• Clinical Endoscopy
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• 제51권6호
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• pp.513-526
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• 2018

White light imaging (WLI) may not reveal early upper gastrointestinal cancers. Linked color imaging (LCI) produces bright images in the distant view and is performed for the same screening indications as WLI. LCI and blue laser imaging (BLI) provide excellent visibility of gastric cancers in high color contrast with respect to the surrounding tissue. The characteristic purple and green color of metaplasias on LCI and BLI, respectively, serve to increase the contrast while visualizing gastric cancers regardless of a history of Helicobacter pylori eradication. LCI facilitates color-based recognition of early gastric cancers of all morphological types, including flat lesions or those in an H. pylori-negative normal background mucosa as well as the diagnosis of inflamed mucosae including erosions. LCI reveals changes in mucosal color before the appearance of morphological changes in various gastric lesions. BLI is superior to LCI in the detection of early esophageal cancers and abnormal findings of microstructure and microvasculature in close-up views of upper gastrointestinal cancers. Excellent images can also be obtained with transnasal endoscopy. Using a combination of these modalities allows one to obtain images useful for establishing a diagnosis. It is important to observe esophageal cancers (brown) using BLI and gastric cancers (orange) surrounded by intestinal metaplasia (purple) and duodenal cancers (orange) by LCI.

• Clinical Endoscopy
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• 제51권6호
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• pp.558-562
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• 2018

Background/Aims: While the occurrence of multiple whitish flat elevated lesions (MWFL) was first reported in 2007, no studies on MWFL have been published to date. The present retrospective observational study aimed to clarify the endoscopic findings and clinicopathological features of MWFL. Methods: Subjects were consecutive patients who underwent upper gastrointestinal endoscopy as part of routine screening between April 2014 and March 2015. The conventional white-light, non-magnifying and magnifying narrow-band images were reviewed. Clinical features were compared between patients with and without MWFL. Results: The conventional endoscopic findings of MWFL include multiple whitish, flat, and slightly elevated lesions of various sizes, mainly located in the gastric body and fundus. Narrow-band imaging enhanced the contrast of MWFL and background mucosa, and magnifying narrow-band imaging depicted a uniformly long, narrow, and elliptical marginal crypt epithelium with an unclear microvascular pattern. Histopathological findings revealed hyperplastic changes of the foveolar epithelium, and parietal cell protrusions and oxyntic gland dilatations were observed in the fundic glands, without any intestinal metaplasia. The rate of acid-reducing drug use was significantly higher in patients with MWFL than in those without (100% [13/13] vs. 53.7% [88/164], p<0.001). Conclusions: The present study indicated a relationship between the presence and endoscopic features of MWFL and history of acid-reducing drug use.

• Clinical Endoscopy
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• 제51권6호
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• pp.570-575
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• 2018

Background/Aims: Capsule endoscopy is a diagnostic method for evaluating the small bowel lumen and can detect undiagnosed lesions. The aim of this study was to evaluate the diagnostic yield and clinical impact of capsule endoscopy in patients with refractory diarrhea-predominant irritable bowel syndrome and functional abdominal pain. Methods: This study involved a retrospective analysis of prospectively collected data, maintained in a database. Patients with refractory diarrhea-predominant irritable bowel syndrome and functional abdominal pain within the period of March 2012 to March 2014 were included. Capsule endoscopy was used to detect small bowel pathologies in both groups. Results: Sixty-five patients (53.8% female) fulfilled the inclusion criteria and had a mean (${\pm}$standard deviation) age of $50.9{\pm}15.9$ years. Clinically significant lesions were detected via capsule endoscopy in 32.5% of the patients in the abdominal pain group and 54.5% of the patients in the diarrhea group. Overall, 48% of patients had small bowel pathologies detected during the capsule endoscopy study. Inflammatory lesions and villous atrophy were the most frequent lesions identified in 16.9% and 15.3% of patients in the abdominal pain and the diarrhea groups, respectively. Conclusions: Routine use of capsule endoscopy in patients with irritable bowel syndrome should not be recommended. However, in patients with refractory conditions, capsule endoscopy may identify abnormalities.

• Clinical Endoscopy
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• 제51권6호
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• pp.576-583
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• 2018

Background/Aims: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) remains the most common EUS-guided tissue acquisition technique. This study aimed to evaluate the performance of a new Franseen tip fine needle biopsy (FNB) device for EUSguided sampling of solid lesions and compare it with the historical FNA technique. Methods: $Acquire^{(R)}$ 22 G FNB needle (Boston Scientific Co., Natick, MA, USA) was used for solid tumor sampling (Study group). Tissue was collected for rapid on-site evaluation, and touch and crush preparations were made. Historical EUS-FNA samples obtained using $Expect^{(R)}$ 22 G FNA needle (Boston Scientific Co.) were used as controls (Control group). All specimens were independently evaluated by two cytopathologists blinded to the formal cytopathological diagnosis. Results: Mean cell block histology scores were significantly higher (p=0.046) in the FNB group (51 samples) despite a significantly lower (p<0.001) mean number of passes compared to the FNA group (50 specimens). The overall diagnostic yields for the FNB vs. FNA groups were 96% vs. 88%. The degree of tumor differentiation was adequately assessed in all cell block qualifying lesions in the FNB group. Two patients developed post-FNB abdominal pain. Conclusions: The new Franseen tip FNB device provides histologically superior and cytologically comparable specimens to those obtained by FNA, but with fewer passes.

• 한국초전도ㆍ저온공학회논문지
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• 제20권4호
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• pp.41-45
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• 2018

We have investigated the effect of $Y_2O_3$ nanoparticles on the pinning properties of $Y_2O_3$-doped $GdBa_2Cu_3O_{7-{\delta}}$ (GdBCO) films. Both undoped and $Y_2O_3$-doped GdBCO films were grown on $CeO_2$-buffered MgO (100) single crystal substrates by pulsed laser deposition (PLD) using KrF (${\lambda}=248nm$) laser. The $Y_2O_3$ doping contents were controlled up to ~ 2.5 area% by varying the internal angles of $Y_2O_3$ sectors put on the top surface of GdBCO target. Compared with the $Gd_2O_3$-doped GdBCO films previously reported by our group [1], the $Y_2O_3$-doped GdBCO films exhibited less severe critical temperature ($T_c$) drop and thus slightly enhanced critical current densities ($J_c$) and pinning force densities ($F_p$) at 65 K for the applied field parallel to the c-axis of the GdBCO matrix (B//c) with increasing the doping content. Below 40 K, the in-field $J_c$ and $F_p$ values of all $Y_2O_3$-doped GdBCO films exhibited higher than those of undoped GdBCO film, suggesting that $Y_2O_3$ inclusions might act as effective pinning centers.

• 한국전기전자재료학회논문지
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• 제32권4호
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• pp.281-286
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• 2019

Raman spectra of a-C:H thin films deposited with an unbalanced magnetron sputtering system showed that the G peak shifted to a higher wavenumber as the target power density increased and $I_D/I_G$ ratio increased from 0.902 to 1.012. Moreover, the transmittance of a-C:H films fabricated at 60 nm tended to decrease with increasing target power density; at 550 nm in the visible light region, the transmittance decreased from 69% to 58%. The rms surface roughness values of the a-C:H thin films decreased with increasing target power density, and varied from 1.11 nm to 0.71 nm. In order to achieve efficient light trapping, the light scattering at the rough interface must be enhanced. Consequently, the surface roughness of the thin film will decrease with the target power density. Further, the refractive index and reflectivity of the a-C:H thin films increased with increasing target power density; however, the Brewster angle decreased with the target power density. Hence, dye-sensitized solar cells using an a-C:H antireflective coating increased the CE, $V_{OC}$, and $J_{SC}$ by approximately 8.6%, 5.5%, and 4.5%, respectively.

• Nuclear Engineering and Technology
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• 제51권5호
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• pp.1428-1435
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• 2019

The total ionizing dose (TID) and non ionizing energy loss (NIEL) effects of 100 MeV phosphorous ($P^{7+}$) and 80 MeV nitrogen ($N^{6+}$) ions on 200 GHz silicon-germanium heterojunction bipolar transistors (SiGe HBTs) were examined in the total dose range from 1 to 100 Mrad(Si). The in-situ I-V characteristics like Gummel characteristics, excess base current (${\Delta}I_B$), net oxide trapped charge ($N_{OX}$), current gain ($h_{FE}$), avalanche multiplication (M-1), neutral base recombination (NBR) and output characteristics ($I_C-V_{CE}$) were analysed before and after irradiation. The significant degradation in device parameters was observed after $100MeV\;P^{7+}$ and $80MeV\;N^{6+}$ ion irradiation. The $100MeV\;P^{7+}$ ions create more damage in the SiGe HBT structure and in turn degrade the electrical characteristics of SiGe HBTs more when compared to $80MeV\;N^{6+}$. The SiGe HBTs irradiated up to 100 Mrad of total dose were annealed from $50^{\circ}C$ to $400^{\circ}C$ in different steps for 30 min duration in order to study the recovery of electrical characteristics. The recovery factors (RFs) are employed to analyse the contribution of room temperature and isochronal annealing in total recovery.

• 근관절건강학회지
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• 제26권2호
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• pp.141-154
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• 2019

Purpose: This study aimed to analyze the effects of exercise on pulmonary function in patients with ankylosing spondylitis (AS). Methods: Randomized controlled trials (RCTs) were identified by searching MEDLINE, EMBASE, CENTRAL, and CINAHL (through Jan 2019). Three reviewers independently retrieved articles, extracted data, and assessed methodological quality using the Cochrane's Risk of Bias for randomized studies. Results: Fourteen studies met the inclusion criteria with a total of 729 participants. CE (SMD 0.58, 95% CI 0.41~0.75, p<.001) and $VO_2peak$ (SMD 0.56, 95% CI 0.24~0.88, p=.001) had a significant effect on the most exercise interventions. As a secondary variable, BASFI (SMD -0.53, 95% CI -0.70~-0.37, p<.001), BASMI (SMD -0.75, 95% CI -0.92~-0.58, p<.001) showed an effect size of more than medium. However, PFT and QoL did not produce a significant results. Conclusion: Pulmonary involvement is common in patients with AS and might have disturbed functionality and exercise modality. Exercise can be an effective intervention to improve pulmonary function in patients with AS. More attention is needed to improve the chest and spinal mobility to maintain the appropriate pulmonary function. It is also necessary to consider how to construct a patient-tailored exercise program to increase performance, accuracy and safety of exercise.

• Journal of Electrochemical Science and Technology
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• 제10권3호
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• pp.335-343
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• 2019

In this study, $Sr_2Ni_{1.8}Mo_{0.2}O_{6-{\delta}}$ (SNM) with a double perovskite structure was investigated as an alternative anode for use in the $CH_4$ fuel in solid oxide fuel cells. SNM demonstrates a double perovskite phase over $600^{\circ}C$ and marginal crystallization at higher temperatures. The Ni nanoparticles were exsolved from the SNM anode during the fabrication process. As the SNM anode demonstrates poor electrochemical and electro-catalytic properties in the $H_2$ and $CH_4$ fuels, it was modified by applying a samarium-doped ceria (SDC) coating on its surface to improve the cell performance. As a result of this SDC modification, the cell performance improved from $39.4mW/cm^2$ to $117.7mW/cm^2$ in $H_2$ and from $15.9mW/cm^2$ to $66.6mW/cm^2$ in $CH_4$ at $850^{\circ}C$. The mixed ionic and electronic conductive property of the SDC provided electrochemical oxidation sites that are beyond the triple boundary phase sites in the SNM anode. In addition, the carbon deposition on the SDC thin layer was minimized due to the SDC's excellent oxygen ion conductivity.

• 한국식품영양학회지
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• 제31권6호
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• pp.949-956
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• 2018

This study investigated chemical components, antioxidant compounds, and activity of brown rice cultivars, to select good cultivar to be used for processing of mixed-rice in the food industry. Proximate compositions, phytic acid, phenolic compounds, and antioxidant activity of brown rice were significantly different among cultivars. Moisture, crude ash, fat, protein, and carbohydrate contents of brown rice were 9.51~12.82, 1.05~1.93, 1.84~6.24, 5.90~9.60 and 71.75~80.34 g/100 g, respectively. Phytic acid content of brown rice cultivars was 7.39~0.87 mg/g. Total polyphenol content of Joeunheukmi and Geonganghongmi cultivars, were 615.25 and $311.14{\mu}g\;GAE/g$, total flavonoid content was 267.75 and $100.67{\mu}g\;CE/g$, respectively. DPPH radical scavenging activity of Geonganghongmi, Joeunheukmi and Hyeugkwang cultivars was 89.17, 87.94 and 43.17%, ABTS radical scavenging activity was 113.57, 113.34, and $93.53{\mu}mol\;TE/g$, and ferric reducing antioxidant potential was 951.67, 1,075.75, and $508.33{\mu}M/g$, respectively. As a result, phenolic compounds and antioxidant activities of pigmented brown rice were high, and it could be used as a functional material.