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The Scoop, Vol. 11 Issue 12, March 2025
No full textLatest news and updates from the Health Sciences Library in our monthly newsletter for March 2025. Please see page 2 for a text-only version of this issue!https://stars.library.ucf.edu/scoop-vol11/1010/thumbnail.jp
Spectral Properties of Disjoint Unions of Open Intervals via Unitary Groups of Local Translations
No full textThe connection between spectral properties and tiling properties of domains can be explored by mimicking an early approach of Fuglede. This approach focuses on self-adjoint extensions of differential operators and associated strongly continuous, one-parameter unitary groups. We take this approach in this thesis, determining an explicit formula for such a unitary group and use this to create new connections between spectral and tiling properties of a domain. Dutkay and Jorgensen showed it is enough to consider the case when the domain is a disjoint union of open intervals, so we restrict the scope of this thesis to this case as well. In the first part, we follow the exposition of Dutkay and Jorgensen in the creation of these unitary groups. Each self-adjoint extension of the momentum operator on the domain is simultaneously associated to a unique unitary matrix of boundary conditions and a strongly continuous, one parameter, unitary group. Spectrality of the domain yields a unique spectral boundary matrix and associated unitary group. Not only can the spectrum of a spectral domain be determined with these tools, but this unitary group must be a unitary group of local translation, acting as a translation operator on the domain. This part of the thesis culminates in the development of an explicit formula for the unitary group. The second part of the thesis uses the explicit formula for the unitary group and the local translation property to describe certain geometric properties that spectral domains must possess. Namely, the gap between any two intervals of a spectral domain must be a sum of lengths of intervals in the domain. Moreover, we show that under the additional assumption of multiplicativity of the unitary group, a power of the spectral boundary matrix is forced to be a permutation matrix, yielding questions for future research
Sexual and Gender Minority Identity Acceptance and the Role of Florida Legislation Perception on Medical Disclosure and Risky Health Behaviors
Full text linkRecently, across the United States, efforts have been made to remove protective legislation and resources surrounding the sexual gender minority (SGM) community (Woodford et al., 2018). Given how quickly Florida’s HB 1557 legislation was passed and the corresponding, ongoing attempts to expand the bills, there is limited research exploring the role of legislative change on SGM communities. Newer literature indicates that discriminatory laws or bills have impacted the mental health of the SGM community, especially among SGM adolescent and young adults ; however, research exploring the role legislation has on SGM individual’s physical health, requires further investigation(American Psychological Association, 2023; Noh, 2023; Novotney, 2023). This thesis examined the role that perception of the new legislation and SGM social support plays in SGM health behaviors and SGM identity disclosure. The sample (N= 425) consisted of young adults from a large, Florida, metropolitan university. SGM participants scored significantly higher than non-SGM participants in risk behavior engagement, risk behavior interference, and risk as negative coping behaviors. SGM identity significantly predicted fear of identity disclosure. Negative legislation perception was a significant moderator and predictor of fear of identity disclosure among SGM participants. Fear of disclosure fully mediated the relationship between SGM identity and risk as negative coping behaviors. Social support showed a significant, positive moderating effect between fear of identity disclosure and risk as negative coping behaviors. Further analyses and their implications are discussed
Dynamic Ground Response of Sandy Soils Under Vibratory Roller Compaction
No full textVibratory roller compaction is a common technique for densifying granular materials in road construction, utilizing a combination of static and dynamic loads for greater efficiency. However, the vibrations generated during compaction activities can cause structural damage and human discomfort. This thesis investigates the dynamic ground response of sandy soils under vibratory roller compaction, aiming to predict the induced ground vibrations and deformations. Field tests were performed at different road construction sites in Central Florida by using geophones and settlement transducers to provide empirical support for the analysis. Finite element and finite difference models, implementing Hypoplasticity Sand and PM4Sand as constitutive models, respectively, are compared and validated with field measurements to determine the most suitable framework for simulating this phenomenon. A parametric study is conducted to evaluate the influence of key variables involved in this problem such as the dynamic properties of the roller (i.e., centrifugal force and vibration frequency) and the relative density of the soil. Based on the results, envelopes and prediction equations are developed to estimate ground vibrations and deformations in terms of Peak Particle Velocities (PPVs) and Peak Particle Displacements (PPDs), respectively, under different compaction conditions. These findings contribute to refining standard specifications, mitigating adverse effects while maintaining construction efficiency. Additionally, the study demonstrates that the ground response is highly dependent on the centrifugal force of the roller due to its direct relationship with the energy transmitted to the soil
Insights into Iapodian Lifeways: Phytolith and Starch Grain Analysis of Animal and Human Dental Calculus from Croatia
No full textThe Piplica hillfort is located near the village of Lovinac within the Lika region of Croatia. The Bronze Age is a pivotal period in Europe that encompasses changes in landscapes, social structures, and famously includes vast production of metals. The Bronze Age in Lika is characterized by changes in social, political, and economic lifeways; denser populations; expanded trade networks; and advancements in agriculture, husbandry, and metal-working. However, little is known about the Iapodes people, who inhabited the Lika region during the Late Bronze Age, and how they interacted with their environment.
The Iapodes were only known from classical Greek written sources until excavations beginning in the 19th century. The Iapodes left material culture including ceramics, amber, metalwork, and glass but also animal bones and plant remains. However, poor preservation of paleobotanical remains does not allow us to know much about Iapodian agricultural practices. This project intends to contribute to the paleoethnobotanical knowledge of Croatia and provide insight into Iapodian lifeways. Paleoethnobotanical and zooarchaeological methods were utilized to analyze 20 animal teeth and eight human teeth provided by Dr. Emily Zavodny. Dental calculus from the teeth was scraped off and processed in Dr. Neil Duncan’s Paleoethnobotany and Environmental Archaeology Laboratory (PEAL) for phytolith and starch grain analysis. A single unidentifiable starch grain was found after processing. Further testing of phytolith and starch grain extraction from animal and human dental calculus is suggested to continue building on paleoethnobotanical knowledge of the region. Complementary methods such as microwear analysis, residue analysis, and sediment analysis are recommended to provide additional means of gathering context and data in future studies
The College Admission Genre: A Deep Dive into Student Identity and the Impact of Creative Nonfiction on College Admission Essays
No full textThis exploratory case study was conducted to determine the connection between student writing identity and how writing identity, if at all, ties into how well high school students write narrative essays when applying to college. As upperclassmen students in high schools across the country determine their post high school path, many students are required to write college admission essays and scholarship applications. These essays, often classified as narrative writings, can often be difficult for students if they are not explicitly taught the nuisance of audience and style these essays rely on. This study utilizes research on student writing identity and how students interact with narrative style writing tasks while taking a closer look at writing samples from junior students in an AVID 3 course within the AVID Program from the 2023-2024 school year. This research is significant because it provides a relevant analysis of how current high school students respond to college writing prompts without explicit instruction
Study of the superconducting and normal states properties of topological nodal-line semimetals
No full textTopologically protected quantum computation is getting great interest due to its potential use in creating fault-tolerant quantum computers. Using quasiparticle excitations known as non-Abelian anyons, which obey non-Abelian braiding statistics, is the way to perform topological quantum computation. A topological superconductor has protected gapless states on its boundaries while maintaining a superconducting gap in the bulk, and predicted to host Majorana fermions which are non-Abelian anyons. Although several theoretical models propose systems with non-Abelian anyons, px + ipy wave superconductors in which vortices exhibit non-Abelian braiding statistics is one of the most realistic physical systems. Realizing physical systems with non-Abelian anyons is one of the frontiers in recent theoretical and experimental research works. Therefore, in this thesis, we studied predicted superconducting topological nodal-line semimetals to realize possible topological superconductivity, flat energy bands and the effect of spin orbit coupling, in the normal and superconducting states.
To investigate the topological nature and superconductivity, we synthesized Sn0.15NbSe1.75 single crystals using the self-flux method and studied the normal and superconducting state properties of Sn0.15NbSe1.75 (Tc = 9.5 K) using soft-point-contact spectroscopy. We observe asymmetric double peaks in the normal state differential conductance dI/dV due to the Fano resonance as a result of quantum interference between two distinct tunneling paths of transmitting electrons into flat energy bands and dispersive bands. Hybridization between these bands below the hybridization temperature Thyb = 23 K is realized according to a phenomenological double Fano resonance model. A pseudogap below a characteristic temperature TPG = 6.8 K is also observed due to the hybridization between these bands. We observe an unusual linear in T behavior in the upper critical field from 0.4Tc to 0.01Tc, indicating a possible exotic superconducting state. Our results indicate the presence of surface flat energy bands and hybridization between the surface flat bands and the bulk bands in Sn0.15NbSe1.75.
To clarify the effect of spin orbit coupling on superconductivity, we studied the normal and superconducting state properties of Pb1-xSnxTaSe2 (0 ≤ x ≤ 0.23) single crystal synthesized by chemical vapor transport technique. Substituting Pb with Sn enhances the superconducting transition temperature Tc up to 5.1 K and also significantly increasing impurity scattering in Pb1-xSnxTaSe2. The normalized specific heat jump at Tc for x = 0 and 0.018, exceeds the Bardeen-Cooper-Schrieffer (BCS) predicted value of 1.43 for the weak-coupling superconductor. This observation indicates the possible strong-coupling superconductivity in undoped and slightly Sn-doped PbTaSe2. A single-gap model cannot explain the observed specific heat jump at Tc that is smaller than the BCS value of 1.43 for moderately Sn-doped samples. A two-gap model excellently reproduces the observed specific heat data of moderately Sn-doped (x = 0.08 and 0.15) PbTaSe2. Our observations suggest that the multiband effect increases the effective electron-phonon coupling strength, giving rise to an enhancement in Tc of Pb1-xSnxTaSe2
Using Unmanned Aerial Vehicles (UAV) and Closed-Circuit Television (CCTV) Video for Multi-Object Multi-Camera Vehicle Tracking (MOMCMVT) in Traffic Monitoring
No full textThis study integrates Unmanned Aerial Vehicles (UAVs) and Closed-Circuit Television (CCTV) cameras to enhance traffic monitoring through a Multi-Object Multi-Camera Multi-View Tracking (MOMCMVT) framework. By combining UAV and CCTV data, the framework provides a more comprehensive and accurate representation of traffic dynamics. The Automated Roadway Conflict Identification System (ARCIS) is utilized to stabilize UAV footage using the Scale-Invariant Feature Transform (SIFT) algorithm, while the Channel and Spatial Reliability Tracking (CSRT) algorithm ensures robust vehicle tracking in CCTV footage. To address perspective disparities and limited overlapping coverage, perspective transformations and GPS adjustments are applied, aligning image coordinates with real-world locations. The system was evaluated on a 975-meter freeway segment over two days using four UAVs and multiple CCTV cameras. Experimental results indicate high accuracy in vehicle detection and tracking, achieving an F1 score of 0.869 and accuracy of 0.909 for overlapping coverage, and an F1 score of 0.9478 with accuracy of 0.9009 for non-overlapping coverage. These findings demonstrate the effectiveness of integrating UAV and CCTV data for large-scale traffic monitoring, offering improved vehicle tracking and reallocation across multiple camera views. The proposed approach enhances real-time traffic management, congestion analysis, and safety assessment by providing reliable and precise vehicle movement data. This research contributes to advancing multi-camera multi-view tracking methodologies, offering a scalable and adaptable solution for traffic surveillance. The integration of UAV and CCTV data presents a promising direction for improving traffic monitoring accuracy and efficiency, with potential applications in intelligent transportation systems and smart city initiatives
On The Dynamic Connectivity And Phase Transition In River Networks
Full text linkRiver network (RN) structure has a significant impact on flux transport, aggregation and ecosystem connectivity. In this dissertation, the structural control of RN on flux transport was investigated by the application of integrated framework of dynamic clusters and network graph theory. This new framework has been proposed to determine sub-catchment connectivity using minimum and maximum flow criteria. Our analysis on synthetic and natural RNs across United States demonstrates that basin scale connectivity at low flow conditions is efficiently governed by the abundance of side branching junctions whereas this characteristic slows down the flux convergence rate at maximum flow condition.
Furthermore, our study identifies the existence of a phase transition in which aggregation of flux condition shifts from a scattered state to a congested regime during downstream flux movement. Our analysis on natural RNs from different climatic regions reveals an interesting relationship between the critical distance—defined as the distance that fluxes travel from the sources when the phase transition occurs—and climate. The findings of this study indicate that the timing of this transition is influenced by the climate, with humid basins undergoing earlier phase transition due to the higher density of side tributaries. These results suggest that the RN topology intrinsically governs the climate dependence of transport dynamics.
Finally, we investigated the impact of transport dynamics in river delta evolution. River avulsion—abrupt channel jumping—and lateral channel migration are closely linked to flux transport and shape landscape over different time scale. The results based on the data analysis collected from depositional system-based experiments exhibit the distinct signature of avulsion and lateral migration on deltaic topography
Evolving Perceptions of Self and Others: The Effects of Communing with Nature While Thru Hiking the Florida National Scenic Trail
No full textThis body of artwork comprises a thesis that documents and exposes the artist’s inner workings as she regained balance after experiencing deep emotional trauma. This individual’s healing transformation was prompted by her immersion in nature while walking the Florida National Scenic Trail in its entirety, 1,130 miles (or 1,818 km), from the Everglades to the panhandle, in three and a half months. The artistic research conducted, and autobiographical body of work created from it, aims to help others reconnect with their own strengths and to seek wellness in the restorative properties of Nature, while advocating for an empathetic approach to modern advancement. This approach respects the Self, others, Nature, and all creatures as an entity, each an essential component of a large ecosystem