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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Examining sucrose subjective response among individuals with opioid use disorder

Ochalek, Taylor Anne 01 January 2020 (has links)
Aims: Opioid use disorder (OUD) is associated with significant morbidity and mortality, and opioid agonist treatment (OAT) with methadone or buprenorphine represents the most efficacious treatment. However, data suggest that chronic administration of opioids may be associated with significant weight gain, possibly by altering an organism’s perception of and preference for sweet foods. The primary aim of this laboratory study was to rigorously examine sucrose subjective response among adults receiving OAT and a comparison sample without OUD. As secondary outcomes, we also sought to compare the groups on additional baseline characteristics that may influence subjective sucrose response and weight gain during treatment. Methods: Participants were 40 adults receiving treatment for OUD (OUD+) and a comparison sample of 40 adults without OUD (OUD-). All participants completed an initial screening visit that included questionnaires on eating behaviors, diet and nutrition, recent substance use, and measurement of body mass index. Eligible participants completed two, same-day outpatient laboratory sessions during which they sampled six experimenter-administered concentrations of sucrose solution (0, 0.1, 0.25, 0.5, 0.75, and 1.0M in distilled water) each three times under double-blind counterbalanced conditions. Following each exposure, participants rated the pleasantness and intensity of each sample using 100-point visual analog scales. Results: OUD+ participants rated sucrose solutions as less pleasant than OUD- participants (p<0.001). However, this effect was limited to the three lowest sucrose concentrations (0, 0.1, 0.25M), and at higher concentrations there were no group differences. There were no between-group differences on ratings of intensity (p=0.35). Given these baseline group differences in placebo (0M) responding, sucrose response was also examined in terms of change from baseline. In this analysis, there was a significant group effect, with a higher magnitude of change in pleasantness ratings and a lower magnitude of change in intensity ratings from 0M in OUD+ vs. OUD- participants (p’s<0.05). With regard to baseline characteristics that may influence sucrose response and eating behavior more generally, the OUD+ group had a higher prevalence of obesity, food insecurity, unhealthy eating behaviors, high sugar consumption, and nutrition knowledge deficits compared to the OUD- group (p’s<0.05). Conclusion: Data from preclinical and clinical research have suggested that opioid agonist medications may enhance subjective response to sweet flavors. In the present study, OUD+ participants exhibited a higher magnitude of change in pleasantness ratings from placebo compared to OUD- participants. However, this effect was largely driven by pronounced group differences in perceived pleasantness of essentially unsweet solutions. On the outcome of sucrose intensity, findings were more mixed with no consistent differences between OUD+ and OUD- participants. In contrast, group differences were far more pronounced in participants’ daily eating behaviors and nutrition knowledge, with OUD+ participants presenting with a consistently more severe profile. These data highlight the significant risk factors experienced by OUD+ individuals that extend beyond drug-related risks and may inform future scientific and clinical efforts to improve health outcomes in this vulnerable population.
242

On Structural Design of High-Speed Craft

Razola, Mikael January 2013 (has links)
The development in structural design and construction of high-speed craft has been extensive during the last decades. Environmental and economical issues have increased the need to develop more optimized structures, using new material concepts, to reduce weight and increase performance efficiency. However, both lack of, and limitations in design methodology, makes this a difficult task. In this thesis a methodological framework which enables detailed studies of the slamming loads and associated responses for high-speed planing craft in irregular waves is established. The slamming loads can either be formulated based on numerical simulations, or on experimental measurements and pressure distribution reconstruction. Structure responses are derived in the time-domain using finite element analysis. Statistical methods are used to determine design loads and lifetime extreme responses. The framework is applied to perform phenomenological studies of the slamming loading conditions for high-speed craft, and used to highlight and quantify the limitations in the prevailing semi-empirical method for design load determination with respect to slamming. A number of clarifications regarding the original derivation and the applicability of the prevailing semi-empirical method are presented. Finally, several potential improvements to the method are presented and the associated implications discussed. The long-term goal of the research project is to establish a method for direct calculation of loads and response for high-speed planing craft, which can enable design of truly efficient craft structures. The methodology and the results presented in this thesis are concluded to be important stepping-stones towards this goal. / <p>In page VII, Paper B is wrong title. The correct title is "Experiental Evaluation of Slamming Pressure Models Used in Structural Design of High-Speed Craft". QC 20130228</p>
243

Guarded and Unguarded Responses to Sentence Completion Tests Among Normal Adolescents and Juvenile Delinquents

Fazel, Mohammed K. 01 May 1967 (has links)
This study was designed to test the responses of a group of juvenile delinquests and a group of normal adolescents to a sentence completion test. The test used was a modified form of Sack's Sentence Completion test in two forms--form A, first person stems and form B, third person stems. The hypothesis to be tested were (1) people project more in the third person, (2) the normal projects more, and (3) there would be no difference in projection on neutral items. The results bear out the three hypothesis. The sex scale, however, was an exception. This may be due to the deficiency of items on this particular scale.
244

A Comparative Analysis of the Effects of Heterogeneous and Homogeneous Elementary School Grouping Practices on Selected Personality Variables

Swaner, Clarence D. 01 May 1962 (has links)
The relative advantages or disadvantages associated with the practice of grouping school children according to ability level has long been the subject of considerable discussion among educators. The general tendency has been for educators to divide into two camps: Those who expound the various merits of homogeneous grouping, and those who favor and support heterogeneous grouping practices, Less common, but acknowledged, are those educators who favor a combination of the two methods. Research dealing with the relative value of either method has usually been concerned with only one aspect of the problem--that of academic achievement. However, the.efforts of several investigators (Luchins and Luchins, 1948; Mathias, 1959; Tonsor, 1953) have suggested that different grouping practices may have differential effects upon the social adjustment and personality development of the pupil as well. As the total development of the child is of primary importance in the educational process, an investigation of the differential effects inherent in either of these methods of grouping would seem to be of value.
245

The effect of perceptual-motor training on maladaptive behaviors of emotionally disturbed children

Hall, Julia Frances 01 January 1970 (has links)
Twenty emotionally disturbed children between the ages of six and twelve from three agencies providing special treatment for behavioral or emotional problems were the subjects for this study. The subjects were divided into two major diagnostic categories, withdrawn and acing out, and then matched in pairs by age and diagnosis. One half of each pair was randomly assigned to the experimental condition and the remaining halves were assigned to the control condition. Both the experimental and control groups contained five withdrawn and five acting out subjects. Four experimenters were used, and each experimenter worked with two or four experimental children and their matched control subjects. The Purdue Perceptual-Motor Survey was administered to all the subjects prior to the experiment and behavior rating of maladaptive behaviors was obtained on each child from three adults who worked closely with the child. Using the methods outlined by Kephart and Radler in “Success Through Play”, the experimental subjects received perceptual-motor training for one-half hour three times a week for nine weeks. The control subjects received individual adult attention for the same amount of time as the training in the form of physical or quiet activities and games. At the end of the nine weeks the subjects were tested with the Purdue Perceptual-Motor Survey again and new behavior ratings also were obtained. The behavior scale was analyzed as a total score and then two subscores were obtained for anti-social and asocial behaviors. Analysis revealed that: 1) The experimental subjects’ perceptual-motor scores increased the most, especially among the withdrawn subjects; 2) The training had little effect on the maladaptive behaviors of the acting out subjects. The experimental acting out subjects improved behaviorally, but not significantly more than the control acting out subjects; 3) The training had a significant effect on the maladaptive behaviors of withdrawn children. The total behavior scores and the asocial behavior scores of the experimental withdrawn children improved; their anti-social scores changed very little. The subjects came from three agencies with different treatment philosophies. One agency was a public school with special classrooms for emotionally disturbed children which exclusively used behavior modification techniques. Another agency was a residential treatment center which was designed for a milieu therapy, where the children are removed from the home. The third agency was a semi-residential treatment center that used a combination of milieu therapy and behavior modification techniques, where the children return home for weekends. There were equal numbers of acting out, withdrawn, experimental and control subjects from any single agency. An analysis of the amount of behavioral improvement within each agency was performed which revealed that there was significantly more improvement among the subjects from the semi-residential treatment agency. It was concluded from this study that; perceptual-motor training increases the perceptual-motor abilities of emotionally disturbed children, especially those diagnosed as withdrawn, childhood schizophrenic and autistic; perceptual-motor training aids in reducing maladaptive behaviors in disturbed children diagnosed as withdrawn, childhood schizophrenic and autistic; perceptual-motor training may most effectively be used for emotionally disturbed children in conjunction with other forms of treatment.
246

A Comparison of Traditional Aggregated Data to a Comprehensive Second-by-Second Data Depiction in Functional Analysis Graphs

MacKelvie, Erin 01 January 2021 (has links)
Functional analyses (FAs) are an important component of treatment and the data gathered from FAs are often graphed in an aggregate or summary format, such as mean rate per session. Given the prevalence of undifferentiated analyses, it may be that this common method of data depiction is incomplete. In this paper, we compare the traditional aggregate method to a comprehensive second-by-second demonstration of the data including all appropriate and inappropriate responses emitted, as well as programmed and accidental antecedent and consequent variables, which may help further clarify the results of a functional analysis. We compared the functional analysis results of two participants when the data were depicted using the traditional rate aggregate method and depicted using a comprehensive second-by-second method. Although both rate and comprehensive second-by-second data depiction resulted in similar conclusions regarding the maintaining variables for the participants, comprehensive second-by-second data depiction allowed us to draw the conclusions in less time. Additional advantages and disadvantages of each method as it relates to efficiency, therapeutic risk and safety, and practicality are also discussed. Keywords: efficiency, functional analysis, problem behavior, safety, within-session second-by-second analysis.
247

The Influence of Discrete Emotional States on Preferential Choice

Cataldo, Andrea M 13 July 2016 (has links)
Past research has shown that emotion affects preferential choice outcomes. The goal of the present study was to further research on emotion and preferential choice by using mathematical modeling to investigate the effects of specific dimensions of emotion on the underlying mechanisms of preferential choice. Specifically, we aimed to determine whether the concurrent effects of positive-negative valence and situational certainty on attention and information accumulation threshold, respectively, would influence the magnitude of the similarity effect, a robust phenomenon in preferential choice. Participants first underwent either an Anger (negative and certain), Fear (negative and uncertain), or no (Control) emotion manipulation. All participants then completed an apartment choice task that was designed to elicit the similarity effect. A novel framing manipulation was used to test the effects of emotional valence on attention. Both feature framing and emotion condition significantly affected choice outcomes. These results suggest differences in deliberation style between Anger and Fear participants, as well as a surprising impact of alternatives outside the choice set on choice outcomes. Future directions are discussed.
248

Personality and Mood for Non-player Characters: A Method for Behavior Simulation in a Maze Environment

Paige, Noah L 01 December 2020 (has links) (PDF)
When it comes to video games, immersion is key. All types of games aim to keep the player immersed in some form or another. A common aspect of the immersive world in most role-playing games -- but not exclusive to the genre -- is the non-playable character (NPC). At their best, NPCs play an integral role to the sense of immersion the player feels by behaving in a way that feels believable and fits within the world of the game. However, due to lack of innovation in this area of video games, at their worst NPCs can jar the player out of the immersive state of flow with unnatural behavior. In an effort towards making non-playable characters (NPCs) in games smarter, more believable, and more immersive, a method based in psychological theory for controlling the behavior of NPCs was developed. Based on a behavior model similar to most modern games, our behavior model for NPCs traverses a behavior tree. A novel method was introduced using the five-factor model of personality (also known as the big-five personality traits) and the circumplex model of affect (a model of emotion) to inform the traversal of the behavior tree of NPCs. This behavior model has two main beneficial outcomes. The first is emergent gameplay, resulting in unplanned, unpredictable experiences in games which feel closer to natural behavior, leading to an increase in immersion. This can be used for complex storytelling as well by offering information about an NPC's personality to be used in the narrative of games. Secondly, the model is able to provide the emotional status of an NPC in real time. This capability allows developers to programmatically display facial and body expression, eschewing the current time-consuming approach of artist-choreographed animation. Finally, a maze simulation environment was constructed to test the results of our behavior model and procedural animation. The data collected from 100 iterations in our maze simulation environment about our behavior model found that a correlation can be observed between traits and actions, showing that emergent gameplay can be achieved by varying personality traits. Additionally, by incorporating a novel method for procedural animation based on real-time emotion data, a more realistic representation of human behavior is achieved.
249

Structural response of concrete-filled elliptical steel hollow sections under eccentric compression

Sheehan, Therese, Dai, Xianghe, Chan, T.M., Lam, Dennis January 2012 (has links)
The purpose of this research is to examine the behaviour of elliptical concrete-filled steel tubular stub columns under a combination of axial force and bending moment. Most of the research carried out to date involving concrete-filled steel sections has focussed on circular and rectangular tubes, with each shape exhibiting distinct behaviour. The degree of concrete confinement provided by the hollow section wall has been studied under pure compression but remains ambiguous for combined compressive and bending loads, with no current design provision for this loading combination. To explore the structural behaviour, laboratory tests were carried out using eight stub columns of two different tube wall thicknesses and applying axial compression under various eccentricities. Moment-rotation relationships were produced for each specimen to establish the influence of cross-section dimension and axis of bending on overall response. Full 3D finite element models were developed, comparing the effect of different material constitutive models, until good agreement was found. Finally, analytical interaction curves were generated assuming plastic behaviour and compared with the experimental and finite element results. Ground work provided from these tests paves the way for the development of future design guidelines on the member level.
250

[pt] DESENVOLVIMENTO DE UM SISTEMA DE PISO MISTO COM VIGA EM PERFIL ALVEOLAR ASSIMÉTRICO / [en] DEVELOPMENT OF A COMPOSITE FLOOR SYSTEM WITH ASYMMETRIC CASTELLATED STEEL BEAM

CESAR AUGUSTO DE OLIVEIRA FERRANTE 05 May 2020 (has links)
[pt] Sistemas de piso misto, quando comparados a lajes de concreto armado, são uma solução estrutural mais eficiente e econômica. O comportamento geral desses elementos mistos depende da conexão de cisalhamento entre o aço e a laje de concreto. O sistema de piso misto pré-moldado com aberturas de alma apresenta uma solução eficiente e útil que ajuda a reduzir a altura do piso. Este trabalho relata os resultados de ensaios em escala real de vigas mistas e os ensaios de cisalhamento direto da ligação aço-concreto. Além dos ensaios experimentais, uma análise nãolinear em Elementos Finitos foi conduzida com o objetivo de recalcular os resultados dos ensaios com precisão suficiente usando um conjunto de parâmetros consistente. O sistema de piso misto é composto por uma viga de aço assimétrica parcialmente embutida no concreto, e o mecanismo de transferência de cisalhamento foi estabelecido através de uma inovadora conexão de cisalhamento por aderência, atrito e efeito pino (por armaduras transversais passando através de furos na alma). Os resultados dos ensaios indicaram uma ligação rígida produzida pela aderência e atrito da mesa do perfil embutida no concreto, bem como a possibilidade da viga mista de desenvolver sua capacidade resistente ao momento fletor. O modelo analítico proposto fornece uma maneira eficiente de analisar e projetar vigas mistas com mesa de compressão embutida no concreto da laje. / [en] Composite floor systems, when compared to reinforced concrete slabs, are a more cost-effective structural solution. The overall behaviour of these composite members depends on the shear connection between steel and the concrete encasement. The pre-cast composite flooring system with hollowcore section presents an efficient and useful solution that helps to reduc the flooring height. This thesis reports the results of full-scale tests in composite beams and the associated composite connection push-out tests. In addition to the tests, a nonlinear Finite Element analysis was conducted to recalculate the experimental results with sufficient precision using a consistent set of parameters. The system was composed of a partially encased asymmetric steel beam, and the shear transfer mechanism was established through an innovative shear connection by chemical bonding, friction, and dowel action (by transversal reinforcing bars passing through the web s holes). The tests results indicated that a rigid connection was produced by the chemical bonding and friction of the embedded flange profile in the concrete slab, as well as the composite beam s ability to develop its plastic bending moment capacity. The proposed analytical model provides an efficient way for analysing and designing a composite beam with encased compression flanges.

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