• Journal of the Korean institute of surface engineering
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• v.55 no.2
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• pp.120-132
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• 2022

In the non-cyanide-based electroless Au plating solution using thiomalic acid as a complexing agent and aminoethanethiol as a reducing agent, analysis of each component constituting the plating solution is essential for the analysis of the reaction mechanism. And component analysis in the plating solution is important for monitoring component changes in the plating process and optimizing the management method. Capillary Electrophoresis (CE) method is rapid, sensitive and quantitative and could be readily applied to analysis of Auⁿ⁺ ion, complexing agent and reducing agent in electroless Au plating solution. In this study, the capillary electrophoresis method was used to analyze each component in the electroless Au plating solution in order to elucidate the complex bonding form and the plating mechanism of the non-cyanide-based electroless Au plating bath. The purpose of this study was to establish data for optimizing the monitoring and management method of plating solution components to improve the uniformity of precipitation and stability. As a result, it was confirmed that the analysis of thiomalic acid as a complexing agent and Auⁿ⁺ ions and the analysis of aminoethanethiol as a reducing agent were possible by capillary electrophoresis. In the newly developed non-cyanide-based electroless Au plating solution, it was confirmed that Auⁿ⁺ ions exist in the form of Au⁺ having a charge of +1, and that thiomalic acid and Au⁺ are combined in a molar ratio of 2 : 1. In addition, it was confirmed that aminoethanethiol can form a complex by combining with Au⁺ ions depending on conditions as well as acting as a reducing agent.

• Journal of the Korea Institute of Building Construction
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• v.22 no.4
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• pp.371-378
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• 2022

The Ryomyong Street project is the only construction project for which the construction cost is known, but its scale cannot be estimated because it is marked in North Korean Won. In this paper, the construction cost per m² of North Korean apartment building construction was calculated based on the construction and assembly amount of the Ryomyong Street project. 160 to 1 was calculated as the ratio of the building construction cost per m² between South and North Korea based on the Ryomyong Street project in Pyongyang and Seoul Housing & Communities Corporation. This ratio can be used to assume the construction size presented in North Korean won as there is no official exchange rate between the two Koreas.

• Nuclear Engineering and Technology
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• v.55 no.8
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• pp.2873-2878
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• 2023

The purpose of this study is to perform radiation monitoring by acquiring gamma images and real-time optical images for ^99mTc vial source using charge couple device (CCD) cameras equipped with the proposed compact gamma camera. The compact gamma camera measures 86×65×78.5 mm³ and weighs 934 g. It is equipped with a metal 3D printed diverging collimator manufactured in a 45 field of view (FOV) to detect the location of the source. The circuit's system uses system-on-chip (SoC) and field-programmable-gate-array (FPGA) to establish a good connection between hardware and software. In detection modules, the photodetector (multi-pixel photon counters) is tiled at 8×8 to expand the activation area and improve sensitivity. The gadolinium aluminium gallium garnet (GAGG) measuring 0.5×0.5×3.5 mm³ was arranged in 38×38 arrays. Intrinsic and extrinsic performance tests such as energy spectrum, uniformity, and system sensitivity for other radioisotopes, and sensitivity evaluation at edges within FOV were conducted. The compact gamma camera can be mounted on unmanned equipment such as drones and robots that require miniaturization and light weight, so a wide range of applications in various fields are possible.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.2
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• pp.35-46
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• 2023

The transplanting period limit considering the rice yield in the Dague region, the inland plains of Gyeongsangbuk-do, was estimated to be July 15^th for early and mid-maturing rice and July 5^th for mid-late maturing rice. However, as the transplanting time was delayed, the characteristics of rice starch changed significantly. In the case of early and mid-maturing rice varieties, the starch granule size increased as the transplanting time was delayed; the opposite tendency was observed for mid-late maturing varieties. In all mature rice types, the late transplanting resulted in a longer pasting time and a higher pasting temperature. In addition, the peak viscosity, breakdown, and gelatinization temperature were significantly lowered, the relative crystallinity degree decreased, and the setback was significantly increased. In the case of Ilpum, a mid-late maturing rice variety, the distribution of amylopectin short chains tended to increase when rice was transplanted on June 30^th.

• Membrane and Water Treatment
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• v.15 no.1
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• pp.1-9
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• 2024

Biological nutrient removal is gaining increasing attention in wastewater treatment plants; however, it is adversely affected by low temperatures. This study examined temperature effects on nutrient removal and morphological stability of the granular and denitrifying phosphorus accumulating organisms (PAO and DPAO, respectively) using sequencing batch reactors (SBRs) at 5, 10, and 20 ℃. Lab-scale SBRs were continuously operated using anaerobic-anoxic and anaerobic-oxic cycles to develop the PAO and DPAO granules for 230 d. Sludge granulation in the two SBRs was observed after approximately 200 d. The average removal efficiency of soluble chemical oxygen demand (SCOD) and PO₄^3--P remained >90% throughout, even when the temperature dropped to 5 ℃. The average removal efficiency of NO₃^--N remained >80% consistently in DPAO SBR. However, nitrification drastically decreased at 10 ℃. Hence, the removal efficiency of NH₄⁺-N was decreased from 99.1% to 54.5% in PAO SBR. Owing to the increased oxygen penetration depth at low temperatures, the influence on nitrification rates was limited. The granule in DPAO and PAO SBR was observed to be unstable and disintegrated at 10 ℃. In conclusion, morphological characteristics showed that changed conversion rates at low temperatures in aerobic granular sludge altered both nutrient removal efficiencies and granule formation.

• Journal of Microbiology and Biotechnology
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• v.33 no.7
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• pp.909-914
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• 2023

While searching for the bacteria which are responsible for degradation of pesticide in soybean field soil, a novel bacterial strain, designated 5-5^T, was isolated. The cells of the strain were Gram-staining-positive, aerobic and non-motile rods. Growth occurred at 10-42℃ (optimum, 30℃), pH 5.5-9.0 (optimum, pH 7.0-7.5), and 0-2% (w/v) NaCl (optimum, 1%). The predominant fatty acids were C_15:0 anteiso, C_17:0 anteiso, and summed feature 8 (C_18:1 ω7c and/or C_18:1 ω6c). The predominant menaquinone was MK-9 (H₂). Diphosphatidylglycerol, glycolipids, phosphatidylinositol, and phosphatidylglycerol were the major polar lipids. Phylogenetic analysis of 16S rRNA gene sequences indicated that strain 5-5^T is a member of the genus Sinomonas and its closest relative is Sinomonas humi MUSC 117^T, sharing a genetic similarity of 98.4%. The draft genome of strain 5-5^T was 4,727,205 bp long with an N50 contig of 4,464,284 bp. Genomic DNA G+C content of strain 5-5^T was68.0 mol%. The average nucleotide identity (ANI) values between strain 5-5^T and its closest strains S. humi MUSC 117^T and S. susongensis A31^T were 87.0, and 84.3 % respectively. In silico DNA-DNA hybridization values between strain 5-5^T and its closest strains S. humi MUSC 117^T and S. susongensis A31^T were 32.5% and 27.9% respectively. Based on the ANI and in silico DNA-DNA hybridization analyses, the 5-5^T strain was considered as novel species belonging to the genus Sinomonas. On the basis of the results from phenotypic, genotypic and chemotaxonomic analyses, strain 5-5^T represents a novel speciesof the genus Sinomonas, for which the name Sinomonas terrae sp. nov. is proposed. The type strain is 5-5^T (=KCTC 49650^T =NBRC 115790^T).

• Archives of Plastic Surgery
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• v.34 no.6
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• pp.685-690
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• 2007

Purpose: Numerous materials, both autologous and nonautologous, have been used for augmentation of sunken areas and each has its own limitations. The ideal material for augmentation should not be absorbed in any manner. This study is designed to assess the survival of $SureDerm^{(R)}$, $Permacol^{(R)}$ graft according to the volume and histologic change. Methods: Twenty four mice, weighing about 50 grams and of 5 weeks of age were used. $SureDerm^{(R)}$ is an acellular dermal matix obtained from human cadeveric skin. $Permacol^{(R)}$ is a porcine derived acellular dermal matrix whose manufacture involves trypsinisation, solvent extraction. Graft pieces standardized to $1{\times}1cm$ size were used in each group. The implanted material were taken 1, 4, 8 and 12 weeks later, respectively. The changes of graft volume during the graft period were measured on initial, 1, 4, 8 and 12 weeks. Results: The initial shape of graft was maintained up to 12 weeks in $Permacol^{(R)}$ graft group and mean survival rate was $80.36{\pm}8.21%$ in $SureDerm^{(R)}$, $89.57{\pm}6.39%$ in $Permacol^{(R)}$(p=0.01). The volume of each graft decreased 29% from initial volume on 12 weeks in $SureDerm^{(R)}$, 18% in $Permacol^{(R)}$. The structure of $Permacol^{(R)}$ remained until 12 week after implantation. Conclusion: Our experimental study suggests that $Permacol^{(R)}$ could be a safe material as an implant for permanent augmentation. However, There are further study remained for antigenicity of these material, and the choice of graft for augmentation should be remained to the clinical situations.

• Korean Journal of Materials Research
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• v.26 no.10
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• pp.561-569
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• 2016

$SrAl_2O_4$: $Eu^{2+}$ and $Dy^{3+}$ phosphorescent phosphors were synthesized using the polymerized complex method. Generally, phosphorescent phosphors synthesized by conventional solid state reaction show a micro-sized particle diameter; thus, this process is restricted to applications such as phosphorescent ink and paint. However, it is possible to synthesize homogeneous multi-component powders with fine particle diameter by wet process such as the polymerized complex method. The characteristics of $SrAl_2O_4$: $Eu^{2+}$ and $Dy^{3+}$ powders prepared by polymerized complex method with one and two step calcination processes were comparatively analyzed. Temperatures of organic material removal and crystallization were observed through TG-DTA analysis. The crystalline phase and crystallite size of the $SrAl_2O_4$: $Eu^{2+}$ and $Dy^{3+}$ phosphorescent phosphors were analyzed by XRD. Microstructures and afterglow characteristics of the $SrAl_2O_4$: $Eu^{2+}$ and $Dy^{3+}$ phosphors were measured by SEM and spectrofluorometry, respectively.

• BMB Reports
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• v.49 no.4
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• pp.208-213
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• 2016

Prolonged ER stress (ERS) can be associated with the induction of apoptotic cell death in various heart diseases. In this study, we searched for microRNAs affecting ERS in the heart using in silico and in vitro methods. We found that miR-185 directly targets the 3′-untranslated region of Na⁺/H⁺ exchanger-1 (NHE-1), a protein involved in ERS. Cardiomyocyte ERS-triggered apoptosis induced by 100 ng/ml tunicamycin (TM) or 1 μM thapsigargin (TG), ERS inducers, was significantly reduced by miR-185 overexpression. Protein expression of pro-apoptotic markers such as CCAAT/enhancer-binding protein homologous protein (CHOP) and cleaved-caspase-3 was also markedly reduced by miR-185 in a dose-dependent manner. Cariporide (20 μM), a pharmacological inhibitor of NHE-1, also attenuated ERS-induced apoptosis in cardiomyocytes and CHOP protein expression, suggesting that NHE-1 plays an important role in ERS-associated apoptosis in cardiomyocytes. Collectively, the present results demonstrate that miR-185 is involved in cardio-protection against ERS-mediated apoptotic cell death.

• Herbal Formula Science
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• v.28 no.1
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• pp.71-80
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• 2020

Obejectives : The purpose of this study was to investigate the effects of Yijin-tang on pacemaker potentials of small intestinal interstitial Cells of Cajal (ICC). Methods : To dissociate the ICC, we used enzymatic digestions from the small intestine in mice. The electrophysiological whole-cell patch-clamp configuration was used to record pacemaker potentials in the cultured ICC and the in vivo effects of Yijin-tang on GI motility were investigated by calculating percent intestinal transit rates (ITR). Results : 1. The ICC generated pacemaker potentials in the murine small intestine. Yijin-tang produced membrane depolarization with concentration-dependent manners in the current clamp mode. 2. Pretreatment with a Ca²⁺ free solution and thapsigargin, a Ca²⁺-ATPase inhibitor in the endoplasmic reticulum, stopped the pacemaker potentials. In the case of Ca²⁺-free solutions and thapsigargin, Yijin-tang did not induce membrane potential depolarizations. 3. U73122, a phospholipase C (PLC) inhibitors, blocked the Yijin-tang-induced membrane potential depolarizations. However, U73343, an inactive PLC inhibitors, did not block. 4. In the presence of protein kinase C (PKC) inhibitors, staurosporine or Rottlerin, Yijin-tang depolarized the pacemaker potentials. However, in the presence of Go6976, Yijin-tang did not depolarize the pacemaker potentials. 5. In mice, intestinal transit rate (ITR) values were significantly and dose-dependently increased by the intragastric administration of Yijin-tang. Conclusions : These results suggest that Yijin-tang can modulate the pacemaker activity of ICC through an internal/external Ca²⁺ and PLC/PKC-dependent pathway in ICC. In addition, Yijin-tang is a good candidate for the development of a prokinetic agent.