• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.5
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• pp.635-643
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• 2003

Parametric study for the analysis of performance characteristics of a planar -type solid oxide fuel cell(SOFC) using computational flow analysis is conducted. A planar -type SOFC, which is composed by two gas channels (fuel and ai.) and one set of anode-electrolyte-cathode assembly, is modeled as a two -dimensional isothermal case. Results of computational analysis of flow field including distributions of mass fractions in gas channels are used to the performance analysis of the fuel cell. Flow analysis makes it possible to consider current density distributions along the length of the cell in the process of performance analysis of the SOFC. As results of parametric study, it is found that the mole fraction of fuel at the inlet of fuel channel, operating pressure and temperature are closely related to the performance characteristics of SOFC.

• Journal of the Korean Ceramic Society
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• v.42 no.12 s.283
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• pp.846-853
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• 2005

For the performance prediction of a planar-type solid oxide fuel cell, the computational analysis of transport phenomena with a simplified treatment of heat generation by the electrochemical reaction is conducted. From the result of the computational analysis, it is shown that the electrochemical reaction is closely related to the transport phenomena inside a solid oxide fuel cell. Transport phenomena including heat and mass transfer influences on the distribution of local current density and, as a result, on the performance characteristics of the fuel cell. Computational analysis is also extended to the parametric study to investigate the performance behavior of the fuel cell with different amount of supplied fuel flow rates. It is also demonstrated that the mathematical formulation and computational procedures proposed in this study can be applied to prove the importance of the specific TPB area in the manufacturing process of electrodes in solid oxide fuel cells.

• Korean Journal of Materials Research
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• v.30 no.2
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• pp.81-86
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• 2020

MoO₃ metal oxide nanostructure was formed by hydrothermal synthesis, and a perovskite solar cell with an MoO₃ hole transfer layer was fabricated and evaluated. The characteristics of the MoO₃ thin film were analyzed according to the change of hydrothermal synthesis temperature in the range of 100 ℃ to 200 ℃ and mass ratio of AMT : nitric acid of 1 : 3 ~ 15 wt%. The influence on the photoelectric conversion efficiency of the solar cell was evaluated. Nanorod-shaped MoO₃ thin films were formed in the temperature range of 150 ℃ to 200 ℃, and the chemical bonding and crystal structure of the thin films were analyzed. As the amount of nitric acid added increased, the thickness of the thin film decreased. As the thickness of the hole transfer layer decreased, the photoelectric conversion efficiency of the perovskite solar cell improved. The maximum photoelectric conversion efficiency of the perovskite solar cell having an MoO₃ thin film was 4.69 % when the conditions of hydrothermal synthesis were 150 ℃ and mass ratio of AMT : nitric acid of 1 : 12 wt%.

• Microbiology and Biotechnology Letters
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• v.21 no.1
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• pp.59-65
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• 1993

We isolated Actinomycetes strain GMT 1155 and purified the active compound, MT 1155, on the morphological reversion of ts/NRK cell from the isolate. MT 1155 was identified as toyocamycin having antifungal and antitumor activities from physico-chemical properties and UV, IR, $^1H$-NMR, $^13C$-NMR and mass spectrum. MT 1155 showed the morphologically reversional activity on ts/NRK cell and the cytotoxicity on CTLL cell at the final concentrations of 1.7 JlM and 0.2 11M, respectively and its $IC_{50}$ value on protein kinase A enzyme was 2.3 $\mu$M. Also it had strong antifungal activity against several pathogenic fungi but not antibacterial activity. And it did not inhibit both protein kinase C activity and the bleb-formation of K562 cell induced by phorbol esters.

• The Korean Journal of Cytopathology
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• v.4 no.1
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• pp.35-40
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• 1993

We describe a case of fine needle aspiration cytology of metastatic nasopharyngeal carcinoma in the lymph node of the neck presenting a predominantly spindle cell pattern. A 36 year-old male patient complained of dysesthesia on the right face and a palpable neck mass. Fine needle aspiration was done on the neck mass. Tumor cells were present in syncytial groups or singly with mainly spindle shaped nuclei, vesicular chromatin, thin and regular nuclear membrane, occasional prominent nucleoli and a few fool of cellular cohesiveness. The cytoplasm was scant and pale with ill-defined borders. Mature lymphocytes were present in the background of aspirates and within the tumor cell clusters. Histologically, the tumor of nasopharynx showed several areas of spindle cell pattern. Because the tumor cells showed a predominantly spindle shape with vesicular nuclear chromatin, the differential diagnosis of spindle cell sarcoma or granuloma of epithelioid clils were considered, but the characteristic morphology of the nuclei with vesicular chromatin and prominent nucleoli, and cellular cohesiveness were important in making the diagnosis of nasopharyngeal carcinoma. The possibility of metastatic carcinoma should always be considered in fine needle aspiration cytology of the lymph node in the neck because the incidence of metastatic carcinoma, particularly of the nasopharyngeal carcinoma in the lymph nodes of the neck is relatively high.

• Archives of Plastic Surgery
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• v.37 no.6
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• pp.819-822
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• 2010

Purpose: Basal cell nevus syndrome (BCNS), also known as Gorlin syndrome, is a rare autosomal dominant disorder. It is characterized by complex neoplastic syndrome with multisystemic manifestations, involving six major features. This article presents a rare genetic disorder and usage of the author's methods for odontogenic keratocyst, developed in the maxillary sinus. Methods: A 67-year-old man was presented with large calcified maxillary mass and multisystemic manifestations and findings that matched with basal cell nevus syndrome. The calcified maxillary mass was removed via the versatile maxillary window and maxillary bone segment was repositioned. Results: Histopathologic findings revealed that maxillary and mandibular lesions were odontogenic keratocysts and the skin lesions were basal cell carcinoma. Conclusion: Basal cell nevus syndrome is a rare genetic disease that requires surveillance and care for basal cell carcinoma and multisystemic problems. The author's method was satisfactory for maxillary odontogenic keratocyst in the aspect of the approach and reconstruction.

• Journal of the Korean Society of Radiology
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• v.83 no.6
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• pp.1412-1417
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• 2022

Renomedullary interstitial cell tumors are often incidentally identified either upon autopsy or kidney resection for other reasons. However, rare renomedullary interstitial cell tumor cases resulting in a clinical symptomatic mass have been reported. We present a case of renomedullary interstitial cell tumor that was manifested as an incidentally detected renal mass and mimicked renal cell carcinoma on the imaging features.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.1-9
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• 1996

The possibility of using waste brine and cabbage waste from kimchi industry as raw materials for the production of yeast cell mass was investigated. Among four strains of osmotolerant yeast, Candida guilliermondii ATCC 6260 showed the best growth in the waste brine containing about 1.0g/L of reducing sugar and 7% to 12% of NaCl. The growth of C. guilliermondii in waste brine was affected slightly between the temperature range of $25^{\circ}C$ to $35^{\circ}C$ and the initial pH of 3 to 6. The NaCl concentration up to 9% was not inhibitory to the growth of C. guilliermondii and the addition of 10mM of ammonium salts or 5mM of potassium phosphate had no effect on the growth. The growth of yeast reduced BOD of the waste brine by 85% within 24hours. When C. guilliermondii was cultured in waste brine added with cabbage juice extracted from waste cabbage, the cell mass was increased significantly.

• Journal of Microbiology and Biotechnology
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• v.8 no.3
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• pp.203-207
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• 1998

Fed-batch fermentations with different feeding media were carried out in order to increase the productivity of invertase expression using a recombinant Saccharomyces cerevisiae containing plasmid pRB58. Two batch cultures showed the expression of the SUC2 gene at a low concentration of glucose, suggesting that glucose concentration could be used as a control variable in a fed-batch operation mode. In the fed-batch culture by feeding the basal medium, cell mass and specific invertase activity did not increase much as compared with the simple batch culture. A series of fed-batch cultures revealed that the sucrose-supplemented medium increased cell mass whereas the enriched medium did specific invertase activity. To capitalize on the synergism of the sucrose-supplemented medium and the enriched medium, the sucrose-supplemented enriched medium was used as a feeding medium. The fed-batch culture using this medium resulted in a 2.4-fold increase in cell mass and a 1.9-fold enhancement in specific invertase activity compared with those of the batch culture. The increase in cell mass and specific invertase activity led to a marked increase in total invertase activity, 250U/ml, which was 6.3 times higher than that of the batch culture.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.26 no.3
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• pp.244-250
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• 2022

Backgrounds/Aims: Early recovery after surgery has become a popular trend. The aim of this study was to evaluate effect of nutritional intervention using Encover, an oral nutritional supplement, in patients undergoing hepato-biliary-pancreatic surgery. Methods: This single center, prospective case-control study was conducted in Gangnam Severance Hospital from September 2018 to April 2019. Through randomization, patients were divided into an experimental group (30 patients) and a control group (30 patients). At postoperative seven days, the experimental group was instructed to take two packs of Encover (JW Pharmaceutical, Seoul, Korea) daily for seven days. Body cell mass index was measured at seven days after surgery and 14 days after discharge and Patient-Generated Subjective Global Assessment (PG-SGA) was performed at 14 days after discharge. Results: Body cell mass index during outpatient follow-up was significantly decreased compared to that at discharge in both groups. However, the amount of body cell mass index showed no significant difference between postoperative seven days and outpatient follow-up in either group. During outpatient follow-up, the experimental group had a higher mean value of PG-SGA score than the control group (11.32 ± 3.46 vs. 9.48 ± 3.97; p = 0.037). Conclusions: Short-term Encover doses after surgery may not produce significant results in weight gain or other body cell mass index. Encover did not significantly affect other dietary conditions based on PG-SGA.