• 한국전자통신학회논문지
• /
• 제17권2호
• /
• pp.367-374
• /
• 2022

그래프 노드상에서 발생하는 그래프 신호의 일부를 선택해서 만든 샘플링 신호로부터 원신호를 복원하기 위해, 복원오차를 최소화하기 위한 최적의 샘플링 집합을 선택하는 알고리즘에 관해 연구한다. 복잡도 개선을 위해 복원오차를 직접적으로 최소화하는 대신에, 복원오차의 상한값을 비용함수로 사용하고, QR분해 적용을 통해 발생하는 상삼각행렬의 대각선상에 위치하는 값으로 샘플링을 결정할 수 있게 하는, 저 복잡도를 갖는 반복적 탐욕알고리즘을 제안한다. 기존의 샘플링 선택 방법과 비교하여, 제안 알고리즘이 복원 성능 저하를 평균 5%미만으로 유지하면서, 약 3.5배 빠른 실행시간을 보임을 다양한 그래프 상황에서 실험을 통해 확인한다.

• Genomics & Informatics
• /
• 제21권1호
• /
• pp.6.1-6.8
• /
• 2023

Glaucoma is the second leading cause of irreversible blindness, and primary open-angle glaucoma (POAG) is the most common type. Due to inadequate diagnosis, treatment is often not administered until symptoms occur. Hence, approaches enabling earlier prediction or diagnosis of POAG are necessary. We aimed to identify novel drugs for glaucoma through bioinformatics and network analysis. Data from 36 samples, obtained from the trabecular meshwork of healthy individuals and patients with POAG, were acquired from a dataset. Next, differentially expressed genes (DEGs) were identified to construct a protein-protein interaction (PPI) network. In both stages, the genes were enriched by studying the critical biological processes and pathways related to POAG. Finally, a drug-gene network was constructed, and novel drugs for POAG treatment were proposed. Genes with p < 0.01 and |log fold change| > 0.3 (1,350 genes) were considered DEGs and utilized to construct a PPI network. Enrichment analysis yielded several key pathways that were upregulated or downregulated. For example, extracellular matrix organization, the immune system, neutrophil degranulation, and cytokine signaling were upregulated among immune pathways, while signal transduction, the immune system, extracellular matrix organization, and receptor tyrosine kinase signaling were downregulated. Finally, novel drugs including metformin hydrochloride, ixazomib citrate, and cisplatin warrant further analysis of their potential roles in POAG treatment. The candidate drugs identified in this computational analysis require in vitro and in vivo validation to confirm their effectiveness in POAG treatment. This may pave the way for understanding life-threatening disorders such as cancer.

• Advances in nano research
• /
• 제15권3호
• /
• pp.253-261
• /
• 2023

This study investigates the application of nano-composite materials in physical education, specifically focusing on improving the performance of sports hall flooring. The research centers on carbon nanotube reinforced polyvinyl chloride (PVC) composites, which offer enhanced mechanical properties and durability. The incorporation of carbon nanotubes as reinforcements in the PVC matrix provides notable benefits, including increased strength, improved thermal stability, electrical conductivity, and resistance to fatigue. The key parameters examined in this study are the weight percentage of carbon nanotubes and the temperature during the fabrication process. Through careful analysis, it is found that higher weight percentages of carbon nanotubes contribute to a more uniform dispersion within the PVC matrix, resulting in improved mechanical properties. Additionally, higher fabrication temperatures aid in repairing macroscopic defects, leading to enhanced overall performance. The findings of this study indicate that the utilization of carbon nanotube reinforced PVC composites can significantly enhance the strength and durability of sports hall flooring. By employing these advanced materials, the safety and suitability of physical education environments can be greatly improved. Furthermore, the insights gained from this research can contribute to the optimization of composite material design and fabrication techniques, not only in the field of physical education but also in various industries where composite materials find applications.

• Biomolecules & Therapeutics
• /
• 제32권2호
• /
• pp.240-248
• /
• 2024

We observed that treatment with dimethyl α-ketoglutarate (DMK) increased the amount of intracellular α-ketoglutarate significantly more than that of α-ketoglutarate in HaCaT cells. DMK also increased the level of intracellular 4-hydroxyproline and promoted the production of collagen in HaCaT cells. In addition, DMK decreased the production of collagenase and elastase and down-regulated the expression of selected matrix metalloproteinases (MMPs), such as MMP-1, MMP-9, MMP-10, and MMP-12, via transcriptional inhibition. The inhibition of MMPs by DMK was mediated by the suppression of the IL-1 signaling cascade, leading to the attenuation of ERK1/2 phosphorylation and AP-1 transactivation. Our study results illustrate that DMK, an alkylated derivative of α-ketoglutarate, increased the level of 4-hydroxyproline, promoted the production of collagen, and inhibited the expression of selected MMPs by affecting the IL-1 cascade and AP-1 transactivation in HaCaT cells. The results suggest that DMK might be useful as an anti-wrinkle ingredient.

• Bulletin of the Korean Chemical Society
• /
• 제33권3호
• /
• pp.790-794
• /
• 2012

Trace metal ions such as $Cd^{2+}$, $Ni^{2+}$, and $Zn^{2+}$ in a highly saline sample were subjected to on-line complexation with 4-(2-thiazolylazo) resorcinol (TAR) dissolved in a background electrolyte (BGE) under transient isotachophoresis (TITP) conditions. A long plug of the saline sample, containing the trace metal ions but devoid of TAR, was injected into a coated capillary filled with a BGE composed of 150 mM 2-(cyclohexylamino) ethanesulfonic acid (CHES) and 110 mM triethylamine (TEA) at pH 9.7. Since the electrophoretic mobility of TAR fell between the mobilities of the anionic leading electrolyte ($Cl^-$ in the sample) and the anionic terminating background electrolyte ($CHES^-$), a highly concentrated zone of TAR from the BGE was formed at the rear of the sample matrix and then the metal cations toward the cathode were swept by isotachophoretically assisted on-line complexation (IAOC) between the metal ions and the isotachophoretically stacked TAR. As a result, anionic metal-TAR complexes were formed efficiently, which satisfy the TITP conditions between $Cl^-$ and $CHES^-$. The enrichment factors of metal ions including $Cd^{2+}$ were up to 780-fold compared to a conventional CZE mode using absorbance detection. The detection limits were 17 nM, 15 nM, and 27 nM for $Ni^{2+}$, $Zn^{2+}$, and $Cd^{2+}$ in a 250 mM NaCl matrix, respectively. Our method was successfully applied to the analysis of urine samples without desalting.

• 한국자원식물학회지
• /
• 제21권1호
• /
• pp.96-102
• /
• 2008

Nelumbo nucifera Gaertn.(family Nymphaeaceae) has been used for summer heat syndrome as home remedy in Japan, China and Korea. Although whole plant parts are edible, root is commonly consumed. It has been reported that rhizome extract showed anti-diabetic and anti-inflammatory effects. However, in spite of usefulness for treatment of various diseases, the effect of Nelumbo nucifera rhizome(NNR) on proliferation, migration and matrix degrading enzymes-matrix metalloproteinsases(MMPs), the expression of which degrades extracellular matrix(ECM) leading to metastasis, has not been fully elucidated. We examined the effect of hot water extract of NNR on the proliferation, migration and secretion of MMP-2 and MMP-9 in rat smooth muscle cells(rSMC), epidermoid cancer cells(A431) and breast cancer cells(MDA-MB-231). The proliferation assay was carried out using MTT assay, the principle of which depends upon the conversion of MTT by mitochondrial dehydrogensases of viable cells to formazan crystals. The effect of NNR on migration of cells was examined using wound healing assay. Our results showed that there was inhibition in the proliferation, migration and expression of MMP-2 and MMP-9 in dose dependent fashion in all the cells used. Thus, we concluded that NNR could be used as traditional medicine in the treatment of various diseases where proliferation, migration and MMPs' expression plays a pathological role like in restenosis and metastasis.

• The Korean Journal of Physiology and Pharmacology
• /
• 제19권6호
• /
• pp.485-489
• /
• 2015

Diabetic nephropathy (DN) is the leading cause of end-stage failure of the kidney, but the efficacy of currently available strategies for the prevention of DN remains unsatisfactory. In this study, we investigated the effects of free anthraquinones (FARs) extract, which was extracted from the rhubarb and purified by macroporous resin DM130 with gradient mixtures of ethanol/water as the lelution solvents, in high glucose-cultured glomerular mesangial cells (MCs). The cell proliferation was determined by CCK-8 assay, the levels of TGF-${\beta}1$, CTGF, ColIV and FN proteins in the supernatant of MCs were measured by ELISA assays, and the mRNA levels of these four genes were detected by RT-PCR. The results showed that the increased proliferation of MCs, the mRNA levels and protein expression of TGF-${\beta}1$, CTGF, ColIV and FN induced by high glucose were inhibited after the treatment with the FARs extract. This indicated that FARs extract could inhibit cell proliferation and the expression of main extracellular matrix induced by high glucose in MCs. The FARs extract exhibited potential values for prophylaxis and therapy of DN.

• 건축역사연구
• /
• 제11권3호
• /
• pp.21-34
• /
• 2002

This study is to analyse the transformation process of spatial structure of traditional small city structure in Jeollabuk-Do in the process of modern urbanization between 19th century and the year 2000. The small cities, IM-PI, YONG-AN, YEO-SAN, OK-GOO, GO-SAN, MU-JANG, GUM-MA, GO-BU, which have been local administrative center in CHO-SUN dynasty, have role of local administrative center of subdivision of country-myon, except OK-GOO. The method of this study is to investigate the transformation process of spatial structural elements of with the actual field surveys, the analysis of Gunhyun map made in 1872, land registration maps in 1910s and 2000, and various topological maps. The elements of analysis are the topological site and geographical situation conditions, the urbanized areas, the street systems, the function of streets, the focal points of urban land use, the land use systems, and the location of major facilities such as administration facilities, markets, bus terminals. The analytical point of view and the results are as follows. There is strong relationship between the transformation of internal matrix route system and the growth pattern of urbanized areas, Especially on the contrary to the matrix route with East-West direction which has the role of checking the growth of urbanized area, the South-North direction route acts as the leading line of the growth. The focal points structure of urban land use shows transformation process from the point of central space of administrative district in front of Nae-A, to the access point to administrative district or to the access point to housing and neighborhood commercial area. From the point of functional area structure and major facilities location, line-type commercial area is developed along the line of central axis route and access route to administrative district. Especially direction of the growth of commercial area is strongly connected with the interrelationship between the study area and its neighboring cities. Pattern of commercial district development is varied with the direction of matrix route. That is, commercial district, which shows one side development pattern along the East-West direction route, is developed on both sides of street along the South-North direction route.

• 공업화학
• /
• 제10권2호
• /
• pp.201-205
• /
• 1999

Hydroxypropylmethylcelluloses (HPMC)는 친수성 cellulose 계통의 중합체로서 독성이 적고 가격이 저렴하여 경구용 서방출성 제제에 널리 이용되고 있다. 본 연구에서는 매트릭스로서 HPMC를 이용하여 새로운 서방출성제제인 HPMC/염산슈도에페드린계를 설계하고, 직타법에 의하여 정제를 제조하였으며, 이 팽윤될 수 있는 친수성 약물전달계를 이용하여 약물의 방출에 영향을 주는 여러 인자들이 약물의 방출속도에 미치는 영향에 대하여 조사하였다. 결과로서, HPMC/염산슈도에페드린계에서 매트릭스인 HPMC의 분자량이 클수록, HPMC의 함량이 많을수록 약물의 방출속도가 더 느려짐을 알 수 있었으며, 정제의 경도나 용출시 pH 변화에는 무관한 것으로 나타났다. 특히, 음이온 계면활성제인 sodium laurylsulfate는 HPMC로부터 염산슈도에페드린의 방출속도를 지연시키는데 큰 영향을 미치는 것으로 나타났으며, 이러한 현상은 음이온 계면활성제인 sodium laurylsulfate가 반대의 이온성을 갖는 약물인 염산슈도에페드린과 착물을 형성함으로써 약물의 용해성이 떨어져서 약물방출이 지연되는 것으로 생각된다.

• 한국통신학회논문지
• /
• 제35권11B호
• /
• pp.1704-1709
• /
• 2010

무기체계 시스템 개발에서는 분명히 기술 선도국이 존재하고 무기체계 개발경쟁에서 앞서 있는 것을 부인할 수 없는데, 여기에 더불어 시스템의 설계 정보에 접근이 거의 불기능하다는 것도 현실이다. 따라서 이미 배치되어 운용되고 있는 선도 시스템과 유사한 무기체계 시스템의 개발이 필요한 경우의 개발 방법론이 필요하다. 한 가지 접근 방법으로 기존에 선진국에서 개발된 유사한 시스템을 분석하여 설계 정보로 참조하고, 이를 기반으로 추가적으로 설계 최적화에 대한 노력을 수행하는 것을 제시할 수 있다. 본 연구에서는 설계정보의 접근에 제약이 있는 선진 시스템에 대해 역공학 분석을 수행하여 설계 정보를 추출하여 정리해서 대상시스템의 기반 설계 정보로 활용하고 이 설계 정보들을 DSM 기법을 활용하여 최적화 설계 구조로 개선하는 방법을 제시하였다. 시스템의 설계 예로 유도무기체계 개발에 적용하였다.