• Title/Summary/Keyword: CL-data

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The Chemical Constituents of the Stem Barks of Fraxinus rhynchophylla (물푸레나무(Fraxinus rhynchophylla) 수피의 추출성분)

  • Yang, Eun-Ju;Lee, Dong-Geun;Lee, Jong-Won;Kim, Yae-Sil;Lim, Sun-Ha;Song, Kyung-Sik
    • Applied Biological Chemistry
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    • v.50 no.4
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    • pp.348-351
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    • 2007
  • The stem barks of Fraxinus rhynchophylla was extracted with 95% EtOH, and the concentrated extract was successively partitioned with $CH_2Cl_2$, n-BuOH, and $H_2O$ in order to investigate the major phytochemicals. From the $CH_2Cl_2$ soluble fraction, a sterol (1) was isolated through the repeated silica gel column chromatographies. Three additional compounds (2-4) were isolated from the n-BuOH soluble fraction through silica gel, RP-18, and Sephadex LH-20 column chromatographies. Their chemical structures were elucidated as daucosterol $(1;{\beta}-sitosterol-3-O-{\beta}-D-glucopyranoside)$, caffeic acid (2), 6,8-dihydroxy-7-methoxycoumarin (3), and coniferaldehyde glucoside (4) by comparing their spectral data with those in the literatures. All isolates (1-4) were the first to be isolated from F. rhynchophylla.

Factors Influencing Smartphone Addiction in Adolescents (청소년의 스마트폰 중독에 영향을 미치는 요인)

  • Lee, Eun Jee;Kim, Yune Kyong;Lim, Su-Jin
    • Child Health Nursing Research
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    • v.23 no.4
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    • pp.525-533
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    • 2017
  • Purpose: The purpose of this study was to verify the relationship among depression, school adjustment, parent-child bonding, parental control and smartphone addiction, and to identify factors which influence smartphone addiction in adolescents. Methods: A cross-sectional design was used, with a convenience sample of 183 middle school students from 3 middle schools. Data collection was conducted through self-report questionnaires from April to May, 2017. Data were analyzed using ${\chi}^2$ test, Fisher's exact test, t-test, one-way ANOVA, correlation coefficient analysis, and binary logistic regression with SPSS Ver. 21.0. Results: The mean score for smartphone addiction was 29.40. Of the adolescents, 21.3% were in the smartphone addiction risk group. Logistic regression analysis showed that gender (OR=7.09, 95% Cl: 2.57~19.52), school life (OR=0.86, 95% Cl: 0.79~0.93), smartphone usage time (OR=1.32, 95% Cl: 1.04~1.66), and parental control (OR=4.70, 95% Cl: 1.04~21.29) were effect factors for the smartphone addiction risk group. Conclusion: Findings indicate that school satisfaction was an important factor in adolescents' smartphone addiction. Control oriented parent management of adolescents' smartphone use did not reduce the risk of smartphone addiction and may have worsen the addiction. Future research is needed to improve understanding of how teachers and parents will manage their adolescents' use of smartphones.

Kinetic Analysis of the Hepatic Uptake and Biliary Excretion of 1-Anilino-8-Naphthalene Sulfonate (ANS) in Vivo (In Vivo 레벨에서 1-아닐리노-8-나프탈렌 설포네이트(ANS)의 간내 이행 및 담즙배설 과정의 속도론적 해석)

  • Bae, Woong-Tak;Chung, Youn-Bok;Han, Kun
    • Journal of Pharmaceutical Investigation
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    • v.31 no.4
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    • pp.209-216
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    • 2001
  • The purpose of the present study was to investigate the hepatic uptake and biliary excretion of l-anilino-8-naphthalene sulfonate (ANS) in vivo. The plasma concentration and liver concentration of ANS were determined after its i.v. bolus administration at a dose of $30\;{\mu}mol/kg$ in rats. The hepatic uptake clearance $(CL_{uptake})$ of ANS was 0.1 ml/min/g liver. On the basis of the unbound concentration of ANS, the permeability-surface area product $(PS_{influx})$ was calculated to be l0.4 ml/min/g liver, being comparable of in vitro data. On the other hand, we determined the plasma concentration, liver concentration and biliary excretion rate of ANS at steady-state after its i. v. infusion $(0.2-1.6\;{\mu}mol/min/kg)$ in rats. The excretion clearance $(CL_{excretion})$ of ANS showed Michaelis-Menten kinetics with increasing the infusion rate. The permeability-surface area product $(PS_{excretion})$ based on the unbound concentration in the liver was calculated to be 0.0165 ml/min/g liver, which is negligible compared with the intrinsic clearance $(CL_{int}=3.3\;ml/min/g\;liver)$ by rat liver microsomes. The sequestration process of ANS, therefore, was considered to be mainly due to the metabolic process in the liver $(PS_{seq}{\risingdotseq}CL_{int})$. Furthermore, $PS_{efflux}$ value calculated from $PS_{influx}$ and $PS_{seq}$ was 4.4 ml/min/g liver, which was comparable of in vitro data. In conclusion, in vivo parameters such as $PS_{influx}$, $PS_{efflux}$ and $PS_{seq}$ in the present study showed good in vivo-in vitro relationship. Thus, the kinetic analysis method proposed in the present study would be useful to analyze the hepatic transport of drugs in vivo.

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Synthesis and Characterization of a Novel Organotin Complex: Di(n-butyl) chloro[5-(p-dimethylaminobenzylidene)rhodanine]tin(IV) Based on a Competing N, O, and S Donor Ligand (새로운 유기주석 착물의 합성과 특성: 경쟁적인 N, O 및 S 주개 리간드에 기초한 Di(n-butyl)chloro[5-( p-dimethylaminobenzylidene)rhodanine]tin(IV))

  • Tarassoli, Abbas;Sedaghat, Tahereh;Mousavi, Fatemeh
    • Journal of the Korean Chemical Society
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    • v.55 no.4
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    • pp.590-593
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    • 2011
  • A novel organotin(IV) complex has been prepared from $Bu_2SnCl_2$ and the N, O and S donor ligand, 5-(p-dimethylaminobenzylidene) rodanine (HL). The ligand is deprotonated in the presence of a base and the complex with the general formula $SnBuCl_2L$ is formed. This complex was fully characterized by IR, $^1H$ NMR and $^{119}Sn$ NMR and elemental analysis. Spectroscopic data indicate the ligand is coordinated through the oxygen atom to the tin and the coordination number of four is supported by $^{119}Sn$ NMR data in solution.

Theoretical Study of the Isotope Effect for the Reaction Cl+HD at the High Energy Using Pairwise Energy Model (Pairwise Energy Model을 이용한 높은 충돌에너지에서 Cl+HD 반응의 동위원소 효과에 대한 이론적 연구)

  • Ju-Beom Song
    • Journal of the Korean Chemical Society
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    • v.47 no.3
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    • pp.191-198
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    • 2003
  • The pairwise energy model (PEM) assumes that the cross section for the reaction cross section for the reaction A+BC$\{leftrightarrow}$B+C, where B and C are isotopes of hydrogen, depends on only the pairwise relative energy Es between A and B. Until now, the PEM has been used to interpret theoretically the isotope effect for the reactions such as $O(^3P)+HD,\;Ar^++(H_2,\;D_2,and\;HD)$. In this paper we carry out extensive quasiclassical trajectory calculations for the three possible reactions $Cl+H_2$ and HD and show that the PEM works very well at high energy. In particular we are able to accurately predict the intramolecular isotope effect at high energy for the reaction of Cl+HD using only the cross section data for $Cl+H_2$. To understand that the PEM works so well at high energy, the internal energy distributions for the products are examined. The distributions for three reactions are different at a fixed relative collision energy E but are approximately same at a fixed pairwise energy Es. This suggests that the PEM works very well at high energy. We believe the conclusions reached here will apply to other A+BC systems.

Kinetics and Mechanism for Aquation of $[Co(en)_2Cl_2]^+$ in the $Hg^{2+}$ Aqueous Solution ($Hg^{2+}$수용액에서 $[Co(en)_2Cl_2]^+$의 아쿠아 반응속도론과 메카니즘)

  • Byung-Kak Park;Joo-Sang Lim;Sung Nak-Jung;Il-Bong Lee;Kwang-Jin Kim;Sung-Gu Kang
    • Journal of the Korean Chemical Society
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    • v.32 no.4
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    • pp.342-350
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    • 1988
  • An experimental investigation is made to determine the mechanism of the aquation of $[Co(en)_2Cl_2]^+$ in $Hg^{2+}$ aqueous solution. The progress of reaction is followed UV/vis-spectrophotometrically by a measurment of the absorbance at a specific wavelength of Co(III) complex as a function of time. The aquation of cis-$[Co(en)_2Cl_2]^+$ and trans-$[Co(en)_2Cl_2]^+$ has been found to be first order and second order with respect to the concentration of $Hg^{2+}$ catalyst, respectively. It has been found that the reaction rate for aquation of the trans-form is faster than that of cis-form, and that the product of either cis-form or trans-form is always in the mixture ratio of 97 % to 3 %. Plausible reaction mechanism is proposed for the reaction system on the basis of kinetic data and activation parameters. Theoretical rate equation derived from the proposed mechanism is consistent with the observed one.

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${\gamma}$-Aminobutyric Acid Production and Glutamate Decarboxylase Activity of Lactobacillus sakei OPK2-59 Isolated from Kimchi (김치유래 Lactobacillus sakei OPK2-59의 ${\gamma}$-Aminobutyric Acid 생성 및 Glutamate Decarboxylase 활성)

  • Yu, Jin-Ju;Oh, Suk-Heung
    • Korean Journal of Microbiology
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    • v.47 no.4
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    • pp.316-322
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    • 2011
  • Lactobacillus sakei OPK2-59 isolated from kimchi was found to have ${\gamma}$-aminobutyric acid (GABA) producing ability and glutamate decarboxylase (GAD) activity. When the Lactobacillus sakei OPK2-59 was cultured in MRS broth with 59.13 mM and 177.40 mM monosodium glutamate (MSG), the optimum temperature range and pH for growth were $25-37^{\circ}C$ and pH 6.5, respectively. GABA conversion rates in MRS broth with 59.13 mM and 177.40 mM MSG were 99.58% and 31.00%, respectively at $25^{\circ}C$ and 48 h of cultivation. By using the cell free extract of Lactobacillus sakei OPK2-59, MSG was converted to GABA and the conversion rate was 78.51% at $30^{\circ}C$, pH 5. Conversion of MSG to GABA was enhanced by adding salts such as $CaCl_2$, $FeCl_3$, $MgCl_2$. These data suggest that the ability of Lactobacillus sakei OPK2-59 to produce GABA results from the activity of GAD in the cells and GABA conversion by the cell extract containing GAD can be enhanced by $CaCl_2$, $FeCl_3$, $MgCl_2$.

Design of Software GPS L2 Civil Signal Generator (ICCAS 2003)

  • Seo, Sam-Suk;Cho, Deuk-Jae;Lee, Sang-Jeong
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.2632-2635
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    • 2003
  • This paper designs a software signal generator for the new GPS L2 civil signal. The CM/CL code and the message structure of L2CS described in GPS ICD PPIRN-200C-007 are used in designing the signal generator. The output of the GPS signal generator is designed as the sampled IF data with the sampling frequency 5.7MHz and stored in the binary data format. By analyzing both the spectrum characteristics of the output signal and the correlation properties of the CM/CL code, the validation of the designed GPS signal generator is shown. It should be mentioned that the modeling of the GPS satellite constellation and the error sources remains for implementing the software space segment of GPS.

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Tool interference check in machining of large screws defined by cross-section view (축 수직단면 형상정의에 대한 대형 스크류의 가공시 공구간섭검사)

  • 안중환
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.9 no.3
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    • pp.169-177
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    • 2000
  • In machining screws which are important members in mono pumps or progressive cavity pumps CNC turning center with 3 axes is usually used. This sort of screw machining requires large amount of CL data points and rotational tools are used in machining. When working out the CL data points consideration of possible tool interference is important in order to avoid undercut. This paper describes the checking methods of tool interference in the screw machining on the CNC turning center. First of all a specific shape of a screw cross-section that could commonly be applied to all screws was chosen and then possible tool interference associated with that shape was identified. Checking method was mathematically developed and verified. This checking method will be utilized in the CAM system developed by the authors for screw machining on the 3-axis CNC turning center.

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