• Title/Summary/Keyword: H1-H2

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Preparation and Stability of Silyl Adlayers on 2×1-Reconstructed and Modified Si(100) Surfaces (Si(100)-2×1 표면과 개질된 Si(100) 표면 상에서 실릴 (Silyl) 흡착충의 형성과 안정성)

  • Jo, Sam-K.
    • Journal of the Korean Vacuum Society
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    • v.18 no.1
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    • pp.15-23
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    • 2009
  • Saturation-coverage silyl, $-SiH_3(a)$, overlayers were prepared from $Si_2H_6$ adsorption on three comparative surfaces: clean unmodified; D-precovered; and atomically roughened Si(100). Together with its precursor-mediated adsorption behavior, the surface reactivity of $Si_2H_6$ was found to be the highest on the unmodified Si(100)-$2{\times}1$ surface. This was correlated with its dissociative adsorption mechanism, in which both the $H_3Si-SiH_3$ bond scission and the dual surface $Si-SiH_3(a)$ bond formation require a surface dangling bond 'pair'. The unusually high thermal stability of $-SiH_3(a)$ on the unmodified surface was ascribed to a nearly close-packed $-SiH_3(a)$ coverage of ${\sim}0.9$ monolayer and the consequent lack of dangling bonds on the silyl-packed surface.

Aberrant DNA Methylation of P16, MGMT, hMLH1 and hMSH2 Genes in Combination with the MTHFR C677T Genetic Polymorphism in Gastric Cancer

  • Xiong, Hai-Lin;Liu, Xun-Qi;Sun, Ai-Hua;He, Ying;Li, Jun;Xia, Yuan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.3139-3142
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    • 2013
  • Associations of P16, MGMT, hMLH1 and hMLH2 with gastric cancer and their relation with MTHFR status in gastric patients who were confirmed with pathological diagnosis were assessed. Aberrant DNA methylation of P16, MGMT, hMLH1 and hMLH2 and polymorphisms of MTHFR C677T were assayed. The proportional DNA hypermethylation in P16, MGMT, hMLH1 and hMLH2 in cancer tissues was significantly higher than in remote normal-appearing tissues. DNA hypermethylation of P16 and MGMT was correlated with the T and N stages. Individuals with homozygotes (TT) of MTHFR C677T had significant risk of hypermethylation of MGMT in cancer tissues [OR (95% CI)= 3.47(1.41-7.93)]. However, we did not find association between polymorphism in MTHFR C677T and risk of hypermethylation in P16, MGMT, hMLH1 and hMLH2 genes either in cancer or remote normal-appearing tissues. Aberrant hypermethylation of P16, MGMT, hMLH1 and hMLH2 could be predictive of gastric cancer.

Increased Expression of the ${\alpha}_2$ Isoform of (Na,K)ATPase in the Differentiated Murine Muscle Cell Line BC3H-1 (BC3H-1 분화세포에서의 (Na,K)ATPase ${\alpha}_2$ isoform의 표현증대)

  • Lee, Kyung-Lim
    • YAKHAK HOEJI
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    • v.40 no.6
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    • pp.734-738
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    • 1996
  • The development of the alpha2 isoform of (Na,K)ATPase which is high affinity ouabain receptors was studied in the differentiating nonfusing muscle cell line BC3H-1. T he differentiation process of BC3H-1 cell line was confirmed by 2-dexy-D-[$^3$H] glucose uptake experiment and the quantity of the expression of ${\alpha}_2$ isoform was measured using a whole cell [$^3$H] ouabain-binding assay. Undifferentiated growing BC3H-1 cells, myoblasts, exhibited low levels of insulin-stimulated glucose uptake and [$^3$H] ouabain-binding sites. In contrast, differentiated BC3H-1 cells, myocytes, had a 5.6-fold increase in insulin-stimulated glucose uptake and 5-fold increase in [$^3$H] ouabain-binding sites. Scatchard analysis showed that myocytes developed more [$^3$H] ouabain-binding sites than myoblasts vath a dissociation constant (kd) of 6${\times}10^{-8}$M and capacity of 6.l${\times}10^{-5}$ sites/cell. Therefore. it seems that myoblasts express low levels of ${\alpha}_2$ subunit and probably the majority of ${\alpha}_1$ subunit, whereas myocytes express high levels of ${\alpha}_2$ isoform. The results indicate that the expression of ${\alpha}_2$ isoform is developmentally regulated during differentiation and that BC3H-1 culture system provides an excellent model for the study of differentiation and mechanism of (Na,K)ATPase action in muscle which requires electrical excitability.

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The Effect of Leadership Types of Managers Perceived by ICT Organization Members on Leadership Trust and Job Satisfaction

  • Kim, Moon Jun
    • International journal of advanced smart convergence
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    • v.9 no.2
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    • pp.212-223
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    • 2020
  • We study to confirm the relationship between leadership trust and job satisfaction on the leadership style of managers recognized by ICT organization members. To this end, the research hypothesis established by using SPSS23.0 for the survey results of 230 ICT organization members was analyzed as follows. First, the hypothesis 1 person leadership type (individual consideration: H1-1, intellectual stimulation: H1-2, charisma: H1-3, conditional compensation: H1-4, exceptional reward: H1-5) had a significant effect on leader trust. The results were obtained. Second, the hypothesis 2 manager's leadership type (individual consideration: H21-1, intellectual stimulation: H2-2, charisma: H2-3, conditional compensation: 2-4, expected compensation: H2-5) is based on job satisfaction. As a result of verifying the impact relationship, all showed significant effect on job satisfaction. Third, it acted as a positive factor in the job satisfaction of the leader of the hypothesis 3-member organizational member. It was confirmed that the job satisfaction of organizational members started based on the trust of actual leaders. Fourth, the role of leadership trust was partially confirmed between leadership type and job satisfaction. Through this study, in order to improve job satisfaction of ICT organizational members, the importance of exerting competency on the leadership type of managers and trusting the leaders on the characteristics consistent with ICT organizational characteristics was emphasized.

The Enhancement of Cytochrome P-450 Mediated Aryl Hydroxylation of Bentazon in Rice Microsomes (벼에서 Bentazon 히드록시화반응에 관련된 Cytochrome P-450 활성(活性) 증진(增進)에 관한 연구(硏究))

  • Pyon, J.Y.;Balke, N.E.
    • Korean Journal of Weed Science
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    • v.17 no.1
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    • pp.59-65
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    • 1997
  • Bentazon 6-hydroxylase (B6H) and cinnamic acid 4-hydroxylase (CA4H) activities were determined in rice (Oryza sativa L.) microsomes to study methods of enhancing cytochrome P-450 mediated aryl hydroxylation of bentazon by hydoxylase inducing compounds. Pretreating rice seeds with 1,8-naphthalic anhydride at 0.5-2% and fenclorim at 5 and 10 ${\mu}M$ increased B6H and CA4H activities. Treatments of rice seedling with ethanol 2.5% enhanced B6H and CA4H activities, and with phenobarbital at 12 mM enhanced B6H activity, and CA4H activity was enhanced at 2 mM. B6H activity was synergistically enhanced by combined treatments of ethanol 2.5 or 5% and phenobarbital 8 or 12mM and also that of 1,8-naphthalic anhydride 0.5 or 1% and phenobarbital 8 or 12 mM, but CA4H activity was decreased by combined treatment. Five-day-old rice seedlings showed higher B6H and CA4H activities which decreased with seedling age.

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First-Principles Investigation on the Electromechanical Properties of Monolayer 1H Pb-Dichalcogenides

  • Nguyen Hoang Linh;Nguyen Minh Son;Tran The Quang;Nguyen Van Hoi;Vuong Thanh;Do Van Truong
    • Korean Journal of Materials Research
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    • v.33 no.5
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    • pp.189-194
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    • 2023
  • This study uses first-principles calculations to investigate the mechanical properties and effect of strain on the electronic properties of the 2D material 1H-PbX2 (X: S, Se). Firstly, the stability of the 1H Pb-dichalcogenide structures was evaluated using Born's criteria. The obtained results show that the 1H-PbS2 material possesses the greatest ideal strength of 3.48 N/m, with 3.68 N/m for 1H-PbSe2 in biaxial strain. In addition, 1H-PbS2 and 1H-PbSe2 are direct semiconductors at equilibrium with band gaps of 2.30 eV and 1.90 eV, respectively. The band gap was investigated and remained almost unchanged under the strain εxx but altered significantly at strains εyy and εbia. At the fracture strain in the biaxial direction (19 %), the band gap of 1H-PbS2 decreases about 60 %, and that of 1H-PbSe2 decreases about 50 %. 1H-PbS2 and 1H-PbSe2 can convert from direct to indirect semiconductor under the strain εyy. Our findings reveal that the two structures have significant potential for application in nanoelectronic devices.

The Developmental Characterization of the Sericin jam(Bombyx mori), a Mutant in the Synthesis and Secretion of Fibroin (세리신잠(Nd-s. $Nd^H$의 발육 특성)

  • 김수연;손해룡
    • Journal of Sericultural and Entomological Science
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    • v.45 no.1
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    • pp.6-9
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    • 2003
  • This experiment was done to know developmental characteristics of Sericin jam. Incubation periods were 10 day 2 hr, and 10 day 1 hr. 11 day 1 hr for Nd-s jam, N $d^{H}$ jam, and Baegok jam, respectively. Hatching rates were 83.9, 83.3 and 96.0% for Nd-s jam, N $d^{H}$ jam, and Baegok jam. Larval periods were, 20 days 1 hr for Nd-s jam, 20 days 5 hrs for N $d^{H}$ jam, and 22 days 12 hrs for Baegok jam. Death rate of larvae was highest in N $d^{H}$ iam, followed by Nd-s jam and Baegok jam. Pupation rate was highest in Baegok Jam followed by Nd-s jam and that of N $d^{H}$ jam was the lowest among the three. Cocoon weight was 1.39, 1.08, and 2.01 g for Nd-s jam, N $d^{H}$ jam, and Baegok jam, respectively. Shell weight were 13, 3, and 48 cg for Nd-s jam, N $d^{H}$ jam, and Baegok jam. Cocoon shell ratios were 9.0% for Nd-s jam, 2.8% for N $d^{H}$ jam and 23.9% for Baegok jam. Cocoon sizes were 30.6${\times}$15.8 mm for Nd-s jam, 24.7${\times}$14.9 mm for N $d^{H}$ jam and 35.8 ${\times}$ 20.5 mm(1${\times}$w) for Baegok jam.w) for Baegok jam.

pH Effect at Thermophilic Solubilization Pretreatment of Food Waste in Two Phase Anaerobic Digestion (2상 혐기성 소화에서 음식물쓰레기의 고온 가용화 전처리 pH 영향)

  • Lee, Won-Soo;Kang, Young-Jun;Seo, Gyu-Tae
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.8
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    • pp.452-458
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    • 2016
  • The study on pH control at the themophilic solubilization (pretreatment process) was investigated in order to improve the methane gas production of two phase anaerobic digestion of food waste. From a batch experiment, it was observed that the solubilization efficiency was increased from 26.2% to 47.1% and 55.6% by the pH increament from $4.20{\pm}0.40$ (without pH control) to $7.00{\pm}0.50$, and $12.00{\pm}0.50$, respectively. However there was immaterial increase (8.5%) in solubilization efficiency when the pH was increased from $7.00{\pm}0.50$ to $12.00{\pm}0.50$. The two phase anaerobic digestion system was operated for laboratory scale experiment under the solubilization condition of pH $4.20{\pm}0.40$ (Run1) and $7.00{\pm}0.50$ (Run2). Higher soluble chemical oxygen demand (SCOD) and total volatile fatty acid (TVFA) concentration were observed in Run2 throughout the system resulted by the solubilization effect at the pH $7.00{\pm}0.50$. The TVFA concentration in acidogenic reactor was 18.4 g/L which was 1.8 times higher than the result of Run1. Consequently the methane gas production was enhanced to 0.333 L/g VS in the methanogenic reactor, which is 18% higher than the result (0.282 L/g VS) of Run1.

Excess proton catalyzed H/D exchange reaction at the ice surface

  • Moon, Eui-Seong;Kang, Heon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.333-333
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    • 2011
  • We studied the H/D exchange kinetics of pure and acid dopped water-ice film by using the techniques of reactive ions scattering (RIS) and low energy sputtering (LES) with low kinetic energy cesium ion beam (<35 eV). From RIS, neutral water isotopomers were detected in the form of cesium-molecule ion clusters, $CsX^+$ (X= $H_2O$, HDO, $D_2O$). Ionic species, like $H_3O^+$, $DH_2O^+$, $D_2HO^+$, $D_3O^+$, adsorbed on the surface were ejected via LES process. Those techniques allowed us to trace the isotopomeric populations of water-ice film. To show the catalytic effect of excess proton in the H/D exchange reaction, our study was conducted with two types of water-ice films. In film 1, about 0.5 BL of $H_2O$ was adsorbed on HCl (0.1 ML) dopped $D_2O$ (8 BL) film. In film 2, similar amount of $H_2O$ used in film 1 was adsorbed on pure $D_2O$ film. Kinetic data were obtained from each film type for 90-110 K (film 1) and 110-130 K (film 2) and fitted with numerically integrated lines. Through the Arrhenius plot of kinetic coefficient deduced from fitting of the H/D exchange reaction, the activation energy of film 1 and 2 were estimated to be $10{\pm}3kJmol^{-1}$ and $17{\pm}4kJmol^{-1}$. This activation barrier difference could be understood from detailed pictures of H/D exchange. In film 2, both the formation of ion pair, $H_3O^+$ and OH. and proton transfer were needed for the H/D exchange. However, in film 1, only proton transfer was necessary but ion pair formation was not, so this might reduce the activation energy.

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On Lagrangian Approach to Mixed $H_2$/H\ulcorner Control Problem: The State Feedback Case

  • Cho, Kwang-Hyun;Lim, Jong-Tae
    • Journal of Electrical Engineering and information Science
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    • v.1 no.1
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    • pp.29-38
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    • 1996
  • To improve the reliability of control systems, certain robustness to plant uncertainties and disturbance inputs is required in terms of well founded mathematical basis. Robust control theory was set up and developed until now from this motivation. In this field, H$_2$or H\ulcorner norm performance measures are frequently used nowadays. Moreover a mixed H$_2$/H\ulcorner control problem is introduced to combine the merits of each measure since H$_2$control usually makes more sense for performance while H\ulcorner control is better for robustness to plant perturbations. However only some partial analytic solutions are developed to this problem under certain special cases at this time. In this paper, the mixed H$_2$/H\ulcorner control problem is considered. The analytic(or semi-analytic) solutions of (sub)optimal mixed H$_2$/H\ulcorner state-feedback controller are derived for the scalar plant case and the multivariable plant case, respectively. An illustrative example is given to compare the proposed analytic solution with the existing numerical one.

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