No description available.

<p>  </p> <p>The major concern about vehicle crashes has led to a great amount of research on the topic in the road safety area. Nevertheless, real-world crash data collection periods are often extensive and they result in a great delay in improving safety. Therefore, surrogate measures of safety, such as traffic conflicts, are considered for safety management.</p> <p>The definition of a traffic conflict has evolved over the course of half a century. One of the current definitions encompasses a failure-based road event that inevitably results in a crash if no evasive action is taken by involved road users. This counterfactual concept was validated with specific road events datasets, including rear-end events and vehicle-bicycle encounters. However, observing conflicts for an extended period is still a major difficulty. For example, a LIDAR-based technique applicable to intersections can collect conflict data for a relatively short period of several days. The LiDAR-collected data are then converted to the corresponding expected crash frequency during the observation period, which eventually must be expanded to the corresponding annual value. The conversion step has not been sufficiently addressed in the past research. Thus, an important task of estimating the annual expected crash frequency based on a short-term estimate remains unanswered. Addressing this need is the research objectives and contribution of this study.</p> <p>Advanced statistical methods allow developing models to estimate expected crash frequencies for annual and short periods. The ratio of such two estimates is defined as an expansion factor in this study. This thesis presents the modeling effort and its results for different types of crashes at signalized and unsignalized intersections in Indiana. Traditional and emerging data, such as traffic volume, speed, road characteristics, weather, and other features were collected and assembled at randomly selected 194 intersections. Then, they were used to estimate the logistic models of hourly crash probability. The models were then utilized to calculate expansion factors for a specific intersection.to evaluate the method.</p>

There are many reports indicating the presence of emerging contaminants such as: estrogen hormones, 1,4-dioxane and perfluoro-octanoic acids in the natural environment. Estrogen hormones are considered important emerging class of contaminants due to their endocrine disrupting effects. These compounds are invariably found in the environment originating mostly from natural sources. Trace concentrations of estrogen hormones (low µg/L concentrations) have been detected in municipal wastewater treatment plants and observed in receiving water bodies. 1,4-Dioxane (C4H8O2) is used as an organic solvent and solvent stabilizer numerous in chemical processes. The United States Environmental Protection Agency (US-EPA) has recognized 1,4-dioxane as a toxic chemical and a possible human carcinogen. 1,4-dioxane has been detected as a contaminant in the natural environment, drinking water supplies, superfund sites, public groundwater sources in the United States, Canada and Japan at concentrations greater than the permissible standards. Perfluorinated chemicals such as perfluoro-octanoic acid (PFOA) and perfluorooctane-sulfonate (PFOS) have been manufactured for use in a variety of industrial and consumer applications. Due to their environmental persistence, PFOAs have been detected in surface waters at a number of locations at concentrations ranging from pg/L to ng/L. Elevated concentrations of PFOAs have been measured in surface and ground waters near specific point sources. Through this project, successful attempts have been made for the destruction of emerging contaminants using ultrasound. This study deals with the optimization of various process parameters for the destruction of estrogen hormones. The influence of process parameters such as power density, reactor geometry, power intensity, ultrasound amplitude, and external mixing was investigated. Artificial neural network (ANN) approach was used to describe the interactions between optimized parameters. The important findings obtained in the present work for the optimized estrogen degradation can help tackle the challenges of scale up such as operational optimization and energy consumption. The effect of process conditions such as pH and presence of oxidizing agents on the ultrasonic destruction of 1,4-dioxane and PFOA was studied. Acidic conditions favored the destruction of both the compounds. The presence of activated sulfate radicals enhanced the reaction rate kinetics. An innovative technology using electric potential and ultrasound for the removal organic contaminants was developed. The existence of organic contaminants in ionic form under certain process conditions has led to the development of this technology. Applying a low electric potential across the probe enhances the mass transfer of the contaminants into effective reaction zone, thereby enhancing the total destruction. A two-fold increase in the reaction rates was observed. This study shows ultrasound as an efficient and effective treatment technology for the destruction of emerging contaminants. / Civil Engineering

This study is an examination of how delayed transitions to adulthood have influenced the period of active offending for low-level offenders. This research has implications for the criminal justice system, its policies directed toward dealing with low-level offenders, and the branch of criminological research that explores offender taxonomies and the relationship between age and crime. Arnett's (2000) theory argues that emerging adulthood is a new stage of the life course, neither adolescence nor young adulthood, that is the result of several areas of social change. During this stage, despite having reached biological maturity, individuals postpone the achievement of adult commitments and responsibilities. Combined with a lack of traditional social bonds and a failure to meet various life course turning points, these individuals exist in a state of "arrested adolescence." During this state, many have the opportunity to explore their identities in areas such as romantic relationships and work. These explorations have also been theorized to include deviant and criminal behavior. While Arnett's theory has been cited extensively, only a handful of studies have attempted to empirically test its tenets with regard to delinquency or criminality. Prior research in life course criminology has established several different offender typologies linked to the impact of transitions to adult roles as turning points (for most) away from criminality (see for example, Laub & Sampson, 2003; Moffitt, Caspi, Rutter, & Silva, 2001). The present study answered the following research question; "Does the emerging adulthood stage of the life course influence offending trajectories?" Specifically, it predicted that emerging adulthood has delayed transitions to adult roles for those in their early to mid twenties. As a result, there is a higher rate of low-level, non-violent crimes such as vandalism and disorderly conduct for certain (arrested adolescent) offenders. Defined as a low-level criminal offender between the ages of 18 and 25, the arrested adolescent offender has yet to successfully transition to adult social roles (e.g., marriage, parenthood) that inhibit deviance and increase traditional social bonding. If Arnett's theory of emerging adulthood is correct, arrested adolescent offenders will continue to commit low-level offenses at rates typically seen in adolescents. Beyond examining this core question, this dissertation also extends Arnett's theory in three significant ways: by utilizing the theory to explicitly examine crime and deviance, clarifying how emerging adulthood influences offending, and by exploring whether the delay of turning points (e.g., marriage, parenting) and changes in social bonds (e.g., religious participation, bonds with family) influences offending. These questions were addressed using three waves of data from the National Longitudinal Study of Adolescent Health (Udry, 1998). At each wave of data, measures of crime, arrested adolescent vs. life course persistent offending (minor vs. serious) and drug use, arrested adolescent vs. life course persistent drug use (minor vs. serious) were examined as dependent variables. These indicators were selected from the crime and delinquency scales available in all three waves of the National Longitudinal Study of Adolescent Health. Arrested adolescent (minor) crimes consist of low-level offenses such as drunken and disorderly conduct and shoplifting. Arrested adolescent (minor) drug use is defined as using "softer" drugs such as alcohol and marijuana. Life course persistent (serious) crime is defined as more severe types of offenses such as burglary and selling drugs. Life course persistent (serious) drug use is defined as the frequent use of "harsher" drugs such as cocaine. These data were analyzed cross-sectionally using both bivariate and multivariate analyses. At waves 1 and 2, bivariate relationships between indicators of arrested adolescence and offending allowed an exploration of how these factors relate to offending during late childhood and adolescence. At wave 3, when members of the sample are in the emerging adulthood stage of the life course, a series of regression models examined how measures of arrested adolescence related to offending. The findings of this dissertation support the idea that many traditional turning points and social bonds do operate effectively during emerging adulthood. Turning points including education and hours worked were found to predict arrested adolescent offending. Social bonds including religious participation, economic stability, and parental attachment also were significant predictors of arrested adolescent offending. However, many of the other turning points, such as having children and military service, and social bonds, such as job satisfaction, that were found to be effective at reducing offending in other samples were not significant. Results suggest that specific turning points and social bonds are relevant factors in reducing offending for emerging adults. These findings, taken as a whole, suggest that emerging adulthood is a factor influencing offending. Emerging adulthood has the potential to alter patterns of offending over the life course, and there is a need for prospective longitudinal studies to examine the long-term influence of emerging adulthood on life course offending. / Criminal Justice

Objective: To examine the impact of treatment outcome and treatment condition (Cognitive-behavioral therapy, CBT; Sertraline, SRT; COMB, CBT and SRT; Placebo) for youth treated for anxiety disorders on global and domain-specific functioning across a 3 to 12 year, naturalistic follow-up. Method: A subset (319) of 488 families from the Child/Adolescent Anxiety Multimodal Study (CAMS; Walkup et al., 2008) participated in an average of 3.38 assessments during the follow-up period. All youth met criteria for a principal anxiety disorder pretreatment. Growth curve modeling examined the impact of treatment outcomes (response/remission) and treatment condition on global functioning, global and domain- specific impairment, and life satisfaction across the follow-up period. Logistic regression explored the impact of treatment response and condition on low frequency events (arrests/convictions) and educational achievement (high school graduation/college enrollment). Results: Growth curve analyses revealed that treatment responders/remitters demonstrated better global functioning, increased life satisfaction, and decreased overall impairment at their first follow-up assessment (growth curve mean intercept). The positive effect of treatment response on life satisfaction, but not global functioning or overall impairment, attenuated across the follow-up period. Treatment response also predicted decreased academic impairment at first follow-up. Participants in the COMB condition demonstrated improved functional trajectories with regards to family life and academic grade-point average. CBT participants demonstrated a greater decline in overall impairment and problems with self-care/independence across the follow-up. Treatment response and condition did not predict legal outcomes, school attendance, high school graduation, college attendance, occupational outcomes, or social/peer relationships. Conclusion: Response to early intervention is associated with improved overall functioning, as well as functioning within specific domains (academics) 3 to 12 years posttreatment. Treatment type differentially predicted functional trajectories. Findings support the positive impact of pediatric anxiety treatment on functioning during adolescence and emerging adulthood. / Psychology

There are many reports indicating the presence of various emerging contaminants (ECs) in treated wastewater and other water sources. The detection of such contaminants in the environment and the ability of these contaminants to pose potential threats to the environment at very low concentrations have led to a need for more efficient treatment technologies. Cyclodextrins (CDs) have gained significant interest as an alternative adsorbent for water and wastewater treatment because of their unique physico-chemical characteristics and excellent selectivity towards organic compounds. The property of CD to form inclusion complexes with various molecules through host-guest interactions has made it a useful compound for the removal of a number of contaminants from water and wastewater. The overall goal of the study is to identify and develop a novel adsorbent for the removal of ECs of interest. The specific objectives are a) to synthesize various beta-cyclodextrin (BCD) based adsorbents by coating BCD onto different supports such as silica, filter paper, iron oxide, and zeolite, b) to perform batch and column experiments using the developed adsorbents, c) to evaluate the performance of the adsorbents in different water matrices such as MQ water, simulated wastewater in presence of humic acid, and real municipal wastewater, d) to study the regeneration potential of the adsorbents. In this research, various (BCD) based hybrid adsorbents were synthesized and their performances were evaluated based on the removal of selected ECs. At first, chemically bonded BCD onto silica particles as hybrid adsorbents were synthesized by using crosslinking agents and copolymers. Three different methods were used to synthesize 14 different BCD coated silica adsorbents. The adsorbent prepared by reacting BCD with hexamethylene diisocyanate (HMDI) as crosslinking agent and dimethyl sulfoxide (DMSO) as solvent showed best results in removing the ECs studied. The adsorbent showed more than 95% removal of 17β-estradiol (in single component) and more than 90% of most of the estrogens (mixture of 12), more than 99% of perfluorooctanoic acid (PFOA) (in single component) and more than 90% of most of the PFCs (mixture of 10), and a maximum of 90% removal in case of BPA. The adsorption capacity of the developed adsorbent was observed to be higher for the removal of 17β-estradiol and PFOA than that of commercially available activated carbon (F400) in MQ water. In order to represent the real environmental scenario, further batch experiments were conducted for the removal of two PFCs (PFOA and PFOS (perfluorooctane sulfonic acid)), 17β-estradiol, and BPA at environmentally relevant concentrations from wastewater. The adsorbent was effective in removing the ECs that were spiked in the secondary effluent of a municipal wastewater treatment plant. Furthermore, the adsorbent was successfully regenerated with methanol over four cycles without significant loss in its adsorption capacity for the removal of PFOA and estrogens. Ozonation as an alternative method of regeneration was also used and the process was also very effective in regenerating the adsorbent over seven successive cycles for the removal of BPA and 17β-estradiol. The characterization of the adsorbents using FTIR, TGA, and TEM confirmed the coating of BCD onto silica particles. The TGA results showed high thermal stability of the adsorbent (upto 300oC). As an alternative to chemical impregnation, another method of synthesis was developed where various BCD based hybrid adsorbents were synthesized by physically impregnating hydroxypropyl BCD (hpBCD) polymer onto three different supports: iron oxides, zeolite, and filter paper. The hpBCD impregnated filter papers were synthesized by solvent evaporation method and different adsorbents were synthesized by varying the polymer loadings. The polymer loading was optimized based on the performance of the modified (polymer impregnated) filter paper in terms of its filtration capacity as well as adsorption capacity to remove PFOA and BPA. The magnetic adsorbent was prepared by mixing hpBCD polymer with iron oxide (Fe3O4) particles. It was observed that by increasing the mixing time of the support (Fe3O4) with the polymer from 48 to 96 hr, the adsorption capacity of the adsorbent (hpBCD polymer coated Fe3O4) could be significantly enhanced. The same approach was also used to synthesize hpBCD polymer coated zeolite adsorbent and both adsorbents (hpBCD/zeolite and hpBCD/Fe3O4) were effective in removing the selected ECs from MQ water, simulated water, and wastewater. / Civil Engineering

Objectives: We investigated the prevalence of substance use disorders among emerging adults and quantified the extent to which emerging adults, compared to young adults, are at increased odds for substance use disorders. Methods: Data come from the 2012 Canadian Community Health Survey – Mental Health (CCHS-MH). Respondents were 15–39 years of age (n=9228) and were categorized as: early emerging adults (15-22 years); late emerging adults (23-29 years); and, young adults (30-39 years). Substance use disorders (alcohol or drug abuse/dependence) were measured using the Composite International Diagnostic Interview 3.0. The prevalence of substance use disorders was compared across age groups using design-based χ2 analyses. Odds ratios (OR) and 95% confidence intervals (CI) were computed from logistic regression models adjusting for sociodemographic and health covariates. All analyses were weighted to maintain representativeness of the study sample to the Canadian population. Results: The prevalence of alcohol use disorder was 8.0%, 6.6%, and 2.7% for early emerging adults, late emerging adults, and young adults respectively. For drug use disorder, the prevalence was 6.4%, 3.6%, and 1.3%. Compared to young adults, early and late emerging adults were more likely to report substance use disorders (p<0.01). The prevalence of drug use disorder was higher among early versus late emerging adults (χ2=119.8, p=0.01). Among all age groups, males were more likely to report alcohol or drug use disorders (p≤0.01 for all). After covariate adjustment, early and late emerging adults had greater odds of reporting alcohol (OR=3.2, 95% CI=2.2-4.9 and OR=2.4, 95% CI=1.6-3.4, respectively) or drug (OR=4.2, 95% CI=2.5-7.0 and OR=2.5, 95% CI=1.6-4.1, respectively) use disorders compared to young adults. Conclusion: Emerging adulthood represents an important developmental period in which individuals are at increased odds of reporting substance use disorders. This finding has implications for the provision of screening and treatment of substance use disorders as these individuals transition from the pediatric to adult healthcare system. / Thesis / Master of Health Sciences (MSc)

Background: The transition into emerging adulthood is a major developmental period in one’s life in which rapid declines in physical activity (PA) are documented. While many emerging adults possess intentions to engage in regular PA, evidence suggests acting on these intentions represents a significant challenge. Obtaining a deeper understanding of the factors associated with the process of translating emerging adult’s PA intentions into action may be integral in building a healthier adult population. The purpose of the study was to investigate the effects of two potential moderators of the PA intention-behaviour relationship: goal conflict and trait self-control, in a sample of emerging adults. Methods: The study sample was comprised of 132 participants (Mage = 17.80 ± 0.46; 64% female) drawn from a larger prospective cohort study (ADAPT Study). All participants completed two online questionnaires, approximately four weeks apart. Measures of PA intention strength, goal conflict and trait self-control were assessed at time 1. At time 2, participants completed a measure of self-reported moderate-to-vigorous physical activity (MVPA) engagement. Four moderation analyses were performed to assess the independent and combined effects of goal conflict and trait self-control on the PA intention-behaviour relationship. Results: Across all moderation analyses, the main effect of intention strength was significant (p < 0.001), providing support for the necessary role it plays in PA behaviour. However, the main effects of goal-conflict and trait self-control were not found to be significant, along with all interaction effects tested. Correlational analyses revealed intention strength (r = 0.346, p < .001) and goal-conflict (r = -0.236, p < 0.05) were significantly correlated with MVPA, however trait self-control (r = 0.048) was not. Conclusion: Although results showed a modest intention-PA relationship, the hypothesized moderating effects of goal conflict and self-control were not supported. While the subjective perception of one’s self-control ability did not moderate the intention-behaviour relationship, future research should explore the interaction between goal conflict and self-control further using more objective measures, or in combination with self-regulation strategies such as action and coping planning. Additionally, goal prioritization may be an important factor to consider when investigating the effect of goal conflict on PA and the intention-PA relationship. / Thesis / Master of Science (MSc)

Relatively little research has focused on the positive adjustment of emerging adult adoptees (Palacios & Brodzinsky, 2010). Given the developmental context of emerging adulthood (Arnett, 2000), it is important to select a measure of adjustment that reflects the increased ambiguity seen in this time period. The present study aims to develop and validate a measure of relational competence, or competence in one’s closest relationship regardless of relationship type (i.e., romantic vs. nonromantic). This measure will be created by adapting the Romantic Competence Interview, a measure of romantic competence previously used with emerging adults (Shulman, Davila, & Shachar-Shapira, 2011). Participants included 162 emerging adult adoptees who were recruited as part of a larger longitudinal study (Grotevant, McRoy, Wrobel, & Ayers-Lopez, 2013). Indicators of relational competence were selected from measures of intimacy maturity coded from interviews in which participants discussed their self-identified closest relationship (White, Speisman, Costos, Kelly, & Bartis, 1984). Confirmatory factor analysis showed that the proposed model of relational competence was a good fit to the data and that this model was invariant across relationship type and gender. No differences in relational competence scores were found by relationship type or by gender

Lesbian, gay, bisexual, transgender, questioning, intersex, and queer (LGBTQIQ) adults are more likely to report experiences of complex trauma, and have detrimental mental health effects as a result, when compared to cisgender, heterosexual adults. However, LGBTQIQ adults have excellent capacity for resilience. In this phenomenological investigation, I explored the lived experiences of resilient LGBTQIQ emerging adults (N = 11) who have histories of complex trauma. Five themes emerged as a result of this study, including (a) abuse and neglect, (b) emotional experiences during and after trauma, (c) connections are essential, (d) getting through hard times, and (e) struggles in the counseling process. The results indicated implications for counselors and counselor educators to better address the experiences of complex trauma and identify resilience in LGBTQIQ emerging adults. Recommendations are provided to counselors and counselor educators for integrating knowledge and actions into their counseling, teaching, and supervision practices, as well as for parents and caregivers, teachers and school personnel, and policymakers.