• Journal of Korea Entertainment Industry Association
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• v.15 no.3
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• pp.153-170
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• 2021

This study was attempted to derive strategic implications for activating professional sports by conducting in-depth interviews with professional sports officials such as players, teams, federations, agencies, etc., by searching for factors that cause match fixing and deriving preventive strategies based on them. Eight people with more than 3 years of experience working in professional sports were selected using the snowball sampling technique. Data were collected and analyzed by applying a semi-structured in-depth interview method for them. As a result of the analysis, five core categories (the learning effect from the cartel for entering university, the culture learned in a camp training, the manifestation of the latent learning effect, the negative effect of the human network, the personal disposition) were derived as factors causing match-fixing. As for the strategy to prevent match fixing, first, improving the college entrance examination system oriented on individual capability, second, improving the education system for student athlete, third, establishing a prevention system, fourth, continuing education, fifth, and activating the agent system as the core categories. Implications for the derived research results and future research directions were discussed.

• Journal of Veterinary Clinics
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• v.39 no.5
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• pp.207-216
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• 2022

Canine babesiosis has been scarcely investigated in the Republic of Korea (ROK). Although it is known that Babesia gibsoni is its primary causative agent, its clinical presentation has not been completely clarified in the ROK. Consequently, the aim of this study was to evaluate the clinical appearance of this parasitic infection based on the anamnesis of the patient and compare of hematological and biochemical test results. Four hundred whole blood samples from patients with a presumptive diagnosis of tick-borne disease were analyzed by polymerase chain reaction (PCR) to amplify the Babesia spp. 18S rRNA gene and by a rapid diagnostic test kit (VetAll Laboratories^®) to detect B. gibsoni seroreactive animals. Thirty-six (9.0%) dogs were PCR-positive but only 24 (6.0%) were seropositive. The investigation revealed that all the courses of the disease are present in the ROK, with the acute course being predominant. The acute course tends to consist of inappetence, lethargy, pyrexia, gastrointestinal symptoms, and occasionally hematuria. It also occurs with common hematological abnormalities, such as thrombocytopenia and anemia, and to a lesser extent biochemical abnormalities, such as hyperbilirubinemia, hypoalbuminemia, and elevated liver enzymes. This research shows that B. gibsoni is an endemic hemoparasite capable of producing a variety of clinical manifestations in dogs. For its accurate diagnosis, a descriptive history of the clinical signs, hematology, and biochemical profile of the patient, along with a well-performing PCR assay, are essential. These findings will help in planning pragmatic preventive strategies against this potent threat in the ROK.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.4
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• pp.41-45
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• 2021

In this study, in order to secure the high reliability of the memristor, we adopted a patterned lithium filament seed layer as the main agent for resistive switching (RS) characteristic on the 30 nm thick ZrO₂ thin film at the device manufacturing stage. Lithium filament seed layer with a thickness of 5 nm and an area of 5 ㎛ × 5 ㎛ were formed on the ZrO₂ thin film, and various electrode areas were applied to investigate the effect of capacitance on filament type memristive behavior in the parallel memristive circuit of memristor and capacitor. The RS characteristics were measured in the samples before and after 250℃ post-annealing for lithium metal diffusion. In the case of conductive filaments formed by thermal diffusion (post-annealed sample), it was not available to control the filament by applying voltage, and the other hand, the as-deposited sample showed the reversible RS characteristics by the formation and rupture of filaments. Finally, via the comparison of the RS characteristics according to the electrode area, it was confirmed that capacitance is an important factor for the formation and rupture of filaments.

• The Journal of Engineering Geology
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• v.31 no.1
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• pp.67-81
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• 2021

Grouting is used for reinforcement and waterproofing of soft ground to increase its bearing capacity, reduce the impacts of rising or lowering groundwater levels, and reduce subsidence due to vibration and general causes. This study investigated the enhancement of grout strength and hardening time by the addition of reinforcing fibers, and the development of non-cement grouting materials from blast furnace slag. An experiment was performed to measure the increase in grout strength resulting from the addition of 0.5% increments of aramid and carbon reinforcing fibers. The results show that the uniaxial compressive strength of grout increases with increasing content of reinforcing fiber. Comparison of three admixtures of finely powdered blast furnace slag and 10%, 20%, and 30% calcium hydroxide stimulating agent showed that the uniaxial compressive strength of the mixture increases with increasing content of alkaline stimulant; however, the strength was lower than for 100% pure cement. The reaction of calcium hydroxide with blast furnace slag powder, which increases the strength of the grout, is more effective if injected as a solution rather than a powder.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.4
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• pp.182-189
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• 2021

Porous ceramics were manufactured using the foaming method for the development of inorganic insulating materials. Silica fume and SiO₂ were used as main raw materials, and bentonite was used as a rapid setting agent for uniform structure formation of porous ceramics. The porous ceramics were sintered at 1200℃, and porosity, density, compressive strength, microstructure and thermal conductivity were analyzed. As the content of silica fume to SiO₂ of the porous ceramics increased 70 to 90 %, the specific gravity increased from 0.63 to 0.69, and the compressive strength increased from 9.41 Mpa to 12.86 Mpa. But, the porosity showed a tendency to decrease from 72.07 % to 70.82 %, contrary to the specific gravity. As a result of measuring the thermal conductivity, the porous ceramic with a silica fume content of 70 % showed a thermal conductivity of 0.75 to 0.72 W/m·K at 25 to 800℃, respectively, and, another that a silica fume content of 90 % showed a 0.66~0.86 W/m·K. So the lower the silica f ume content, the lower the thermal conductivity, which was conf irmed to be consistent with porosity result. As a result of microstructure analysis using SEM (Scanning Electron Microscope), pores in the range of tens to hundreds ㎛ were observed inside and outside the porous ceramic, and it was confirmed that the pore distribution was relatively uniform.

• The Korea Journal of Herbology
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• v.32 no.4
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• pp.53-60
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• 2017

Objectives : Collagen decrease of Skin appears through various path ways. One of causes may be the Advanced glycation endproducts (AGEs) that combine formation of glucose and protein. The aim of this study was to explore the prevent wrinkle formation of Paeoniae radix (PR) and heated Paeoniae radix (HPR) via AGEs path way. Methods : AGEs formation inhibitory activities of PR and HPR measured using bovine serum albumin, glucose, and fructose. To evaluate the protective effects of PR and HPR in diabetic rats induced with streptozotocin (STZ) and methyl glyoxal (MGO), SD rat were distributed into four groups. Normal rats (Nor), AGEs-induced rats (Con), AGEs-induced rats treated with 100 mg/kg PR(PR), AGEs-induced rats treated with 100 mg/kg HPR (HPR). To induce AGEs, streptozotocin (50 mg/kg) was administered intraperitoneally and after 3 days administrated 100mM methyl glyoxal for 3 weeks. Results : The oral administration of HPR inhibited AGEs in skin tissues compared with PR. The increased reactive oxygen species (ROS) levels in the serum were diminished by HPR treatment. The analyses of kidney and skin tissues proteins indicated that HPR treatment effectively reduced AGEs related protein levels as compared to that by PR treatment. Also, HPR decreased anti-oxidant related protein levels in skin tissues such as catalase, glutathione peroxidase. Moreover, it inhibited the reduction of COL1A2 by decreasing MMP-1. Conclusion : Based on these results, it was suggested that PR and HPR could have Improving effects on wrinkle formation. These evidences provide useful information for the development wrinkle formation treated agent.

• Journal of Marine Life Science
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• v.7 no.1
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• pp.15-20
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• 2022

Glioblastoma is one of the highly aggressive central nervous system tumors and it is difficult to treat owing its anatomical location. Peptides are novel class of drugs which has the potential to cross the blood brain barrier and exerts its anti-tumor activity. Here, we discovered a novel peptide from abalone (Haliotis discus hannai) next generation sequencing (NGS) data and tested its anticancer effect on glioblastoma cell line SNU-489. The anticancer activity was measured using a cytotoxicity assay in a time and dose-dependent manner. A concentration and time dependent increase in the cytotoxicity was seen in cells treated with the novel peptide. The highest cytotoxicity rate of about 67% was observed in SNU-489 cells treated with 200 µM peptide for 48 hrs. However, the cytotoxic effect was not or less observed in a normal skin cell line HaCaT at similar concentration, thus, evident of peptide's cell specific anticancer activity. In addition, the gene expression level of necroptosis-related genes was analyzed by qRT-PCR to elucidate the anticancer mechanism of the novel peptide. RIPK3 expression was significantly increased by 9.6-fold in 200 µM of novel peptide treatment group, and MLKL expression level was significantly elevated by 2-fold in 100 µM treated group compared to the control group. Therefore, this study confirmed that the novel abalone-derived peptide has anticancer potency, and it causes cancer cell death through the necroptosis mechanism. Collectively, these results suggest that the novel peptide could be candidate anticancer agent for the treatment of glioblastoma in the future.

• Journal of Adhesion and Interface
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• v.23 no.2
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• pp.44-52
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• 2022

Epoxy resin has the disadvantage of being easily destroyed by instantaneous impact due to its high crosslinking density despite its high glass transition temperature (T_g) and excellent properties. To compensate for this, in this study, polyol was synthesized by ring opening polymerization of propylene glycol (PPG) diamine, Jeffamine D 2000 and propylene carbonate, and urethane modified epoxy was synthesized using this. The properties of the synthesized urethane modified epoxy were confirmed by FT-IR, H-NMR. To confirm the degree of improvement in impact resistance as an adhesive, a urethane modified epoxy adhesive was prepared by mixing a digylcidyl ether bisphenol A (DGEBA) with curing agent and curing accelerator. Properties test of urethane modified epoxy were shear strength, tensile strength and impact strength. As a result, excellent results were obtained in all test when the ratio of DGEBA : urethane modified epoxy was 8:2.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.6
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• pp.270-275
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• 2021

ZnO was synthesized according to the transformation behavior and crystallization conditions of Zn-intermediate obtained by zinc sulfate as a precursor and NaOH, Na₂CO₃ as a alkali agents. For ZnO crystallization, Zn₄(OH)₆SO₄·H₂O and Zn₅(OH)₆(CO₃)₂·H₂O as a Zn-intermediate were calcined at 400℃ and 800℃ for 1 h, respectively, based on decomposition temperature from TGA. Zn₄(OH)₆SO₄·H₂O was confirmed to have mixed Zn₄(OH)₆SO₄·H₂O and ZnO at 400℃, and was completely thermally decomposed at 800℃ to form ZnO phase. The prepared Zn₅(OH)₆(CO₃)₂·H₂O as a Zn-intermediate by the reaction with Na₂CO₃ was transformed to a complete ZnO crystallization over 400℃. Nano-sized ZnO can be synthesized at a relatively lower calcination temperature through the reaction with Na₂CO₃.

• Journal of Veterinary Science
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• v.21 no.5
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• pp.64.1-64.14
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• 2020

Background: Canine distemper virus (CDV) infection results in high morbidity and mortality in dogs. There has been no report about Isolation of Korean CDV since 1980 in Korea. Objectives: To investigate the biological properties and the genetic characterization of Korean CDV. Methods: Vero cells expressing dog signaling lymphocyte activation molecule (dSLAM) gene named as Vero/dSLAM were used to isolate CDV using 17 samples. Diagnostic methods such as cytopathic effects, immunofluorescence assay, peroxidase linked assay, electron microscopy, rapid immunodiagnostic assay, and reverse transcription polymerase chain reaction were used to confirm the Korean CDV isolate as a CDV. The genetic analysis was performed through cloning and sequencing of hemagglutinin gene of CDV isolate. Results: A virus propagated in Vero/dSLAM cell was confirmed as CDV (CD1901 strain) based on the above methods. The CD1901 strain showed the highest viral titer (10^5.5 50% tissue culture infectious dose [TCID₅₀]/mL) in the Vero/dSLAM cells at 4 days post inoculation, but did not form a fork on chorioallantoic membrane of 7-day-old egg. Ribavirin, a nucleotide analogue anti-viral agent, inhibits moderately the Korean CDV propagation in the Vero/dSLAM cells. The nucleotide and amino acid sequences of the H gene of CD1901 strain were compared with those of other CDV strains. The CD1901 strain belonged to Asia 1 group and had the highest similarity (99.9%) with the BA134 strain, which was isolated in China in 2008. Conclusions: We constructed successfully Vero/dSLAM and isolated one Korean CDV isolate (CD1901 strain) from a naturally infected dog. The CD1901 strain belonged to Asia 1 genotype.