Click on this link to download the full high-definition interactive pdf for AJUR Volume 22 Issue 1 (March 2025). The Crossref link for this issue is https://doi.org/10.33697/ajur.2025.128
Links to individual manuscripts, abstracts, and keywords are provided below.
p. 3. Modeling Recurrent Emergency Room Trends in the United States
Amanda Bair
https://doi.org/10.33697/ajur.2025.129
ABSTRACT: Emergency departments around the United States struggle with staff shortages and overcrowding following the COVID-19 pandemic and resulting shutdowns. This study aims to create and examine models representing the probability of patients requiring multiple emergency department visits during treatment to better understand why some patients require recurrent emergency department treatments. The two models considered in this experiment are the Poisson Process and the “Frequent Flyer” Hypotheses. Ultimately, analyzing the data provided by the National Center for Health Statistics revealed that the Poisson Process does not accurately represent the realities of recurrent emergency department visits, but the “Frequent Flyer” Hypothesis does in some situations. It also revealed that there may be several lurking variables that compound to determine if a patient will require multiple emergency department visits, accounting for the inconsistencies of the “Frequent Flyer” Hypothesis. KEYWORDS: Recurrent Emergency Room Visits; Repeated and Frequent Emergency Department Visitors; Overcrowding; Emergency Department; Poisson Process; Frequent Flyers; Mathematical Modeling; Healthcare Management; Healthcare Outcomes
p. 15. Caregiver Burden in Parents Providing Care for Children with Serious Mental Illness: A Systematic Review and Meta-Analysis
Pariya Chanthasensack, Rachel E. Dinero, Will P. Randazzo, Toviel J. Francis, & Anna E. Swinchuck
https://doi.org/10.33697/ajur.2025.130
ABSTRACT: Aim: The main purpose of this investigation is to explore and identify the factors that contribute the most to the exacerbation of caregiver burden for informal caregivers of individuals with serious mental illnesses (SMIs). Procedure: Literature searches comprised 18 combinations of search terms related to caregiver burden and serious mental illness. Across eight databases, 1532 articles were identified. After removing 596 duplicates, 936 articles were screened for inclusion criteria, resulting in three studies that met the criteria. This small number of articles included were due to the specificity of our inclusion criteria. From these articles, correlations between caregiver burden and any other variable were extracted. Meta-analysis was conducted using a three-level meta-analytic model. Results: A total of five factors were identified across the included articles: parent age, parent education, parent health, social support, and care recipient characteristics. The three-level meta-analytic model identified the factors parent health, (z = .314, CI [.138, .490], se = .074, t(7) = 4.222, p = .004), and social support (z = -.155 CI [-.282, -.027], se = .056, t(9) = -2.750, p = .022), to have significant overall effect sizes. The remaining factors did not yield significant overall effect sizes. Conclusions: This review reveals that there is still limited research on caregiver burden for caregivers providing support to individuals with SMIs, to the level of specificity that accounts for the different relationships in caregiver-care recipient dyads. However, from the data available, variables that had the largest impact on caregiver burden measures were parental health and social support. These aspects may be possible targets for informal caregiver support. KEYWORDS: Caregiver Burden; Caregiver Burnout; Serious Mental Illness; Informal Caregiver; Parental Caregiver; Risk Factors; Systematic Review; Meta-Analysis
p. 27. The Influence of Gender on the Support and Confidence of Students in Undergraduate STEM Majors
Minnatallah Nassir Elsir Eltinay, Danielle E. Lin Hunter, Porché Spence, & Zakiya Leggett
https://doi.org/10.33697/ajur.2025.131
ABSTRACT: Gender can have an impact on the intended career pathways in the science, technology, engineering, and mathematics (STEM) fields. This has important implications for research on gender issues in STEM education in larger contexts. In particular, this is essential to gain a better understanding of gender representation, academic confidence, STEM confidence, and career progression in higher education. Using a quantitative questionnaire-based research design approach, this study analyzes the experiences of undergraduate students currently pursuing and enrolled in STEM disciplines at a four-year land-grant university in North Carolina. With family members, friends, peers, classmates, and professors playing a role in supporting undergraduate STEM students, this data signifies a trend of men/self-identified males (males) demonstrating more confidence than women/self-identified females (females). KEYWORDS: STEM Confidence, STEM Identity; Undergraduate Support; Gender Representation; Gender Identification; Higher Education; Scientific Confidence; Underrepresented Students; Undergraduates
p. 37. In silico Analysis of a Nonsense Mutation Linked to Autosomal Recessive Hypercholesterolemia Type 4
Caroline Gardner & Deborah J. Good
https://doi.org/10.33697/ajur.2025.132
ABSTRACT: Autosomal recessive familial hypercholesterolemia-4 (FHCL4) is a genetic disorder caused by mutations in LDLRAP1, a gene encoding a protein that allows the LDL receptor to be endocytosed and degraded in the liver. In silico tools were used to examine the rs121908325 variant linked to FHCL-4. The variant protein LDLRAP1Q136X affects the coding region of LDLRAP1, resulting in a glutamine amino acid being changed into a stop codon, truncating the protein at amino acid 136. Phylogenetic analysis of ten different animal species demonstrated that glutamine 136 is 100% conserved in the LDLRAP1 protein from the human protein to flies and frogs. An NCBI Conserved Domain Search for LDLRAP1 indicated that the LDLRAP1Q136X variant truncates the protein within a peptide binding domain, a phosphoinositol binding domain, as well as a domain that specifies the Pleckstrin protein superfamily of signaling proteins. IntFold 3D rendering of wild type (WT) and LDLRAP1Q136X proteins showed that the variant has a significant alteration in 3D structure, based on the loss of 172 amino acids. Further in silico analysis using amino acid interaction software showed that the LDLRAP1Q136X protein was missing its phosphotyrosine binding pocket. The rs121908325 mutation is rare, and none of the 70 genomes analyzed during a nutrition course at a large research I university carried this allele. These in silico studies demonstrate that the nonsense mutation at position glutamine 136 would impact specific domains of LDLRAP1, ultimately inhibiting the protein’s ability to perform its function of facilitating removal of the LDL receptor from cell surfaces, leading to increased circulating cholesterol levels and potential cardiovascular health complications. KEYWORDS: Cholesterol; Hypercholesterolemia; Low density lipoprotein; LDL; LDLR; LDLRAP1; Autosomal recessive hypercholesterolemia-4 (FHCL4); heart disease
p. 47. Investigation of a Photovoltaic Thermal-Direct Expansion Solar-Assisted Heat Pump (PVT-DXSAHP) Collector with Different Photovoltaic Characteristics in Cold Climates
Adam Anastas & Aggrey Mwesigye
https://doi.org/10.33697/ajur.2025.133
Abstract: In this paper, the performance of a direct expansion solar-assisted heat pump (DX-SAHP) with a photovoltaic thermal (PVT) collector made with different solar cells was investigated. A thermodynamic model of a direct expansion solar-assisted heat pump with a PVT collector and a 180 L water tank for thermal energy storage was developed. The model was implemented in MATLAB, with the CoolProp library for the retrieval of working fluid thermodynamic properties. The solar collector cells considered were ®Solartech, ®LG, ®Prime, ®VOLT, and ®VSUN. The performance of the system is characterized by the coefficient of performance, thermal efficiency, electrical efficiency, heat pump ratio and auxiliary heat ratio. The highest average coefficient of performance of the heat pump was with ®Solartech solar cells on a sunny day in winter was 4.08 , and 7.91 on a sunny summer day. On a cloudy summer day, the ®Prime solar cell had the highest average coefficient of performance at 6.45. The highest electrical efficiency of the collector was observed with ®Prime solar cells, with an efficiency of 14.4%, 16.5% and 13.6%, respectively, from a sunny day in winter, a sunny day in summer and a cloudy day in the summer. The highest thermal efficiency was obtained by ®Solartech solar cells for all weather conditions. With a collector area of 5 m2 and a consumer load of 0.001 kg/s, the heat pump meets an average of 15.6% of the total heat needed for domestic hot water demand on a sunny winter day. This increases to 38.2% and 49.0% on cloudy and sunny summer days, respectively. KEYWORDS: Coefficient of Performance; Direct Expansion; Heat Pump Ratio; Photovoltaic Thermal ; Water Heating; Solar-Assisted Heat Pump
p. 65. Ground-dwelling Invertebrate Community Composition Changes between Coastal Sage Scrub Community of San Diego and Tijuana with Urbanization
Anthony Ye & Kyle Haines
https://doi.org/10.33697/ajur.2025.134
ABSTRACT: Invertebrates are some of the most diverse and abundant groups of terrestrial organisms. They provide important functions within an ecosystem and can rapidly respond to environmental changes, such as urbanization, making them excellent ecological indicators for ecosystem function and health. Urbanization, and the disturbance and introduction of exotic plants often associated with it, affects invertebrate taxa, changing community composition, structure, diversity, and abundance of invertebrates. Some invertebrate taxa can exploit these changes and increase in abundance; while others exhibit sensitivity and are at risk of extirpation. The San Diego and Tijuana region has been increasing in urbanizing pressure for decades. Tijuana, in particular, has experienced exponential population growth over the past 30 years, and urbanization threatens the integrity of much of the remaining coastal sage scrub, an endangered and rare ecosystem unique to the coasts of southern California and northwestern Mexico composed of many coastal deciduous shrubs and annual wildflowers. However, the invertebrates currently residing in these semi-disturbed landscapes have rarely been sampled. In this study, ground-dwelling invertebrates from a native plant nursery in an urbanizing area of Tijuana at Vivero Hormiguitas and a protected site in Border Field State Park in San Diego were sampled to compare the changes in coastal sage scrub ground-dwelling invertebrate community composition in response to urbanization. Beetle abundance and richness decreased in the urbanizing site in Tijuana, while spider abundance and richness increased in Tijuana compared to the protected site in San Diego. Particularly, we noted decreases in Tenebrionidae abundance and failed to detect Silphidae, suggesting slower decomposition rates in the urbanizing Tijuana site. Although spider abundance in general increased, mostly due to increased prevalence of one genus, Xysticus, Gnaphosidae abundance decreased in the Tijuana site. Lastly, non-native invertebrate taxa, especially isopods, showed dramatic increases in abundance at the urbanizing Tijuana site, contributing to overall increases in invertebrate abundance in Tijuana compared to the protected site in San Diego. These results indicate that urbanization has negatively affected ecosystem functions in coastal sage scrub communities and that it has drastically impacted the diversity and health of this rare ecosystem, much of which is already fragmented, and actions need to be taken to protect this rare habitat as much of its range continues to become more urbanized. KEYWORDS: Beetle; Coastal Sage Scrub; Community Composition; Disturbance; Invasive Species; Invertebrates; San Diego; Tijuana; Spider; Urbanization
p. 85. Screen Time, Physical Activity, and Anxiety in Honors College Students during the COVID-19 Pandemic
Jack Parker, Karen C. Westervelt, Jeremy Sibold, & Susan Kasser
https://doi.org/10.33697/ajur.2025.135
ABSTRACT: Background: The COVID-19 pandemic presented a unique opportunity to study the effects of increased screen time on student mental health, as colleges and universities in the United States transitioned to virtual learning. Current literature suggests that college/university students, particularly those enrolled in Honors programs, are at an increased risk for symptoms of anxiety. Emerging research suggests that increased screen time increases anxiety but never had there been such a marked increase in screen time. Purpose: The aim of this pilot study was to observe the relationships between anxiety, screen time, and physical activity in Honors students during the COVID-19 pandemic. Methods: A REDCap survey, consisting of the GAD-7 measure of anxiety, screen time questionnaire, physical activity questionnaire, and self-reported impact of the pandemic, was distributed to Honors students. Results: Anxiety and screen time increased during the pandemic, while physical activity did not significantly change. Eighty-point-nine percent of respondents met GAD-7 scoring guidelines for mild to severe anxiety and 71.56% self-reported experiencing more anxiety than before the pandemic. Increased screen time was associated with increased GAD-7 score, independent of physical activity or COVID-19 impact. Increased physical activity was associated with decreased GAD-7 score. Conclusion: Anxiety and screen time increased in Honors students during COVID-19. Increases in screen time were associated with increased anxiety in Honors students, while physical activity was associated with decreased anxiety. Universities should consider strategies to mitigate negative effects of increased screen time, including the use of physical activity. KEYWORDS: COVID-19; Pandemic; Screen Time; Physical Activity; Anxiety; College Students; GAD-7; Technology; Media Effects; Children and Media