• Title/Summary/Keyword: H&R

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Biomass Estimation of Shrub Lindera obtusiloba by Allometry

  • Mun, Hyeong-Tae
    • Journal of Ecology and Environment
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    • v.29 no.5
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    • pp.485-488
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    • 2006
  • Allometric equations for biomass measurement of the shrub species, Lindera obtusiloba, were developed. The allometric equations between $(BD)^2H$ and dry weight of leaves ($W_I$), stems and branches ($W_{sb}$), roots ($W_r$) and total weight ($W_t$) of the Lindera obtusiloba were as follows: $W_I=0.7318\;(BD^2H)^{0.6108},\;W_{sb}=0.6067(BD^2H)^{0.8355},\;W_r=0.4524(BD^2H)^{0.7608},\;W_t=1.672 (BD^2H)^{0.7664}$. The $R^2s$ between $(BD)^2H\;and\;W_I,\;W_{sb},\;W_r\;and\;W_t$ of the Lindera obtusiloba were 0.9251, 0.9571, 0.9353 and 0.9546, respectively. Root weight of this Lindera obtusiloba was about 38% of the aboveground biomass.

REAL-VARIABLE CHARACTERIZATIONS OF VARIABLE HARDY SPACES ON LIPSCHITZ DOMAINS OF ℝn

  • Liu, Xiong
    • Bulletin of the Korean Mathematical Society
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    • v.58 no.3
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    • pp.745-765
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    • 2021
  • Let Ω be a proper open subset of ℝn and p(·) : Ω → (0, ∞) be a variable exponent function satisfying the globally log-Hölder continuous condition. In this article, the author introduces the "geometrical" variable Hardy spaces Hp(·)r (Ω) and Hp(·)z (Ω) on Ω, and then obtains the grand maximal function characterizations of Hp(·)r (Ω) and Hp(·)z (Ω) when Ω is a strongly Lipschitz domain of ℝn. Moreover, the author further introduces the "geometrical" variable local Hardy spaces hp(·)r (Ω), and then establishes the atomic characterization of hp(·)r (Ω) when Ω is a bounded Lipschitz domain of ℝn.

Studies on the Histones of the Genus Rhizopus (Rhizopus속의 histones에 관한 연구)

  • 민병례;이은영
    • Korean Journal of Microbiology
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    • v.28 no.2
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    • pp.128-133
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    • 1990
  • The chromatin of all higher eukaryotic cells contains a group of very basic low-mole-cular weight proteins, the histones. But much less is known about histones in lower eukaryotes. Our purpose was to study the histones of the genus Rhizopus. After isolation and purification of nucleoprotein the basic nucleoproteins were analyzed by gel electrophoresis, in sodium dodecyl sulfate as well as acid/urea gels and compared with calf thymus histones. Their electrophoretic mobility in polyacrylamide gel indicate that they are histone homologous, although not identical, to the H2A, H2B, H3 and H4 histones of mammals with the exception of H1. The result suggests that Rhizopus thus appears to contain histone proteins which are homologous to the histones from in higher eukaryotes. The similarity between the calf thymus histone H1 and the Rhizopus high band group remains to be discussed.

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Pharmacokinetics and Tissue Distribution of Recombinant Bovine Somatotropin after Subcutaneous Administarion in Male and Female Rats (Recombinant Bovine Somatotropin의 피하주사 후 Male과 Female Rat에서 약물동태 및 조직분포)

  • Park, Byung-kwon;Park, Seung-chun;Yun, Hyo-in
    • Korean Journal of Veterinary Research
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    • v.43 no.2
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    • pp.203-210
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    • 2003
  • The purpose of this study is to investigate the pharmacokinetics and tissue distribution of recombinant bovine somatotropin (rBST) after subcutaneous adminstration of $^{125}I-rBST$ in male and female rats. A solid state conjugation (Iodo-bead$^{(R)}$) method was confirmed useful for producing $^{125}I-rBST$ because the administration of the conjugated form enabled enough to determine time- concentration relationships of rBST in rats. Subcuatenous administrations showed sex differences that female ($t_{1/2,kc}$, 2.87 h) revealed rapid elimination as compared to male ($t_{1/2,ke}$, 4.81 h), with the absorption ($t_{1/2,ka}$ in male being 0.3 h and that in female 0.75 h) in the reverse order. For subcutaneous administration of rBST in male rats, the liver was the highest in amount, followed by kidney, testes, muscle, and stomach, at the slaughtering tame of 1, 6, 12 and 24 h. But the testes was the highest at the 48 h slaughtered animals, followed by liver, kidney, stomach, and muscle. In slaughtered females at 1, 6, and 12 h after the administration of rBST, the liver was the highest, followed by ovary, kidney, small intestine, and stomach. At 24 and 48 h slaughtered female rats, the ovary was the highest, the liver the second, and the kidney the third.

Polyester (PET) Fabric dyed with Lead (II) acetate-based Colorimetric Sensor for Detecting Hydrogen Sulfide (H2S) (황화수소(H2S) 감지를 위한 아세트산 납이 침염된 폴리에스터(PET) 섬유 기반의 변색성 센서)

  • Lee, Junyeop;Do, Nam Gon;Jeong, Dong Hyuk;Jung, Dong Geon;An, Hee Kyung;Kong, Seong Ho;Jung, Daewoong
    • Journal of Sensor Science and Technology
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    • v.29 no.5
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    • pp.360-364
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    • 2020
  • In this study, the colorimetric sensor, polyester (PET) fabric dyed with lead (II) acetate (Pb(C2H3O2)2), was fabricated and characterized for the detection of the hydrogen sulfide (H2S). The surface morphology of the fabric was determined using scanning electron microscope and energy-dispersive X-ray spectroscopy. The optical properties of the fabric were evaluated by measuring the variation in the blue value of an RGB sensor. The fabric showed a significant color change, high linearity (R2 : 0.98256), and fast response time (< 1.0 s) when exposed to H2S. This is because the sensor is highly porous and permeable to the gas. The fabric can not only be used as a hydrogen sulfide sensor but also be used to detect and prevent H2S influx using sticky tape on pipelines.

Sensitivity enhancement of H2 gas sensor using PbS quantum dots (황화납 양자점 감지막을 통해 감도가 개선된 수소센서)

  • Kim, Sae-Wan;Kim, Na-Ri;Kwon, Jin-Beom;Kim, Jae Keon;Jung, Dong Geon;Kong, Seong Ho;Jung, Daewoong
    • Journal of Sensor Science and Technology
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    • v.29 no.6
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    • pp.388-393
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    • 2020
  • In this study, a PbS quantum dots (QDs)-based H2 gas sensor with a Pd electrode was proposed. QDs have a size of several nanometers, and they can exhibit a high surface area when forming a thin film. In particular, the NH2 present in the ligand of PbS QDs and H2 gas are combined to form NH3+, subsequently the electrical characteristics of the QDs change. In addition to the resistance change owing to the reaction between Pd and H2 gas, the resistance change owing to the reaction between the NH2 of PbS QDs and H2 gas increases the current signal at the sensor output, which can produce a high output signal for the same concentration of H2 gas. Using the XRD and absorbance properties, the synthesis and particle size of the synthesized PbS QDs were analyzed. Using PbS QDs, the sensitivity was significantly improved by 44%. In addition, the proposed H2 gas sensor has high selectivity because it has low reactivity with heterogeneous gases such as C2H2, CO2, and CH4.

Propofol Post-conditioning Protects against COS-7 Cells in Hypoxia/reoxygenation Injury by Induction of Intracellular Autophagy

  • Kwak, Jin-Won;Kim, Eok-Nyun;Park, Bong-Soo;Kim, Yong-Ho;Kim, Yong-Deok;Yoon, Ji-Uk;Kim, Cheul-Hong;Yoon, Ji-Young
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.14 no.1
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    • pp.49-56
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    • 2014
  • Background: Propofol (2.6-diisopropylphenol) is a widely used intravenous anesthetic agent for the induction and maintenance of anesthesia during surgeries and sedation for ICU patients. Propofol has a structural similarity to the endogenous antioxidant vitamin E and exhibits antioxidant activities.13) However, the mechanism of propofol on hypoxia/reoxygenation (H/R) injury has yet to be fully elucidated. We investigated how P-PostC influences the autophagy and cell death, a cellular damage occurring during the H/R injury. Methods: The groups were randomly divided into the following groups: Control: cells were incubated in normoxia (5% CO2, 21% O2, and 74% N2) without propofol treatment. H/R: cells were exposed to 24 h of hypoxia (5% CO2, 1% O2, and 94% N2) followed by 12 h of reoxygenation (5% CO2, 21% O2, and 74% N2). H/R + P-PostC: cells post-treated with propofol were exposed to 24 h of hypoxia followed by 12 h of reoxygenation. 3-MA + P-PostC: cells pretreated with 3-MA and post-treated propofol were exposed to 24 h of hypoxia followed by 12 h of reoxygenation Results: The results of our present study provides a new direction of research on mechanisms of propofol-mediated cytoprotection. There are three principal findings of these studies. First, the application of P-PostC at the onset of reoxygenation after hypoxia significantly increased COS-7 cell viability. Second, the cellular protective effect of P-PostC in H/R induced COS-7 cells was probably related to activation of intra-cellular autophagy. And third, the autophagy pathway inhibitor 3-MA blocked the protective effect of P-PostC on cell viability, suggesting a key role of autophagy in cellular protective effect of P-PostC. Conclusions: These data provided evidence that P-PostC reduced cell death in H/R model of COS-7 cells, which was in agreement with the protection by P-PostC demonstrated in isolated COS-7 cells exposed to H/R injury. Although the this study could not represent the protection by P-PostC in vivo, the data demonstrate another model in which endogenous mechanisms evoked by P-PostC protected the COS-7 cells exposed to H/R injury from cell death.

The Shape of Polymers Resulted Condensation in the Mixed Si(OC_2H_5)_4 and Zr(O-nC_3H_7)_4$4 Solutions (Si(OC_2H_5)_4와 Zr(O-nC_3H_7)_4$ 혼합용액의 중합반응에 따른 고분자의 형상)

  • 신대용;한상목
    • Journal of the Korean Ceramic Society
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    • v.31 no.2
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    • pp.220-226
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    • 1994
  • The hydrolysis and condensation reactions in the mixed alkoxide solutions of Si(OC2H5)4 and Zr(O-nC3H7)4 with various water contents (1, 2, 4, and 8 in molar ratio to alkoxide, r) and catalysts were examined by rheological measurements and the number average molecular weight in order to explain the shape of the polymer in the mixed alkoxide solutions. It was found that fibers could be drawn in the viscosity range of 1∼100P from the acid-catalyzed solutions with lower water contents of the mole ratio H2O/alkoxide, r 2. On the other hand, crack free bulk gel was formed from the acid-catalyzed solutions including a large amount of water (r 4), and the base-catalyzed solutions. The relation between the intrinsic viscosity [{{{{ eta }}] and the number average molecular weight n, namely [{{{{ eta }}]=Knα, has shown that the acid-catalyzed spinnable solutions (r=1 and 2) have linear polymers and the exponent α's are about 0.56 and 0.81, whereas non-spinnable solutions (r=4 and 8) have three dimensional network polymers or spherical particles and the exponent α's are 0.41∼0.51 and 0.35.

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Medium Voltage Inverter System Using Decentralized Control (분산제어를 이용한 고압인버터 시스템)

  • Jang, H.K.;Kim, H.J.;Jeon, J.H.;Yun, H.M.;Na, S.H.
    • Proceedings of the KIPE Conference
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    • 2007.07a
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    • pp.464-466
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    • 2007
  • H-Bridge Multi-Level (HBML) 고압인버터는 저압의 반도체 소자를 사용하는 단상 H-Bridge 인버터로 구성 된 셀을 직렬로 연결함으로써 정현파에 가까운 고전압을 얻을 수 있고, 입 출력 고조파가 낮아서 필터가 필요 없는 토폴로지로 산업분야에서 사용이 확대되고 있다. 본 논문은 HBML 고압인버터의 마스터 제어기와 셀 제어기의 통신 하드웨어를 병렬로 구성하여서 하나의 전압지령 값과 Angle 값으로 셀에서 PWM을 구현 할 수 있는 분산제어 방식을 제안한다. 이 방식에서 셀 제어기가 전압, 전류, 주파수, 보호기능, 통신감시 정보 등 셀 제어의 대부분을 담당함으로써 마스터 제어기의 부담을 줄이고, 따라서 신호선의 개수를 줄일 수 있다. 또 통신하드웨어의 종단에 마스터 제어기를 연결만 하면 마스터제어기의 2중화가 가능하므로 사용하고 있던 마스터 제어기의 고장 발생 시에 대체하여 사용할 수 있으므로 시스템의 안정성 향상에 도움을 준다. 선간전압 33레벨로 구성된 HBML 고압인버터 시험을 통해 제안된 방식의 타당성과 신뢰성을 검증한다.

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ON THE LOCAL COHOMOLOGY OF MINIMAX MODULES

  • Mafi, Amir
    • Bulletin of the Korean Mathematical Society
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    • v.48 no.6
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    • pp.1125-1128
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    • 2011
  • Let R be a commutative Noetherian ring, a an ideal of R, and M a minimax R-module. We prove that the local cohomology modules $H^j_a(M)$ are a-cominimax; that is, $Ext^i_R$(R/a, $H^j_a(M)$) is minimax for all i and j in the following cases: (a) dim R/a = 1; (b) cd(a) = 1, where cd is the cohomological dimension of a in R; (c) dim $R{\leq}2$. In these cases we also prove that the Bass numbers and the Betti numbers of $H^j_a(M)$ are finite.