Interactions of large amplitude solitary waves in viscous fluid conduits

The free interface separating an exterior, viscous fluid from an intrusive conduit of buoyant, less viscous fluid is known to support strongly nonlinear solitary waves due to a balance between viscosity-induced dispersion and buoyancy-induced nonlinearity. The overtaking, pairwise interaction of weakly nonlinear solitary waves has been classified theoretically for the Korteweg-de Vries equation and experimentally in the context of shallow water waves, but a theoretical and experimental classification of strongly nonlinear solitary wave interactions is lacking. The interactions of large amplitude solitary waves in viscous fluid conduits, a model physical system for the study of one-dimensional, truly dissipationless, dispersive nonlinear waves, are classified. Using a combined numerical and experimental approach, three classes of nonlinear interaction behavior are identified: purely bimodal, purely unimodal, and a mixed type. The magnitude of the dispersive radiation due to solitary wave interactions is quantified numerically and observed to be beyond the sensitivity of our experiments, suggesting that conduit solitary waves behave as "physical solitons." Experimental data are shown to be in excellent agreement with numerical simulations of the reduced model. Experimental movies are available with the online version of the paper.Comment: 13 pages, 4 figure

Building Renewed Relevance: Portraits of CEOs Rebranding Iconic Nonprofit Organizations

In the United States, we often refer to the social sector as one leg of a three-legged stool. The private and public sectors support the other two legs. The social sector made up of nonprofit, nongovernmental, and charity organizations, contributes to the development of American society by focusing on social good rather than the desire to make profit. For decades, the sector has functioned as the social conscience of our society. However, many iconic, legacy nonprofits have struggled to keep their relevance in today’s world: their creation tied to a past societal problem, their mission and brand no longer germane to today’s generations. This study examined top-level—Chief Executive Officer (CEO)—leaders of iconic, legacy nonprofit organizations who have worked to implement reform and change through rebranding for renewed relevance. The research looked particularly at these primary areas: (1) What drove the leader to innovate and rebrand their organization and what does it mean to them personally and professionally? (2) What leadership practices did the CEO incorporate to allow the changes and reforms to be successful and why does the CEO believe they worked? The research methodology utilized for this dissertation was qualitative portraiture; portraiture interviews were audio and video recorded for research purposes. This research adds to the body of knowledge about successful leaders of iconic nonprofit organizations and the best practices for achieving renewed relevance through nonprofit rebranding. This research could aid with building an awareness of the successes and challenges of nonprofit leaders and could increase the interest of potential organizational stakeholders in the future. Six supplemental Mp4 video files of participant interviews accompany this dissertation. This dissertation is available in open access at AURA: Antioch University Repository and Archive, http://aura.antioch.edu/ and OhioLINK ETD Center, https://etd.ohiolink.edu/

A Bioarchaeological Approach to Social Transition in the Pre-Hispanic Andes: A Diachronic Study of Health at Tumilaca la Chimba, Peru

This thesis investigates the relationship between long-term, macro-scale social change and systemic stress by analyzing osteological data from two occupations at the archaeological site of Tumilaca la Chimba, Peru. The first dates to the terminal Middle Horizon (ca AD 950-1250) and was established as the Tiwanaku state underwent collapse. Despite political fragmentation, this occupation is characterized by substantial cultural continuity in Tiwanaku practices. The second occupation dates to the Late Intermediate Period (LIP) (ca AD 1250-1476) and is associated with significant changes in cultural practice, suggesting a process of population replacement. This study compares skeletal data derived from cemeteries associated with each occupation. Paleopathological analysis of 20 individuals from the terminal Middle Horizon cemeteries and 23 individuals from the LIP cemetery reveals significant differences in age and sex and in skeletal pathologies. These results are a valuable addition to current literature examining the impact major political reorganization has on individuals

Inspiration for the Future: The Role of Inspiratory Muscle Training in Cystic Fibrosis.

Cystic fibrosis (CF) is an inherited, multi-system, life-limiting disease characterized by a progressive decline in lung function, which accounts for the majority of CF-related morbidity and mortality. Inspiratory muscle training (IMT) has been proposed as a rehabilitative strategy to treat respiratory impairments associated with CF. However, despite evidence of therapeutic benefits in healthy and other clinical populations, the routine application of IMT in CF can neither be supported nor refuted due to the paucity of methodologically rigorous research. Specifically, the interpretation of available studies regarding the efficacy of IMT in CF is hampered by methodological threats to internal and external validity. As such, it is important to highlight the inherent risk of bias that differences in patient characteristics, IMT protocols, and outcome measurements present when synthesizing this literature prior to making final clinical judgments. Future studies are required to identify the characteristics of individuals who may respond to IMT and determine whether the controlled application of IMT can elicit meaningful improvements in physiological and patient-centered clinical outcomes. Given the equivocal evidence regarding its efficacy, IMT should be utilized on a case-by-case basis with sound clinical reasoning, rather than simply dismissed, until a rigorous evidence-based consensus has been reached

Developing real-time PCR assay for detection of multi-drug Salmonella strains in pigs

The main objective of this study was to develop a rapid, sensitive and accurate real-time detection assay for multi-drug resistant (MDR) Salmonella strains isolated from pigs. Initially, standardized procedures for use with real-time PCR using SYBR green were developed to evaluate selected primers, detection limitations using two predominant strains: S. typhimurium phage types DT104 and DT193

The role of truck wash practices in dissemination of Salmonella and Campylobacter in commercial swine production

This study investigated the sources of two foodborne pathogens, Salmonella and Campylobacter in a commercial swine production system. Pathogens were characterized using conventional culture and isolation techniques and antibiograms