Se Hyun Kim

Dongguk University, Sŏul, Seoul, South Korea

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Publications (166)786.14 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Despite both depression and metabolic disturbances confer substantial burden of disease, natural course of depressive symptoms and the relationship with metabolic adversities have not examined. We explore associations between trajectories of depressive symptoms and metabolic disturbance, lifestyle factors and comorbidities. This retrospective cohort study included 13,745 subjects (8113 men and 5632 women) 40-59 years of age who underwent health examinations at the Seoul National University Hospital Healthcare System, Gangnam Center, in Korea. The median follow-up duration was 4.0 years. We estimated the mean trajectories of the Beck Depression Inventory scores using latent-class growth-curve analysis. We identified four distinctive trajectories of depressive symptoms in both sex. The probabilities of group membership were 35.1% (n=2374) in minimal, 47.4% (n=4545) in persistent-mild, 14.4% (n=987) in persistent-moderate, and 3.0% (n=207) in persistent-severe in men, and 36.3% (n=1883), 50.0% (n=3069), 12.3% (n=601) and 1.5% (n=79) in women. We found significant increasing trend in the prevalence of metabolic abnormalities in more severe depressive trajectory. The adjusted odds ratios of persistent-severe were significantly increased for the following variables: low HDL, hypertriglyceridemia, and metabolic syndrome (MetS) in men and hypertriglyceridemia, MetS in women, and smoking, alcohol consumption and lack of exercise in both genders. Medical and psychiatric histories were obtained using a self-reported questionnaire rather than formal diagnostic assessments. The higher level of depressive symptoms trajectory was associated with MetS, especially lipid abnormalities, and several modifiable lifestyle factors. Our findings provide important implications for developing health policy and guidelines for reducing depressive symptom burden. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of Affective Disorders 09/2015; 188:14-21. DOI:10.1016/j.jad.2015.08.024 · 3.38 Impact Factor
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    ABSTRACT: Poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT:PSS) was blended with polyethylene oxide (PEO) and polyvinyl alcohol (PVA) and composite film was cast. Additional solvents of dimethyl sulfoxide (DMSO) and ethylene glycol (EG) were mixed and their effects on electrical conductivity and structural changes were investigated. The electrical conductivity increased in response to the additional solvent, leading to an increase in the PEDOT ratio relative to the control. PEDOT:PSS/PEO composite film had a much higher electrical conductivity than PEDOT:PSS/PVA. When blended with PEO, the quinoid structure revealed by Raman spectroscopy increased relative to the PVA-blended case, indicating higher electrical conductivity. The current–voltage response and gas sensitivity showed much better performance in PEDOT:PSS/PEO/DMSO composite film. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42628.
    Journal of Applied Polymer Science 07/2015; 132(40). DOI:10.1002/app.42628 · 1.77 Impact Factor
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    ABSTRACT: We successfully fabricate high performance bottom-contact organic field-effect transistors (OFETs) using AgNW networks electrodes by spray deposition. The synthesized AgNWs have the dimension of 40-80 nm in diameter and 30-80 µm in length and were randomly distributed and interconnected to form a 3D hollow framework. The AgNWs film, deposited by spray coating, yielded an average optical transmittance of up to 88 % and a sheet resistance as low as 10 ohm/sq. For using AgNWs as source/drain electrodes of OFETs with bottom-contact configuration, the large contact resistance at AgNWs/organic channel remains critical issue for charge injection. To enhance charge injection, we fabricate semiconductor crystals on the AgNW using adsorbed residual poly(N-vinylpyrrolidone) layer. The resulting bottom-contact OFETs exhibit high mobility up to 1.02 cm2/Vs, and are similar to that of the top-contact Au electrodes OFETs with low contact resistance. A morphological study shows that the pentacene crystals coalesced to form continuous morphology on the nanowires, and were highly interconnected with those on the channel. These features contribute to efficient charge injection and encourage the improvement of the bottom-contact device performance. Furthermore, large contact area of individual AgNWs spreading out to the channel at the edge of the electrode also improves device performance.
    ACS Applied Materials & Interfaces 06/2015; 7(26). DOI:10.1021/acsami.5b02610 · 6.72 Impact Factor
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    ABSTRACT: Cisplatin is a potent chemotherapeutic agent, but its nephrotoxicity, which results in acute kidney injury (AKI), often limits its clinical application. Although many studies have attempted to target the mechanism responsible for its nephrotoxicity, no such method has been demonstrated to be effective in clinical trials. Recently, a dipeptidyl peptidase-4 (DPP4) inhibitor has been reported to have a renoprotective effect in a mouse model of cisplatin-induced AKI. Therefore, we will evaluate whether a DPP4 inhibitor protects the kidney from cisplatin-induced injury in humans. This is a single-center, prospective, randomized, double-blind, placebo-controlled trial. A total of 182 participants who are scheduled for cisplatin treatment will be enrolled and randomly assigned to receive either a DPP4 inhibitor (gemigliptin) or a placebo. Participants will take the study drugs for 8 days starting 1 day before cisplatin treatment. The primary outcome of interest is the incidence of AKI at 7 days after finishing treatment with cisplatin. The secondary outcomes include changes in serum creatinine levels and estimated glomerular filtration rates from baseline to 7 days after cisplatin treatment. This is the first clinical trial to investigate the effect of a DPP4 inhibitor on cisplatin-induced AKI. number NCT02250872, December 26, 2014.
    Trials 05/2015; 16(1):239. DOI:10.1186/s13063-015-0772-4 · 1.73 Impact Factor
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    ABSTRACT: The electrical stabilities of low-voltage organic field-effect transistors (OFETs) were improved by graftable fluorinated polymer (gPFS) layers and applying these layers onto poly(4-vinyl phenol)-based crosslinked dielectrics (cPVP). As a result, smooth and hydrophobic surface is formed and the dielectric film displayed a low leakage current density. The chemisorbed gPFS groups enabled the solution processing of an overlying 5,11-bis(triethylsilylethynyl)anthradithiophene (TES-ADT) semiconductor, which formed favorable terrace-like crystalline structures after solvent annealing. The top-contact OFETs showed superior operational stability compared to the cPVP-based OFETs. The hysteresis behavior in this top-contact OFET was negligible, and the off current of the transfer curve was one order of magnitude lower than the off current obtained from the cPVP-based OFET. The threshold voltage shift, measured after a sustained gate bias stress over 1 h, decreased significantly upon introduction of the hydrophobic gPFS treatment, the energetic barrier to creating charge trapping sites increased, and the trap distribution narrowed, as supported by a stretched exponential function model.
    Physical Chemistry Chemical Physics 05/2015; 17(26). DOI:10.1039/C5CP01909E · 4.49 Impact Factor
  • Cancer Research 05/2015; 75(9 Supplement):P6-08-33-P6-08-33. DOI:10.1158/1538-7445.SABCS14-P6-08-33 · 9.33 Impact Factor
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    ABSTRACT: This study assessed the relationship between thyroid-stimulating hormone (TSH) level and risk of depressive symptom in a population with no clinical or laboratory evidence of thyroid dysfunction. This retrospective cohort study included 13,017 subjects (7913 males and 5104 females), 17-84 years of age, who underwent health examinations at the hospital. Subjects had a Beck Depression Inventory (BDI) total score of ≤9 and fell within the normal range of free T4 levels at baseline. The association between gender-specific serum TSH tertile at baseline and the development of clinically significant depressive symptom (i.e., ≥19 BDI total score) on the follow-up visit was evaluated using the Cox proportional hazards model, with adjustment for demographic and life style factors. The risk of depressive symptom was increased among subjects with the highest tertile TSH level (adjusted hazard ratio [HR], 2.236; 95% confidence interval [CI], 1.443-3.466; p<0.001) as compared with subjects with the lowest tertile in females, but not in males. Even among patients with normal TSH levels, females in the lowest-normal TSH tertile had a higher risk of depressive symptoms (adjusted HR, 2.279; 95% CI, 1.456-3.567; p<0.001) than did those in the highest tertile. The TSH level as a continuous variable significantly predicted the depressive symptoms in females (adjusted HR, 1.402; 95% CI, 1.002-1.812; p=0.027). Our finding suggests that suboptimal thyroid function increases vulnerability to the occurrence of depressive symptom and represents a modifiable risk factor for depression in females. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Psychoneuroendocrinology 04/2015; 58:114-119. DOI:10.1016/j.psyneuen.2015.04.016 · 4.94 Impact Factor
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    ABSTRACT: Hypermethylation of the CpG island of p16 (INK4a) occurs in a significant proportion of colorectal cancer (CRC). We aimed to investigate its predictive role in CRC patients treated with 5-fluorouracil, leucovorin, irinotecan (FOLFIRI), and cetuximab. Pyrosequencing was used to identify KRAS mutation and hypermethylation of 6 CpG island loci (p16, p14, MINT1, MINT2, MINT31, and hMLH1) in DNA extracted from formalin-fixed paraffin-embedded specimens. Logistic regression and Cox regression were performed for analysis of the relation between methylation status of CIMP markers including p16 and clinical outcome. Hypermethylation of the p16 gene was detected in 14 of 49 patients (28.6%) and showed significant association with KRAS mutation (Fisher`s exact, P=0.01) and CIMP positivity (Fisher`s exact, P=0.002). Patients with p16-unmethylated tumors had significantly longer time to progression (TTP, median 9.0 vs 3.5 months; log-rank, P=0.001) and overall survival (OS, median 44.9 vs 16.4 months; log-rank, P=0.008) than those with p16-methylated tumors. Patients with both KRAS and p16 aberrancy (n=6) had markedly shortened TTP (median 2.8 months) compared to those with either KRAS or p16 aberrancy (n=11; median 8.6 months, P=0.021) or those with neither (n=32; median 9.0 months, P <0.0001). In multivariate analysis, KRAS mutation and p16 methylation showed independent association with shorter TTP (KRAS mutation HR=3.21, P=0.017; p16 methylation HR=2.97, P=0.027). Hypermethylation of p16 was predictive of clinical outcome in mCRC patients treated with cetuximab and FOLFIRI, irrespective of KRAS mutation.
    Cancer Research and Treatment 04/2015; DOI:10.4143/crt.2014.314 · 3.32 Impact Factor
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    ABSTRACT: The aim of this study was to evaluate the outcomes and patterns of recurrence in the different subtypes of breast cancer. We analyzed 1432 stage I-III breast cancer patients who had undergone surgery at Seoul National University Bundang Hospital between June 2003 and August 2011. Five subtypes were defined according to estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 (HER2), and Ki-67. Overall survival (OS) and breast cancer-free interval (BCFI) rates were estimated using the Kaplan-Meier method. Site-specific recurrence was estimated using Gray's test. The median follow-up period was 53 months. There were 22 local recurrences, 18 cases of contralateral breast cancer, 19 regional nodal recurrences, and 70 distant metastases. The 5-year BCFIs by subtype were luminal B-HER2 (+), 94.2 %; luminal A, 93.9 %; luminal B-HER2 (-), 91.4 %; HER2, 83.1 %; and triple-negative, 81.9 % (p < 0.001). Cases with the luminal A had a 5-year OS rate of 98.3 % that was the longest compared to those of cases with luminal B-HER2 (-), 95.8 %; luminal B-HER2 (+), 98.0 %; HER2, 90.8 %; and triple-negative, 89.9 % (p < 0.001). The triple-negative had a higher rate of local recurrence at the first site than others (p = 0.013). HER2 and triple-negative had higher rates of nodal recurrence at the first site than others (p < 0.001). The outcomes and patterns of site-specific recurrence in Korean breast cancer patients were different for each subtype. Defining recurrence patterns by breast cancer subtypes can help determine the appropriate method of surveillance and treatment.
    Breast Cancer Research and Treatment 04/2015; 151(1). DOI:10.1007/s10549-015-3390-7 · 3.94 Impact Factor
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    ABSTRACT: Charge traps in polymer gate dielectrics determine the electrical stability of organic field-effect transistors (OFETs) and polar alkoxy groups are well-known extrinsic charge traps. However, the actual location of intrinsic charge traps in nonpolar polymer gate dielectrics has been poorly understood yet. Here, we demonstrate that the skeletal structure of polymer chain plays an important role determining the electrical stability. To verify it, we prepared linear and branched polystyrene (l-PS and b-PS), and blended them, in which branched segments provide much larger free volume than the other segments. The current-insulating performance and field-effect mobility increased with decease of b-PS portion. In particular, the bias-stress stability was remarkably varied according to the change of b-PS portion even though all measurements excluded reactive components such as oxygen and water; the increase of b-PS resulted in time-dependent decay of mobility and threshold voltage under bias stress. This indicates that the branched segments in b-PS provides intrinsic and metastable charge trap sites. Our result suggests that the skeletal structure of polymeric chains in gate dielectric is one of the important factors affecting intrinsic long-term operational stability of OFET devices.
    The Journal of Physical Chemistry C 04/2015; 119(14):7670-7677. DOI:10.1021/acs.jpcc.5b01522 · 4.77 Impact Factor
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    ABSTRACT: To measure the prognostic significance of absolute monocyte count/absolute lymphocyte count prognostic score (AMLPS) in patients with gastric cancer. We retrospectively examined the combination of absolute monocyte count (AMC) and absolute lymphocyte count (ALC) as prognostic variables in a cohort of 299 gastric cancer patients who underwent surgical resection between 2006 and 2013 and were followed at a single institution. Both AMC and ALC were dichotomized into two groups using cut-off points determined by receiving operator characteristic curve analysis. An AMLPS was generated, which stratified patients into three risk groups: low risk (both low AMC and high ALC), intermediate risk (either high AMC or low ALC), and high risk (both high AMC and low ALC). The primary objective of the study was to validate the impact of AMLPS on both disease-free survival (DFS) and overall survival (OS), and the second objective was to assess the AMLPS as an independent prognostic factor for survival in comparison with known prognostic factors. Using data from the entire cohort, the most discriminative cut-off values of AMC and ALC selected on the receiver operating characteristic curve were 672.4/μL and 1734/μL for DFS and OS. AMLPS risk groups included 158 (52.8%) patients in the low-risk, 128 (42.8%) in the intermediate-risk, and 13 (4.3%) in the high-risk group. With a median follow-up of 37.2 mo (range: 1.7-91.4 mo), five-year DFS rates in the low-, intermediate-, and high-risk groups were 83.4%, 78.7%, and 19.8%, respectively. And five-year OS rates in the low-, intermediate-, and high-risk groups were 89.3%, 81.1%, and 14.4%, respectively. On multivariate analysis performed with patient- and tumor-related factors, we identified AMLPS, age, and pathologic tumor-node-metastasis stage as the most valuable prognostic factors impacting DFS and OS. AMLPS identified patients with a poor DFS and OS, and it was independent of age, pathologic stage, and various inflammatory markers.
    03/2015; 21(9):2668-76. DOI:10.3748/wjg.v21.i9.2668
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    ABSTRACT: Organic field-effect transistors (OFETs) were fabricated using polymer blended gate dielectrics in an effort to enhance the electrical stability against a gate bias stress. A poly(melamine-co-formaldehyde) acrylated (PMFA) gate dielectric layer with great insulating properties was blended with polypentafluorostyrene (PFS), a type of hydrophobic fluorinated polymer. Although the overall electrical performance dropped slightly due to the rough and hydrophobic surfaces of the blend films, at the blend ratio (10%), the OFET’s threshold voltage shift under a sustained gate bias stress applied over 3 h decreased remarkably compared with an OFET based on a PMFA dielectric alone. This behavior was attributed to the presence of the hydrophobic and electrically stable PFS polymer, which provided a low interfacial trap density between the gate dielectric and the semiconductor. A stretched exponential function model suggested that the energetic barrier to create trap states was high, and the distribution of energetic barrier heights was narrow in devices prepared with PFS.
    Organic Electronics 03/2015; 21. DOI:10.1016/j.orgel.2015.03.005 · 3.83 Impact Factor
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    ABSTRACT: We investigated the effects of the solvent boiling point on organic field-effect transistor (OFET) device performances in devices prepared using two newly synthesized anthradithiophene derivatives: 9,10-di(4'-pentylphenylethynyl)-anthra[2,3-b:6,7-b']dithiophene (DPPEADT) and 9,10-bi([9',9'-dimethyl-fluoren-2-ylethynyl])-anthra[2,3-b:6,7-b']dithiophene (DFEADT). DPPEADT exhibited a distinct crystalline morphology whereas DFEADT was amorphous. We characterized the relationship between the molecular structures, film morphologies, and OFET device performances in devices prepared using solvents having one of three different boiling points (chlorobenzene, 1,2-dichlorobenzene, and 1,2,4-trichlorobenzene). 1,2,4-Trichlorobenzene, which provided the highest boiling point among the solvents tested and acted as a good solvent for DPPEADT, significantly improved the field-effect mobilities of DPPEADT devices up to 0.16 cm(2)/V by enhancing the crystallinity of the film. OFETs based on amorphous DFEADT films prepared using the three solvents did not provide enhanced electrical performances. The differences between the transistor performances were attributed to the degree of pi-overlap, the molecular structures, and the morphological properties of the films.
    Dyes and Pigments 03/2015; 114:60-68. DOI:10.1016/j.dyepig.2014.10.027 · 3.97 Impact Factor
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    ABSTRACT: Evidences suggest an association between leukocytosis and thrombotic or hemorrhagic complication in polycythemia vera (PV) and essential thrombocythemia (ET), but clinical implication is not well known. To evaluate whether leukocyte burden during follow-up is related to thrombotic or hemorrhagic events in PV and ET. We retrospectively analyzed patients with PV or ET treated at Seoul National University Bundang Hospital, Korea. Time-weighted averages of leukocytes during the follow-up period were defined as leukocyte burden and were calculated for each patient and compared between patient subgroups. In each patient with events, leukocyte burden for the 3-month period before the event was compared with that for the entire follow-up period. In 102 patients with PV or ET, 35 events (16 thrombotic, 19 hemorrhagic) occurred in 29 patients (median follow-up, 54months). Leukocyte burden were significantly higher in patients with events than in event-free patients (12,015×10(3) /μL vs. 9,567×10(3)/μL, P=0.003). The difference was more prominent in ET patients than in PV patients, and in patients with hemorrhagic events than in those with thrombotic events. In patients with events, the leukocyte burden in the pre-event period was higher than in the entire follow-up period (16,767×10(3)/μL vs. 12,015×10(3)/μL, P=0.002). In all patients, leukocyte burden during entire follow-up period of 11,000×10(3)/μL or higher was an independent risk factor for vascular events. In PV or ET patients, leukocyte burden during disease course is related to increased incidence of thrombotic or hemorrhagic events. Copyright © 2015. Published by Elsevier Ltd.
    Thrombosis Research 02/2015; 135(5). DOI:10.1016/j.thromres.2015.02.023 · 2.45 Impact Factor
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    ABSTRACT: Platinum-based doublet chemotherapy is the treatment of choice for patients with non-small cell lung cancer (NSCLC), however, the role of a platinum-based doublet as second-line therapy after failure of an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) for NSCLC patients has not yet been elucidated. The purpose of this study was to compare the clinical efficacy of pemetrexed versus a platinum-based doublet as second-line therapy after failure of EGFR TKI used as first-line therapy for NSCLC patients with EGFR mutations. We designed a multicenter retrospective cohort study of 314 NSCLC patients with EGFR mutations who received an EGFR TKI as first-line palliative chemotherapy. Our analysis included 83 patients who failed EGFR TKI therapy and received second-line cytotoxic chemotherapy. Forty-six patients were treated using a platinum-based doublet and 37 patients were treated using singlet pemetrexed. The overall response rates (RRs) of patients receiving a platinum-based doublet and patients receiving pemetrexed were17.4% and 32.4%, respectively (P=0.111). The median progression-free survival (PFS) of patients receiving pemetrexed was significantly longer than that of patients receiving a platinum-based doublet (4.2 months vs. 2.7 months, respectively; P=0.008). The hazard ratio (HR) was 0.54 (95% confidence interval [CI], 0.34-0.86;P=0.009). s Our retrospective analysis found that second-line pemetrexed singlet therapy provided significantly prolonged PFS compared to second-line platinum-based doublet chemotherapy for NSCLC patients with EGFR mutations who failed first-line EGFR TKI. Conduct of prospective studies for confirmation of our results is warranted.
    Cancer Research and Treatment 02/2015; DOI:10.4143/crt.2014.244 · 3.32 Impact Factor
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    ABSTRACT: Solution-processed organic field effect transistors (OFETs), which are amenable to facile large-area processing methods, have generated significant interest as key elements for use in all-organic electronic applications aimed at realizing low-cost, lightweight, and flexible devices. The low performance levels of n-type solution-processed bottom-contact OFETs unfortunately continue to pose a barrier to their commercialization. In this study, we introduced a combination of CVD-grown graphene source/drain (S/D) electrodes and fullerene (C60) in a solution-processable n-type semiconductor toward the fabrication of n-type bottom-contact OFETs. The C60 coating in the channel region was achieved by modifying the surface of the oxide gate dielectric layer with a phenyl group-terminated self-assembled monolayer (SAM). The graphene and phenyl group in the SAMs induced π-π interactions with C60, which facilitated the formation of a C60 coating. We also investigated the effects of thermal annealing on the reorganization properties and field-effect performances of the overlaying solution-processed C60 semiconductors. We found that thermal annealing of the C60 layer on the graphene surface improved the crystallinity of the face-centered cubic (fcc) phase structure, which improved the OFET performance and yielded mobilities of 0.055 cm(2) V(-1) s(-1). This approach enables the realization of solution-processed C60-based FETs using CVD-grown graphene S/D electrodes via inexpensive and solution-process techniques.
    Physical Chemistry Chemical Physics 02/2015; 17(9). DOI:10.1039/c4cp05787b · 4.49 Impact Factor
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    Sooman Lim · Keun Hyung Lee · Hyekyoung Kim · Se Hyun Kim
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    ABSTRACT: Nanocomposite gate insulators consisting of (Ba, Sr)TiO3 (barium strontium titanate; BST) nanoparticles and crosslinked poly(4-vinyl phenol) (PVP) polymers were fabricated. Well-dispersed nanocomposite films were prepared by optimizing the BST nanoparticle size sorting process (ultrasound crushing and centrifuge method). The size-sorted BST nanoparticles (∼30 nm in size) were homogeneously mixed in the PVP host polymer in various BST contents, from 0 to 70 wt%, to tune the dielectric constant (κ) of the resulting nanocomposite films. The composite films exhibit three-fold increase in the κ value from 3.9 to 11.3. The physical properties including leakage current and surface roughness of the composites were also measured as a function of the BST loading content and particle dispersion. The relationship between these properties and the electrical performance of the corresponding organic thin film transistor were explored.
    Organic Electronics 02/2015; 17:144-150. DOI:10.1016/j.orgel.2014.11.026 · 3.83 Impact Factor
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    ABSTRACT: The electrical performance of triethylsilylethynyl anthradithiophene (TES-ADT) organic field-effect transistors (OFETs) was significantly affected by dielectric surface polarity controlled by grafting hexamethyldisilazane and dimethyl chlorosilane-terminated polystyrene (PS-Si(CH3)2Cl) to 300-nm-thick SiO2 dielectrics. On the untreated and treated SiO2 dielectrics, solvent-vapor annealed TES-ADT films contained millimeter-sized crystals with low grain boundaries (GBs). The operation and bias stability of OFETs containing similar crystalline structures of TES-ADT could be significantly increased with a decrease in dielectric surface polarity. Among dielectrics with similar capacitances (10.5-11 nF cm−2) and surface roughnesses (0.40-0.44 nm), the TES-ADT/PS-grafted dielectric interface contained the fewest trap sites and therefore the OFET produced using it had low-voltage operation and a charge-carrier mobility ∼1.32 cm2 V−1 s−1, on-off current ratio >106, threshold voltage ∼0 V, and long-term operation stability under negative bias stress.
    Organic Electronics 02/2015; 17:87-93. DOI:10.1016/j.orgel.2014.11.022 · 3.83 Impact Factor
  • Moon Sung Kang · Jeong Ho Cho · Se Hyun Kim
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    ABSTRACT: This chapter describes the progress in the development of electrolyte-gated Organic thin-film transistors (OTFTs) toward the achievement of low-driving-voltage, flexible, and solution-processable electronics. This discussion begins with a basic explanation of the electrolyte-gated transistor operation mechanism, followed by an introduction of the various electrolyte materials employed in these devices. The electrical properties of electrolyte-gated transistors and their circuit applications are subsequently introduced. Two distinct gating mechanisms can drive the generation of a large current in the semiconducting layer in contact with an electrolyte gate dielectric material: electric double-layer gating or electrochemical gating. Several types of ionic liquid have been employed as gate dielectrics in OTFTs. The characteristics of ionic liquids that benefit the development of high performance OTFTs are frequently accompanied by fluid properties that reduce the practicality of using an ionic liquid in an electronic device.
    Large Area and Flexible Electronics, 01/2015: pages 253-274; , ISBN: 9783527336395
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    ABSTRACT: We investigated differential patterns of hallucinatory experiences between nonclinical and clinical samples. A total of 223 nonclinical individuals (108 females) and 111 subjects with schizophrenia (54 females) completed the Launay-Slade Hallucination Scale-Revised (LSHS-R) and Perceptual Aberration Scale (PAS). The Minnesota Multiphasic Personality Inventory-2 (MMPI-2) was used for the nonclinical group, and the Positive and Negative Syndrome Scale (PANSS) hallucination item was used for the clinical group. Cronbach׳s alpha values showed good internal consistency for the LSHS-R. In the two groups, significant associations were found between LSHS-R and PAS scores. Two factors were extracted through a principal component analysis (PCA) in the nonclinical group, and three factors were identified in the clinical group. The results of a hierarchical cluster analysis (HCA) revealed that a perception-cognition dimension was clear cluster discriminating element for the nonclinical group, whereas alterations in perception-cognition dimension were characteristic in cluster structure of the clinical group. Our findings suggest that the nature of hallucinatory experiences may differ qualitatively between a nonclinical population and subjects with schizophrenia. Perceptual or cognitive aberrations may add a psychopathologic dimension to hallucinatory experiences. Exploring the internal structure of hallucinatory experiences may provide explanatory insight into these experiences in the general population. Copyright © 2015. Published by Elsevier Ireland Ltd.
    Psychiatry Research 01/2015; 226(1). DOI:10.1016/j.psychres.2014.12.051 · 2.47 Impact Factor

Publication Stats

2k Citations
786.14 Total Impact Points


  • 2014–2015
    • Dongguk University
      Sŏul, Seoul, South Korea
    • Seoul National University Bundang Hospital
      Sŏul, Seoul, South Korea
  • 2013–2015
    • Yeungnam University
      • Department of Nano, Medical and Polymer Materials
      Gyeongsan, Gyeongsangbuk-do, South Korea
    • University of Minnesota Duluth
      • Department of Chemistry and Biochemistry
      Duluth, Minnesota, United States
  • 2009–2015
    • Kyung Hee University
      • Graduate School of East-West Medical Science
      Sŏul, Seoul, South Korea
  • 2006–2014
    • Seoul National University
      • • Medical Research Center
      • • Department of Biochemistry and Molecular Biology
      Sŏul, Seoul, South Korea
  • 2008–2013
    • Yonsei University
      • • Department of Internal Medicine
      • • Division of Medical Oncology
      Sŏul, Seoul, South Korea
  • 2006–2013
    • Seoul National University Hospital
      • Department of Neuropsychiatry
      Sŏul, Seoul, South Korea
    • Pohang University of Science and Technology
      • Department of Chemical Engineering
      Antō, North Gyeongsang, South Korea
  • 2007–2012
    • Yonsei University Hospital
      • Department of Internal Medicine
      Sŏul, Seoul, South Korea
  • 2003
    • CHA University
      • College of Medicine
      Sŏul, Seoul, South Korea