NAND 플래시 메모리에서 업데이트 패턴을 고려한 효율적인 페이지 할당 기법

김희태(Hui-Tae KIM),김경석(Kyong-Sok Kim) 한국정보과학회 2009 한국정보과학회 학술발표논문집 Vol.36 No.2B

플래시 메모리는 일반 디스크와 달리 덮어 쓰기가 불가능하다. 대부분의 플래시 메모리 파일 시스템은 데이터를 수정할 때 새로운 공간에 데이터를 쓴 뒤, 기존의 데이터는 무효화(invalid) 시키는 방법(non in-place update)을 사용한다. 가비지 컬렉션(Garbage Collection)은 무효한 페이지를 포함하고 있는 블록을 선택하여 해당 블록내의 유효한(valid) 페이지를 다른 공간에 복사하고, 그 블록을 소거하여 블록 내 모든 페이지를 다시 쓸 수 있는 상태로 변경시킨다. 가비지 컬렉션 연산은 플래시 메모리의 성능에 직접적인 영향을 미치는 요소이다. 본 논문에서는 데이터의 업데이트 패턴에 따라 Hot 데이터와 Cold 데이터로 구분하고 서로 다른 블록에 할당함으로서 가비지 컬렉션을 수행할 때 발생하는 페이지의 복사 횟수를 최소화하여 가비지 컬렉션 비용을 줄이는 효율적인 페이지를 할당 기법을 제안한다. 제안하는 기법은 임베디드 보드에서 플래시 전용 파일 시스템인 YAFFS를 수정하여 구현하였다. 성능 평가 결과 기존의 YAFFS 보다 가비지 컬렉션 연산 중 발생하는 유효 페이지 복사 횟수를 줄여 성능 향상이 나타남을 확인할 수 있었다.

Profiling of remote skeletal muscle gene changes resulting from stimulation of atopic dermatitis disease in NC/Nga mouse model

Lee, Donghee,Seo, Yelim,Kim, Young-Won,Kim, Seongtae,Choi, Jeongyoon,Moon, Sung-Hee,Bae, Hyemi,Kim, Hui-sok,Kim, Hangyeol,Kim, Jae-Hyun,Kim, Tae-Young,Kim, Eunho,Yim, Suemin,Lim, Inja,Bang, Hyoweon,Ki The Korean Society of Pharmacology 2019 The Korean Journal of Physiology & Pharmacology Vol.23 No.5

Although atopic dermatitis (AD) is known to be a representative skin disorder, it also affects the systemic immune response. In a recent study, myoblasts were shown to be involved in the immune regulation, but the roles of muscle cells in AD are poorly understood. We aimed to identify the relationship between mitochondria and atopy by genome-wide analysis of skeletal muscles in mice. We induced AD-like symptoms using house dust mite (HDM) extract in NC/Nga mice. The transcriptional profiles of the untreated group and HDM-induced AD-like group were analyzed and compared using microarray, differentially expressed gene and functional pathway analyses, and protein interaction network construction. Our microarray analysis demonstrated that immune response-, calcium handling-, and mitochondrial metabolism-related genes were differentially expressed. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology pathway analyses, immune response pathways involved in cytokine interaction, nuclear factor-kappa B, and T-cell receptor signaling, calcium handling pathways, and mitochondria metabolism pathways involved in the citrate cycle were significantly upregulated. In protein interaction network analysis, chemokine family-, muscle contraction process-, and immune response-related genes were identified as hub genes with many interactions. In addition, mitochondrial pathways involved in calcium signaling, cardiac muscle contraction, tricarboxylic acid cycle, oxidation-reduction process, and calcium-mediated signaling were significantly stimulated in KEGG and Gene Ontology analyses. Our results provide a comprehensive understanding of the genome-wide transcriptional changes of HDM-induced AD-like symptoms and the indicated genes that could be used as AD clinical biomarkers.

Profiling of remote skeletal muscle gene changes resulting from stimulation of atopic dermatitis disease in NC/Nga mouse model

Donghee Lee,Yelim Seo,Young-Won Kim,Seongtae Kim,Jeongyoon Choi,Sung-Hee Moon,Hyemi Bae,Hui-sok Kim,Hangyeol Kim,Jae-Hyun Kim,Tae-Young Kim,Eunho Kim,Suemin Yim,Inja Lim,Hyoweon Bang,Jung-Ha Kim,Jae-H 대한약리학회 2019 The Korean Journal of Physiology & Pharmacology Vol.23 No.5

Although atopic dermatitis (AD) is known to be a representative skin disorder, it also affects the systemic immune response. In a recent study, myoblasts were shown to be involved in the immune regulation, but the roles of muscle cells in AD are poorly understood. We aimed to identify the relationship between mitochondria and atopy by genome-wide analysis of skeletal muscles in mice. We induced AD-like symptoms using house dust mite (HDM) extract in NC/Nga mice. The transcriptional profiles of the untreated group and HDM-induced AD-like group were analyzed and compared using microarray, differentially expressed gene and functional pathway analyses, and protein interaction network construction. Our microarray analysis demonstrated that immune response-, calcium handling-, and mitochondrial metabolism-related genes were differentially expressed. In the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology pathway analyses, immune response pathways involved in cytokine interaction, nuclear factor-kappa B, and T-cell receptor signaling, calcium handling pathways, and mitochondria metabolism pathways involved in the citrate cycle were significantly upregulated. In protein interaction network analysis, chemokine family-, muscle contraction process-, and immune response-related genes were identified as hub genes with many interactions. In addition, mitochondrial pathways involved in calcium signaling, cardiac muscle contraction, tricarboxylic acid cycle, oxidation-reduction process, and calcium-mediated signaling were significantly stimulated in KEGG and Gene Ontology analyses. Our results provide a comprehensive understanding of the genome-wide transcriptional changes of HDM-induced AD-like symptoms and the indicated genes that could be used as AD clinical biomarkers.

Identification of uricase as a potential target of plant thioredoxin

두희,김성한,남경희,이명석,Ora Son,이석하,천충일 Sookmyung Women's University Research Institute of 2010 여성과 건강 Vol.6 No.1

Identification of uricase as a potential target of plant thioredoxin

두희,김성한,남경희,이명석,Ora Son,이석하,천충일 Sookmyung Women's University Research Institute of 2010 여성과 건강 Vol.6 No.1

A Cytosolic Thioredoxin Acts as a Molecular Chaperone for Peroxisome Matrix Proteins as Well as Antioxidant in Peroxisome

Du, Hui,Kim, Sunghan,Hur, Yoon-Sun,Lee, Myung-Sok,Lee, Suk-Ha,Cheon, Choong-Ill Korean Society for Molecular and Cellular Biology 2015 Molecules and cells Vol.38 No.2

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.

Protective action of 9-hydroxypinoresinol against oxidative damage in brain of mice challenged with kainic acid

Cui, Hui Song,Sok, Dai-Eun,Min, Byung Sun,Kim, Mee Ree Pharmaceutical Society of Great Britain 2007 Journal of pharmacy and pharmacology Vol.59 No.4

한국인의 GSTM1, GSTT1 유전자와 당뇨망막병증의 연관성에 대한 분석

김영휘(Yung Hui Kim),양지명(Jee Myung Yang),장재용(Jae Yong Jang),지영석(Yong Sok Ji) 대한안과학회 2017 대한안과학회지 Vol.58 No.3

목적: 제2형 당뇨병 환자의 Glutathione-S-transferase (GST) 유전자의 변이와 당뇨망막병증 발생의 연관성에 대해 분석하고자 하였다. 대상과 방법: 2013년 1월부터 2015년 11월까지 당뇨망막병증으로 진단받은 환자 131명과 유병기간이 10년 이상인 제2형 당뇨병 환자 중 당뇨망막병증이 발생하지 않은 105명, 그리고 당뇨병이 없는 정상대조군 45명을 대상으로 환자 대조군 연구를 시행하였다. 대상자들의 GSTM1 및 GSTT1 유전자 분석을 위해 사전 동의하에 말초혈액에서 얻어진 혈액샘플로부터 중합효소연쇄반응을 통해 각 유전자의 결손 유무를 분석하였다. 결과: 단변량분석에서 당뇨망막병증이 발생한 군이 발생하지 않은 군보다 제2형 당뇨병의 유병기간이 길었고(p=0.004), HbA1c 값이 더 높았다(p=0.004). GSTT1 유전자결손은 두 군 간의 차이는 없었으나, GSTM1 유전자결손은 당뇨망막병증이 있는 군에서 더 낮은 비율을 보였다(p=0.017). 로지스틱 회귀분석에서 당뇨의 유병기간(p=0.013), 높은 HbA1c (p=0.007), GSTM1 유전자결손이 없는 경우 (p=0.012)가 당뇨망막병증 발생의 위험인자로 분석되었다. 결론: 한국인을 대상으로 시행한 본 연구에서 GSTT1 유전자결손은 당뇨망막병증 발생의 위험성을 증가시키지 않는 반면, GSTM1 유전자결손은 당뇨망막병증 발생의 억제와 연관이 있었다. 향후 이에 대한 대다수의 환자 대조군 연구가 더 필요할 것으로 생각된다. Purpose: To investigate the correlation between Glutathione-S-transferase (GST) genes and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (DM). Methods: In this case-control study, 131 patients who were diagnosed with DR, 105 diabetic patients who did not have DR, and 45 nondiabetic controls were examined from January 2013 to November 2015. To analyze deletion of the GSTT1 and GSTM1 genes, polymerase chain reactions of DNA in a buffy coat from peripheral blood were performed via electrophoresis. Results: There were no statistically significant differences in age, sex, or spherical equivalent between the 236 type 2 diabetic patients and the 45 normal controls (p > 0.05). In both univariate and multivariate analyses, the duration of type 2 DR was longer (p = 0.004, p = 0.013), and HbA1c was higher (p = 0.004, p = 0.007) in the DR group than in the non-DR group. Presence of a GSTM1 deletion is associated with a lower frequency of DR (p = 0.017, p = 0.012). Conclusions: Deletion of the GSTT1 gene is not associated with an increased risk of DR, whereas GSTM1 deletion is associated with a lower risk of DR in patients with type 2 DM in the Korean population. Additional studies with larger sample sizes and different types of GST genes are needed to confirm this study.

Triphenylamine-based tri-anchoring organic dye with enhanced electron lifetime and long-term stability for dye sensitized solar cells

Lee, Yong Hui,Yun, Hyeong Jin,Choi, Sok Kyun,Yang, Yu Seok,Park, Taiho,Ahn, Kwang-Soon,Suresh, Thogiti,Kim, Jae Hong Elsevier 2016 Synthetic metals Vol.217 No.-

<P><B>Abstract</B></P> <P>An organic sensitizer with a multi-anchoring system is a versatile methodology for enhancing the stability and conversion efficiency of dye-sensitized solar cells (DSSCs). Triphenylamine dyes (TPA3T1A∼3A) containing different numbers of anchoring groups are synthesized to determine the correlation between the number of anchoring groups and photovoltaic properties as photosensitizers for DSSCs. The adsorption properties of the dyes on TiO<SUB>2</SUB> electrode were examined by ATR-FT-IR, which show that a mono-anchoring TPA3T1A system adsorbs in monodentate ester-type mode, and the three carboxylic acids in TPA3T3A adsorbs in bidentate bridging mode. The multi-anchoring dye exhibits strong electronic coupling with TiO<SUB>2</SUB>, providing an efficient charge injection rate. Moreover, they increased the electron lifetime significantly by suppressing the charge recombination probability. This synergistic effect enables the fabrication of efficient photovoltaic devices. Furthermore, enhanced long-term stability is also observed in the DSSCs containing a tri-anchoring system compared to the mono- and bi-anchoring systems.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We synthesize tiphenylamine dyes with different number of anchoring groups for DSSCs. </LI> <LI> A tri-anchoring dye (TPA3T3A) shows better electronic coupling with TiO<SUB>2</SUB>. </LI> <LI> TPA3T3A dye exhibits longer electron lifetime with reducing charge recombination. </LI> <LI> A strong adsorption properties of TPA3T3A leads to better long-term stability. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Triphenylamine dyes (TPA3T1A∼3A) containing different numbers of anchoring groups are synthesized to determine the correlation between the number of anchoring groups and photovoltaic properties as photosensitizers for DSSCs. The multi-anchoring dye exhibits strong electronic coupling with TiO<SUB>2</SUB>, providing an efficient charge injection rate and enhanced long-term stability. Moreover, they increased the electron lifetime significantly by suppressing the charge recombination probability. This synergistic effect enables the fabrication of efficient photovoltaic devices.</P> <P>[DISPLAY OMISSION]</P>

수중 센서 네트워크에서 수심, 수온, 염도를 고려한 환경에서 MDS를 이용한 위치인식 연구

정희석,김은찬,양연모,Jung, Hui-Sok,Kim, Eun-Chan,Yang, Yeon-Mo 대한임베디드공학회 2012 대한임베디드공학회논문지 Vol.7 No.4

In these days, there are huge increases of concerning underwater acoustic sensor networks (UWASNs) to explore marine resources and to monitor climate change. To collect information from sensor nodes which are randomly deployed in underwater, Multi-Dimensional Scaling (MDS) based locating methods have been recently introduced, which consider sound speed to be constant in underwater. However, underwater sound speed tends to vary depending on underwater environment factors, such as depth, temperature, and salinity. In this paper, we propose a method considering environment factors, can influence upon sound speed in underwater, and introduce experimental setup which can follow up environmental factors.