• Animal cells and systems
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• v.3 no.2
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• pp.215-219
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• 1999

Monoclonal antibody for delta-9-tetrahydrocannabiol (THC Ab), conjugated with protein A-gold, was employed as a probe to detect THC localization in the gland and subjacent cells of chemically fixed bracts of Cannabis. THC was detected in the outer wall of the disc cells, fibrillar matrix, the surface feature of secretory vesicles, and sheath throughout development of the secretory cavity. The probe was absent from vesicles. Label was also present in anticlinal walls of disc cells and walls of dermal and mesophyll cells. Little or no THC Ab was present in disc cells and none were detected in control tissues. This distribution pattern of THC Ab was similar to that in tissues prepared by high pressure cryofixation-cryosubstitution. Consistent association of THC with wall and wall-derived materials suggests that cannnabinoids are synthesized outside the plasma membrane and bound to a wall component, where-upon they are transported to the cavity with wall materials released from the disc cell wall during development of the secretory cavity.

• Journal of the Korean Chemical Society
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• v.44 no.3
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• pp.184-189
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• 2000

ab initio molecular orbitaI calculation is performed to estimate the substituent effects for meta-substituted pyridines. Electrostatic potentials are obtained from ab initio wavefunctions of the optimized structures for the meta-substituted pyridines. Electrostatic potenhals are shown to be minimum at nitrogen atom of pyridines. The potenttial minima are good correlated with the substituent constants, ${\sigma}_m$ and with the ${\Delta}pK_a$, respectively. It is found that the electrostatic potential minima can be used as a useful measure of substituent effects.

• Journal of Microbiology and Biotechnology
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• v.13 no.3
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• pp.400-405
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• 2003

A gene (hpkA), encoding a histidine protein kinase homolog, has been identified in the upstream region of the espAB operon in Myxococcus xanthus. It encodes a 333 amino acid (35,952 Da) protein with a histidine protein kinase domain in the region from amino acid 90 to 317. Null mutations in the hpkA gene caused formation of loose irregular fruiting bodies, while wild-type strains developed tight hemispherical fruiting bodies under developmental conditions. Sporulation of the hpkA mutant was delayed by at least 12 h compared to that of the wild-type. It appeared that the hpkA mutation increased the expression of the espAB operon by more than 2-fold compared with the wild-type under developmental conditions. Expression of the hpkA gene was low under vegetative conditions, but was highly induced under developmental conditions.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.43-46
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• 2008

This study investigated if a requirement for screen gloss is needed in the TCO Requirements and was, therefore, targeted towards finding an acceptable reflex level. The results show that a glossy surface has an impact on the visual ergonomics, and for this reason we believe that a requirement is needed. Although, the results do not point to a single value that is better than another, so a selection for a requirement level has to be augmented with additional information. Such a discussion is given and 60 gloss units at 60 degrees ($GU_{60}$) was selected as the new requirement level for the TCO Requirements (TCO '03 and TCO '05).

• Journal of Photoscience
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• v.6 no.4
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• pp.157-158
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• 1999

The conformational studies of glycinemethylester have been carried out by the ab initio method. We have optimized the geometries of glycinemethylester at various levels of sophisticated for electron exchange and correlation within MP2 level. The scale factors of glycinemethylester were used to obtain the scaled ab initio force field of the minimum energy conformer of it, which was used to predict the vibrational frequencies and their potential energy distribution. The Raman spectra of the glycinemethylester were compared with the observed one and the other calculated with HF/6-3IG level.

• Kyungpook Mathematical Journal
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• v.55 no.2
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• pp.473-484
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• 2015

Archimedes determined the center of gravity of a parabolic section as follows. For a parabolic section between a parabola and any chord AB on the parabola, let us denote by P the point on the parabola where the tangent is parallel to AB and by V the point where the line through P parallel to the axis of the parabola meets the chord AB. Then the center G of gravity of the section lies on PV called the axis of the parabolic section with $PG=\frac{3}{5}PV$. In this paper, we study strictly locally convex plane curves satisfying the above center of gravity properties. As a result, we prove that among strictly locally convex plane curves, those properties characterize parabolas.

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1177-1184
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• 2005

Ab initio quantum chemical molecular orbital calculations have been performed for the unimolecular decomposition of methacrylonitrile ($CH_3C(CN)=CH_2$), especially for HCN and $H_2$ molecular elimination channels. Structures and energies of the reactants, products, and relevant species along the individual reaction pathways were determined by MP2 gradient optimization and MP4 single point energy calculations. Direct four-center elimination of HCN and three-center elimination of H2 channels were identified. In addition, H or CN migration followed by HCN or H2 elimination channels via the methylcyanoethylidene intermediate was also identified. Unlike the case of crotonitrile previously studied, in which the dominant decomposition process was the direct three-center elimination of HCN, the most important reaction pathway should be the direct threecenter elimination of $H_2$ in the case of methacrylonitrile.

• 한국정보통신설비학회:학술대회논문집
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• 2008.08a
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• pp.403-408
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• 2008

In this paper, the high efficiency and linearity Doherty power amplifier using DGS and adaptive bias technique has been designed and realized for 2.3GHz WiBro applications. The Doherty amplifier has been implemented us-ing silicon MRF 281 LDMOS FET. The RF performances of the Doherty power amplifier (a combination of a class AB carrier amplifier and a bias-tuned class C peaking amplifier) have been compared with those of a class AB amplifier alone, and conventional Doherty amplifier. The Maximum PAE of designed Doherty power amplifier with DGS and adaptive bias technique has been 36.6% at 34.01dBm output power. The proposed Doherty power amplifier showed an improvement 1dB at output power and 7.6% PAE than a class AB amplifier alone.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.1031-1037
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• 2001

By a sequential action of ${\beta}$-ketothiolase and acetoacetyl-CoA reductase, two molecules of acetyl-CoA re converted into D-3-hydroxybutyryl-CoA, a substrate for PHB synthase to form poly-3-hydroxybutyryl-CoA, a substrate for PHB synthase to form poly-3-hydroxybutyrate (PHB) of rhodobacter sphaeroides. The ${\beta}$-ketothiolase gene, phbA, and acetoacetyl-CoA reductase gene, phbB, were cloned and analyzed for their expression. Enzyme activities of ${\beta}$-ketothiolase and acetoacetyl-CoA reductase showed constitutive levels during aerobic and photoheterotrophic growth of R. sphaeroides. In addition, no difference of each enzyme activity was observed between cells grown aerobically and photoheterotrophically. The constitutive level of the enzyme activities are regulated according to the growth phases along with growth conditions. Thus, phbAB expression is not determinative in regulating the PB content. On the other hand, phbA-deleted cell AZI accumulated only $10\%$ PHB of the wild-type, and an elevated dosage of phbAB in trans in R. sphaeroides resulted in a higher content of PHB, indicating that phbAB codes for the enzymes responsible for providing the main supply of subsyrate for PHB synthase. PHB formation by an alternative pathway that does not does not depend on the phbA-and phbB-coding enzymes is also proposed.

• Asian Journal of Atmospheric Environment
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• v.9 no.2
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• pp.158-164
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• 2015

The estimation of the concentration of hydroxyl radical (OH) in the atmosphere is essential to build atmospheric models and to understand the mechanisms of the reactions involved in OH. Although water vapor is one of the most abundant species in the troposphere, only a few studies have been performed for the reaction of OH and water vapor. Here I demonstrate an ab initio study on the complex forming reation of OH with $H_2O$ in the gas phase performed based on density functional theory to calculate the reaction rate and the energy states of the reactant and the OH-$H_2O$ complex. The structure of the complex, which belongs to the Cs point group, was optimized at global minima. The transition state was not found at the B3LYP and MP2 levels of theory. Rate constants of the forward and the reverse reactions were calculated as $1.1{\times}10^{-16}cm^3\;molecule^{-1}\;s^{-1}$ and $5.3{\times}10^9\;s^{-1}$, respectively. The extremely slow rates of complex forming reaction and the resulting hydrogen atom exchange reaction of OH and $H_2O$, which are consistent with experimentally determined values, imply a negligible possibility of a change in OH reactivity through the title reaction.