• Title/Summary/Keyword: aging factor

Search Result 892, Processing Time 0.03 seconds

Longevity regulation by NMD-mediated mRNA quality control

  • Son, Heehwa G.;Lee, Seung-Jae V.
    • BMB Reports
    • /
    • v.50 no.4
    • /
    • pp.160-161
    • /
    • 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.

The Study on Application of Hybrid Insulation System for Thermally Upgraded Distribution pole Transformers (주상변압기 열적 특성 향상을 위한 복합절연 시스템 적용)

  • Lee, B.S.;Song, I.K.;Lee, J.B.;Kim, D.M.;Han, S.O.
    • Proceedings of the KIEE Conference
    • /
    • 2002.07c
    • /
    • pp.1896-1898
    • /
    • 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.

  • PDF

An Accurate Gate-level Stress Estimation for NBTI

  • Han, Sangwoo;Lee, Junho;Kim, Byung-Su;Kim, Juho
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.13 no.2
    • /
    • pp.139-144
    • /
    • 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.

Aging Characteristics of Polymer Lighting Arrester by Multi-Stress Accelerated Aging Test (복합가속열화시험에 의한 폴리머 피뢰기의 경년특성)

  • Song, Hyun-Seok;Lee, Jae-Bong;Jang, Sang-Ok;Han, Yong-Huei;Oh, Jae-Hyoung
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2004.05a
    • /
    • pp.86-89
    • /
    • 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.

  • PDF

Saponins from Panax japonicus ameliorate age-related renal fibrosis by inhibition of inflammation mediated by NF-κB and TGF-β1/Smad signaling and suppression of oxidative stress via activation of Nrf2-ARE signaling

  • Gao, Yan;Yuan, Ding;Gai, Liyue;Wu, Xuelian;Shi, Yue;He, Yumin;Liu, Chaoqi;Zhang, Changcheng;Zhou, Gang;Yuan, Chengfu
    • Journal of Ginseng Research
    • /
    • v.45 no.3
    • /
    • pp.408-419
    • /
    • 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.

The Influence of Sociocultural Attitude toward Appearance and Narcissism on Body Stress

  • Park, Eunhee;Lee, Sangjoo
    • Journal of Fashion Business
    • /
    • v.18 no.6
    • /
    • pp.1-18
    • /
    • 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.

Influence of the Senior Simulation Program on Aging Anxiety in Nursing Students (간호대학생이 경험한 노인유사체험이 노화불안에 미치는 영향)

  • Jeong, Hye-Sun;Han, Jong-Sook;Kim, Jung-Hee
    • The Journal of the Korea Contents Association
    • /
    • v.11 no.12
    • /
    • pp.832-843
    • /
    • 2011
  • This quasi-experimental study examined the effect of the a senior simulation program and following group discussion on the anxiety about aging. The senior simulation program did not raise the level of four factors of the anxiety about aging. The item of fear of losing friends when becoming old was the only significant one with increased level of anxiety. Discussion session for sharing the simulation experience revealed a positive effect of decreasing anxiety level in the factor score of fear of old people, the item of liking getting together with elders, and the item of liking to do something for elders. With the help of information technology.

Effect of Humidity on Polymorphic Transformation of Hydrous Aluminum Oxide (알루미나수화물(水和物)의 결정전이(結晶轉移)에 미치는 습도(濕度)의 영향(影響))

  • Rhee, Gye-Ju;Yoo, Byeong-Tae
    • Journal of Pharmaceutical Investigation
    • /
    • v.13 no.1
    • /
    • pp.1-9
    • /
    • 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.

  • PDF

Repair bond strengths of non-aged and aged resin nanoceramics

  • Subasi, Meryem Gulce;Alp, Gulce
    • The Journal of Advanced Prosthodontics
    • /
    • v.9 no.5
    • /
    • pp.364-370
    • /
    • 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.

A Palette of Color Combination Based on Color Therapy for the Elderly (고령자를 고려한 컬러테라피 기반 색채 배색 팔레트)

  • Lee, Eun-Ji;Park, Sung-Jun
    • Journal of the Korean housing association
    • /
    • v.28 no.1
    • /
    • pp.55-62
    • /
    • 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.