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Verdolini, Norma. "Self and Hetero-Aggression: Clinical Implications in Bipolar Disorder and Mixed States." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/665442.
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The poorest outcomes in bipolar disorder are represented by self-aggressive (i.e. deliberate self-harm, attempted or completed suicide) and hetero-aggressive violent behaviors. A better understanding of the clinical factors associated with both the risk of criminal behavior and the risk of self-injurious behaviors among individuals suffering from bipolar disorder may improve the course of illness and the risk management. The main objective of this doctoral thesis was to evaluate the psychiatric correlates of self- or hetero-aggression in the context of bipolar disorder, particularly in those patients presenting mixed features. The five published articles included in this thesis had different study designs: Study I. A meta-analysis including studies on the association between bipolar disorder and violent criminal behaviors; Study II. A cross-sectional study assessing clinical correlates of deliberate self-harm and suicide attempts in prisoners, particularly mood disorders and bipolar disorder; Study III. A post-hoc analysis of the Bipolar Disorders: Improving Diagnosis, Guidance and Education (BRIDGE)-II-MIX multicentric study aimed at evaluating hetero-aggression as a mixed feature during a major depressive episode and its relationship with other clinical variables, such as the lifetime history of suicide attempts. Study IV. Another post-hoc analysis of the BRIDGE-II-Mix study focused on the clinical relevance of the intertwined association between affective lability and mood reactivity and their correlation with other mixed symptoms, particularly verbal or physical hetero-aggression and suicide attempts. Study V. A critical systematic review of guidelines on the treatment of mixed states with a methodological quantitative quality assessment of included articles and a specific focus on challenging aspects such as hetero- and self-aggression. One every fourteen patients suffering from bipolar disorder reported violent criminal behavior. Even though the association with violent criminality was not significant when patients suffering from bipolar disorder were compared with patients suffering from any other psychiatric disorder, the chance of committing violent criminal behavior was smaller in patients with bipolar disorder than in those suffering from psychotic disorders but higher in comparison with patients with depressive disorders. In meta-regression analyses, no significant moderators emerged. The associations for violent criminal behaviors in bipolar disorder in comparison with patients suffering from anxiety, alcohol and drug abuse/dependence and personality disorders were not significant. Mood disorders as well as psychoses, borderline personality disorder and poly-drug use were the most relevant clinical predictors of deliberate self-harm in prison. In the sample of affective patients evaluated during a major depressive episode, the presence of aggressive behaviors was mainly related with bipolarity and the most relevant clinical variable associated with aggression was the presence of mixed features. A significant increase of the risk for aggressive behaviors associated with the presence of lifetime suicide attempts has been observed. As for the association between affective lability with other mixed symptoms, irritable mood and impulsivity were directly significantly associated with affective lability. These two clinical features are two of the most important mediators of self-aggressive behaviors. Despite this, affective lability was not correlated with a higher rate of suicide attempts.
The identification of self- and hetero-aggressive behaviors represented the target of a tailored treatment strategy in the subgroup of bipolar disorder patients characterized by a shared psychopathological “aggressive” dimension and mixed characteristics. in conclusion, the self- and hetero-aggressive components of bipolar disorder have been investigated in this doctoral thesis, leading to a better and broader knowledge on the topic, with important implications for the every-day clinical practice and in terms of treatment strategies, both in psychiatric and in correctional settings.El objetivo principal de esta tesis doctoral fue evaluar los correlatos clínicos de auto o hetero-agresiones, en el contexto del trastorno bipolar, con especial foco en aquellos pacientes que presentan características clínicas mixtas. Los cinco artículos incluidos tenían diseños de estudio diferentes: I. Meta-análisis de estudios sobre la asociación entre trastorno bipolar y conductas criminales violentas; II. Estudio transversal que evalúa los correlatos clínicos de autolesiones e intentos de suicidio en presos, en particular trastornos afectivos y trastorno bipolar; III. Análisis post-hoc del estudio BRIDGE-II-MIX, con el objetivo de evaluar la hetero-agresión considerada como característica mixta durante un episodio depresivo, y su relación con otras variables clínicas, como la historia de intentos de suicidio; IV. Análisis post-hoc del estudio de BRIDGE-II-MIX, enfocado en la importancia clínica de la asociación entrelazada entre la labilidad afectiva y la reactividad de humor y su correlación con otros síntomas mixtos, en particular la hetero-agresión verbal o física; V. Revisión crítica sistemática de guías clínicas sobre el tratamiento de estados mixtos con una evaluación cuantitativa de la calidad metodológica de los artículos incluidos. Uno cada catorce pacientes que padecen de trastorno bipolar presentó una conducta criminal violenta. La posibilidad de cometer una conducta criminal violenta era menor en pacientes con trastorno bipolar que en aquellos que padecen de trastornos psicóticos, pero mayor en comparación con pacientes con trastornos depresivos. Los análisis de meta-regresión no detectaron moderadores significativos. Los trastornos afectivos así como las psicosis, el trastorno límite de personalidad y el consumo de diferentes tóxicos eran los factores clínicos de riesgo más relevantes de autolesiones en la cárcel. En la muestra de pacientes afectivos evaluados durante un episodio depresivo, la presencia de comportamientos agresivos principalmente fue relacionada con la bipolaridad y la variable más relevante clínica asociada con agresión, fue la presencia de características mixtas. Se observó además un aumento significativo del riesgo para comportamientos agresivos asociados con la presencia de intentos suicidas previos. La identificación de comportamientos auto y hetero-agresivos representa el objetivo de una estrategia de tratamiento adaptada en el subgrupo de pacientes con trastorno bipolar, caracterizado por una dimensión psicopatológica "agresiva" compartida.
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Hur, Cem. "Tackling Bipolar Disorder." Thesis, Birmingham City University, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.731716.
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Patterson, Steven Gregory. "Bipolar cascade lasers." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/8805.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.Includes bibliographical references.
This thesis addresses issues of the design and modeling of the Bipolar Cascade Laser (BCL), a new type of quantum well laser. BCLs consist of multiple single stage lasers electrically coupled via tunnel junctions. The BCL ideally operates by having each injected electron participate in a recombination event in the topmost active region, then tunnel from the valence band of the first active region into the conduction band of the next active region, participate in another recombination event, and so on through each stage of the cascade. As each electron may produce more than one photon the quantum efficiency of the device can, in theory, exceed 100%. This work resulted in the first room temperature, continuous-wave operation of a BCL, with a record 99.3% differential slope efficiency. The device was fully characterized and modeled to include light output and voltage versus current bias, modulation response and thermal properties. A new singlemode bipolar cascade laser, the bipolar cascade antiresonant reflecting optical waveguide laser, was proposed and modeled.
by Steven G. Patterson.
Ph.D.
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Pipe, Kevin P. (Kevin Patrick) 1976. "Bipolar thermoelectric devices." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/16614.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.Includes bibliographical references (p. 124-133).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
The work presented here is a theoretical and experimental study of heat production and transport in bipolar electrical devices, with detailed treatment of thermoelectric effects. Both homojunction and heterojunction devices are considered, and particular attention is given to semiconductor laser diodes. The mechanisms that govern both internal heat exchange and heat transfer between a device and its environment are examined, leading to structures which are optimized for thermal management.
by Kevin Patrick Pipe.
Ph.D.
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Walker, Megan Anna Hein. "bipolar[i].discuss()." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23805.
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This MFA thesis uses the medium of computer language to explore the chaos underlying Bipolar I Disorder, an enigmatic and disruptive illness. Using creative coding to generate a series of abstract systems representing human traits, I explore the common truth that pervades the seemingly randomness of mental illness: we all break the same.Master of Fine Arts
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Suvar, Erdal. "SiGeC Heterojunction Bipolar Transistors." Doctoral thesis, KTH, Microelectronics and Information Technology, IMIT, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3674.
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Heterojunction bipolar transistors (HBT) based on SiGeC havebeen investigated. Two high-frequency architectures have beendesigned, fabricated and characterized. Different collectordesigns were applied either by using selective epitaxial growthdoped with phosphorous or by non-selective epitaxial growthdoped with arsenic. Both designs have a non-selectivelydeposited SiGeC base doped with boron and a poly-crystallineemitter doped with phosphorous.
Selective epitaxial growth of the collector layer has beendeveloped by using a reduced pressure chemical vapor deposition(RPCVD) technique. The incorporation of phosphorous and defectformation during selective deposition of these layers has beenstudied. A major problem of phosphorous-doping during selectiveepitaxy is segregation. Different methods, e.g. chemical orthermal oxidation, are shown to efficiently remove thesegregated dopants. Chemical-mechanical polishing (CMP) hasalso been used as an alternative to solve this problem. The CMPstep was successfully integrated in the HBT process flow.
Epitaxial growth of Si1-x-yGexCy layers for base layerapplications in bipolar transistors has been investigated indetail. The optimization of the growth parameters has beenperformed in order to incorporate carbon substitutionally inthe SiGe matrix without increasing the defect density in theepitaxial layers.
The thermal stability of npn SiGe-based heterojunctionstructures has been investigated. The influence of thediffusion of dopants in SiGe or in adjacent layers on thethermal stability of the structure has also been discussed.
SiGeC-based transistors with both non-selectively depositedcollector and selectively grown collector have been fabricatedand electrically characterized. The fabricated transistorsexhibit electrostatic current gain values in the range of 1000-2000. The cut-off frequency and maximum oscillation frequencyvary from 40-80 GHz and 15-30 GHz, respectively, depending onthe lateral design. The leakage current was investigated usinga selectively deposited collector design and possible causesfor leakage has been discussed. Solutions for decreasing thejunction leakage are proposed.
Key words:Silicon-Germanium-Carbon (SiGeC),Heterojunction bipolar transistor (HBT), chemical vapordeposition (CVD), selective epitaxy, non-selective epitaxy,collector design, high-frequency measurement, dopantsegregation, thermal stability.
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Knowles, Rebecca Elizabeth. "Psychology of bipolar disorder." Thesis, University of Manchester, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488262.
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A behavioural high risk paradigm was used to investigate cognitive vulnerability to bipolar disorder in a group of individuals at high risk of developing symptoms, and similar measures were administered to a group of bipolar patients whose symptoms were currently in remission. High risk was defined as a combination of elevated scores on both the Hypomanic Personality Questionnaire and the Dysfunctional Attitudes Scale. The research addressed several psychological models of bipolar disorder including response styles, behavioural engagement, circadian rhythm disruption, self-esteem instability and the manic defence, as well as cognitive reactivity to musical mood induction and the impact of mood on emotion recognition. In the initial analogue study, hypothetically low-, medium- and high-risk participants were compared on measures of the models listed. High-risk participants displayed a uniquely dysfunctional combination of rumination and risk-taking coping behaviours, high behavioural inhibition and activation scores, irregular and unrestful sleep, highly unstable self-esteem, heightened sensitivity to positive and negative mood induction, and a moodcongruent bias in their perception of ambiguous facial expressions relative to the low-risk participants. They had also experienced significant levels of affective symptomatology consistent with their high-risk status. The subsequent clinical study compared remitted bipolar patients to remitted unipolar depressed patients and healthy controls. The bipolar group displayed more ruminative coping, high behavioural inhibition, disrupted and inefficient sleep, unstable selfesteem, and a clear manic defence when compared to the controls. The remitted bipolar patients also reported greater shifts in mood and self-esteem following both mood induction procedures than the controls. The remitted bipolar patients were therefore very similar to both the unipolar depressed group and the high-risk analogue participants in cognitive terms. Taken together, the results support the use of behavioural high-risk paradigms in investigations of bipolar disorder, and confirm the involvement of the presently examined cognitive and psychosocial factors in conferring vulnerability to bipolar symptomatology.
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Wittchen, Hans-Ulrich, Stephan Mühlig, and Lukas Pezawas. "Natural course and burden of bipolar disorders." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-117282.
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Despite an abundance of older and more recent retrospective and considerably fewer prospective-longitudinal studies in bipolar disorders I and II, there are still remarkable deficits with regard to our knowledge about the natural course and burden. The considerable general and diagnosis-specific challenges posed by the nature of bipolar disorders are specified, highlighting in particular problems in diagnostic and symptom assessment, shifts in diagnostic conventions and the broadening of the diagnostic concept by including bipolar spectrum disorders. As a consequence it still remains difficult to agree on several core features of bipolar disorders, such as when they begin, how many remit spontaneously and how many take a chronic course. On the basis of clinical and epidemiological findings this paper summarizes (i) a significant need to extend the study of the natural course of bipolar disorder in clinical samples beyond the snapshot of acute episodes to the study of the mid-term and long-term symptom course, associated comorbidities and the associated burden of the disease. (ii) In terms of epidemiological studies, that are also of key importance for resolving the critical issues of threshold definitions in the context of the bipolar spectrum concept, there is a clear need for identifying the most relevant risk factors for the first onset and those for the further illness progression in early stages. Since there are some indications that these critical processes might start as early as adolescence, such studies might concentrate on young cohorts and clearly before these prospective patients come to clinical attention. (iii) The value of both types of studies might be enhanced, if beyond the use of standardized diagnostic interview, special attempts are made to use prospective life- and episode-charting methods for bipolar illnesses.
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Nayeem, Mustayeen B. "Applied mechanical tensile strain effects on silicon bipolar and silicon-germanium heterojunction bipolar devices." Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-07182005-102447/.
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Thesis (M. S.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2006.Dr. John D. Cressler, Committee Chair ; John Papapolymerou, Committee Member ; Joy Laskar, Committee Member.
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Hillegers, Manon Hubertine Johanna. "Developing bipolar disorder a follow-up study among children of patients with bipolar disorder /." [S.l. : [Groningen : s.n.] ; University Library Groningen] [Host], 2007. http://irs.ub.rug.nl/ppn/301812861.
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Eklund, Rebecca. "”Hade jag inte haft den hade jag nog inte alls varit den jag är idag” : En kvalitativ studie om identitet hos människor med bipolär sjukdom." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79955.
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Syftet med studien var att undersöka hur bipolär sjukdom kan påverka en människas identitet. Tidigare forskning har föreslagit att människor med bipolär sjukdom kan ha svårt att identifiera vem de verkligen är och att de kan ha en mindre utvecklad identitet. I denna kvalitativa studie genomfördes tio djupintervjuer som sedan kodades. En tematisk analys utfördes. Fyra teman identifierades: Uppfattning om identitet, acceptans, föräldraskap och sjukdomens påverkan på livet. En övervägande del av respondenterna uppgav att sjukdomen är en del av deras identitet, detta motsäger tidigare forskning. Acceptans uppges ske i olika steg och förenkla livet när sjukdomen väl är accepterad, forskning stöder detta fynd. Respondenterna beskriver en rädsla att sjukdomen ska påverka föräldraskap eller att sjukdomen redan har påverkat föräldraskapet. Flera respondenter uppger att sjukdomen har lett till ett misslyckat föräldraskap vilket, enligt tidigare forskning, kan leda till mindervärdeskomplex. Sjukdomen anses i övervägande del påverka livet negativt och skapa en funktionsnedsättning. Flera respondenter uppgav att sjukdomen har varit ett hinder i deras arbete och enligt forskning kan även detta påverka respondenternas uppfattning om eget värde negativt. Bipolär sjukdom anses i denna studie påverka identiteten kraftigt och i största mån negativt. Fortsatt forskning bör fokusera på ”mixet-method” studier med kvantitativa korrelationer mellan till exempel typ av bipolär sjukdom och grad av funktionsnedsättning.The purpose of this study was to investigate how bipolar disorder affects a person’s identity. In this qualitative study ten in-depth interviewes were conducted. The interviews were seperated into pieces that were assigned a specific code and a thematic analysis was performed. Four themes were identified: perception of identity, acceptance, parenting and the impact of the illness on life. The majority of the participants stated that the disease is part of their identity, which contradicts previous research. Acceptance is stated to occur in various stages and simplifies life once the disease is well accepted, reasearch supports this finding. Participants described a fear that the disease will affect parenthood or that the disease has already affected parenthood. Several participants stated that the disease has led to failed parenting which, according to previous research, can lead to inferiority complex. The disease is predominantly affecting life negatively and creating disability. Several participants stated that the disease has been an obstacle in their career and according to research this can also have a negative impact on the participants’ perception of their own value. In this study, bipolar disorder is considered to have a strong negative impact on identity. Continued research should focus on “mixed-methods” studies with quantitative correlations between for example type of bipolar disorder and level of disability.
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Chabler, Leslie Anne. "Familial factors in bipolar disorder." Connect to resource, 1987. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=osu1244209127.
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Ortiz-Dominguez, Tania Abigail. "Migraine comorbidity in bipolar disorder." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116105.
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Introduction: Bipolar Disorder (BD) is a chronic mental illness associated with functional decline, mortality, and significant health care costs; furthermore, specific general medical conditions have been found to occur disproportionately within BD patient populations, among them, migraine is one of the most studied. Migraine has a global prevalence of 10%, and it is a disorder with elevated direct and indirect costs, the later mostly derived from its association with mood and anxiety disorders. Specifically, the reported prevalence of migraine in the BD population ranges from 24.8% to 39.8%, rates that are considerable higher than those found in the general population.Objective: To explore the prevalence and clinical characteristics of BD patients with and without migraine (Study 1), and to examine the psychiatric comorbidity in patients suffering from migraine (Study 2).
Methods: 323 BD patients were studied, using SADS-L and SCID as diagnostic interviews, and ill-Migraine questionnaire to assess the presence of migraine. Statistical analyses were conducted using parametric analysis and the development of log-linear models. Additionally, 102 migraine patients were interviewed using SADS-L, and the descriptive characteristics of the sample were analyzed.
Results: For Study 1, we found that 24.5% of BD patients suffer from migraine, and it is significantly associated with BD 2, suicidal behaviour, and a variety of anxiety disorders. As well, over 70% of migraine patients showed a lifetime psychiatric diagnosis, mainly within the spheres of mood and anxiety disorders; specifically, the prevalence of BD among migraine patients was 12.7%.
Conclusions: Our study highlights the high prevalence of migraine among BD patients, and the elevated prevalence of psychiatric comorbidity among migraine sufferers. The study of this comorbidity will deepen our understanding of the mechanisms that underlie both disorders and provide a better framework for the developing of molecular techniques to further analyze the molecular physiopathology of Bipolar Disorder.
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Clark, Luke. "Neuropsychological investigations in bipolar disorder." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368012.
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Cole, Sarah. "Risk taking in bipolar disorder." Thesis, University of Hull, 2009. http://hydra.hull.ac.uk/resources/hull:2400.
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Part 1 Background: People with a diagnosis of bipolar disorder can make suboptimal decisions during manic and depressive episodes which can have negative long-term consequences. This review aims to explore individual factors, including mood state and personality traits, which could affect decision making processes of individuals with bipolar disorder. Methods: A systematic search of three databases, plus hand searching relevant reference sections, identified twenty five relevant studies, nineteen of which met the inclusion criteria for the review. Results: Mania and severe depression are associated with poorer performance on computerised tasks designed to measure risk decision making. There is tentative evidence for altered decision making processes even during euthymic and remitted phases of bipolar disorder, but little difference in overall decision making outcomes. Limitations: The evidence base is small and centred around a few computerised tasks, which may have limited ecological validity in the assessment of decision making. Complex decision making tasks are difficult to interpret in terms of underlying processes. Conclusions: Both mood episode and trait factors, such as impulsivity, may have some predictive value of decision making in people with a diagnosis of bipolar disorder, although trait factors are largely unexplored in this population. Further research is needed to develop a psychological model for understanding the relative impact of individual factors, plus social and environmental factors which can influence the decision making process. Part 2 "Excessive" risk taking behaviour is a clinical characteristic of a manic episode, which can lead to harmful consequences for the individual with bipolar disorder. This study investigated the hypothesis that risk taking behaviour may be more sensitive to change following mood induction in people with bipolar disorder than in controls. Participants were 26 people with bipolar I disorder who were out of an acute episode and 28 healthy controls. Risk taking was measured using the Balloon Analogue Risk Task (BART; Lejuez et al, 2002), a computerised task that has been found to correlate with real world risky behaviours. After baseline measures, participants were randomly assigned positive or negative mood induction and completed two sets of BART trials, before and after mood induction. Trait sensitivity to reward was also measured, as a potential factor underlying BART performance. The primary hypothesis was not supported by the findings, nor could the variance in risk taking before or after mood induction be explained by trait sensitivity to the behavioural activation system. The bipolar group demonstrated less risk taking at baseline than controls. The results suggest excessive risk taking behaviour may be specifically associated with manic symptoms other than positive affect. However people with bipolar disorder may make poorer quality risk decisions out of an acute episode than controls.
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Smith, Angela Mary. "Psychological Processes in Bipolar Disorder." Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492751.
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The present research addressed several diathesis models of bipolar disorder including Behavioural Activation, stress sensitivity and circadian rhythm disruption and considered cognitive vulnerability factors such as self-esteem and affective instability, response styles to depression and depressogenic cognitive styles. These relationships were examined prospectively in healthy controls, remitted unipolar patients and bipolar disorder participants who were remitted, depressed or hypomanic.
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Antoniou, M. A. "SuperJunction insulated gate bipolar transistor." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.596130.
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The main achievement of this work is that we show that by intelligently coupling the ideas and designs from various power semiconductor devices, that do not combine under conventional approaches, we can lower the turn-off losses by a factor of 5 (or more) when compared to state-of-the-art medium-high voltage power devices, while maintaining a similarly low on-state voltage drop. In this work we propose an optimised SuperJunction IGBT. The impact of varying the net doping of the n and p drift layer pillars was investigated and the device was optimised to deliver the best trade-off between the on-state and switching performance through extensive numerical simulations, both at room and high temperatures. A PSPICE based model of the SuperJunction IGBT was also developed. The results obtained are in good agreement with the device simulations results. The model allows engineers access to a simple and cheap tool to test and evaluate the performance of the SJIGBT. This model consists of an intrinsic MOSFET and a parallel combination of a wide and a narrow base pnp BJTs. A parasite JFET is also included to account for the restricted current flow between two adjacent p-wells. Here we propose a Semi Superjunction IGBT that maintains a high static and dynamic avalanche breakdown while improving dramatically (by one to two orders of magnitude) the failure rate under cosmic ray exposure. This is unrepentant for any other devices in the field. As a result, this device can provide the solution to unexpected power device breakdowns and therefore save the cost in replacing them and the distraction caused. In the same manner, the introduction of the ‘disconnected p-pillar’ in the Semi-SJIGBT dramatically improves the on-state performance and switching-off speed of the device when compared to the conventional Field Stop IGBT.
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Woods, Stephen John. "Simulation of photoactivated bipolar devices." Thesis, University of East Anglia, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267275.
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Taylor, Jayne Louise. "Self-representations in bipolar disorder." Thesis, University of Leeds, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416487.
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NASCIMENTO, RODRIGO LEAO FERREIRA DO. "IMPLICIT INSIGHT INTO BIPOLAR DISORDER." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=34485@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Prejuízo de insight costuma ser reportado no Transtono Bipolar (TB), sobretudo quando os pacientes viram para o pólo maníaco do transtorno. Essa falha na consciência verbal dos déficits, sinais e sintomas do transtorno pode vir acompanhada de uma forma de insight implícito, que é a demonstração indireta de algum nível de conhecimento sobre a doença ou uma deficiência com perda parcial ou total de reconhecimento verbal. Dois estudos foram conduzidos para verificar as relações entre as formas de insight explícito e implícito no TB. Para isso, foi utilizado um modelo teórico conhecido como The Cognitive Awareness Model (CAM), que permite investigar dissociações nos padrões de consciência implícita e explícita. No primeiro estudo, os participantes foram avaliados em relação à uma série de variáveis clínicas, incluindo uma medida de insight explícito, além de uma medida de insight implícito com estímulos ligados à depressão e à mania. No segundo estudo, os participantes foram igualmente testados em relação às variáveis clinicas, incluindo uma medida de insight explícito, além de uma medida de insight implícito com estímulos ligados à condição de saudável e doente. Os resultados de ambos os estudos apontaram para diferenças nas medidas de insight explícito entre os grupos de maníacos e eutímicos, e demonstraram diferenças no tempo médio de reação para auto-associações implícitas para condição. A partir desses resultados, pode-se sugerir que os pacientes em mania se autoavaliam explicitamente de forma similar aos pacientes em eutimia, o que pode trazer prejuízos na adesão ao tratamento, ao passo que os pacientes bipolares apresentaram uma forma de insight implícito tanto para os sintomas quanto para a condição de doente avaliadas.
Lack of insight is usually reported in Bipolar Disorder (TB), especially when patients have seen the manic pole of the disorder. This lack of verbal awareness of deficits, signs and symptoms of the disorder may be accompanied by an implicit insight, which is the indirect demonstration of some level of knowledge about the disease or a disability with partial or total loss of verbal recognition. Two studies were conducted to verify the relationships between explicit and implicit forms of insight into TB. For this, a theoretical model known as The Cognitive Awareness Model (CAM) was used, which allows to investigate dissociations in the patterns of implicit and explicit consciousness. In the first study, participants were assessed for a number of clinical variables, including an explicit insight measure, as well as an implicit insight measure with depression and mania-related stimuli. In the second study, participants were also tested for clinical variables, including an explicit insight measure, as well as an implicit insight measure with stimuli linked to healthy and ill status. The results of both studies pointed to differences in measures of explicit insight between the manic and euthymic groups and demonstrated differences in mean reaction time for implied self-associations for condition. From these results, it can be suggested that patients in mania explicitly self-evaluate in a similar way to patients in euthymia, which can lead to impairment in adherence to treatment, whereas bipolar patients presented an implicit insight for symptoms and for the patient s condition evaluated.
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Kandaswamy, R. "Molecular genetics of bipolar disorder." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1370613/.
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Bipolar affective disorder has a strong genetic heritability. In the UCL laboratory, a locus on chromosome 1p36 was found to be linked to bipolar and related unipolar affective disorders with a log of the odds score above 3.00. This region was subjected to fine mapping using tests of allelic association in a case-control sample as part of this thesis in order to identify the genes involved in bipolar disorder. In addition, a GWAS was also employed to fine map other bipolar affective disorder susceptibility genes. The tests of allelic association found evidence for the involvement of the PRKCZ gene. Markers D1S243 and rs3128396 at the PRKCZ gene were significantly associated with bipolar disorder with empirical P = 0.037 and P = 0.040, respectively. Other loci encoding brain expressed proteins found to be associated in the UCL GWAS sample were the genes - GRM3 and GRM7. Therefore, these genes were sequenced using PCR-based genomic sequencing. A 3'-UTR base pair change (rs56173829) in the GRM7 gene was found to be significantly associated with the disorder, although the minor allele was more frequent in controls. A base pair mutation (rs148754219) was found in the GRM3 exon 1 two bases before the translation start codon (forming part of Kozak sequence) of a GRM3 receptor isoform. The mutation was associated with bipolar disorder (P = 0.0046, odds ratio 4.2 (95% CI 1.42-12.37)). Transcription factor binding assays and cloning experiments comparing the gene expression activity of wild-type and mutant alleles showed that the mutant allele strongly affected the reporter gene activity in SH-SY5Y and HEK293 cells. If the GRM3 Kozak sequence mutation is confirmed as an important mutation in the aetiology of bipolar disorder, then it could be used as a marker for personalised treatment for a genetic subtype of affective disorders.
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Rock, Philippa L. "Emotional processing and bipolar disorder." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:f4a311fe-3bda-40cc-852a-11dbde8f436c.
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The aetiology of bipolar disorder remains unclear and investigation to date has focussed largely on bipolar patients. Whilst ultimately of huge value, such studies may also be confounded by current mood or experience of repeated illness episodes or current or past medication; using at-risk samples may bypass some of these problems. The current research therefore assessed the efficacy of the Mood Disorder Questionnaire (MDQ) as a screening tool for vulnerability to bipolar disorder. The MDQ was used with two sets of criteria to identify two sub-groups of medication-naïve young bipolar phenotype subjects who were at risk for bipolar disorder by virtue of experience of mood elevation. Analysis of data from the Student Stress Survey was carried out to characterise the bipolar phenotype. Compared to a control group with no experience of mood elevation, the two bipolar phenotype sub-groups showed a gradient of prevalence of bipolar diagnosis and associated co-morbidity. Behavioural and functional magnetic resonance imaging (fMRI) techniques were employed to investigate emotional processing, decision-making, and sleep and circadian rhythmicity in bipolar phenotype students. Analyses revealed that positive emotional processing biases, disrupted decision-making, and increased activity during sleep were associated with the bipolar phenotype and, therefore, may represent vulnerability markers for bipolar disorder. Finally, a psychopharmacological investigation of quetiapine, which stabilises mood, was carried out in healthy volunteers. One-week quetiapine administration resulted in biases away from both positive and negative emotional stimuli (i.e. a mood-stabilising effect), reduced discrimination between different magnitudes of gains and losses during risky decision-making (consistent with an antidepressant effect), and increased sleep duration. In sum, this research has developed our understanding of vulnerability markers associated with the bipolar phenotype and provided a first step towards uncovering the psychological mechanisms through which quetiapine’s clinical effects may be mediated.
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Weathers, Judah D. "Cognitive functioning in bipolar disorder." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:6a73683c-0047-4285-a251-2414a0f64d0f.
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To align the neuropsychological functioning of our adult euthymic patient group with that reported in previous studies on euthymic bipolar disorder (BD), we used a neuropsychological battery that examined sustained attention (Rapid Visual Information Processing Task), verbal memory (California Verbal Learning Task), executive functioning (Intradimensional-Extradimensional Shift Task, Barrett Impulsivity Task, and Framing Task), and emotion responsiveness/regulation (Positive Affect/Negative Affect Scales, Behavioral Inhibition/Behavioral Activation Scale, and Affective Lability/Affective Intensity Scales) in patients versus healthy volunteers (HV). Our results corroborated existing evidence of reduced sustained attention, impaired verbal memory and executive functioning, and abnormal emotional responsiveness and regulation in euthymic BD relative to healthy controls (Chapter 2). To investigate how abnormal development of brain function in BD leads to deficits in decision-making, motor inhibition, and response flexibility, we examined child and adult BD using a novel risky decision-making task, and used cross-sectional (age x diagnosis) functional magnetic resonance (fMRI) designs to examine neural activation associated with motor inhibition and response flexibility in BD relative to HV. During the risky decision-making task, adult euthymic BD patients were no different from healthy controls in their proportion of risky lottery choices over a range of competing lotteries. This matched behavioral performance was associated with similar prefrontal and striatal brain activation between the patient and control groups during response, anticipation, and outcome phases of decision-making (Chapter 3). These results are different from previous studies that have shown increased risk taking during decision-making in euthymic BD. Similarly, young BD patients were no different from age-matched healthy and patient controls in their pattern of decision making during the risky choice task. This was evidenced by a similar number of risky lottery selections over the range of changing expected values between the young BD group and control groups (Chapter 4). Using a cross-sectional, fMRI analytic design during the stop signal task, we found that child and adult BD showed similar behavioral performance to child and adult HV during motor inhibition. However, this matched behavioral performance was associated with abnormal neural activation in patients relative to controls. Specifically, during unsuccessful motor inhibition, there was an age group x diagnosis interaction, with BD youth showing reduced activity in left and right ACC compared to both age-matched HV and adult BD, and adult BD showing increased activation in left ACC compared to healthy adults. During successful motor inhibition there was a main effect of diagnosis, with HV showing greater activity in left VPFC and right NAc compared to BD (Chapter 5). These neuroimaging data support existing laboratory-based evidence of motor inhibition impairments in BD relative to HV, and indicate brain dysregulation during motor control is important to BD pathophysiology. A previous behavioral study showed impaired response flexibility in young BD patients relative to age-matched controls when using the change task. Here, we used the change task during fMRI to examine response flexibility in child and adult BD compared to child and adult HV. We found that patient and control groups showed similar change signal reaction times in response to change cues. However, this matched behavioral performance was associated with abnormal age group x diagnosis activations in brain regions important in signal detection, response conflict, response inhibition, and sustained attention. Specifically, during successful change trials, child BD participants showed frontal, parietal, and temporal hyperactivation relative to healthy children and adult BD, while adult BD showed hypoactivation in these regions relative to healthy adults. These novel fMRI findings during the change task indicate impaired neural activation during response flexibility may be important to the pathophysiology of BD development.
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Post, Ian R. C. "PNP polysilicon emitter bipolar transistors." Thesis, University of Southampton, 1992. https://eprints.soton.ac.uk/394020/.
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Brietzke, Elisa Macedo. "Mediadores inflamatórios no transtorno bipolar." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/24601.
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Objetivos: Comparar os níveis séricos de citocinas entre voluntários saudáveis e em pacientes bipolares tipo 1 em mania, depressão e eutimia. Comparar os níveis séricos de quimiocinas entre voluntários saudáveis e pacientes bipolares tipo 1 em eutimia. Metodologia: Sessenta e um pacientes bipolares foram recrutados para a avaliação dos níveis séricos de citocinas. Desses, 24 estavam eutímicos, e 23 e 24 estavam em mania e depressão, respectivamente. Este grupo foi comparado a outro, composto por 25 voluntários saudáveis. As seguintes citocinas foram exainadas através de citometria de fluxo: TNF-alfa, IL-2, IL-4, IL-6, IL-10, IFN-gama e comparadas entre os grupos. Além dessa análise, 30 pacientes bipolares tipo 1 foram comparados a igual número de voluntários saudáveis para estudar os níveis séricos das seguintes quimiocinas: CCL2, CCL3, CCL8, CCL 9, CCL10, CCL11 e CCL24, dosadas através de ELISA sandwich. Resultados: Duarnte a mania, as citocinas pró-inflamatórias IL-2, IL-4 e IL-6 estavam elevadas nos pacientes com TB em comparação com o grupo de voluntários saudáveis. Já os pacientes em episódio depressivo, apresentavam somente elevação da IL-6. Não houve modificação dos níveis de citocinas nos pacientes eutímicos, exceto pelo aumento da IL-4. Quanto as quimiocinas, enquanto os níveis séricos de CXCL10 estavam elevados nos pacientes bipolares, os níveis de CCL24 estavam diminuídos.Objectives: Compare serum levels of cytokines between healthy volunteers and patients with bipolar disorder type 1 in mania, depression and euthymia. Compare serum levels of chemokines between healthy volunteers and bipolar patients in euthymia. Methods: Sixty-one bipolar patients were recruited for assessment of serum cytokine levels. Of these, 14 were in euthymic state, 23 and 24 were in manic and depressive episodes, respectively. A healthy comparison group included 25 healthy volunteers. Cytokines involved in Th1/Th2 balance, such as TNF- , IL-2, IL-4, IL-6, IL-10, IFN- , were examined by flow cytometry. In addition, serum chemokine levels of 30 euthymic patients with BD type I and 30 healthy volunteers were investigated and compared. The chemokines assessed were CCL2, CCL3, CCL8, CCL 9, CCL10, CCL11, and CCL24. Results: During mania, proinflammatory cytokines, IL-2, IL-4 and IL-6, were increased in comparison with healthy subjects. Patients in depressive episode showed only increased IL-6 levels. There were no significant differences in cytokine levels between patients in remission and healthy subjects, except for IL-4. Regarding chemokines, patients with BD showed significant differences in chemokine levels when compared with healthy subjects. While serum levels of CXCL10 were increased, CCL24 levels were lower in bipolar patients when compared with controls. There was no statistical difference in the serum levels of CCL2, CCL3, CCL24, CXCL9, and CXCL11 between patients and controls.
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LEBOWITZ, BRIAN K. "INHIBITORY CONTROL IN BIPOLAR DISORDER." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1093016997.
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Pavlickova, Hana. "Psychological vulnerability in bipolar disorder." Thesis, Bangor University, 2013. https://research.bangor.ac.uk/portal/en/theses/psychological-vulnerability-in-bipolar-disorder(7a7c7ece-e279-4477-93f8-046c035dc500).html.
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Background: The current understanding of bipolar disorder attributes a causal role to abnorma1 psychological processes in its development. However, little research has so far adequately tested this assumption. Two approaches might be employed to do so: (i) longitudinal investigations of psychological processes in patients (with some limitations); (ii) examinations of such processes in high-risk individuals. Methods: Three cohorts of participants were examined: two different cohorts of adults with bipolar disorder (using secondary data, Chapter 2 and 3), and adolescent offspring of parents with bipolar disorder, in comparison to offspring of control parents (Chapters 4, 5, 6). In adults with bipolar disorder, the associations between self-referential processes and symptoms of depression and mania (Chapter 2), and the inter-relationship between self-esteem, mood and response styles (Chapter 3) were examined longitudinally. In adolescent children, longitudinal relationship between mood, self-esteem and coping style (Chapter 4), abnormal psychological processes (Chapter 5), and explicit and implicit self-esteem and their discrepancies (Chapter 6), were investigated. Results: In adults with bipolar disorder, symptoms of depression and mania were associated with distinct psychological processes, with self-esteem being the most robust predictor (Chapter 2). However, mood, rather than self-esteem, instigated, and was affected by, an engagement in coping strategies (Chapter 3). In adolescents, index adolescents showed compromised capacity to employ adaptive coping, and employed risktaking in response to low self-esteem (Chapter 4). Further, no differences in abnormal psychological processes were found, unless children have already met diagnostic criteria for psychiatric disorders (Chapter 5). Despite no differences in explicit and implicit self-esteem, index offspring reported marginally higher level of self-esteem discrepancies. In addition, damaged self-esteem (i.e. low explicit self-esteem and high implicit self-esteem) was related to symptoms of depression, whilst low implicit self-esteem to symptoms of mania. Conclusions: Early coping abnormalities are important markers of individuals at ultra high lisk of bipolar disorder. Further, the relevance of self-esteem in bipolar disorder has been suggested. Implications for future research and psychotherapy are discussed.
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Rindone, Fabio. "The bipolar Choquet Integral Representation." Thesis, Università degli Studi di Catania, 2011. http://hdl.handle.net/10761/285.
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We present the bipolar Cumulative Prospect Theory, a generalization of Cumulative Prospect Theory of Kahneman and Tversky. Moreover we get a characterization of the Choquet Integral with
respect to a bi-capacity in a discrete setting. With our model we are able to explain some recent
paradoxes regarding the separate valuation of gains and losses within a
mixed gamble.We present the bipolar Cumulative Prospect Theory, a generalization of Cumulative Prospect Theory of Kahneman and Tversky. Moreover we get a characterization of the Choquet Integral with respect to a bi-capacity in a discrete setting. With our model we are able to explain some recent paradoxes regarding the separate valuation of gains and losses within a mixed gamble.
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Manda, Malleswar. "Modeling of self heating effects in hetrojunction bipolar transistors and implementation in spice software." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1178213156.
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Zhang, Yun. "Development of III-nitride bipolar devices: avalanche photodiodes, laser diodes, and double-heterojunction bipolar transistors." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42703.
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This dissertation describes the development of III-nitride (III-N) bipolar devices for optoelectronic and electronic applications. Research mainly involves device design, fabrication process development, and device characterization for Geiger-mode gallium nitride (GaN) deep-UV (DUV) p-i-n avalanche photodiodes (APDs), indium gallium nitride (InGaN)/GaN-based violet/blue laser diodes (LDs), and GaN/InGaN-based npn radio-frequency (RF) double-heterojunction bipolar transistors (DHBTs). All the epitaxial materials of these devices were grown in the Advanced Materials and Devices Group (AMDG) led by Prof. Russell D. Dupuis at the Georgia Institute of Technology using the metalorganic chemical vapor deposition (MOCVD) technique.
Geiger-mode GaN p-i-n APDs have important applications in DUV and UV single-photon detections. In the fabrication of GaN p-i-n APDs, the major technical challenge is the sidewall leakage current. To address this issue, two surface leakage reduction schemes have been developed: a wet-etching surface treatment technique to recover the dry-etching-induced surface damage, and a ledged structure to form a surface depletion layer to partially passivate the sidewall. The first Geiger-mode DUV GaN p-i-n APD on a free-standing (FS) c-plane GaN substrate has been demonstrated.
InGaN/GaN-based violet/blue/green LDs are the coherent light sources for high-density optical storage systems and the next-generation full-color LD display systems. The design of InGaN/GaN LDs has several challenges, such as the quantum-confined stark effect (QCSE), the efficiency droop issue, and the optical confinement design optimization. In this dissertation, a step-graded electron-blocking layer (EBL) is studied to address the efficiency droop issue. Enhanced internal quantum efficiency (ɳi) has been observed on 420-nm InGaN/GaN-based LDs. Moreover, an InGaN waveguide design is implemented, and the continuous-wave (CW)-mode operation on 460-nm InGaN/GaN-based LDs is achieved at room temperature (RT).
III-N HBTs are promising devices for the next-generation RF and power electronics because of their advantages of high breakdown voltages, high power handling capability, and high-temperature and harsh-environment operation stability. One of the major technical challenges to fabricate high-performance RF III-N HBTs is to suppress the base surface recombination current on the extrinsic base region. The wet-etching surface treatment has also been employed to lower the surface recombination current. As a result, a record small-signal current gain (hfe) > 100 is achieved on GaN/InGaN-based npn DHBTs on sapphire substrates. A cut-off frequency (fT) > 5.3 GHz and a maximum oscillation frequency (fmax) > 1.3 GHz are also demonstrated for the first time. Furthermore, A FS c-plane GaN substrate with low epitaxial defect density and good thermal dissipation ability is used for reduced base bulk recombination current. The hfe > 115, collector current density (JC) > 141 kA/cm², and power density > 3.05 MW/cm² are achieved at RT, which are all the highest values reported ever on III-N HBTs.
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Sobczak, Sjacko. "Serotonin and bipolar disorders serotonergic vulnerability in first-degree relatives of patients with bipolar disorder /." [Maastricht : Maastricht : Universiteit Maastricht] ; University Library, Maastricht University [Host], 2002. http://arno.unimaas.nl/show.cgi?fid=7073.
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Wittchen, Hans-Ulrich, Stephan Mühlig, and Lukas Pezawas. "Natural course and burden of bipolar disorders." Technische Universität Dresden, 2003. https://tud.qucosa.de/id/qucosa%3A27010.
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Despite an abundance of older and more recent retrospective and considerably fewer prospective-longitudinal studies in bipolar disorders I and II, there are still remarkable deficits with regard to our knowledge about the natural course and burden. The considerable general and diagnosis-specific challenges posed by the nature of bipolar disorders are specified, highlighting in particular problems in diagnostic and symptom assessment, shifts in diagnostic conventions and the broadening of the diagnostic concept by including bipolar spectrum disorders. As a consequence it still remains difficult to agree on several core features of bipolar disorders, such as when they begin, how many remit spontaneously and how many take a chronic course. On the basis of clinical and epidemiological findings this paper summarizes (i) a significant need to extend the study of the natural course of bipolar disorder in clinical samples beyond the snapshot of acute episodes to the study of the mid-term and long-term symptom course, associated comorbidities and the associated burden of the disease. (ii) In terms of epidemiological studies, that are also of key importance for resolving the critical issues of threshold definitions in the context of the bipolar spectrum concept, there is a clear need for identifying the most relevant risk factors for the first onset and those for the further illness progression in early stages. Since there are some indications that these critical processes might start as early as adolescence, such studies might concentrate on young cohorts and clearly before these prospective patients come to clinical attention. (iii) The value of both types of studies might be enhanced, if beyond the use of standardized diagnostic interview, special attempts are made to use prospective life- and episode-charting methods for bipolar illnesses.
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Blid, Nilsson Tobias, and Marko Lindsjö. "Ett bipolärt liv : Erfarenheter av bipolär sjukdom." Thesis, Högskolan Kristianstad, Sektionen för hälsa och samhälle, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-9013.
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Bipolär sjukdom är en kronisk sjukdom där personen upplever maniska och depressiva perioder. Under manin får personen en ökad energinivå, tankarna flödar samt omdömet försämras. Depressionen kännetecknas av nedstämdhet och en dyster sinnesstämning. Syftet med denna studie var att beskriva vilka erfarenheter en person har av att leva med bipolär sjukdom. En narrativ analys har använts. Denna bygger på fyra självbiografier. I resultatet framkom det att det kan ta lång tid innan diagnosen ställs och därmed rätt behandling sätts in. Samtidigt är det vanligt att patienterna slutar ta sina mediciner på grund av biverkningar. Personer med bipolär sjukdom känner ofta oro och ångest inför att insjukna i nya maniska eller depressiva perioder. Känslor som oro och ångest kan i kombination med depressiva perioder leda till självskadebeteende. Till exempel att de skär sig. Den som drabbas av bipolär sjukdom kan ha stor nytta av familjen som skyddsnät. Även andra personer som är i en likande situation kan vara ett stort stöd.Bipolar disorder is a chronic disease where the person experiencing manic and depressive episodes. During mania has the person an increased energy level, the thoughts flow and impaired reviewed. Depression is characterized by sadness and a gloomy mood. The purpose of this study was to describe the experience a person has to live with bipolar disorder. A narrative analysis was used. This is based on four autobiographies. The results showed that it can take a long time before getting diagnosed and therefore the appropriate treatment. While it is common that patients stop taking their medications because of side effects. People with bipolar disorder often feel anxiety before falling ill with manic or depressive episodes. Emotions such as worry and anxiety can be combined with depressive episodes lead to self-injury. For example, they cut themselves. Those who suffer from bipolar disorder can benefit greatly from their family as a safety-net. Even other people who are in a similar situation can be a great support.
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McCabe, Patrick J. "Cannabis Use and Bipolar Disorder: Bipolar Disorder Case Identification and Cannabis Use Risk Assessment: A Dissertation." eScholarship@UMMS, 2011. https://escholarship.umassmed.edu/gsbs_diss/584.
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Bipolar disorders (BD) are characterized by symptoms of grandiosity, decreased need for sleep, pressure to keep talking, flight of ideas, distractibility, increased goal-directed activities, psychomotor agitation, and excessive involvement in pleasurable activities. Those with a bipolar disorder have a high degree of psychiatric comorbidity including substance use disorders, and they also experience increased mortality. Despite the widespread recognition of BD as an important psychiatric condition, available population-based estimates for BD prevalence differs across data sources.
Cannabis is one of the most widely-used illicit substances. Evidence supports it as a risk factor for psychotic symptoms and disorders. Because populations with psychotic disorders and populations with bipolar disorder share genetic characteristics, cannabis may increase risk for bipolar disorders through the same pathways as it does with psychotic disorders. Limited and conflicting evidence regarding the association of cannabis use and bipolar disorder is currently available. This dissertation investigates cannabis use as a risk factor for incident manic symptoms and bipolar disorders in a large nationally representative longitudinal cohort.
The first aim of this dissertation is to evaluate the implications for manic, hypomanic and major depressive episode prevalence estimates arising from the different approaches to assessing DSM-IV criterion between two national surveys. Differences in the assessment of impairment strongly influence manic or hypomanic classification within the NESARC. Compared to multiple imputation estimates (19.7% [95% CI: 19.3-20.1]) which treat depressed mood and anhedonia as separate symptoms, symptom assessment in the NESARC substantially underestimates major depressive episode prevalence (16.9% [95% CI: 16.1-17.6]).
The second research objective examined self-reported cannabis use as a risk factor for incident manic symptoms, bipolar spectrum disorders (including manic and hypomanic episodes) and SCID-based recalibrated BD I and II. Cannabis use risk was assessed in the population as a whole and in sub-populations defined by age, substance abuse/dependence status, and family history. Among those reporting no lifetime major depressive or manic symptoms at baseline, self-reported past-year cannabis use was associated with increased odds of an incident week of extremely elevated or irritable mood accompanied by at least two manic episode criterion B symptoms (adj. OR 1.69, 95% CI: 1.08-2.65, p=.02) over the three year follow-up period. Among adults (ages 26 to 45) >=1 reported use(s) of cannabis per week was associated with incident manic or hypomanic episodes (adjusted OR 2.52, 95% CI: 1.32-4.80, p=.006). Among those endorsing no major depressive symptoms, substance abuse/dependence, or anti-social traits in their first degree relatives, past year cannabis use is associated with increased risk for incident bipolar spectrum disorders (adjusted OR 2.27, 95% CI: 1.01-5.10, p=.05) and CIDI recalibrated BD I and II (adjusted OR 5.49, 95% CI: 1.38-21.9, p=.02). Past year cannabis use risk for DSM-IV manic or hypomanic episodes among those aged 26 to 45 is concentrated in those with a baseline history of a substance use disorder (adj. OR 2.00, 95% CI: 1.10-3.66, p=.02) as compared to those with no such history (adj. OR 1.87, 95% CI: 0.49-7.21, p=.36).
The third research objective of this dissertation was a sensitivity analysis using externally-predicted categorized exposures and continuous cannabis use propensities. The sensitivity analysis found evidence of exposure misclassification. Exposures defined by external propensity scores had improved cross-sectional association with bipolar spectrum disorders compared to reported use when both were compared to an external standard. No significant risk estimates were found for categorized predicted cannabis use among groups that were previously found to have significant risk from reported exposure. However, among adults 18 to 45 years of age with no manic or major depressive symptoms at baseline, past year cannabis use propensity (as a log transformed continuous measure) was associated with incident manic or hypomanic episodes (adj. OR 1.49, 95% CI: 1.10-2.03, p=.01). Elevated risk for high cannabis use propensity (>=1 use/week in the past year) was also found in this same group (adj. OR 1.33, 95% CI: 1.03-1.72, p=.03). Among those with no reported history of depression, substance abuse/dependence, or anti-social traits among their first-degree relatives, propensity for past year cannabis use (adj. OR 1.61, 95% CI: 1.11-2.32, p=.01) and propensity for >=1 use/week of cannabis in the past year (adj. OR 1.38, 95% CI: 1.03-1.85, p=.03) were associated with incident manic or hypomanic episodes. Among those without a substance use history at baseline, propensity for past year cannabis use (adj. OR 1.63, 95% CI: 1.33-1.55, p=1 use/week of cannabis in the past year (adj. OR 1.54, 95% CI: 1.26-1.88, p
The findings of the first aim support the conclusion that the AUDADIS substantially under-estimated lifetime major depressive episode prevalence compared to an imputed estimate that treated anhedonia and depressed mood as separate and concurrent MDE symptoms. The operationalization of impairment for manic disorders in both the AUDADIS and CIDI strongly influences case identification, with the CIDI having suppressed manic and hypomanic prevalence estimates. Evidence was found supporting the conclusion that self-reported cannabis use is a significant risk factor for incident bipolar spectrum outcomes within subpopulations in a nationally representative cohort. A sensitivity analysis finds evidence that supports the conclusion that increasing cannabis use propensity is associated with increased risk of bipolar spectrum outcomes within population subgroups, with the greatest increased risk among those with the lowest innate risk. Under-reporting of illicit substance use is a major limitation in this dissertation; further study is needed with improved exposure measures.
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Healy, Helen G. "Cognition and emotion in bipolar disorder." Thesis, Bangor University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417222.
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Ang, Oon Sim. "Modeling of double heterojunction bipolar transistors." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29458.
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A one-dimensional analytical model in the Ebers-Moll formulation of a graded base double
heterojunction bipolar transistor (DHBT) is developed and used to examine the effects of base grading, the emitter-base barrier and the base-collector barrier on the d.c. current gain, offset voltage and the high frequency performance of a N — Al[formula omitted]Ga₁[formula omitted]As/p — Al[formula omitted]Ga₁[formula omitted]As/N — Al[formula omitted]Ga₁[formula omitted]As DHBTs. Recombination processes considered in the space charge regions and the neutral regions are: Shockley-Read-Hall, radiative and Auger. The trade-off between base-grading, which reduces the base current, and the neutral base recombination, which is brought about by varying the aluminium the junctions, results in an optimum aluminium mole fraction profile regarding the d.c. current gain. For high frequency performance, a similar trade-off to that of the d.c. situation
exists. In this case, the important manifestation of the increased collector-base barrier height is an increase in the base transit time. The aluminium mole fraction profile which optimises the unity gain cut-off frequency, f[formula omitted], and the unity power gain cut-off frequency, f[formula omitted], is established. DHBTs which are symmetrical, both in aluminium mole fraction and doping concentration profiles, are shown to have low common-emitter offset voltages, V[formula omitted],[formula omitted]. Base-grading reduces V[formula omitted],[formula omitted] in devices in which the difference between the emitter and collector aluminium mole fraction is < 0.1; otherwise, V[formula omitted],[formula omitted] increases as base-grading increases. The model is also used to examine the performance of a N-Al[formula omitted]Ga₁[formula omitted]As/p-In[formula omitted]Ga₁[formula omitted]As/N-Al[formula omitted]Ga₁[formula omitted]As DHBT. It is shown that radiative and Auger recombination limit the d.c. current gain in this device.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Grozeva, Detelina. "Copy number variation in bipolar disorder." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/54197/.
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A plethora of studies have suggested that copy number variation in the human genome is extensive and may play an important role in susceptibility to disease, including neuropsychiatric disorders such as schizophrenia and autism. The possible involvement of copy number variants (CNVs) in bipolar disorder has received little attention to date. This PhD thesis describes work that sought to determine whether large (≥ 100 kb) and rare (with frequency ≤ 1%) CNVs are associated with susceptibility to bipolar disorder and to make comparisons with previous findings in schizophrenia. In order to do that, a genome-wide survey of large and rare CNVs in a case-control sample using a high-density microarray was performed. 1697 cases of bipolar disorder and 2806 non-psychiatric controls were genotyped using Affymetrix 500K array set. Subsequently, the copy number data were inferred and analysed. The burden of CNVs in bipolar disorder was not increased compared with controls. Furthermore, CNVs > 1 Mb were found with statistically significant lower rate in bipolar disorder as compared to schizophrenia. In addition, CNV loci previously implicated in the aetiology of schizophrenia were not more common in cases with bipolar disorder. The main observation was that large and rare CNVs do not have a major effect in the susceptibility to bipolar disorder. In addition, it was noted that bipolar disorder and schizophrenia differ with respect to CNV burden in general and specific CNVs in particular. As the same CNVs implicated in schizophrenia, have been observed in autism and mental retardation, and not in bipolar disorder, it is reasonable to postulate that CNVs could be a specific genetic factor for a predisposition to disorders with stronger neurodevelopmental component than bipolar disorder. This study has provided one of the first glimpses of the possible involvement of copy number variation in the susceptibility to bipolar disorder.
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McAuley, Erica Zoe Prince of Wales Medical Research Institute Faculty of Medicine UNSW. "Identification of bipolar disorder susceptibility genes." Publisher:University of New South Wales. Prince of Wales Medical Research Institute, 2009. http://handle.unsw.edu.au/1959.4/43690.
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Bipolar affective disorder is a severe mood disorder, which is characterised by episodes of mania and depression. The aetiology of bipolar disorder remains elusive, with little known about the underlying biological, anatomical, or biochemical effects. However, family, twin and adoption studies provide evidence for a strong genetic component to the disorder. Due to the high heritability, familial clustering, and common population prevalence of the illness, molecular genetic studies can be implemented to identify bipolar disorder susceptibility genes. This thesis investigated the candidate gene serotonin 2A receptor (HTR2A), which lay within a region on chromosome 13q14 previously identified by bipolar disorder genome-wide linkage scans. Significant association was found with bipolar disorder and a SNP within intron 2 of HTR2A in an Australian case-control cohort. Haplotype association analysis identified a 5-SNP protective haplotype within HTR2A. Conducting a new genome-wide linkage scan on 35 Australian bipolar disorder pedigrees found significant evidence for linkage on chromosome 15q25-26. Subsequent fine-mapping of the region verified the linkage peak with a significant maximum multipoint LOD score of 4.58. Haplotype analysis, based on pedigree-specific, identical-by-descent allele sharing, supported the location of a bipolar susceptibility gene within a 6.2Mb confidence interval. The candidate gene sialyltransferase 8B (ST8SIA2), which had previously shown association with SNPs within the genes promoter region and schizophrenia in two independent Asian cohorts, lies within the chromosome 15q25-26 locus. Failing to replicate the association found with these specific SNPs, and without finding association with two additional SNPs in an upstream conserved putative regulatory region, a fine-mapping association study was conducted across the entire 6.2Mb interval. The strongest association signals were observed at SNPs 16kb upstream from and within the fourth intron of ST8SIA2. A specific bipolar disorder risk haplotype was identified for ST8SIA2, and this was also observed to be over-represented in a cohort of Australian schizophrenia cases. This finding suggests that the ST8SIA2 gene, for which strong developmental regulation was observed, may be a shared susceptibility gene for both bipolar disorder and schizophrenia. In summary, this thesis has provided evidence identifying both HTR2A and ST8SIA2 as bipolar disorder susceptibility genes.
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Gradinaru, Diana. "High-voltage RF silicon bipolar transistor." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0001/MQ45631.pdf.
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Bass, Nicholas James. "Genetic association studies of bipolar disorder." Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1444258/.
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Bipolar disorder is a common and serious mental illness. The occurrence of mania is central to the diagnosis, but affected individuals typically also suffer episodes of depression. The results of family, twin and adoption studies argue convincingly for genetic susceptibility to bipolar disorder. Linkage studies conducted at the Molecular Psychiatry Laboratory, UCL have previously implicated the regions 12q24, 21q22, lq42 and 11 pi4- 15 as harbouring susceptibly loci for bipolar disorder. In this thesis I report fine mapping of the 12q24, 21q22 and lq42 regions by linkage disequilibrium methods, employing a case-control design. For the llpl4-15 region association with the candidate gene BDNF was tested. I also present attempts to replicate findings of association at the genes DAOA and COMT, located in regions implicated by meta-analysis of the linkage data. I have attempted to put these investigations in context, necessitating consideration of the conceptual developmental of bipolar disorder, the classical techniques for assessing the genetic contribution to aetiology, and mapping strategies. Fine mapping of the UCL linkage regions implicated two novel susceptibility loci and provided support for two previously identified loci. Association of multiple markers within a 180 kb region of 12q24.3 was found, implicating Slynar and LOC387895. Association was also found with two markers in the more centromeric gene P2RX7, previously implicated in a Canadian sample. Multiple associated markers were found on 21q22.3. Two candidate genes - C21orf29 and TRPM2 - were identified from this region. Initial efforts to fine map the lq42 region suggested the involvement of the previously implicated DISCI gene. However association was only found with a single marker. Although haplotypic association was found with BDNF, the complex structure of the microsatellite marker hindered interpretation of the results. Partial replication of the association with DAOA was achieved but the involvement of COMT was not supported.
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Babiker, Nathan T. "Reward-oriented processes in bipolar disorder." Thesis, University of Hull, 2008. http://hydra.hull.ac.uk/resources/hull:1591.
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There is thought to be a link between characteristic reward-oriented processes in bipolar disorder and dysregulation in the behavioural activation system (BAS). This study aimed to assess differences between bipolar and healthy control individuals in their response to reward, failure and a reasoning task sensitive to data-gathering biases. Participants were 25 adults with bipolar I disorder and 25 healthy controls. Measures of sensitivity to reward and failure were collected during the first task (Go task), which included visual analogue ratings of mood and success expectancy, reaction time of button-pressing, and the difficulty level set by the participant. There were no significant differences between groups following reward feedback or failure feedback on the Go task. Results from the second task showed that bipolar individuals needed less data than controls before making a decision on the emotionally-neutral, difficult version of the task. The results are discussed in relation to current trends in bipolar research.
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Hsu, C. W. "Advanced insulated gate bipolar transistor technologies." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604680.
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The thesis aims at investigating the state-of-the-art The Insulated Gate Bipolar Transistor (IGBT) technologies and exploring novel device concepts based on the IGBT core in order to enhance device performance and functionality. First, a novel double gate IGBT (DG-IGBT) is demonstrated by numerical simulations and experimental verifications. The new device features a low-grain pnp transistor and an embedded thyristor to enhance the carrier concentration near the emitter side and thus improves the on-state performance. Second, a new IGBT structure featuring N+ islands in the buffer layer to control the on-state carrier density in the drift region is proposed. The new technique allows a precise control of the trade-off between on-state voltage drop and turn-off energy losses by simply adjusting the width and spacing of N+ islands on the mask (at the layout level rather than process level). Furthermore, the N+ islands technique can be used to produce a series of products with different specifications by only changing the mask layout. Finally, a new reverse-conducting IGBT (RC-IGBT) with an embedded thyristor is reported in this dissertation for the first time. The thyristor operates similarly to an anti-parallel diode in its on-state and therefore it can release stored energy in the inductive load when the IGBT turns off. The new RC-IGBT shows a “snapback-free” characteristic due to the existence of the thyristor. In addition, coupled with the N+ islands structures proposed before, the on-state performance and switching speed of the IGBT and thyristor can be optimised according to the requirements of the specific application.
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Briggs, P. J. "Transport effects in heterojunction bipolar transistors." Thesis, University of East Anglia, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361427.
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Thompson, Jill Maria. "Cognitive architecture in euthymic bipolar disorder." Thesis, University of Newcastle Upon Tyne, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417560.
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El-Badri, Selim Mohamed. "Neurobiological changes in bipolar affective disorder." Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242439.
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Azoff, Eitan Michael. "Computer modelling of heterojunction bipolar transistors." Thesis, University of Sheffield, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420290.
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Liu, Chin Pang. "Optoelectronic mixing in heterojunction bipolar transistors." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312033.
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Zamdmer, Noah. "Hot-electron degradation of bipolar transistors." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/36023.
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Atkinson, Juan Pablo. "Cost model for bipolar plate manufacture." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71625.
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Thesis (MScEng)--Stellenbosch University, 2012.ENGLISH ABSTRACT: This thesis gives a cost model for the manufacture of bipolar plates in South Africa. The methods for the manufacture considered are machining, using a micro-milling machine, and compression moulding. The focus of this thesis is on compression moulding. Details of the work done towards developing and validating the models are described, and then the cost models are discussed in detail. The results of the analysis done using the cost model is given with attention paid to the effect of changing design parameters, such as channel size and flow field area, and of the cost of production for both methods over various production volumes. The thesis concludes that compression moulding becomes the better option for production volumes greater than 324 bipolar plates, with a cost that eventually reaches close to R140 per plate for high enough production volumes (over 5000). The cost to produce 1000 plates using compression moulding is estimated at R294 per plate. An increase of the channel size gives a small reduction in the total cost, while the increase in cost with an increase in flow field area is large.
AFRIKAANSE OPSOMMING: Hierdie tesis gee 'n koste-model vir die vervaardiging van bipolêre plate in Suid- Afrika. Die vervaardigingsmetodes wat oorweeg word, is masjinering deur 'n mikro-freesmasjien en persvorming. Die fokus van hierdie tesis is op persvorming. Die besonderhede van die ontwikkeling en validering van die modelle word beskryf, en daarna word die modelle in besonderhede beskryf. Die resultate van 'n analise wat met die koste-model gedoen is, word daarna gegee, met die oorweging van die verandering van ontwerp-parameters soos die vloeikanaalgrootte en vloeiveld-area, en van die koste van vervaardiging vir beide metodes vir verskeie produksievolumes. Die tesis kom tot die slotsom dat persvorming die voorkeurproses is vir produksievolumes groter as 324 bipolêre plate, met 'n koste wat tot naastenby R140 per plaat daal vir hoë produksievolumes (meer as 5000). Die koste om 1000 plate met persvorming te maak, word op R294 per plaat beraam. 'n Toename in kanaalgrootte gee 'n klein vermindering in die totale koste, terwyl die toename in koste groot is wanneer die vloeiveld-area toeneem.
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Abreu, Tânia Alexandra Coelho de. "Perturbação afectiva bipolar e ciclos circadianos." Master's thesis, Faculdade de Medicina da Universidade do Porto, 2010. http://hdl.handle.net/10216/61044.
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