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The human heart cannot regenerate following myocardial infarction and instead forms a fibrotic scar that impairs cardiac function and can lead to heart failure. Cardiac regeneration aims to treat the injured heart by stimulating the heart to repair itself. The Astyanax mexicanus is a uniquely suited model of cardiac regeneration as it comprises two closely related populations: (1) the 'regenerative' surface (SF) population and (2) the 'non-regenerative' Pachόn (PF) cave population. The immune response to injury is known to be a key regulator of successful regeneration. However, how this response differs between SF and PF populations is unknown. To fully characterise the A. mexicanus immune response, single cell RNA-sequencing, differential gene expression analysis, histological staining and in situ hybridisation were used to determine the immune cell populations present in the heart at 1-, 3-, 7-, 14- and 30 days post-cryoinjury (dpci). Pharmacological perturbations of the A. mexicanus immune response were then used to explore whether identified differences in the regenerative and scarring immune responses to cardiac injury were exerting control on regenerative capacity. Striking spatiotemporal differences were found in the dynamics of both myeloid and lymphoid populations in the PF and SF. Immediately after injury, the non-regenerative PF showed a stronger response to injury with a significantly greater influx of neutrophils into the wound (1dpci p=0.0156; 3dpci p=0.0075). By 7dpci, this inflammatory response was resolved, and differential gene expression analysis showed that PF neutrophils had returned to the uninjured state. In contrast, the regenerative SF showed a greater immune response at the late stages of cardiac healing (7-, 14- and 30dpci). Specifically, at 7- and 14dpci, a transcriptionally unique population of neutrophils was observed in the SF that remained activated and upregulated TNFα-NFκB signalling. Furthermore, a stark contrast in the B cell response was observed: SF displayed a significant influx of B cells at 14- and 30dpci that was absent in the PF (p<0.005). Inhibition of the SF immune response using 7-14dpci Dexamethasone treatment did not impair the regenerative capacity of the SF but did significantly disrupt scar organisation, resulting in scars that closely resembled time-matched PF scars. This research represents a significant leap forward in our understanding of how the immune response differs between successful regeneration (SF) and scarring (PF). However, further studies will be required to determine the role of late-stage SF neutrophils and B cells in successful regeneration before novel therapeutic targets can be identified for immunomodulation in heart attack patients.

The role of social capital in forming organizational commitment is the focus of this research. Organizational social capital is the idea that social relationships have value in the organization. The theoretical framework is based on Kanter's (1993) structure of organizational commitment. This research views the structure within organizations based on global empowerment, job satisfaction, organizational commitment, and social capital. In addition, the role that race, income, and education affect the organizational structure is also taken into account. The organizational configuration was assembled using a structural equation model with latent variables employing a sample of 235 certified nurse aides. The sample was collected from 10 nursing homes in the Dallas-Ft.Worth metropolitan area. It was expected that Kanter's general format is reestablished within the sample. In fact, the study found that empowerment significantly influences job satisfaction. In turn, job satisfaction does foster organizational commitment. Although Kanter's original thesis was supported in this analysis, it was also determined that social capital plays a significant mediating role in creating organizational commitment. Furthermore, this research indicates that social capital alone can create organizational commitment. Thus, in conclusion, this research builds on Kanter's original idea and argues that organizational commitment is based on job satisfaction, global empowerment, and social capital.

Charlotte Perkins Gilman (1860-1935), writer and lecturer, provided philosophical guidance to the feminist movement of the late nineteenth and early twentieth centuries, During a career spanning the years 1890 to 1935 she published eleven books, wrote articles for popular magazines, and lectured throughout the United States and Europe. Between 1909 and 1916 she wrote, edited, and published a monthly magazine entitled The Forerunner. Gilman's efforts dealt primarily with the status of women, but she described herself as a humanist rather than a feminist. She explained that her interest in women arose from a concern that, as one-half of humanity, their restricted role in society retarded human progress. Thus, Gilman's contribution to feminism must be viewed within the context of her humanist philosophy. Gilman's contribution to feminism lies in her diagnosis of woman's predicament as ideological rather than political and, hence, subject to self-resolution. The uniqueness of Gilman's approach is in the autonomous nature of her solution: Woman, through the full use of her human powers, could achieve the equality that decades of political agitation had failed to accomplish. The rationale for this dissertation lies in the premise that Gilman's humanist approach to feminism made a significant contribution in her own day and offers insight into women's present status.