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BACKGROUND Many mood disorder patients experience seasonal changes in varying degrees. Studies on seasonality have shown that bipolar disorder has a higher prevalence rate in such patients; however, there is limited research on seasonality in early-onset mood disorder patients. This study estimated the prevalence of seasonality in early-onset mood disorder patients, and examined the association between seasonality and mood disorders. METHODS Early-onset mood disorder patients (n = 378; 138 major depressive disorder; 101 bipolar I disorder; 139 bipolar II disorder) of the Mood Disorder Cohort Research Consortium and healthy control subjects (n = 235) were assessed for seasonality with Seasonality Pattern Assessment Questionnaire (SPAQ). RESULTS A higher global seasonality score, an overall seasonal impairment score, and the prevalence of seasonal affective disorder (SAD) and subsyndromal SAD showed that mood disorder subjects had higher seasonality than the healthy subjects. The former subject group had a significantly higher mean overall seasonal impairment score than the healthy subjects (p

Background Mood disorders require consistent management of symptoms to prevent recurrences of mood episodes. Circadian rhythm (CR) disruption is a key symptom of mood disorders to be proactively managed to prevent mood episode recurrences. This study aims to predict impending mood episodes recurrences using digital phenotypes related to CR obtained from wearable devices and smartphones. Methods The study is a multicenter, nationwide, prospective, observational study with major depressive disorder, bipolar disorder I, and bipolar II disorder. A total of 495 patients were recruited from eight hospitals in South Korea. Patients were followed up for an average of 279.7 days (a total sample of 75 506 days) with wearable devices and smartphones and with clinical interviews conducted every 3 months. Algorithms predicting impending mood episodes were developed with machine learning. Algorithm-predicted mood episodes were then compared to those identified through face-to-face clinical interviews incorporating ecological momentary assessments of daily mood and energy. Results Two hundred seventy mood episodes recurred in 135 subjects during the follow-up period. The prediction accuracies for impending major depressive episodes, manic episodes, and hypomanic episodes for the next 3 days were 90.1, 92.6, and 93.0%, with the area under the curve values of 0.937, 0.957, and 0.963, respectively. Conclusions We predicted the onset of mood episode recurrences exclusively using digital phenotypes. Specifically, phenotypes indicating CR misalignment contributed the most to the prediction of episodes recurrences. Our findings suggest that monitoring of CR using digital devices can be useful in preventing and treating mood disorders.

Although early intervention may help prevent the progression of bipolar disorder, there are some controversies over early pharmacological intervention. In this study, we recruited 40 subjects in the prodromal stage of BD-II (BP), according to bipolar at-risk state criteria. We compared the expression of their plasma proteins with that of 48 BD-II and 75 healthy control (HC) to identify markers that could be detected in a high-risk state. The multiple reaction monitoring method was used to measure target peptide levels with high accuracy. A total of 26 significant peptides were identified through analysis of variance with multiple comparisons, of which 19 were differentially expressed in the BP group when compared to the BD-II and HC groups. Two proteins were overexpressed in the BP group; and were related to pro-inflammation and impaired neurotransmission. The other under-expressed peptides in the BP group were related to blood coagulation, immune reactions, lipid metabolism, and the synaptic plasticity. In this study, significant markers observed in the BP group have been reported in patients with psychiatric disorders. Overall, the results suggest that the pathophysiological changes included in BD-II had already occurred with BP, thus justifying early pharmacological treatment to prevent disease progression.

Aims Antidepressants are common in bipolar disorder (BD), but controversial due to questionable efficacy/tolerability. We assessed baseline antidepressant use/depression associations in BD. Methods Stanford BD Clinic outpatients, enrolled during 2000–2011, assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation, were monitored up to two years with the STEP-BD Clinical Monitoring Form while receiving naturalistic expert treatment. Prevalence/correlates of baseline antidepressant use in recovered (euthymic ≥8 weeks)/depressed patients were assessed. Kaplan–Meier survival analyses assessed times to depressive recurrence/recovery in patients with/without baseline antidepressant use, and Cox Proportional Hazard regression analyses assessed covariate effects. Results Baseline antidepressant use was significantly (albeit without Bonferroni multiple comparison correction) less among 105 recovered (31.4%) versus 153 depressed (44.4%) patients, and among recovered patients (again without Bonferroni correction), associated with Caucasian race, earlier onset, worse Clinical Global Impression scores, and hastened depressive recurrence (only if mood elevation episodes were not censored), driven by lifetime anxiety disorder, and more (even with Bonferroni correction) bipolar II disorder, lifetime anxiety and eating disorders, and core psychotropics. Baseline antidepressant use among depressed patients was associated with significantly (again without Bonferroni correction) older age, female gender, and more (even with Bonferroni correction) anxiolytics/hypnotics, complex pharmacotherapy, and core psychotropics, but no other unfavorable illness characteristic/current mood symptom, and not time to depressive recovery. Limitations Tertiary BD clinic referral sample receiving open naturalistic expert treatment. Analyses without/with Bonferroni correction. Conclusions Additional research is required to assess the complex associations between baseline antidepressant use and longitudinal depressive burden in BD.

The demand for mobile DRAM has increased, with a requirement for high density, high data rates, and low-power consumption to support applications such as 5G communication, multiple cameras, and automotive. Thus, density has increased from 2Gb [1] to 16Gb [2] in LPDDR4 and LPDDR4X, but the maximum density for LPDDR5 is only 12Gb [3] due to the limited package size specification: such as a 496-ball FBGA. In this work, a mosaic architecture is introduced to increase the density to 16Gb, even in a limited package size. Additionally, the I/O performance is improved by shortening the length for the top metal, and a short-feedback sense amplifier (SA) with dedicated VREFs for a 1-tap DFE. The side effect of a mosaic architecture is the performance of the internal DRAM due to a 1.64× long bus line; however, this is mitigated by a fully-source-synchronous (FSS) bus scheme that is robust to PVT variation. In addition, to reduce the power consumption of the long bus line a low-level swing (LLS) scheme is used in low frequency mode. Furthermore, to enhance power efficiency and yield an adaptive-body-bias (ABB) scheme is introduced in a 3rd generation of a 10nm DRAM process.

Background The Seoul Pluripotent Risk for Mental Illness (SPRIM) study was designed to identify predictors leading to mental illness in help-seeking individuals by securing sufficient statistical power through transdiagnostic approaches. The SPRIM study aims to examine the clinical characteristics of high-risk individuals for mental illness and to identify proteomic biomarkers that can predict the onset of mental illness. Methods This paper describes the study protocol of the SPRIM study. We aim to recruit 150 participants who meet the criteria for high risk for major mental illness, 150 patients with major psychiatric disorders (schizophrenia, bipolar disorder, and major depressive disorder), and 50 matched healthy control subjects for 2 years. Clinical evaluations, self-report measures, and proteomic analyses will be implemented. The assessment points are at baseline, 6, 12, 18, and 24 months. Conclusions In the present study, we introduced the study protocol of the SPRIM study, which is the first prospective cohort study of transdiagnostic high-risk concepts using proteomic biomarkers. This study has a paradigm that encompasses various diseases without aiming at predicting and preventing the development of a specific mental illness in help-seeking individuals. The transdiagnostic high-risk concept could be extended to provide a perspective for people with various psychopathological tendencies below a threshold, such that they do not meet the existing diagnostic criteria of mental illnesses, to determine what may lead them to a specific disease and help identify appropriate preventative interventions.

Aims Antidepressant use is controversial in bipolar disorder (BD) due to questionable efficacy/psychiatric tolerability. We assessed demographic/clinical characteristics of baseline antidepressant use in BD patients. Methods Prevalence and correlates of baseline antidepressant use in 503 BD I and BD II outpatients referred to the Stanford Bipolar Clinic during 2000–2011 were assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation. Results Antidepressant use was 39.0%, overall, and was higher in BD II versus BD I (46.9% versus 30.5%, p = 0.0002). Both BD I and BD II antidepressant compared to non-antidepressant users had higher rates of complex pharmacotherapy (≥ 4 mood stabilizers, antipsychotics, and/or antidepressants) and use of other psychotropics. Antidepressant use in BD II versus BD I was higher during euthymia (44.0% vs. 28.0%) and subsyndromal symptoms (56.1% vs. 28.6%), but not depression or mood elevation. Limitations American tertiary BD clinic referral sample receiving open naturalistic treatment. Conclusions In our sample, antidepressant use was higher in BD II versus BD I patients, and was associated with markers of heightened illness severity in both BD I and BD II patients. Additional research is warranted to investigate these complex relationships.

Aims Assess episode accumulation (≥ 10 prior mood episodes) associations with demographic/baseline clinical characteristics and mood episode recurrence/recovery in bipolar disorder (BD). Methods Stanford BD Clinic outpatients enrolled during 2000–2011 were assessed with Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation. Among recovered and syndromal mood episode patients, we assessed episode accumulation associations with demographic/baseline clinical characteristics and with recurrence/recovery (by Kaplan-Meier survival analyses, with mediators assessed with Cox Proportional Hazard Ratio (HR) analyses). Results Among all 450 BD outpatients, almost twice as many had versus lacked episode accumulation (65.8% versus 34.2%), which was less common among 92 recovered versus 193 syndromal mood episode patients (51.1% versus 69.9%). Among recovered patients, episode accumulation was associated with 14/18 (77.7%) demographic/other baseline clinical characteristics, and hastened mood episode recurrence. Among syndromal mood episode patients, episode accumulation was associated with 13/18 (72.2%) demographic/other baseline clinical characteristics, and delayed mood episode recovery. Limitations American tertiary BD clinic referral sample. Conclusion Studies are needed to confirm episode accumulation is associated with hastened mood episode recurrence and delayed mood episode recovery in BD, and to further explore its’ associations with hastened mood elevation recurrence and delayed recovery from depressive and mood elevation episodes, considered separately.

The Mood Disorder Cohort Research Consortium (MDCRC) study is designed as a naturalistic observational prospective cohort study for early-onset mood disorders (major depressive disorders, bipolar disorders type 1 and 2) in South Korea. The study subjects consist of two populations: 1) patients with mood disorders under 25 years old and 2) patients with mood disorders within 2 years of treatment under 35 years old. After successful screening, the subjects are evaluated using baseline assessments and serial follow-up assessments at 3-month intervals. Between the follow-up assessments, subjects are dictated to check their own daily mood status before bedtime using the eMood chart application or a paper mood diary. At the regular visits every 3 months, inter-visit assessments are evaluated based on daily mood charts and interviews with patients. In addition to the daily mood chart, sleep quality, inter-visit major and minor mood episodes, stressful life events, and medical usage pattern with medical expenses are also assessed. Genomic DNA from blood is obtained for genomic analyses. From the MDCRC study, the clinical course, prognosis, and related factors of early-onset mood disorders can be clarified. The MDCRC is also able to facilitate translational research for mood disorders and provide a resource for the convergence study of mood disorders.

Assess bipolar disorder subtype and treatment location effects on bipolar disorder core pharmacotherapy. Outpatients not in a syndromal episode referred to the University of Milan and Stanford University Bipolar Disorder Clinics were assessed with SCID for the fourth Edition of the Diagnostic and Statistical Manual of Mood Disorders, and the Systematic Treatment Enhancement Program for Bipolar Disorder Affective Disorders Evaluation, respectively. Prevalence and clinical correlates of antidepressant, antipsychotic, and mood stabilizer use, in aggregate and individually, were compared in bipolar I (BDI) versus II (BDII) patients in Milan/Stanford and in Milan versus Stanford patients, stratified by subtype. Milan/Stanford pooled BDI versus BDII patients significantly more often took antipsychotic (69.8 versus 44.8%), mood stabilizers (68.6 versus 57.7%), and valproate (40.1 versus 17.5%), and less often took antidepressants (23.1 versus 55.6%) and lamotrigine (9.9 versus 25.2%). Milan versus Stanford patients (stratified by bipolar disorder subtype) significantly more often took antipsychotic (BDI and BDII), antidepressants (BDII), and valproate (BDII), and less often took lamotrigine (BDI). Research regarding bipolar disorder core pharmacotherapy relationships with bipolar subtype and treatment location is warranted to enhance clinical management.

OBJECTIVE The biological rhythm is closely related to mood symptoms. The purpose of this study was to assess the differences in biological rhythms among subjects with mood disorder [bipolar I disorder (BD I), bipolar II disorder (BD II), major depressive disorder (MDD)] and healthy control subjects. METHODS A total of 462 early-onset mood disorder subjects were recruited from nine hospitals. The controls subjects were recruited from the general population of South Korea. Subject groups and control subject were evaluated for the Korean language version of Biological Rhythms Interview of Assessment in Neuropsychiatry (K-BRIAN) at the initial evaluation. RESULTS The mean K-BRIAN scores were 35.59 [standard deviation (SD)=13.37] for BD I, 43.05 (SD=11.85) for BD II, 43.55 (SD=12.22) for MDD, and 29.1 (SD=8.15) for the control group. In the case of mood disorders, biological rhythm disturbances were greater than that in the control group (p

OBJECTIVE Chromosome 22q11 has been implicated as a susceptibility locus of schizophrenia. It also contains various candidate genes for which evidence of association with schizophrenia has been reported. To determine whether genetic variations in chromosome 22q11 are associated with schizophrenia in Koreans, we performed a linkage analysis and case-control association study. METHODS Three microsatellite markers within a region of 4.35 Mb on 22q11 were genotyped for 47 multiplex schizophrenia families, and a non-parametric linkage analysis was applied. The association analysis was done with 227 unrelated patients and 292 normal controls. For 39 single nucleotide polymorphisms (SNPs) spanning a 1.4 Mb region (33 kb interval) containing four candidate schizophrenia genes (DGCR, COMT, PRODH and ZDHHC8), allele frequencies were estimated in pooled DNA samples. RESULTS No significant linkage was found at any of the three microsatellite markers in single and multi-point analyses. Five SNPs showed suggestive evidence of association (p

Aims To assess second-generation antipsychotic (SGA) use, demographics, and clinical correlates in patients with bipolar I disorder (BDI) versus bipolar II disorder (BDII). Methods Stanford Bipolar Disorder (BD) Clinic outpatients enrolled during 2000–2011 were assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation. Current SGA use, demographics, and clinical correlates were assessed for BDI versus BDII. Results Among 503 BD outpatients, in BDI versus BDII, SGA use was more than twice as common (44.0% versus 21.2%), and doses were approximately twice as high. BDI patients taking (N = 107) versus not taking (N = 136) SGAs less often had current full time employment and college degree; and more often had lifetime psychiatric hospitalization, current depression, and current complex pharmacotherapy, and had a higher mean current Clinical Global Impression for Bipolar Version Overall Severity score, and these persisted significantly after covarying for employment and education. Prior psychiatric hospitalization was the most robust correlate of SGA use in BDI patients. In contrast, these demographic and clinical correlates of SGA use were not statistically significant among patients with BDII, although BDII (but not BDI) patients taking (N = 55) versus not taking (N = 205) SGAs were more likely to have current mood stabilizer use (67.3% versus 51.7%). Limitations American tertiary bipolar disorder clinic referral sample, cross-sectional design. Conclusions Current SGA use was robustly associated with prior psychiatric hospitalization in BDI and to a more limited extent with current mood stabilizer use in BDII. SGA use associations with other unfavorable illness characteristics in BDI were less robust.

Aims To assess differential relationships between lifetime anxiety disorder/current anxiety symptoms and longitudinal depressive severity in bipolar disorder (BD). Methods Stanford BD Clinic outpatients enrolled during 2000–2011 were assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation and followed with the STEP-BD Clinical Monitoring Form while receiving naturalistic treatment for up to two years. Baseline unfavorable illness characteristics/current mood symptoms and times to depressive recurrence/recovery were compared in patients with versus without lifetime anxiety disorder/current anxiety symptoms. Results Among 105 currently recovered patients, lifetime anxiety disorder was significantly associated with 10/27 (37.0%) demographic/other unfavorable illness characteristics/current mood symptoms/current psychotropics, hastened depressive recurrence (driven by earlier onset age), and a significantly (> two-fold) higher Kaplan-Meier estimated depressive recurrence rate, whereas current anxiety symptoms were significantly associated with 10/27 (37.0%) demographic/other unfavorable illness characteristics/current mood symptoms/current psychotropics and hastened depressive recurrence (driven by lifetime anxiety disorder), but only a numerically higher Kaplan-Meier estimated depressive recurrence rate. In contrast, among 153 currently depressed patients, lifetime anxiety disorder/current anxiety symptoms were not significantly associated with time to depressive recovery or depressive recovery rate. Limitations American tertiary BD clinic referral sample, open naturalistic treatment. Conclusions Research is needed regarding differential relationships between lifetime anxiety disorder and current anxiety symptoms and hastened/delayed depressive recurrence/recovery – specifically whether lifetime anxiety disorder versus current anxiety symptoms has marginally more robust association with hastened depressive recurrence, and whether both have marginally more robust associations with hastened depressive recurrence versus delayed depressive recovery, and related clinical implications.

Carl von Ossietzky Universit¨at Oldenburg, Institut fur¨ Physik, 26111 Oldenburg, Germany(Received 20 January 2010)A low-temperature near-field scanning optical microscope (LT-NSOM) is designed and realized inorder to study the optical properties of nanostructures at cryogenic temperatures in the UV-visiblewavelength range. Due to the simple and extensive optical design, any type of NSOM operationmode is accessible. In particular, the localized photoluminescence spectra of nanostructures can bemeasured at temperatures from 13 K up to 300 K. We successfully demonstrate the performance ofour LT-NSOM by investigating InGaN/GaN multiple quantum wells grown on a sapphire substrateat 15 K.

We report on terahertz focusing through rectangular slit apertures on thin metal film by using terahertz time domain spectroscopy both in the farand in the near-field. Our experiments show that far-field perfect transmission is maintained in the rectangular slit array even as the aperture coverage decreases. Near-field imaging supports the field enhancement in the single rectangular aperture indeed occurring at a frequency equal to the fundamental shape resonance frequency.

Chromosome 1q contains a few loci for which modest evidence of linkage with schizophrenia has been reported in several independent studies. However, markers showing the peak linkage signal are dispersed over a large chromosomal region. In addition, inconsistent findings have been generated from different populations or different subgroups of the same populations. The purpose of the current study is to determine whether those loci are linked to schizophrenia in the Korean population. We investigated 46 Korean multiplex schizophrenia families, initially using 11 microsatellite markers spanning around 91 cM region of 1p22∼42. In a non-parametric linkage analysis, D1S249 located on 1q32.1 showed statistical evidence suggestive of linkage. At the second stage analysis for narrowing down the region, four additional nearby markers were genotyped. In the single point analysis, we found another suggestive linkage signal at D1S2891. The highest NPL score of 2.67 (P = 0.0039) was obtained in the multi-point analysis. This study provides supportive evidence for linkage of chromosome 1q32 with schizophrenia. © 2006 Wiley-Liss, Inc.

Growth of large-scale patterned, wrinkle-free graphene and the gentle transfer technique without further damage are most important requirements for the practical use of graphene. Here we report the growth of wrinkle-free, strictly uniform monolayer graphene films by chemical vapor deposition on a platinum (Pt) substrate with texture-controlled giant grains and the thermal-assisted transfer of large-scale patterned graphene onto arbitrary substrates. The designed Pt surfaces with limited numbers of grain boundaries and improved surface perfectness as well as small thermal expansion coefficient difference to graphene provide a venue for uniform growth of monolayer graphene with wrinkle-free characteristic. The thermal-assisted transfer technique allows the complete transfer of large-scale patterned graphene films onto arbitrary substrates without any ripples, tears, or folds. The transferred graphene shows high crystalline quality with an average carrier mobility of ∼ 5500 cm(2) V(-1) s(-1) at room temperature. Furthermore, this transfer technique shows a high tolerance to variations in types and morphologies of underlying substrates.

Pt thin films of various thicknesses (30 nm ∼ 200 nm) were deposited on Si wafers with SiO2, Ti, TiO2, or IrO2 buffer layers at various temperatures (room temperature ∼200 °C) by a direct current magnetron sputtering process. The Pt films showed a strong (111)-preferred texture irrespective of the thickness, under-layer, and growth temperature. The authors previously reported [J-E. Lim, D-Y. Park, J.K. Jeong, G. Darlinski, H.J. Kim, and C.S. Hwang, Appl. Phys. Lett. 81, 3224 (2002)] that the films were composed of three kinds of grains with slightly different (111) lattice parameters (bulklike, 1.0% and 2.1% larger). This study details the microstructural variations of the Pt films according to the variations of experimental parameters. The different deposition conditions produced slightly different crystalline structures, but the three different (111) lattice parameters were always found. Epitaxial (200) Pt films on a (200) MgO substrate and a highly (111) textured Au thin film on a SiO2/Si did not show the same splitting in the lattice parameter. The grains with 1.0% and 2.1% larger (111) lattice parameter almost disappeared after postannealing at 1000 °C. However, surface chemical binding of the Pt film before and after annealing was unchanged. Therefore, it is believed that the lattice parameter splitting in the (111) textured Pt film originated from the interfacial grains with the distorted crystal structure due probably to growth stress.

The pyroelectric and dielectric properties of Pb(Zr0.3,Ti0.7)O3 (PZT) thin films are systematically investigated as functions of film thickness ranging from 0.3 to 1 µm. For better detectivity of the film, high pyroelectric coefficient, low dielectric coefficient and loss tangent are needed. It can be achieved by highly textured (111) preferred orientation and dense microstructure. To minimize the unwanted preferred orientation with increasing film thickness, a step-by-step annealing process and highly textured (111) Pt bottom electrodes are applied. With increasing film thickness, the squareness of polarization hysteresis loops and remanent polarization values are maximized. Although there is a slight variation of preferred orientation with film thickness, dielectric properties are markedly changed due to microstructural variation. Because of the large improvement of loss tangent, the figure of merit is improved with film thickness. It is maximized at a thickness of 1 µm. The maximum pyroelectric coefficient measured by the Byer-Roundy method is 38 nC/cm2K.

The effects of the microstructure of a platinum bottom electrode on the oxidation behavior of a TiN diffusion barrier layer were investigated. The microstructures of the bottom Pt electrodes were varied from a columnar structure to a granular one by adding oxygen to the sputtering gas during the sputter-deposition and subsequent vacuum annealing process. It was found that a Pt film with a granular microstructure significantly retarded the oxidation of the underlying TiN barrier layer during annealing at 650°C for 30 min in air. However, the Pt film with a conventional columnar microstructure was unable protect the TiN layer from oxidation at temperatures as low as 450°C. The improved oxidation resistance of the barrier layer, as a result of modifying the microstructure of Pt films, is expected to contribute to the implementation of high-dielectric and ferroelectric capacitors into high-density memory devices.

The solely orientation-related effects on ferroelectric and piezoelectric properties of Pb(Zr0.3,Ti0.7)O3 (PZT) thin films with identical processing conditions were investigated using near lattice matched Pt electrodes, that is, (111)-textured Pt for (111)-oriented PZT thin films and (100)-textured Pt for (100)-oriented films. As a result, the film composition, microstructure, and topography were highly similar in all cases. (111)-oriented tetragonal PZT films exhibited highly rectangular P–V hysteresis loops with a slightly better fatigue endurance than the (100)-oriented films. However, the measured d33 values of (100)-oriented PZT films were somewhat higher than those of (111)-oriented films, indicating a consistency with C–V curves. It was shown that in tetragonal symmetry, the intrinsic effect was largest in the piezoelectricity of PZT thin films.

The effects of IrO2/Pt layered hybrid bottom and/or top electrode structures on the leakage current density versus voltage (J–V), polarization versus voltage (P–V), ferroelectric imprint, and fatigue properties of chemical-solution-derived Pb(ZrxTi1−x)O3 (PZT, Zr/Ti = 35/65) thin films were investigated. The best P–V and J–V performances were obtained from a capacitor with nonhybrid electrodes (Pt/PZT/Pt capacitor). However, the poor fatigue performance of the capacitor required the adoption of hybrid electrode structures. A thin IrO2 layer, as thin as 6 nm, which was inserted between top Pt electrode and PZT layer was sufficient for improving the fatigue performance without any degradation of the other ferroelectric properties. However, the same layer adopted on the bottom Pt electrode was not effective in improving the fatigue performance with degradation in P–V and J–V properties. This was ascribed to IrO2 layer dissolution into the PZT layer during the crystallization annealing of the PZT thin film. A thicker IrO2 layer resulted in more serious degradation.

The effect of the Pt electrode and the Pt-IrO₂ hybrid electrode on the performance of ferroelectric device was investigated. The modified Pt thin films with non-columnar structure significantly reduced the oxidation of TiN diffusion barrier layer, which rendered it possible to incorporate the simple stacked structure of Pt/TiN/poly-Si plug. When a Pt-IrO₂ hybrid electrode is applied, PZT thin film properties are influenced by the thickness and the partial coverage of the electrode layers. The optimized Pt-IrO₂ hybrid electrode significantly enhanced the fatigue properties with minimal leakage current.

The improvement in switching performance of ferroelectric Pb(ZrxTi1-x)O3 (PZT) thin film capacitors under a lower applied voltage was investigated. PZT thin films were prepared by a chemical-solution-deposition method. The film thickness decrease was not as effective as expected due to the increased coercive field. Decreases in film thickness also resulted in a substantial increase in leakage current at the operation voltage. The stacked layer of the tetragonal and rhombohedral PZT thin films slightly improved the low voltage saturation behavior of the remanent polarization (Pr). Cation impurities, such as La, Ca and Sr, also assisted in improving the saturation behavior. However, a modification of the stock solution by adding a special chelating agent, which also greatly improved the shelf life of the solution, was the most effective method of improving Pr saturation of the undoped tetragonal PZT film. A 85% Pr saturation was obtained at an applied voltage as low as 1.5 V when the PZT film thick...

(200)-oriented Pt thin films were deposited on SiO2/Si substrates by dc magnetron sputtering using Ar/O2 gas mixtures. Oxygen incorporation into Pt films changed deposition rate, resistivity, stress, and preferred orientation of the films. Increase in film resistivity and decrease in tensile stress were presumed to be the results of the incorporated oxygen into grain boundaries, while the change of preferred orientation resulted from the oxygen incorporation into the Pt lattice. The preferential growth of (200) planes with less total strain energy from the incorporated oxygen resulted in strong (200) preferred orientation in Pt films.

Highly (200)-oriented Pt films on SiO2/Si substrates were successfully prepared by a combination of a dc magnetron sputtering using Ar/O2 gas mixtures and subsequent controlled annealing. The intensity ratio of (200) to (111) planes (I200/I111) was over 200. The (200)-oriented Pt microcrystallites were less susceptible to amorphization due to their lower strain energy with oxygen incorporation than (111)-oriented ones. The controlled grain growth from the selected (200)-oriented seed microcrystallites during subsequent annealing provided a kinetic pathway where grain growth of the seed microcrystallites was predominant, while suppressing the nucleation of surface energy-driven, (111)-oriented seed microcrystallites and subsequent (111) preferred orientation.

Lead oxide thin films were deposited on Ir/IrO 2 /SiO 2 /Si substrates by liquid delivery metalorganic chemical vapor deposition at 525 °C in order to understand its influence on Pb-based ferroelectric film growth. The Ir substrates were variously pretreated in situ to control the surface oxidation state. Fully oxidized lead oxide films were grown on a nonoxidized Ir or fully oxidized IrO 2 surface. The lead oxide film growth on partially oxidized IrO x (x < 2) was hampered resulting in metallic Pb incorporation which may largely degrade the electrical properties of the film. IrO x oxidizes quickly consuming the supplied oxygen.

Symptom dimensions of schizophrenia are likely to be the intermediate phenotypes under the control of disease-susceptibility genes, or separate traits related to disease-modifier genes. This study aimed to identify chromosomal loci linked to symptom dimensions of schizophrenia through genome-wide quantitative trait locus (QTL) linkage analysis. The study subjects consisted of 56 families with 183 members including 123 affected individuals. Symptom evaluations were performed on lifetime basis. Through principal component factor analysis, eight quantitative phenotypes representing symptom dimensions were identified. Genotyping was done for 6008 SNP markers, and genome-wide QTL linkage analysis was performed. No symptom dimension showed a significant linkage attaining genome-wide empirical thresholds. We observed seven regions yielding linkage signals attaining genome-wide empirical thresholds for suggestive linkage (NPL Z score=2.78–3.49); chromosome 15q26.1 for ‘non-paranoid delusion factor', 2p24.3 and 7q31.1 for ‘prodromal impairment factor', 1q32.1, 9p21.3, and 9q31.2 for ‘negative symptom factor', and 10p13 for ‘disorganization factor'. Among these loci, chromosome 2p24.3 and 1q32.1 overlap with susceptibility loci of schizophrenia identified in our previous linkage studies. This study suggests the existence of genetic loci related to various clinical features of schizophrenia. Further genetic analyses for these dimensional phenotypes are warranted.

Pb(Zr,Ti)O3 (PZT) thin films were deposited on Pt/Ti and Pt/IrO2 electrode stacks with various Pt thicknesses (30–200 nm) by a sol–gel process. The sputter-deposited Pt films showed a (111)-preferred texture irrespective of the thickness. However, a high-resolution x-ray diffraction study of the Pt films showed that the films were composed of three kinds of grains with slightly different lattice parameters. The grains with a bulk-like lattice parameter grew with increasing Pt thickness, which was accompanied with an improvement in the crystalline quality. Accordingly, the crystallization and ferroelectric behavior of the 100-nm-thick PZT films improved with increasing Pt film thickness. However, the PZT films on the Pt/IrO2 electrode showed a deteriorated ferroelectric performance due to the outward diffusion of the Ir (O) onto the Pt surface, which increases the depolarizing field and amount of charge injection by the formation of a conducting phase.

Background The present study was designed to investigate whether bipolar II disorder (BP-II) has different characteristics from bipolar I disorder (BP-I), not only in manic severity but also in clinical features, prior course, comorbidity, and family history, sufficiently enough to provide its nosological separation from BP-I. Methods Comprehensive clinical evaluation was performed based on information available from ordinary clinical settings. Seventy-one BP-I and 34 BP-II patients were assessed using the Diagnostic Interview for Genetic Studies, Korean version. Psychiatric assessment for first-degree relatives ( n = 374) of the probands was performed using the modified version of the Family History-Research Diagnostic Criteria. Results The frequency of depressive episodes was higher in BP-II ( p = 0.009) compared to BP-I. Further, seasonality ( p = 0.035) and rapid-cycling course ( p = 0.062) were more common in BP-II. Regarding manic expression, ‘elated mood’ was predominant in BP-II whereas ‘elated mood’ and ‘irritable mood’ were equally prevalent in BP-I. With regard to depressive symptoms, psychomotor agitation, guilty feeling, and suicidal ideation were more frequently observed in BP-II. BP-II patients exhibited a higher trend of lifetime co-occurrence of an axis I diagnosis ( p = 0.09), and a significantly higher incidence of phobia and eating disorder. The overall occurrence rate of psychiatric illness in first-degree relatives was 15.4% in BP-I and 26.5% in BP-II ( p = 0.01). Major depression ( p = 0.005) and substance-related disorder ( p = 0.051) were more prevalent in relatives of BP-II probands. Conclusion Distinctive characteristics of BP-II were identified in the current study and could be adopted to facilitate the differential diagnosis of BP-I and BP-II in ordinary clinical settings.

We report huge field accumulations in rectangular aperture arrays on thin metal film by using shape resonance in THz frequency region. A large far-field transmittance enhancement is observed in the samples of various widths ranging from 10 μm to 1.8 μm which corresponds to only an order of λ/100. Theoretical calculations based on vector diffraction theory indicates 230 times field enhancement in the near-field for the 1.8 μm rectangular aperture.

The present study reports the results of a genome-wide SNP linkage scan for schizophrenia in the Korean population. Fifty-six multiplex schizophrenia families were analyzed. Clinical evaluations on all subjects were consistently performed by raters in a single research team. Multipoint non-parametric linkage analysis was performed, and empirical simulations were generated to determine genome-wide significance. The authors found genome-widely significant evidence of linkage for schizophrenia to chromosomes 2p24.3 (NPL Z = 3.18) and 6q27 (NPL Z = 2.90). Six other chromosomal regions, that is, 3q24, 13q12.3, 18q22.3, 20p12.2, 4p14, and 1p36.12, yielded NPL Z scores of above 2.0 for either broad or narrow phenotype classes. Although linkage to these loci has not received prominent attention in studies on Caucasian families, multiple overlaps were observed between our loci (on 2p, 3q, and 13q) and linkage peaks generated from extended families in various isolated populations. Fine mappings and the detection of candidate genes within these regions are warranted.

We report on a near-field amplification in a transmission metallic grating, whereby the spatially and spectrally resolved near-field intensity reaches {approx}20 times the incident intensity at the surface plasmon polariton resonance. The amplified value is maintained up to {approx}2 {mu}m away from the surface. Our experiments show that the near-field amplification in the transmission grating, which is strongly implied in a recent superlens design, indeed occurs at the surface plasmon polariton resonance. Theoretical calculation shows good agreement with experiment and also reveals that the horizontal magnetic field is predominantly amplified. Our results suggest that a grating-assisted superlens should have its optimal functional wavelength right around the surface plasmon resonance.

We report on spatially and spectrally resolved near-field Fresnel transmission coefficients in metallic nano-slit arrays using broadband femtosecond laser. The peak value of Fresnel coefficient is observed at the wavelength near surface plasmon polariton resonance where the spatially resolved Fresnel coefficient shows a good standing wave pattern.