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A Formulation Study for the Controled Release Rate of Diltiazem. HCl using the Multiple Drug Release System (다중약물방출시스템을 이용한 염산딜티아젬의 방출속도 조절에 관한 연구)

  • Kim, Hak-Hyung;Oh, Jin-Hwan;Han, Kun
    • Journal of Pharmaceutical Investigation
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    • v.35 no.3
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    • pp.157-163
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    • 2005
  • The pellets with multiple drug release system (MDRS) of Diltiazem. HCl which consist of immediate drug release layer, drug reservoir layer and controlled release rate membrane, were prepared by using CF-Coater. As main factors for more effective MDRS of Diltiazem. HCl, ethylcellulose was used for the controlling drug release rate, and diethylphthalate was used for plasticizer, respectively. In vitro evaluation study was performed by comparative dissolution test between our test MDRS and reference Diltiazem. HCl preparation. The physical tests were performed using FT-IR and SEM. In vivo evaluation was also performed by observing the behavior of a plasma drug concentration after oral administration. The bioavailability was determined by analyzing the blood sample after oral administration to healthy, male volunteers once a day. As a result, there were no significant differences in bioequivalence parameters $(AUC_{\infty},\;C_{max},\;t_{1/2})$ between two systems. It might be concluded that our MDRS of Diltiazem. HCl could be an alternative delivery system to reference drug preparation.

AT LEAST TWO SOLUTIONS FOR THE ASYMMETRIC BEAM SYSTEM WITH CRITICAL GROWTH

  • Jung, Tacksun;Choi, Q-Heung
    • Korean Journal of Mathematics
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    • v.19 no.3
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    • pp.331-342
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    • 2011
  • We consider the multiplicity of the solutions for a class of a system of critical growth beam equations with periodic condition on t and Dirichlet boundary condition $$\{u_{tt}+u_{xxxx}=av+\frac{2{\alpha}}{{\alpha}+{\beta}}u_{+}^{{\alpha}-1}v_{+}^{\beta}+s{\phi}_{00}\;\;in\;(-\frac{\pi}{2},\;\frac{\pi}{2}){\times}R,\\u_{tt}+v_{xxxx}=bu+\frac{2{\alpha}}{{\alpha}+{\beta}}u_{+}^{\alpha}v_{+}^{{\beta}-1}+t{\phi}_{00}\;\;in\;(-\frac{\pi}{2},\;\frac{\pi}{2}){\times}R,$$ where ${\alpha}$, ${\beta}$ > 1 are real constants, $u_+=max\{u,0\}$, ${\phi}_{00}$ is the eigenfunction corresponding to the positive eigenvalue ${\lambda}_00=1$ of the eigenvalue problem $u_{tt}+u_{xxxx}={\lambda}_{mn}u$. We show that the system has a positive solution under suitable conditions on the matrix $A=\(\array{0&a\\b&0}\)$, s > 0, t > 0, and next show that the system has another solution for the same conditions on A by the linking arguments.

Effect of Cyclohexane Treatment on the Liver Cytochrome P-450 Dependent Aniline Hydroxylase Activity in Alcohol-pretreated Rats (알코올 전처치한 흰쥐에 Cyclohexane 투여가 Cytochrome P-450 dependent aniline hydroxylase 활성에 미치는 영향)

  • 김병렬;윤종국
    • Journal of Environmental Health Sciences
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    • v.29 no.2
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    • pp.23-28
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    • 2003
  • To evaluate the effect of cyclohexane(CH) treatment on the liver cytochrome P-450 dependent aniline hydroxylase(CYPdAH) activity in alcohol-pretreated animals, CH(1.56 g/kg body weight) was intraperitoneally administered to Sprague-Dawley male rats, which had been drunk 15% alcohol in distilled water for 1,3 and 6 weeks. CH was injected to rats 4 times every other day and the animals were sacrificed at 24 hours after injection of CH. In the alcohol-pretreated rats, liver injuries were not demonstrated on the basis of the liver weight per body weight, the levels of serum alanine aminotransferase and hepatic microsomal glucose-6-phosphatase activities. By the CH treatment, alcohol-pretreated animals showed the significantly increased activity of hepatic microsomal CYPdAH. Concomitantly $V_{max}$ value in CYPdAH was more increased, whereas $K_{M}$ value more decreased in alcohol-pretreated animals by the treatment of CH. In conclusion, the increasing cause of microsomal CYPdAH in CH-treated rats pretreated with alcohol may be due to induction of enzyme protein in rat liver.r.r.

Cementing failure of the casing-cement-rock interfaces during hydraulic fracturing

  • Zhu, Hai Y.;Deng, Jin G.;Zhao, Jun;Zhao, Hu;Liu, Hai L.;Wang, Teng
    • Computers and Concrete
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    • v.14 no.1
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    • pp.91-107
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    • 2014
  • Using the principle of damage mechanics, zero-thickness pore pressure cohesive elements (PPCE) are used to simulate the casing-cement interface (CCI) and cement-rock interface (CRI). The traction-separation law describes the emergence and propagation of the PPCE. Mohr-coulomb criteria determines the elastic and plastic condition of cement sheath and rock. The finite element model (FEM) of delamination fractures emergence and propagation along the casing-cement-rock (CCR) interfaces during hydraulic fracturing is established, and the emergence and propagation of fractures along the wellbore axial and circumferential direction are simulated. Regadless of the perforation angle (the angle between the perforation and the max. horizontal principle stress), mirco-annulus will be produced alonge the wellbore circumferential direction when the cementation strength of the CCI and the CRI is less than the rock tensile strength; the delamination fractures are hard to propagate along the horizontal wellbore axial direction; emergence and propagation of delamination fractures are most likely produced on the shallow formation when the in-situ stresses are lower; the failure mode of cement sheath in the deep well is mainly interfaces seperation and body damange caused by cement expansion and contraction, or pressure testing and well shut-in operations.

Target Strength According to Tilt Angle and Length of Black Seabream Acanthopagrus schlegeli at 200 kHz-frequency (감성돔(Acanthopagrus schlegeli)의 유영자세각과 체장에 따른 200 kHz대역 음향산란강도)

  • Choi, Jung-Hwa;Oh, Woo-Seok;Yoon, Euna;Im, Yang-Jae;Lee, Kyounghoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.51 no.5
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    • pp.566-570
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    • 2018
  • This study determined the acoustic target strength (TS; dB) of black seabream Acanthopagrus schlegeli off the southern coast of Korea. For the ex-situ measurements, 200 kHz split beam transducers were used, and a Kirchhoff-ray mode (KRM) model acoustic model was used for the calculation. The fork length and total weight of the black seabream ranged from 6.4 to 30.8 cm and 6.4 to 683.8 g. respectively 200 kHz, the TS could beexpressed as a function of fork length as: $TS_{max}=20log_{10}(FL)-60.35(R=0.92)$ and $TS_{avg.}=20log_{10}(FL)-66.89(R=0.88)$. These TS results for black seabream can be used for estimating the biomass of fish in acoustic surveys in coastal areas.

KOREA INSTITUTE FOR ADVANCED STUDY VALUE-ADDED GALAXY CATALOG

  • Choi, Yun-Young;Han, Du-Hwan;Kim, Sung-Soo S.
    • Journal of The Korean Astronomical Society
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    • v.43 no.6
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    • pp.191-200
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    • 2010
  • We present the Korea Institute for Advanced Study Value-Added Galaxy Catalog (KIAS VAGC), a catalog of galaxies based on the Large Scale Structure (LSS) sample of New York University Value-Added Galaxy Catalog (NYU VAGC) Data Release 7. Our catalog supplements redshifts of 10,497 galaxies with 10 < $r_P\;{\leq}\;17.6$ (1455 with 10 < $r_P\;{\leq}\;14.5$) to the NYU VAGC LSS sample. Redshifts from various existing catalogs such as the Updated Zwicky Catalog, the IRAS Point Source Catalog Redshift Survey, the Third Reference Catalogue of Bright Galaxies, and the Two Degree Field Galaxy Redshift Survey have been put into the NYU VAGC photometric catalog. Our supplementation significantly improves spectroscopic completeness: the area covered by the spectroscopic sample with completeness higher than 95% increases from 2.119 to 1.737 sr. Our catalog also provides morphological types of all galaxies that are determined by the automated morphology classification scheme of Park & Choi (2005), and related parameters, together with fundamental photometry parameters supplied by the NYU VAGC. Our catalog contains matches to objects in the Max Planck for Astronomy (MPA) & Johns Hopkins University (JHU) spectrum measurements (Data Release 7). This new catalog, the KIAS VAGC, is complementary to the NYU VAGC and MPA-JHU catalog.

Use of Leaf Size for Indirect Selection of Seed Size in Soybean (대두 종자크기에 대한 간접선발지표로써 잎 크기의 이용)

  • Chung, Jong-Il;Specht, James E.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.42 no.6
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    • pp.810-813
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    • 1997
  • The objective of this research was to determine if leaf size (width and length) is correlated with seed size to the extent that leaf size can be used as a predictor of seed size in a population of soybean plants or lines. Twelve soybean strains, representing three distinct seed size groups, were analyzed. Data on seed size and leaf size of the 12 strains were obtained in 1994 and 1995 field experiments. Strain seed size was positively associated with leaf width (r=0.918) and leaf length (r=0.925). The results of our study indicate that there is a significant correlation between seed size and leaf size in soybean. It is possible that selection for greater seed size either leads to, or results from, greater leaf size.

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Biosorption of Methylene Blue from Aqueous Solution using Dried Rhodotorula glutinis Biomass

  • Dae Haeng Cho;Jaesung Lee;Eui Yong Kim
    • Korean Chemical Engineering Research
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    • v.61 no.2
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    • pp.273-277
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    • 2023
  • The biosorption of methylene blue (MB) from aqueous solution was investigated using dried Rhodotorula glutinis as the biosorbent. The effects of pH, initial dye concentration, biosorbent dosage, and kinetic studies were determined to obtain valuable information for biosorption. Results indicated that most of the adsorbed MB bound within 30 minutes of contact and the MB adsorption capacity increased from 21.1 to 101.8 mg/g with the initial MB concentration increased from 50 to 300 mg/L. Additionally, the MB adsorption capacity gradually increased from pH 4.0 to 9.0, reaching its peak at an initial pH of 9.0. As the biomass load was increased from 0.25 to 4.0 g/L, the MB removal efficiency increased from 14.1 to 84.5%. The Langmuir model provided the best fit throughout the concentration range, and the maximum adsorption capacity (qmax) and Langmuir constant (b) were determined to be 135.14 mg/g and 0.026 l/mg, respectively. Furthermore, the biosorbent process of R. glutinis was found to follow pseudo-second-order kinetics and the calculated qeq,cal value showed good agreement with the experimental qeq value. Overall, the biosorption of MB by R. glutinis can be characterized as a monolayer, single site type phenomenon, and the rate-limiting step was determined to be the chemical reaction between the adsorbent and the adsorbate.

HIGHER DERIVATIVE VERSIONS ON THEOREMS OF S. BERNSTEIN

  • Singh, Thangjam Birkramjit;Devi, Khangembam Babina;Reingachan, N.;Soraisam, Robinson;Chanam, Barchand
    • Nonlinear Functional Analysis and Applications
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    • v.27 no.2
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    • pp.323-329
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    • 2022
  • Let $p(z)=\sum\limits_{\nu=0}^{n}a_{\nu}z^{\nu}$ be a polynomial of degree n and $p^{\prime}(z)$ its derivative. If $\max\limits_{{\mid}z{\mid}=r}{\mid}p(z){\mid}$ is denoted by M(p, r). If p(z) has all its zeros on |z| = k, k ≤ 1, then it was shown by Govil [3] that $$M(p^{\prime},\;1){\leq}\frac{n}{k^n+k^{n-1}}M(p,\;1)$$. In this paper, we first prove a result concerning the sth derivative where 1 ≤ s < n of the polynomial involving some of the co-efficients of the polynomial. Our result not only improves and generalizes the above inequality, but also gives a generalization to higher derivative of a result due to Dewan and Mir [2] in this direction. Further, a direct generalization of the above inequality for the sth derivative where 1 ≤ s < n is also proved.

Effects of acute reducing salt supplementation on cardio-respiratory function, blood pressure and serum nitric oxide production in elite players

  • Kim, Hag-Lyeol;Ueda, Hideo;Son, Yeon-Hee;Lee, Sam-Jun;Kim, In-Cheol
    • Korean Journal of Exercise Nutrition
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    • v.14 no.2
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    • pp.95-101
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    • 2010
  • The purpose of this study was to evaluate changes of body composition, cardio-respiratory function in ventilation threshold (VT) and maximal state exercise, systolic (SBP) and diastolic blood pressure (DBP) and serum nitric oxide (NO) production during acute reducing salt (RS) supplementation in college elite athletes. Variables of cardio-respiratory function during rest, ventilation threshold and maximal exercise was not shown a significantly difference between RS supplementation and non-supplementation, there was shown a significant increase in ventilation threshold time (p<0.05) and exhaustion time (p<0.05) during RS supplement compared to non-supplement. SBP and DBP were not shown a significant difference between RS supplement and non-supplement. This result suggests that acute intake of RS is not increased a blood pressure. Serum NO production was not significant difference in the RS supplement group, but it was shown a significantly increased levels (p<0.01, vs. recovery 30 min.) immediately after maximal exercise in the non-supplement group. This result suggests that acute intake of RS have important role in inhibition of serum NO production during maximal exercise. Conclusively, This study suggest that acute intake of RS was not influence in body composition variables, but it was positive effect in ventilation threshold time, exhaustion time, maintenance of blood pressure and inhibition of serum NO production in maximal treadmill exercise.