23 resultados para Bipolar transistors


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Repetitive transcranial magnetic stimulation (rTMS) has been widely tested and shown to be effective for unipolar depression. Although it has also been investigated for bipolar depression (BD), there are only few rTMS studies with BD. Here, we investigated 56 patients with BD who received rTMS treatment until remission (defined as Hamilton Depression Rating Scores <= 7). We used simple and multiple logistic regressions to identify clinical and demographic predictors associated with duration of treatment (defined as <15 vs. >15 rTMS sessions). Age, refractoriness, number of prior depressive episodes, and severe depression at baseline were associated with a longer rTMS treatment. In the multivariate analysis, refractoriness (likelihood ratio (LR) = 4.33; p < 0.01) and baseline severity (LR = 0.18, p < 0.01) remained significant predictors. Our preliminary study showed that, in remitted patients, refractoriness and severity of index episode are associated with the need of a longer rTMS treatment; providing preliminary evidence of important factors associated with rTMS parameters adjustment.

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V393 Scorpii is a double periodic variable characterized by a relatively stable non-orbital photometric cycle of 253 d. Mennickent et al. argue for the presence of a massive optically thick disc around the more massive B-type component and describe the evolutionary stage of the system. In this paper, we analyse the behaviour of the main spectroscopic optical lines during the long non-orbital photometric cycle. We study the radial velocity of the donor determining its orbital elements and find a small but significant orbital eccentricity (e = 0.04). The donor spectral features are modelled and removed from the spectrum at every observing epoch using the light-curve model given by Mennickent et al. We find that the line emission is larger during eclipses and mostly comes from a bipolar wind. We also find that the long cycle is explained in terms of a modulation of the wind strength; the wind has a larger line and continuum emissivity at the high state. We report the discovery of highly variable chromospheric emission in the donor, as revealed by the Doppler maps of the emission lines Mg II 4481 and C I 6588. We discuss notable and some novel spectroscopic features like discrete absorption components, especially visible at blue depressed O I 7773 absorption wings during the second half-cycle, Balmer double emission with V/R curves showing 'Z-type' and 'S-type' excursions around secondary and main eclipses, respectively, and H beta emission wings extending up to +/- 2000 km s(-1). We also discuss possible causes for these phenomena and for their modulations with the long cycle.

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This paper proposes a drain current model for triple-gate n-type junctionless nanowire transistors. The model is based on the solution of the Poisson equation. First, the 2-D Poisson equation is used to obtain the effective surface potential for long-channel devices, which is used to calculate the charge density along the channel and the drain current. The solution of the 3-D Laplace equation is added to the 2-D model in order to account for the short-channel effects. The proposed model is validated using 3-D TCAD simulations where the drain current and its derivatives, the potential, and the charge density have been compared, showing a good agreement for all parameters. Experimental data of short- channel devices down to 30 nm at different temperatures have been also used to validate the model.

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There is growing evidence that the course of Bipolar Affective Disorder (BAD) can be altered by psychotherapeutic approaches, such as Psychoeducation. Therefore, this study was performed with the objective of identifying the implications of a Psychoeducation group on the everyday lives of individuals with BAD. To do this, the authors chose to perform a qualitative case study. Participants included twelve individuals with BAD who had attended at least six meetings of the Psychoeducation Group held at the Sao Jose do Rio Preto Faculty of Medicine (FAMERP). Semi-structured interviews were performed, which were recorded and then transcribed and subjected to Thematic Analysis. The present study showed that the referred group experience promoted the individuals' knowledge acquisition; their awareness regarding the disease and adherence to treatment; their making positive changes in life; the possibility of helping other patients to benefit from the knowledge learned in the group; and their awareness regarding other realities and coping strategies, obtained by exchanging experiences with other participants.

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Background: The expression 'bipolar disorder' refers to any of several psychological disorders of mood that alternate episodes of depression and mania. Also called manic depression or manic-depressive illness, it is a relatively common but unknown pathology that brings some stigmas for patients and provokes deleterious effects for their lives. This research aimed to comprehend actions, behaviors and emotions involved with bipolar disorder, through narratives of patient's personal and familiar histories. Methods: We surveyed 30 patients from a psychiatric service located in Aparecida, Paraiba, Brazil. Selected patients had bipolar disorder according to DSM-IV. For data collection, we used non-structured interview, approaching specific aspects related to bipolar disorder. Quantitative and qualitative analysis were done and Hamilton Rating Scale for Depression (HAMD) was used. Results: Most of patients presented depressive actions associated with moderate euphoria. 11 of them related familiar history of psychopathology. Mania and hippomania were prevalent on male gender, while psychotic symptoms overlay ate female. Conclusion: Patients lack a translation of behavioral and temperamental processes to minimize harm caused to their lives.

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Purpose - The purpose of this paper is to develop an efficient numerical algorithm for the self-consistent solution of Schrodinger and Poisson equations in one-dimensional systems. The goal is to compute the charge-control and capacitance-voltage characteristics of quantum wire transistors. Design/methodology/approach - The paper presents a numerical formulation employing a non-uniform finite difference discretization scheme, in which the wavefunctions and electronic energy levels are obtained by solving the Schrodinger equation through the split-operator method while a relaxation method in the FTCS scheme ("Forward Time Centered Space") is used to solve the two-dimensional Poisson equation. Findings - The numerical model is validated by taking previously published results as a benchmark and then applying them to yield the charge-control characteristics and the capacitance-voltage relationship for a split-gate quantum wire device. Originality/value - The paper helps to fulfill the need for C-V models of quantum wire device. To do so, the authors implemented a straightforward calculation method for the two-dimensional electronic carrier density n(x,y). The formulation reduces the computational procedure to a much simpler problem, similar to the one-dimensional quantization case, significantly diminishing running time.

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Background: One of the many cognitive deficits reported in bipolar disorder (BD) patients is facial emotion recognition (FER), which has recently been associated with dopaminergic catabolism. Catechol-O-methyltransferase (COMT) is one of the main enzymes involved in the metabolic degradation of dopamine (DA) in the prefrontal cortex (PFC). The COMT gene polymorphism rs4680 (Val(158)Met) Met allele is associated with decreased activity of this enzyme in healthy controls. The objective of this study was to evaluate the influence of Val(158)Met on FER during manic and depressive episodes in BD patients and in healthy controls. Materials and methods: 64 BD type I patients (39 in manic and 25 in depressive episodes) and 75 healthy controls were genotyped for COMT rs4680 and assessed for FER using the Ekman 60 Faces (EK60) and Emotion Hexagon (Hx) tests. Results: Bipolar manic patients carrying the Met allele recognized fewer surprised faces, while depressed patients with the Met allele recognized fewer "angry" and "happy" faces. Healthy homozygous subjects with the Met allele had higher FER scores on the Hx total score, as well as on "disgust" and "angry" faces than other genotypes. Conclusion: This is the first study suggesting that COMT rs4680 modulates FER differently during BD episodes and in healthy controls. This provides evidence that PFC DA is part of the neurobiological mechanisms of social cognition. Further studies on other COMT polymorphisms that include euthymic BD patients are warranted. ClinicalTrials.gov Identifier: NCT00969. (C) 2011 Elsevier B.V. All rights reserved.

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Introduction: Compulsive buying (CB) is currently classified as an impulse control disorder (ICD) not otherwise classified. Compulsive buying prevalence is estimated at around 5% of the general population. There is controversy about whether CB should be classified as an ICD, a subsyndromal bipolar disorder (BD), or an obsessive-compulsive disorder (OCD) akin to a hoarding syndrome. To further investigate the appropriate classification of CB, we compared patients with CB, BD, and OCD for impulsivity, affective instability, hoarding, and other OCD symptoms. Method: Eighty outpatients (24 CB, 21 BD, and 35 OCD) who were neither manic nor hypomanic were asked to fill out self-report questionnaires. Results: Compulsive buying patients scored significantly higher on all impulsivity measures and on acquisition but not on the hoarding subdimensions of clutter and "difficulty discarding." Patients with BD scored higher on the mania dimension from the Structured Clinical Interview for Mood Spectrum scale. Patients with OCD scored higher on obsessive-compulsive symptoms and, particularly, higher on the contamination/washing and checking dimensions from the Padua Inventory; however, they did not score higher on any hoarding dimension. A discriminant model built with these variables correctly classified patients with CB (79%), BD (71%), and OCD (77%). Conclusion: Patients with CB came out as impulsive acquirers, resembling ICD- rather than BD- or OCD-related disorders. Manic symptoms were distinctive of patients with BD. Hoarding symptoms other than acquisition were not particularly associated with any diagnostic group. (C) 2012 Elsevier Inc. All rights reserved.

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Bauer M, Glenn T, Alda M, Andreassen OA, Ardau R, Bellivier F, Berk M, Bjella TD, Bossini L, Del Zompo M, Dodd S, Fagiolini A, Frye MA, Gonzalez-Pinto A, Henry C, Kapczinski F, Kliwicki S, Konig B, Kunz M, Lafer B, Lopez-Jaramillo C, Manchia M, Marsh W, Martinez-Cengotitabengoa M, Melle I, Morken G, Munoz R, Nery FG, ODonovan C, Pfennig A, Quiroz D, Rasgon N, Reif A, Rybakowski J, Sagduyu K, Simhandl C, Torrent C, Vieta E, Zetin M, Whybrow PC. Impact of sunlight on the age of onset of bipolar disorder. Bipolar Disord 2012: 14: 654663. (c) 2012 The Authors. Journal compilation (c) 2012 John Wiley & Sons A/S. Objective: Although bipolar disorder has high heritability, the onset occurs during several decades of life, suggesting that social and environmental factors may have considerable influence on disease onset. This study examined the association between the age of onset and sunlight at the location of onset. Method: Data were obtained from 2414 patients with a diagnosis of bipolar I disorder, according to DSM-IV criteria. Data were collected at 24 sites in 13 countries spanning latitudes 6.3 to 63.4 degrees from the equator, including data from both hemispheres. The age of onset and location of onset were obtained retrospectively, from patient records and/or direct interviews. Solar insolation data, or the amount of electromagnetic energy striking the surface of the earth, were obtained from the NASA Surface Meteorology and Solar Energy (SSE) database for each location of onset. Results: The larger the maximum monthly increase in solar insolation at the location of onset, the younger the age of onset (coefficient= -4.724, 95% CI: -8.124 to -1.323, p = 0.006), controlling for each countrys median age. The maximum monthly increase in solar insolation occurred in springtime. No relationships were found between the age of onset and latitude, yearly total solar insolation, and the maximum monthly decrease in solar insolation. The largest maximum monthly increases in solar insolation occurred in diverse environments, including Norway, arid areas in California, and Chile. Conclusion: The large maximum monthly increase in sunlight in springtime may have an important influence on the onset of bipolar disorder.

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Background: Recent evidence suggests an association between migraine and bipolar disorder (BD), although the impact of this association in the clinical course of BD is relatively unknown. Objective: This study aimed to compare 2 groups of individuals with BD (with vs without comorbid migraine) and evaluate differences in severity of clinical course. Methods: Three hundred thirty-nine adults with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition defined bipolar or II disorder were enrolled and divided into 2 groups: with and without comorbid migraine. Demographic and clinical data were obtained using standardized interviews. Results: Patients with comorbid migraines had more mood episodes, especially those with depressive polarity. In addition, comorbid migraine was associated with a higher prevalence of psychiatric and general medical comorbidities. Differences between the 2 groups in number of lifetime hospitalizations for depression/mania, rates of rapid cycling, and history of suicide attempts were not observed after Bonferroni correction. Conclusions: Comorbid migraine seems to be associated with poor outcomes in BD. Additional studies should be conducted to investigate shared vulnerabilities and pathophysiologic mechanisms as well as treatment optimization of both illnesses. (C) 2012 Elsevier Inc. All rights reserved.

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Introduction: Bipolar disorder (BD) is a highly incapacitating disease typically associated with high rates of familial dysfunction. Despite recent literature suggesting that maternal care is an important environmental factor in the development of behavioral disorders, it is unclear how much maternal care is dysfunctional in BD subjects. Objective: The objective of this study was to characterize maternal care in DSM-IV/SCID diagnosed BD type I subjects compared to healthy controls with (PD) and without (NPD) other psychiatric diagnoses. Materials and methods: Thirty-four BD mothers and 106 controls underwent an interview about family planning and maternal care, obstetrical complications, and mother-child interactions. K-SADS-PL questions about violence exposure were used to ascertain domestic violence and physical/sexual abuse. Results: BD mothers were less likely to have stable unions (45.5%; p < 0.01) or to live with the biological father of their children (33.3%; p < 0.01), but had higher educational level and higher rates of social security use/retirement. They also had fewer children and used less contraceptive methods than controls. Children of BD women had higher rates of neonatal anoxia, and reported more physical abuse (16.1%; p = 0.02) than offspring of NPD mothers. Due to BD mothers' symptoms, 33.3% of offspring suffered physical and/or psychological abuse. Limitations: Post hoc analysis, and the use of questions as a surrogate of symptoms as opposed to validated instruments. Conclusion: This is one of few reports confirming that maternal care given by BD women is dysfunctional. BD psychopathology can lead to poor maternal care and both should be considered important environmental risk factors in BD, suggesting that BD psychoeducation should include maternal care orientation. (C) 2012 Elsevier B.V. All rights reserved.

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Introduction: Impairments in facial emotion recognition (PER) have been reported in bipolar disorder (BD) during all mood states. FER has been the focus of functional magnetic resonance imaging studies evaluating differential activation of limbic regions. Recently, the alpha 1-C subunit of the L-type voltage-gated calcium channel (CACNA1C) gene has been described as a risk gene for BD and its Met allele found to increase CACNA1C mRNA expression. In healthy controls, the CACNA1C risk (Met) allele has been reported to increase limbic system activation during emotional stimuli and also to impact on cognitive function. The aim of this study was to investigate the impact of CACNA1C genotype on FER scores and limbic system morphology in subjects with BD and healthy controls. Material and methods: Thirty-nine euthymic BD I subjects and 40 healthy controls were submitted to a PER recognition test battery and genotyped for CACNA1C. Subjects were also examined with a 3D 3-Tesla structural imaging protocol. Results: The CACNA1C risk allele for BD was associated to FER impairment in BD, while in controls nothing was observed. The CACNA1C genotype did not impact on amygdala or hippocampus volume neither in BD nor controls. Limitations: Sample size. Conclusion: The present findings suggest that a polymorphism in calcium channels interferes FER phenotype exclusively in BD and doesn't interfere on limbic structures morphology. (C) 2012 Elsevier B.V. All rights reserved.

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Background: The association between suicidal behavior and quality of life (QoL) in bipolar disorder (BD) is poorly understood. Worse QoL has been associated with suicide attempts and suicidal ideation in schizophrenic patients, but this relationship has not been investigated in BD. This study tested whether a history of suicide attempts was associated with poor QoL in a well-characterized sample of patients with BD, as has been observed in other psychiatric disorders and in the general population. Methods: One hundred eight patients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition BD type I (44 with previous suicide attempts, 64 without previous suicide attempts) were studied. Quality of life was assessed using the World Health Organization's Quality of Life Instrument Short Version. Depressive and manic symptoms were assessed using the Hamilton Depression Rating Scale-17 items and the Young Mania Rating Scale. Results: Patients with BD and previous suicide attempts had significantly lower scores in all the 4 domains of the World Health Organization's Quality of Life Instrument Short Version scale than did patients with BD but no previous suicide attempts (physical domain P=.001; psychological domain P <.0001; social domain P=.001, and environmental domain P=.039). In the euthymic subgroup (n=70), patients with previous suicide attempts had significantly lower scores only in the psychological and social domains (P=.020 and P=.004). Limitations: This was a cross-sectional study, and no causal associations can be assumed. Conclusions: Patients with BD and a history of previous suicide attempts seem to have a worse QoL than did patients who never attempted suicide. Poorer QoL might be a marker of poor copying skills and inadequate social support and be a risk factor for suicidal behavior in BD. Alternatively, poorer QoL and suicidal behavior might be different expressions of more severe BD. (C) 2012 Elsevier Inc. All rights reserved.

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Neuroimaging studies suggest anterior-limbic structural brain abnormalities in patients with bipolar disorder (BD), but few studies have shown these abnormalities in unaffected but genetically liable family members. In this study, we report morphometric correlates of genetic risk for BD using voxel-based morphometry. In 35 BD type I (BD-I) patients, 20 unaffected first-degree relatives (UAR) of BD patients and 40 healthy control subjects underwent 3 T magnetic resonance scanner imaging. Preprocessing of images used DARTEL (diffeomorphic anatomical registration through exponentiated lie algebra) for voxel-based morphometry in SPM8 (Wellcome Department of Imaging Neuroscience, London, UK). The whole-brain analysis revealed that the gray matter (GM) volumes of the left anterior insula and right inferior frontal gyrus showed a significant main effect of diagnosis. Multiple comparison analysis showed that the BD-I patients and the UAR subjects had smaller left anterior insular GM volumes compared with the healthy subjects, the BD-I patients had smaller right inferior frontal gyrus compared with the healthy subjects. For white matter (WM) volumes, there was a significant main effect of diagnosis for medial frontal gyrus. The UAR subjects had smaller right medial frontal WM volumes compared with the healthy subjects. These findings suggest that morphometric brain abnormalities of the anterior-limbic neural substrate are associated with family history of BD, which may give insight into the pathophysiology of BD, and be a potential candidate as a morphological endophenotype of BD. Molecular Psychiatry (2012) 17, 412-420; doi: 10.1038/mp.2011.3; published online 15 February 2011

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This Letter presents an analysis of the zero temperature coefficient (ZTC) bias in junctionless nanowire transistors (JNTs). Unlike in previous works, which had shown that JNT did not present a ZTC point, this work shows that ZTC may occur in JNTs depending mainly on the series resistance of the devices and its dependence on the temperature. Experimental results of drain current, threshold voltage, and series resistance are presented for both long and short channel n and p-type devices. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4744965]