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The standard ΛCDM model of cosmology has been very successful in matching a large set of observational constraints and describes accurately the evolution of our Universe. Within this framework, the gravitational collapse of cold dark matter structures depends solely on the cosmological background. The formation of galaxies inside these haloes is thought to be determined by complex baryonic process and we rely on numerical techniques to model their effects. Here, we investigate the impact of the cosmological background on galaxy formation. We take the advantage of state of the art cosmological hydrodynamical simulations from the eagle suite to vary the cosmological parameters, in particular, the cosmological constant, to test its effect on the efficiency of star formation. We use this set of new simulations to calculate the likelihood of the observed value of the cosmological constant, given a measure of the multiverse. We discuss the implication of our results in the context of the anthropic principle. We use this framework to develop a fully analytic model of galaxy formation that connects the growth of dark matter haloes in a cosmological background, with the build-up of stellar mass within these haloes. The model identifies the physical processes that drive the Galaxy-Halo co-evolution through cosmic time. Despite the complexity of the baryonic processes involved, galaxy formation is revealed as a remarkably simple process, where the instantaneous star formation efficiency within halos is only a function of their virial temperature and can be described with a ‘single’ differential equation. We find that the model reproduces self-consistently the shape and evolution of the cosmic star formation rate density, the specific star formation rate of galaxies, and the galaxy stellar mass function, both at the present time and at high redshift. Finally, we use the merger rate of supermassive black holes in the eagle simulations to estimate the expected event rate of gravitational wave signals that could be resolved by future space-based gravitational wave detectors. We discuss the power of these detections to provide information about the origin of supermassive black holes and the initial mass distribution of black hole seeds.

Higher education organizations, like the rest of the United States workforce, faces an ever-changing world to which they must adapt. Organizations are recognizing that their workforce ideologies are also changing because their employees consist of multiple generations working together. These multiple generations do not necessarily always agree on processes and outcomes; however, the continuity of the organization is dependent on them working and communicating together. There are leaders in organizations who successfully lead multiple generations with strong positive outcomes. Some of these leaders may also be mentors who mentor across the generations successfully. Hidden in the leaders' mentoring styles are unrecognized pedagogies used to successfully prepare the multiple generation workforce. This study identified the personal pedagogies and leadership styles of mentors in higher education institutions and how they help their mentees and workplace teams move forward. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The problem with the first-level digital divide in U.S. schools has been well-documented for over thirty years. However, it is not only important to acknowledge that a divide exists, but it is important to understand why it matters, how it affects students and their futures, and what influences contribute to bridging the divide. This study used Clark and Estes' (2008) conceptual framework to identify the knowledge, motivation, and organization gaps related to parents supporting their children on computers at home. Through a study that included a general literature review and the administration of surveys and interviews, influences on parents were analyzed. Parents who participated in this study demonstrated self-efficacy in using computers and saw value in using computers to support students' academic goals. Parents also knew about safety issues related to student online access, and how to access computer literacy support. Recommendations for the organization were provided in this study related to ways in which validated influences could be closed through parent training and feedback. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

This thesis focuses on Chicana photographer Laura Aguilar and the role disability had on her artistic practice. My analysis of Aguilar’s work focuses on several images from Aguilar’s Nature Self-Portrait (1996-2007) and Grounded (1996-2007) series, and three photographs titled Three Eagles Flying (1993), Access + Opportunity= Success (1993), and Will Work For #4 (1993). I approach these images through a disability studies framework of the body-mind to emphasize the influence of Aguilar’s non-normative identity on her photography. Throughout my analysis, I find that her devalued position as a disabled, poor, queer Chicana is a source of knowledge for her visualizations of exclusion and discrimination of minorities. I expand on conversations surrounding her nude self-portraits in nature by discussing the ontological relationship between Aguilar and the American Southwest deserts and the care work she established. My thesis is based on disability and is structured by the diverse manifestations of Aguilar’s exploration of her non-normative body-mind

Hunter recruitment and retention could be improved by securing public hunting access to private properties, especially for members of the public without means to purchase hunting lands of their own. However, private landowner participation in such “walk-in access” (WIA) rely on the willingness of landowners to relinquish partial control over lands that are often invested with emotional or utilitarian significance. To persuade landowners to open their lands and resources to the public, it is first necessary to gain a deeper understanding of what internal factors will most effectively impact their intent to do so. We conducted a self-administered mail-back questionnaire of private landowners in Minnesota with properties eligible for or enrolled in the state’s WIA program, and data were analyzed through linear modeling using multi-item variables constructed from individual survey items. We based our variables upon factors demonstrated through previous research to be integral to landowners' conservation decision-making, and used hierarchical regression to measure the influence of place attachment and trust variables on landowner attitudes. Landowners' land ethic and willingness to trust exerted significant positive influence on their attitudes toward WIA, while place dependence negatively impacted landowner attitudes. Future studies may consider further measurement and analysis of subjects’ land ethic and willingness to trust in order to corroborate whether these factors can serve as powerful and reliable predictors of attitudes.

Out-of-hospital cardiac arrest (OHCA) results in nearly 350,000 deaths in the United States annually. Survival after OHCA is dismal, with regional estimates suggesting an overall case fatality rate of between 92% and 96%. High mortality following OHCA persists despite advances in resuscitation methodology that result in the successful resuscitation of a substantial fraction of patients (~40%). It is known that some patients experience another OHCA after resuscitation. This secondary OHCA, called rearrest, has not been extensively characterized, but it is known that rearrest correlates with poor OHCA survival prognosis after OHCA. Further understanding of rearrest may enable its prevention and development of optimal treatment strategies, potentially increasing survival after OHCA. Utilizing data from the OHCA surveillance program of the Resuscitation Outcomes Consortium, this dissertation addresses the need for further characterization of rearrest, focusing on patient, treatment, and electrocardiographic characteristics. The results of this study indicate several characteristics that distinguish cases with and without rearrest. Of these, median income and electrocardiographic characteristics derived from the QT-interval were the most robustly associated with rearrest case status. Time-to-rearrest was correlated with rearrest event number, presenting OHCA electrocardiogram rhythm, and when measured over the first 5-minutes following resuscitation in patients with rearrest, standard deviation of heart rate. While the characterization of rearrest cases was comprehensively reported with the available data in this study, limited inference could be drawn regarding the prediction and prevention of rearrest due to a lack of patient history data and a large amount of missing electrocardiographic data. Still, this study lays down a clear path to future research, indicating promising directions for further filling in the knowledge gaps necessary to increase survival after OHCA. The public health significance of this work is rooted in the identification and characterization of an important determinant of a major source of mortality in the developed world, OHCA. The findings of this study provide a novel basis for further investigations aiming to save some of the hundreds of thousands of lives that are claimed by OHCA each year, potentially through public health interventions executed through emergency medical services.

We want to find out how applicable the practices described in American books and articles are to Mexico; what limitations there are for applying the board generalizations contained in the United States literature to the Mexican practice; how much of the printed material that Mexican businessmen have been reading, has become real practices in Mexico; and possibly to what extent Mexican books in this field should be different from American.