• Journal of Astronomy and Space Sciences
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• 제30권3호
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• pp.163-168
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• 2013

Parameters associated with solar minimum have been studied to relate them to solar activity at solar maximum so that one could possibly predict behaviors of an upcoming solar cycle. The number of active days has been known as a reliable indicator of solar activity around solar minimum. Active days are days with sunspots reported on the solar disk. In this work, we have explored the relationship between the sunspot numbers at solar maximum and the characteristics of the monthly number of active days. Specifically, we have statistically examined how the maximum monthly sunspot number of a given solar cycle is correlated with the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days for the corresponding solar cycle. We have calculated the linear correlation coefficient r and the Spearman rank-order correlation coefficient $r_s$ for data sets prepared under various conditions. Even though marginal correlations are found, they turn out to be insufficiently significant (r ~ 0.3). Nonetheless, we have confirmed that the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days is less steep when solar cycles belonging to the "Modern Maximum" are considered compared with rests of solar cycles. We conclude, therefore, that the slope of the linear relationship between monthly sunspot numbers and the monthly number of active days is indeed dependent on the solar activity at its maxima, but that this simple relationship should be insufficient as a valid method to predict the following solar activity amplitude.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2675-2679
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• 2013

Activity-directed isolation of the methylene chloride fraction from the stems of Parthenocissus tricuspidata have led to the identification of two new compounds (1-2): 1-(2',3',5'-trihydroxyphenyl)-2-(4"-hydroxyphenyl)-ethane-1,2-(E)-epoxide (1, tricuspidatin A) and erythro-1-(3',5'-dihydroxyphenyl)-2-(4"-hydroxyphenyl)-ethane-1,2-diol (2, tricuspidatin B), together with four known compounds (3-6): ${\beta}$-sitosterol (3), nonacosan-1-ol (4), 3-(4-hydroxy-3-methoxyphenyl)-2-propenoic acid hexacosyl ester (5) and betulinic acid (6). Their chemical structures were elucidated based on spectroscopic (IR, UV, MS, 1D and 2D NMR) and physicochemical analyses. Compounds 1 and 2 showed strong DNA topoisomerase II inhibitory activity at both concentrations of 20 and $100{\mu}M$. In addition, 3 exhibited strong cytotoxic activity against the HT-29 and HepG2 cancer cell lines, and 6 showed strong cytotoxicity against the HT-29 and MCF-7 ones.

• Molecules and Cells
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• 제39권11호
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• pp.827-833
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• 2016

Regulator of calcineurin 1 (RCAN1) binds to calcineurin through the PxIxIT motif, which is evolutionarily conserved. SP repeat phosphorylation in RCAN1 is required for its complete function. The specific interaction between RCAN1 and calcineurin is critical for calcium/calmodulin-dependent regulation of calcineurin serine/threonine phosphatase activity. In this study, we investigated two available deletion rcan-1 mutants in Caenorhabditis elegans, which proceed differently for transcription and translation. We found that rcan-1 may be required for calcineurin activity and possess calcineurin-independent function in body growth and egg-laying behavior. In the genetic background of enhanced calcineurin activity, the rcan-1 mutant expressing a truncated RCAN-1 which retains the calcineurin-binding PxIxIT motif but misses SP repeats stimulated growth, while rcan-1 lack mutant resulted in hyperactive egg-laying suppression. These data suggest rcan-1 has unknown functions independent of calcineurin, and may be a stimulatory calcineurin regulator under certain circumstances.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.529-532
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• 2001

Korean food waste, one of the abundantly available but environmentally problematic organic wastes in Korea, was utilized as solid-substrate by fungal strain Aspergillus niger ATcC 6275 for the production of enzymemixture containing amylase, cellulase and xylanase. The enzyme mixture can be used as high value-added animal feed. Solid-state fermentation method yielded a 84-fold enhancement in xylanase activity compared with submerged fermentation method. The effect of incubation period, incubation temperature, pH of medium, moisture content, inoculum size and enrichment of the medium with nitrogen and carbon sources were observed for optimal production of these enzymes The optimal amylase activity of 33.10 U/g, cellulase activity of 24.41 U/g, xylanase activity of 328.84 U/g were obtained at 8 days incubation with 50%(w/w) soy bean flake, with incubation temperature of $25^{\circ}C$, pH of 6.38, optimal moisture content of 55% and with inoculum size of $3.8{\times}10^6$spore/g. Enzyme activities were enhanced when ImM $CaSO_4$, 2% Malt extract and 2% galactose were added as mineral, nitrogen and carbon enrichment respectively.

• 한국전자통신학회논문지
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• 제9권10호
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• pp.1095-1102
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• 2014

본 논문에서는 실시간 감시 시스템에서 인간의 활동성을 분석하기 위하여 움직임 벡터를 사용하며, 고속연산에 GPU를 활용한다. 먼저 가장 중요한 부분인 전경으로부터 적응적 가우시안 혼합기법, 두드러진 움직임을 위한 가중치 차영상 기법, 움직임 벡터를 이용하여 인간이라고 판단되는 블랍을 검출하고, 추출된 움직임 벡터를 이용하여 사람의 활동성을 분석한다. 본 논문에서는 사람의 행동을 크게 {Active, Inactive}, {Position Moving, Fixed Moving}, {Walking, Running}의 세 가지 메타 클래스로 분류하고 인식하였다. 실험을 위해서 약 300개의 상황을 연출하였으며, 약 86%~98% 의 인식률을 보였다. 또한 $1920{\times}1080$ 크기 영상에서 CPU 기반은 4.2초 정도 걸렸는데, GPU 기반에서는 0.4초 이내로 빨라진 결과를 얻었다.

• KSBB Journal
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• 제23권3호
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• pp.187-192
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• 2008

Lysozyme-producing microorganisms were isolated to obtain bacteria which can efficiently solubilize microbial cells. Cells of normal and chloroform-treated Escherichia coli and Micrococcus Iysodeikticus were used as model substrates to isolate lysozyme-producing microorganisms and investigate the efficiency of cell lysis. The culture supernatant of the isolate New1 (98% similarity of 16S rDNA sequence with Thermomonas haemolytica) showed different lytic characteristics for different substrates. Thermal treatment (autoclave) of substrate cells showed a significant effect on cell solubilization by culture supernatant of the New1. For autoclaved substrate cells, E. coli, M. Iysodeikticus and chloroform-treated E. coli were solubilized by 58.7%, 49.4% and 79.1%, respectively, in the culture supernatant of New1. The lytic activity of New1 was mainly caused by lysozyme produced by the isolate. It was also showed that New1 exhibited high protease activity and a little cellulase activity.

• 대한의생명과학회지
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• 제10권3호
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• pp.179-186
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• 2004

We examined a role of proteasome, the non-lysosomal multicatalytic protease complex,on the differentiation of chick embryonic myoblasts in culture. The peptide hydrolyzing activities of proteasome were found to change; the hydrolyzing activity against N-succinyl-Leu-Leu- Val- Tyr-7 -amido-4-methy1coumarin (SLLVY-AMC) was prominent and increased with myogenic differentiation. Proteasome inhibitors, N-carbobenzoxy-Leu-Leu-norvalinal (MG115) and N-carbobenzoxy-Ile-Glu (O-t-butyl)-Ala-Leucinal (PSI), blocked membrane fusion of myoblasts as well as the SLLVY-AMC hydrolyzing activity. Those inhibitory activities of the agents occurred in parallel, but were reversible and both cell fusion and the peptidase activity were restored when the agents were withdrawn from the culture medium. On the other hand, the agents caused accumulation of the ubiquitinylated proteins in the cytoskeletal proteins. These results suggest that each of the peptide hydrolyzing activities of proteasome is independently regulated during the myogenic differentiation and the chymotrypsin-like activity may play an important role in that process.

• 대한의생명과학회지
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• 제14권1호
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• pp.27-32
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• 2008

To clerify the antioxidant effect of Crataegi Fructus (CF) extract on reactive oxygen species (ROS), The C6 glioma cells were treated with various concentrations of hydrogen peroxide ($H_2O_2$). The $H_2O_2$-induced neurotoxicity was measured by XTT assay for the cell viability. For the protective effect of CF extract on the cytotoxicity induced by $H_2O_2$, cell viability, lactate dehydroganase (LDH) activity, and the inhibitive activity of lipid peroxidation of CF extract were performed. In this study, $H_2O_2$ decreased cell viability dose- and time-dependent manners and increased LDH activity compared with the control. In the protective effect on $H_2O_2$, CF extract increased cell viability and decreased LDH activity on $H_2O_2$-induced cytotoxicity, lipid peroxidation by FTC assay. From these results, It is suggested that $H_2O_2$ was highly toxic on cultured C6 glioma cells, and also, CF extract showed the protective effect on $H_2O_2$-mediated cytotoxicity.

• 동의신경정신과학회지
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• 제3권1호
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• pp.84-90
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• 1992

Solvent and TLC-fractionations of the root of Salvia miltiorrhiza have yielded the results as follows ; Solvent fractions Petr. ether Ether Ethy1 acetate Water Control 100uL 0 0.2 35.1 41.9 43.0 50ul 0.7 3.7 37.2 42.0 TLC-fractionation and the Cytotoxic activity Fractions I II III IV V VI Petr. ehter Control 100uL13.0 7.1 16.8 1.2 30.9 23.2 0.5 48.3 50uL 37.1 26.1 30.0 20.1 45.7 27.2 29.7 Among the solvent fractions the petroleum ehter fraction corresponding to the concentration of 20ug/ml has showed the strongest Cytotoxic activity. (no cell survived) A double dilution of the fraction(10ug/ml) still showed strong activity.(0.2 cells survived) The ether fraction contained strong activity. Of the fraction which have veen obtained by a prcparative silicagel TLC I, II, III & IV were cytotoxic, but V and VI were inactive Howevcr, it is worthwhile to note that no one of these has no strong Cytotoxicity as the pertoleum ether fraction itself. This observation says that the active fractions could be additive or synergic to each other. The most active fraction, IV, was scrached out from the TLC and its UV-spectrum taken. The absorption maxima were 207 and 272 nm, indicating the presence of a flavanone strucuture.

• 생약학회지
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• 제46권3호
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• pp.260-267
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• 2015

Advanced glycation end products (AGEs) have been postulated to play a central role in the development of diabetic complications. A variety of different agents that inhibit AGEs have been under investigation. In this study, 111 herbal medicines from China have been investigated with an in vitro evaluation system using AGEs formation inhibitory activity. Of these, 9 herbal medicines (IC₅₀: <5 μg/ml) were found to have significant AGEs formation inhibitory activity. Particularly, herbal medicines Barleria cristata (leaves), Calotropis gigantea (stems), Ardisia virens (leaves), Dalbergia yunnanensis (leaves) Pittosporum runcatum (leaves), Ardisia japonica (leaves), Rhododendron racemosum (twigs), Oxyria sinensiss (aerial parts), Pyrrosia calvata (whole plants), showed more potent inhibitory activity (approximately 15-40 fold) than the positive control aminoguanidine (IC₅₀: 76.47 μg/ml).