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Limited data are available regarding the proper application time and long-term outcomes of extracorporeal membrane oxygenation (ECMO) in patients with cardiogenic shock. This cohort study appraised the clinical outcomes according to ECMO application without or before cardiopulmonary resuscitation (CPR) in patients with acute myocardial infarction (AMI) combined with cardiogenic shock.Between 2011 and 2015, a total of 13,104 patients with AMI were enrolled in a nationwide AMI registry. Eligible patients with cardiogenic shock, who underwent percutaneous coronary intervention, with a 3-year clinical follow-up, were analyzed. The 949 included patients were divided into two groups: no ECMO (n = 845) and ECMO application (n = 104). The ECMO group was further divided into ECMO without or before CPR (n = 11) and ECMO after CPR (n = 93).Significant differences were noted in major adverse cardiac events (MACEs) between the no ECMO and ECMO application groups during the 3-year follow-up (41.5% vs. 80.8%; p0.001). However, the ECMO without or before CPR group showed similar outcomes to the no ECMO group in 3-year MACEs (63.6% vs. 41.5%; p = 0.055). MACEs during 3 years of follow-up were significantly lower in the ECMO without or before CPR group than in the ECMO after CPR group (63.6% vs. 82.8%; p = 0.005).A significantly lower risk of major cardiac events in ECMO without or before CPR suggests that early application of ECMO can be a reasonable strategy to improve outcomes in patients with AMI complicated by cardiogenic shock.

Stable angina is a chronic, systemic disease with a wide range of associated symptoms and clinical outcomes. Prompt diagnosis can be challenging for clinicians. Typical chest pain caused by stable angina occurs when the myocardium receives inadequate oxygen, resulting in myocardial ischemia. Various diagnostic tools including non-invasive tests such as coronary computed tomographic angiography and image-based stress tests have evolved over the last decade. An important factor in the selection of the proper diagnostic test for stable angina is assessment of the pre-test probability in the event of possible coronary arterial stenosis. (Korean J Med 2021;96:218-224)

Purpose This study aimed to compare mortality rates after discharge between the patients with non-ST-elevation myocardial infarction (NSTEMI) and those with ST-elevation myocardial infarction (STEMI), and identify each mortality risk factors in these two types of myocardial infarction. Materials and Methods Between 2011 and 2015, 13105 consecutive patients were enrolled in the Korea Acute Myocardial Infarction-National Institute of Health registry (KAMIR-NIH); 12271 patients with acute myocardial infarction met the inclusion criteria and were further stratified into the STEMI (n=5828) and NSTEMI (n=6443) groups. The occurrence of mortality and cardiac mortality at 3 years were compared between groups, and the factors associated with mortality for NSTEMI and STEMI were evaluated. Results The comparison between these two groups and long-term follow-up outcomes showed that the cumulative rates of all-cause and cardiac mortality were higher in the NSTEMI group than in the STEMI group [all-cause mortality: 10.9% vs. 5.8%; hazards ratio (HR), 0.464; 95% confidence interval (CI), 0.359–0.600, p100 beats/min), no PCI, and low hemoglobin level were identified as the risk factors for 3-year mortality. Conclusion The NSTEMI group had higher mortality compared to the STEMI group during the 3-year clinical follow-up after discharge. Low LVEF and no PCI were the main risk factors for mortality in the NSTEMI group. In contrast, old age and renal dysfunction were the risk factors for long-term mortality in the STEMI group.

In this study, we identified several factors related to left ventricular remodeling (LVR) and examined the impact of LVR on the prognosis of patients with ST-elevated myocardial infarction and multivessel disease treated with complete (CR) or incomplete (IR) revascularization. LVR was defined as an LV end-diastolic diameter >55 mm. A total of 262 patients without LVR at presentation were followed up with echocardiography between 1 month and 1 year. The primary outcome was a composite of all-cause death (AD), MI, and heart failure (HF), referred to as a major adverse cardiovascular endpoint (MACE). Then, each variable was analyzed as a secondary outcome. Follow-up echocardiography identified 26 patients (9.9%) with LVR. LVR was associated with an initial LV ejection fraction 70 mg/dL. Survival analysis showed an association between LVR and adverse outcomes only in the IR group, in which the adjusted hazard ratio (HR) was increased for the MACE (HR = 3.22, 95% confidence interval (CI) = 1.19–8.71, p = 0.002) and HF (HR = 21.37, 95% CI = 4.47–102.09, p< 0.001), but not for the CR group. In STEMI with MVD, LVR within the first year after percutaneous coronary intervention was associated with worse outcomes in the IR but not the CR group.

The selection of appropriate contrast media (CM) remains an important issue in terms of renal preservation in patients with acute myocardial infarction (AMI) and renal impairment scheduled for percutaneous coronary intervention (PCI). We compared the clinical outcomes of patients with AMI and renal impairment, depending on the CM type (iso-osmolar CM [IOCM] vs. low-osmolar CM [LOCM]) that was used during PCI.From the Convergent Registry of Catholic and Chonnam University for Acute Myocardial Infarction, 3174 post-PCI patients with AMI and renal impairment were subdivided into two groups (IOCM [n = 2101] and LOCM [n = 1073]).Regarding in-hospital clinical outcomes, the IOCM group had a higher peak creatinine (Cr) level and lower "Cr differential" than the LOCM group. A higher proportion of dialysis was noted in the IOCM group. In 30-day clinical outcomes, the IOCM group showed higher incidence of new-onset heart failure (HF) but lower incidence of revascularization than the LOCM group. The differences in in-hospital and 30-day clinical outcomes were attenuated after inverse probability of treatment weighting, except for new-onset HF. All other variables in 30-day clinical outcomes, including all-cause death, non-fatal myocardial infarction, cerebrovascular accidents, stent thrombosis, and any dialysis events, were similar between the two groups.Iso-osmolar CM use did not prevent future incidence of dialysis compared to LOCM use in AMI patients with renal impairment.

Recurrent acute myocardial infarction (AMI) is an adverse cardiac event in patients with a first AMI. The predictors of recurrent AMI after the first AMI in patients who underwent successful percutaneous coronary intervention (PCI) have not been elucidated.We analyzed the data collected from 9,869 patients (63.2 ± 12.4 years, men:women = 7,446:2,423) who were enrolled in the Korea Acute Myocardial Infarction Registry-National Institute of Health between November 2011 and October 2015, had suffered their first AMI and had received successful PCI during the index hospitalization. Multivariable logistic regression analysis was performed to identify the independent predictors of recurrent AMI following the first AMI.The cumulative incidence of recurrent AMI after successful PCI was 3.6% (359/9,869). According to the multivariable logistic regression analysis, the significant predictive factors for recurrent AMI were diabetes mellitus, renal dysfunction, atypical chest pain, and multivessel disease.In this Korean prospective cohort study, the independent predictors of recurrent AMI after successful PCI for the first AMI were diabetes mellitus, renal dysfunction, atypical chest pain, and multivessel disease.

BACKGROUND: In the cause of increase the clinical research observational evidence on type 2 myocardial infraction (T2MI), the study compared the characteristics of T2MI and T1MI with respect to major adverse cardiac events (MACE) and mortality as long-term outcomes from a large, nationwide, prospective Korean cohort registry. METHODS: From 13,105 consecutively enrolled individuals in the Korea Acute Myocardial Infarction-National Institute of Health (KAMIR-NIH) registry between October 2011 and December 2015, 11,053 acute myocardial infarction (AMI) patients were divided into the T1MI (n=10,545) and T2MI (n=508) groups. All patients completed ≥3 years of follow-up. RESULTS: The Kaplan-Meier curve analysis and Cox proportional hazard regression models showed that the cumulative rate of MACE was similar between the 2 groups (11.4% vs. 13.4%, log-rank P=0.185) at 3 years. However, the T2MI group showed higher rates of all-cause death [12.6% vs. 9.4%, log-rank P=0.019; hazard ratio (HR), 1.42; 95% CI: 1.08–1.85; P=0.012] and non-cardiac death (3.5% vs. 5.3%, log-rank P=0.043; HR, 1.55; 95% CI: 1.01–2.37; P=0.043) than the T1MI group. Male sex (HR 1.540; 95% CI: 1.218–1.947, P100 beats/min; HR, 1.852; 95% CI: 1.436–2.388, P25 kg/m(2); HR, 0.644; 95% CI: 0.514–0.805, P

Background Noise has been a major issue in children due to its effect on emotional symptoms and sleep problems. The present study investigated the effect of noise on sleep and autonomic activity in children according to three variables, namely, road traffic noise, aircraft noise, and noise sensitivity (NS). Methods The study is epidemiological in nature. A total of 474 subjects of four elementary schools were evaluated in conjunction with the 2014 noise map data gathered from two metropolitan regions, Seoul and Ulsan, in South Korea. Each subject completed the children's sleep habits questionnaire, and heart rate variability (HRV) was recorded. Analysis of covariance was performed using monthly income as a covariate. Results Aircraft noise was associated with night waking (P = 0.047), whereas no significant association was observed between sleep and road traffic noise. After stratifying by NS, no significant results were obtained for road traffic noise. However, high levels of aircraft noise in the high-NS group were associated with high degrees of bedtime resistance (P = 0.049). In terms of HRV, no significant difference was observed in the results between groups. Conclusion Road traffic noise did not significantly alter sleep or autonomic activity in children, whereas aircraft noise exerted a negative effect on sleep. The findings suggest that the impact of noise on sleep in children varies depending on noise sources., Graphical Abstract

Real-world data on baseline characteristics, clinical practice, and outcomes of late presentation (12 to 48 h of symptom onset) in patients with ST-segment elevation myocardial infarction (STEMI) are limited.This study aimed to investigate real-world features of STEMI late presenters in the contemporary percutaneous coronary intervention (PCI) era.Of 13,707 patients from the Korea Acute Myocardial Infarction Registry-National Institutes of Health database, 5,826 consecutive patients diagnosed with STEMI within 48 h of symptom onset during 2011 to 2015 were categorized as late (12 to 48 h; n = 624) or early (12 h; n = 5,202) presenters. Coprimary outcomes were 180-day and 3-year all-cause mortality.Late presenters had remarkably worse clinical outcomes than early presenters (180-day mortality: 10.7% vs. 6.8%; 3-year mortality: 16.2% vs. 10.6%; both log-rank p 0.001), whereas presentation at ≥12 h of symptom onset was not independently associated with increased mortality after STEMI. The use of invasive interventional procedures abruptly decreased from the first (12 h) to the second (12 to 24 h) 12-h interval of symptom-to-door time ("no primary PCI strategy" increased from 4.9% to 12.4%, and "no PCI" from 2.3% to 6.6%; both p0.001). Mortality rates abruptly increased from the first to the second 12-h interval of symptom-to-door time (from 6.8% to 11.2% for 180-day mortality; from 10.6% to 17.3% for 3-year mortality; all p 0.05).Data from a nationwide prospective Korean registry reveal that inverse steep differences in the use of invasive interventional procedures and mortality rates were found between early and late presenters after STEMI. A multidisciplinary approach is required in identifying late presenters of STEMI who can benefit from invasive interventional procedures until further studied.

Background: Selecting angiotensin converting enzyme inhibitor (ACEI) or angiotensin II type I receptor blocker (ARB) in patients diagnosed as acute myocardial infarction (AMI) with non-obstructive coronary arteries (MINOCA) is not established. The purpose of this study is to compare the clinical effect of ACEI vs. ARB in MINOCA patients. Methods and results: A total of 273 patients between November 2011 to June 2015, diagnosed with MINOCA who were registered in the Korea Acute Myocardial Infarction Registry — National Institute of Health were enrolled. Patients were divided into ACEI (n = 112) and ARB groups (n = 161). The primary endpoint was cumulative incidence of major adverse cardiac events (MACE) defined as cardiac death, recurrent MI, any new revascularization during 2 years clinical follow-up. Secondary endpoint was heart failure requiring re-hospitalization. Propensity score matching analysis was done. The incidence of primary endpoint was similar (10.4% vs. 15.6%, HR: 0.65; 95% CI: 0.29–1.47; p = 0.301) among both groups. However, the incidence of recurrent MI was significantly lower in ACEI group compared to ARB group (2.1% vs. 10.4%, HR: 0.18, 95% CI: 0.04–0.86; p = 0.031). Conclusions: In the present study, the risk and incidence of MACE was similar between ACEI and ARB therapy in MINOCA patients. However, ACEI significantly reduced the risk of recurrent MI. Further larger scale multi-center randomized clinical trials are needed to clarify the proper use of renin–angiotensin–aldosterone system blocker in these patients.

The clinical efficacy of ticagrelor is questionable in East Asian populations. Patients with acute myocardial infarction (AMI) with multivessel disease (MVD) are considered as high risk patients who might benefit from ticagrelor treatment. The purpose of this study is to compare the clinical effect of ticagrelor and clopidogrel in AMI patients with MVD in Korea.A total of 2275 patients between November 2011 and June 2015, diagnosed with AMI with MVD after successful percutaneous coronary intervention who were registered in the Korea Acute Myocardial Infarction Registry - National Institute of Health (KAMIR-NIH) were enrolled. Patients were divided into ticagrelor (n = 837) and clopidogrel group (n = 1438). The primary endpoint was major adverse cardiac events (MACE) defined as cardiac death, non-fatal MI, target vessel revascularization, or ischemic stroke during 2 years of clinical follow-up. Secondary endpoints were thrombolysis in myocardial infarction (TIMI) major or minor bleeding, net clinical event composed of MACE and TIMI major bleeding, any repeated percutaneous coronary intervention, heart failure requiring re-hospitalization, and stent thrombosis. After propensity score matching analysis, the primary endpoint was lower in ticagrelor group compared to the clopidogrel group (8.6 % vs. 11.9 %; HR: 0.68; 95 % CI: 0.50-0.94; p = 0.018). The risk of TIMI major or minor bleeding was higher in the ticagrelor group (10.8 % vs. 4.8 %; HR: 2.51; 95 % CI: 1.68-3.76; p 0.001). The net clinical event was similar between ticagrelor and clopidogrel group (11.3 % vs. 13.6 %; HR 0.82; 95 % CI: 0.60-1.11; p = 0.195).Ticagrelor significantly reduced the risk of MACE than clopidogrel for AMI patients with MVD in Korea. However, the risk of TIMI major or minor bleeding was higher and the net clinical benefit was similar. Further large-scale multi-center randomized clinical trials are needed to clarify the proper use dual antiplatelet therapy in East Asian populations.

The State-Trait Anxiety Inventory (STAI), composed of two 20-item subscales (STAI-state and STAI-trait), has been increasingly used to assess anxiety symptoms in patients with Parkinson's disease (PD). However, the clinimetric attributes of the STAI under the statistical framework of the item-response theory (IRT) have not been fully elucidated within this population to date. We performed an IRT-based Rasch analysis of the STAI outcomes of patients with de novo PD from the Parkinson's Progression Markers Initiative database. The unidimensionality, Rasch model fit, scale targeting, separation reliability, differential item functioning, and response category utility of the STAI were statistically evaluated. A total of 326 (209 males, 117 females) patients without cognitive dysfunction were enrolled in our study. The original versions of the STAI-state and STAI-trait had acceptable separation reliability but lacked appropriate response category functioning, exhibited scale off-targeting, and several items demonstrated poor fit to the Rasch model. The response categories were reduced from four to three, and the rescored three-point TASI-trait demonstrated a marked improvement in clinimetric properties without a significant impact on unidimensionality and separation reliability. The rescored three-point version of the STAI-state required the additional removal of four misfitting items in order to improve the Rasch model fit. To our knowledge, this is the first study to assess the measurement properties based on the IRT of the STAI in patients with PD. Our Rasch analysis identified the components requiring possible amendments in order to improve the clinimetric attributes of the STAI.

Spontaneous spinal epidural hematoma is extremely rare. It can cause fatal complication such as permanent neurologic deficit. Even though the exact cause of epidural hematoma is not known in most cases, anticoagulation treatment is associated in some cases. In this situation, prompt reversal of anticoagulation and immediate decompression surgery is required. Seventy-year-old woman presesnted with sudden hemiplegia. She had history of hypertension, dyslipidemia, and paroxysmal atrial fibrillation and had taken antihypertensive agent, statin, and warfarin. She did not have any history of trauma and her international normalized ratio was within therapeutic range during follow-up and at the time of event. Physical examination revealed decreased right extremities’ motor and sensory function but cognitive function was normal. Detailed neurologic examination and spinal magnetic resonance imaging identified extensive, spontaneous spinal epidural hematoma. After the reversal of anticoagulation with vitamin K injection, the patient underwent emergent hematoma removal surgery and recovered completely. Our case suggests epidural hematoma should be considered in sudden hemiplegia patients with anticoagulation therapy. Immediate reversal of anticoagulation and decompression surgery can avoid neurologic deficit.

To the Editor, A 54-year-old man presented with frequent episodes of sudden palpitation. Twelve-lead electrocardiogram demonstrated narrow QRS complex tachycardia at a rate of 150/min. The initial part of the ST segment occasionally became deeper and sharper during the tachycardia (arrow, Fig. 1). A cardiac electrophysiological study was performed and the narrow QRS complex tachycardia was reproducibly induced by a single atrial extra-stimulus. The tachycardia intermittently changed at the initial part of the ST segment (arrow, Fig. 2A). Atrial activity at the high right atrium (HRA) always preceded those of the His bundle and coronary sinus (CS) during the first induced supraventricular tachycardia (SVT) with an atrial cycle length of 344 ms, but the retrograde atrial activation sequence in the CS electrogram changed occasionally. Simultaneous activation of the right anterolateral and left lateral accessory pathways (APs) deepened and sharpened the initial point of the ST segment compared to right anterolateral AP activation alone. Radiofrequency catheter ablation abolished conduction over the right side AP. A single ventricular extra-stimulus induced a second tachycardia (388 ms) with the earliest, consistent retrograde atrial activity at the distal CS (Fig. 2B). The earlier retrograde atrial activation at HRA and ST segment change were not present after radiofrequency catheter ablation of the right anterolateral AP. The exact locations of both APs are described in Fig. 3A and ​and3B.3B. We ablated the second AP at the left lateral wall using a transaortic approach. Ventriculoatrial conduction occurred through the atrioventricular node after catheter ablation of the two APs. Figure 1. Twelve-lead surface electrocardiogram (25 mm/sec, 10 mm/mV) during a spontaneous episode of paroxysmal tachycardia and four magnified beats of tachycardia (A, B). The initial part of the ST segment of the first and fourth beats (arrows) during tachycardia ... Figure 2. (A) Surface electrocardiogram (ECG) and intracardiac electrograms from the high right atrium (HRA), His bundle region (His), right ventricular apex (RVa), and coronary sinus (Cs) during the first induced supraventricular tachycardia (SVT) with a cycle ... Figure 3. (A, B) Proposed locations of the two accessory pathways (AP) and (C, D) their contribution to tachycardia. (C) The clinical SVT used the right anterolateral AP as a re-entry circuit and intermittently used the left lateral AP as a bystander but conduction ... Electrocardiographic or electrophysiologic findings that demonstrate the presence of multiple AP include (1) changing antegrade delta waves; (2) evidence of multiple retrograde atrial activation routes; and (3) orthodromic SVT with intermittent antegrade fusion complexes [1]. Concealed conduction through another pathway may not be apparent until the dominant pathway is ablated [2]. Detecting multiple APs requires detailed atrial mapping during programmed stimulation, and elimination of an apparent AP [3]. If the V-A interval or P-wave morphology changes during orthodromic tachycardia, the presence of additional AP should be suspected [4,5]. Although a single, fixed retrograde atrial activation pattern is observed in the presence of two or more AP, the presence of different retrograde atrial activation patterns documents the presence of multiple AP [1]. In our case, an additional AP was recognized by the appearance of more than one atrial breakthrough point during the first induced tachycardia. Intermittent changes in the retrograde atrial activation sequence occurred in the CS (from distal-to-proximal to proximal-to-distal), whereas retrograde atrial activation in the HRA was the earliest. The consistent earliest activation in the HRA suggests that clinical SVT uses the right anterolateral AP as a re-entry circuit and intermittently the left lateral AP as a bystander. Atrial fusion due to intermittent, simultaneous activation of the two AP changed the initial point of the ST segment on the surface electrocardiogram (Fig. 3C and ​and3D).3D). Careful attention to the ST segment during tachycardia could help identify multiple AP before an electrophysiologic study.

Background This study examined the long-term preventive effects of a case management service on suicide reattempts, and clarified the factors related to suicide reattempts. Methods We reviewed the medical records of suicide attempters who visited the emergency department of Ulsan University Hospital from August 28, 2013 to July 31, 2017. A 4-week case management service was provided to consenting participants, either face-to-face or by telephone. Using survival analysis, we analyzed differences in the time to the next emergency department visit for a suicide attempt according to whether participants completed the case management service. We also assessed which characteristics of participants were associated with suicide reattempts. Results We found no overall difference in time to suicide reattempt between case-managed participants and controls over the entire observation period (median period: 19 months). However, in the first 24 weeks after the initial suicide attempt, the case-managed group showed a longer time to reattempt than did the control group (log-rank test = 4.243; P = 0.039). A higher risk of reattempt was found among participants with the medical benefit type of health insurance compared to those with national health insurance (hazard ratio [HR], 5.134; P < 0.001) and among participants aged 20–39 compared to those aged ≥ 60 (HR, 3.502; P = 0.05). Conclusion Case management had only short-term benefits (within 24 weeks of initial suicide attempt). Risk factors for suicide reattempts were having a medical benefit health insurance and being aged 20–39 years., Graphical Abstract

Objective The present study aimed to examine the potential mediating effect of income level on the association between noise exposure and insomnia. Methods 706 individuals were evaluated in conjunction with 2014 noise map data from Seoul, South Korea. Cross-sectional analysis was performed to examine differences in noise level according to household income, while three separate logistic regression models were used to examine factors influencing insomnia. Odds ratios (ORs) were calculated after adjusting for depression, anxiety, auditory acuity and noise sensitivity in the first model. Analyses were adjusted for sociodemographic variables in the second model, lifestyle factors and medical illnesses in the third model. Results Noise level was significantly associated with an increased risk of insomnia in the low-income group, although no such association was observed in the high-income group. Groups exposed to >60 dB of noise (Lden; day-evening-night equivalent) exhibited a 1.79-fold increase in the incidence of insomnia relative to those exposed to

：A total of 447 adolescents who were recruited from a child and adolescent psychiatric clinic of university hospital completed a self-report questionnaire consisting of Korean Internet Addiction Self-scale (K-scale), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Korean-Attention-Deficit Hyperactivity Disorder Rating Scale (K-ARS), and Adolescent Happiness Index (AHI). They were classified into three internet user groups, non-addicted group (below or equal to 94), poten-tial risk group (95 to 107) and high risk group above or equal to 108) according to K-scale total score.

Chronic manganese (Mn) exposure often leads to impairments in fine motor and cognitive functions, particularly memory. However, the neural correlates of Mn-induced alterations in memory remain unclear. In the present study, we performed functional MRI (fMRI) with 2-back memory tests to assess the neural correlates of Mn-induced memory impairment in response to subclinical dysfunction in the working memory networks in welders exposed to Mn for extended periods of time. Within-group and between-group analyses revealed that brain activity in working memory networks was increased in welders with chronic Mn exposure during the 2-back verbal working memory task compared to healthy control individuals. Therefore, our fMRI findings indicate that welders might require more neural resources in working memory networks to compensate for subtle deficits in working memory and altered working memory processes, even if they performed the tasks at the same level as healthy control individuals.

ObjectiveaaThis study aimed to examine the effectiveness of quetiapine and the effects of dosage relates to its effectiveness on schizophrenia and schizoaffective disorder in a naturalistic setting in Korean people. MethodsaaThis study was a 24-week, open-label, non-comparative, naturalistic study of quetiapine in patients diagnosed with schizophrenia and schizoaffective disorder according to DSM-IV. We stratified the patients into mild [(clinical global impression severity (CGI-S)

We present the first report of fetal alcohol effect in a 12 year-old child in Korea. The mother had consumed 162 g of alcohol per week continuously during pregnancy. His first febrile seizure occurred before he was 1 year old, and became more frequent 2 years later. He started showing signs of right paraplegia when he was 3.5 years old and brain MRI revealed periventricular leucomalacia near the left ventricle. He was microcephalic and his growth was retarded. He was irritable, impatient, impulsive, and inattentive, and showed disinterest in school activities and aggressive and dangerous behavior. After the diagnosis of attention deficit/hyperactivity disorder was made, psychopharmacological treatment and family support was initiated. After 10 months, he still had intermittent ideas of reference, although the aggressive behavior, inattentiveness, and impulsivity had improved. Using this case study, we stress the importance of maternal alcohol history in patients with these characteristics.

We have studied stability in organic light-emitting diode depending on buffer layer and cathode. A transparent electrode of indium-tin-oxide(ITO) was used as an anode. An electron injection energy barrier into organic material is different depending on a work function of cathodes. Theoretically, the energy barriers for the electron injection are 1.2 eV, -0.1 eV, and 0.0 eV for Al, LiAl, and LiF/Al at 300 K, respectively. We considered the cases that holes are injected to organic light-emitting diode. The hole injection energy barrier is about 0.7 eV between ITO and TPD without buffer layer. For hole-injection buffer layers of CuPc and PEDOT:PSS, the hole injection energy barriers are 0.4 eV and 0.5 eV, respectively. When the buffer layer of CuPc and PEDOT:PSS is existed, we observed the effects of hole injection energy barrier, and a reduction of operating-voltage. However, in case of PVK buffer layer, the hole injection energy barrier becomes high(1.0 eV). Even though the operating voltage becomes high, the efficiency is improved. A device structure for optimal lifetime condition is ITO/PEDOT:PSS/TPD//LiAl at an initial luminance of .

Recently, Nanotechnology becomes a major issue in most part of industries. Nanotechnology is expected to develop various application products due to nano material mired composites is improved physical and electrical properties compared to conventional composites materials. Dielectric and insulation materials need to develop and improve like other field about nanotechnology. In this paper, we reported dielectric dispersion by size(no filler, , 500 nm, 10 nm), frequencies(60, 120, 1 kHz), and temperatures(). Dielectric constant of composites materials with filler shows higher than composites materials without filler and increased depending on rising temperatures in low frequency region. It was the effect that nano-filler and impurities in composites contributed to electrical conductivity. And dielectric properties depending on temperatures shows to change in low frequency region dramatically We analyzed interfacial polarization in low frequency region( Hz) and oriented polarization in high frequency region( Hz) on composites materials.

Maxwell-displacement-current (MDC) measuring technique has been applied for the investigation of monolayers of poly(vinyl alcohol)s bearing azobenzene side-chains (6Az5PVA) mixed with p-pentyl-p`-cyano-biphenyls (5CBs) on a water surface. For mixed monolayers containing trans-form 6Az5PVA and LCs, displacement current due to photo isomerization was not generated with alternative photo-irradiation with UV and svisible light. In contrast, for mixed monolaters containing cis-form 6Az5PVA and LCs, displacement current was generated. Finally, it was found that the alignment layers deposited in cis-form could photoregualte the orientation of LCs.

Organic photovoltaic properties were studied in and heterojunction structure by varying the organic layer thicknesses. Current density-voltage characteristics of organic photovoltaic cells were measured using Keithley 236 source-measure unit and a 500 W xenon lamp (ORIEL 66021) for a light source. From the analyses of current-voltage characteristics such as short-circuit current density, open-circuit voltage and power conversion efficiency, optimum thickness of the organic layer were obtained.⨀

We have investigated the effects of hole-injection buffer layer in organic light-emitting diodes using poly(3,4-ethylenedioxythiophene):poly(stylenesulfonate)(PEDOT:PSS) in a device structure of . Polymer PEDOT:PSS buffer layer was made by spin casting method. Current-voltage, luminance-voltage characteristics and efficiency of device were measured at room temperature with a variation of cathode materials; Al, LiF/Al, LiAl, and Ca/Al. The device with LiF/Al cathode shows an improvement of external quantum efficiency approximately by a factor of ten compared to that of Al cathode only device. Our observation shows that cathode is important in improving the efficiency of the organic light-emitting diodes.

Temperature (T) dependence of the sheet resistance (R/) has been investigated an the c-axis oriented thin films of the (Bi2212/Bi2201) mixed crystal with different molar fractions. The R/-T superconducting characteristic deteriorated with reduction of the Bi2212 fraction, and almost disappears at 48 mol% where a superconductor-to-insulator transition too k place, with the resistance on the normal state, RN/, reaching 4.1 kΩka at 80 K. This R/ value is close to the universal quantum number, h/(2e)≡ 6.5 kΩ predicted by the Kosterlitz-Thouless (KT) transition theory. The R/-T characteristics of the 48 mol% thin film can be elucidated as a competitive process of KT transition brought about by charge or vortex in the two-dimensional layer structure.

OBJECTIVE The aim of this study was to estimate the prevalence and correlates of mental disorders in Korean adults. METHODS Door to door household surveys were conducted with community residents aged 18-74 years from July 19, 2011, to November 16, 2011 (n=6,022, response rate 78.7%). The sample was drawn from 12 catchment areas using a multistage cluster method. Each subject was assessed using the Korean version of the World Health Organization Composite International Diagnostic Interview (CIDI) based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). RESULTS Lifetime and 12-month prevalence estimates were as follows: alcohol use disorders, 13.4% and 4.4%, respectively; nicotine use disorders, 7.2% and 4.0%, respectively; anxiety disorders, 8.7% and 6.8%, respectively; and mood disorders, 7.5% and 3.6%, respectively. The prevalence rates of all types of DSM-IV mental disorders were 27.6% and 16.0%, respectively. Being female; young; divorced, separated, or widowed; and in a low-income group were associated with mood and anxiety disorders after adjustment for various demographic variables, whereas being male and young were associated with alcohol use disorders. Higher income was not correlated with alcohol use disorder as it had been in the 2001 survey. CONCLUSION The rate of depressive disorders has increased since 2001 (the first national survey), whereas that of anxiety disorders has been relatively stable. The prevalence of nicotine and alcohol use disorders has decreased, and the male-to-female ratio of those with this diagnosis has also decreased.

ResultsZZA total of 209 participants (schizophrenia, 101 ; bipolar disorder, 49 ; healthy controls 59) were enrolled. Our scale showed high reliability and concurrent validity compared with the order subtest of the short form of the Weschler Adult Intelligence scale. Internal validity also was high (Cronbach’s alpha=0.904). Most items were easy to answer and highly discriminative. The test information curve showed our scale to be more informative in patients with low social cognition ability.