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A New Transition Metal Borate, Co\u3csub\u3e6\u3c/sub\u3e(B\u3csub\u3e24\u3c/sub\u3eO\u3csub\u3e39\u3c/sub\u3e(Oh)\u3csub\u3e6\u3c/sub\u3e(H\u3csub\u3e2\u3c/sub\u3eO) \u3csub\u3e6\u3c/sub\u3e·2.21H\u3csub\u3e2\u3c/sub\u3eO, Synthesized via a Mild Hydrothermal Synthesis
No full textA new transition metal borate hydrate, Co6B24O39(OH)6(H2O)6·2.21H2O, was synthesized via a mild hydrothermal method using boric acid as the melt. The compound crystallizes in the trigonal space group P 3‾ with lattice parameters a = b = 13.17840(10) Å, c = 12.3287(2) Å, and a unit cell volume of 1854.27(4) Å3 (Z = 2). This borate hydrate crystallizes in a new structure type comprised of layers containing [BO3] trigonal planar units and [BO4] tetrahedra that are linked by CoO6 and Co(OH)2(H2O)4 octahedra via corner-sharing. The crystalline phase was confirmed by powder X-ray diffraction, while single-crystal X-ray diffraction was used to determine the structure. The structure contains eight crystallographically independent boron atoms that connect to each other and form a Fundamental Building Block (FBB) consisting of two triborate rings [B3O7OH] and two [BO3] trigonal planar units connected via corner-sharing. This FBB can be written as 8: ∞2[2(3:Δ + 2T) + 2(1:Δ)]. Optical and magnetic measurements, as well as thermal analyss, were carried out to characterize the new borate
Synthesis of a Series of Rare-Earth-Based Multi-Anion Chalcogenide Iodides Re\u3csub\u3e3\u3c/sub\u3eSi\u3csub\u3e2\u3c/sub\u3eSe\u3csub\u3ex\u3c/sub\u3eS\u3csub\u3e8-\u3ci\u3ex\u3c/i\u3e\u3c/sub\u3ei (RE = La, Ce, Pr, and Nd) Using the Flux-Assisted Boron-Chalcogen Mixture Method
No full textSingle crystals and polycrystalline powders of rare earth mixed chalcogenide iodides La3Si2Se1.21S6.79I, Ce3Si2Se1.39S6.61I, Pr3Si2Se1.22S6.78I, and Nd3Si2Se1.18S6.82I were prepared using the reactive flux-assisted boron-chalcogen mixture (BCM) method at 850 °C. All compounds crystallized in the monoclinic crystal system, space group C2/c (space group number 15). The series adopts the La3Si2O8Cl structure type, containing isolated SiQ4 tetrahedra connected by REQ8 (RE = La, Ce, Pr and Nd) polyhedra; this arrangement creates tunnels that are filled by I atoms. The partial substitution of S by Se was carried out to modulate the optical properties. Phase pure samples and uniform solid solutions were obtained for all compositions as determined using powder X-ray diffraction patterns. Polycrystalline powders were used for physical property measurements, including magnetic susceptibility and UV-Vis diffuse reflectance. The solid-state UV-Vis data for the polycrystalline La3Si2Se1.21S6.79I, Ce3Si2Se1.39S6.61I, and Pr3Si2Se1.22S6.78I samples revealed band gaps of Eg = 2.5(1), 2.2(1), and 2.3(1) eV, typical of semiconductors. Magnetic measurements indicated that Ce3Si2Se1.39S6.61I and Nd3Si2Se1.18S6.82I exhibit paramagnetic behavior with slightly negative Weiss constants θ = −25 and −38. The photoluminescence spectrum of Ce3Si2Se1.39S6.61I exhibits a broad emission band around ∼493 nm
Spatiotemporal Modeling of Maternal Mortality in South Carolina 2018-2023
No full textMaternal death serves as a public health indicator due to fact that it is considered preventable with the availability of modern biomedicine, however, it persists broadly throughout the United States. Current literature outlines national trends in maternal mortality with complicating, preexisting conditions, and structural upstream factors often cited as being the largest contributors to increased risk. This study utilizes publicly available, county-level data for maternal death in addition to demographic and descriptive data in order to estimate maternal mortality rates in each of South Carolina’s 46 counties from 2018 to 2023. In order to address sparsity in the outcome variable and interval censoring for counts 1-9 within the CDC’s publicly available data, an interval-censored, spatiotemporal Bayesian hierarchical model is deployed with Markov Chain Monte Carlo methods utilized in estimating posterior distributions. The model found no significant regression coefficients; however, a few significant spatiotemporal random effects indicate that maternal death rates vary across time and county due to the influence of space and time. Estimated rates showed an increased risk of maternal mortality during the year 2020 and around the lower Midlands, lower PeeDee, and upper Lowcountry regions. K-means clustering separated counties over time into low, medium, and high-risk categories. These clusters had significantly different means for the percentage of individuals on government assistance within the cluster, proportion of Black residents and proportion of Hispanic residents, Gini coefficients, and the percentage with health insurance found through ANOVA testing. This supports prior literature, demonstrating the impact that structural inequities, specifically across race, have on the rate of maternal mortality in South Carolina
The Evolution of the Second Amendment and the American Gun Violence Epidemic: A Historical Analysis of Political Self-Sabotage
No full textFrom the conception of the Bill of Rights until the 21st century, the Second Amendment was read and understood by the American population, both ordinary citizens and government officials, branches, and agencies inclusively, to allow the nation to have an armed military but not for private citizens to own and/or carry firearms. Since 2008, however, the Second Amendment has been interpreted as an absolute freedom for private citizens to own and carry semiautomatic assault weapons in the name of personal protection. This thesis holds that the evolution of society’s attitude on guns and gun control is specifically denoted by the landmark Supreme Court decision in District of Columbia v. Heller (2008), which flipped the precedential interpretation of the Second Amendment. Further, this new view of the right to bear arms has limited Congress’ ability to enact federal gun control, which in tandem have contributed to the current epidemic of mass gun violence.
This thesis aims to disprove popular arguments against gun control, which include that: 1) under an originalist interpretation of the Second Amendment, there is an implied individual right to bear arms; 2) gun control unconstitutionally restricts the right to bear arms; and 3) the mass shooting epidemic is an unfortunate yet inevitable consequence of the freedom to bear arms. By tracing the history of federal gun control and Second Amendment jurisprudence, this paper will demonstrate that: 1) an originalist interpretation of the Second Amendment and its legislative tradition refutes individual-rights interpretations; 2) the regulation of guns is not an infringement of the right to bear arms; and 3) epidemic mass gun violence is not inevitable, as federal intervention from the Legislature and Judiciary has been enacted and upheld specifically to mediate the issue of mass gun violence
The Expanse: Exploring Comparative Mythology in the Mediterranean through Video Game Development
No full textThis web application, titled The Expanse, explores the arguments surrounding comparative mythology, specifically regarding those in the Mediterranean region. The Expanse is a turn-based role-playing game using the characters and gameplay format of the Shin Megami Tensei video game series. The game depicts the conflict between comparativists and particularists using mythological characters, creating situations in which the player takes sides in a debate that permeates the real world. This story seeks to inform players of the subjective nature of sciences by tying moral dilemmas into an overarching metanarrative specific to comparative mythology
Hungry Minds: Analyzing the Impact of Food Insecurity and Food Assistance Programs on Neurocognitive Development and Childhood Mental Health
No full textIntroduction: Food insecurity affects millions of children in the United States and is increasingly recognized as a significant risk factor for poor nutritional intake and adverse health outcomes. However, less is known about how the experience of food insecurity disrupts healthy development and well-being, particularly among American youth. This thesis had two aims: (1) to examine the relationship between household food insecurity and children’s neurocognitive and mental health outcomes and (2) to evaluate how major food assistance programs address, or fail to address, these developmental risks.
Methods: This thesis uses a mixed-methods approach, integrating a narrative literature review, a cross-sectional analysis of 5,494 children aged 5-17 years from the 2022 National Health Interview Survey (NHIS), and a landscape assessment of the Supplemental Nutrition Assistance Program (SNAP), the National School Lunch Program (NSLP) and School Breakfast Program (SBP), and SNAP-Education (SNAP-Ed). In the quantitative analysis, household food security was categorized in two ways: four USDA levels (high, marginal, low, very low) and a dichotomous measure (food secure vs. food insecure). Child outcomes were measured using the Strengths and Difficulties Questionnaire (SDQ), caregiver-reported neurodevelopmental diagnoses, and functional limitations measured by the Washington Group Child Functioning Module (CFM). Multivariate logistic regression models were adjusted for key demographic and contextual covariates.
Results: The literature indicates that food insecurity is consistently associated with internalizing and externalizing disorders, developmental delays, and poorer cognitive and academic outcomes, through pathways involving both nutritional deficits and chronic psychosocial stress. At the same time, studies reveal that protective factors such as social support, community-based initiatives, and resilience can promote optimal development. Quantitative findings show a clear dose- response relationship in which worsening household food insecurity is linked to significantly increased odds of SDQ difficulties, neurodevelopmental conditions, and functional impairment. Finally, the landscape assessment indicates that existing food assistance programs may improve diet quality, food security, and provide meaningful protection against the psychosocial consequences of food insecurity. However, their impact is limited by insufficient benefit amounts, coverage gaps, and environmental barriers that restrict opportunities for healthy eating.
Conclusions: The evidence presented here demonstrates a clear association between household food insecurity and a broad spectrum of adverse psychosocial and neurodevelopmental outcomes. Implications for policy and practice include raising SNAP benefits, universalizing school meals across the full day and year, pairing SNAP-Ed with structural purchasing incentives and community delivery, and incorporating validated measures of children’s psychosocial and mental health outcomes into routine program evaluations. These findings are relevant to current debates in public health, education, and social policy by translating evidence into actionable design changes that can improve immediate child well-being and mitigate long-term consequences
Structural Investigation of Six Quinary Sulfides Synthesized via the Flux-Assisted Boron-Chalcogen Mixture (BCM) Method: Eu2+Containing Members of the RE3MTQ7(M and T = Transition or Main Group Metals, Q = Chalcogens) Family
No full textA series of six quinary rare-earth sulfides Ce1.854+Eu1.152+Na0.30SiS7, Ce1.914+Eu1.092+K0.18SiS7, Ce1.964+Eu1.042+Rb0.08SiS7, Ce1.984+Eu1.022+Cs0.05SiS7, Ce1.974+Eu1.032+Ag0.06SiS7, and Ce1.504+Eu1.502+CuSiS7were obtained in an alkali iodide flux using the boron-chalcogen mixture (BCM) method. Single crystal X-ray diffraction was used to determine the structures of the high quality single crystals that were grown; their elemental compositions were confirmed by energy-dispersive spectroscopy (EDS). The compounds crystallize in the hexagonal crystal system in the noncentrosymmetric space group P63. The crystal structure consists of a three-dimensional network composed of mixed cerium and europium bicapped trigonal prisms, isolated SiS4tetrahedra, and monovalent metals (Na, K, Rb, Cs, Ag, and Cu) located in cavities created by linked Ce/EuS8polyhedra. The structures are charge-balanced when Ce and Eu are in their +4 and +2 oxidation states, respectively. The effective magnetic moment of Ce1.504+Eu1.502+CuSiS7determined from the temperature dependence of the magnetic susceptibility data is consistent with the presence of Ce4+and Eu2+. Clear correlations between the alkali ion site occupancy, the ionic radius of the alkali cations, and the average bond length of Ce4+/Eu2+–S, were established. UV–vis diffuse reflectance data were collected for Ce1.504+Eu1.502+CuSiS7and a band gap of 1.9(1) eV was established
James Kelman and the Impossibility of Managerial Souls
No full textDiscusses James Kelman\u27s portrayal of middle managers and their interactions with those they manage in The Bevel\u27 (1983), A Disaffection (1989), How Late It Was, How Late, (1994), and You Have to be Careful in the Land of the Free (2004), exploring their interactions with those they manage in terms of managerialism, management theories, and the U.K. government\u27s New Public Management reforms
\u3ci\u3eTranscrite Par L\u27Auteur\u3c/i\u3e: Analyzing and Performing the Piano-Vocal Scores of Maurice Ravel\u27s Operas
No full textThe two operas of Maurice Ravel, L’heure espagnole and L’enfant et les sortilèges, are, like most of the composer’s works, known for their innovative orchestrations and instrumental flourishes. However, the piano-vocal scores of the operas have their own unique qualities worthy of study. With the piano writing at times fiendishly difficult—standing toe-to-toe with Ravel’s solo piano music—the score demands simplification, particularly for less experienced performers serving as accompanist or rehearsal pianist for these works. Many sections of the music are impractical or even impossible for a single pianist to perform, but this study offers alternate solutions and simplifications for pianists who are performing these works (in full or in excerpt) or playing the vocal scores as rehearsal pianists. Additionally, this study offers such pianists brief historical context for these works and suggestions of other Ravel works for study or listening which can help with stylistic choices
Automated Fiber Placement Laminate Level Optimization: A Physics-Inspired Method to Analyze Through-Thickness Defect Interactions
No full textWith the growing adoption of composite materials in industries such as aerospace, automotive, naval, wind energy, and even sectors like sports and consumer goods, there has been a strong push towards improving manufacturing reliability and productivity. One key method that has gained significant traction is Automated Fiber Placement (AFP), an additive manufacturing technique valued for its precision, efficiency, and adaptability in producing complex composite parts. As industries continue to shift from traditional metal-based structures to more advanced composite materials, the need for efficient and high- quality manufacturing solutions has become even more critical, prompting a focus on automation and optimization within the AFP lifecycle. This led to the development of the Computer Aided Process Planning (CAPP) software. The CAPP software aims to support process planners by identifying optimal starting points and layup strategies for each ply. Additionally, Ply-Level Optimization (PLO) seeks to assess ply quality by examining predicted defects such as gaps, overlaps, steering, and angle deviation. Laminate-Level Optimization (LLO) provides a much more demanding task, aiming to minimize defect stacking and promote defect dispersion throughout a laminate, enhancing manufacturing efficiency and part quality. This thesis proposes a novel approach for AFP process planning, providing the framework for integration within the CAPP software, enabling users to design and optimize laminate layups based on design criteria, Margin of Safety (MoS), and defect propagation. CAPP integrates defect predictions generated by CGTech’s VERICUT Composite Programming, which are then discretized to simulate through-thickness defect stacking. Additionally, MoS data from Collier Aerospace’s HyperX allows users to tailor laminate designs to meet part specific requirements. Building on this integration, the work in this thesis expands on previous research and introduces a physics-inspired method to analyze defect interactions for AFP Laminate-Level Optimization (LLO). Using a Greedy Search (GS) algorithm coupled with a novel objective function, this approach investigates the optimization of laminate manufacturing of complex geometries, such as doubly curved surfaces. The results demonstrate the ability to produce optimal laminates, enhancing the design-build cycle efficiency and ultimately improving part quality