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Journal of Energy Chemistry 2022年第7期31卷 583-592,I0014页

作者： Seung-Young Choi kyeong sik jin Polymer&Materials Chemistry Department of ChemistryLund UniversitySE-22100Sweden Center for Hydrogen·Fuel Cell Research Korea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Pohang Accelerator Laboratory Pohang University of Science and Technology(POSTECH)PohangKyungbuk 37673Republic of Korea

Prolonged hydrothermal treatment for sulfonated poly(ether ether ketone) membranes induces mechanical degradation and developing hydrophilic-hydrophobic phase separation, simultaneously. The enhanced phase separation provides incremental proton conductivity to the membranes, whereas mechanical degradation drastically reduces device stability. On this basis, we describe here the effects of two different ex situ aging processes on sulfonated poly(ether ether ketone) membranes: hydrationdehydration cycling and prolonged hydrothermal treatment. Both aged membranes exhibited enhanced phase separation under the hydrated conditions, as characterized by small angle X-ray ***, when the aged membranes were dried again, the nanostructure of the membranes aged via the hydration-dehydration cycling was recoverable, whereas that of the membranes aged via prolonged hydrothermal treatment was irreversible. Furthermore, the two differently aged membranes showed clear differences in thermal, mechanical, and electrochemical properties. Finally, we implemented both aged membranes in fuel cell application. The sample aged via hydration-dehydration cycling maintained its improved cell performance, whereas the sample aged via hydrothermal treatment showed drastically reduced cell performance after durability test for 50 h.

关键词： Sulfonated poly(ether ether ketone) Humidity cycle test Ex situ aging Proton exchange membrane Fuel cell

Is it now possible to transition from laparoscopic liver resection to robotic liver resection?

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Hepatobiliary Surgery and Nutrition 2024年第3期13卷 557-559页

作者： kyeong sik Kim Dae Won Jun Department of General Surgery College of MedicineHanyang UniversitySeoulKorea Department of Internal Medicine College of MedicineHanyang UniversitySeoulKorea Hanyang Institute of Bioscience and Biotechnology Hanyang UniversitySeoulKorea

Minimally invasive surgery(MIS)has significantly progressed and emerged as the preferred approach for various gastrointestinal procedures,including gastrectomy,cholecystectomy,and various colorectal surgeries(1).However,the widespread acceptance of robotic surgery in liver resection has encountered obstacles,attributed to factors such as the lack of appropriate surgical instruments,the intricate learning curve,and safety ***,the utilization of MIS in liver resection is linked to decreased blood loss,reduced post-operative pain,shorter hospital stays,and lower morbidity rates compared to both open and laparoscopic liver resection procedures(2).

关键词： Laparoscopic liver resection robotic liver resection minimally invasive surgery(MIS)

Characterization of smooth muscle, enteric nerve, interstitial cells of Cajal, and fibroblast-like cells in the gastric musculature of patients with diabetes mellitus

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World Journal of Gastroenterology 2016年第46期22卷 10131-10139页

作者： Kyung sik Park Kwang Bum Cho Il Seon Hwang Jae Hyung Park Byung Ik Jang kyeong Ok Kim Sung Woo Jeon Eun Soo Kim Chang sik Park Joong Goo Kwon Department of Internal Medicine Keimyung University School of Medicine Department of Pathology Keimyung University School of Medicine Department of Physiology Keimyung University School of Medicine Department of Internal Medicine Youngnam University College of Medicine Department of Internal Medicine Kyungpook National University School of Medicine Department of Advanced Materials Convergence Korea Institute of Ceramic Engineering and Technology Department of Internal Medicine Catholic University of Daegu School of Medicine

AIM To investigate histologic abnormalities in the gastric smooth muscle of patients with diabetes mellitus(DM).METHODS Full-thickness gastric specimens were obtained from patients undergoing surgery for gastric cancer. H&E stain and Masson's Trichrome stain were performed to assess the degree of fibrosis. Immunohistochemical staining using various antibodies was also performed [antibodies against protein gene product 9.5(PGP9.5), neuronal nitric oxide synthase(n NOS), vasoactive intestinal peptide(VIP), neurokinin-1(NK1) receptor, c-Kit, and platelet-derived growth factor receptor-alpha,(PDGFRα)]. Immunofluorescent staining and evaluation with confocal microscopy were also *** Twenty-six controls and 35 diabetic patients(21 shortduration patients and 14 long-duration patients) were included. There were no significant differences in basic demographics between the two groups except in mean body mass index(BMI)(higher in the DM group). Proportions of moderate-to-severe intercellular fibrosis in the muscle layer were significantly higher in the DM group than in the control group(P < 0.01). On immunohistochemical staining, c-Kit- and PDGFRα-positive immunoreactivity were significantly decreased in the DM group compared with the control group(P < 0.05). There were no statistically significant differences in PGP9.5, n NOS, VIP, and neurokinin 1 expression. On immunofluorescent staining, cellularity of interstitial cells of Cajal(ICC) was observed to decrease with increasing duration of *** Our study suggests that increased intercellular fibrosis, loss of ICC, and loss of fibroblast-like cells are found in the smooth muscle of DM patients. These abnormalities may contribute to changes in gastric motor activity in patients with DM.

关键词： Diabetes mellitus Interstitial cells of Cajal Fibroblast-like cell Gastroparesis Enteric nerve system

Effects of various sintering methods on microstructure and mechanical properties of CP-Ti powder consolidations

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Transactions of Nonferrous Metals Society of China 2014年第S1期24卷 59-67页

作者： Je-ha SHON Jong-moon PARK kyeong-sik CHO Jae-keun HONG Nho-kwang PARK Myung-hoon OH Department of Advanced Materials Engineering Kumoh National Institute of Technology Gumi Gyeongbuk 730-701 Korea Advanced Technology Team Pohang Institute of Metal Industry Advancement Pohang Gyeongbuk 790-834 Korea Titanium Department Korea Institute of Materials Science (KIMS) Changwon Gyeongnam 642-831 Korea

Effects of various sintering methods such as spark plasma sintering(SPS), hot pressing(HP) and electric resistance sintering(ERS) on the microstructure and mechanical properties of commercial pure titanium(CP-Ti) powder consolidations with particle size of <147 μm, <74 μm and <43 μm were studied. The smaller particle powders are densified to proceed at a higher rate. Dense titanium with relative density up to 99% is found to take place at 850 °C under 30 MPa of SPS and HP condition. However, in case of ERS, CP-Ti powders were densified almost at 950 °C under 30 MPa. The microstructure of sintered titanium is composed of equiaxed grains at 850-950 °C. The yield strength of sintered body composed of <43 μm powder is 858 MPa by using SPS at 850 °C under 30 MPa. When there is a higher content of small particle, the higher yield strength value is obtained both by using SPS and HP. However, when ERS is introduced, the highest yield strength is 441 MPa at 950 °C under 30 MPa, which shows much lower values than those by SPS and HP methods. ERS method takes much less sintering time compared with SPS and HP. Nevertheless, higher sintering temperature results in lower strength and elongation because of brittle fracture.

关键词： CP-Ti powders sintering method spark plasma sintering hot pressing electrical resistance sintering

Significant risk and associated factors of active tuberculosis infection in Korean patients with inflammatory bowel disease using anti-TNF agents

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World Journal of Gastroenterology 2015年第11期21卷 3308-3316页

作者： Eun Soo Kim Geun Am Song Kwang Bum Cho Kyung sik Park kyeong Ok Kim Byung Ik Jang Eun Young Kim Seong Woo Jeon Hyun Seok Lee Chang Heon Yang Yong Kook Lee Dong Wook Lee Sung Kook Kim Tae Oh Kim Jonghun Lee Hyung Wook Kim Sam Ryong Jee Seun Ja Park Hyun jin Kim Division of Gastroenterology Department of Internal MedicineKeimyung University School of Medicine Division of Gastroenterology Department of Internal MedicinePusan National University School of Medicine Division of Gastroenterology Department of Internal MedicineYeungnam University College of Medicine Division of Gastroenterology Department of Internal MedicineCatholic University of Daegu School of Medicine Division of Gastroenterology Department of Internal MedicineKyungpook National University School of Medicine Division of Gastroenterology Department of Internal MedicineDongguk University School of Medicine Division of Gastroenterology Department of Internal MedicineInje University College of Medicine Division of Gastroenterology Department of Internal MedicineDong-A University Medical Center Division of Gastroenterology Department of Internal MedicineKosin University College of Medicine Division of Gastroenterology Department of Internal MedicineGyeongsang National University School of Medicine

AIM:To evaluate the incidence and risk factors of Korean tuberculosis(TB) infection in patients with inflammatory bowel disease(IBD) undergoing anti-TNF ***:The data of IBD patients treated with anti-TNFs in 13 tertiary referral hospitals located in the southeastern region of Korea were collected *** failed to show response or were intolerant to conventional treatments,including steroids or *** measures for latent TB infection(LTBI)and the incidence and risk factors ofactive TB infection after treatment with anti-TNFs were ***:Overall,376 IBD patients treated with antiTNF agents were recruited(male 255,mean age of anti-TNF therapy 32.5±13.0 years);277 had Crohn’s disease,99 had ulcerative colitis,294 used infliximab,and 82 used *** anti-TNF treatment,screening tests for LTBI including an interferon gamma release assay or a tuberculin skin test were performed in 82.2%of *** patients(8%)had *** cases of active TB infection including one TB-related mortality occurred during 801 personyears(PY)follow-up(1997.4 cases per 100000 PY)after anti-TNF ***(OR=5.76,95%CI:1.57-21.20,P=0.008)and WBC count<5000 mm3(OR=4.5,95%CI:1.51-13.44,P=0.007)during follow-up were identified as independently associated risk ***:Anti-TNFs significantly increase the risk of TB infection in Korean patients with *** considerable burden of TB and marked immunosuppression might be attributed to this risk.

关键词： Tuberculosis Anti-TNF Korea Inflammatory bowel dis

Chemical characterization of rainwater over Suwon region during farming and non-farming periods

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Journal of Agricultural Chemistry and Environment 2013年第1期2卷 1-7页

作者： Min-kyeong Kim Jong-sik Lee Goo-Bok Jung Byong-Gu Ko Soon-Ik Kwon Min-Young Kim Kyu-Ho So Sun-Gang Yun Department of Agricultural Environment National Academy of Agricultural Science Rural Development Administration (RDA) Suwon Republic of Korea Dresearch Planning Division Rural Development Administration Suwon Republic of Korea

Recently, special attention has been givento acid rain and its problem to environment such as acid precipitation and air pollution in East *** the present study, rainwater samples werecollected from Apr to Oct (farming period) and from Nov to Mar (non-farming period) in 2009 ~ 2011. The samples were chemically characterized for the assessment of emission sources. Suwon region, a typical agricultural area in Gyeonggi province (South Korea) was chosen as a study site. The content of ionic species and theirtemporal variation were used forfactor analysis, which was used to presume the natural and anthropogenic sources depending upon the farming and non-farming periods. The cationsobserved during farming and non-farming periods were?> Na+> Ca2+> K+> H+> Mg2+and Na+> N?>Ca2+> H+= Mg2+> K+, respectively. The anions during farming and non-farming periods were?>?> Cl- and?>?> Cl-, respectively. While the amounts of sulfate, one of the major dissolved components of rainwater were 113.5 and 177.0 ueq.L-1, the ones of NSS-?(Non-Sea Salt sulfate) were 93.7 and 87.1% during farming and non-farming periods, respectively. The comparison of observed pH values (pHobs) with the theoretical pH values (pHthe) showed that the neutralization of rainwater considerably went along during farming and non-farming periods. The highest amountof rainfall throughout the year was310.5 mmin August and its corre sponding nitrogen loading was5.03 kg·ha-1. The major ion contents for crop growth, , Ca2+, K+, Mg2+, were 49.4, 5.5, 18.1,1.4 kg·ha-1from April to October. The major contributions to the existing chemical ions in rainwaters during farming and non-farming periods were from the natural sources (sea and soil) and the anthropogenic sources (human and animal waste, vehicular emission + fossil fuels combustion), respectively.

关键词： Acidity Discharge Nutrient Rainwater