• Archives of Craniofacial Surgery
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• v.14 no.1
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• pp.61-64
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• 2013

Schwannomas are well-differentiated solitary benign tumors that originate from the schwann cells of the nerve sheath. They can readily occur in the head and neck regions, but the schwannoma originating from the infraorbital nerve is extremely rare and usually painless, slow-growing, and without specific symptoms. The author experienced a rare case of infraorbital schwannoma, which was completely removed through the intraoral approach. A 20-year-old woman was admitted to our hospital for a painless, solid and circular mass located on the right infraorbital region. The eyeball movement and visual field were normal. There was no globe displacement or proptosis. Preoperative computed tomography demonstrated $13{\times}10{\times}5mm$-sized soft tissue mass. On March 2011, the mass was removed through an intraoral approach. On histopathological examination, the gross specimen consisted of a smooth, well-encapsulated and light yellowish solid mass, measuring $12{\times}7{\times}5mm$. Microscopically, it presented a typical manifestation of schwannoma with Antoni A area with Verocay body, and Antoni B area on H&E stain. The result of the immunohistochemical staining was positive for the S-100 protein. The patient had hypoesthesia of the nasal septum and vestibule in the postoperative period, and this finding confirmed that the internal nasal branch of infraorbital nerve was the nerve in which the schwannoma originated. Infraorbital schwannomas are very rare and must be included in the differential diagnosis of the orbital masses inferior to the eyeball. In the case of early diagnosis, the small-sized infraorbital schwannomas can be completely removed without any scar through an intraoral approach.

• Journal of Yeungnam Medical Science
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• v.31 no.2
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• pp.139-143
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• 2014

Spontaneous intramuscular hematoma of the abdominal wall is a rare condition characterized by acute abdominal pain. It is often misdiagnosed as a surgical condition. It used to be associated with risk factors such as coughing, pregnancy, and anticoagulant therapy. Most cases of abdominal wall hematomas were rectus sheath hematomas caused by the rupture of either the superior or inferior epigastric artery, but spontaneous internal oblique hematoma was extremely rare. In this report, we present a case of spontaneous internal oblique hematoma in a 69-year-old man with non-dialysis chronic kidney disease who was taking cilostazol. The patient complained of abrupt abdominal pain with a painful palpable lateral abdominal mass while sleeping. The abdominal computed tomography showed an 8 cm-sized mass in the patient's left internal oblique muscle. The administration of cilostazol was immediately stopped, and the intramuscular hematoma of the lateral oblique muscle disappeared with conservative management.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.102-102
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• 2010

수 Tera Watt급의 가속기 및 펄스파워 시스템은 다수의 스위치를 사용하고 있으며, 이와 같은 가속기 및 시스템의 성능은 기체방전 스위치의 성능에 직접적으로 관련되어 있다. 일반적으로 이와 같은 기체방전, 액체방전 고출력 스위치는 다목적으로 많은 연구와 개발에 응용되고 있다. 예를 들어 천둥 펄스전자빔 발생장치는 12개의 Marx gap 및 3개의 100 kV 펄스충전 전기트리거 gap을 가지고 있다. 기체 방전 또는 액체 방전 펄스 충전 갭 스위치의 음극에 펄스 고전압이 인가되면 이로 인하여 음극에서 전자빔이 발생한다. 내부에는 전자빔이 양극과 충돌하는 순간 양극표면에 플라스마가 형성된다. 이와 같은 플라스마 sheath는 축 방향 이극관 안에서 양극충전 에서 음극으로 팽창하면서 전파하며, 또한 거의 동시에 음극표면에도 플라스마가 형성되어 음극에서 양극으로도 팽창하여 전파하게 된다. 이와 같은 펄스충전 고출력 갭 스위치 안에서 발생되는 방전 플라스마의 특성에 관한 갭 breakdown 과정에 대한 특성연구를 한다. 고출력스위치의 특성 조건으로는 방전전압, 방전시간, jitter 등이 있다. 본 연구에서는 최대전압 600 KV, 최대전류 88 KA, 펄스 폭 60 ns의 특성을 가지는 고전압펄스 시스템 '천둥'을 이용하여 방전 챔버에 고전압 펄스를 인가하고 N2와 SF6 혼합기체 종류와 압력에 따른 방전 현상을 연구하였다. 전극은 구리텅스텐 합금재질의 표준전극을 사용하였고, 전극 간격은 20 mm로 고정하였다. 방전 챔버 압력을 100 torr에서 4 기압까지 변화시켜가며 실험을 진행하였고, N2에 대한 SF6의 혼합비율을 0%~100%까지 변화시키며 실험을 진행하였다. 방전 챔버에는 C-dot probe와 B-dot probe를 설치하여 전압과 전류를 측정하였고, C-dot probe 와 B-dot probe는 각각 Northstar사의 10000:1 고전압 probe와 rogowiski coil을 이용하여 시준 하였다. 실험결과 방전전압은 압력이 증가함에 따라 증가하다가 2 기압 이상에서는 완만히 증가하는 경향을 보였고, SF6 혼합비율은 0~10%까지 급격히 증가하고, 그 이상의 혼합비율에서는 완만히 증가하였다. 방전개시시간은 혼합기체 압력에 따라 증가하며 1기압 이상에서는 급격히 증가 하였다. SF6 혼합비율에 따라서는 1 기압 조건까지는 큰 차이가 없었으나 2 기압부터는 급격히 증가하였다. 안정성을 나타내는 jitter는 SF6 100%일 때 가장 컸으나 혼합기체의 변화에 따른 큰 차이는 없었다.

• Progress in Superconductivity and Cryogenics
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• v.23 no.4
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• pp.14-18
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• 2021

The Mg-Powder-Compaction (MPC) process is proposed to fabricate the MgB₂ superconducting wires. Mg powder wall, similar to the Mg metal tube, inside the Nb outer sheath has been made and the stochiometric B powder was inserted into the wall. Even though the very high MgB₂ core density of 2.53 g/cm³ is obtained, the superconducting area fraction of MgB₂ is not high enough for the applications. In this work, an advanced MPC process was adopted by adding Mg powder into B powder. The Mg powder wall in the initial wire was fabricated by controlling the wall thickness while maintaining a constant density, and the mixture of B and Mg powder was filled into the Mg powder wall with the same filling density. It is found that the reduction in the area of the Mg powder wall proceeds similar to the wire, and the Mg powder wall is well maintained at the final wire diameter, which is advantage for the fabrication of long wires. With the advanced MPC process, as the added Mg is increased the densities of MgB₂ core is decreased and the porous structure is formed, it is found that the area fraction of superconducting MgB₂ increase up to the 37.7 % with the improved high critical current density (J_c) and the engineering critical current density (J_e).

• Tuberculosis and Respiratory Diseases
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• v.82 no.3
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• pp.201-210
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• 2019

Background: Radial probe endobronchial ultrasound (R-EBUS) is widely used for diagnosing peripheral pulmonary lesions. However, the utility of R-EBUS-guided transbronchial lung biopsy (TBLB) for diffuse lung lesions (DLLs) remains unknown. We designed this study to evaluate the utility of R-EBUS-guided TBLB in DLLs. Methods: This retrospective study enrolled patients admitted from January 2016 to November 2017 who underwent TBLB for DLLs. The R-EBUS-guided TBLB and blind TBLB groups were compared. DLL was defined as any lung disorder that involved more than one segment of the lung. In both the groups, fluoroscopy and guided sheath were not used during TBLB. Results: A total of 127 patients underwent TBLB for DLLs (67 patients in the R-EBUS-guided TBLB group and 60 in the blind TBLB group). There were no differences in age, sex, and comorbid illnesses between the two groups. Furthermore, there was no difference in the TBLB diagnostic yield of the two groups (p=0.660) although more samples were collected from the R-EBUS-guided TBLB group (p=0.003). Procedure time was significantly longer in the R-EBUS-guided TBLB group than in the blind TBLB group (p<0.001). Thus, incidence of pneumothorax was significantly lower in the R-EBUS-guided TBLB group than in the blind TBLB group (p=0.032). Conclusion: Diagnostic yield in DLLs did not differ between the R-EBUS-guided TBLB and blind TBLB groups. Findings show that R-EBUS-guided TBLB in DLLs may reduce risk of pneumothorax.

• Korean Circulation Journal
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• v.48 no.12
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• pp.1120-1130
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• 2018

Background and Objectives: Feasibility of coronary angiography (CAG) and percutaneous coronary intervention (PCI) via left snuffbox approach is still concerned. We aimed to investigate efficacy and safety of the left snuffbox approach for CAG and PCI. Methods: Left snuffbox approach was tried in 150 patients who planned to perform CAG or PCI for suspected myocardial ischemia between 1 November 2017 and 31 March 2018. Results: Success rate of radial artery (RA) cannulation via snuffbox approach was 88.0% (n=132). Among 132 individuals, 58 (43.9%) acute coronary syndrome (ACS) patients were included. The diameter of snuffbox RA was significantly smaller than conventional RA (2.57 mm vs. 2.72 mm, p<0.001) from quantitative computed angiography of 101 patients. However, CAG via snuffbox approach by 6 French sheath was successfully performed in all 132 patients. In addition, there was significant correlation between the snuffbox and conventional RA diameter (r=0.856, p<0.001). In 42 PCI cases, including 25 patients with acute myocardial infarction (AMI), the success rate of PCI via snuffbox approach was 97.6% (n=41). Intravascular imaging-guided PCI was performed in 8 (19.5%) patients and multi-vessel PCI in 4 (9.8%) cases. Regarding vascular complication, forearm swelling with bruising, not requiring surgery or transfusion, occurred in 2 (4.9%) PCI cases. Conclusions: Left snuffbox approach is suitable for CAG and PCI compared with the conventional radial approach.

• Journal of Microbiology and Biotechnology
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• v.29 no.1
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• pp.66-78
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• 2019

In this study, strain KNU17Pc1 was tested for its antifungal activity against Rhizoctonia solani AG-1(IA), which causes banded leaf and sheath blight (BLSB) of maize. KNU17Pc1 was tested further for its broad-spectrum antifungal activity and in vitro plant growth promoting (PGP) traits. In addition, the in vivo effects of KNU17Pc1 on reduction of BLSB severity and seedling growth promotion of two maize cultivars under greenhouse conditions were investigated. On the basis of multilocus sequence analysis (MLSA), KNU17Pc1 was confirmed as P. chlororaphis subsp. aurantiaca. The study revealed that KNU17Pc1 had strong in vitro antifungal activity and was effective toward all in vitro PGP traits except phosphate solubilization. In this study, for the first time, a strain of P. chlororaphis against Colletotrichum dematium, Colletotrichum gloeosporioides, Fusarium oxysporum f.sp. melonis, Fusarium subglutinans and Stemphylium lycopersici has been reported. Further biochemical studies showed that KNU17Pc1 was able to produce both types of phenazine derivatives, PCA and 2-OH-PCA. In addition, solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis identified 13 volatile organic compounds (VOCs) in the TSB culture of KNU17Pc1, 1-undecene being the most abundant volatile. Moreover, for the first time, Octamethylcyclotetrasiloxan (D4), dimethyl disulfide, 2-methyl-1,3-butadiene and 1-undecene were detected in P. chlororaphis. Furthermore, this study reported for the first time the effectiveness of P. chlororaphis to control BLSB of maize. Hence, further studies are necessary to test the effectiveness of KNU17Pc1 under different environmental conditions so that it can be exploited further for biocontrol and plant growth promotion.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3236-3246
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• 2021

Lessons learned from the Fukushima Daiichi nuclear power plant accident directed that multiple failures should be considered more seriously rather than single failure in the licensing bases and safety cases because attempts to take accident management measures could be unsuccessful under the high radiation environment aggravated by multiple failures, such as complete loss of electric power, uncontrollable loss of coolant inventory, failure of essential safety function recovery. In the case of the complete loss of electric power called station blackout (SBO), if there is no mitigation action for recovering safety functions, the reactor core would be overheated, and severe fuel damage could be anticipated due to the failure of the active heat sink. In such a transient condition at CANDU-6 plants, the seal failure of the primary heat transport (PHT) pumps can facilitate a consequent increase in the fuel sheath temperature and eventually lead to degradation of the fuel integrity. Therefore, it is necessary to specify the regulatory guidelines for multiple failures on a licensing basis so that licensees should prepare the accident management measures to prevent or mitigate accident conditions. In order to explore the efficiency of implementing accident management strategies for CANDU-6 plants, this study proposed a realistic accident analysis approach on the SBO transient with multiple-failure sequences such as seal failure of PHT pumps without operator's recovery actions. In this regard, a comparative study for two PHT pump seal failure modes with and without coolant seal leakage was conducted using a best-estimate code to precisely investigate the behaviors of thermal-hydraulic parameters during transient conditions. Moreover, a sensitivity analysis for different PHT pump seal leakage rates was also carried out to examine the effect of leakage rate on the system responses. This study is expected to provide the technical bases to the accident management strategy for unmitigated transient conditions with multiple failures.

• Journal of Veterinary Science
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• v.19 no.6
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• pp.750-758
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• 2018

Influenza virus infection is a zoonosis that has great socioeconomic effects worldwide. Influenza infection induces respiratory symptoms, while the influenza virus can infect brain and leave central nervous system sequelae. As children are more vulnerable to infection, they are at risk of long-term neurological effects once their brains are infected. We previously demonstrated that functional changes in hippocampal neurons were observed in mice recovered from neonatal influenza infection. In this study, we investigated changes in myelination properties that could affect neural dysfunction. Mice were infected with the influenza virus on postnatal day 5. Tissues were harvested from recovered mice 21-days post-infection. The expression levels for myelin basic protein (MBP) were determined, and immunohistochemical staining and transmission electron microscopy were performed. Real-time polymerase chain reaction and Western blot analyses showed that mRNA and protein expressions increased in the hippocampus and cerebellum of recovered mice. Increased MBP-staining signal was observed in the recovered mouse brain. By calculating the relative thickness of myelin sheath in relation to nerve fiber diameter (G-ratio) from electron photomicrographs, an increased G-ratio was observed in both the hippocampus and cerebellum of recovered mice. Influenza infection in oligodendrocyte-enriched primary brain cell cultures showed that proinflammatory cytokines may induce MBP upregulation. These results suggested that increased MBP expression could be a compensatory change related to hypomyelination, which may underlie neural dysfunction in recovered mice. In summary, the present results demonstrate that influenza infection during the neonatal period affects myelination and further induces functional changes in influenza-recovered mouse brain.

• The Plant Pathology Journal
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• v.37 no.2
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• pp.87-98
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• 2021

To establish an infection, fungal pathogens must recognize diverse signals from host surfaces. The rice blast fungus, Magnaporthe oryzae, is one of the best models studying host-pathogen interactions. This fungus recognizes physical or chemical signals from the host surfaces and initiates the development of an infection structure called appressorium. Here, we found that protein MoAfo1(appressorium formation, MGG_10422) was involved in sensing signal molecules such as cutin monomers and long chain primary alcohols required for appressorium formation. The knockout mutant (ΔMoafo1) formed a few abnormal appressoria on the onion and rice sheath surfaces. However, it produced normal appressoria on the surface of rice leaves. MoAfo1 localized to the membranes of the cytoplasm and vacuole-like organelles in conidia and appressoria. Additionally, the ΔMoafo1 mutant showed defects in appressorium morphology, appressorium penetration, invasive growth, and pathogenicity. These multiple defects might be partially due to failure to respond properly to oxidative stress. These findings broaden our understanding of the fungal mechanisms at play in the recognition of the host surface during rice blast infection.