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On-the-fly dopant redistribution in a silicon nanowire p-n junction

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Nano Research 2017年第8期10卷 2845-2855页

作者： Dong-II Moon Myeong-Lok seol Jin-woo Han M. Meyyappan Center for Nanotechnology NASA Ames Research Center Moffett Field CA 94035 USA

Dopant redistribution in a silicon nanowire （SiNW） p-n junction is found to occur owing to self-heating effects. A SiNW is doped to form back-to-back diodes and is thermally isolated by an oxide layer on its bottom side and by air on the other sides. When a high level of current flows, the inner body temperature is found to increase enough to cause dopant diffusion and even to reach the silicon melting point due to Joule heating. This experimentally observed electrothermal behavior is also validated through numerical simulation. The conductivity change is dependent on the total power density and the change becomes permanent once the device suffers self-heating beyond a threshold point. Finally, the dopant redistribution is directly visualized using scanning capacitance microscopy for the first time.

关键词： nanowire degradation Joule heating dopant redistribution scanning capacitance microscopy

Evaluation of non-ampullary duodenal polyps: Comparison of non-neoplastic and neoplastic lesions

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World Journal of Gastroenterology 2010年第43期16卷 5474-5480页

作者： Sung Hoon Jung woo Chul Chung Eun Jung Kim seol Hye Kim Chang Nyol Paik Bo In Lee Young seok Cho Kang-Moon Lee Department of Internal Medicine College of Medicine The Catholic University of Korea

AIM: To evaluate duodenal polyps, divided into nonneoplastic and neoplastic lesions. In addition, the clinical characteristics of duodenal hyperplastic polyps are determined. METHODS: We analyzed medical records of 50 114 consecutive patients submitted to for first diagnostic esophago-gastroduodenoscopy between January 2004 and December 2009. We excluded lesions on the ampulla of Vater and submucosal tumors. We studied 510 cases that were diagnosed endoscopically with duodenal polyps and enrolled a total of 221 cases that had undergone tissue biopsy. We analyzed the differences between non-neoplastic and neoplastic lesions, and determined the clinical features of duodenal hyperplastic polyps. RESULTS: Non-neoplastic lesions were found in 196 patients and neoplastic lesions in 25 patients. On uni-variate analysis, there were significant differences in shape, location, and size. Polyps more than 10 mm in diameter or polyps in the second portion had independent risk factors for being neoplastic lesions, as identified by multivariate analysis. In 23 cases of hyperplastic polyps (79.3%), they were accompanied by gastroduodenal pathology, which was possibly associated with Helicobacter pylori . CONCLUSION: Polyps of more than 10 mm or polyps in the second portion of the duodenum should be evaluated by histological examination.

关键词： Duodenum Polyp Helicobacter pylori

Cycloaddition of CO_2 and propylene oxide by using M(HBTC)(4,4'-bipy)·3DMF(M=Ni,Co,Zn) metal-organic frameworks

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Chinese Journal of Catalysis 2018年第8期39卷 1311-1319页

作者： seol-Hee Kim Robin Babu Dong-woo Kim Wonjoo Lee Dae-Won Park Division of Chemical and Biomolecular Engineering Pusan National University Busan 609-735 Korea Korea Research Institute of Chemical Technology Ulsan 681-802 Korea

Three pillar-layered metal-organic frameworks（MOFs） based on M（HBTC）（4,4＇-bipy）.3DMF（M =Ni, Co, and Zn; HBTC = 1,3,5-benzenetricarboxylic acid, 4,4＇-bipy = 4,4′-bipyridine） were synthesized using a solvothermal method. Zn（HBTC）（4,4＇-bipy）.3DMF was synthesized for the first time using both a solvothermal and microwave method, and subsequently characterized by various physicochemical methods. The structure of M（HBTC）（4,4＇-bipy）.3DMF consisted of honeycomb grid layers of M2＋ ions and BTC units, which were further linked by the 4,4＇-bipy pillars to form a three-dimensional highly porous framework. All the MOFs displayed excellent synergistic catalytic properties with alkyl ammonium halides（TBAX） in the solventless fixation of CO_2 with epoxides to produce cyclic carbonates. The catalytic activities of these MOFs followed the trend Zn Co Ni,which was explained by the acid-base bifunctional properties. The microwave-synthesized Zn（HBTC）（4,4＇-bipy）.3DMF material exhibited physical, chemical, and catalytic properties that were similar to those of the catalyst obtained using a conventional solvothermal synthesis. The scope of various parameters, including recyclability, was studied, and a plausible reaction mechanism was suggested.

关键词： M(HBTC)(4,4'-bipy)·3DMF(M=Ni,Co,Zn) Microwave method Carbon dioxide Epoxide Cyclic carbonate

Diagnostic delay in inflammatory bowel disease increases the risk of intestinal surgery

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World Journal of Gastroenterology 2017年第35期23卷 6474-6481页

作者： Dong-won Lee Ja seol Koo Jung Wan Choe Sang Jun Suh Seung Young Kim Jong Jin Hyun Sung woo Jung Young Kul Jung Hyung Joon Yim Sang woo Lee Division of Gastroenterology and Hepatology Department of Internal MedicineKorea University Ansan Hospital

AIM To investigate the factors affecting diagnostic delay and outcomes of diagnostic delay in inflammatory bowel disease(IBD) METHODS We retrospectively studied 165 patients with Crohn's disease(CD) and 130 patients with ulcerative colitis(UC) who were diagnosed and had follow up durations > 6 mo at Korea University Ansan Hospital from January 2000 to December 2015. A diagnostic delay was defined as the time interval between the first symptom onset and IBD diagnosis in which the 76^(th) to 100^(th) percentiles of patients were *** The median diagnostic time interval was 6.2 and 2.4 mo in the patients with CD and UC, respectively. Among the initial symptoms, perianal discomfort before diagnosis(OR = 10.2, 95%CI: 1.93-54.3, P = 0.006) was associated with diagnostic delays in patients with CD; however, no clinical factor was associated with diagnostic delays in patients with UC. Diagnostic delays, stricturing type, and penetrating type were associated with increased intestinal surgery risks in CD(OR = 2.54, 95%CI: 1.06-6.09; OR = 4.44, 95%CI: 1.67-11.8; OR = 3.79, 95%CI: 1.14-12.6, respectively). In UC, a diagnostic delay was the only factor associated increased intestinal surgery risks(OR = 6.81, 95%CI: 1.12-41.4).CONCLUSION A diagnostic delay was associated with poor outcomes, such as increased intestinal surgery risks in patients with CD and UC.

关键词： Diagnostic delay Intestinal surgery Inflammatory bowel disease Crohn’s disease Ulcerative colitis

Effect of the glyceryl monooleate-based lyotropic phases on skin permeation using in vitro diffusion and skin imaging

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Asian Journal of Pharmaceutical Sciences 2014年第6期9卷 324-329页

作者： Dae Gon Lim Won-wook Jeong Nam Ah Kim Jun Yeul Lim seol-Hoon Lee woo Sun Shim Nae-Gyu Kang Seong Hoon Jeong College of Pharmacy Dongguk University-SeoulGoyangGyeonggi 410-820Republic of Korea LG Household&Health Care Daejeon 305-343Republic of Korea

Glyceryl monooleate(GMO)is a polar lipid that can exist in various liquid crystalline phases in the presence of different amounts of *** is regarded as a permeation enhancer due to its amphiphilic *** phases of GMO/solvent system containing sodium fluorescein were prepared to compare permeability using confocal laser scanning microscopy(CLSM).GMO was melted in a vial in a water bath heated to 45℃.Propylene glycol and hexanediol were homogeneously dissolved in the melted *** fluorescein in aqueous solution was diluted to various ratios and thoroughly mixed by an ultrasonic *** GMO/Solvent system with fluorescein was applied onto the epidermal side of excised pig skin and incubated *** was performed to observe how the GMO/solvent system in its different phases affect skin *** and lamellar phase formulations enhanced the fluorescein permeation through the stratum corneum.A solution system had the weakest permeability compared to the other two *** to the amphiphilic nature of GMO,cubic and lamellar phases might reduce the barrier function of stratum corneum which was observed by CLSM as fluorescein accumulated in the *** on the results,the glyceryl monooleate lyotropic mixtures could be applied to enhance skin permeation in various topical and transdermal formulations.

关键词： Confocal microscopy Imaging Glyceryl monooleate Skin permeation Cubic phase Lamellar phase

What is the real practice of exercise echocardiographic testing in asymptomatic patients with severe aortic stenosis？

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Chinese Medical Journal 2013年第24期126卷 4649-4654页

作者： Eun Jeong Cho Sung-Ji Park Jung-Eun Song seol-Hwa Kim Yung-Joo Lee Ji-Hye Gakt Sung-A Chang Sang-Chol Lee Seung woo Park Division of Cardiology Department of Internal MedicineCardiovascular Imaging Center Cardiac and Vascular CenterSamsung Medical Center Sungkyunkwan University School ofMedicine Seoul Republic of Korea

Background Although exercise testing has been suggested to help predict clinical outcome, limited data are available to guide how exercise Doppler echocardiography （ECG） can be used clinically in asymptomatic patients with aortic stenosis （AS）. The aim of this study was to assess the clinical value of exercise echocardiographic testing in asymptomatic patients with severe AS. Methods Symptom-limited treadmill exercise testing using the modified Bruce protocol was performed in 31 asymptomatic patients （mean age （62＋11） years） with severe AS （aortic valve area 〈1 cm2, peak aortic velocity （AV Vmax）〉4 m/sec, or a mean transaortic pressure gradient （AV mean PG）〉40 mmHg （1 mmHg=0.133 kPa）） with normal left ventricular （LV） systolic function （LV ejection fraction （EF）〉50%）. Clinical symptoms, vital signs, ECG, and Doppler hemodynamics were obtained during and/or immediately after exercise. Results Aortic valve replacement （AVR） was performed in 18 patients during follow-up. The patients who had AVR exhibited higher baseline AV mean PG （51 （35-84） vs. 44 （25.2-57.0） mmHg; P=0.031）. There were no significant differences between the AVR group and non-AVR group including exercise duration （7.47 （2.32-11.59） vs. 7.25 （4.06- 10.52） minutes, P=0.917）, exercise capacity （10.1 （4.6-12.8） vs. 10.1 （7.0-12.8） metabolic equivalents, P=0.675）, and an increment in AV mean PG by exercise （18.5 （3.2-48.0） vs. 12.6 （4.4-32.1） mmHg, P=0.366）. Univariate regression analysis revealed that independent determinant of AVR was the baseline AV mean PG （P=-0.031）. Conclusions Although additional value of exercise ECG was demonstrated, baseline transaortic mean pressure gradient is the major determinant of AVR. Further large-scale prospective studies are required to determine whether surgery should be recommended in the presence of an abnormal exercise ECG in asymptomatic severe AS.

关键词： aortic stenosis exercise echocardiography asymptomatic, aortic valve replacement

Development of enterohepatic fistula after embolization in ileal gastrointestinal stromal tumor: A case report

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World Journal of Gastroenterology 2013年第43期19卷 7816-7819页

作者： Yun Ho Lee Ja seol Koo Chang Ho Jung Sang Yoon Chung Jae Joong Lee Seung Young Kim Jong Jin Hyun Sung woo Jung Rok Seon Choung Sang woo Lee Jai Hyun Choi Division of Gastroenterology Department of Internal MedicineKorea University Ansan Hospital516 Gojan-dongDanwon-guAnsan-siGyeonggi-do 425-707South Korea

Gastrointestinal stromal tumor(GIST)is a rare mesenchymal tumor of the gastrointestinal tract that has been associated with the formation of fistulas to adjacent organs in few case ***,GIST with enterohepatic fistula has not been *** we report the case of an enterohepatic fistula that occurred after embolization of a liver mass originating in the distal *** 87-year-old woman was hospitalized for *** initial conventional endoscopy,a bleeding focus in the gastrointestinal tract was not *** of massive hematochezia,enteroscopy was performed through the anus.A protruding,ulcerative mass was found in the distal ileum that was suspected to be the source of the bleeding;a biopsy sample was *** was not successful in controlling the bleeding;therefore,embolization was *** embolization,the patient developed a high fever and severe abdominal tenderness with rebound ***-up abdominopelvic computed tomography revealed an enterohepatic fistula between the liver and distal *** fistula was treated surgically by segmental resection of the distal ileum and unlooping of the liver mass.

关键词： Gastrointestinal stromal tumor Enterohepatic fistula Therapeutic embolization Bleeding Ileal gastrointestinal stromal tumor

乳腺癌患者连续PET/CT显像和MRI预测肿瘤的分化程度

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中华核医学与分子影像杂志 2018年第11期38卷 774-775页

作者：唐军 Joon Ho Choi Ilhan Lim woo Chul Noh Hyun-Ah Kim Min-Ki Seong Seonah Jang Hyesil seol Hansol Moon Byung Hyun Byun Byung Il Kim Chang woon Choi Sang Moo Lim 上海交通大学医学院附属苏州九龙医院核医学科 Department of Nuclear Medicine Korea Cancer Center Hospital Korea Institute of Radiological and Medical Sciences (KIRAMS)

目的利用乳腺癌患者连续PET/CT显像和MRI所得的参数评价肿瘤的分化程度。方法回顾性研究78例乳腺癌患者,患者均行连续的PET/CT显像和MRI[注射;F-脱氧葡萄糖（FDG）后1 h和2 h分别行PET/CT显像,随后立刻行MRI检查]。PET/CT显像后计算1 h... 详细信息

目的利用乳腺癌患者连续PET/CT显像和MRI所得的参数评价肿瘤的分化程度。方法回顾性研究78例乳腺癌患者,患者均行连续的PET/CT显像和MRI[注射;F-脱氧葡萄糖（FDG）后1 h和2 h分别行PET/CT显像,随后立刻行MRI检查]。PET/CT显像后计算1 h和2 h FDG的最大标准摄取值(SUV;1和SUV;2)、代谢肿瘤体积（MTV）和总病灶糖酵解（TLG）。动态对比增强MRI参数用动态增强曲线进行分析。对有关表观弥散系数（ADC）值的弥散加权成像（DWI）进行评价。组织学分级为1级和2级的乳腺癌归为低等级肿瘤,3级的归为高等级肿瘤。结果 78例乳腺癌患者的病灶组织学分级属3级,2级和1级的分别为45、26和7个病灶。高等级肿瘤患者的平均ADC值（0.99±0.19）低于低等级肿瘤患者的平均ADC值（1.12±0.32;P=0.007）。高等级肿瘤患者的SUV;1、MTV2.5[平均标准摄取值(SUV;)取2.5时的MTV]和TLG2.5(SUV;取2.5时的TLG)值要高于低等级肿瘤患者[SUV;1:7.92±4.5和6.19±3.05, P=0. 09, MTV2.5:7.90±9.32和4.38±5.10,P=0.095;TLG2.5:40.83±59.17和19.66±26.08, P=0.082]。但高、低等级肿瘤患者间的其他参数差异无统计学意义。受试者工作特征（ROC）曲线分析发现高等级肿瘤的平均ADC值曲线下面积最大,达到0.681（95%CI:0.566～0.782）。结论在乳腺癌PET显像和MRI的多种功能性参数中,较低的平均ADC值也许能预测肿瘤较差的分化程度。

关键词：乳腺癌组织学分级 FDG-PET 动态对比增强MRI 弥散加权成像MRI