• Title/Summary/Keyword: response modification factors

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Immune Disorders and Its Correlation with Gut Microbiome

  • Hwang, Ji-Sun;Im, Chang-Rok;Im, Sin-Hyeog
    • IMMUNE NETWORK
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    • v.12 no.4
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    • pp.129-138
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    • 2012
  • Allergic disorders such as atopic dermatitis and asthma are common hyper-immune disorders in industrialized countries. Along with genetic association, environmental factors and gut microbiota have been suggested as major triggering factors for the development of atopic dermatitis. Numerous studies support the association of hygiene hypothesis in allergic immune disorders that a lack of early childhood exposure to diverse microorganism increases susceptibility to allergic diseases. Among the symbiotic microorganisms (e.g. gut flora or probiotics), probiotics confer health benefits through multiple action mechanisms including modification of immune response in gut associated lymphoid tissue (GALT). Although many human clinical trials and mouse studies demonstrated the beneficial effects of probiotics in diverse immune disorders, this effect is strain specific and needs to apply specific probiotics for specific allergic diseases. Herein, we briefly review the diverse functions and regulation mechanisms of probiotics in diverse disorders.

Damage of Gyeongju 9.12 Earthquakes and Seismic Design Criteria for Nonstructural Elements (경주 9.12지진의 피해 및 비구조요소 내진설계기준)

  • Lee, Su Hyeon;Cho, Tae Gu;Lim, Hwan Taek;Choi, Byong Jeong
    • Journal of the Earthquake Engineering Society of Korea
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    • v.20 no.7_spc
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    • pp.561-567
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    • 2016
  • After the Gyeong-ju 9.12 earthquake, we found the necessity of seismic design of nonstructural element is important to reduce damages in view of properties and economic losses. This study focused on the investigation of damages including both properties and human beings. It was found that most of the damages are leaking of water pipe line, rupture of glasses, spalling of roof finishing, cracks of building, and falling from roof. It was also found that the seismic design force of nonstructural elements is taking account into the natural periods, amplification factors, response modification factors to forsee inelastic behaviors. From this studies, it is recommended that more studies are necessary on the seismic design force of nonstructural element.

Evaluation of Seismic Design Parameters for Nonstructural Components Based on Coupled Structure-Nonstructural 2-DOF System Analysis (구조물-비구조요소 2자유도 결합시스템 해석을 통한 비구조요소 내진설계변수 평가)

  • Bae, Chang Jun;Lee, Cheol-Ho;Jun, Su-Chan
    • Journal of the Earthquake Engineering Society of Korea
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    • v.26 no.3
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    • pp.105-116
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    • 2022
  • Seismic demand on nonstructural components (NSCs) is highly dependent on the coupled behavior of a combined supporting structure-NSC system. Because of the inherent complexities of the problem, many of the affecting factors are inevitably neglected or simplified based on engineering judgments in current seismic design codes. However, a systematic analysis of the key affecting factors should establish reasonable seismic design provisions for NSCs. In this study, an idealized 2-DOF model simulating the coupled structure-NSC system was constructed to analyze the parameters that affect the response of NSCs comprehensively. The analyses were conducted to evaluate the effects of structure-NSC mass ratio, structure, and NSC nonlinearities on the peak component acceleration. Also, the appropriateness of component ductility factor (Rp) given by current codes was discussed based on the required ductility capacity of NSCs. It was observed that the responses of NSCs on the coupled system were significantly affected by the mass ratio, resulting in lower accelerations than the floor spectrum-based response, which neglected the interaction effects. Also, the component amplification factor (ap) in current provisions tended to underestimate the dynamic amplification of NSCs with a mass ratio of less than 15%. The nonlinearity of NSCs decreased the component responses. In some cases, the code-specified Rp caused nonlinear deformation far beyond the ductility capacity of NSCs, and a practically unacceptable level of ductility was required for short-period NSCs to achieve the assigned amount of response reduction.

Deformation Demand of the Precast Concrete Frame Buildings with Ductile Connection in Moderate Seismic Regions (연성적인 접합부를 가진 프리캐스트 콘크리트 골조건물의 변형수요)

  • 서수연;이리형
    • Journal of the Korea Concrete Institute
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    • v.11 no.5
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    • pp.89-98
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    • 1999
  • This paper evaluates nonlinear response characteristics of precast concrete frame buildings. where plastics hinging occurs in the precast connection. Designs were developed for buildings of 5, 10 and 15 stories in hight for moderate seismic risk regions of the U. S. The responses of the buildings were analyzed using DRAIN-2DX and following Nonlinear static analysis procedure of ATC 19. The main variables of the analyses were the strength and stiffness of the connection. Also, for the analysis, the bi-linear response model, developed and inserted into the DRAIN-2DX program by Shan Shi and D. Fouch, was used. With the results of analysis, the deformation demands of the connection of precast concrete frame buildings are proposed by using equal-dissipated energy capacity. It was shown that the strength of the buildings as well as their displacement capacities decreased with the decrease of either the strength or stiffness in the connections. Therefore such changes also require reductions in the response modification factors for such buildings. However, if the precast concrete frame building has plastic hinging in the connection, and has a more ductile connection than the monolithic frame building, then no reduction in R may be necessary. The deformation demand required of the connection to achieve that condition is evaluated and a simple relation is suggested in the paper.

Evaluation of Site-dependent Ductility Factors for Elastic Perfectly Plastic SDOF Systems (토질조건에 따른 탄소성 단자유도 구조물의 연성계수 평가)

  • Kang, Cheol-Kyu;Choi, Byong-Jeong
    • Journal of the Earthquake Engineering Society of Korea
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    • v.8 no.4
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    • pp.11-20
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    • 2004
  • This paper suggests the site-dependent ductility factor which is a key component of response modification factor(R). To compute the ductility factor, a group of 1,860 ground motions recorded from 47 earthquake was considered. Based on the local site conditions at the recording station, ground motions were classified into four groups according to average shear wave velocity. This site classification was consistent with site categories of the UBC(1997), NEHRP(1997) and IBC 2000(1997). Based on the results of regression analysis, a simplified equations were proposed to compute site-dependent ductility factors. The proposed equations were relatively simple and provide a good estimation of mean ductility factors. Based on the proposed equation, ductility factors considering the site conditions can be evaluated in accordance with the present building codes.

Estimation of the vibration fatigue of a linear elastic system based on a desiign sensitivity analysis (설계 만감도 해석을 활용한 선형 시스템 진동내구 평가)

  • Kim, Chan-Jung;Kim, Ku-Sik;Kang, Ho-Young;Jin, Yeo-Hwa;Lee, Bong-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2010.10a
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    • pp.491-496
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    • 2010
  • The direct design modification of problematic component is disallowed in order to sacrifice other major factors such as a stability or a major performance. So, the best design policy is to risvise the immature structural medchanism under the minimal design change as soon as possible. For this paper presents a new design sensitivity analysis based on transmissibility rtio (TR) of response acceleration to find a proper candidate for the minimal design modification. The new sensitivity analysis is based on the fact that the sensitivity of TR over a small design change is inversly proportinal to the magnitude of TR. The theory of proposed design sensitivity analysis is simulated with the variance of TR over a dynamic change. Then, new methodology is appplied for a linear elastic specimen to detect the most sensitive node over a design change using measured accleration data during uni-axial vibration test, The physical verification of the sensitivity method is conducted on the CAE model of a linear elastic specimen by adding concentration mass and the vibration fatigue of the simple specimen is analyzed to estimate the relationship between fatigue behaviors and sensitivity consequences.

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Regulation by Reversible S-Glutathionylation: Molecular Targets Implicated in Inflammatory Diseases

  • Shelton, Melissa D.;Mieyal, John J.
    • Molecules and Cells
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    • v.25 no.3
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    • pp.332-346
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    • 2008
  • S-glutathionylation is a reversible post-translational modification that continues to gain eminence as a redox regulatory mechanism of protein activity and associated cellular functions. Many diverse cellular proteins such as transcription factors, adhesion molecules, enzymes, and cytokines are reported to undergo glutathionylation, although the functional impact has been less well characterized. De-glutathionylation is catalyzed specifically and efficiently by glutaredoxin (GRx, aka thioltransferase), and facile reversibility is critical in determining the physiological relevance of glutathionylation as a means of protein regulation. Thus, studies with cohesive themes addressing both the glutathionylation of proteins and the corresponding impact of GRx are especially useful in advancing understanding. Reactive oxygen species (ROS) and redox regulation are well accepted as playing a role in inflammatory processes, such as leukostasis and the destruction of foreign particles by macrophages. We discuss in this review the current implications of GRx and/or glutathionylation in the inflammatory response and in diseases associated with chronic inflammation, namely diabetes, atherosclerosis, inflammatory lung disease, cancer, and Alzheimer's disease, and in viral infections.

Cultural conditions affect somatic embryogenesis in Catharanthus roseus L. (G.) Don

  • Aslam, Junaid;Mujib, A.;Fatima, Samar;Sharma, M.P.
    • Plant Biotechnology Reports
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    • v.2 no.3
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    • pp.179-189
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    • 2008
  • We established an efficient plant regeneration system for Catharanthus roseus L. (G.) Don through somatic embryogenesis. Embryogenic callus was induced from hypocotyl of seed germinated in vitro. Somatic embryogenesis in Catharanthus has been categorized into three distinct stages: (1) initiation and proliferation of embryo; (2) maturation, and; (3) germination or plantlet conversion. Beside plant growth regulators, various stages of embryogenesis were screened for their response to a wide variety of factors (pH, gelrite, light, sugar alcohols, polyethyleneglycol and amino acids), which affect embryogenesis. All of the tested factors had a small to marked influence on embryogeny and eventual conversion to plantlets. The plantlets were acclimatized successfully in a greenhouse. To our knowledge, this is the first report describing a detailed study of various cultural factors which regulate embryogenesis in C. roseus. The results discussed in this paper may be used in mass propagation to produce medicinal raw material, and the embryo precursor cells could be used in genetic modification programmes that aim to improve the alkaloid yield as well.

A Sensitivity Analysis of Parameters Affecting Indoor Air Quality Related to TVOC and HCHO Reduction

  • Kang, Hae Jin;Kim, Mi Yeon;Rhee, Eon Ku
    • Architectural research
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    • v.14 no.3
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    • pp.93-98
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    • 2012
  • The objective of the study is to analyze the relative performance of factors affecting indoor air quality in multi-residential buildings in Korea. A study of the factors affecting indoor air quality is essential for establishing indoor air quality management strategies effectively. To observe the indoor air quality response following a modification of a given parameter, a sensitivity analysis was performed. The factors examined for the analysis include; wall/ceiling paper, adhesive for wall/ceiling paper, floor material, adhesive for floor material, and ventilation rate. The Experimental Design which identifies main effects among the design parameters with a few experiments was used to decrease the number of experiments. The simulation for indoor air quality was undertaken using a validated equation. Then, ANOVA(Analysis of Variance) was performed to evaluate the relative importance of each parameter affecting the indoor air quality. The result of the study indicates that the indoor air quality may be influenced most by adhesive for wall/ceiling paper, followed by ventilation rate and adhesive for floor material.

Effect of Demand Spectrums on the Accuracy of Capacity Spectrum Method (요구곡선 산정방법에 따른 능력스펙트럼법의 유효성 평가 및 비교)

  • Kim, Hong-Jin;Min, Kyung-Won;Park, Min-Kyu
    • Journal of the Earthquake Engineering Society of Korea
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    • v.8 no.3
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    • pp.33-42
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    • 2004
  • While transforming the inelastic system into the equivalent elastic one gives an advantage of simpler analysis, the actual inelastic behavior of the system is hardly modeled in the capacity spectrum method (CSM). Therefore, the accuracy of CSM depends on the precise estimation of equivalent period and damping ratio as well as the modification of the elastic response spectrum and the corresponding demand spectrum. In this paper, the effect of demand spectrums on the accuracy of CSM is evaluated. First, the response reduction factors provided in ATC-40 and Euro Code are evaluated. Numerical analysis results indicated that the acceleration responses obtained using the factor of Euro Code are closer to the actual response than those obtained using the factors of ATC-40. Next, the accuracy of CSM is evaluated constructing the demand spectrum using the absolute acceleration responses and pseudo acceleration responses. The results obtained using the absolute acceleration responses were found to be generally larger than those obtained using the pseudo ones. Since CSM often underestimates the response, the use of absolute acceleration response gives the response relatively closer to the exact ones. However, the difference becomes negligible as the hardening ratio and the yield strength ratio become larger.