The role of common metaphors in Acceptance and Commitment Therapy was examined in a 35 min brief online workshop targeted at body image dissatisfaction. Participants consisted of 24 graduate level students who were randomly assigned to either the, "ACT as Usual" or "ACT without Metaphors" treatment condition. The "ACT as Usual" treatment condition incorporated common ACT metaphors into the workshop while the "ACT without Metaphors" utilized alternative exercises and literal explanations. Both of the workshops covered all six core components of ACT and provided the same basic information. Results of the present study indicated that there was a significant difference between pretest and posttest scores for the AAQ-W for both groups and no significant differences between pre and post CFQ-13 and PASTAS scores. Further, results indicate the use of common ACT metaphors did not significantly influence participant's scores. Future research should examine the use of ACT metaphors in a variety of settings and situations in order to determine their utility.

The present study examined the effects of a brief video-led mindfulness exercise on momentary choice impulsivity as measured by a monetary delay discounting survey. Participants in the experimental group watched a video requiring them to engage in a brief breathing exercise while participants in the control group viewed a video unrelated to the topics at hand. Switch point analyses suggested that the experimental group discounted less steeply following the intervention while the discounting slope of the control group remained relatively unchanged. A t-test comparing the average change in AUC values from pre-test to post-test for both groups revealed a significant difference: t (13.17) = 2.94, p = 0.0114. The experimental group demonstrated greater changes in AUC scores from pretest to posttest (M= 0.1036 ± 0.0328) than the control group (-0.00031 ± 0.01317). Additionally, an F-test was conducted to compare variances between the individual score changes of the experimental group and the control group (p < .05). The results suggest that there was a significant difference between the two groups: F = 5.682, p = 0.0082. The results of this study could have several implications for future research regarding delay discounting and mindfulness as an intervention for impulsivity and suggest that telecommunication may be a viable modality.

The following study aims to understand the effects Acceptance and Commitment Therapy, or ACT, has on individuals who have experienced discomfort through exposure to aversive stimuli. Experiencing discomfort is a natural part of human life. Each person has their own class of responses to respond to discomfort. A typical response may include avoiding an object, person, or situation that had made the person uncomfortable in the past. Batten, Follette, and Aban (2001) found that women who experienced childhood sexual abuse and scored high in experiential avoidance where more likely to engage in high risk sexual behaviors. Avoiding discomfort can have serious repercussions. ACT has been a proven therapy to treat anxiety, gambling, PTSD, eating disorders among other disorders. Previous studies show the effectiveness of ACT on treating discomfort (Cohrane, Barnes-Holmes, & Barnes-Holmes, 2008; Hayes, Bissett, Korn, Zettle, Rosenfarb, Cooper, & Grundt, 1999; Luciano, et al., 2010). This study extends the findings and further supports the utility of ACT to treat discomfort through a laboratory study. This study exposes participants to “disgusting” stimuli to evoke disgust and discomfort. A brief ACT session is administered to half the participants which is compared to a control task which includes a distraction/avoidance task. Findings from this study suggest the utility of ACT to increase tolerance to discomfort.

Muscle disorders are chronic, progressive conditions, the majority of which are without disease modifying treatments. Quality of life (QoL) is reduced in these conditions, and alternative methods, such as psychological intervention, may offer ways to improve QoL. Previous work has suggested that aberrant illness perceptions may be influential targets for psychological interventions; however, emerging evidence suggests that psychological flexibility might offer another treatment target. This thesis first presents a longitudinal investigation of the role of these two variables, alongside disability level, in explaining life satisfaction and mood measured four months later. Participants were recruited from charities and online communities, with data collected via online questionnaires. Here, illness perceptions and psychological flexibility, but not disability level, were cross-sectionally associated with all dependent variables. In prospective analyses psychological flexibility accounted for greater variance in life satisfaction and anxiety; while illness perceptions explained more variance in depression. However, after controlling for variance in time one dependent variables, psychological flexibility alone was predictive of life satisfaction and anxiety at time two. Therefore, psychological flexibility represents a possible influential target for psychological intervention in muscle disorders. Acceptance and Commitment Therapy (ACT) is a psychological intervention specifically designed to improve psychological flexibility. Subsequently, the results of the empirical study imply that ACT is worthy of trial with muscle disorders. However, there has been no comprehensive review of the use of ACT in chronic disease or long-term conditions. Therefore, Chapter 2 presents a systematic review of ACT as applied to chronic disease/long-term conditions. The aims were to collate all ACT interventions with chronic disease/long-term conditions; evaluate their quality and comment on efficacy. Ovid MEDLINE, EMBASE and Psych Info were searched, with a further search of citing articles undertaken using Google Scholar. Studies with mental health or chronic pain populations were excluded. Study quality was then rated, with a proportion re-rated by a second researcher. Seventeen studies were included, of which: eight were randomised controlled trials (RCTs), three used pre-post designs, and seven were case studies. A broad range of applications were observed (e.g. improving quality of life and symptom control, reducing distress) across many diseases/conditions (e.g. HIV, cancer, epilepsy). However, study quality was generally low, and many interventions were of low intensity. The small number of RCTs per application and lower study quality emphasise that ACT is not yet a well-established intervention for chronic disease/long-term conditions. However, there was promising evidence for certain applications: the parenting of children with long-term conditions, seizure-control in epilepsy, psychological flexibility and possibly self-management/lifestyle. The studies comprising this thesis suggest that, whilst psychological flexibility appears influential in muscle disorders, high-quality research into ACT interventions for chronic disease/long-term conditions is generally lacking. Therefore one cannot confidently generalise from existing studies that ACT will improve outcomes in muscle disorders. Thus an evaluation of ACT in the context of muscle disorders is now required. This should adhere to the methodological suggestions provided in the systematic review.

M.Comm.

An estimated 18.6% of adult Americans struggle with mental health symptoms, 22% of whom experience significant functional impairment qualifying them for status as having a serious mental illness (SMI). Despite high prevalence rates, many with mental health symptoms do not receive treatment. Barriers to treatment include those at both individual (i.e. lack of insurance) and environmental (i.e. lack of access) levels. Mental health symptoms causing an individual to be at risk for harm to self or others may lead to legal involvement via involuntary civil commitment (ICC) and evaluation. Although ICC statutes have been adopted throughout the United States, relatively little is known about ICC-involved populations and ICC caseflow. This study extends the literature by providing a description of the ICC population in southern Arizona. Findings identify risk and protective case variables in predicting ICC caseflow. Furthermore, this study is the first to examine two potential sources of problems within the ICC process: 1) disproportionate ICC-contact compared to population-based expectancies and 2) rate of agreement between ICC evaluating physicians regarding an individual’s mental health diagnoses.

In recent years the deregulation of energy markets and expansion of volatile renewable energy supplies has triggered an increased interest in stochastic optimization models for thermal and hydro-thermal scheduling. Several studies have modelled this as stochastic linear or mixed-integer optimization problems. Although a variety of efficient solution techniques have been developed for these models, little is published about the added value of stochastic models over deterministic ones. In the context of day-ahead and intraday unit commitment under wind uncertainty, we compare two-stage and multi-stage stochastic models to deterministic ones and quantify their added value. We show that stochastic optimization models achieve minimal operational cost without having to tune reserve margins in advance, and that their superiority over deterministic models grows with the amount of uncertainty in the relevant wind forecasts. We present a modification of the WILMAR scenario generation technique designed to match the properties of the errors in our wind forcasts, and show that this is needed to make the stochastic approach worthwhile. Our evaluation is done in a rolling horizon fashion over the course of two years, using a 2020 central scheduling model of the British National Grid with transmission constraints and a detailed model of pump storage operation and system-wide reserve and response provision. Solving stochastic problems directly is computationally intractable for large instances, and alternative approaches are required. In this study we use a Dantzig-Wolfe reformulation to decompose the problem by scenarios. We derive and implement a column generation method with dual stabilisation and novel primal and dual initialisation techniques. A fast, novel schedule combination heuristic is used to construct an optimal primal solution, and numerical results show that knowing this solution from the start also improves the convergence of the lower bound in the column generation method significantly. We test this method on instances of our British model and illustrate that convergence to within 0.1% of optimality can be achieved quickly.

The Sport Commitment model (SCM) is a well-known theoretical framework to illustrate how the psychological state of commitment to sport has been influenced and studied in able-bodied persons. Considering the characteristics and lived experiences of people with disabilities, additional antecedents of sport commitment were added in the structure of the SCM. In order to extend the application of this revised SCM to persons with disabilities, the concept of three levels (personal, social, and environmental) of Bronfenbrenner’s ecological model was employed to differentiate the impacts of nine antecedents to sport commitment. The primary purpose of this study was to examine the revised SCM in terms of the magnitude of contribution of nine antecedents (enjoyment, personal investment, involvement opportunities, social constraints, involvement alternatives, self-efficacy, negative consequence of sport participation, social support, and accessibility of sport facilities and settings) on sport commitment to athletes with disabilities. The second purpose of this study was to investigate the superiority between original and alternative sport commitment models (mediation and direct/indirect model). A total of 157 adult athletes (Mean age= 34.87, SD = 11.78) with physical disabilities from team and individual sports across the United States, Europe, and Asia completed an online survey of 60 items across the nine antecedents hypothesized to influence sport commitment in athlete with disabilities. Results indicated involvement opportunities, followed by personal investment, were the strongest predictors of sport commitment (R2 = 65). In contrast, enjoyment, social constraints, involvement alternatives, self-efficacy, negative consequence of sport participation, social support, and accessibility of sport facilities and settings had no significant prediction on sport commitment. Chi-square difference test showed the direct/indirect model (χ2 (211) = 318.41; RMSEA = .05; CFI = .97; SRMR = .06) had better goodness-of-fit indices than the mediation model (χ2 (215) = 390.55; RMSEA = .06; CFI = .95; SRMR = .11). Based on the principle of parsimony, the original model (χ2 (215) = 384.95; RMSEA = .07; CFI = .95; SRMR = .06) was deemed a better model to understand the mechanism of sport commitment than the direct/indirect model. The SCM was an effective theoretical framework for adult athletes with disabilities. However, it still requires more studies to understand its effectiveness to other developmental ages and stages of athletes with disabilities.

Magister Commercii - MCom / Consent for the research study was obtained from the divisional executive of the financial services division being researched and all ethical factors were clarified. All potential participants were engaged in a divisional communication session where participation was advised to be voluntary and anonymity and confidentiality was assured. The results of the study revealed that there was no statically significant relationship between intention to quit and organisational commitment but a statically significant relationship between organisational commitment and age, tenure, marital status and staff with dependants respectively were revealed. Further to that, a statistically significant relationship between intention to quit and age, tenure, marital status was also revealed. Therefore, based on the understanding gained, and the relationship it had with respect to the biographical factors used in the study, it presents organisations with the insight and opportunity to better retain staff. Clear understandings of the limitations of the findings presented are also discussed and additional recommendations for future research are also provided. / South Africa

Magister Commercii (Industrial Psychology) - MCom(IPS) / Set against the tenuous relationship between government (public sector), organisations (private sector) and trade unions, employees’ commitment to the success of their respective organisations are of utmost importance. Heugens and Schenk (2004) maintains stakeholders may oppose restructuring efforts as invariably some constituencies will be likely to lose a strategic advantage as a result of drastic change such as a restructure. This reality has resulted in these stakeholders having to find a common ground to ensure economic competitiveness and longevity of South African organisations. Where this common ground has been elusive, organisations need to find the balance between profitability, environment and its people. According to the King III Report (2009, as cited in Du Plooy & Roodt, 2013) this is referred to as the triple bottom line that is profit, planet and people, which are integrally linked to employee turnover and organisational strategy. Organisational commitment is a key factor to success for organisations in order to obtain and maintain a competitive advantage. Coetzee and Botha (2012) posit that organisations in today’s competitive world require each employee to be committed to the organisation’s objectives and function as an effective team. A competitive advantage is needed to achieve high performance (Nienaber & Masibigiri, 2012). The working world has evolved from one where job security is no longer as prevalent as it used to be. Consequently and understandably, employees’ commitment to their organisations has diminished. Organisations are required to now investigate, understand and put measures in place to grow employee commitment in order have a successful business operation. This study intended to primarily establish whether a relationship exists between organisational commitment and turnover intentions amongst employees in an organisation undergoing restructuring. Additional variables namely age and tenure were used to establish if these variables have any bearing on levels of organisational commitment. The matter of organisational restructuring may act as an antecedent variable to both organisational commitment as well as turnover intentions. An organisational restructuring is likely to have a negative effect on employees’ organisational commitment. Thus, the affective commitment, continuance commitment and normative commitment of employees were also contrasted with turnover intentions. Correspondingly, news of an impending restructure may serve to increase employees’ intentions to terminate employment with the organisation. The sample included 144 respondents (n = 144) from an organisation within the hospitality industry. A method of non-probability, convenience sampling was utilised due to the nature of the study. A Biographical Questionnaire, Organisational Commitment Questionnaire and Turnover Intention Questionnaire were utilised for data collection purposes. The biographical questionnaire aimed to elicit among others important details such as gender, race, age, marital status, qualifications, language preferences and years of service were used for statistical purposes. Once the information was collected, the Pearson data analysis technique and Analysis of Variance technique were used to establish the relationships and differences between the respective variables under investigation. The results in the study indicate that significant inverse relationships exist between organisational commitment and turnover intentions. Significant differences were found in organisational commitment based on age and tenure. Similar statistically significant differences were discovered in turnover intentions according to employees’ age and tenure. Affective, continuance and normative commitment exhibited significant relationships with turnover intentions. The study in closing makes reference to the limitations experienced in the study as well as recommendations for future research especially on organisational commitment and turnover intentions of employees within a restructured or restructuring environment.