• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1500-1506
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• 2011

Tyrosinase is a widespread enzyme with great promising capabilities. The Lineweaver-Burk plots of the catecholase reactions showed that the kinetics of mushroom tyrosinase (MT), activated by $Co^{2+}$ and $Zn^{2+}$ at different pHs (6, 7, 8 and 9) obeyed the non-essential activation mode. The binding of metal ions to the enzyme increases the maximum velocity of the enzyme due to an increase in the enzyme catalytic constant ($k_{cat}$). From the kinetic analysis, dissociation constants of the activator from the enzyme-metal ion complex ($K_a$) were obtained as $5{\times}10^4M^{-1}$ and $8.33{\times}10^3M^{-1}$ for $Co^{2+}$ and $Zn^{2+}$ at pH 9 and 6 respectively. The structural analysis of MT through circular dichroism (CD) and intensive fluorescence spectra revealed that the conformational stability of the enzyme in these pHs reaches its maximum value in the presence of each of the two metal ions.

• Biomolecules & Therapeutics
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• v.18 no.3
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• pp.308-315
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• 2010

Essential oil-excluded Artemisia princeps Pamp var Ssajuarissuk (AP) was fermented with Lactobacillus brevis K-1, which was isolated from cabbage Kimchi, and the anti-inflammatory effects of AP and fermented AP (FAP) on lipopolysaccharide (LPS)-induced inflammatory response in peritoneal macrophages were investigated. AP and FAP inhibited LPS-induced TNF-$\alpha$, IL-$1{\beta}$, COX-2, iNOS and COX-2 expression, as well as NF-${\kappa}B$ activation. AP and FAP also reduced ear thickness, inflammatory cytokine (TNF-$\alpha$, IL-$1{\beta}$ and IL-6) expression and NF-${\kappa}B$ activation with 12-O-tetradecanoylphorbol-13-acetate (TPA) induced dermatitis in mice. Furthermore, AP and FAP also reduced exudate volume, cell number, protein amount, inflammatory cytokines (TNF-$\alpha$, IL-$1{\beta}$ and IL-6) expression and NF-${\kappa}B$ activation in carrageenan-induced air pouch inflammation in mice. The inhibitory effects of FAP were more potent than those of non-fermented AP. Based on these findings, we propose that FAP can improve inflammatory diseases, such as dermatitis, by inhibiting the NF-${\kappa}B$ pathway.

• Analytical Science and Technology
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• v.12 no.4
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• pp.346-353
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• 1999

For the non-destructive multi-elemental analysis of environmental and biological materials, instrumental neutron activation analysis (INAA) was applied for the determination of toxic and trace elements in a set of three Algae samples provided by the International Atomic Energy Agency (IAEA). The analytical quality control was evaluated by comparing the analytical results of two standard reference materials of the National Institute of Standards and Technology (NIST); Oyster Tissue (SRM 1566a) and Citrus Leaves (SRM 1572). According to given analytical procedure, the concentration of 15-25 elements including spiked elements such as As, Cd, Cr and Hg in Algae samples were determined. To identify and validate these results, a data intercomparison program using more than 35 analytical methods in 150 laboratories was carried out and the estimated statistical data are summarized. Result of INAA is favorable, therefore, it is illustrated that can be applied for routine analysis of essential and toxic elements in algae samples as well as analytical quality assurance.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.4
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• pp.889-903
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• 2018

Cloud computing has been activated globally due to the demands of the 4th industrial revolution and the efficient use of IT resources, and domestic usage is also increasing due to legislation and related laws. However, domestic financial companies are subject to various regulations due to the importance of their information and the ripple effects of accidents such as outflows. Only non-critical information processing systems that handle non-critical information are allowed to use cloud computing. Financial companies are required to set specific criteria and judgment to distinguish them. In this paper, we propose a method to enable the financial company cloud computing to be more active by specifying the ambiguous non - essential information processing system designation standard and making it easier to designate.

• Nuclear Engineering and Technology
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• v.55 no.7
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• pp.2650-2655
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• 2023

In the process of growth and development, plants not only absorb essential nutritional elements, but also absorb radioactive and non-essential elements from the environment, and their distribution varies in different parts of the plant. In this study, neutron activation analysis and gamma spectrometry were performed on stems, roots, and leaves of vegetables. The results indicate that the accumulation of radionuclides and multi-elements depends on the plant type and plant parts. Activity concentrations of ²²⁶Ra and ²³²Th in plants were accumulated in the following order: Roots > Stems > Leaves. The highest concentrations of ⁴⁰K and ²¹⁰Pb were observed in the stems and leaves of plants, respectively. Essential nutrient requirements of plants are in the following order: K > Ca > Mg > Fe > Zn > Mn. Among the nonessential metals, the concentration of Na in the vegetable sample was much greater than those of the other elements. The K/Na ratio in the plant depends on the type of plant and the translocation within the plant.

• Journal of Embryo Transfer
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• v.27 no.2
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• pp.121-126
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• 2012

The objective of this study was to examine the effect of in vitro culture media on embryonic development of in vitro-matured (IVM) oocytes after parthenogenetic activation (PA) in pigs. Immature pig oocytes were matured in TCM-199 supplemented with porcine follicular fluid, cysteine, pyruvate, EGF, insulin, and hormones for the first 22 h and then further cultured in hormone-free medium for an additional 22~26 h. IVM oocytes were activated by electric pulses and cultured in porcine zygote medium-3 (PZM-3) and North Carolina State University-23 supplemented with essential and non-essential amino acids (NCSU-23aa). These media were further modified by supplementing 2.77 mM myo-inositol, 0.34 mM trisodium citrate, and $10{\mu}M$ ${\beta}$-mercaptoethanol (designated as mPZM-3 and mNCSU-23aa, respectively). Culture of PA embryos in mPZM-3 significantly increased development to the blastocyst stage than culture in NCSU-23aa (36.2% vs. 24.8%, p<0.05). Modified PZM-3 showed a significantly higher blastocyst formation than NCSU-23aa in both groups of embryos that were activated at 44 h and 48 h of IVM (51.0% vs. 35.5% and 49.0% vs. 34.2% in oocytes activated at 44 h and 48 h of IVM, respectively). Irrespective of the follicle diameter where oocytes were collected, embryonic development to the blastocyst stage was increased (p<0.05) by the culture in mPZM-3 compared to culture in NCSU-23aa (25.9% vs. 34.2% and 32.9% vs. 44.8% in embryos derived from small and medium size follicles, respectively). Our results demonstrated that culture media had significant effect on preimplantation development PA embryos and that mPZM-3 was superior to mNCSU-23 in supporting development to the blastocyst stage in pigs. This beneficial effect of mPZM-3 on embryonic development was not impaired by other factors such as time of oocyte activation and origin of immature oocytes (small and medium size follicles).

• Korean Journal of Materials Research
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• v.30 no.5
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• pp.267-271
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• 2020

Cerium oxide (ceria, CeO₂) is one of the most wide-spread oxide supporting materials for the precious metal nanoparticle class of heterogeneous catalysts. Because ceria can store and release oxygen ions, it is an essential catalytic component for various oxidation reactions such as CO oxidation (2CO + O₂ 2CO₂). Moreover, reduced ceria is known to be reactive for water activation, which is a critical step for activation of water-gas shift reaction (CO + H₂O → H₂ + CO₂). Here, we apply van der Waals-corrected density functional theory (DFT) calculations combined with U correction to study the mechanism of water chemisorption on CeO₂(111) surfaces. A stoichiometric CeO₂(111) and a defected CeO₂(111) surface showed different water adsorption chemistry, suggesting that defected CeO₂ surfaces with oxygen vacancies are responsible for water binding and activation. An appropriate level of water-ceria chemisorption energy is deduced by vdW-corrected non-local correlation coupled with the optB86b exchange functional, whereas the conventional PBE functional describes weaker water-ceria interactions, which are insufficient to stabilize (chemisorb) water on the ceria surfaces.

• The Journal of Information Systems
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• v.26 no.2
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• pp.85-104
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• 2017

Purpose The purpose of this study is to improve the efficiency of the activities of loosely connected network organization through the platform(Ba) of knowledge sharing. Loosely connected network organizations have been tried to promote new work and complement the scarce resources through collaborations. NPO(Non-Profit Organization) is essential to establish cooperation networks in order to achieve the public interest on the basis of scarce resources. This study interpreted the Ba on the 'Change-On' program and analyzed the social networks of regional organizations through the activation of the Ba. The 'Change-On' program is conducted for several years to promote the efficiency of the NPO network by Daum Generation Foundation. Design/methodology/approach This study made a design to organize the Ba concept of Nonaka & Konno and presented a case of the Ba activated based on the NPO network of regional order. According to the social network analysis of regional cooperation within the network of participating organizations was extended, it was found that the principal plays a significant role as a central hub made. Findings According to the empirical analysis, this study illustrated that various types of network were formed among NPOs based on the 'Change-On'. Furthermore, the networks surrounding NPOs are extended to the other people connected to them. This means that the network of NPOs had been diversified via the facilitation of the Ba. This study throws new highlights on the new role for the Ba as a network promoter in addition to the partner as a technology-provider in the NPO ecosystem. Moreover, the network analysis between before-and-after can be used for the evaluation of the effectiveness of the various Ba programs.

• International journal of advanced smart convergence
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• v.6 no.1
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• pp.32-38
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• 2017

In Korea, the act for promoting use of the public data has been enforced since 2013. The Key Government 3.0 Strategy was established for providing the public data as an obligation of public authorities for users to use them free of charge. The aim of open public data and using them targeted by the government is creation of a solution for vitalizing the economy by using the public data. However, the reason for low usability and tangible outcomes despite unlimited provision of open government data is as follows. That is, it is essential to address the issue of difficult software technology required to access public data for using the data. However, with the open API method currently provided, the development procedure is not easy even for IT students or specialized software developers. Therefore, strategies for each step ideal for the level of developers are required to vitalize applications based on the public data and developed by ordinary users. Two strategic methods can be used for facilitating the use of public data and applications developed by ordinary users suggested in this paper on the basis of the public data portal organized by the Ministry of the Interior and provided to all ordinary users. That is, they are applications developed in the web browser environment and those developed in the PC environment. They allow ordinary users to develop and distribute applications based on the public data to contribute to enforcing the policy for facilitating the use of public data of the government just with basic training and basic knowledge from the training without using program coding knowledge of open API which requires the knowledge of development professionals.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.1
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• pp.65-71
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• 2013

The transient receptor potential melastatin type 7 (TRPM7) channel is a widely expressed non-selective cation channel with fusion to the C-terminal alpha kinase domain and regarded as a key regulator of whole body $Mg^{2+}$ homeostasis in mammals. However, the roles of TRPM7 during osteoclastogenesis in RAW264.7 cells and bone marrow-derived monocyte/macrophage precursor cells (BMMs) are not clear. In the present study, we investigate the roles of TRPM7 in osteoclastogenesis using methods of small interfering RNA (siRNA), RT-PCR, patch-clamp, and calcium imaging. RANKL (receptor activator of NF-${\kappa}B$ ligand) stimulation did not affect the TRPM7 expression and TRPM7-mediated current was activated in HEK293, RAW264.7, and BMM cells by the regulation of $Mg^{2+}$. Knock-down of TRPM7 by siTRPM7 reduced intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) increases by 0 mM $[Mg^{2+}]_e$ in HEK293 cells and inhibited the generation of RANKL-induced $Ca^{2+}$ oscillations in RAW264.7 cells. Finally, knock-down of TRPM7 suppressed RANKL-mediated osteoclastogenesis such as activation and translocation of NFATc1, formation of multinucleated cells, and the bone resorptive activity, sequentially. These results suggest that TRPM7 plays an essential role in the RANKL-induced $[Ca^{2+}]_i$ oscillations that triggers the late stages of osteoclastogenesis.