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Fundamental o Fútil? Relations Between Multiple Dimensions of Familism and Adolescent Sleep in a Hispanic Sample
No full textThe cultural value of familism describes prioritizing family over the individual. Evidence supports relations between familism and health behaviors like sleep; thus, this study explores associations of parent and adolescent familism and adolescent sleep. Latino/a parent-adolescent dyads (N = 438) independently reported on multiple parameters of familism. Objective parameters of adolescent sleep were collected via Fitbit devices. Multiple regression models were fit to determine associations of parent and adolescent familism with adolescent sleep, and the interaction of Parent Familism x Adolescent Familism with adolescent sleep. Youth obligation and parent support familism related to more ideal sleep, while youth referent and parent obligation familism related to less ideal sleep for youth. While some aspects of familism may pose a risk for poor sleep, others support ideal sleep and should be emphasized within the parent-adolescent relationship. As parents and youth cultivate a supportive environment through familism values, youth will experience better sleep
Using Her Words: Marriage in Twentieth Century Advice Columns
No full textThis thesis examines the evolution of popular perceptions of marriage in the United States during the mid twentieth century through advice columns. It argues that the point at which a marriage was considered salvageable drastically shifted between the 1940s and 1950s, which directly correlated with the social markers of success within a relationship. In the 1940s, a marriage was considered successful if the couple was happy and a divorce, though not ideal, could be an option for an unhappy couple. In the 1950s, a marriage was considered a success if the couple remained married for their entire lives, even if they would prefer to be separated. This thesis focuses on “If I Were In Your Shoes,” written by self-proclaimed psychic Gene Dennis for The Seattle Star from 1940 to 1944, and the first four years of “Can This Marriage Be Saved?” which ran in The Ladies’ Home Journal using accounts of the counseling sessions conducted by the American Institute of Family Relations
Mesophication in Southeastern U.S. forests: drivers of flammability and strategies for tree regeneration success
Get PDFDecades of fire exclusion in historically fire-dependent forests across the southeastern U.S. have caused various ecological consequences, including the transition of open-structured forests to closed-canopy forests. This process involves the encroachment of often shade-tolerant, fire-sensitive, and/or opportunistic species, which leads to a decline in flammability, light availability, and subsequent replacement of shade-intolerant and/or fire-tolerant species. This phenomenon, known as mesophication, establishes a self-reinforcing feedback cycle in which the accumulation of encroaching vegetation further suppresses fire by creating cooler, moister understory conditions. Prescribed fire and mechanical thinning are often used to halt or reverse mesophication, though their effectiveness may vary. This dissertation comprises a series of studies examining the effects of mesophication on flammability, tree regeneration, functional mechanisms of persistence in competing hardwood species, and the effects of natural canopy disturbance on fuel characteristics and fire behavior. In the first study, we conducted experimental burns to evaluate how the progressive replacement of longleaf pine (Pinus palustris) by sweetgum (Liquidambar styraciflua) across a gradient of canopy cover affected fuelbed flammability, and survival and growth of species with different fire and shade tolerances. We found a significant reduction in flammability as the pine fuel component decreased below 30%, an effect that was further pronounced with increasing in canopy cover. Additionally, seedling survival was high regardless of species fire tolerance, with sweetgum exhibiting the highest survival across treatments and species. In the second study, we examined how above- and belowground traits of three hardwood species—red maple (Acer rubrum), sweetgum, and southern red oak (Quercus falcata)—responded to varying fire-return intervals and canopy structure. Our findings revealed higher trait plasticity in sweetgum, shown by shifts in non-structural carbohydrates and SLA, and a generalist strategy in red maple compared to southern red oak, regardless of fire frequency or canopy structure. In the third study, we assessed the influence of natural canopy disturbances such as hurricanes and natural tree mortality on fuelbed characteristics and fire behavior in two contrasting fire-dependent forest types: an upland hardwood forest and a longleaf pine woodland. Our results revealed significant effects of canopy loss on fuelbed characteristics in both forest types. Although canopy disturbances had no significant impact on fire behavior in the longleaf pine woodland, fire behavior in canopy gaps within the hardwood forest was more intense than non-disturbed areas. This dissertation contributes to a deeper understanding of the consequences of mesophication on forest flammability, explores functional mechanisms of encroaching species’ persistence, and informs our understanding of the effects of canopy disturbances on fuelbed characteristics and fire behavior across different fire-dependent forests
Experimental Behavior of Skewed Cast-in-Place Concrete Box Culverts
No full textCast-in-place reinforced concrete box culverts are widely used for roadway drainage and are the most common type of bridge in many states. The current culvert design methodology is performed in accordance with the AASHTO LRFD Bridge Design Specifications. However, there is no specific guidance for skewed culverts, where the culvert and roadway centerlines are not perpendicular. Due to the lack of explicit provisions for skewed culverts, state departments of transportation (DOTs) adopt conservative design practices and vary extensively, highlighting the need for consistent design approaches. This study investigates the structural effects of skew angle on cast-in-place concrete box culverts through full-scale laboratory tests.
Three culvert specimens with 10 foot clear spans, identical reinforcement layouts, and skew angles of 0 degrees (control), 30 degrees, and 60 degrees were constructed and tested under simulated vehicular loading. Experimental results revealed that the skew angle had minimal impact on the overall stiffness, service-level behavior, and ultimate strength of the culvert. All specimens displayed nearly rigid slab-to-wall joint behavior, validating rigid assumptions commonly used in analysis. Cracking was not observed at service design load levels, and ultimate load capacities significantly exceeded AASHTO LRFD requirements. The skewed culverts exhibited beneficial two-way bending behavior, engaging both longitudinal slab reinforcement and integral parapet beams, enhancing load distribution. Differences in failure modes emerged at high skew angles, transitioning from beam shear failures at 0° and 30° to slab punching shear at 60°, highlighting the importance of detailing in highly skewed configurations.
This research demonstrates that current conservative practices, such as doubling reinforcement at skewed regions, are unnecessary. A standard, uniform reinforcement design adequately meets structural demands for skewed culverts, offering DOTs opportunities to optimize designs and achieve significant material and cost savings without compromising structural performance
Position Estimation of Multiple Signal Sources in Short Baseline Environments Using Time Difference of Arrival and the MUltiple Signal-source Cross-correlation based Location Estimation (MUSCLE) Algorithm
Get PDFThis thesis uses time difference of arrival (TDoA) measurements to obtain position solutions for multiple radio frequency (RF) signal sources in short baseline environments. Details for TDoA generation are provided along with analysis of how this measurement is challenged by both multiple signal sources and short baseline environments. The MUltiple Signal-source Cross-correlation based Location Estimation (MUSCLE) algorithm is introduced as a novel method to position multiple signal sources using TDoA. This algorithm incorporates maximum likelihood estimation (MLE), combinatorics simplifications to the solution space, and K-means machine learning to extract multiple position solutions. To test this algorithm, a simulation space is created and fully detailed. This simulation is used to test a wide range of algorithm applications without the limitations of hardware setup. Results for the MUSCLE algorithm are applied to several simulation scenarios including an ideal scenario, varied signal sampling rate scenarios, and varied receiver geometry scenarios. The ideal scenario shows that the MUSCLE algorithm can locate all signal sources in a 30x30 meter environment to less than 0.4 meters of error. The varied sample rate test shows that the algorithm can obtain position solutions down to a sample rate as slow as 50 MHz, with faster sampling rates having improved performance. The varied receiver geometry tests show that the algorithm can successfully position when receiver geometry becomes degraded, when the number of receivers is decreased leading to system observability degradation, and when an excess of information is provided to the system. The MUSCLE algorithm is then tested in a hardware-in-the-loop (HWIL) setup where simulated data is transmitted through one Universal Software Radio Peripheral (USRP) device and received by a second USRP. This HWIL data is then used for positioning with the MUSCLE algorithm and compared to the same environment fully in simulation. The HWIL test shows that real received data can arrive at a solution of less than 1 meter error for all signal sources. The simulation and HWIL tests validate that the MUSCLE algorithm successfully determined the position of multiple RF signal sources in short baseline environments
On the overarm throw: Evaluating technique with a novel metric for performance.
No full textThrowing is a highly complex movement pattern. Being refined over millennia (Lombardo & Deaner, 2018a), the body of research surrounding the throwing motion is extensive. However, a predominant focus on baseball pitching may have led to a distortion in the way we interpret similar throwing skills. Furthermore, performance is often considered as ball velocity, or accuracy, with the two rarely being considered together. The aim of this work was, therefore, to investigate the throwing skill in a more general context, and develop a measure for performance that incorporates both ball velocity and throw accuracy. Aim 1 sought to establish the movement patterns utilised for this general throwing skill. Kinematic data for 28 experienced positional baseball players revealed that the pattern of movement was largely similar to that which has previously been reported for American football (Fleisig et al., 1996b) and handball (van den Tillaar et al., 2011). Initial rotations away from the target were followed by rapid accelerations towards it, with joint angles and velocities comparable to these similar skills. Stride length was considerably shorter at 34-38% standing height than had previously been described, suggesting that participants may have adapted their movement due to task constraints (Cook et al., 2000). Coefficient of variation analysis later indicated that the early establishment of a stable throwing foundation is key. Lower-extremity kinematics generally varied less during this time, with variability in distal kinematics reducing as the motion progresses. Aim 2 sought to develop and validate the accuracy-integrated metric (AIM) for objectively evaluating throwing performance. AIM demonstrated a capability for considering all aspects of the throw, and was therefore deemed a viable option for evaluating throwing performance. Weightings for ball velocity, accuracy, and throw distance ensured that faster, more accurate, or longer throws were rewarded providing other aspects remained the same. Consequently, a holistic assessment of any given [throwing] movement pattern should now be possible. The final part of this work sought to identify relationships between technique characteristics and AIM. A mixed-model analysis revealed that only forward trunk flexion at ball release (BR) was statistically related to AIM score, however, it appeared to lack practical significance. For every 1° increase in trunk flexion, AIM score was only expected to increase by approximately 1 point. It was, therefore, concluded that additional variables might better explain AIM than those included in the present work. As such, these should be considered in future investigations of throwing performance. A foundation for future throwing research to build upon, and a performance metric for objectively assessing performance has been provided. It is hoped that these approaches will be adopted in a variety of sports where velocity and accuracy are key components of performance
Immersion Aeromonas spp. vaccine efficacy and coinfection dynamics in largemouth bass (Micropterus nigricans)
No full textThe largemouth bass (LMB; Micropterus nigricans) is a North American freshwater fish species. These fish have gained the reputation of being one of North America’s most beloved freshwater sportfish species and, in recent years, have become a species of interest in the aquaculture division. As consumers highly seek after the white fillets of this fish, the demand for retail LMB is increasing exponentially, creating a drive for aquaculturists to expand production operations. Current aquaculture practices involve highly intensive systems with dense populations of fish. Due to the inherent stressors of culture operations compared to naturally extensive systems, LMB become highly susceptible to pathogen outbreaks, often resulting in mass mortality and production losses to farmers. Motile Aeromonas septicemia (MAS) is a devastating disease from one of three species in the genus Aeromonas: A. hydrophila, A. sobria, A. caviae, and A. veronii. Geographically, MAS cases have been documented throughout the United States and globally. As these cases continue to spread and more aquaculturists expand into LMB production, a greater need arises for a solution to prevent further loss. Current therapeutants in LMB culturing involve the use of salt, formalin, prebiotics, probiotics, and emerging vaccination research. While the field of vaccination in Micropterus nigricans is novel, the requirement for remedy increases with the addition of LMB in farms across the United States and internationally
Optimizing Flight Parameters for Pesticide Application Using Unmanned Aerial Application Systems (UAAS) in Vegetable Production
Get PDFUnmanned aerial application systems (UAAS) are emerging as an alternative technology for precision pesticide applications, addressing challenges in spray coverage and efficiency, particularly in crops with dense canopies such as tomatoes. This research aimed to optimize UAAS flight parameters by evaluating the effects of flight speed, droplet size, and application volume on spray deposition. Field trials assessed coverage, droplet density, deposition, and swath uniformity across different application settings and canopy positions. Results indicate that slower flight speeds (4 m/s) and higher application volumes (28 L/ha) increased coverage and droplet density, while optimal swath uniformity was achieved at 7.93 m/s with 350 μm droplets. In tomato trials, finer droplets improved deposition in the lower canopy, whereas medium-sized droplets maintained uniform distribution. Findings highlight the importance of adjusting UAAS parameters for improved efficiency and targeted applications, contributing to sustainable pest management in specialty crops
The System Works as Intended Alabama’s Property Tax and Public School Systems, 1854-1983
No full textThis study examines the intertwined development of Alabama’s property tax
system and public school system from 1854 to 1983, arguing that fiscal policy served as a
crucial tool of massive resistance to civil rights gains in public education. While the
traditional civil rights narrative characterizes massive resistance as a reaction to Brown v.
Board of Education (1954), this study demonstrates that Alabama’s white elites began
crafting policies to entrench racial and economic inequality long before formal
desegregation efforts. Shortly after Redemption, policymakers embedded fiscal
mechanisms into the 1901 Alabama Constitution to preserve white political and economic
power, restricting Black access to equitable education while shielding white property
from taxation. Throughout the 20th century, Alabama’s legislature responded to civil
rights advancements through fiscal policies that systematically lowered property tax
revenue, removed the state's responsibility to support public education, and stripped local
officials of the power to alter tax structures. By embedding racial discrimination within
the tax code, Alabama’s white elites weaponized the ideology of “taxpayer citizenship” to
frame resistance to equitable school funding as a defense of property rights rather than an
explicitly segregationist project. While courts later acknowledged the discriminatory
intent behind Alabama’s property tax system, they repeatedly refused to mandate reform,
ensuring that underfunded public schools—particularly in majority-Black communities—
remained a lasting legacy of Alabama’s fiscal resistance to federal demands for equality.
This study reframes the history of segregated schooling by demonstrating that property
tax policy functioned as a durable and legally sanctioned mechanism of white supremacy,
one that continued to undermine public education and racial equity long after the formal
victories of the civil rights movement
Biochar Influences Soil Health and Nutrient Dynamics in Row Crop Production Systems
No full textMost soils in Alabama are Ultisols, which are characteristically highly weathered, low in organic matter, and inherently low in fertility. The introduction of biochar to these soils as a soil amendment has the potential to increase soil health, which would be beneficial to Alabama producers. Biochar is organic matter that undergoes pyrolysis, resulting in a highly charged, highly stable source of carbon. However, it is an expensive soil amendment, and further research is required to under-stand how biochar will affect soil health and crop production in Ultisols.
An ongoing research study was initiated at both the Wiregrass Research and Extension Center in Headland, Alabama, and the Tennessee Valley Research and Extension Center in Belle Mina, Alabama, to investigate the impact of varying biochar application rates (0, 3.5, 7.0, and 14.0 Mg ha-1) in combination with cover crops on soil health within crop production systems. The study utilized a randomized complete block design with four replications. Soil samples were collected to a depth of 60 cm in spring 2024 and 2025 following the termination of cover crops. Chemical indicators assessed included pH, Mehlich 1-extractable plant nutrients, soil organic carbon, inorganic N, and permanganate oxidizable carbon. Physical indicators measured included bulk density and wet aggregate stability. Biological indicators measured included microbial biomass carbon and soil res-piration. Additionally, agronomic factors such as tissue nutrient uptake and yield were evaluated.
The highest biochar application was observed to have the most influence on soil health pa-rameters. Soil organic carbon in the top 5 cm of soil increased by 64% at WREC and 17% at TVREC when 14 Mg ha-1 biochar was applied. For every 1 Mg ha-1 of biochar applied, carbon sequestration increased by 0.348 Mg ha-1 at WREC and 0.301 Mg ha-1 at TVREC. Minimal effects were observed at deeper depths for both locations. Surface soil pH increased slightly at WREC, but not at TVREC, when 14 Mg ha-1 biochar was applied. A year and a half after application, biochar had minimum influence on soil nutrient content, biological soil properties, and physi-cal soil properties. Biochar did not affect cotton yields at either location; however, cover crops re-sulted in an 8% increase in cotton yield at WREC compared to fallow. Biochar rarely interacted with cover crops to influence soil health indicators and agronomic factors. More time is required to thoroughly investigate the full effects of biochar and its potential impacts on soil health, as well as the effects of cover crops and biochar on soil health