• BMB Reports
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• 제50권4호
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• pp.160-161
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• 2017

Proper maintenance of biological components is crucial for longevity and healthy aging. Although the role of homeostatic maintenance systems for DNA and protein in longevity is established, it remains largely unknown for RNA. In our recent work, we show that nonsense-mediated mRNA decay (NMD) promotes longevity in the roundworm C. elegans by enhancing RNA quality control. We find that the activity of NMD decreases during aging, raising the possibility that RNA quality declines in old animals. We then show that key components of NMD complex are required for prolonged lifespan in C. elegans. In addition, animals with reduced insulin/insulin-like growth factor-1 (IGF-1) signaling (IIS), a representative longevity model, display increased NMD activity. Thus, up-regulation of NMD appears to play crucial roles in longevity conferred by reduced IIS via enhancing mRNA quality control. As both IIS and NMD pathways are evolutionarily conserved, mammals including humans may be equipped with similar RNA quality control systems to achieve longevity.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1896-1898
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• 2002

In this paper, to developing thermally and mechanically upgraded ones, we dismounted pole transformers used in the fields for over 13 years and conducted aged oil analysis. Also, when the cellulose and aramid papers in test cell were aging with oil at $130^{\circ}C$ for 3000 hours, with the testing period cellulose paper deteriorated more rapidly than the others. For example dielectric strength and dissipation factor of papers deteriorated with aging time. For evaluation of thermal aging characteristics, a mineral oil-immersed transformer was constructed with hybrid insulation system comprised of aramid paper and cellulose insulation. A Hybrid system has economic advantages. Cellulose materials are confined to cooler regions of the transformer winding. And aramid papers are served to insulate contact parts of hot conductors.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권2호
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• pp.139-144
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• 2013

Negative bias temperature instability (NBTI) has become a major factor determining circuit reliability. The effect of the NBTI on the circuit performance depends on the duty cycle which represents the stress and recovery conditions of each device in a circuit. In this paper, we propose an analytical model to perform more accurate duty cycle estimation at the gate-level. The proposed model allows accurate (average error rate: 3%) computation of the duty cycle without the need for expensive transistor-level simulations Furthermore, our model estimates the waveforms at each node, allowing various aging effects to be applied for a reliable gate-level circuit aging analysis framework.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.86-89
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• 2004

Recently polymer arresters are being used widely but we don't have appropriate long term characteristics test methods. Therefore we need to develop special test facility to evaluate long term reliability of polymer arresters. It's polymeric housing can be degraded by environmental stress and the interface between housing and inner module can be affected by moisture absorption. This moisture absorption can cause leakage current and tracking in the interface. We developed multi stress accelerated ageing test facility to simulate field conditions including UV, temperature, humidity, voltage, salt fog and rain. In addition, we carried out field exposure test at the outdoor test yard and characteristics analysis of field operated specimens to evaluate accelerating factor of this accelerated aging test.

• Journal of Ginseng Research
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• 제45권3호
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• pp.408-419
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• 2021

Background: The decreased renal function is known to be associated with biological aging, of which the main pathological features are chronic inflammation and renal interstitial fibrosis. In previous studies, we reported that total saponins from Panax japonicus (SPJs) can availably protect acute myocardial ischemia. We proposed that SPJs might have similar protective effects for aging-associated renal interstitial fibrosis. Thus, in the present study, we evaluated the overall effect of SPJs on renal fibrosis. Methods: Sprague-Dawley (SD) aging rats were given SPJs by gavage beginning from 18 months old, at 10 mg/kg/d and 60 mg/kg/d, up to 24 months old. After the experiment, changes in morphology, function and fibrosis of their kidneys were detected. The levels of serum uric acid (UA), β2-microglobulin (β2-MG) and cystatin C (Cys C) were assayed with ELISA kits. The levels of extracellular matrix (ECM), matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), inflammatory factors and changes of oxidative stress parameters were examined. Results: After SPJs treatment, SD rats showed significantly histopathological changes in kidneys accompanied by decreased renal fibrosis and increased renal function; As compared with those in 3-month group, the levels of serum UA, Cys C and β2-MG in 24-month group were significantly increased (p < 0.05). Compared with those in the 24-month group, the levels of serum UA, Cys C and β2-MG in the SPJ-H group were significantly decreased. While ECM was reduced and the levels of MMP-2 and MMP-9 were increased, the levels of TIMP-1, TIMP-2 and transforming growth factor-β1 (TGF-β1)/Smad signaling were decreased; the expression level of phosphorylated nuclear factor kappa-B (NF-κB) was down-regulated with reduced inflammatory factors; meanwhile, the expression of nuclear factor erythroid 2-related factor 2-antioxidant response element (Nrf2-ARE) signaling was aggrandized. Conclusion: These results suggest that SPJs treatment can improve age-associated renal fibrosis by inhibiting TGF-β1/Smad, NFκB signaling pathways and activating Nrf2-ARE signaling pathways and that SPJs can be a potentially valuable anti-renal fibrosis drug.

• 패션비즈니스
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• 제18권6호
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• pp.1-18
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• 2014

The purpose of this study is to examine the influence of sociocultural attitudes toward appearance and narcissism on body stress. Questionnaires are being administered to 206 women in their 20's-50's living in Deagu and Kyunbook province. The Frequency, factor analysis, reliability analysis, correlation analysis, regression analysis, ANOVA, and Duncan-test are used for data analysis. Sociocultural attitudes toward appearance are categorized into media appearance internalization and social recognition of appearance. Narcissism factors are found to be leadership/privilege, ostentation, and superiority. Body stress is categorized into 4 factors: weight stress, skin aging stress, body dissatisfaction, and hair stress. Sociocultural attitudes toward appearance was related to the sub-variables of narcissism, and body stress. Media appearance internalization is the sun-variable of sociocultural attitudes toward appearance and has significant effects on weight stress, skin aging stress, and body dissatisfaction sub-variables for body stress. Ostentation, and superiority being the sub-variables of narcissism, have significant effects on weight stress, skin aging stress, body dissatisfaction, and hair stress, the sub-variables for body stress. Ages of women display distinctions between the sub-variables in sociocultural attitudes toward appearance such media appearance internalization, and in narcissism such leadership/privilege, ostentation, superiority, and body stress such weight stress, skin aging stress, body dissatisfaction, and hair stress. This result can be a necessary base line data for adult women's appearance management by examining the influence of the attitude toward the appearance developed from the relationship with people around body stress.

• 한국콘텐츠학회논문지
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• 제11권12호
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• pp.832-843
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• 2011

간호대학생 56명에게 실시한 노인체험복 경험과 소감나누기가 노화불안에 미치는 영향을 파악하였다. 본 연구결과 노인유사체험은 대체로 청년기의 대학생에서 노화불안을 구성하는 4개의 요인 점수를 상승시키지는 않은 것으로 나타났으나 늙으면 주위의 친구들이 사라질까 두렵다는 항목에서 유일하게 노화불안 정도가 상승하였다. 체험 후의 소감나누기 활동은 노인에 대한 두려움 요인의 전체 점수와, 노인들과 어울리기를 좋아한다는 항목과 나이가 많은 노인들을 위해 무엇인가 하는 것을 좋아한다는 항목에서 노화불안 감소를 보여 노화불안 완화에 긍정적인 효과가 있음을 알 수 있었다.

• Journal of Pharmaceutical Investigation
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• 제13권1호
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• pp.1-9
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• 1983

The effect of humidity on crystallization and polymorphic transformation of hydrous aluminum oxide under various humidity at $37^{\circ}$ was examined by means of X-ray diffraction, scanning electron micrograph, IR spectra and DTA. The humidity was an important factor influencing crystallization of hydrous aluminum oxide. The growth or crystal was strongly accelerated by humidity. The aging process is assumed that it is composed of two seperate steps, an increase of the diffraction around $36{\sim}42^{\circ}$, and an appearance and its development of the peak at $18{\sim}20^{\circ}$ of $2{\theta}$ value. The former is considered to be nucleation and the latter correspond to the growth period on crystallization. The crystalline form of aging products was various depending on the degree of humidity, directly it leads to the eventual formation of bayerite in more than 72%, $b{\"{o}}hmite$ in 50% and resembled to Nordstandite in 0% relative humidity, respectively but once formed, it was mostly stable in each surroundings and does not transform to the other more stable form in solid state even after aging for five years. The mechanism responsible for aging is further polymerization process of six-membered rings by deprotonation-dehydration reaction in which positively charged polynuclear hydroxy aluminum complexes formed in the presence of moisture are joined at their edges by double hydroxide bridges.

• The Journal of Advanced Prosthodontics
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• 제9권5호
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• pp.364-370
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• 2017

PURPOSE. To explore the influence of different surface conditionings on surface changes and the influence of surface treatments and aging on the bond strengths of composites to non-aged and aged resin nanoceramics. MATERIALS AND METHODS. Rectangular-shaped non-aged and aged (5000 thermocycles) resin nanoceramic specimens (Lava Ultimate) (n=63, each) were divided into 3 groups according to surface treatments (untreated, air abrasion, or silica coating) (n=21). The surface roughness was measured and scanning electron microscopy was used to examine one specimen from each group. Afterwards, the specimens were repaired with a composite resin (Filtek Z550) and half were sent for aging (5000 thermocycles, n=10, each). Shear bond strengths and failure types were evaluated. Roughness and bond strength were investigated by two- and three-way analysis of variance, respectively. The correlation between the roughness and bond strength was investigated by Pearson's correlation test. RESULTS. Surface-treated samples had higher roughness compared with the untreated specimens (P=.000). For the non-aged resin nanoceramic groups, aging was a significant factor for bond strength; for the aged resin nanoceramic groups, surface treatment and aging were significant factors. The failures were mostly adhesive after thermal cycling, except in the non-aged untreated group and the aged air-abraded group, which had mostly mixed failures. Roughness and bond strength were positively correlated (P=.003). CONCLUSION. Surface treatment is not required for the repair of non-aged resin nanoceramic; for the repair of aged resin nanoceramic restorations, air abrasion is recommended.

• 한국주거학회논문집
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• 제28권1호
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• pp.55-62
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• 2017

As fast-speed of aging in modern society has led to increased concern for aging and health improvement of senior citizens, desire about having healthy living-environment has also increased. Living space for senior citizens has to play role of healing for their body feature as well as decrease in mental and psychological function. Color, as important factor that supplements degenerated sense and coping ability caused by aging, it has been revealed through modern medical science that color is effective for making nervous or calming down when it is delivered to one's nerve through sight. The purpose of this study is to suggest basic resource for color arrangement palette of living space and application method by color therapy to improve seniors' mental health by considering psychological and physical features caused by aging. First, consider psychological and physical feature of seniors and color therapy effect through previous research. Second, extract RGB value after selecting color that is helpful for their mental health by using palette from 'Korea Agency for Technology and Standards'. Third, extract other 3 colors that are similar with extracted color from 'NCS 1950 Color System'. Fourth, deduct palette of 3 color arrangement by using 'NCS Navigator' program. Lastly, extract arrangement palette for them by considering difference in visual features, and then suggest arrangement application for each palette through Computer Simulation.