• YAKHAK HOEJI
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• v.54 no.6
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• pp.466-473
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• 2010

A series of $3{\beta}$-substituted 5-androstene-$17{\beta}$-carboxamides were synthesized from analogs of $3{\beta}$-hydroxy-5-androstene-$17{\beta}$-carboxylic acid (1) with tert-butylamine, N,N-diethylamine and 3-aminopyridine and some compounds were epoxidized with mCPBA. A rat prostate testosterone $5{\alpha}$-reductase inhibitory activity of synthesized compounds was assessed by radioimmunoassay using [1,2,6,7-3H]-testosterone as substrate. All synthesized compounds showed lower activity than finasteride and the N-(3-pyridino)-$3{\beta}$-carboxycarbonyloxy-5-androstene-$17{\beta}$-carboxamide (12) showed weak inhibitory activity ($IC_{50}$: $2.4{\times}10^{-7}M$).

• KSBB Journal
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• v.6 no.1
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• pp.111-114
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• 1991

The effects of the precursor processing inhibitor, carbonylcyanide-chlorophenyl hydrazone(CCCP), are investigated on the production of soluble ${\beta}-lactamase$ the formation of the inclusion body when ${\beta}-lactamase$ is overproduced by induction with isopropyl thiogalactoside(IPTG). When cells are treated by CCCP, more soluble ${\beta}-lactamase$ is produced. In this case, no difference in the amount of inclusion body is observed.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.575-579
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• 1991

Reaction of 6${\beta}$-bromopenicillanic acid(4a) with p-nitrobenzylbromide, 3-bromophthalide, chloromethylpivalate and 1-chlorodiethylcarbonate afforded 6${\beta}$-bromopenicillanates(4b~4e). New ${\beta}$-lactam compound, 6-(carboxymethylthio)penicillanic acid(5a) and the other esters(5b~5e) were prepared by nucleophilic substitution reaction of 6${\beta}$-bromopenicillanic acid(4a) and the other esters(4b~4e) with thioglycolic acid.

• Journal of Sensor Science and Technology
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• v.25 no.5
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• pp.333-336
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• 2016

In this study, a beta monitoring sensor was developed as a part of basic research for quantitative beta monitoring underwater, and its performance was evaluated using a calibration source. A beta detection sensor was manufactured by using SiPM(silicon photomultiplier) and $CaF_2$:Eu, YAG:Ce, YAP:Ce scintillator. A large-area light guide was introduced to improve beta-ray detection efficiency. As calibration sources, the Beta source $^{90}Sr$, which is the main fission product of a nuclear accident, and the gamma source $^{137}Cs$ are used. In the performance evaluation, it is confirmed that scintillator $CaF_2:Eu$ gives the highest beta-ray detection response. Compared to gamma ray, beta-ray detection responsivity and detection efficiency are verified. Therefore, this study is expected to contribute to basic research in the development of an underwater beta-ray monitoring system.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.185-189
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• 2009

Microencapsulation of flavor was carried out by molecular inclusion process using $\beta$-cyclodextrin (${\beta}CD$). ${\beta}CD$-flavor complex was prepared at various flavor-to-${\beta}CD$ ratios (1:6-1:12) to determine the effect of ${\beta}CD$ concentration on the inclusion efficiency. Maximum total oil retention and minimal surface oil content were obtained at flavors to ${\beta}CD$ ratio of 1:10. The physical properties and controlled release pattern of flavors from ${\beta}CD$-flavor complex were measured and compared with spray-dried microcapsules prepared using carbohydrate wall system. ${\beta}CD$-flavor complex showed higher total oil retention and surface oil contents, smaller mean particle size, lower moisture uptake, and higher oxidation stability than spray-dried microcapsule. Oxidative stability of flavor was correlated with hygroscopicity of wall materials. The controlled release mechanism was highly affected by temperature and characteristics of wall materials.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.05a
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• pp.154-157
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• 2000

In this paper, we propose a method for vehicle tracking systems using fuzzy logic. The standard ${\alpha}$-${\beta}$ filter estimates the future target positions using fixed ${\alpha}$,${\beta}$ coefficients. We utilize the if-then fuzzy logic to make ${\alpha}$ and ${\beta}$ coefficients vary with the position. Comparisons are made in tracking vehicles using three different schemes: the standard ${\alpha}$-${\beta}$ filter, ${\alpha}$-${\beta}$ filter using fuzzy logic, and the Kalman filter.

• Journal of Yeungnam Medical Science
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• v.35 no.1
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• pp.1-6
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• 2018

Alzheimer's disease (AD) is a neurodegenerative disorder associated with extracellular plaques, composed of amyloid-beta ($A{\beta}$), in the brain. Although the precise mechanism underlying the neurotoxicity of $A{\beta}$ has not been established, $A{\beta}$ accumulation is the primary event in a cascade of events that lead to neurofibrillary degeneration and dementia. In particular, the $A{\beta}$ burden, as assessed by neuroimaging, has proved to be an excellent predictive biomarker. Positron emission tomography, using ligands such as $^{11}C$-labeled Pittsburgh Compound B or $^{18}F$-labeled tracers, such as $^{18}F$-florbetaben, $^{18}F$-florbetapir, and $^{18}F$-flutemetamol, which bind to $A{\beta}$ deposits in the brain, has been a valuable technique for visualizing and quantifying the deposition of $A{\beta}$ throughout the brain in living subjects. $A{\beta}$ imaging has very high sensitivity for detecting AD pathology. In addition, it can predict the progression from mild cognitive impairment to AD, and contribute to the development of disease-specific therapies.

• Bulletin of the Korean Chemical Society
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• v.15 no.9
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• pp.795-799
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• 1994

Kinetic studies of the deacylation reactions of p-and m-nitrophenyl esters of (R or S)-${\alpha}$ -methoxyphenylacetic acid were performed in ${\beta}$ -CD, mono-6-deoxy-6-[N-(2-aminoethyl)]amino-${\beta}$-CD (${\beta}$-CDen) and mono-6-deoxy-6-[N-(2-aminoethyl)-2-aminoethyl] amino-${\beta}$-CD (${\beta}$-CDdien) media. The binding constants (K) of the substrates to the hosts and the rate constants ($k_{\varphi}^{CD}$) for the complexed substrates were determined. $k_{\varphi}^{CD}$ values are highly dependent on the hosts and the substrates, whereas differences in K values among them are modest. The p-nitrophenyl esters show larger acceleration by -${\beta}$-CDen and -${\beta}$-CDdien than the corresponding m-isomers, while the m-isomers are more reactive than the p-isomers in -${\beta}$-CD media. This is taken as an indication that the amino groups attached to the primary side of -${\beta}$-CD participate in the deacylation reaction.

• Archives of Pharmacal Research
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• v.27 no.1
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• pp.57-60
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• 2004

Glycyrrhizin (18$\beta$-glycyrrhetinic acid-3-O-$\beta$-D-glucuronopyranosyl-(1$\rightarrow2)-\beta$-D-glucuronide, GL) was transformed to 18$\beta$-glycyrrhetinic acid-3-O-$\beta$-D-glucuronide (GAMG) by Streptococcus LJ-22. The antiallergic activities of GL and GAMG was measured using a RBL cell assay system and contact hypersensitivity model mice. GAMG exhibited anti-allergic activity with $IC_{50}$ values of 0.28 mM. GAMG, which is sweeter than GL, and 18$\beta$-glycyrrhetinic acid, which is a GAMG metabolite by human intestinal bacteria, also inhibited the passive cutaneous anaphylaxis and skin contact inflammation. In conclusion, GAMG may be useful as a new sweet food additive and an anti-allergic agent.

• Bulletin of the Korean Mathematical Society
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• v.56 no.5
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• pp.1117-1127
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• 2019

Let ${\mathcal{L}}_2=(-{\Delta})^2+V^2$ be the $Schr{\ddot{o}}dinger$ type operator, where nonnegative potential V belongs to the reverse $H{\ddot{o}}lder$ class $RH_s$, s > n/2. In this paper, we consider the operator $T_{{\alpha},{\beta}}=V^{2{\alpha}}{\mathcal{L}}^{-{\beta}}_2$ and its conjugate $T^*_{{\alpha},{\beta}}$, where $0<{\alpha}{\leq}{\beta}{\leq}1$. We establish the $(L^p,\;L^q)$-boundedness of operator $T_{{\alpha},{\beta}}$ and $T^*_{{\alpha},{\beta}}$, respectively, we also show that $T_{{\alpha},{\beta}}$ is bounded from Hardy type space $H^1_{L_2}({\mathbb{R}}^n)$ into $L^{p_2}({\mathbb{R}}^n)$ and $T^*_{{\alpha},{\beta}}$ is bounded from $L^{p_1}({\mathbb{R}}^n)$ into BMO type space $BMO_{{\mathcal{L}}1}({\mathbb{R}}^n)$, where $p_1={\frac{n}{4({\beta}-{\alpha})}}$, $p_2={\frac{n}{n-4({\beta}-{\alpha})}}$.