• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1992년도 추계학술대회
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• pp.105-108
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• 1992

In this paper, we have implemented the telemedicine system which has a color image system and a biosignal processor. The inputted image is acquisited to 512 by 480 color image data. The col looted data is compressed to 1/5 of the original image data by using 1/5 and compression algorithm. A biological signals are inputted by 12 bit A/D converter into the system. In case of using 2400bps modem, a frame full color image data and biological information data needed 10 minutes in transmission.

• 한국재료학회지
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• 제17권1호
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• pp.18-24
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• 2007

Mullite-PSZ composite was prepared by sol-gel method using $Al(sec-OC_4H_9)_3,\;Si(OC_2H_5)_4,\;ZrOCl_2\;8H_2O\;and\;Y_2O_3$. The sinterability ana mechanical properties of powder compacts sintered at $1,650^{\circ}C$ for 4 hrs were investigated for various PSZ contents. In result Al-Si spinel formed at $980^{\circ}C$ from amorphous dried gel, and zirconia as well as mullite crystal formed above $1,200^{\circ}C$. The sintered body was densified to $97{\sim}98%$ except the specimen containing 25vol% PSZ which showed the relative density of about 95% obtained by sintering at $1,650^{\circ}C$ for 4 h. The flexural strength of the sintered body was a maximum value of 290 MPa in 20 vol% PSZ, which was also considerably larger than the value of 200 MPa without PSZ. The value of the fracture toughness increased linearly with increase of PSZ content and showed a maximum value of $4.3MPam^{1/2}$ in 25 vol% PSZ, Namely this value was remarkably larger than the $value(2.6MPam^{1/2})$ of pure mullite without PSZ.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.875-878
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• 1992

In this study, We made use of inter-electrode capacitively coupled type plasma polymerization apparatus in order to make the organic optical thin films. We adopted in Benzen. Vinyl-Pyridine and Styrene, which have optical function in the organic world and manufactured double later. It is examined optics properties by it respectively. At the middle wave length as 550[nm], the transmittance is double layer smaller than one of single layer. The refractive index with wave length is various from 1.55 to 1.65. Then, it is known that measured results are valid because the extinction coefficient(K) is about $10^{-4}$ for variation of refractive index.

• 한국미생물·생명공학회지
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• 제34권4호
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• pp.311-317
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• 2006

식물생육을 촉진하고 고추역병균을 방제하는 다기능 PGPR 균주 Bacillus subtilis AH18 항진균성 cellulase 유전자를 PCR을 이용해 pUC18과 재조합 후 E. coli DH5$\alpha$에 cloning하여 E. coli내에 발현시켰으며, 그 형질전환 균주를 E. coli DH5$\alpha$(pCM 41)이라 명명하였고, 발현된 cellulase를 ce/H라 하였다. E. coli DH5$\alpha$(pCM 41)의 inset 부위는 B. subtilis AH18의 1,582 bp 유전자를 포함하며 cellulase의 유전자는 1,524 bp로 508개의 amino acid가 암호화된 것으로 추정되었고, CMC를 함유한 SDS-PAGE의 방법으로 약 55 kDa의 분자량을 확인하였다. B. subtilis AH18이 가지는 ce/H는 3종의 대표적인 Bacillus spp.들의 cellulase 유전자의 DNA와 아미노산 배열이 98% 이상 유사하였으며, CMC(carboxymethyl-cellulose) 뿐만 아니라, 불용성 섬유소인 Avicel, filter paper(Whatman No. 1) 특히 고추역병균인 Phytophthora capsici의 건조 cell wall도 분해하였다. 또한 colH의 cellulase는 $50^{\circ}C$에서 효소활성이 가장 높았으며, 최적 pH는 pH 6.0이었다. 그리고 $AgNO_3$ 또는 $CoCl_2$ 첨가시 활성이 1.7배, 2배 정도 증가하였고 $HgC1_2$ 첨가시는 활성이 20%까지 떨어졌다. 또한 여러 화학 저해제들 중 Sodium azide 또는 Hydroxy urea는 효소 활성을 증가시켰으며, CDTA 또는 EDIA는 섬유소분해능을 감소시켰다. 이들의 결과는 고추역병균 P. capsici의 생육을 억제하는 B. subtilis AM18의 진균세포벽 용해성 cellula의 효소학적 특성을 구명한 것이라고 할 수 있다.

• Molecules and Cells
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• 제42권11호
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• pp.763-772
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• 2019

Periodontitis is characterized by the loss of periodontal tissues, especially alveolar bone. Common therapies cannot satisfactorily recover lost alveolar bone. Periodontal ligament stem cells (PDLSCs) possess the capacity of self-renewal and multilineage differentiation and are likely to recover lost alveolar bone. In addition, periodontitis is accompanied by hypoxia, and hypoxia-inducible $factor-1{\alpha}$ ($HIF-1{\alpha}$) is a master transcription factor in the response to hypoxia. Thus, we aimed to ascertain how hypoxia affects runt-related transcription factor 2 (RUNX2), a key osteogenic marker, in the osteogenesis of PDLSCs. In this study, we found that hypoxia enhanced the protein expression of $HIF-1{\alpha}$, vascular endothelial growth factor (VEGF), and RUNX2 ex vivo and in situ. VEGF is a target gene of $HIF-1{\alpha}$, and the increased expression of VEGF and RUNX2 proteins was enhanced by cobalt chloride ($CoCl_2$, $100{\mu}mol/L$), an agonist of $HIF-1{\alpha}$, and suppressed by 3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole (YC-1, $10{\mu}mol/L$), an antagonist of $HIF-1{\alpha}$. In addition, VEGF could regulate the expression of RUNX2, as RUNX2 expression was enhanced by human VEGF ($hVEGF_{165}$) and suppressed by VEGF siRNA. In addition, knocking down VEGF could decrease the expression of osteogenesis-related genes, i.e., RUNX2, alkaline phosphatase (ALP), and type I collagen (COL1), and hypoxia could enhance the expression of ALP, COL1, and osteocalcin (OCN) in the early stage of osteogenesis of PDLSCs. Taken together, our results showed that hypoxia could mediate the expression of RUNX2 in PDLSCs via $HIF-1{\alpha}$-induced VEGF and play a positive role in the early stage of osteogenesis of PDLSCs.

• 자연과학논문집
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• 제5권2호
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• pp.63-73
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• 1992

There are many methods of obtaining butadiene described in the literature. In the america it is produced largely from petroleum gases, i.e., by catalytic dehydrogenation of butene of butene-butane mixtures. Butadiene can be recovered from the $C_4$ residue of an olefin plant by distilling off a fraction containing most of the butadiene, catalytically hydrogenating the higher acetylenes to olefins and separating the product from other olefins and isobutane by extraction. Also it can be obtained by cracking naphtha and light oil. Among the individual dienes of commercial importance, 1, 3-butadiene is of first importance. It is used primarily for the production of polymers.In the present paper, it was investigated for a effect of the formation and the growth inhibition of popped corn polymer in butadiene extraction unit. As a result of study, inhibitors, $NaNO_2$ and TBC were good effective for inhibition of the formation and growth in popcorn polymer. The rational formula of popcorn polymer obtained was $(C_4H_6)_x$.

• 대한화장품학회지
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• 제43권3호
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• pp.211-221
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• 2017

돌나물(Sedum sarmentosum)의 기능성과 화장품 소재로서의 특성을 파악하기 위하여 본 연구를 수행하였다. 돌나물을 동결건조하고 분쇄하여 에탄올로 추출한 후 $-20^{\circ}C$ 에 저장하면서 실험에 사용하였다. 돌나물의 에탄올 추출물(SE) 내에 포함된 총폴리페놀화합물(TPC)의 함량은 $27.98{\pm}0.34g/kg$ (건조중량)이었고, epicatechin ($162.14{\pm}5.07mg/kg$), epigallocatechin ($55.99{\pm}2.49mg/kg$) 및 kaempferol ($47.96{\pm}3.02mg/kg$)순으로 많이 함유되어 있는 것으로 분석되었다. SE는 organic radical 소거효과($78.43{\pm}1.08%$)와 금속이온환원능(FRAP value $2.54{\pm}0.12$)을 나타내었다. 또한 SE는 지질과산화 반응의 초기 단계(FTC assay $62.03{\pm}0.38%$)와 최종단계(TBARS assay $55.36{\pm}2.05%$)를 저해하였다. SE (5 mg/mL 건조중량)는 Propionibacterium acne에 대해 항균효과를 나타내었다. SE의 elastase 저해율은 $38.94{\pm}7.09%$이었고, collagenase 저해율은 $78.94{\pm}2.49%$이었다. SE 처리구는 Col3A1 발현양이 증가하였고 collagen 생성율은 대조구보다 $58.11{\pm}1.07%$ 높았다. 0.5% SE가 함유된 수중유적형 크림은 pH 6.88, 밀도 1.47 g/mL이었고, 다양한 온도($-20-45^{\circ}C$)에 4주간 저장하는 동안 크림은 안정한 유화상태를 유지하였다. 따라서 SE는 항균, 항산화, 항노화 활성을 지닌 것으로 사료되었다.

• 한국세라믹학회지
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• 제35권6호
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• pp.583-593
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• 1998

C1A3계 속경성 혼합시멘트에 대한 H3BO3의 첨가에 따른 mortar의 물성과 수화 생성물에 관한 연구를 하였다. H3BO3의 첨가는 응결 시간의 지연과 흐름성의 개선을 가져 왔다. H3BO3의 첨가에 따라 초기 수화 생성물은 monosulfate가 생성 되며 이 생성물이 존재하는 기간도 길어진다. 일단 monosulfate가 생성되면 그후 ettringite로 변화되면서 중간 단계로 gel상의 물질로 변화된다. 초기에 생성되어지는 monosulfate는 mortar의 응결시간과 flow에 영향을 준다.

• 공학논문집
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• 제6권1호
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• pp.97-109
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• 2004

CaO의 첨가량에 따라 $CO_2$가스를 불어넣고 반응시간 변화에 따라 용매로 $C_2 H_5 OH$을 사용하여 에틸렌글리콜을 첨가한 CaO-$C_2 H_5 OH$-$CO_2$계의 기.액반응으로부터 비정질 $CaCO_3$의 합성과 결정구조를 전기전도도, X-선회절 및 주사전자현미경으로 조사하였다. 이 반응에서 900ml의 $C_2 H_5 OH$에 에틸렌글리콜 100ml를 첨가하고 CaO의 양을 10~40g으로 하여 $CO_2$가스를 1$\ell$/min의 유속으로 흡입시켜 얻은 합성분말의 겔형 물질을 신속히 여과, 감압하의 $60^{\circ}C$에서 건조하여 1${\mu}m$이하의 구형 vaterite상과 무정형인 비정질 $CaCO_3$을 얻었다. 그리고 비정질 $CaCO_3$의 일부는 중간생성물로서 연쇄형 calcite로 변화하는 것을 알 수 있었고 침강성 $CaCO_3$의 생성보다 먼저 초기 반응생성물은 비정질 $CaCO_3$이었고 이 경우 생성역역은 pH 7-9의 범위로 상당한 영향을 준다. 또한 비정질 $CaCO_3$은 용액 속에서 불안정하여 용해반응으로 인해서 결국 calcite로 결정화한다. 특히 비정질 $CaCO_3$은 CaO-$C_2 H_5 OH$-$CO_2$계의 반응에 의해서 침강되어 생성되거나 또는 gel상으로 된다.

• Genomics & Informatics
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• 제19권4호
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• pp.42.1-42.17
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• 2021

Salivary gland carcinoma (SGC) is rare cancer, constituting 6% of neoplasms in the head and neck area. The most responsible genes and pathways involved in the pathology of this disorder have not been fully understood. We aimed to identify differentially expressed genes (DEGs), the most critical hub genes, transcription factors, signaling pathways, and biological processes (BPs) associated with the pathogenesis of primary SGC. The mRNA dataset GSE153283 in the Gene Expression Omnibus database was re-analyzed for determining DEGs in cancer tissue of patients with primary SGC compared to the adjacent normal tissue (adjusted p-value < 0.001; |Log2 fold change| > 1). A protein interaction map (PIM) was built, and the main modules within the network were identified and focused on the different pathways and BP analyses. The hub genes of PIM were discovered, and their associated gene regulatory network was built to determine the master regulators involved in the pathogenesis of primary SGC. A total of 137 genes were found to be differentially expressed in primary SGC. The most significant pathways and BPs that were deregulated in the primary disease condition were associated with the cell cycle and fibroblast proliferation procedures. TP53, EGF, FN1, NOTCH1, EZH2, COL1A1, SPP1, CDKN2A, WNT5A, PDGFRB, CCNB1, and H2AFX were demonstrated to be the most critical genes linked with the primary SGC. SPIB, FOXM1, and POLR2A significantly regulate all the hub genes. This study illustrated several hub genes and their master regulators that might be appropriate targets for the therapeutic aims of primary SGC.