• Molecules and Cells
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• v.19 no.1
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• pp.54-59
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• 2005

Deoxyribonuclease I (DNase I) is a divalent cation dependent endonuclease and thought to be a significant barrier to effective gene delivery. The only known DNase I-specific inhibitor is monomeric actin which acts by forming a 1:1 complex with DNase I. Its use, however, is restricted because of tendency to polymerize under certain conditions. We screened two random phage peptide libraries of complexity $10^8$ and $10^9$ for DNase I binders as candidates for DNase I inhibitors. A number of DNase I-binding peptide sequences were identified. When these peptides were expressed as fusion proteins with Escherichia coli maltose binding protein, they inhibited the actin-DNase I interaction ($IC_{50}=0.1-0.7{\mu}M$) and DNA degradation by DNase I ($IC_{50}=0.8-8{\mu}M$). Plasmid protection activity in the presence of DNase I was also observed with the fusion proteins. These peptides have the potential to be a useful adjuvant for gene therapy using naked DNA.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.519-523
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• 2017

We investigated the applications of functional materials through the examination of a variety of physiological activities of Ipomoea aquatica extract. I. aquatica extract showed low cytotoxicity against murine melanoma B16F10 cells. At concentrations that exerted little or no cytotoxicity to the cells, I. aquatica extract showed high DPPH radical scavenging activity ($ID_{50}$, $7.84{\mu}g/mL$), inhibited tyrosinase activity ($ID_{50}$, $106.56{\mu}g/mL$), and decreased melanin content ($ID_{50}$, $41.75{\mu}g/mL$). The treatment of B16F10 cells with I. aquatica extract suppressed the protein expression of tyrosinase in a dose-dependent manner. These findings suggested that I. aquatica extract inhibited melanin synthesis in murine melanoma B16F10 cells through the suppression of intracellular tyrosinase expression, as well as the simultaneous direct inhibition of tyrosinase activity. Additionally, I. aquatica extract promoted the expression of involucrin, which is related to skin barrier protection. These results indicate that I. aquatica extract may be an appropriate material for the improvement of skin barrier function.

• Microbiology and Biotechnology Letters
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• v.31 no.1
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• pp.51-56
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• 2003

The angiotensin I converting enzyme (ACE) has an important role in the maintenance of blood pressure. The ACE inhibitory activities of foods have recently been studied. We tried to isolate ACE inhibitory peptides from the Flavourzyme (FZ), Pescalase (PE), and Thermolysine (TH) protease digests of corn gluten, which was restricted to the use the source of food for digestion problem. The FZ, PE, TH/PE protease hydrolyzed corn gluten and the inhibitory activities of the hydrolyzates for ACE were measured. Major fractions were isolated from the digests using ODS chromatography after treating with ethanol in step gradient. The ACE inhibitors were further purified by Bio-Gel P-2 column and reverse phase HPLC. Five inhibitory peptides were isolated. Their amino acids were sequenced as LPF ($IC_{50}$ = 40$\mu$M), GPP ($IC_{50}$ = 17.6$\mu$M), PNPY ($IC_{50}$ = 30.7$\mu$M), SPPPFYL ($IC_{50}$ = 63 $\mu$M), and SQPP ($IC_{50}$ = 17.2$\mu$M).

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.31-33
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• 1999

In this paper, a operating characteristics of the 50 kW grid-connected Photovoltaic(PV) Power system which is by means of initial PV datum analyzing is reported. The development of a 50 kW class photovoltaic power generation system including a DC/AC inverter is suggested to investigate the system performance for grid connection. The results of the demonstration test of a 50 kW class grid-connected PV system show that the system utilization rate is 15.6% and the inverter efficiency is 94% at 80% load.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.180-183
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• 1987

Stu I, type II restriction endonuclease, has been purified to homogeneity from Streptomyces tubercidicus (ATCC 25502), and its catalytic properties have been studied. For the purification of Stu I endonuclease free of nonspecific nucleases, DEAE-Sephadex (A-50), QAE-Sephadex (A-50) and Heparin-agarose column chromatography have been performed after ammonium sulfate fractionation of the crude extract. The enzyme was further purified by gel filtration using Sephadex G-100 column to obtain homogeneous form of protein. The single polypeptide species of Stu I endonuclease has a subunit molecular weight of 34,000 $\pm$ 1,000 daltons as judged by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Stu I endonuclease requires $Mg^{2+}$ ion for its activity and is maximally active at neutral pH (7.0-8.0) in the absence of NaCl.

• Journal of Digital Convergence
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• v.17 no.1
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• pp.287-293
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• 2019

The purpose of this study is to research on usability of Seoul Bike focusing on seoul citizens over-50s. Before the test, I researched Seoul Universal Design Guideline's background, purpose, principle and range through literature review. Then I did two tests based on re-establishment of the existing principle to fit the public service. First, I have noticed that using the service through an application was difficult for seoul citizens over-50s even if they have NEEDS for using Seoul Bike according to the survey. Next, I drew the result from User Task Evaluation Analysis. Due to the low app usability(the main point of the service) and accessibility and usability status was rate low, but the overall service process was comfortable and convenience. I expect this study will be a good resouce for public service design.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.5
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• pp.465-475
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• 2020

I-D-F curves were induced by Box-Cox transformation using rainfall data from five major cities in Korea: Seoul, Busan, Daegu, Daejeon, and Gwangju, as well as from Sancheong (South Gyeongsang province) and Yeongcheon (North Gyeongsang province) stations. The practicality of the Box-Cox transformation is more scalable than the traditional method of frequency analysis in terms of applicability because it is available even if the analysis data are insufficient to perform general frequency analysis and do not produce an appropriate probability density function. For the case in which rainfall data for the entire period (10-1440 minutes) and short-term period (20, 30, 40, 50 minutes) at the foregoing 7 stations are omitted, there was a relative error of -23.0 % to 14.7 % at a duration of 10 to 60 minutes below the 100-year frequency. Accordingly, rainfall analysis requires inducing I-D-F curves, including for the short term (20, 30, 40, 50 minutes), and if rainfall data are omitted for the short term (20, 30, 40, 50 minutes), it is necessary to increase the existing margin rate depending on the point in order to ensure the safe design of small-scale hydraulic structures.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.84-85
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• 2003

조개류의 먹이생물인 미세조류를 대체할 수 있는 효모를 개발하기 위하여 빵효모 (Saccharomyces cerevisiae), Candida utilis, Klyveromyces fragilis 3종류의 효모를 대상으로 그 먹이효율을 실험하였다. 이들 3종류의 효모를 세포벽을 75, 50, 25% 제거한 것과 세포벽을 제거하지 않은 효모로 구분하여 Artemia를 대상으로 먹이효율을 조사한 후 가장 좋은 먹이효율을 보인 C. utilis를 조개류의 대표적 먹이생물인 Isoch교sis galbana 와 함께 진주담치 유생을 대상으로 먹이효율을 조사하였다. Artemia 실험결과 빵효모보다 C. utilis, K. fragilis가 높은 생존율과 성장을 보였으며 세포벽을 제거한 것이 제거하지 않은 것보다 유의적으로 높은 생존율을 보였다. Artemia의 생존율은 75%와 50% 세포벽을 제거한 것이 25%에 비해 유의적으로 높은 생존율을 보였다. 성장은 유의적이지는 않지만 전체적으로 세포벽을 많이 제거할수록 성장과 생존율은 높은 경향이었다. 이와같이 Artemia의 경우는 세포벽을 제거한 C. utilis가 더 좋은 먹이효율을 보인 것은 Artemia는 효모의 세포벽을 소화시키지 못하기 때문으로 판단 할 수 있다. 진주담치 유생의 먹이로 C. utilis를 공급한 경우 성장에 있어서 세포벽을 제거한 효모를 50% 대체한 실험구의 먹이효율이 가장 좋았으며 세포벽을 벗기지 않은 효모의 경우 I. galbana에 비해 낮은 결과를 보였다. 진주담치 유생에 있어서도 세포벽을 제거한 C. utilis를 공급한 것은 대조구인 I. galbana와 생존율에 있어 유의성이 없었다. 그리고 25% 세포벽을 제거한 것을 공급한 실험구는 유의적으로 낮은 생존율을 보였다. 각장 성장의 경우 75% 세포벽을 제거한 것은 대조구인 I. galbana와 유의성이 없었다. 세포벽을 제거한 C. utilis와 I. galbana를 1:1로 혼합하여 공급한 실험의 경우 생존율에 있어서는 세포벽을 50%, 75% 제거한 C. utilis를 50% 첨가한 실험구는 대조구인 I. galbana 100%를 공급한 것과 유의적인 차이가 없었다. 그러나 성장의 경우는 I. galbana 에 세모벽을 75% 제거한 C. utilis를 1:1로 혼합한 실험구에서 각장 179.3 $\mu\textrm{m}$, 각고 150.3 $\mu\textrm{m}$로 가장 높았고 대조구인 I. galbana 100%와는 유의적인 차이를 보였다.

• Bulletin of the Korean Chemical Society
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• v.22 no.1
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• pp.30-36
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• 2001

The crystal structures of fully dehydrated $Pd^{2+}$ - and $TI^{+}$ -exchanged zeolite X, $Pd_{18}TI_{56}Si_{100}Al_{92}O_{384}(Pd_{18}TI_{50-}X$, a = $24.935(4)\AA$ and $Pd_{21}TI_{50}Si_{100}Al_{92}O_{384}(Pd_{21}TI_{50-}X$ a = $24.914(4)\AA)$, have been determined by single-crystal X-ray diffraction methods in the cubic space group Fd3 at $21(1)^{\circ}C.$ The crystals were prepared using an exchange solution that had a $Pd(NH_3)_4Cl_2\;:TINO_3$ mole ratio of 50 : 1 and 200 : 1, respectively, with a total concentration of 0.05M for 4 days. After dehydration at $360^{\circ}C$ and 2 ${\times}$$10^{-6}$ Torr in flowing oxygen for 2 days, the crystals were evacuated at $21(1)^{\circ}C$ for 2 hours. They were refined to the final error indices $R_1$ = 0.045 and $R_2$ = 0.038 with 344 reflections for $Pd_{18}Tl_{56-}X$, and $R_1$ = 0.043 and $R_2$ = 0.045 with 280 reflections for $Pd_{21}Tl_{50-}X$; I > $3\sigma(I).$ In the structure of dehydrated $Pd_{18}Tl_{56-}X$, eighteen $Pd^{2+}$ ions and fourteen $TI^{+}$ ions are located at site I'. About twenty-seven $TI^{+}$ ions occupy site II recessed $1.74\AA$ into a supercage from the plane of three oxygens. The remaining fifteen $TI^{+}$ ions are distributed over two non-equivalent III' sites, with occupancies of 11 and 4, respectively. In the structure of $Pd_{21}Tl_{50-}X$, twenty $Pd^{2+}$ and ten $TI^{+}$ ions occupy site I', and one $Pd^{2+}$ ion is at site I. About twenty-three $TI^{+}$ ions occupy site II, and the remaining seventeen $TI^{+}$ ions are distributed over two different III' sites. $Pd^{2+}$ ions show a limit of exchange (ca. 39% and 46%), though their concentration of exchange was much higher than that of $TI^{+}$ ions. $Pd^{2+}$ ions tend to occupy site I', where they fit the double six-ring plane as nearly ideal trigonal planar. $TI^{+}$ ions fill the remaining I' sites, then occupy site II and two different III' sites. The two crystal structures show that approximately two and one-half I' sites per sodalite cage may be occupied by $Pd^{2+}$ ions. The remaining I' sites are occupied by $TI^{+}$ ions with Tl-O bond distance that is shorter than the sum of their ionic radii. The electrostatic repulsion between two large $TI^{+}$ ions and between $TI^{+}$ and $Pd^{2+}$ ions in the same $\beta-cage$ pushes each other to the charged six-ring planes. It causes the Tl-O bond to have some covalent character. However, $TI^{+}$ ions at site II form ionic bonds with three oxygens because the super-cage has the available space to obtain the reliable ionic bonds.

• Bulletin of the Korean Mathematical Society
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• v.50 no.6
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• pp.1855-1861
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• 2013

Let R be a commutative Noetherian ring, I an ideal of R, M and N two R-modules. We characterize the least integer i such that $H^i_I(M,N)$ is not weakly Artinian by using the notion of weakly filter regular sequences. Also, a local-global principle for minimax generalized local cohomology modules is shown and the result generalizes the corresponding result for local cohomology modules.