Development of open models and tools for seismic risk assessment: application to Portugal

The exponential growth of the world population has led to an increase of settlements often located in areas prone to natural disasters, including earthquakes. Consequently, despite the important advances in the field of natural catastrophes modelling and risk mitigation actions, the overall human losses have continued to increase and unprecedented economic losses have been registered. In the research work presented herein, various areas of earthquake engineering and seismology are thoroughly investigated, and a case study application for mainland Portugal is performed. Seismic risk assessment is a critical link in the reduction of casualties and damages due to earthquakes. Recognition of this relation has led to a rapid rise in demand for accurate, reliable and flexible numerical tools and software. In the present work, an open-source platform for seismic hazard and risk assessment is developed. This software is capable of computing the distribution of losses or damage for an earthquake scenario (deterministic event-based) or earthquake losses due to all the possible seismic events that might occur within a region for a given interval of time (probabilistic event-based). This effort has been developed following an open and transparent philosophy and therefore, it is available to any individual or institution. The estimation of the seismic risk depends mainly on three components: seismic hazard, exposure and vulnerability. The latter component assumes special importance, as by intervening with appropriate retrofitting solutions, it may be possible to decrease directly the seismic risk. The employment of analytical methodologies is fundamental in the assessment of structural vulnerability, particularly in regions where post-earthquake building damage might not be available. Several common methodologies are investigated, and conclusions are yielded regarding the method that can provide an optimal balance between accuracy and computational effort. In addition, a simplified approach based on the displacement-based earthquake loss assessment (DBELA) is proposed, which allows for the rapid estimation of fragility curves, considering a wide spectrum of uncertainties. A novel vulnerability model for the reinforced concrete building stock in Portugal is proposed in this work, using statistical information collected from hundreds of real buildings. An analytical approach based on nonlinear time history analysis is adopted and the impact of a set of key parameters investigated, including the damage state criteria and the chosen intensity measure type. A comprehensive review of previous studies that contributed to the understanding of the seismic hazard and risk for Portugal is presented. An existing seismic source model was employed with recently proposed attenuation models to calculate probabilistic seismic hazard throughout the territory. The latter results are combined with information from the 2011 Building Census and the aforementioned vulnerability model to estimate economic loss maps for a return period of 475 years. These losses are disaggregated across the different building typologies and conclusions are yielded regarding the type of construction more vulnerable to seismic activity.

Shear behaviour of steel-fibre-reinforced concrete simply supported beams

The structural behaviour of steel-fibre-reinforced concrete beams was studied using non-linear finite-element analysis and existing experimental data. The work aim was to examine the potential of using steel fibres to reduce the amount of conventional transverse steel reinforcement without compromising ductility and strength requirements set out in design codes. To achieve this, the spacing between shear links was increased while steel fibres were added as a substitute. Parametric studies were subsequently carried out and comparisons were also made with BS EN 1992-1-1 predictions. It was concluded that the addition of steel fibres enhanced the load-carrying capacity and also altered the failure mode from a brittle shear mode to a flexural ductile one. The provision of fibres also improved ductility. However, interestingly it was found that adding excessive amounts of fibres led to a less-ductile response. Overall, the study confirmed the potential for fibres to compensate for a reduction in conventional shear reinforcement.

Clustering of lifestyle risk behaviours among residents of forty deprived neighbourhoods in London: lessons for targeting public health interventions

Background Clustering of lifestyle risk behaviours is very important in predicting premature mortality. Understanding the extent to which risk behaviours are clustered in deprived communities is vital to most effectively target public health interventions. Methods We examined co-occurrence and associations between risk behaviours (smoking, alcohol consumption, poor diet, low physical activity and high sedentary time) reported by adults living in deprived London neighbourhoods. Associations between sociodemographic characteristics and clustered risk behaviours were examined. Latent class analysis was used to identify underlying clustering of behaviours. Results Over 90% of respondents reported at least one risk behaviour. Reporting specific risk behaviours predicted reporting of further risk behaviours. Latent class analyses revealed four underlying classes. Membership of a maximal risk behaviour class was more likely for young, white males who were unable to work. Conclusions Compared with recent national level analysis, there was a weaker relationship between education and clustering of behaviours and a very high prevalence of clustering of risk behaviours in those unable to work. Young, white men who report difficulty managing on income were at high risk of reporting multiple risk behaviours. These groups may be an important target for interventions to reduce premature mortality caused by multiple risk behaviours.

Changing patterns of first injection across key periods of the French Harm Reduction Policy: PrimInject, a cross sectional analysis

Background: Monitoring of emerging modes of drug consumption in France has identified new patterns of injection among youths with diverse social backgrounds, which may explain the persistence of high rates of hepatitis C virus infection. The circumstances surrounding the first injection have been poorly documented in the group of heavy drug users and in the context of the French opioid substitution treatment (OST) policy that provides expanded access to high-dosage buprenorphine (BHD). Methods: An Internet survey (Priminject) was conducted from October 2010 to March 2011 with French drug users. Four time periods were compared based on critical dates throughout the implementation of the Harm Reduction Policy in France. Results: Compared with drug users who injected for the first time prior to 1995, the aspects of drug use for users who recently injected for the first time were as follows: (1) experimentation with miscellaneous drugs before the first injection; (2) an older age at the time of first injection; (3) heroin as the drug of choice for an individual’s first injection, notwithstanding the increased usage of stimulant drugs; (4) BHD did not appear to be a pathway to injection; and (5) an increased number of users who injected their first time alone, without the help or presence of another individual. Conclusion: The PrimInject study showed that there is a group of injection drug users that is larger than the group of injection drug users observed in previous studies; therefore, it is necessary to diversify programs to reach the entire spectrum of high-risk users.

Comportamentos autolesivos em adolescentes : características epidemiológicas e análise de fatores psicopatológicos, temperamento efetivo e estratégias de coping

Tese de doutoramento, Medicina (Psiquiatria e Saúde Mental), Universidade de Lisboa, Faculdade de Medicina, 2014

Tensile behaviour of a structural adhesive at high temperatures by the extended finite element method

Component joining is typically performed by welding, fastening, or adhesive-bonding. For bonded aerospace applications, adhesives must withstand high-temperatures (200°C or above, depending on the application), which implies their mechanical characterization under identical conditions. The extended finite element method (XFEM) is an enhancement of the finite element method (FEM) that can be used for the strength prediction of bonded structures. This work proposes and validates damage laws for a thin layer of an epoxy adhesive at room temperature (RT), 100, 150, and 200°C using the XFEM. The fracture toughness (G Ic ) and maximum load ( ); in pure tensile loading were defined by testing double-cantilever beam (DCB) and bulk tensile specimens, respectively, which permitted building the damage laws for each temperature. The bulk test results revealed that decreased gradually with the temperature. On the other hand, the value of G Ic of the adhesive, extracted from the DCB data, was shown to be relatively insensitive to temperature up to the glass transition temperature (T g ), while above T g (at 200°C) a great reduction took place. The output of the DCB numerical simulations for the various temperatures showed a good agreement with the experimental results, which validated the obtained data for strength prediction of bonded joints in tension. By the obtained results, the XFEM proved to be an alternative for the accurate strength prediction of bonded structures.

Understanding the internet banking adoption by Portuguese customers - a unified theory of acceptance and use of technology and perceived risk application.

Trabalho de Projeto apresentado como requisito parcial para obtenção do grau de Mestre em Estatística e Gestão de Informação

Hipertensão arterial em adolescentes escolarizados da área de intervenção do Centro de Saúde de Queluz

RESUMO - A hipertensão arterial é uma das maiores causas de mortalidade e morbilidade mundial, sendo responsável por cerca de 7,1 milhões de mortes anualmente. A tensão arterial elevada no início da vida está associado a hipertensão na idade adulta, sendo a adolescência uma altura fundamental para modificar estilos de vida e comportamentos que possam diminuir a prevalência de hipertensão. Os dados existentes sobre a hipertensão arterial na adolescência em Portugal não são consistentes, mas parecem apontar para um aumento da prevalência. Entre Janeiro e Março de 2007 foi realizado um estudo descritivo e transversal, para determinar a prevalência de hipertensão dos alunos do 7º Ano das Escolas da área de intervenção do Centro de Saúde de Queluz. Foram avaliados sexo, idade, tensão arterial, perfil estato-ponderal, antecedentes familiares de hipertensão arterial e prática de exercício físico de 902 alunos. O estudo determinou uma taxa de prevalência de hipertensão arterial global de 25,3%, mais prevalente no sexo feminino (30,3%) do que no masculino (19,6%). Nos indivíduos com IMC superior a 25 kg/m2, foi encontrada uma prevalência de 50% de hipertensão sendo de apenas 21,2% nos com um perfil estato-poderal mais baixo. O Odds Ratio ajustado para raça, sexo, idade e turno (manhã/tarde) foi de 2,33 para indivíduos com um IMC superior a 25 kg/m2. Estes dados revelam a necessidade da implementação de medidas de prevenção da doença e promoção da saúde, tendo como objectivo a diminuição da prevalência deste factor de risco e das doenças que lhe estão associadas.

Essays in health economics: Volume-Outcome Effect, upcoding behaviour and the evaluation of a short-term intervention program

Evidence in the literature suggests a negative relationship between volume of medical procedures and mortality rates in the health care sector. In general, high-volume hospitals appear to achieve lower mortality rates, although considerable variation exists. However, most studies focus on US hospitals, which face different incentives than hospitals in a National Health Service (NHS). In order to add to the literature, this study aims to understand what happens in a NHS. Results reveal a statistically significant correlation between volume of procedures and better outcomes for the following medical procedures: cerebral infarction, respiratory infections, circulatory disorders with AMI, bowel procedures, cirrhosis, and hip and femur procedures. The effect is explained with the practice-makes-perfect hypothesis through static effects of scale with little evidence of learning-by-doing. The centralization of those medical procedures is recommended given that this policy would save a considerable number of lives (reduction of 12% in deaths for cerebral infarction).

A cross-sectional survey of attitudes to HIV risk and rapid HIV testing among clients of sex workers in Switzerland.

OBJECTIVES: To assess attitudes to HIV risk and acceptability of rapid HIV testing among clients of street-based female sex workers (FSW) in Lausanne, Switzerland, where HIV prevalence in the general population is 0.4%. METHODS: The authors conducted a cross-sectional study in the red light district of Lausanne for five nights in September of 2008, 2009 and 2010. Clients of FSW were invited to complete a questionnaire in the street assessing demographic characteristics, attitudes to HIV risk and HIV testing history. All clients interviewed were then offered anonymous finger stick rapid HIV testing in a van parked on-site. RESULTS: The authors interviewed 112, 127 and 79 clients in 2008, 2009 and 2010, respectively. All were men, average age 32-37 years old; 40-60% were in a stable relationship. History of unprotected sex was higher with non-commercial partners (33-50%) than with FSW (6-11%); 29-46% of clients had never undergone an HIV test. Anonymous rapid HIV testing was accepted by 45-50% of clients. Out of 109 HIV tests conducted during the three study periods, none was reactive. CONCLUSIONS: On-site HIV counselling and testing is acceptable among clients of FSW in this urban setting. These individuals represent an unquantified population, a proportion of which has an incomplete understanding of HIV risk in the face of high-risk behaviour, with implications for potential onward transmission to non-commercial sexual partners.

Excessive alcohol consumption in young men: is there an association with their earlier family situation? A baseline-analysis of the C-SURF-study (Cohort Study on Substance Use Risk Factors).

AIMS: To determine whether parental factors earlier in life (parenting, single parent family, parental substance use problem) are associated with patterns of alcohol consumption among young men in Switzerland. METHODS: This analysis of a population based sample from the Cohort Study on Substance Use Risk Factors (C-SURF) included 5,990 young men (mean age 19.51 years), all attending a mandatory recruitment process for the army. These conscripts reported on parental monitoring and rule-setting, parental behaviour and family structure. The alcohol use pattern was assessed through abstention, risky single occasion drinking (RSOD), volume drinking and dependence. Furthermore, the impact of age, family socio-economic status, educational level of the parents, language region and civil status was analysed. RESULTS: A parental substance use problem was positively associated with volume drinking and alcohol dependence in young Swiss men. Active parenting corresponded negatively with RSOD, volume drinking and alcohol dependence. Single parent family was not associated with a different alcohol consumption pattern compared to standard family. CONCLUSION: Parental influences earlier in life such as active parenting (monitoring, rule-setting and knowing the whereabouts) and perceived parental substance use problem are associated with alcohol drinking behaviour in young male adults. Therefore, health professionals should stress the importance of active parenting and parental substance use prevention in alcohol prevention strategies.

Risk perception, emotion regulation and impulsivity as predictors of risk behaviours among adolescents in Switzerland

The purpose of this study was to explore the frequency of risk behaviours among Swiss adolescents and their links with risk perception, impulsivity and emotion regulation abilities, operationalized with the concepts of alexithymia and emo- tional openness. We recruited 144 subjects (aged 14-20), who completed the Risk Involvement and Perception Scale (RIPS-R), the UPPS Impulsive Behavior Scale, the 20-item Toronto Alexithymia Scale (TAS-20), and the 20-item Dimensions of Openness to Emotional Experiences (DOE-20) questionnaire. Findings revealed that a greater perception of benefits and a higher level of sensation seeking were associated with more involvement in risk behaviours, which are essentially socially accepted behaviours. Notably, the path model indicated that the perception of benefits was a mediator in the relationship between sensation seeking and risk behaviours. The results add to the psychological understanding of factors associated with risk behaviours in adolescence. The limitations and implications of these results for developmental theories, research, and prevention are stated.

The role of self-presentation in adolescent health risk behaviours

Self-presentation has been identified as playing a key role in the perfonnance of various potentially hazardous health behaviours such as substance abuse, eating disorders and reckless behaviours (Leary, Tchividjian, & Kraxberger, 1994; Martin & Leary, 2001; Martin, Leary, & O'Brien, 2001). The present study investigated the role of selfpresentation on adolescent health-risk behaviours. Specifically, this study examined the prevalence of adolescent identified health-risk behaviours rooted in self-presentational motives in youths aged 13-18 years. The current study also identified the specific images associated with these behaviours desired by youth, and the targets of these behaviours. Also, the relationship between these behaviours, and several trait measures (social physique anxiety, public-self consciousness, fear of negative evaluations, selfpresentational efficacy) of self-presentation were examined. Finally, the gender differences in health risk behaviours and self-presentational concerns were examined. Participants in the present study were 96 adolescent students, 34 male and 62 female, recruited from various private schools across Southern Ontario. Students ranged in age from 13 to 18 years for both males (M age = 15.81 years, SD = 1.49) and females (M age = 14.89 years, SD = 1.17) and ranged from grades 8 through 13. Results of the current study suggested that Canadian adolescents between the ages of 13 and 18 years participated in health risk behaviours for self-presentational purposes. Drinking alcohol, skipping school, and performing stunts and dares were identified as the most common health risk behaviours performed for self-presentational purposes by both males and females. Appearing fun and cool were the most commonly reported desired images while appearing brave and mature were the least reported. The most desired target group cited was same sex friends, followed by other sex friends. Trait measures of self-presentational concerns identified females as being higher in public self-consciousness, and social physique anxiety than males. Males were found to be higher in self-presentational efficacy than females. The total number of health risk behaviours was predicted by selfpresentational efficacy and social physique anxiety for males, and social physique anxiety for females. Findings of the current study suggest that Canadian adolescents' health risk behaviours are rooted, in part, in self-presentational motives. Thus far, an educational approach to health interventions has been favoured and/or adopted by teachers, health promoters, and educators (Jessor, 1992). Implications of the current study suggest that although educational interventions are beneficial in presenting the associated risks with certain activities and/or behaviours, one reason this type of approach may be ineffective in changing adolescent behaviour over the long run is that it does not address the strong and prominent influences of interpersonal motives on health damaging behaviour. It is evident that social acceptance and public image are of importance to adolescents, and the desire to make the "right" impression and to achieve peer approval and acceptance often override health and safety concerns (Jessor, 1992). Thus, a self-presentational approach focusing on changing the images associated with the behaviours may be more successful at deterring adolescent health risk behaviours.

Stress, social support, and health risk behaviours as mediators of the forgiveness-health relation /

The mediating roles of stress, social support, and health risk behaviours in the relationships between dispositional forgiveness and mental and physical health were examined. Participants were 748 undergraduate students (554 women, 194 men) entering their first year of studies at Brock University. Participants, ranging in age from 17 to 25 years, completed the Brock University First Year Health Study and were provided monetary compensation. Dispositional forgiveness, stress, social support, health risk behaviours, mental health, and physical health were measured using self-report methods. The data were analyzed separately for women and men because there were significant mean differences on many of the study'S variables. Analyses revealed that the mediated relationships between dispositional forgiveness and health were generally stronger for women than men. Stress was the most robust mediator of the forgiveness-health relation for both women and men. The only health risk behaviour that mediated the forgivenesshealth relation was physical fitness and this result was found for women only. Social support mediated several of the relationships between forgiveness and health but not others. Results were discussed with reference to the literature on forgiveness and health. Several directions for future research were offered, such as conducting longitudinal research designs to assess the direction of causality better, investigating moderator variables of the forgiveness-health relation, and building models, which incorporate multiple mediators using structural equation modelling techniques.