Upgrade of the ALICE Inner Tracking System

The Inner Tracking System (ITS) is the key ALICE detector for the study of heavy flavour production at LHC. Heavy flavor can be studied via the identification of short-lived hadrons containing heavy quarks which have a mean proper decay length in the order of 100-300 $\mu$m. To accomplish this task, the ITS is composed of six cylindrical layers of silicon detectors (two pixel, two drift and two strip) with a radial coverage from 3.9 to 43 cm and a material budget of 1.1% X0 per layer. %In particular, the properties of the two innermost layers define the ITS performance in measuring the displaced vertex of such short-lived particles. In order to enhance the ALICE physics capabilities, and, in particular, the tracking performance for heavy-flavour detection, the possibility of an ITS upgrade has been studied in great detail. It will make use of the spectacular progress made in the field of imaging sensors over the last ten years as well as the possibility to install a smaller radius beampipe. The upgraded detector will have greatly improved features in terms of: the impact parameter resolution, standalone tracking efficiency at low $p_{t}$, momentum resolution and readout capabilities. The Conceptual Design Report, which covers the design and performance requirements, the upgrade options, as well as the necessary R&D efforts, was made public in September 2012. An intensive R&D program has been launched to review the different technological options under consideration. The new detector should be ready to be installed during the long LHC shutdown period scheduled in 2017-2018.Comment: 6 pages, 9 figures PIXEL2012 - International Workshop on Semiconductor Pixel Detectors for Particles and Imagin

Are behavioral problems in childhood and adolescence associated with bipolar disorder in early adulthood?

Several recent studies have found an association between conduct problems and bipolar disorder in adolescents. However, prospective studies are rare and most do not apply multivariable analysis strategies to control for important variables (e.g. socio-demographics). The aim of this study was to test the association between certain conduct problems and bipolar disorders. The sample consisted of 591 adolescents (male and female) representative for 2,600 persons from the Canton of Zurich in Switzerland. Data were prospectively collected through an interviewing procedure, with the first screening taking place at the age of 19-20. The incidence rate was computed using sampling weights, and risk factors of bipolar II disorder were estimated using a multivariable logistic regression model. The 9-year incidence rate of bipolar II disorder in the canton of Zurich was 8.4% (n=65). Adolescents and children showing behavior such as repeated running away from home and physical fighting were 2.6-3.5 times more likely to experience a bipolar II disorder than those with no indication of conduct problems. Sensitivity analysis showed that the conduct problems were not the result of low socio-economic statu

Internet-based Self-Assessment after the Tsunami: lessons learned

BACKGROUND: In the aftermath of the Tsunami disaster in 2004, an online psychological self-assessment (ONSET) was developed and made available by the University of Zurich in order to provide an online screening instrument for Tsunami victims to test if they were traumatized and in need of mental health care. The objective of the study was to report the lessons learnt that were made using an Internet-based, self-screening instrument after a large-scale disaster and to discuss its outreach and usefulness. METHODS: Users of the online self-assessment decided after finishing the procedure whether their dataset could be used for quality control and scientific evaluation Their answers were stored anonymously only if they consented (which was the case in 88% of the sample), stratified analyses according to level of exposure were conducted. RESULTS: A total of 2,914 adult users gave their consent for analysis of the screenings. Almost three quarter of the sample filled out the ONSET questionnaire within the first four weeks. Forty-one percent of the users reported direct exposure to the Tsunami disaster. Users who were injured by the Tsunami and users who reported dead or injured family members showed the highest degree of PTSD symptoms. CONCLUSION: ONSET was used by a large number of subjects who thought to be affected by the catastrophe in order to help them decide if they needed to see a mental health professional. Furthermore, men more frequently accessed the instrument than women, indicating that Internet-based testing facilitates reaching out to a different group of people than "ordinary" public mental health strategies

Exposure to the tsunami disaster, PTSD symptoms and increased substance use – an Internet based survey of male and female residents of Switzerland

BACKGROUND: After the tsunami disaster in the Indian Ocean basin an Internet based self-screening test was made available in order to facilitate contact with mental health services. Although primarily designed for surviving Swiss tourists as well as relatives and acquaintances of the victims, the screening instrument was open to anyone who felt psychologically affected by this disaster. The aim of this study was to evaluate the influences between self-declared increased substance use in the aftermath of the tsunami disaster, trauma exposure and current PTSD symptoms. METHODS: One section of the screening covered addiction related behavior. We analyzed the relationship between increased substance use, the level of PTSD symptoms and trauma exposure using multivariable logistic regression with substance use as the dependent variable. Included in the study were only subjects who reported being residents of Switzerland and the analyses were stratified by gender in order to control for possible socio-cultural or gender differences in the use of psychotropic substances. RESULTS: In women PTSD symptoms and degree of exposure enlarged the odds of increased alcohol, pharmaceuticals and cannabis use significantly. In men the relationship was more specific: PTSD symptoms and degree of exposure only enlarged the odds of increased pharmaceutical consumption significantly. Increases in alcohol, cannabis and tobacco use were only significantly associated with the degree of PTSD symptoms. CONCLUSION: The tsunami was associated with increased substance use. This study not only replicates earlier findings but also suggests for a gender specificity of post-traumatic substance use increase

Predicting violent infractions in a Swiss state penitentiary: A replication study of the PCL-R in a population of sex and violent offenders

BACKGROUND: Research conducted with forensic psychiatric patients found moderate correlations between violence in institutions and psychopathy. It is unclear though, whether the PCL-R is an accurate instrument for predicting aggressive behavior in prisons. Results seem to indicate that the instrument is better suited for predicting verbal rather than physical aggression of prison inmates. METHODS: PCL-R scores were assessed for a sample of 113 imprisoned sex and violent offenders in Switzerland. Logistic regression analyses were used to estimate physical and verbal aggression as a function of the PCL-R sum score. Additionally, stratified analyses were conducted for Factor 1 and 2. Infractions were analyzed as to their motives and consequences. RESULTS: The mean score of the PCL-R was 12 points. Neither the relationship between physical aggression and the sum score of the PCL-R, nor the relationship between physical aggression and either of the two factors of the PCL-R were significant. Both the sum score and Factor 1 predicted the occurrence of verbal aggression (AUC=0.70 and 0.69), while Factor 2 did not. CONCLUSION: Possible explanations are discussed for the weak relationship between PCL-R scores and physically aggressive behavior during imprisonment. Some authors have discussed whether the low base rate of violent infractions can be considered an explanation for the non-significant relation between PCL-R-score and violence. The base rate in this study, however, with 27%, was not low. It is proposed that the distinction between reactive and instrumental motives of institutional violence must be considered when examining the usefulness of the PCL-R in predicting in-prison physical aggressive behavior

Analytical solutions for space charge fields in TPC drift volumes

At high particle rates and high multiplicities, Time Projection Chambers can suffer from field distortions due to slow moving ions that accumulate within the drift volume. These variations modify the electron trajectory along the drift path, affecting the tracking performance of the detector. In order to calculate the track distortions due to an arbitrary space charge distribution in a TPC, novel representations of the Green's function for a TPC-like geometry were worked out. This analytical approach permits accurate predictions of track distortions due to an arbitrary space charge distribution (by solving the Langevin equation) as well as the possibility to benchmark common numerical methods to calculate such space charge fields. (C) 2011 Elsevier B.V. All rights reserved

Posttraumatic stress disorder in a Swiss offender population

Questions under study: Various studies have repeatedly shown an increased prevalence for Posttraumatic Stress Disorder (PTSD) in delinquents when compared with the general population. Lifetime prevalence varies between 33% and 36%, and point prevalence between 17% and 21%. The aim of this study was to examine whether these findings are applicable to offenders detained in SwitzerlandMethods: The sample consisted of 86 offenders. In order to control for over-reporting of traumatic life events three sub-samples (remand, sentenced/inpatient and sentenced/outpatient) administered by the Office of Corrections of the Canton of Zurich were examined. PTSD was diagnosed using the Posttraumatic Diagnostic Scale (PDS), a self-rating instrument for diagnosing PTSD according to the Diagnostic and Statistical Manual of Mental Disorders, Version IV (DSM-IV).Results: Point prevalence of PTSD was conservatively estimated at 27%. The three sub-samples did not differ in the prevalence of PTSD when adjusted for potential demographic differences. Seventy-five percent of the subjects had experienced at least one traumatic event that matched the criteria for a traumatic event according to the DSMIV. The Median number of traumatising life events according to the PDS was four in the examined sample.Conclusions: In this sample of male prisoners in Switzerland the prevalence of current PTSD was comparable to other international studies. The limitations and implications of these findings were discussed.publishe