• Title/Summary/Keyword: ${\alpha}_s$-method

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Studies on Inclusion Compounds of Suprofen with Cyclodextrins (Suprofen과 Cyclodextrin과의 포접화합물(包接化合物)에 관(關)한 연구(硏究))

  • Han, Soon-Young;Yong, Jae-Ick
    • Journal of Pharmaceutical Investigation
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    • v.15 no.3
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    • pp.130-139
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    • 1985
  • Inclusion compounds of suprofen with ${\alpha}-$ and, ${\beta}-cyclodextrins\;({\alpha}-CyD,\;{\beta}-CyD)$ were studied in comparison with suprofen alone and commercial suprofen capsules. Inclusion compound formations of suprofen with ${\alpha}-$, and ${\beta}-CyDs$ in aqueous solution and in solid state were confirmed by UV absorption, circular dichroism spectroscopies, IR spectroscopy, differential scanning calorimetry and X-ray diffraction measurements. Solid inclusion complexes were prepared by freeze-drying method, and their molar ratios were found to be 1 : 1. The dissolution rate of inclusion complexes of suprofen with CyDs was notably higher than that of suprofen alone.

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In vivo evidence for brain-to-blood efflux transport of taurine and regulation of this transport by tumor necrosis factor-$\alpha$ at the blood-brain barrier

  • Lee, Na-Young;Kang, Young-Sook
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.69.2-69.2
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    • 2003
  • The purpose of this study is to examine whether the efflux system for taurine from brain to blood is present on the blood-brain barrier (BBB) using the brain efflux index (BEl) method and taurine transport system is regulated by CNS cell damage with oxidative stress agent such as diethyl maleate (DEM) or tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in vivo. [$^3$H]Taurine was microinjected into parietal cortex area 2 (Par2) of the rat brain, and was eliminated from the brain with efflux transport rate of 1.22 10$\^$-2//min, and the process is saturable with a $K_{m}$ of 43.5 ${\mu}$M. (omitted)

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The Feacture Extraction of Background EEG in the Time Domain by LS Prony Method. (LS Prony에 의한 시간영역에서의 배경뇌파 특징추출)

  • Ju, Dae-Seong;Hwang, Su-Yong;Choe, Gap-Seok
    • Journal of Biomedical Engineering Research
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    • v.10 no.2
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    • pp.131-138
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    • 1989
  • In this paper the feature of background EEG is extracted by LS Prony Method for the analysis of background EEG in the time domain. Autocorrelation leg estimates are not required with the LS Prony method. The Prony method is required any the solution of two serfs of simultaneous linear equation and a polynominal rooting. That the optimal order of this model is the 6-th order is determined by using Akaike' s Information Criterial test. From the experimential results the alpha band amplitude is the largest among alpha band beta band theta band delta band and beta band amplitude is larger than that of the delta band and theta band. The sustained time for the alph a band, the beta band, the delta band and the theta band is 2, 3461 (sec), 0.6490(sec), 0.3120(sec), 0.7046(sec) respectively. Consequenty the alpha band is maintained in the whole subjects, the beta band, the delta band, the theta band are existed intermittently in each subjects.

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Antimicrobial Activity of Bamboo(Phyllostachys bambusoides) Essential Oil (대나무 기름의 항균효과)

  • 이숙경
    • Journal of Food Hygiene and Safety
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    • v.15 no.1
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    • pp.55-59
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    • 2000
  • In order to develop a antimicrobial agent, dried bamboo trunk was extracted by high temperature suction and then antimicrobial activities against Staphylococcus aureus ATCC 2825 and Escherichia coli DH 5$\alpha$ were investigated as compared with tea tree oil and BHA. The minimal inhibitory concentrationo(MIC) of the extracted substance against microorganisms were also examined. The results are as follows: 1. By disc diffusion method, BHA showed the strongest antimicrobial activity on Gram-positive bacteria such as S. aureus ATCC 2825 but bamboo essential oil showed the strongest antimicrobial activity on Gram-negative bacteria such as E. coli DH 5$\alpha$. 2. By broth dilution method, the minimum inhibitory concentration of the BHA, tea tree oil and bamboo oil were not detected against S. aureus ATCC 2825(MIC, 6.0 $\mu$l/ ml) and E. coli DH 5$\alpha$(MIC, 6.0 $\mu$l/ ml)

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Determination of Reactivities by Molecular Orbital Theory (V). Sigma Molecular Orbital Treatment of $S_N$ Reactivities of Alkylchlorides. (화학반응성의 분자궤도론적 연구 (제5보). 염화알킬의 친핵성치환 반응성에 대한 시그마 분자궤도론적 연구)

  • Ikchoon Lee;Bon-Su Lee;Kwang-Su Kim
    • Journal of the Korean Chemical Society
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    • v.17 no.2
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    • pp.95-104
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    • 1973
  • Ground electronic structures and SNreactivities of a series of alkylchlorides (methyl,ethyl, iso-propyl, trans n-butyl, sec-butyl, tert-butylchloride) have been studied using approximate $({\sigma}-MO)$ method, such as EHT and CNDO/2. It was found that CNDO/2 gives better results for the systems such as alkylchlorides whose structural differences are not remarkable, in comparison with EHT method. According to CNDO/2 results, calculated dipole moments for alkylchlorides are slightly higher than observed values, showing the order of primary < secondary < tertiary alkylchlorides. It was also found that highest occupied(HO) MO's are completely or nearly degenerate, and show relatively weak $\pi$-antibonding nature between$\alpha$-carbon and Cl atoms. Furthermore, the electrons in this MO are largely confined to Cl atom, and hence these behaves as likely as p-lone pair electrons of Cl atom. On the contrary, lowest unoccupied (LU) MO's show strong $\sigma$-antibonding nature between $\alpha$-carbon and Cl atoms whose electron clouds are directed along the C-Cl axis. It has been discussed that the$S_N2$ reactivities of alkylchlorides may largely be controlled by ${\sigma}^{\ast}$ LUMO, and the antibonding strength between $\alpha$-carbon and Cl atoms in this MO may become the measure of $S_N2$reactivity. The relationship between $S_N2$reactivity and C-Cl bond polarizability has also been discussed. It has been suggested that the unique structure factors determining $S_N1$reactivities may be $\pi$-antibonding strength between $\alpha$-carbon and Cl atoms in HOMO and C-Cl bond strength in ground state.

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Electrophoretic Study of Serum Protein Changes in Pregnancy (정상임부(正常姙婦)의 혈청단백분획량(血淸蛋白分劃量)의 변동(變動)에 관(關)한 연구(硏究))

  • Tchai, B.S.;Park, J.B.;Cho, K.H.;Kim, H.C.
    • Journal of Nutrition and Health
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    • v.7 no.4
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    • pp.33-37
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    • 1974
  • Changes in the concentration of total protein, albumin, ${\alpha}_1-,{\alpha}_2-,{\beta}-,$ and ${\gamma}-globulin$ in Serum from 138 healthy, normal pregnant woman were studied by the method of cellulose-acetate electrophoresis. 1. The concentration of total serum protein decreased gradually during the first 7 month, and showed a tendency to increase thereafter. 2. The concentration of serum albumin showed a steady continuous fall untill term. 3. During pregnancy,${\alpha}_1$ and ${\beta}-globulin$ value rose, ${\gamma}-globulin$ value fell and ${\alpha}_2-globulin$ value showed no significant change.

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Determination of Branched-Chain α-Keto Acid Dehydrogenase Activity in Rat Tissues

  • Kim, Hyun-Sook;Johnson, Wayne A.
    • BMB Reports
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    • v.28 no.1
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    • pp.12-16
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    • 1995
  • The branched-chain ${\alpha}$-keto acid dehydrogenase (BCKAD) complex is a rate limiting enzyme which catalyzes the oxidative decarboxylation of branched-chain ${\alpha}$-keto acids. Numerous studies have suggested that BCKAD is subject to covalent modification in vitro via phosphorylation and dephosphorylation, which are catalyzed by a specific kinase and phosphatase, respectively. The biggest difficulty in the assay of BCKAD activity is to arrest the interconversion between the active and inactive forms. BCKAD activity was determined from fresh rat heart and liver tissues using homogenizing and assay buffers containing inhibitors of phosphatase and kinase. The results suggest that a radiochemical assay using ${\alpha}$-keto[1-$^{14}C$]-isovalerate as a substrate for the enzyme can be applied as a reliable method to determine in vitro enzyme activity with arrested interconversion between the active and inactive forms of the BCKAD complex.

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Molecular Characterization of Fusarium proliferatum Causing Leaf Blight Symptoms on Chinese chive (Allium tuberosum) in Korea

  • Kim, Kyong-Han;Lee, Seung-Yeol;Back, Chang-Gi;Jung, Hee-Young
    • Current Research on Agriculture and Life Sciences
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    • v.31 no.4
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    • pp.245-249
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    • 2013
  • In 2008, leaf blight symptoms were observed on several Chinese chive farms in Sangju. The Pathogenicity of the isolate was confirmed by artificial inoculation, where the pathogen exhibited a strong pathogenicity toward healthy plants. Morphological classification identified the isolate as from the Fusarium genus. For further analysis, PCR and phylogenetic classification were performed with ITS region and 28S rRNA gene which are commonly used for fungal identification. However, the results provided a poor resolution. To solve this problem, we analyzed translation elongation factor 1-alpha (TEF-$1{\alpha}$) gene. The analyzed results using TEF-$1{\alpha}$ gene indicated that the isolate was F. proliferatum. Therefore, it is assumed that TEF-$1{\alpha}$ gene is important when Fusarium sp. was identified using molecular classification method.

Magnetic Property of α-Fe2O3 Nanoparticles Prepared by Sonochemistry and Take-off Technique

  • Koo, Y.S.;Yun, B.K.;Jung, J.H.
    • Journal of Magnetics
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    • v.15 no.1
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    • pp.21-24
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    • 2010
  • A new synthetic method for the formation of uniform $\alpha-Fe_2O_3$ nanoparticles was reported and their magnetic properties were investigated. The sonochemical synthesis and the subsequent take-off technique resulted in spherical shaped $\alpha-Fe_2O_3$ nanoparticles with an average diameter of 60 nm. The temperature- and applied magnetic field-dependent magnetization of the $\alpha-Fe_2O_3$ nanoparticles was explained by the sum of two contributions, i.e., the Morin transition and superparamagnetism, because the critical size for superparamagnetism was within the size variation of the nanoparticles.

The Kinetics of Radical Copolyerization of ${\alpha}$-Methylstyrene with Acrylonitrile in a CSTR (연속반응기에서 ${\alpha}$-Methylstyrene과 Acrylonitrile 라디칼 공중합 속도론)

  • Kim, Nam-Seok;Park, Keun-Ho
    • Journal of the Korean Applied Science and Technology
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    • v.19 no.1
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    • pp.33-42
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    • 2002
  • Copolymerization of ${\alpha}$-Methylstyrene(AMS) with Acrylonitrile(AN) was carried out with benzoylperoxide(BPO) as an initiator in toluene at $80^{\circ}C$ in a continuous stirred tank reactor. Reaction volume and residence time were 0.6 liters and 3 hours, respectively. The monomer reactivity ratios, $r_{AMS}$ and $r_{AN}$ determined by both the Kele$T{\"{u}}d\"{o}s$ method and the Fineman-Ross method were $r_{AMS}$=0.16(0.14), $r_{AN}$=0.04(0.06). The cross-termination factor ${\Phi}$ of the copolymer over the entire AMS composition ranged from 0.75 to 0.92. The ${\Phi}$ factors of poly(AMS-co-AN) were increased with increasing AMS content. The simulated conversions and copolymerization rates were compared with the experimental results. It was observed that the average time to reach dynamic steady-state was three times the residence time.