Control based on discrete-event models of continuous systems

A control stategy based on a possibly non-deterministic discrete-event model of a continuous system is proposed. Such a model can arise when a continuous plant is to be supervised by some computer program which uses discrete state information. The discrete-event representation of the continuous system will often be non-deterministic and therefore difficult to control. The contol method proposed exploits the fact that the original system is continuous. An example shows the possibilities of the control method.</p

Hypomania Checklist-32 - cross-validation of shorter versions screening for bipolar disorders in an epidemiological study.

Self-reports such as Hypomania Checklist (HCL-32) can be used to enhance recognition of bipolar disorders, but they are often too long and only validated in clinical samples. The objectives of this study are therefore to test whether (i) the HCL-32 can be used for screening in the community and (ii) whether two previously suggested shorter versions would do as well. Data stemmed from the CoLaus|PsyColaus, a prospective cohort study which included randomly selected residents aged 35-66 years from an urban area. Participants underwent semistructured interviews to assess DSM-IV disorders and 1712 of them completed the HCL-32. Forty individuals (2.3%) were diagnosed as having BD. Compared to others, participants with BD scored significantly higher on the HCL-32. The HCL-32 had a sensitivity of 0.78 and specificity of 0.68. Very similar figures were found for two previously proposed shorter versions with 16 and 20 items. The results of confirmatory factor analysis and item response theory (IRT) models supported the postulated two-factor structure for the three HCL versions. Despite the low base rate of BD in this sample, the screening properties of the HCL-32 remained almost as good. Importantly, two previously proposed shorter versions performed as well, suggesting that those could be used without losing essential information

The clinical trajectory of emerging bipolar disorder among the high-risk offspring of bipolar parents: current understanding and future considerations.

Relatively little is known about the onset of bipolar disorder, yet the early illness course is already associated with significant morbidity and mortality. Therefore, characterizing the bipolar illness trajectory is key to risk prediction and early intervention advancement. In this narrative review, we discuss key findings from prospective longitudinal studies of the high-risk offspring of bipolar parents and related meta-analyses that inform us about the clinical trajectory of emerging bipolar disorder. Challenges such as phenotypic and etiologic heterogeneity and the non-specificity of early symptoms and syndromes are highlighted. Implications of the findings for both research and clinical practice are discussed. Bipolar disorder in young people at familial risk does not typically onset with a hypomanic or manic episode. Rather the first activated episode is often preceded by years of impairing psychopathological states that vary over development and across emerging bipolar subtype. Taking heterogeneity into account and adopting a more comprehensive approach to diagnosis seems necessary to advance earlier identification and our understanding of the onset of bipolar disorder

The association between self-reported and clinically determined hypomanic symptoms and the onset of major mood disorders.

Hypomanic symptoms may be a useful predictor of mood disorder among young people at high risk for bipolar disorder. To determine whether hypomanic symptoms differentiate offspring of parents with bipolar disorder (high risk) and offspring of well parents (control) and predict the development of mood episodes. High-risk and control offspring were prospectively assessed using semi-structured clinical interviews annually and completed the Hypomania Checklist-32 Revised (HCL-32). Clinically significant sub-threshold hypomanic symptoms (CSHS) were coded. HCL-32 total and active or elated scores were higher in control compared with high-risk offspring, whereas 14% of high-risk and 0% of control offspring had CSHS. High-risk offspring with CSHS had a fivefold increased risk of developing recurrent major depression (P=0.0002). The median onset of CSHS in high-risk offspring was 16.4 (6-31) years and was before the onset of major mood episodes. CSHS are precursors to major mood episodes in high-risk offspring and could identify individuals at ultra-high risk for developing bipolar disorder. None. © The Royal College of Psychiatrists 2017. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) license

Externalizing disorders and substance use: empirically derived subtypes in a population-based sample of adults.

PURPOSE: Attention-deficit/hyperactivity disorder (ADHD), conduct disorder (CD), and oppositional defiant disorder (ODD) are common externalizing disorders of childhood. The common effects of these disorders on substance abuse need further investigation. The current study investigated the joint clusters of childhood/adolescence ADHD, CD, and ODD, and their influence on substance abuse/dependence in a population-based sample of adults. METHODS: The data were drawn from the PsyCoLaus study (n = 3,720) conducted in Lausanne, Switzerland. The population-based sample included 238 subjects meeting criteria for ADHD/ODD/CD diagnoses before the age of 15. Latent class analyses (LCA) were performed to derive comorbidity subtypes, which were subsequently characterized with respect to psychosocial correlates and substance use. RESULTS: The best fit in LCAs was achieved with three latent classes: an ADHD subtype (35.7 %); an externalizing multimorbid subtype (33.6 %) involving ODD, ADHD, and CD; and a third subtype with CD (30.7 %). The CD subtype showed the highest association with substance use. Apart from this, the externalizing multimorbid subtype was also significantly linked to substance use. The ADHD subtype had only elevated frequencies for alcohol dependence in comparison with subjects that had no history of ADHD, ODD, and CD during childhood or adolescence. Finally, important interactions between subtypes and sex were observed with regard to substance use. CONCLUSIONS: This study provides evidence showing that subtyping the externalizing disorders, ADHD, ODD and CD, along their comorbidity patterns leads to important differences regarding substance use. This could have implications for the etiology, prevention, and treatment of substance use disorders

Individuals' quality of life linked to major life events, perceived social support, and personality traits.

PURPOSE: The aim of this study was to investigate the relationship between major recent life events that occurred during the last 5 years, social and personal resources, and subjective quality of life (QoL). METHODS: A total of 1801 participants from the general population (CoLaus/PsyCoLaus study) completed the Life Events Questionnaire, the Social Support Questionnaire, the NEO Five-Factor Inventory Revised, and the Manchester Short Assessment of Quality of Life. RESULTS: Major life events were modestly associated with the QoL (about 5 % of the explained variance). However, QoL was significantly related to perceived social support and personality traits (about 37 % of the explained variance). Particularly, perceived social support, extraversion and conscientiousness personality dimensions were positively linked to life satisfaction, whereas a high level of neuroticism was negatively associated with QoL. CONCLUSION: This study highlights the negative but temporary association between critical events and QoL. However, a combination of high conscientiousness and extraversion, and positive social support may explain better variances for a high-perceived QoL

Posttraumatic stress avoidance symptoms as mediators in the development of alcohol use disorders after exposure to childhood sexual abuse in a Swiss community sample.

This study examined the role of posttraumatic stress disorder (PTSD) symptoms of re-experience, avoidance, and hyperarousal in the relationship between different types of trauma and alcohol use disorders (AUD). We used data from 731 trauma-exposed individuals who participated in the first wave of the PsyCoLaus-study. Trauma characteristics were assessed relatively to the occurrence of lifetime PTSD symptoms and AUD. The results suggest that lifetime and childhood sexual abuse as well as overall childhood trauma were directly linked to AUD and PTSD symptoms, in particular to avoidance symptoms. From single symptom clusters PTSD avoidance was found to specifically mediate the trauma-AUD pathway. Both childhood and sexual trauma strongly contribute to the comorbidity of PTSD and AUD and avoidance-type symptoms appear to play a central role in maintaining this association. Hence, the alleviation of avoidance symptoms might be an important target for therapeutic intervention among victims of sexual abuse before specific addiction treatment is initiated