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Don’t miss our latest research from our current issue, featuring: Parental Expectations of Pediatric Care for Children by Brenan T. Cash, Jacquelyn D. Wiersma-Mosley, Donia Timby, and Laura Herold
No full textBrenan Cash on Floreana Island in the Galapagos Islands, where he studied the economy, animals, and history of the islands and Ecuador.https://scholarworks.uark.edu/discovery_images/1059/thumbnail.jp
Contextualizing Egyptian-Themed Art in Pompeiian Shops
No full textThis project focuses on the art historical, architectural, and archaeological evidence outside the domus to investigate the multivalent messaging communicated by Egyptian imagery in Pompeii’s civic and commercial spaces. By examining the artifacts and images commissioned by traders and craftsmen in their production and shop spaces, this research offers a bottom-up approach to Roman culture and society to balance the textual based top-down perspective that has dominated the discipline. Focusing on foreign-themed objects and images in these spaces, this study also explores the reception and adoption of foreign/eastern influences by the lower social strata of Romans in a multiethnic empire
Retelling a Tale in Pictures: A Fusion of the Arts in a Medieval Emaki of the Japanese Court Romance Geni npo monogatori Tale of Genji
No full textThe Genji no monoga ta ri 源氏の物語, the Tale of Genji, b y the Japanese court lady Murasak i Shi kibu 紫式部 ( c . 9 7 3 – c . 1014), thought to have been completed around the year 1008, is one literary masterpiece of the Heian 平安 period (794–1185) that has been adapted for retelling many times. A little over one hundred years after its conception it had been adapted and lavishly illustrated as an emaki 絵 or “ picture scroll. This paper provides a discussion on the importance of the emaki to the representation of this early text
Switching Performance Optimization of SiC MOSFETs with Digital Active Gate Drivers
No full textSilicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) have extensive applications in high-power density devices, but they exhibit quick switching transients that are problematic, including electromagnetic interference (EMI), voltage overshoot, and current imbalance between paralleled devices. The purpose of this dissertation is to maximize the switching performance of SiC MOSFETs using digital active gate drivers (AGDs). A three-level gate driving approach is presented to improve current sharing in paralleled SiC MOSFETs through turn-on voltage and gate signal delay adjustment. Closed-loop control with real-time feedback ensures high-reliability operation. For better practicability, a compact AGD structure of a single-path Class-B amplifier-based topology is presented. The structure allows multistage independent control, which makes gate voltage response time 40% shorter while maintaining Miller clamp function without extra circuits. A DSP realization takes the place of FPGA counterparts to reduce system expense and complexity. In addition, a switching-time-dependent sampling technique is introduced to boost high-frequency feedback for digitally controlled power converters. Effective online parameter identification using low-speed ADCs is enabled by the proposed technique, as demonstrated by experimental validation on an SR-DAB converter. By addressing key SiC MOSFET gate driving issues, the work accelerates the development of AGD technology and enhances system efficiency, EMI performance, and reliability in future power electronics. Converters, the approach enables online parameter identification and real-time monitoring of SiC MOSFET performance effectively
Synthesis of Pillar[n]arenes and Bridge-Functionalized Pillar[n]arenes via Cyclic and Acyclic Acetals
No full textPillar[n]arenes are macrocyclic compounds consisting of ‘n’ hydroquinone units linked by para-methylene bridges. Since their first report of facile synthesis 17 years ago, pillararenes have attracted significant interest due to their versatile functionality, electron-rich cavity, crystalline nature, and planar chirality. These unique properties have enabled a broad range of practical applications, including small molecule separation, formation of one-dimensional and two-dimensional channels, drug delivery systems, and enhanced emissive and fluorescent properties. The ease of synthesis of pillararenes has been one of the key factors in their widespread adoption and continued exploration in supramolecular chemistry and material science. Despite the efficiency and broad substrate scope of traditional pillararene synthesis, it relies exclusively on paraformaldehyde as the source of methylene bridges. However, paraformaldehyde releases formaldehyde, a known carcinogen, at ambient conditions causing safety concerns. In this study, we demonstrated that cyclic and acyclic acetals of formaldehyde serve as safer and nonaqueous alternatives to paraformaldehyde. This novel approach preserves the efficiency and simplicity of traditional pillararene synthesis while significantly improving safety by reducing formaldehyde exposure. Using paraformaldehyde for pillararene synthesis does not allow for substitutions on the methylene bridge of pillararenes. This limitation can be addressed by employing acetals. This study demonstrated that using cyclic acetals of acetaldehyde as the bridge source allowed for the synthesis of methyl-substituted-methine-bridged pillar[6]arenes. Notably, introducing a methine bridge introduced chiral centers and shifted the thermodynamic equilibrium towards one stereoisomer of the corresponding pillar[6]arene, providing access to a stereoselective synthetic protocol for pillar[6]arene with an improved yield of 43%. This strategy significantly enhances the safety profile of pillararene synthesis and expands the structural diversity of pillararenes. This broadened diversity could lead to more applications across various fields
Sound Decisions: The Impact of Music Genre in Fashion Advertising on Consumer Perceptions and Purchase Intention
No full textThis study examines how music genre, brand type, and the perceived congruency between the two influences consumer perceptions of fashion advertising. Guided by Congruity Theory and Attitude Theory, this study employed a 3x3 experimental design in which 252 participants viewed one of nine advertisement conditions varying by music genre (pop, hip-hop, electronic) and brand type (activewear, fast fashion, luxury). A series of one-way ANOVAs, bivariate correlations, and regression analyses were conducted to interpret the effects of music genre, brand type, and perceived congruency on attitudes toward 1) the advertisement and brand, 2) credibility of the advertisement and brand, and 3) purchase intention. Results revealed that pop music was the most effective genre in eliciting favorable attitudes, while hip-hop performed the least favorably across consumer outcomes. Additionally, activewear and fast fashion brands elicited more positive responses than luxury brands. Perceived congruency had a positive influence on all consumer outcomes, particularly attitude toward advertisement. Additionally, brand attitude was found to be the most significant predictor of purchase intention. These findings contribute to the literature on music in fashion advertising by demonstrating that the alignment of music genre with brand type significantly enhances advertising effectiveness
Can Shame and Guilt be Used as a Deterrent for Drug Use and Drug Crime Recidivism?
No full textIntroduction: The present study focuses on how shame and guilt can be used as a deterrent for substance use and substance-related crime recidivism. This research is significant because of on-going alcohol and other drug crime recidivism in the United States. About 68% of drug-involved offenders have been found to recidivate within three years of their release from prison. Understanding how guilt and shame affect one\u27s drug use and crime recidivism is important in recovery. This study was influenced by Braithwaite\u27s theory of reintegrative shaming: using shame and guilt as the specific deterrent for recidivism. Methods: Based on this theory, we developed vignettes to manipulate feelings of shame and guilt in the participant as a function of the degree to which the crime was publicly known versus private. Four vignettes are included: 2 drunk-driving (private and public) and 2 driving under the influence of marijuana (private and public), all of which were first piloted with students and experts. After the participant read their randomly assigned vignette, they were asked questions regarding their levels of shame and guilt (5-point scale), and likelihood to use the substance and likelihood to engage in the behavior again (7-point scale). We hypothesized that (H1) elevated levels of shame and guilt would be correlated with lower levels of likelihood to use and likelihood to engage in the behavior again, (H2) public factors would induce more shame than would private factors, and private factors would produce more guilt than public factors, and (H3) public factors would cause decreased likelihood to use and to engage in the behavior again than would private factors. Results: Shame and guilt were negatively correlated with the likelihood to engage in the behavior again, but not likelihood to use the substance again. Public and private factors did not have significant main effects on levels of shame and guilt, and they were not significantly different across substance type conditions. There was no significant main effect on public and privacy factors on the likelihood to use again or the likelihood to engage in the behavior again. Conclusion: Results partially support the hypotheses and Braithwaite’s theory. Future research can continue to understand how these results may differ among individuals with more severe drug-related crimes and use, and among other populations who have interacted with the criminal justice system (i.e., drug court participants, incarcerated adults)
Engineering Properties and Stress-Strain Behavior of BCSA Concrete: Flexural Design Parameters, Strain Measurement Methods, and Models
No full textBelitic calcium sulfoaluminate (BCSA) cement concrete has gained popularity due to advantages over portland cement (PC), including, its fast-setting, high early strength gain, high durability, and reduced global warming potential. Though primarily used for pavement repair, it has good potential for structural applications. Building codes like ACI 318:19 permit alternative cement materials like BCSA cement if they can be shown to have adequate and predictable structural, durability, and fire performance comparable to PC concrete. This study evaluates the structural and mechanical behavior of BCSA cement concrete, measuring standard engineering properties and comparing results to PC concrete and code prediction equations. To assess its performance in reinforced concrete beams, flexural compression specimens were tested using a method replicating the compression stress and strain distribution in a reinforced concrete beam member. Results showed BCSA cement concrete met or exceeded PC performance, and existing code equations for flexural design parameters were adequate or conservative. Engineering properties and stress-strain constitutive behavior were measured across a range of mixtures with varied water cement ratios, and aggregate types, from 4 hours to 6 months of age. Most code equations adequately estimated properties like elastic modulus, modulus of rupture, and tensile splitting strength with acceptable accuracy. New, more accurate equations are proposed for estimating BCSA cement concrete elastic modulus from non-destructive testing. Digital image correlation (DIC) was used throughout this study to evaluate the stress-strain behavior of BCSA cement concrete and PC concrete. A comparative investigation of strain measurement techniques found DIC to be an effective tool for characterizing the full stress-strain behavior and the strain data collected was used for suggesting historical stress-strain constitutive model improvements
The Relationships Between Gendered Microaggressions, Internalizing Symptoms, Burnout, and Patient Care in Female Medical Residents
No full textFemale medical residents frequently encounter gendered microaggressions, but there is limited research on how these experiences relate to psychological well-being, burnout, and patient care. The present study investigated (1) the frequency of gendered microaggressions among female medical residents in the United States and (2) the associations between microaggressions, internalizing symptoms, burnout, and self-reported patient care. After screening for eligibility, 14 verified participants completed an online survey including a modified version of the Microinvalidation and Microinsult Scale-16 (MIMI-16), the Depression, Anxiety, and Stress Scale (DASS-21), the Maslach Burnout Inventory (MBI), and a self-reported patient care scale. Descriptive results showed participants experienced gendered microaggressions slightly more than rarely, with common experiences including comments on one’s appearance more often than men, competency levels being questioned, and differing gendered expectations. Microaggressions were significantly correlated with internalizing symptoms, supporting the hypothesis that more frequent microaggressions relate to higher depression, anxiety, and stress. Although the association between microaggressions and burnout did not reach statistical significance, the medium-to-large correlation (r = .42) suggests a meaningful relationship likely obscured by limited statistical power. Microaggressions were not directly associated with patient care attitudes or practices. However, exploratory analyses indicated a potential serial mediation pathway in which microaggressions relate to greater internalizing symptoms, which in turn relate to higher burnout and subsequently to poorer patient care. Burnout itself was strongly associated with suboptimal patient care practices and attitudes. Findings highlight the emotional burden of gendered microaggressions and suggest possible downstream implications for patient care through increased emotional distress. Due to the small sample size and reliance on self-report data, results are preliminary but underscore the need for larger, multi-site research and institutional interventions to reduce gendered microaggressions and promote resident well-being
Spatial-temporal Analysis of Drought-Pluvial Volatility
No full textClimate change is intensifying the frequency and magnitude of rapid transitions between drought and flood conditions, creating unprecedented challenges for water resource management, agricultural productivity, and ecosystem stability. This dissertation presents a comprehensive, multi-scale analysis of drought-pluvial volatility by 1) examining their observational uncertainties, 2) exploring their agricultural impacts, and 3) investigating landscape controls on these transition events across global and continental scales. Using the Event Coincidence Analysis with multiple observational datasets (GPCC, CRU, ERA5), this research provides a systematic global assessment of drought-to-pluvial (DTP) and pluvial-to-drought (PTD) transition frequencies from 1951-2020. Our results demonstrate that approximately 15.5% of meteorological droughts shift to pluvial conditions at the global scale, with similar rates for the reverse transitions, though substantial regional variations and observational uncertainties exist. In addition, the temporal analysis reveals an increase in drought-to-pluvial frequencies in several regions over the recent decades, with enhanced agreement among datasets for trend detection compared to the absolute frequency estimation. The agricultural implications of these transition events are next examined across the contiguous United States using crop yield data for corn and soybeans from 1980-2016. Our analyses reveal that the DTP events can partially mitigate drought-induced yield losses in the Upper Midwest, while the PTD events consistently exacerbate pluvial impacts, intensifying yield reductions by 10-15% in vulnerable regions, including the Northeast, Ohio Valley, and Southeast. Seasonal timing plays a critical role, with mid-season transitions showing the strongest influence on crop outcomes, particularly for corn during reproductive development phases. The third component of this dissertation investigates relationships between land use/land cover (LULC) patterns and drought-pluvial transition events using four decades of high-resolution satellite data (1985-2024). This continental-scale analysis reveals striking differences between the forest-dominated regions (transition rates \u3c 20%) and the agricultural landscapes (rates \u3e40%), providing empirical evidence for LULC controls on hydrological volatility. Crucially, the research identifies divergent landscape change patterns: regions with low drought-pluvial transition probabilities exhibit gradual, directional vegetation development toward improved water regulation capacity. In contrast, high-transition areas demonstrate chronic vegetation instability and simultaneous opposing land cover conversions (grassland-to-shrubland and shrubland-to-grassland transitions occurring concurrently across different locations) that perpetuates vulnerability of drought-pluvial transition events. This dissertation advances scientific understanding of compound extreme events by quantifying their global patterns, agricultural consequences, and their associations with the landscape. The findings highlight critical observational uncertainties that must be considered in climate model validation and risk assessment. Agricultural analysis shows that drought-to-pluvial events can mitigate drought-induced crop losses, while pluvial-to-drought transitions intensify yield reductions by 10-15% in vulnerable regions. The identification of LULC-hydrology feedback mechanisms provides new insights for developing landscape-based adaptation strategies to enhance resilience under accelerating climate change. In conclusion, these results show that drought-pluvial volatility poses a challenge, requiring integrated approaches spanning observational science, agricultural adaptation, and land management policy