• Animal cells and systems
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• v.5 no.1
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• pp.31-35
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• 2001

Temperate-resident bats exhibit a circadian cycle of torpor and arousal In summer. The physiological role and selective advantage of torpor as an energy saving mechanism have been received much attention by hibernation biologists. However, despite the significance of the recovering euthermic function, the arousal process and mechanism in these animals have been poorly addressed. In this study, we investigated thermogenic and motor activities of a local bat species Murina leucogaster during arousal by simultaneously examining oxygen consumption rate, body temperature ($T_b$) and pectoral electromyography (EMG). We found that Tb of the torpid bats (12-14$^{\circ}C$) was augmented slowly by nonshivering mechanism during the initial awakening phase. The pectoral shivering, gauged by EMG activity, occurred between 17$^{\circ}C$ and 38$^{\circ}C$. Over this Tb range of shivering, heat was produced at a rate of 0.145 kcal $kg^{-1}\;min^{-1}$ to raise 1$^{\circ}C$ $T_b$ per min. Shivering was most intensive at 30-35$^{\circ}C$ where both EMG amplitude and spike frequency were the highest. Activation of the pectoral myofibers seemed to be controlled in a manner that motor units were recruited from smaller to larger sizes, with greater synchronization, as muscle shivering became intensive with increasing $T_b$.

• Journal of Korean Society on Water Environment
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• v.35 no.6
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• pp.470-480
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• 2019

The Doam lake watershed was designated as a non-point pollution management area in 2007 to improve water quality based on watershed management implementation. There have been studies of non-point source reduction with respect to the watershed management impacting the pollutant transport of the reservoir. However, a little attention has been focused on the impact of water quality improvement by the management of the dam operation or the guidelines on the dam operation. In this study, the impact of in-lake management practices combined with watershed management is analyzed, and the appropriate guidelines on the operation of the dam are suggested. The integrated modeling system by coupling with the watershed model (HSPF) and reservoir water quality model (CE-QUAL-W2) was applied for analyzing the impact of water quality management practices. A scenario implemented with sedimentation basin and suspended matter barrier showed decrease in SS concentration up to 4.6%. The SS concentration increased in the scenarios adjusting withdrawal location from EL.673 m to the upper direction(EL.683 m and EL.688 m). The water quality was comparably high when the scenario implemented all in-lake practices with water intake at EL.673 m. However, there was improvement in water quality when the height of the water intake was moved to EL.688 m during the summer by preventing sediments inflow after the rainfall. Therefore, to manage water quality of the Doam lake, it is essential to control the water quality by modulating the height of water intake through consistent turbidity monitoring during rainfall.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.293.1-293.1
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• 2016

Various materials including conductive, dielectric, and semi-conductive materials, constitute suitable candidates for printed electronics. Metal nanoparticles (e.g. Ag, Cu, Ni, Au) are typically used in conductive ink. However, easily oxidized metals, such as Cu, must be processed at low temperatures and as such, photonic sintering has gained significant attention as a new low-temperature processing method. This method is based on the principle of selective heating of a strongly absorbent film, without light-source-induced damage to the transparent substrate. However, Cu nanoparticles used in inks are susceptible to the growth of a native copper-oxide layer on their surface. Copper-oxide-nanoparticle ink subjected to a reduction mechanism has therefore been introduced in an attempt to achieve long-term stability and reliability. In this work, a flash-light sintering process was used for the reduction of an inkjet-printed Cu(II)O thin film to a Cu film. Using a photographic lighting instrument, the intensity of the light (or intense pulse light) was controlled by the charged power (Ws). The resulting changes in the structure, as well as the optical and electrical properties of the light-irradiated Cu(II)O films, were investigated. A Cu thin film was obtained from Cu(II)O via photo-thermal reduction at 2500 Ws. More importantly, at one shot of 3000 Ws, a low sheet resistance value ($0.2527{\Omega}/sq.$) and a high resistivity (${\sim}5.05-6.32{\times}10^{-8}{\Omega}m$), which was ~3.0-3.8 times that of bulk Cu was achieved for the ~200-250-nm-thick film.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.383-396
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• 2017

The photothermal therapy is a method of cell ablation using the heat converted from the incident light by photothermal transducers. It offers a selective treatment to desired abnormal cells, in particular, tumor tissues. Among various photothermal agents, gold nanoparticles (Au NPs) have received enormous attention due to their unique physicochemical property over last two decades. In this review, we address research strategies and methods to improve treatment efficacy by organizing recent research works. We mainly focus on research works to enhance light-to-heat conversion via optimizing the morphology of Au NPs and related assemblies as well as the strategies to deliver Au NPs efficiently to specific targets. We also introduce convergence research efforts to combine Au NP-mediated photothermal treatment and other functions such as diagnostic capabilities and other therapeutic methods.

• KEPCO Journal on Electric Power and Energy
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• v.3 no.1
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• pp.41-47
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• 2017

After $SF_6$, which is being used in power equipment as an insulating material, is classified as one of the 6 major greenhouse gases, the maintenance and the refinement of used $SF_6$ started to get attention. In regard to this, KEPCO Research Institute (KEPRI) is developing $SF_6$ recovery and refinement technology starting with establishing a comprehensive $SF_6$ analysis system. With the analysis system, qualitative and quantitative analyses of the purity and the impurities of $SF_6$ before and after recovery, and before and after refinement have been carried out. The analysis system is comprised of GC-DID (Gas Chromatograph -Discharge Ionization Detector) for trace impurities analysis, GC-TCD (Thermal Conductivity Detector) for analyses of $SF_6$ purity and major impurities concentration from several hundred ppm up to percent range, GC-MSD (Mass Selective Detector) for analyses of impurities not included in standard gas, FT-IR (Fourier Transform-Infrared) Spectrometer for analysis of HF and $SO_2$, and moisture analyzer for analysis of moisture below 100 ppm. With this analysis system, complete analysis method of $SF_6$ has been established. This analysis system is being used in the maintenance of power equipment and the development of $SF_6$ recovery and refinement technologies. In this paper, the analysis results of four samples - gas and liquid phase $SF_6$ samples from a $SF_6$ refinement system before and after refinement are presented.

• Fashion & Textile Research Journal
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• v.20 no.1
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• pp.34-49
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• 2018

Sustainability in fashion pertains to all stages within the product lifecycle, starting with the procurement of raw materials and ending with the disposal of the product. To clarify, the Lifecycle Management (LCM) views the Triple Bottom Line (TBL) from the perspective of a product's lifecycle. Sustainable products are identified based on their lifecycle, causing public attention to turn towards Product Lifecycle Management (PLM). As of now, PLM is largely known to have a strong impact on New Product Development (NPD). As such, the objective of this research is to study how PLM-based sustainable NPD models, when applied to the fashion industry, can produce a wide understanding of sustainable fashion products from a variety of angles. In order to achieve the research objective, this study did a selective case study on 20 sustainable fashion brands; conducted 1:1 in-depth interviews with 24 fashion experts, including both sustainable and non-sustainable experts; and took part in participant observation of 5 sustainable fashion brands. The results of the study indicate that there are specific conditions that must be met at each stage of production for the development of sustainable products by fashion brands. However, due to the lack of technological skills and the dearth of sustainability experts within the organization, management, monitoring and systematic collection of data is not properly implemented - leading to problems with the quantification of crucial data. This study aims to further forward the debate regarding the development of sustainable fashion products and its future implications.

• Journal of Powder Materials
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• v.27 no.2
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• pp.103-110
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• 2020

Aluminum (Al) - based powders have attracted attention as key materials for 3D printing because of their excellent specific mechanical strength, formability, and durability. Although many studies on the fabrication of 3D-printed Al-based alloys have been reported, the influence of the size of raw powder materials on the bulk samples processed by selective laser melting (SLM) has not been fully investigated. In this study, AlSi10Mg powders of 65 ㎛ in average particle size, prepared by a gas atomizing process, are additively manufactured by using an SLM process. AlSi10Mg powders of 45 ㎛ average size are also fabricated into bulk samples in order to compare their properties. The processing parameters of laser power and scan speed are optimized to achieve densified AlSi10Mg alloys. The Vickers hardness value of the bulk sample prepared from 45 ㎛-sized powders is somewhat higher than that of the 65 ㎛m-sized powder. Such differences in hardness are analyzed because the reduction in melt pool size stems from the rapid melting and solidification of small powders, compared to those of coarse powders, during the SLM process. These results show that the size of the powder should be considered in order to achieve optimization of the SLM process.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.1
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• pp.63-70
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• 2018

Cilostazol is a selective inhibitor of type 3 phosphodiesterase (PDE3) and has been widely used as an antiplatelet agent. Cilostazol mediates this activity through effects on the cyclic adenosine monophosphate (cAMP) signaling cascade. Recently, it has attracted attention as a neuroprotective agent. However, little is known about cilostazol's effect on excitotoxicity induced neuronal cell death. Therefore, this study evaluated the neuroprotective effect of cilostazol treatment against hippocampal neuronal damage in a mouse model of kainic acid (KA)-induced neuronal loss. Cilostazol pretreatment reduced KA-induced seizure scores and hippocampal neuron death. In addition, cilostazol pretreatment increased cAMP response element-binding protein (CREB) phosphorylation and decreased neuroinflammation. These observations suggest that cilostazol may have beneficial therapeutic effects on seizure activity and other neurological diseases associated with excitotoxicity.

• Proceedings of the Korean Vacuum Society Conference
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• 1996.06a
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• pp.40-41
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• 1996

Nitridation technique has been receiving much attention for the formation of a thin nitrided buffer layer on which high quality nitride films can be formedl. Particularly, gallium nitride (GaN) has been considered as a promising material for blue-and ultraviolet-emitting devices. It can also be used for in situ formed and stable passivation layers for selective growth of $GaAs_2$. In this work, formation of a thin nitrided layer is investigated. Nitrogen electron cyclotron resonance(ECR)-plasma is employed for the formation of thin nitrided layer. The plasma source used in this work is a compact ECR plasma gun3 which is specifically designed to enhance control, and to provide in-situ monitoring of plasma parameters during plasma-assisted processing. Microwave power of 100-200 W was used to excite the plasma which was emitted from an orifice of 25 rnm in diameter. The substrate were positioned 15 em away from the orifice of plasma source. Prior to nitridation is performed, the surface of n-type (001)GaAs was exposed to hydrogen plasma for 20 min at $300{\;}^{\circ}C$ in order to eliminate a native oxide formed on GaAs surface. Change from ring to streak in RHEED pattern can be obtained through the irradiation of hydrogen plasma, indicating a clean surface. Nitridation was carried out for 5-40 min at $RT-600{\;}^{\circ}C$ in a ECR plasma-assisted molecular beam epitaxy system. Typical chamber pressure was $7.5{\times}lO^{-4}$ Torr during the nitridations at $N_2$ flow rate of 10 seem.(omitted)mitted)

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3711-3719
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• 2016

Drawbacks of conventional cancer treatments, with lack of specificity and cytotoxicity using current approaches, underlies the necessity for development of a novel approach, gene-directed cancer therapy. This has provided novel technological opportunities in vitro and in vivo. This review focuses on a member of an apoptosis inhibitor family, survivin, as a valuable target. Not only the gene but also its promoter are applicable in this context. This article is based on a literature survey, with especial attention to RNA interference as well as tumor-specific promoter action. The search engine and databases utilized were Science direct, PubMed, MEDLINE and Google. In addition to cell-cycle modulation, apoptosis inhibition, interaction in cell-signaling pathways, cancer-selective expression, survivin also may be considered as specific target through its promoter as a novel treatment for cancer. Our purpose in writing this article was to create awareness in researchers, emphasizing relation of survivin gene expression to potential cancer treatment. The principal result and major conclusion of this manuscript are that survivin structure, biological functions and applications of RNA interference systems as well as tumor-specific promoter activity are of major interest for cancer gene therapy.