• Title/Summary/Keyword: Expansion mechanism

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Regulation Mechanism of Soybean Storage Protein Gene Expression (대두 저장단백질 유전자의 발현 조절 메카니즘)

  • 최양도;김정호
    • Proceedings of the Botanical Society of Korea Conference
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    • 1987.07a
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    • pp.283-307
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    • 1987
  • Glycinin and $\beta$-conglycinin are the most abundant storage protein in soybean. These proteins are known to be synthesized predominantly during germination and cell expansion phase of seed development for short period, and synthesized not in other tissues. Genes encoding these storage proteins are useful system to study the mechanism of development stage and tissue specific gene expression in eukaryotes, especially plants, at the molecular level. The cDNA and genomic clones coding for glycinin have been isolated and regulation mechanism of the gene expression has been studied. Initially, development and tissue-specific expression of the glycinin gene is regulated at the level of transcription. Post-transcriptional processing is also responsible for delayed accumulation of the mRNA. Translational control of the storage protein gene has not been reported. Post-translational modification is another strategic point to regulate the expression of the gene. It is possible to identify positive and/or negative reguratory clements in vivo by producing transgenic plants agter gene manipulation. Elucidation of activation and repression mechanism of soybean storage protein genes will contribute to the understanding of the other plant and eukaryotic genes at molecular level.

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A Research about optimum design of the walking robot using Jansen mechanism (얀센 메커니즘을 이용한 보행로봇의 최적설계에 관한 연구)

  • YONGZHU, JIN;Chi, Hyoung Geun
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.384-388
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    • 2016
  • This paper proposed a m.Sketch to search the optimal link lengths for a legged walking robot. In order to apply the m.Sketch for the proposed, set the design parameters of the constraints and use the m.Skecth to get optimal GL(Groud Length) and GAC(Ground Angle Coefficient). The legged robot designed based on four-bar linkage theory and Theo Jansen mechanism. The stride length of the legged walking robot was defined based on the proposed kinematic analysis. Use the Edison Design m.Sketch simulate and find the optimal link length having the best of the Ground Length (GL) and Ground Angle Coefficient(GAC). And use these length implemented the Theo Jansen mechanism both in Science box parts and acrylic. In addition to the further expansion of the legs to reach the goaltranslating heavy objects or person.

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A Study on the Distribute Authentication Method Scheme through Authentication and Right Mechanism Trend of the Ubiquitous Environment (유비쿼터스 환경의 인증 및 권한 메커니즘 동향을 통한 분산 인증기법 방안 연구)

  • Oh, Dong-Yeol;Sung, Kyung-Sang;Kim, Bae-Hyun;Oh, Hae-Seok
    • Convergence Security Journal
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    • v.8 no.1
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    • pp.35-42
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    • 2008
  • While an information system and administration for an application that a user contacts with raise a head by an important problem, a system approach and methodology for administration are mentioned. Authentication technology of various configuration is used, but non-efficiency by complicated authentication administration and operation inappropriate use are for a successful expansion of various and new business of wire/wireless environment. In addition, under the mobile computer environment with different authentic method each other, it is difficult at all to expect flexible and continuous service. Under the ubiquitous computing environment, It is very important thing plan to research and develop compatibility and the side of variance authentication plan that preservation characteristics are helped. Hereby, This paper look around an requirement items and authority mechanism for the administration and the operation mechanism of the distributed authentication considering expansion possibility of the ubiquitous computing environment not only fixed computing environment but also mobile computing. In future, we expect it by can guide positive participation about distributed authentication technique of the genuine ubiquitous environment.

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Effects of Trichostatin A on Cumulus Expansion during Mouse Oocyte Maturation

  • Du, Ming;Fu, Xiangwei;Zhou, Yanhua;Zhu, Shien
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.11
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    • pp.1545-1552
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    • 2013
  • This study was conducted to investigate the effects of Trichostatin A (TSA) on cumulus expansion during mouse oocyte maturation. TSA treatment inhibited cumulus expansion and significantly reduced the cumulus expansion index (CEI) (p<0.05). To determine the underlying mechanism, the expression levels of several key factors that play crucial roles in cumulus expansion including components of extracellular matrix (ECM) (Has2, Ptgs2, Ptx3, and Tnfaip6) and Growth differentiation factor 9 (GDF9) were measured in control and TSA treated samples by real-time PCR. The effect of TSA on ERK phosphorylation (p-ERK1/2) in cumulus cells and GDF9 protein level in fully grown oocytes (FGOs) were detected by Western blotting. The expression levels of the ECM genes were significantly decreased (p<0.05) by TSA treatment while GDF9 expression did not response to TSA (p>0.05). TSA treatment blocked the activation of ERK1/2 (p<0.05) and had no significant effect on GDF9 protein expression (p>0.05). Collectively, these results suggested that TSA treatment altered ECM gene expression and blocked ERK1/2 activation to inhibit cumulus expansion in the mouse.

Disparities in High-cost Outpatient Imaging Test Utilization between Private Health Insurance Subscribers and Non-subscribers: Changes Following the National Health Insurance Benefit Expansion Policy (민간의료보험 가입자와 미가입자 간 외래 고가영상검사 이용의 격차: 건강보험 보장성 강화 정책에 따른 변화)

  • Yukyung Shin;Young Kyung Do
    • Health Policy and Management
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    • v.33 no.3
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    • pp.325-337
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    • 2023
  • Background: While there are many studies estimating the effects of private health insurance on various types of health care utilization, few have examined how such effects change in conjunction with important policy reforms in national health insurance (NHI). This study examined how the effect of private health insurance (supplemental and fixed cash benefit) on high-cost outpatient imaging test utilization changed following the expansion of magnetic resonance imaging (MRI) coverage in 2018, which is a key example of the NHI benefit expansion policy in recent years. Methods: Data from the 2017 and 2019 Korea Health Panel Survey, which contained information about healthcare utilization before and after the expansion of MRI coverage in 2018, were used. The incremental effect of private health insurance on high-cost outpatient imaging test utilization for each period were quantified and compared, with special attention given to the type of private health insurance. Results: While people with supplemental private health insurance were more likely to use high-cost outpatient imaging tests than those without, both before and after the expansion of MRI coverage, the incremental effect increased from 1.6% points in 2017 to 2.5% points in 2019. Conclusion: Benefit expansion in NHI does not necessarily reduce disparities in the use of health care between private health insurance subscribers and non-subscribers. The results of our study also suggest that the path through which private health insurance affects healthcare utilization may not be limited to the price mechanism alone but can be more complex.

An Investigation on the Existing Literature to Prevent Fire Spread of High-rise Buildings (고층 건축물의 화재확대방지를 위한 기존 문헌 조사)

  • Lee, Byeong-Heun;Kwon, Young-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2021.05a
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    • pp.102-103
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    • 2021
  • In Korea, starting with the Busan residential-commercial fire in 2010, the frequency of fire expansion in high-rise buildings has been continuously increasing. In the case of such large-scale fires, most of the fires generated from the inside tend to expand to the upper floors by riding the exterior material or exterior wall panels through the process of being ejected to the outside. It has been revised so that combustible exterior materials cannot be used in buildings. However, due to the legal fluoride level, the fire risk of high-rise buildings is still high, such as the case of a 33-story residential-commercial fire in Ulsan. In order to prevent such fire expansion, it is considered that it is necessary to first understand the nature of the fire occurring inside and the mechanism of the fire expansion in the upper floor. The purpose of this study is to propose improvements in domestic fire safety design through a review of existing literature to prevent fire expansion of high-rise buildings.

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Transcriptional Regulation of Lipogenesis and Adipose Expansion (Lipogenesis와 adipose expansion의 전사조절)

  • Jang, Younghoon
    • Journal of Life Science
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    • v.32 no.4
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    • pp.318-324
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    • 2022
  • PPARγ and C/EBPα are master adipogenic transcription factors (TFs) required for adipose tissue development. They control the induction of many adipocyte genes and the early phase of adipogenesis in the embryonic development of adipose tissue. Adipose tissue continues to expand after birth, which, as a late phase of adipogenesis, requires the lipogenesis of adipocytes. In particular, the liver and adipose tissues are major sites for de novo lipogenesis (DNL), where carbohydrates are primarily converted to fatty acids. Furthermore, fatty acids are esterified with glycerol-3-phosphate to produce triglyceride, a major source of lipid droplets in adipocytes. Hepatic DNL has been actively studied, but the DNL of adipocytes in vivo remains not fully understood. Thus, an understanding of lipogenesis and adipose expansion may provide therapeutic opportunities for obesity, type 2 diabetes, and metabolic diseases. In adipocytes, DNL gene expression is transcriptionally regulated by lipogenesis coactivators, as well as by lipogenic TFs such as ChREBP and SREBP1a. Recent in vivo studies have revealed new insights into the lipogenesis gene expression and adipose expansion. Future detailed molecular mechanism studies will determine how nutrients and metabolism regulate DNL and adipose expansion. This review will summarize recent updates of DNL in adipocytes and adipose expansion in terms of transcriptional regulation.

Characterization of the brittleness of hard rock at different temperatures using uniaxial compression tests

  • Chen, Guoqing;Li, Tianbin;Wang, Wei;Guo, Fan;Yin, Hongyu
    • Geomechanics and Engineering
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    • v.13 no.1
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    • pp.63-77
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    • 2017
  • The failure mechanism of a deep hard rock tunnel under high geostress and high geothermalactivity is extremely complex. Uniaxial compression tests of granite at different temperatures were conducted. The complete stress-strain curves, mechanical parameters and macroscopic failure types of the rock were analyzed in detail. The brittleness index, which represents the possibility of a severe brittleness hazard, is proposed in this paperby comparing the peak stress and the expansion stress. The results show that the temperature range from 20 to $60^{\circ}C$ is able to aggravate the brittle failure of hard rock based on the brittleness index. The closure of internal micro cracks by thermal stress can improve the strength of hard rock and the storage capacity of elastic strain energy. The failure mode ofthe samples changes from shear failure to tensile failure as the temperature increases. In conclusion, the brittle failure mechanism of hard rock under the action of thermal coupling is revealed, and the analysis result offers significant guidance for deep buried tunnels at high temperatures and under high geostress.

Atomistic Investigation of Lithiation Behaviors in Silicon Nanowires: Reactive Molecular Dynamics Simulation

  • Jeong, Hyeon;Ju, Jae-Yong;Jo, Jun-Hyeong;Lee, Gwang-Ryeol;Han, Sang-Su
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.160.2-160.2
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    • 2014
  • Recently silicon has attracted intense interest as a promising anode material of lithium-ion batteries due to its extremely high capacity of 4200 mA/g (for Li4.2Si) that is much higher than 372 mAh/g (for LiC6) of graphite. However, it seriously suffers from large volume change (even up to 300%) of the electrode upon lithiation, leading to its pulverization or mechanical failure during lithiation/delithiation processes and the rapid capacity fading. To overcome this problem, Si nanowires have been considered. Use of such Si nanowires provides their facile relaxation during lithiation/delithiation without mechanical breaking. To design better Si electrodes, a study to unveil atomic-scale mechanisms involving the volume expansion and the phase transformation upon lithiation is critical. In order to investigate the lithiation mechanism in Si nanowires, we have developed a reactive force field (ReaxFF) for Si-Li systems based on density functional theory calculations. The ReaxFF method provides a highly transferable simulation method for atomistic scale simulation on chemical reactions at the nanosecond and nanometer scale. Molecular dynamics (MD) simulations with the ReaxFF reproduces well experimental anisotropic volume expansion of Si nanowires during lithiation and diffusion behaviors of lithium atoms, indicating that it would be definitely helpful to investigate lithiation mechanism of Si electrodes and then design new Si electrodes.

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