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EXPERIMENTAL CHARACTERIZATION OF POWER GENERATION OF A SMALL WIND TURBINE WITH VARIABLE DUCTED GEOMETRY
Full text linkWind turbines provide renewable energy but must be installed at suitable locations to maximize power generation. Applying duct geometry to wind turbines can increase output power, allowing for the integration into urban applications where space is limited, and visual pollution must be minimized. Therefore, the objective was to determine the change in output power for a wind turbine with variable area ducting comprised of a converging inlet nozzle and a diverging outlet diffuser. Parametric studies of 3D-printed models were conducted in a low-speed wind tunnel at 5 m/s to determine the optimal duct angle and area ratio with the greatest power output. Power was measured from an electrical load applied with a potentiometer to a turbine with a 47 mm blade diameter. For the small-scale model and low-speed test conditions, the addition of variable geometry improved the output power when compared to a constant area duct surrounding the turbine. The best performing nozzle with an area ratio of two and a double contraction angle of 90°had a power increase of 53.7%. The best performing diffuser with an area ratio of two and a double expansion angle of 10° had a power increase of 93.0%. However, when comparing the variable area duct geometry to a bare turbine with any ducting, minimal power improvement and even power reduction was observed. Lastly, combining both an inlet and outlet diffuser, resulted in an 84.4% power increase compared to the turbine with a constant area duct despite a smaller inlet area. This test case also resulted in the highest wind power harnessed per inlet area at 6.80 W/m2 compared to 4.87 W/m2 for the bare turbine
ASSESSING REPETITIVE LOSS FACTORS IN MIAMI-DADE AND BROWARD COUNTIES, FL
Full text linkThis dissertation examines repetitive loss factors in Miami-Dade and Broward Counties, Florida. It focuses on physical building characteristics and socioeconomic characteristics in an historic analysis of claims data from 1977 through 2014. Later, the focus is on predicted areas, or “hotspots” where climate-change induced sea level rise in conjunction with increased storm activity may cause increased flooding in the future. The study employs various statistical models, including Poisson and negative binomial regression modeling, spatial regression modeling and hot spot analysis to analyze FEMA property claims data and socioeconomic indicators.
The first part investigates the relationship between building characteristics and flooding claims, revealing that construction after the development of Flood Insurance Rate Maps (FIRM) in the mid-1970s, elevated building structures and high ground elevations are associated with lower claim frequencies.
The second part explores socioeconomic factors that influence repetitive loss, finding that low socioeconomic status, minority status, and increased living density (multi-unit housingstructures) are predictors of high claims costs. There is a notable shift in the vulnerability patterns between 1990-2003 and 2004-2014, potentially connected to demographic changes in the region.
The third part assesses the potential impacts of sea level rise on repetitive loss properties, by the identification of coastal hot spots and simulation of inundation scenarios based on hurricane events in recent history. Using LiDAR-derived elevation data and hydrologic modeling, the study displays future flooding risks under various sea level rise scenarios for both 2050 and 2100.
This comprehensive analysis aims to provide valuable insights into the complexity of repetitive loss claims history and the contribution of potential environmental factors that may impact claims in the future. These findings may have important implications for flood risk management, urban and regional planning efforts, and climate change adaptation strategies across coastal communities of South Florida, that are particularly vulnerable to sea level rise and the impacts of storm activity across the region
The Current and Potential Applications of CRISPR Technology
Full text linkCRISPR-Cas9 is a genetic engineering technology that allows for precise editing of DNA sequences. It utilizes a guide RNA that targets the endonuclease Cas9 to make a double-strand DNA break at a specific site. This technology has proven useful in both clinical and biomedical settings. This review discusses some prominent applications including treatment of Transthyretin Amyloidosis, cell cloning for pharmaceuticals, refractory cancer, sickle cell disease and β-Thalassemia. Furthermore, two methods that utilize CRISPR-Cas9 to prevent hereditary retinoblastoma are proposed
Exploring Infant Toy Interactions in Free Play Environments
Full text linkInfants’ interactions with toys play a crucial role in their early cognitive and motor development, yet much of the research on this topic has been conducted in controlled laboratory settings, which may not accurately reflect the diversity of toys and interactions infants experience in their natural environments. This study uniquely examined these interactions in a home setting by utilizing an online video conferencing platform. This study investigated how toy properties influence manual infant-object interactions during dyadic tabletop free play, where mothers selected the toys for the session. Within the confines of this study, results show that infants spend significantly more time manipulating traditional organizational/fine motor toys compared to other toy categories (i.e., responsive, art, etc.). This study highlights the importance of considering the natural context in which toy interactions occur and provides insights into how different types of toys impact early behaviors and exploration
Use of a Novel Plant Essential Oil-based Insecticide for Insect Control in Household Gardens and Lawns
Full text linkInsecticide use has increased as population and agricultural demand for crops grows. Commercial insecticides contain active ingredients that are often harmful to humans and the environment. A viable alternative to this concern is developing and using insecticides with low toxicity and minimum risk to the environment. In this study, we sought to empirically assess the effectiveness of an insecticide based entirely on plant essential oil active ingredients, which contain complex secondary metabolites. Our results show that a concoction of several plant essential oils was effective in killing a wide range of household garden insect species and bedbugs, encompassing five orders of Insecta (Coleoptera, Diptera, Hemiptera, Lepidoptera, and Neuroptera) and at least 22 families. This insecticide is also fatal to four tick species (class Arachnida, order Ixodida, family Ixodidae). Due to the likely major economic and environmental benefits of using significantly less toxic, plant-based pesticides on a large scale for agriculture and residential housing, our study highlights the potential of plant essential oil-based insecticides as an effective and environmentally safe means of pest control
#TRIBE: A STUDY ON DIGITAL TRIBALISM IN SAUDI ARABIA
Full text linkThis dissertation examines digital tribalism in Saudi Arabia as a lens through which to explore the complex interplay between state, identity politics, and social media in an era of rapid transformation. Amidst ambitious modernization efforts under Vision 2030 and ongoing economic restructuring, the Saudi state has sought to establish a national identity by leveraging tribal heritage. This study investigates how the three major tribes, Harb, Qahtan, and Otaibah, are responding to rapid modernization through an examination of their digital presence on X (formerly Twitter).
Employing a comparative case study design and content analysis of three years of digital activity, this research probes whether the tribes’ engagement with digital platforms constitutes an act of cultural preservation or a form of resurgence. The analysis reveals that tribal actors use social media not merely as archival tools but for identity strengthening and communal mobilization. Key themes emerging from the data include tribal land issues, historical legitimacy, gender roles, and the evocation of religious and cultural symbols.
The findings suggest that digital tribalism is a dynamic form of political expression, wherein tribes simultaneously adapt to and resist modernization. While public rituals, folklore, and tribal values are reinforced, the absence of certain traditions, such as spiritual practices, underscores the constraints of digital representation. Moreover, tribal discourse reflects a call back to tribalism as a form of resurgence.
By situating tribal digital discourse within the broader context of state formation and resilience, this dissertation contributes to scholarship in comparative politics, digital media studies, and political sociology. It argues that tribal digital engagement represents not a retreat into tradition, but a strategic recalibration of identity and power in a rapidly evolving socio-political landscape
REASSESSING PRE-CERAMIC MORTUARY PRACTICES IN FLORIDA
Full text linkThis thesis synthesizes mortuary practices among Florida’s Paleoindian to Late Archaic populations, from the earliest documented burials to approximately 2,500 BP. While sites like Windover and Little Salt Spring are well-studied, broader burial traditions across the region remain underrepresented. To address this, data from fifteen key sites, chosen for geographic and temporal diversity, were compiled and analyzed. Using an exploratory research design, a descriptive methodological framework was developed to evaluate cemetery types, burial positions, artifact associations, demographic indicators, and spatial orientation. Methodological challenges such as poor preservation, site destruction, and inconsistent documentation are also considered. Findings are contextualized within wider regional and chronological patterns to identify trends in mortuary behavior and guide future inquiry. This work contributes a structured dataset and analytical model for understanding early Floridian burial practices and provides a foundation for comparative studies within the broader Southeastern United States
MICROPLASTICS IN COASTAL SEDIMENTS
Full text linkMarine and coastal sediments are considered to be sinks for plastic pollution. The dispersal of microplastics through ocean dynamics (winds, waves, currents, and tides) may be dependent on the type of microplastic and sedimentation of the coastal environment. Coastal tourism significantly contributes to the sources of plastic, especially in the state of Florida. Microplastic pollution impacts all facets of the environment impacting ecosystem services, wildlife, and human health. However, few studies have been conducted to quantify the abundance and type of microplastics found in coastal sediments under different seasonal conditions. This project aimed to evaluate the abundance of microplastics in beach sediment in south Florida to be compared with wave energy and differing beach accessibility types. There are currently no known studies documenting microplastics in sediments in relation to high-energy versus low-energy wave dynamics in Southeast Florida nor evaluation of microplastic abundance within distinct recreational usage such as public, park, and private beaches. This study quantified microplastic abundance and variation cross-sectionally on the beach, assessed proximal water content for microplastics, and compared with beach use type and local wave energy. Study sites included three regionally similar, but recreationally distinct beaches located in Palm Beach County, Florida. The study sites were sampled multiple times seasonally in 2024 (i.e., summer and winter). Fourier Transform Infrared Spectroscopy (FTIR) was explored as a method to identify and quantify specific polymer type of individual pieces. This study found that microplastic abundance is related to sediment mean grain size, the accessibility of beaches, and microplastic type (by shape) and size varied cross-shore with regards to beach morphology. Given the increasing pollution of microplastics, identifying the microplastic conditions along Southeast Florida beaches, will help inform conservation and management initiatives that can be established to protect these vital coastal environments
VETERANS IN TIMES OF CRISIS: THE IMPACT OF VETERAN STATUS ON UNEMPLOYMENT
Full text linkThe purpose of this research is to investigate the impact of veteran status on unemployment in times of crisis. Driven by the social identity theory, we argue that people’s identity deriving from his or her military background makes them more valuable assets in the work environment, specifically in times of crisis, because of their human capital. We utilize the coronavirus pandemic as the exogenous shock in the labor marketplace, capturing the crisis environment. Due to the veterans’ human capital driven by their leadership and entrepreneurial characteristics from their military experience, we argue that individuals with veteran backgrounds have stronger labor market outcomes from the unemployment perspective than non-veterans in times of crisis. This study contributes to literature on the labor outcomes of protected groups and the effects of the pandemic. The research provides new evidence regarding how veteran status affects unemployment in the crisis environment. JEL Classification: G21; J14; J15; H8
SLEEP QUALITY, VOLUMETRIC BRAIN BIOMARKERS FOR AD, EXECUTIVE FUNCTION, & COGNITIVE DECLINE IN OLDER ADULTS
Full text linkObjective: Our aims were to examine differences in sleep quality sub scores and total scores across diagnostic groups cross-sectionally and longitudinally, correlate executive function scores and volumetric biomarkers of AD (prefrontal cortical and hippocampal volumes) with sleep quality scores, and explore how demographic variables may serve to moderate how sleep quality effects diagnosis. Method: 381 participants were classified into 3 diagnostic groups (Cognitively normal (CN), mild cognitive impairment (MCI), and dementia) based on the CDR global score. Prefrontal cortical volume, hippocampal volume, and PSQI total and sub scores were used as predictors of progression status. Daytime dysfunction, sleep duration, and adjusted PSQI global scores were significantly different across diagnostic groups cross sectionally. Within subject effects of subjective sleep quality from baseline to follow-up were found with varied scores across diagnostic groups. Subjective sleep quality, sleep duration, and sleep disturbance scores significantly predicted progressor status, with poorer subjective sleep quality, longer sleep duration, and increased sleep disturbances indicating greater likelihood of cognitive diagnosis progression. Conclusion: we identified cognitive markers for progression in specific sleep quality components. These findings provide further evidence of the benefit of measuring sleep quality in abnormal aging populations and may indicate PSQI sub scores as potential markers of progression to MCI or dementia. It may be recommended for future research to adapt the traditional PSQI to abnormal aging populations, in which longer sleep durations may not be indicative of better sleep quality