts were grown in Dulbecco's modified Eagle's medium with 10% fetal bovine serum and 1% antibiotics. In experimental group, cells were inoculated in the multiwell plates coated with chitosan in concentration of 0.02, 0.2, and 2 mg/ml. Cell counting and MTT assay were done after 0.5, 1.5, 3, 6 and 24 hours of incubation to evaluate the cell attachment, and then after 2 and 7 days of culture to evaluate the cell proliferation. The alkaline phosphatase activity was measured after 4 and 7 days of culture and the ability to produce mineralized nodules was evaluated after 21 days of culture. The results were as follows : The morphology of cells on the chitosan-coated well was round or spheric. Round cells were aggregated since 6 hours of culture and showed nodule-like appearance after 24 hours of culture and did not achieved confluency at 7 days. The attachment of gingival fibroblasts was inhibited by chitosan coating with a tendency of dose dependent pattern. But, cellular activity of unit cell was higher than control. The proliferation of gingival fibroblasts was inhibited by chitosan coating at 2 mg/ml(P<0.01), while the cell proliferation at 0.02, 0.2 $mg/m{\ell}$ was comparable to the control well. Total alkaline phosphatase activity was inhibited by chitosan coating and decreased in the course of time. While ALP activity of unit cell was the highest at 2mg/ml after 4 days of culture. Finally, gingival fibroblasts produced the mineralized nodule at 2 mg/ml. In summary, the attachment, proliferation, and alkaline phosphatase activity of gingival fibroblasts were influenced differently by the concentration of coated chitosan. From this study, it could be used as the matrix of tissue engineering for gingiva without inhibition on proliferation of gingival fibroblasts using chitosan at the optimal concentration (0.02mg/ml).

• 한국조리학회지
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• 제23권7호
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• pp.42-49
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• 2017

This study was conducted to determine the nutritional value of domestic cherry tomato varieties (Summerking, Qutiquti, and Minichal). The levels of amino acids, amino acid derivatives, and ${\gamma}-aminobutyric-acid$ (GABA) were analyzed using ion chromatography. In domestic cherry tomatoes, eighteen free amino acids were found including L-glutamic acid (L-Glu), L-glutamine (L-Gln), and L-aspartic acid (L-Asp). L-Glu was the most abundant amino acid, ranging from 1,533.17 mg/100 g to 1,920.65 mg/100 g (dry weight). The next abundant amino acids were L-Gln, ranging from 784.68 mg/100 g to 1,164.36 mg/100 g and L-Asp, ranging from 320.73 mg/100 g to 387.22 mg/100 g. Domestic cherry tomatoes contained eight essential amino acids except tryptophan and the total essential amino acid content was 297.30~432.43 mg/100 g (dry weight), which was 8.92~10.61% of total free amino acid. Several amino acid derivatives were found: L-carnitine (L-Car), hydroxylysine (Hyl), o-phosphoethanolamine (o-Pea), phosphoserine (p-Ser), ${\beta}-alanine$ (${\beta}-Ala$), N-methyl-histidine (Me-His), ethanolamine ($EtNH_2$), and L-citrulline (L-Cit). L-Car, transporting long-chain fatty acid into mitocondrial matrix, was the most abundant amino acid derivative in all domestic cherry tomatoes. A high level of GABA (313.18~638.57 mg/100 g), known as a neurotransmitter, was also found in all three domestic cherry tomatoes. These results revealed that domestic cherry tomatoes have a good balance of nutrient and bioactive compounds. Therefore, cherry tomatoes can be used as a functional food material.

• 지구물리와물리탐사
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• 제10권2호
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• pp.147-153
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• 2007

CG (conjugate gradient) 법은 선형 연립방정식을 반복적으로 푸는 가장 효율적인 해법 중 하나이고, 또한 비선형 최소자승문제에도 적용할 수 있다. 자기지전류(MT) 역산 문제를 풀 때에는 최소자승문제의 목적함수 자체의 최소화에 직접 CG 법을 적용하거나, Gauss-Newton 법에 기초한 반복역산의 각 반복단계에서 모형의 변화량 계산에 CG 법을 이용할 수 있다. CG 법을 적용할 경우, 임의의 벡터에 대한 감도행렬의 영향 및 그 전치행렬의 전치행렬의 영향을 감도행렬을 직접 구하지 않고 계산할 수 있다는 장점이 있기 때문에 감도행렬의 계산 규모가 방대한 3차원 역산 문제에서 계산시간을 월등히 줄일 수 있다.

• Elastomers and Composites
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• 제44권3호
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• pp.232-243
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• 2009

근래 고성능 친환경 타이어의 개발요구에 의하여 경제성(낮은 회전 저항)과 안전성(wet traction) 및 내마모성면에서 균형있는 특성을 가지는 타이어 트레드 고무의 합성 제조 기술이 중요하게 대두된다. 이를 위하여 다양한 기능성 용액중합 SBR의 개발과 함께 고무/충전제 간의 상호작용 증진 기술이 학술적으로나 산업적으로 활용되고 있다. 본 고에서는 기존의 카본블랙 고무와 함께 최근 green tire로서 각광 받는 실리카 충전 고무에서 충전제와 상호반응이 가능한 화학적 변성 SBR과 커플링제를 이용한 고성능 타이어 트레드 고무의 합성 제조 기술에 대하여 최근 연구 방향과 함께 작용 메카니즘에 대하여 고찰하였다.

• International Journal of Oral Biology
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• 제39권2호
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• pp.121-128
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• 2014

Sambucus sieboldiana (SS) is a member of the family Caprifoliaceae and has been recommended as a functional material because of its several bioactivities. Although numerous literatures are available on the pharmacological and biological activities, the biological activity of SS in bone regeneration process has not yet been well-defined. Therefore, in this study, the effect of SS was investigated in the proliferation and differentiation of MC3T3-E1 osteoblastic cell line. The treatment of SS did not significantly affect the cell proliferation in MC3T3-E1 cells. SS significantly accelerated the mineralization and significantly increased the expression of alkaline phosphatase (ALP) and osteocalcin (OC) mRNAs, compared to the control, in the differentiation of MC3T3-E1 cells. SS significantly accelerated the decrease of osteonectin (ON) mRNA expression as compared with the control in a time-dependent manner in the differentiation of MC3T3-E1 cells. These results suggest that the SS facilitate the osteoblast differentiation and mineralization in MC3T3-E1 osteoblastic cells. Therefore, there may be potential properties for development and clinical application of bone regeneration materials.

• Molecules and Cells
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• 제38권2호
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• pp.187-194
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• 2015

Thioredoxin (TRX) is a disulfide reductase present ubiquitously in all taxa and plays an important role as a regulator of cellular redox state. Recently, a redox-independent, chaperone function has also been reported for some thioredoxins. We previously identified nodulin-35, the subunit of soybean uricase, as an interacting target of a cytosolic soybean thioredoxin, GmTRX. Here we report the further characterization of the interaction, which turns out to be independent of the disulfide reductase function and results in the co-localization of GmTRX and nodulin-35 in peroxisomes, suggesting a possible function of GmTRX in peroxisomes. In addition, the chaperone function of GmTRX was demonstrated in in vitro molecular chaperone activity assays including the thermal denaturation assay and malate dehydrogenase aggregation assay. Our results demonstrate that the target of GmTRX is not only confined to the nodulin-35, but many other peroxisomal proteins, including catalase (AtCAT), transthyretin-like protein 1 (AtTTL1), and acyl-coenzyme A oxidase 4 (AtACX4), also interact with the GmTRX. Together with an increased uricase activity of nodulin-35 and reduced ROS accumulation observed in the presence of GmTRX in our results, especially under heat shock and oxidative stress conditions, it appears that GmTRX represents a novel thioredoxin that is co-localized to the peroxisomes, possibly providing functional integrity to peroxisomal proteins.

• 한국통신학회논문지
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• 제32권9A호
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• pp.931-939
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• 2007

본 논문은 SMDL (Sogang Machine Description Language)을 이용한 DSP 프로세서용 인스트럭션 셋 시뮬레이터 자동 생성기 시스템의 설계에 관해 기술한다. SMDL은 DSP 어플리케이션에 최적화된 아키텍처를 포함한 임베디드 코어의 효율적 기술을 위한 머신 기술 언어로서, 구현된 인스트럭션 셋 시뮬레이터 자동 생성 시스템은 타겟 ASIP의 SMDL 기술을 입력으로 하여 인스트럭션들의 파이프라인 스테이지 별 행위 정보를 분석한 후 cycle-accurate 인스트럭션 셋 시뮬레이터를 C++ 파일로 자동 생성한다. 구현된 자동 생성 시스템의 검증을 위해 ARM9E-S, ADSP-TS20x와 TMS320C2x 아키텍처들을 SMDL로 기술하여 시뮬레이터들을 자동 생성하였으며, 생성된 시뮬레이터들을 이용하여 $4{\times}4$ 매트릭스 곱셈, 16비트 IIR 필터, 32비트 곱셈, 그리고 FFT에 연산에 대한 시뮬레이션을 수행하였다. 결과 생성된 시뮬레이터의 정확한 동작을 확인하였다.