• Applied Science and Convergence Technology
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• v.27 no.4
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• pp.75-77
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• 2018

The electrostatic interaction between emerging quantum-confined nanostructures with plasmonic structures is crucial for future biological applications. Water-soluble green fluorescent copper nanoparticles (Cu-NPs) were fabricated. We demonstrate that L-ascorbic acid is considered as a key to precisely control small Cu-NPs and the capability of the surface ligands, while cetyltrimethylammonium bromide is used as a stabilizing agent controls the particle growth, and stabilizes the nanoparticles. Water-soluble green fluorescent Cu-NPs are tunable through modification of the reaction periods.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.113-118
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• 2022

Multifunctional nanomaterials based on mesoporous silica nanoparticles (MSN) and metal oxide nanocrystals are among the most promising materials for theragnosis because of their ease of modification and high biocompatibility. However, the preparation of multifunctional nanoparticles requires time-consuming multistep processes. Herein, we report a simple one-pot synthesis of multifunctional Mn₃O₄/mesoporous silica core/shell nanoparticles (Mn₃O₄@mSiO₂) involving the temporal separation of core formation and shell growth. This simple procedure greatly reduces the time and effort required to prepare multifunctional nanoparticles. Despite the simplicity of the process, the properties of nanoparticles are not markedly different from those of core/shell nanoparticles synthesized by a previously reported multistep process. The Mn₃O₄@mSiO₂ nanoparticles are biocompatible and have potential for use in optical imaging and magnetic resonance imaging.

• Applied Chemistry for Engineering
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• v.34 no.4
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• pp.365-382
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• 2023

A lithium metal anode with high energy density has the potential to revolutionize the field of energy storage systems (ESS) and electric vehicles (EVs) that utilize rechargeable lithium-based batteries. However, the formation of lithium dendrites during cycling reduces the performance of the battery while posing a significant safety risk. In this review, we discuss various strategies for achieving dendrite-free lithium metal anodes, including electrode surface modification, the use of electrolyte additives, and the implementation of protective layers. We analyze the advantages and limitations of each strategy, and provide a critical evaluation of the current state of the art. We also highlight the challenges and opportunities for further research and development in this field. This review aims to provide a comprehensive overview of the different approaches to achieving dendrite-free lithium metal anodes, and to guide future research toward the development of safer and more efficient lithium metal anodes.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.59.3-59.3
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• 2019

The last two decades have seen an immense growth in our understanding of the physics of the birth and evolution of our Universe. However there are still many unanswered questions, such as: what is the nature of the dark energy, which drives the acceleration of the expansion of the Universe? Is the acceleration driven by a cosmological constant, some dynamical dark energy, or a modification of the gravitational force law on large scales? The next generation of radio observatories will conduct large area radio continuum and HI intensity mapping surveys, and so will make possible new and complimentary tests of these fundamental questions. In this talk I present the design of these next generation of surveys, current forecasts for the effectiveness of these cosmological probes, and results from precursor experiments.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.2
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• pp.77-81
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• 2004

The loss of neurons and synaptic contacts following cerebral ischemia may lead to a synaptic plastic modification, which may contribute to the functional recovery after a brain lesion. Using synapsin I and GAP-43 as markers, we investigated the neuronal cell death and the synaptic plastic modification in the rat hippocampus of a middle cerebral artery occlusion (MCAO) model. Cresyl violet staining revealed that neuronal cell damage occurred after 2 h of MCAO, which progressed during reperfusion for 2 weeks. The immunoreactivity of synapsin I and GAP-43 was increased in the stratum lucidum in the CA3 subfield as well as in the inner and outer molecular layers of dentate gyrus in the hippocampus at reperfusion for 2 weeks. The immunoreactivity of phosphosynapsin was increased in the stratum lucidum in the CA3 subfield during reperfusion for 1 week. Our data suggest that the increase in the synapsin I and GAP-43 immunoreactivity probably mediates either the functional adaptation of the neurons through reactive synaptogenesis from the pre-existing presynaptic nerve terminals or the structural remodeling of their axonal connections in the areas with ischemic loss of target cells. Furthermore, phosphosynapsin may play some role in the synaptic plastic adaptations before or during reactive synaptogenesis after the MCAO.

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.4
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• pp.549-554
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• 2013

With the synthesis of graphene on Cu using CVD, it was tried to show the behavior of graphene growth depending on the size and orientation of Cu grain. It was found out that even under the same temperature and pressure the use of different gases influences on the diffusion rate of Cu. As compared to Ar gas, Cu grain growing bigger under $H_2$ and $CH_4$ was resulted in bigger graphene grain. Corrosion resistance was evaluated by potentiodynamic polarization test in room temperature and found out that the graphene on Cu was more stable in order of 10 than pure Cu due to the chemical stability of graphene. The future work of this research will focus on the synthesis of graphene having no defects including grain boundaries, and its engineering use.

• BMB Reports
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• v.45 no.8
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• pp.470-475
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• 2012

Protein arginine methyltransferase 1 (PRMT1), a type-I arginine methyltransferase, has been implicated in diverse cellular events. We have focused on the role of PRMT1 in gliomagenesis. In this study, we showed that PRMT1 expression was up-regulated in glioma tissues and cell lines compared with normal brain tissues. The knock-down of PRMT1 resulted in an arrest in the G1-S phase of the cell cycle, proliferation inhibition and apoptosis induction in four glioma cell lines (T98G, U87MG, U251, and A172). Moreover, an in vivo study confirmed that the tumor growth in nude mouse xenografts was significantly decreased in the RNAi-PRMT1 group. Additionally, we found that the level of the asymmetric dimethylated modification of H4R3, a substrate of PRMT1, was higher in glioma cells than in normal brain tissues and decreased after PRMT1 knock-down. Our data suggest a potential role for PRMT1 as a novel biomarker of and therapeutic target in gliomas.

• Journal of Korean Public Health Nursing
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• v.27 no.1
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• pp.102-112
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• 2013

Purpose: The purpose of this study was to determine the effects of a weight loss program administered through a smart phone application on body composition and obesity in adolescents. Methods: This study applied a 6-week weight loss program with dietary education, exercise therapy, and behavior modification therapy from 4 June 2012 to 20 July 2012. The collected data were analyzed by descriptive statistics and the Wilcoxon signed rank test using the SPSS WIN 18.0 program. Results: After the 6-week program, the average weight of the subjects was reduced from 75.96kg to 74.41kg (Z=$-3.994^p$, p<.001), while the body mass index (BMI) decreased from 29.23 to 28.60 (Z=$-3.980^p$, p<.001), and the obesity index decreased from 38.45% to 35.59% (Z=$-3.977^p$, p<.001). The percentage of body fat decreased from 32.45 to 31.92 (Z=$-3.947^p$, p<.001), and the rate of skeletal muscle growth increased from 26.06% to 26.58% (Z=$-3.822^p$, p<.001). Conclusion: A weight loss program using a SNS (social network service) application, with dietary education, exercise therapy, and behavior modification therapy can reduce obesity and impact body composition in a short-term. Therefore, the utilization of the SNS application can be used to effectively enhance the management of adolescent obesity.

• Archives of Craniofacial Surgery
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• v.19 no.1
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• pp.3-12
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• 2018

Background: Millard's rotation-advancement repair, which is used by many surgeons, can make a natural philtral column, but most surgeons use a modification of the rotation-advancement flap. The purpose of this article is to introduce a modification utilized by the authors and to provide detailed surgical procedure. Methods: We retrospectively reviewed 82 patients' medical records and presented surgical technique and outcomes. The main features of the authors' strategy are emphasizing horizontal length of the lip, orbicularis oris muscle duplication for improving the definition of the philtral column, overcorrection of domal portion than the non-cleft side in order to compensate for the recurrence during growth. Two judges rated two times the appearance of the patients' nose and lip using Asher-McDade aesthetic index. Intra- and interobserver reliabilities were determined using Cohen's kappa statistics. Results: All patients recovered eventually after surgery; however, two patients have a minor complications (wound infection in one patient, wound disruption due to trauma in the other patient). The improvement of the aesthetic results can be achieved with this modified Millard technique. Total mean scores of the Asher-McDade index was 2.08, fair to good appearance. The intraobserver reliabilities were substantial to almost perfect agreement and the interobserver reliabilities were moderate to almost perfect agreement. Conclusion: We modified Millard method for repair of complete unilateral cleft lip. The surgical outcomes were favorable in long-term follow-up. We hope our technique will serve as a guide for those new to the procedure.

• Journal of Pharmacopuncture
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• v.16 no.4
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• pp.7-13
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• 2013

Objectives: Whether the ultra-highly-diluted remedies used in homeopathy can effectively bring about modulations of gene expressions through acetylation/deacetylation of histones has not been explored. Therefore, in this study, we pointedly checked if the homeopathically-diluted anti-cancer remedy Condurango 30C (ethanolic extract of Gonolobus condurango diluted $10^{-60}$ times) was capable of arresting the cell cycles in cervical cancer cells HeLa by triggering an epigenetic modification through modulation of the activity of the key enzyme histone deacetylase 2 vis-a-vis the succussed alcohol (placebo) control. Methods: We checked the activity of different signal proteins (like $p21^{WAF}$, p53, Akt, STAT3) related to deacetylation, cell growth and differentiation by western blotting and analyzed cell-cycle arrest, if any, by fluorescence activated cell sorting. After viability assays had been performed with Condurango 30C and with a placebo, the activities of histone de-acetylase (HDAC) enzymes 1 and 2 were measured colorimetrically. Results: While Condurango 30C induced cytotoxicity in HeLa cells in vitro and reduced HDAC2 activity quite strikingly, it apparently did not alter the HDAC1 enzyme; the placebo had no or negligible cytotoxicity against HeLa cells and could not alter either the HDAC 1 or 2 activity. Data on $p21^{WAF}$, p53, Akt, and STAT3 activities and a cell-cycle analysis revealed a reduction in DNA synthesis and G1-phase cell-cycle arrest when Condurango 30C was used at a 2% dose. Conclusion: Condurango 30C appeared to trigger key epigenetic events of gene modulation in effectively combating cancer cells, which the placebo was unable to do.