Adolescence is a time of great changes, a time where experimentation and exploration is expected and when the values of authority figures are examined and challenged. Adolescents will experiment and push the boundaries of all aspects of their life in order to find their own place and identity in a world that has changed its expectations of them. Use of drugs is one of the ways that they do this. Australian adolescents grow up in a society where alcohol and tobacco is an acceptable part of daily life. Their use of drugs is at least on par with and in some cases exceeds that of the general population. The overall goals of this research were to gain more information on drug use of Australian adolescents, using existing data sets. This research examined, using a number of different age groups, the differences in adolescent drug use between urban and rural Australia for lifetime use, use in the last year and use in the last month using the 2002 edition of the Australian School Student Alcohol and Drug (ASSAD) survey series in conjunction with the 2001 National Drug Strategy Household Survey (NDSHS). It also used these data sets to investigate differences between indigenous adolescents and non-Indigenous adolescents and whether there were any differences in adolescent drug use across socio-economic status groups. Four hypotheses were developed. The first was that rural adolescents are more likely than urban adolescents to use licit drugs and the second was that urban adolescents are more likely than rural adolescents to use illicit drugs. Thirdly, that Indigenous adolescents are more likely than non-Indigenous adolescents to use both licit and illicit drugs and the fourth was that adolescents from low socio-economic status (SES) groups are more likely than adolescents from high SES groups to use licit and illicit substances. The data offered little support for any of the hypotheses. The hypothesis on rural adolescents being more likely to use licit drugs was supported by the ASSAD surveydata but not the NDSHS. All other hypotheses were not supported by either of the data sets. While there are aspects of the information from the two data sets that are contradictory making it difficult to prove or disprove the hypotheses formulated for this research, they highlighted a number of aspects of adolescent drug use. The first of these is that this research supports the premise that rural adolescent drug use rates are converging with urban drug use rates for younger adolescents. It also highlighted that there are a large number of rural school students who are using alcohol and cannabis. The ASSAD data also confirmed other Australian research showing that Indigenous adolescents are less likely than their non-Indigenous counterparts to use alcohol. Both data sets confirmed previous research by indicating that adolescents from the high SES groups are more likely than their counterparts in the lower SES groups to consume alcohol. Further investigation is needed to find out why the data sets did not substantiate each other and to gain further insight into the consumption of alcohol by Indigenous adolescents and adolescents from the higher socio-economic status groups. Increasing the samples of Indigenous people in both of the data sets and lobbying the Australian Bureau of Statistics to increase their sample for the Indigenous Social Survey to include 12-14 year olds should give more information on Indigenous adolescents that could be used in research and prevention activities.

Este estudo apresenta o desenvolvimento da metodologia de extração em fase sólida e separação em cromatográfica líquida acoplada a espectrometria de massas em sequencia, SPE-LC-MS/MS, para a determinação de 21 (vinte e um) fármacos pertencentes a diferentes classes terapeuticas, 1 (uma) droga de abuso e seu principal metabólito, em amostras de água superficial. A separação cromatográfica foi otimizada estudando o desempenho de fases estacionárias e fases móvies. A quantificação dos compostos selecionados foi realizada com a ionização por eletronebulização (electrospray ionization- ESI) e o espectrômetro de massas operando no modo de Monitoramento de Múltiplas Reações (Multiplas Reaction Monitoring- MRM). A validação da metodologia proposta foi realizada utilizando os parâmetros de seletividade, efeito de matriz, faixa de trabalho, linearidade, limites de detecção (LD) e quantificação (LQ), precisão, exatidão, recuperação e robustez. A validação da metodologia permitiu a sua aplicação na avaliação da distribuição dos 23 compostos selecionados, nas águas da represa Guarapiranga, um dos principais sistemas produtor de água potável da Região Metropolitana de São Paulo (RMSP). A presença desses poluentes nos ambientes aquáticos é proveniente da liberação direta do esgoto urbano das habitações do seu entorno, como consequência do precário sistema de saneamento básico. As águas da represa Guarapiranga foram avaliadas em 14 (quatorze) locais estrategicamente escolhidos e amostradas durante 3 (três) campanhas de coleta de amostra (agosto de 2011, setembro de 2012 e abril de 2013). Nessas amostras foram quantificados acetaminofeno (9,6 - 254 ng L-1), atenolol (8,5 177 ng L-1), benzoilegonina (7,9 139 ng L-1), cafeína (27 27386 ng L-1), carbamazepina (12 358 ng L-1), clortalidona (9,4 35 ng L-1), cocaína (12,8 2650 ng L-1), diclofenaco (8 35 ng L-1), enalapril (20 ng L-1), losartana (6,7 114 ng L-1) e valsartana (9,7 - 47 ng L-1). O ponto de coleta denominado de GU103-12 (23°4188.5S 46°4467.3W) foi a região que apresentou os valores mais elevados quanto ao nível de concentração dos compostos avaliados e ao índice de risco integrado de poluição química aquática (Integrated Risk Index of Chemical Aquatic Pollution IRICAP). O estudo também foi realizado em amostras de água de reservatórios das Unidades de Gerenciamento de Recursos Hídricos (UGRHI) 5 e 6 do Estado de São Paulo. Os resultados demonstraram que o uso e a ocupação do solo influenciam diretamente na qualidade da água dos reservatórios, evidenciando a necessidade de implementar melhorias no sistema de coleta de esgoto e de ocupação irregular para evitar a contaminação e o descarte inadequado em ambientes aquáticos. / This study presents the development of the methodology of solid phase extraction and liquid chromatography - tandem mass spectrometry, SPE-LC-MS/MS, for the determination of 21 (twenty one) pharmaceuticals belonging to different therapeutic groups, 1 (one) illicit drug and its major metabolite, in surface water samples. The chromatographic separation was optimized by studying the performance of different stationary and mobile phases. Quantitation of selected compounds was performed by electrospray ionization (ESI) and the mass spectrometer operating in a multiple reaction monitoring (MRM) mode. The validation of the proposed methodology was performed using the parameters of selectivity, matrix effect, dynamic range, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, recovery and robustness. The validation of methodology allowed to apply the methodology in the evaluation of the distribution of the 23 (twenty one) selected compounds, in Guarapiranga Dam waters, an of the major producer system of drinking water of the Metropolitan Region of São Paulo (MRSP). The presence of these pollutants in aquatic environments is from the direct release of urban sewage from the homes of your surroundings, as a result of poor sanitation system. The waters of Guarapiranga dam were evaluated in 14 (fourteen) locations strategically chosen and sampled in 3 (three) campaigns of sample collection (August 2011, September 2012 and April 2013). In these samples were quantified acetaminophen (9.6 - 254 ng L-1), atenolol (8.5 - 177 ng L-1), benzoylegonine (7.9 - 139 ng L-1), caffeine (27 - 27386 ng L-1) carbamazepine (12 - 358 ng L-1), chlorthalidone (9.4 - 35 ng L-1), cocaine (12.8 - 2560 ng L-1), diclofenac (8 - 36 ng L-1), enalapril (20 ng L-1), losartan (6.7 - 114 ng L-1) and valsartan (9.7 - 47 ng L-1). The sample siting GU103-12 (23°4188.5S 46°4467.3W) was the region with the highest values in the level of concentration of the target compounds and the integrated risk index of chemical aquatic pollution (IRICAP). The study was also conducted on water samples from reservoirs of the UGRHI (Unit of Water Resources Management) 5 and 6, State o São Paulo. The results showed that the use and occupation of land directly influence the reservoir water quality highlighting the need to implement improvements in sewage collection system and illegal occupation to prevent contamination and the improper disposal in aquatic environments.

In this work, we focus on enhancing the efficacy of predictive modeling in operational management decision making in two different settings: Essay 1 focuses on demand forecasting for the companies and the second study utilizes longitudinal data to analyze the illicit drug seizure and overdose deaths in the United States. In Essay 1, we utilize an operational system (newsvendor model) to evaluate the forecast method outcome and provide guidelines for forecast method (the exponential smoothing model) performance assessment and judgmental adjustments. To assess the forecast outcome, we consider not only the common forecast error minimization approach but also the profit maximization at the end of the forecast horizon. Including profit in our assessment enables us to determine if error minimization always results in maximum profit. We also look at the different levels of profit margin to analyze their impact on the forecasting method performance. Our study also investigates how different demand patterns influence maximizing the forecasting method performance. Our study shows that the exponential smoothing model family has a better performance in high-profit products, and the rate of decrease in performance versus demand uncertainty is higher in a stationary demand environment.In the second essay, we focus on illicit drug overdose death rate. Illicit drug overdose deaths are the leading cause of injury death in the United States. In 2017, overdose death reached the highest ever recorded level (70,237), and statistics show that it is a growing problem. The age adjusted rate of drug overdose deaths in 2017 (21.7 per 100,000) is 9.6% higher than the rate in 2016 (19.8 per 100,000) (U. S. Drug Enforcement Administration, 2018, p. V). Also, Marijuana consumption among youth has increased since 2009. The magnitude of the illegal drug trade and its resulting problems have led the government to produce large and comprehensive datasets on a variety of phenomena relating to illicit drugs. In this study, we utilize these datasets to examine how marijuana usage among youth influence excessive drug usage. We measure excessive drug usage in terms of drug overdose death rate per state. Our study shows that illegal marijuana consumption increases excessive drug use. Also, we analyze the pattern of most frequently seized illicit drugs and compare it with drugs that are most frequently involved in a drug overdose death. We further our analysis to study seizure patterns across layers of heroin and cocaine supply chain across states. This analysis reveals that most active layers of the heroin supply chain in the American market are retailers and wholesalers, while multi-kilo traffickers are the most active players in the cocaine supply chain. In summary, the studies in this dissertation explore the use of analytical, descriptive, and predictive models to detect patterns to improve efficacy and initiate better operational management decision making.

With the epidemiological transition, causes of death shifted from communicable to non-communicable diseases (NCDs) and life expectancy increased, as these NCD deaths occurred later in life. However, in the United States, over the past years, life expectancy has been stagnating or decreasing despite decreasing NCD mortality rates. Analyses of the most important underlying causes of death with increasing premature mortality reveal that psychoactive substance use played a crucial role for these increases. Furthermore, it can be shown, that a high proportion of the increased premature mortality and decreased life expectancies happened in lower socio-economic strata. Substance use policies should thus focus on lowering the gap between substance-attributable mortality in higher versus lower socioeconomic strata.

Aim: To examine prospectively over a period of 4 years the profile of cannabis dependence and the risk of specific dependence criteria in a community sample of adolescents. Methods: A representative community sample of 2446 young adults aged 14–24 years at baseline was followed up over a period of 4 years. Frequency of use measures and of criteria for DSM-IV dependence were assessed by standardized diagnostic interview measures (CIDI). To explore the nature of this association, frequency of use and concomitant use of other psychoactive substances was considered. Results: 30% of the sample were cannabis users. Among all users 35% met at least one dependence criterion. Most frequently reported dependence criteria among all users were withdrawal (17%), tolerance (15%), loss of control (14%) and continued use despite a health problem (13%). Even without concomitant use of other illicit drugs, 22% of low frequency users and 81% of high frequency users met at least one dependence criterion. Symptom patterns were similar in high and low frequency users. The occurrence of a dependence syndrome or of specific dependence criteria could not be attributed to the use of other illicit drugs or to comorbid nicotine and alcohol dependence. Conclusions: Regular cannabis use in adolescence is associated with the development of a dependence syndrome. This association cannot be explained by the concomitant use of other illicit substances or by comorbid nicotine and alcohol dependence.

Il existe peu de recherches, surtout en francophonie, qui portent une attention au point de vue des parents qui consomment des drogues sur leurs expériences personnelles en lien avec la prise en charge de leurs enfants par les services de protection de la jeunesse. Cette étude cherche à contribuer à la connaissance en la matière, en donnant une voix aux mères qui consomment des drogues illicites, des voix essentielles pour le développement et la bonification des services de soutien qui leur sont destinés. Ancrée dans deux cadres théoriques, la théorie de la reconnaissance et la théorie de l’intersectionnalité, cette recherche se focalise sur l’expérience, les stratégies et les logiques d’action des mères qui consomment des drogues illicites ayant des enfants pris en charge par les services de protection de la jeunesse. S’inscrivant dans une méthodologie qualitative et phénémonologique, neuf entretiens ont été menés avec des mères en s’inspirant de l’outil du récit de vie de Bertaux (2006). L’analyse des récits permet de faire émerger trois types de logiques d’action mises en place par les mères dans leur recherche de reconnaissance avec les services de protection de la jeunesse au Québec : une logique d’action d’indignation, une logique d’action de collaboration et une logique d’action de distanciation. Les résultats mettent en lumière l’articulation entre les expériences et les rapports que vivent ces mères avec la protection de la jeunesse et les stratégies qu’elles adoptent pour préserver leur dignité. Elle souligne l’importance des expériences de reconnaissance et de mépris dans la construction de leurs logiques d’action. Les récits des mères rencontrées et les résultats de cette recherche témoignent de l’impact que le mépris peut avoir sur leurs vies et de la grande nécessité de penser et d’agir à travers le prisme de la reconnaissance. Sur la base de ces résultats, quatre recommandations d’approches d’intervention sont évoquées comme étant prometteuses pour le renforcement de la reconnaissance et du pouvoir d’agir des mères qui consomment des drogues illicites. / There is little research, especially in the French language, that pays attention to the point of view of parents who use drugs and their personal experiences in relation to Child Protection Services (CPS). This study seeks to contribute to knowledge in this area, by giving a voice to mothers who use illicit drugs. These voices are essential for the development and improvement of the support services intended for these mothers and their children. Anchored in two theoretical frameworks, the theory of recognition and the theory of intersectionality, this research focuses on the experience, strategies, and logics of action of mothers who use illicit drugs with children taken into care by CPS. As part of a qualitative and phenemonological methodology, nine interviews, based on the life story tool of Bertaux (2006), were conducted with mothers who use illicit drugs. The analysis of these accounts reveals three types of logics of action put in place by mothers in their search for recognition with the youth protection services: a logic of indignation, a logic of collaboration and a logic of distancing. The results highlight the articulation between the experiences and relationships these mothers have with CPS and the strategies they adopt to preserve their dignity. It underlines the importance of experiences of recognition and contempt in the construction of their logics of action. The stories of these mothers and the results of this research testify to the impact that contempt can have on their lives and the great need to think and act through the prism of recognition. Based on these findings, four recommendations for intervention are invoked as being promising for strengthening recognition and empowerment of mothers who use illicit drugs.