• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.749-752
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• 2004

Unlike OLEDs, there is no lifetime testing procedure for TFTs. In this work, we have defined such a procedure and developed a method for the accelerated stress testing of TFT pixel circuits in a-Si AMOLED displays. The acceleration factors derived are based on high current and temperature stress, and can be used to significantly reduce the testing time required to guarantee a 20000-hour display backplane lifespan.

• Korean Journal of Acupuncture
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• v.32 no.1
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• pp.39-39
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• 2015

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2003.04a
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• pp.16-23
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• 2003

인간의 궁극적인 욕망은 뭐니뭐니해도 머니(money)라는 말이 인구에 회자되고 있다. 그래도 인간의 궁극적인 목표는 "건강하게 오래 살고 싶다"는 장수욕망일 것이 분명하다. 이생진 시인은 〈그 노파 〈85세〉라는 시에서 "…/ 아이고 죽어야 하는데/ 무슨 말씀을, 앞으로 10년은 더 사실 건데요/그래서야/하면서 미소짓는 노파의 소녀/…"에서 도 잘 나타나 있다. 인간의 수명은 얼마나 될까\ulcorner 병들지 않고 자연히 죽을 때까지 살수 있는 자연수명 (natural lifespan)은 성장기 연령(20~25세)의 5배라고 하는데, 그렇다면 최소한 100세에서 125세까지는 살 수 있다는 계산이다. (중략)

• Journal of applied mathematics & informatics
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• v.18 no.1_2
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• pp.311-320
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• 2005

Studies in the evolutionary biology of aging require good estimates of the age-dependent mortality rate coefficient (one of the Gompertz parameters). In this paper we introduce an alternative algorithm for estimating this parameter. And we discuss the sensitivity of the estimates to changes in the other model parameters.

• Molecules and Cells
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• v.26 no.5
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• pp.427-435
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• 2008

In this review, we discuss the genes and the related signal pathways that regulate aging and longevity by reviewing recent findings of genetic longevity models in rodents in reference to findings with lower organisms. We also paid special attention to the genes and signals mediating the effects of calorie restriction (CR), a powerful intervention that slows the aging process and extends the lifespan in a range of organisms. An evolutionary view emphasizes the roles of nutrient-sensing and neuroendocrine adaptation to food shortage as the mechanisms underlying the effects of CR. Genetic and non-genetic interventions without CR suggest a role for single or combined hormonal signals that partly mediate the effect of CR. Longevity genes fall into two categories, genes relevant to nutrient-sensing systems and those associated with mitochondrial function or redox regulation. In mammals, disrupted or reduced growth hormone (GH)-insulin-like growth factor (IGF)-1 signaling robustly favors longevity. CR also suppresses the GH-IGF-1 axis, indicating the importance of this signal pathway. Surprisingly, there are very few longevity models to evaluate the enhanced anti-oxidative mechanism, while there is substantial evidence supporting the oxidative stress and damage theory of aging. Either increased or reduced mitochondrial function may extend the lifespan. The role of redox regulation and mitochondrial function in CR remains to be elucidated.

• Biomolecules & Therapeutics
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• v.26 no.6
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• pp.568-575
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• 2018

In order to discover lifespan-extending compounds made from natural resources, activity-guided fractionation of Zingiber officinale Roscoe (Zingiberaceae) ethanol extract was performed using the Caenorhabditis elegans (C. elegans) model system. The compound 6-gingerol was isolated from the most active ethyl acetate soluble fraction, and showed potent longevity-promoting activity. It also elevated the survival rate of worms against stressful environment including thermal, osmotic, and oxidative conditions. Additionally, 6-gingerol elevated the antioxidant enzyme activities of C. elegans, and showed a dose-depend reduction of intracellular reactive oxygen species (ROS) accumulation in worms. Further studies demonstrated that the increased stress tolerance of 6-gingerol-mediated worms could result from the promotion of stress resistance proteins such as heat shock protein (HSP-16.2) and superoxide dismutase (SOD-3). The lipofuscin levels in 6-gingerol treated intestinal worms were decreased in comparison to the control group. No significant 6-gingerol-related changes, including growth, food intake, reproduction, and movement were noted. These results suggest that 6-gingerol exerted longevity-promoting activities independently of these factors and could extend the human lifespan.

• Journal of Ginseng Research
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• v.29 no.2
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• pp.100-106
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• 2005

The number of reporting the effects on ginseng's physiological, pharmacological, and behavioral effects has been increased every year. Major active components of Panax ginseng, are the ginsenosides, which are mainly triterpenoid dammarane derivatives. 3-Nitropropionic acid (3-NP) is blown to induce cellular energy deficit and oxidative stress related neurotoxicity via an irreversible inhibition of the mitochondrial enzyme succinate dehydrogenase (SDH). Intraperitoneal injection of 3-NP produces striatal degeneration. Aged animals was more vulnerable to 3-NP than young animal. We used three different ages of 5-, 8-, and 26-week-old rats. 3-NP alone treatment induced striatal lesion and increased lesion volume with age-dependent manner in 5-, 8-, and 26-week-old rats by $30.2{\pm}5.8$, $v$, and $51.3{\pm}8.4mm^3$, respectively. However, pretreatment of GTS (100 mg/kg/day) before 3-NP reduced striatal lesion in 5-,8-, and 26-week-old rats by $3.15{\pm}6.1$, $8.89{\pm}1.9$, and $27.3{\pm}5.6mm^3$, respectively. Pretreatment of GTS also significantly increased survival rate in 5-week-old rats (3-NP alone: GTS +3-NP = $40.4{\pm}6.3$: $72.5{\pm}9.5\%$) than 8-week-old rats (3-NP alone: GTS + 3-NP : $13.5{\pm}5.2\%$ : $45.1{\pm}3.1\%$). In 26-week-old rats, 3-NP alone treated group died on day 18, whereas GTS +3-NP-treated group prolonged lifespan to 30 days. Thus, pretreatment of GTS before administration of 3-NP extended lifespan in all ages. The present results indicate that aged animals are more vulnerable to 3-NP and GTS pretreatment protected 3-NP-induced striatal damage in different ages of animals.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.3
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• pp.142-149
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• 2013

Among ammunitions which are stored in a war field, the lifespan of propelling gunpowder is affected by storage environment such as storage temperature, humidity, and exposure to sunlight. These are because Nitrocellulose (NC) which is the main component of propelling gunpowder can be naturally disassembled to unstable substances similar with other nitric acid ester. We can't prevent it fundamentally from being disassembled, but to restrain induction of automatic disassembly by decomposition product, a decomposition product ($NO_2$, $NO_3$, and $HNO_3$) and tranquillizer DPA (Diphenylamine), having high reactivity, are added into a propellant. For this, it will decrease the velocity of tranquillizer which can also affect the velocity of producing the decomposition product of NC, storage temperature or humidity of propelling gunpowder is higher, drop of tranquillizer content is much faster. Therefore, to extend storage lifespan of propelling gunpowder, it is really important to control storage temperature or humidity inside the magazine. Hereupon, according to the manufacture of small scale model magazine and the result of performing experiments and measuring variation of inside temperature (storage temperature), using roof types that have a steel slate structure of magazine among ground magazines, this research shows the differences in details.

• Molecules and Cells
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• v.21 no.2
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• pp.261-268
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• 2006

The Drosophila methuselah (mth) mutant has an approximately 35 percent increase in average lifespan, and enhanced resistance to various forms of stress, including starvation, high temperature, and dietary paraquat. To examine the transcriptional regulation of mth, we used luciferase assays employing Drosophila S2 cells. Two positive control elements were found at -542 ~ -272 (PE1) and +28 ~ +217 (PE2), where putative binding sites for transcription factors including Dorsal (Dl) were identified. Cotransfection of a Dl expression plasmid with a mth-luciferase reporter plasmid resulted in decreased reporter activity. PE1 and PE2, the minimal elements for strong promoter activity, were required for maximal repression by Dl protein. The N-terminal Rel homology domain (RHD) of Dl was not sufficient for repression of mth. We demonstrated by chromatin affinity precipitation (ChAP) assays in S2 cells that Dl bound to the putative PE1 binding site. Unexpectedly, semi-quantitative RT-PCR analysis revealed that the level of mth transcripts was reduced in dl flies. However, the in vivo result support the view that mth expression is regulated by dl, since it is well known that Dl functions as both a transcriptional activator and repressor depending on what other transcription factors are present. These findings suggest that both innate immunity and resistance to stress are controlled by Dl protein.

• Molecules and Cells
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• v.37 no.1
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• pp.51-57
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• 2014

NOG1 is a nucleolar GTPase that is critical for 60S ribosome biogenesis. Recently, NOG1 was identified as one of the downstream regulators of target of rapamycin (TOR) in yeast. It is reported that TOR is involved in regulating lifespan and fat storage in Caenorhabditis elegans. Here, we show that the nog1 ortholog (T07A9.9: nog-1) in C. elegans regulates growth, development, lifespan, and fat metabolism. A green fluorescence protein (GFP) promoter assay revealed ubiquitous expression of C. elegans nog-1 from the early embryonic to the adult stage. Furthermore, the GFP-tagged NOG-1 protein is localized to the nucleus, whereas the aberrant NOG-1 protein is concentrated in the nucleolus. Functional studies of NOG-1 in C. elegans further revealed that nog-1 knockdown resulted in smaller broodsize, slower growth, increased life span, and more fat storage. Moreover, nog-1 over-expression resulted in decreased life span. Taken together, our data suggest that nog-1 in C. elegans may be an important player in regulating life span and fat storage via the insulin/IGF pathway.