AJUR Volume 20 Issue 4 (March 2024)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 20 Issue 4 (March 2024) or https://doi.org/10.33697/ajur.2024.100

Links to individual manuscripts, abstracts, and keywords are provided below.


p.3. On Sample Size Needed for Block Bootstrap Confidence Intervals to Have Desired Coverage Rates

Mathew Chandy, Elizabeth D. Schifano, & Jun Yan

https://doi.org/10.33697/ajur.2024.101

ABSTRACT: Block bootstrap is widely used in constructing confidence intervals for parameters estimated from stationary time series. Theoretically, the method should provide valid confidence intervals as the length of the time series goes to infinity. In practice, however, it is necessary to know how large of a finite sample is required for block bootstrap confidence intervals to work well. This study aims to answer this question in a simple simulation setting where the data are generated from a first-order autoregressive process. The empirical coverage rates of several commonly used bootstrap confidence intervals for the mean, standard deviation, and the lag-1 autocorrelation coefficient are compared. A quite large sample is found necessary for the intervals to have the right coverage rates even when estimating a simple parameter like the mean. Some block bootstrap methods could fail when estimating the lag-1 autocorrelation. It is surprising that the coverage property even deteriorates as the sample size increases with some commonly used block bootstrap confidence intervals including the percentile intervals and bias-corrected intervals. KEYWORDS: Autocorrelation; Bias-Correction; Centering; Dependent Data; Percentile; Resampling; Simulation; Time Series

p.17. Faculty Opinions of AI Tools: Text Generators and Machine Translators

Mahlet Yitages & Akie Kasai

https://doi.org/10.33697/ajur.2024.102

ABSTRACT: Artificial Intelligence (AI) tools recently became a prominent concern in higher education classrooms. Many teachers have implemented the technology into their assignments, while others are strictly against this technology’s use for assignments. Either way, students have found ways to use it in their academic careers. Though research on the power of AI in the workplace exists, research is lacking in its appropriate use in higher education. Universities need to define AI’s role on campus and establish guidelines on how these tools may or may not be used and how faculty can recognize misuse, specifically related to academic integrity. This study aimed to determine how faculty view AI as a part of undergraduate literature, language, and linguistics programs. From the interview study, common themes emerged, including implementation, academic integrity, the human aspect of linguistics, and the future of AI writing tools. Interviewed faculty also stated that those in higher education must tread carefully through this strong intersection between technology and the arts to use AI responsibly, strategically, and ethically. KEYWORDS: Artificial Intelligence (AI); Artificial General Intelligence (AGI); Linguistics; Higher Education; ChatGPT; Machine Translation; Academic Integrity; Ethics

p.29. The Predicted Structure of a Thermophilic Malate Synthase

Shaelee Nielsen, Jantzen Orton, & Bruce R. Howard

https://doi.org/10.33697/ajur.2024.103

ABSTRACT: This project aims to solve the structure of the crenarchaeal Sulfolobus acidocaldarius enzyme malate synthase. Other known malate synthase enzymes have been found to require a magnesium ion in the active site to carry out catalytic activities, but a study reported that S. acidocaldarius malate synthase does not require magnesium. This suggests a novel mechanism for this enzyme. Additionally, the mature S. acidocaldarius protein is approximately 100 residues larger than any other structurally characterized malate synthase. It has also been reported to form a dimer, while previously solved structures have only displayed monomeric, trimeric, and hexameric arrangements. We plan to determine the structure experimentally.  However, major advances in the accuracy of protein structure prediction were made recently by AlphaFold, an artificial intelligence system developed by DeepMind, which has revolutionized the field and has largely solved the protein folding problem. A similar AI system, RoseTTAFold, developed by David Baker’s lab at the University of Washington, has been publicly available. Here, we report our analysis of the structure of this protein, predicted using both of these algorithms and of a predicted structural model for the dimeric form of the enzyme using ClusPro. Our results strongly support a conserved catalytic mechanism requiring magnesium, which is common with all previously solved malate synthase isoforms. KEYWORDS: Glyoxylate Cycle; Malate synthase; Protein Prediction; Thermophile; Sulfolobus acidocaldarius; Magnesium; AlphaFold; RoseTTAFold

p.39. The Impact of Narratives on Healthcare Decision-Making in Online Discourse

Zayd Almaya & Tom Mould

https://doi.org/10.33697/ajur.2024.104

ABSTRACT: This study examines first what type of evidence is most influential in online discussions for patients when making decisions about their health and second how people deploy, interpret, and react to stories in these online discussions to better understand the role and importance of narrative in the medical field. Data was gathered on the platform Reddit using the subreddit r/melanoma for a duration of two weeks. 242 posts were collected and analyzed. Using a combination of grounded theory and coding criteria from sociologist and narrative scholar Francesca Polletta, a code book was developed and applied to all 242 posts to assess narrative impact and engagement. Results demonstrate that evidence based on past experiences and factual information were the most persuasive. Additionally, stories yielded greater discussion, greater empathetic connections, and greater positive responses from online discussants than other forms of evidence. Further, those positive responses indicate that patients seeking medical advice were more likely to express agreement with the advice when it was offered with a story. Given these results, greater attention should be paid to narratives shared in online communities, particularly considering the levels of misinformation and disinformation found online and the evolving relationships between doctors and patients where authority is no longer so easily assumed. KEYWORDS: Narrative; Personal Experience; Fact; Evidence; Persuasion; Medical Decision-Making; Social Media

p.53. Elongation Factor P is Required for Processes Associated with Acinetobacter Pathogenesis

Dylan Kostrevski & Anne Witzky

https://doi.org/10.33697/ajur.2024.105

ABSTRACT: Antibiotic resistance is one of the world’s fastest-growing and most prevalent problems today. The influx of antibiotics within our environment from inadequate antibiotic stewardship has led to a surge of drug-resistant microorganisms. The CDC has classified Carbapenem-resistant Acinetobacter (CRA) as an urgent threat within this crisis. New drug development is imperative to combat infections caused by drug-resistant pathogens such as CRA. Bacterial translation, the process of protein synthesis by the ribosome, is a common target for new antibiotic development. Elongation factor P (EF-P) is a universally conserved translation factor required for antibiotic resistance in many bacteria. In this study, we assessed the importance of EF-P in processes associated with Acinetobacter pathogenesis. In the absence of EF-P, Acinetobacter baylyi displays decreased biofilm formation, surface-associated motility, and resistance to beta-lactams and carbapenems. This data holds hope for future drug development targeting EF-P in pathogens closely related to A. baylyi. KEYWORDS: Acinetobacter baylyi; Translation; Ribosome; Elongation Factor P; Polyproline; Biofilm; Surface Associated Motility; Antibiotic Resistance

p.63. Measurement System for Compliance in Tubular Structures

Ave Kludze, Anthony R. D’Amato, & Yadong Wang

https://doi.org/10.33697/ajur.2024.106

ABSTRACT: Tubular structures such as blood vessels, intestines, and the trachea are common in various life forms. This paper describes a measurement system to test the mechanical compliance of tubular structures. The novelty of the system lies in its hardware and software. Here we use vascular graft as an example to demonstrate the utility of the system. A fully synthetic vascular graft would ideally mimic the mechanical and architectural properties of a native blood vessel. Therefore, mechanical testing of the graft material under physiological pressure is crucial to characterizing its potential in vivo performance. The device operates through a low-cost Arduino-based control system that simulates and measures cyclic fluid pressure changes over time and a laser micrometer that measures diameter changes with pressure. This system is low-cost, assuming one already has access to a laser micrometer. In contrast to previous methods, this system offers a simple, low-cost, and customizable option to measure compliance and is equipped with data acquisition/analysis programs. These programs include a MATLAB application that processes and synchronizes Arduino Uno pressure signals and LabChart Pro diameter readings. Lastly, this paper explains the hardware and software of the measurement system. The system is beneficial for testing the pressure-diameter relationship of tubular structures of varying sizes and materials. KEYWORDS: Tubular Structures; Compliance; Data Acquisition System; Physiological Pressure; Diameter Change; Arduino Uno; LabChart Pro; MATLAB

p.77. Fibroblast Embedded 3D Collagen as a Potential Tool for Epithelial Wound Repair

Claire Behning, Lia Kelly, Emma Smith, Yizhe Ma, & Louis Roberts

https://doi.org/10.33697/ajur.2023.107

ABSTRACT: Collagen is a functional biomaterial with many applications, including wound healing. 3D collagen hydrogels mimic an in vivo cell culture experience used in cell survival and growth studies. In experimentally examining human cells under contact with 3D collagen, it is possible to understand the role of collagen in human epithelial tissue repair. This study explored the growth and attachment response of human MCF-7 cells when exposed to 3D collagen by investigating if the presence of NIH/3T3 fibroblasts embedded within the collagen should produce an increased wound-healing response. 3D collagen and fibroblast presence were able to be analyzed in tandem with a “sandwich-like” configuration of the gels to determine how these variables impact or improve the tissue repair response in MCF-7 cells. Examinations in growth, attachment, viability, and migration patterns demonstrated that MCF-7 repair response may be increased when in contact with NIH/3T3 embedded 3D collagen without impairing viability. Most notably, results from the migration assay revealed that MCF-7 cells migrate the most when covered by and adhered to cellular 3D collagen. Fibroblast-embedded collagen on top of and below MCF-7 cells exceeded quantitative assessment to near confluency, whereas less than 50 counted cells per image migrated without any top collagen layering. The continuation of these methods could involve in vivo experiments that incorporate live animal models to determine if these results will continue to extend to live tissue. KEYWORDS: Collagen; 3D Collagen; Fibroblasts; Wound Healing; Hydrogels; Tissue Repair; Migration

AJUR Volume 20 Issue 3 (December 2023)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 20 Issue 3 (December 2023) or https://doi.org/10.33697/ajur.2023.091

Links to individual manuscripts, abstracts, and keywords are provided below.


p.3. Walking After Dark: A Sidewalk Illumination Case Study in Cedar City, UT

Sabrina Waite, Ian Nelson, & Jamie Spinney

https://doi.org/10.33697/ajur.2023.092

ABSTRACT: Sidewalks are an important part of public space, but they are becoming increasingly dangerous, especially at night. Therefore, it is important that sidewalks are adequately illuminated to meet the safety, comfort, and accessibility needs (i.e., provide high levels of pedestrian reassurance) to sidewalk users. The objective of this case study was to quantitatively measure and subsequently explore the spatial and statistical distributions of light intensities along the sidewalks that surround Southern Utah University in Cedar City, Utah. A secondary objective was to develop a set of “adequate lighting” guidelines (i.e., 5 to 10 lux) to help identify areas that could benefit from sidewalks lighting enhancements. A digital light meter was used to measure horizontal light intensity, in lux, at a systematic sample of 208 points along the sidewalks within the study area. Geographic coordinates were also collected for each sample observation to enable mapping and spatial analysis of the light intensity data. Results indicate 61% of the observations have lux values equal to zero (complete darkness), 13.4% met or exceeded the minimum guidelines, while 4.3% fell within the “adequate lighting” guidelines adopted by this case study. These results suggest that sidewalks are too dark in too many places to provide reassurance to sidewalk users in the study area. The mapping and spatial analysis results from this case study also provide information to support targeted visibility enhancements of sidewalks within the study area. KEY WORDS: Lighting; Optimum Illuminance; Luminometer; Sidewalks; Pedestrians; Safety; Security; Reassurance

p.13. Effect of Retinoic Acid on HaCaT and NIH-3T3 cells in an in vitro 3D Collagen Cell Culture Skin Model

Olivia Atkins, Samantha Lopez, Yizhe Ma,& Louis Roberts

https://doi.org/10.33697/ajur.023.093

ABSTRACT: Human skin aging is characterized by epidermal and dermal thinning, loss of elasticity, and wrinkles. Keratinocytes, the most common type of skin cell and fibroblasts, present in the cellular stroma beneath the skin’s surface, each play a role in aging. Using these cell types in in vitro research can reveal a deeper understanding of the dermatological function and cellular changes in aged skin. 3D cell culture techniques provide an opportunity to use these cell types in a model that can more accurately mimic human skin. Treatment of aging skin is of interest to both medical and consumer communities. Retinoic acid (RA) is a metabolite of vitamin A and retinol that assists in cell proliferation, differentiation, and immune functions. Over the counter (OTC) and prescription retinoids are common topical products used for anti-aging and acne treatments. This study seeks to determine the impact of topical retinoid creams on keratinocyte proliferation and morphology in 3D cell culture models of aged and unaged human skin. NIH-3T3 fibroblasts were embedded in a 3D collagen matrix of varying thickness, and HaCaT keratinocytes were seeded on top of the matrix at varying seeding densities to mimic aging and youthful skin. 0.1 µM 0.025% tretinoin and 0.1 µM 0.1% adapalene topical creams were prepared in culture medium and used to treat cells daily, on alternate days, or just once during a week-long period. AlamarBlue assays and microscopy showed that tretinoin treatment was cytotoxic at this concentration, with a single treatment reducing cell viability by ~43% compared to the untreated control. Adapalene treatment, while showing significantly greater cell proliferation than tretinoin, did not exceed the proliferation of the untreated control. It is understood that retinol increases cell turnover by killing cells rapidly, so it is proposed that in our model, the rate of proliferation does not overcome the rate of cell death. Cell viability trends remain similar between young and old skin model treatments. Future studies should focus on creating a 3D model more accurately representing the aging in vivo skin environment where keratinocytes can be readily differentiated from epidermal stem cells. KEYWORDS: HaCaTs; NIH-3T3; Retinoids; Retinoic Acid; Tretinoin; Adapalene; 3D Collagen Gel; Proliferation

ajur.2023.093_appendix

p.25. Increasing Access to a Four–Year College: Impacts of a California State University Guaranteed Admission Program on College Enrollment Rates

Joleen Chiu

https://doi.org/10.33697/ajur.2023.094

ABSTRACT: Guaranteed admission programs are a type of college access program that provide students who meet certain criteria (e.g., a minimum GPA) with guaranteed admission to one or more colleges. This paper studies guaranteed admission agreements between California State University San Marcos (CSUSM) and its local school district to evaluate if smaller scale, local guaranteed admission programs have comparable impacts on college enrollment rates to previously studied state-wide programs. Employing a regression discontinuity (RD) design around the program’s GPA cutoff conditional on students satisfying other program requirements, this paper finds that the program significantly increased enrollment at CSUSM and at any California State University (CSU) and increased (not significantly) the likelihood of students enrolling at four-year institutions compared to two-year alternatives. In addition, the program disproportionally affected students from underrepresented backgrounds (e.g., first-generation, nonwhite, and low-income backgrounds), suggesting that local guaranteed admission programs also have the potential to increase representation at four-year public institutions and encourage underrepresented students to enroll at higher-quality postsecondary institutions. KEYWORDS: Guaranteed Admission; College Enrollment; College Admissions; College Access; Higher Education; California State University; Education Policy; Local Policy

ajur.2023.094_appendixes

p.51. Conflicting Socio-Cultural Attitudes and Community Factors Resulting in Backstreet Abortion in Cato Manor, KwaZulu-Natal

Chloe M. Sachs

https://doi.org/10.33697/ajur.2023.095

ABSTRACT: Abortion in South Africa is a complex topic, rife with augmenting and limiting political, social, religious, and cultural factors. This study explores multiple age groups within Cato Manor and whether the attitudes towards abortion and factors impacting the choice of where and whether to receive an abortion differ. The study employs a general qualitative approach with inserted narratives highlighting individual perspectives and stories. The sample cohort was identified using purposive sampling of women, obtained via convenience through the gatekeeper in the community. The participants are from two generations, and two expert interviews were conducted to gain various perspectives. The sample population is from the greater Cato Manor community, and the interviews were conducted in a semi-structured format. The main goal of this study is to understand how socio-cultural factors impact abortion attitudes within each generation in Cato Manor and if community attitudes impact women’s decisions on how and where to obtain medical abortions. The findings show that negative attitudes towards abortion persist in Cato Manor due to religious and cultural rationale. Greater acceptance occurs among younger generations following abortion legalization in South Africa, yet prejudice remains. The research reveals a range of factors that may pressure women to obtain illegal abortion options to avoid community shame. KEYWORDS: Abortion; Pregnancy Termination; South Africa; KwaZulu-Natal; Cato Manor; Backstreet Abortions; Abortion Attitudes; Illegal Abortion

ajur.2023.095_appendix

p.69. Dynamic Structural Equation Models: Promising Yet Concerning

Suryadyuti Baral & Patrick J. Curran

https://doi.org/10.33697/ajur.2023.096

ABSTRACT: Dynamic Structural Equation Model (DSEM) is a powerful statistical modeling approach that has recently gained popularity among researchers studying intensive longitudinal data. Despite its exciting potential, the stability and replicability of DSEM is yet to be closely examined. This study empirically investigates DSEM using recently published data to explore its strengths and potential limitations. The results show that while some of its parameter estimates are stable, others are characterized by substantial variation as a function of seemingly innocuous initial model estimation conditions. Indeed, some parameters fluctuate between significance and non-significance for the same model estimated using the same data. The instability of DSEM estimates poses a serious threat to the internal and external validity of conclusions drawn from its analyses, challenging the reproducibility of findings from applied research. Given the recent focus on the replication crisis in psychology, it is critical to address these issues as the popularity of DSEM in psychological research continues to rise. Several potential solutions are investigated to address this problem and recommendations of best practice are offered to applied researchers who plan to use DSEM in intensive longitudinal data analysis. KEYWORDS: Dynamic Structural Equation Model; Bayesian; Robust Estimation; Intensive Longitudinal Data

p.81. Finding the Fixing Number of Johnson Graphs J(n, k) for k Є {2; 3}

James Della-Giustina

https://doi.org/10.33697/ajur.2023.097

ABSTRACT: The graph invariant, aptly named the fixing number, is the smallest number of vertices that, when fixed, eliminate all non-trivial automorphisms (or symmetries) of a graph. Although many graphs have established fixing numbers, Johnson graphs, a family of graphs related to the graph isomorphism problem, have only partially classified fixing numbers. By examining specific orbit sizes of the automorphism group of Johnson graphs and classifying the subsequent remaining subgroups of the automorphism group after iteratively fixing vertices, we provide exact minimal sequences of fixed vertices, in turn establishing the fixing number of infinitely many Johnson graphs. KEYWORDS: Graph Automorphism Groups; Symmetry Breaking; Fixing Number; Determining Number; Johnson Graphs; Kneser Graphs; Graph Invariants; Permutation Groups; Minimal Sized Bases.

p.91. Anxiety as a Predictor of Movement During a Math Task in Elementary School Children

Gabriella Snetkov, Anna E. Youngkin, Megan E. Lui, Analia Marzoratti, &Tanya M. Evans

https://doi.org/10.33697/ajur.2023.098

ABSTRACT: Anxiety can come in various forms; general anxiety is characterized by feelings of excessive anxiety impacting multiple domains of everyday life, whereas anxiety may also manifest within a single domain (i.e., math anxiety). Those that present with anxiety who also have Autism Spectrum Disorder often exhibit ritualized movement as a coping mechanism for their anxiety. However, the relationship between anxiety and movement has not yet been explored within typically developing children. It is also unclear if the form of anxiety impacts the degree to which children move. In this study, we used Motion Energy Analysis to quantify the relationship between both general and math anxiety and movement during a math flashcards task. Multivariate linear regression analysis was used to determine possible relationships between anxiety and movement. General anxiety significantly contributed to models predicting movement during the math flashcards task, while math anxiety did not. Our results suggest that movement could be an indicator of general anxiety in elementary aged children. KEYWORDS: General Anxiety; Math Anxiety; Elementary; Academics; Motion Energy Analysis; Movement; Ritualized Movement; Mathematics

ajur.2023.098_appendix

p.99. Chitosan-Silver Thin Film-Coated Titanium Coupons using Silane Linkers Inhibit Biofilm and Planktonic Growth

Emily C. Montgomery, Nidhi Gupta, Matthew Atwill, Joel D. Bumgardner, & J. Amber Jennings

https://doi.org/10.33697/ajur.2023.099

ABSTRACT: Titanium is a component of many implants and orthopedic instruments, such as screws and rods; however, this and other materials may serve as a nidus for bacterial biofilm attachment. Chitosan is a biopolymer with advantages as a surface modifier, and silver ions have broad-spectrum antimicrobial properties. For this study, chitosan is bound to silver through a novel, patented process. The purpose of this research is to characterize silane-linked chitosan-silver coatings for titanium, including comparing antimicrobial efficacy. In this study, silane-linked chitosan-silver titanium coupons reduced Staphylococcus aureus (S. aureus) viability by 98% (planktonic) and 99.5% (biofilm) while supporting viability of Saos-2 osteoblast cells at levels of 75% compared with control uncoated titanium. Due to the observation of retaining osteoblast viability while reducing bacterial viability, silane-linked chitosan-silver coatings could be useful for titanium implants to reduce post-operative infection as well as support the healing process.

KEYWORDS: Titanium; Staphylococcus aureus; Silver; Chitosan; Silane; Osteoblast; Antimicrobial; Coating

AJUR Volume 20 Issue 2 (September 2023)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 20 Issue 2 (September 2023) or https://doi.org/10.33697/ajur.2023.082

Links to individual manuscripts, abstracts, and keywords are provided below.


p.3. An Exploratory Study on Student-Athlete Mental Health: Personal and Perceived Barriers to Help-Seeking Behavior

Emma McCabe, Sarah DeSordi, Aaron Piepmeier, & Eric Hall

https://doi.org/10.33697/ajur.2023.083

ABSTRACT: Student-athletes are more likely to develop mental health problems than the general population. In addition to schoolwork, social networks, family ties, and financial obligations, collegiate student-athletes are required to attend practices, travel for games, attend athletic events, and perform extracurricular duties. The addition of possible injury, overtraining, burnout, scrutiny from the public and/or the media, and consistent pressure to perform results in athletes playing through both physical injuries and mental health problems. Despite the high number of athletes who report needing mental health support, fewer than half seek out mental health services. Research has identified stigma as one of the largest barriers to mental health help-seeking behavior (HSB). Help-seeking behavior has rarely been studied in relation to the larger body of work on mental health stigma in sport. The purpose of this study was to observe and describe student-athletes’ perceived stigma (e.g., what others think) and personal stigma (e.g., what the individual thinks) in relation to HSB. A sample of n = 20 athletes completed an online Qualtrics Survey, which included Link’s Perceived Discrimination and Devaluation Scale, Mental Health Literacy Scale, Self-Stigma of Seeking Help Scale, Help Seeking Questionnaire, and Student-Athlete Role Behaviors Questionnaire. Results from this study may help develop mental health interventions to improve student-athlete HSB. KEYWORDS: Mental Health; Student-Athlete; Stigma; Help-Seeking Behavior; NCAA; PDDS; MHLS; SSOSH; HSQ; SRBQ

p.13. The Effect of Coastline Concavity on Maximum Storm Surge Height along the US Gulf Coast

Kayleigh Addington & Stephanie Zick

https://doi.org/10.33697/ajur.2023.084

ABSTRACT: Storm surge is the most dangerous component of landfalling tropical cyclones (TCs). The growing coastal population highlights the importance of research regarding the atmospheric and geographic factors influencing the maximum storm surge height (MSSH). To date, few studies have investigated the influence of coastline concavity. Here, we investigate the hypothesis that TCs making landfall on a concave coastline will have a higher MSSH than TCs making landfall on a convex coastline. The Colorado State University extended best track dataset includes the radius of 34 kt winds (R34), landfall minimum mean sea level pressure (MSLP), landfall maximum sustained winds, and forward speed of TCs. The storm surge database for the US Gulf Coast provides the location and MSSH for TCs impacting the U.S. Gulf Coast. From this, eleven TCs that meet specific criteria and represent the larger population of Atlantic TCs are selected. The adjusted degree of coastline concavity (ADoC) is calculated for each TC using the law of cosines and 50, 100, and 200 km radius buffers around the point of MSSH. A Mann Whitney U test does not indicate any significant differences between the mean MSSH of TCs making landfall on each coastline type. Additionally, results from a simple linear regression F-test suggest that none of the included parameters have a significant influence on MSSH despite the findings of previous research. Still, the Spearman’s Rho correlation values suggest a weak positive relationship between the ADoC and MSSH. This relationship is significant at the 100 and 200 km buffers, which is consistent with the hypothesis. Results are limited by the small sample size. Future research should use a larger dataset and investigate how each individual storm characteristic affects MSSH. KEYWORDS: Tropical Cyclones; Hurricanes; Storm Surge; Coastal Geography; Coastline Concavity; Gulf of Mexico; Law of Cosines

p.29. Validation of a Computationally Efficient Model of the Mu-Opioid Receptor

Allison Barkdull, Lexin Chen, Akash Mathavan, Karina Martinez-Mayorga, & Coray M. Colina

https://doi.org/10.33697/ajur.2023.085

ABSTRACT: The mu-opioid receptor (MOR) is a transmembrane protein and the primary target for pain-modulating drugs. Opioid drugs come with detrimental side-effects such as physical dependence and addiction. However, recent studies show that understanding structural properties and dynamics of MOR may aid in the design of opioid drugs with reduced side-effects. Molecular dynamics simulations allow researchers to study changes in protein conformation at an atomistic level. However, modeling systems including MOR embedded in a lipid bilayer can be computationally expensive. This study evaluates a modeling approach that uses harmonic restraints on the transmembrane regions of MOR to model the rigidity of the lipid bilayer without explicitly simulating lipid molecules, reducing the number of atoms in the simulation. The proposed model allows MOR to be simulated 49% faster than a simulation explicitly including the lipid bilayer. To assess the accuracy of the proposed model, simulations were performed of MOR in a lipid bilayer, the free MOR in water and MOR in water with harmonic restraints applied to all transmembrane residues using NAMD 3.0 alpha and the CHARMM36 force field. Dynamic properties of MOR were shown to be different in each system, with the free MOR having a higher root mean square deviation (RMSD) than MOR with an explicitly modeled lipid bilayer. The systems with harmonic restraint constants of 0.001 kcal/mol/Å2 applied to the transmembrane residues had RMSD values comparable to those in an explicitly modeled lipid bilayer. This study demonstrates that using restraints on the transmembrane residues of MOR is a feasible way of modeling the ligand-free receptor with reduced computational costs. This model could allow the dynamics of MOR in a lipid bilayer environment to be studied more efficiently. KEYWORDS: Molecular Dynamics; Atomistic Simulations; Computational Modeling; Mu-Opioid Receptor; G-Protein Coupled Receptor; Lipid Bilayer, Opioid, Transmembrane Protein

p.45. A Review of Models on Direct Evaporative Cooling

Michael Wilkins & Nelson Fumo

https://doi.org/10.33697/ajur.2023.086

ABSTRACT: Direct evaporative cooling (DEC) is a technology that is continuously expanding into different areas of study. The foundation of this process has been built through expansive research efforts and physical experimental data. The ability to accurately model and predict the performance of DEC systems allows the energy-efficient process to gain traction in HVAC applications, however, the inconsistencies present among research efforts created discontinuities in the reproduction of a system. By reviewing current literature, the discrepancies in the defining methodologies of how DEC systems are defined and predicted can provide insight to future research. This review depicts the different approaches taken in recent research to define the equations that govern the thermodynamic processes, the different materials used in the process, and the models used to predict the performance of DEC systems. By identifying the most common practices in current research, the gaps in literature can be recognized and overcome in further efforts. KEYWORDS: Direct Evaporative Cooling; Evaporative Cooler; Evaporative Cooling Media; HVAC; Cooling Effectiveness

p.57. Semantic Interpretations of Ditransitive Constructions in English

Marcella Jurotich

https://doi.org/10.33697/ajur.2023.087

ABSTRACT: This study addresses claims made by two theories—the Alternative Projection and Verb Sensitive approaches—regarding an interpretation of possession attributed to certain ditransitive constructions. The Alternative Projection approach argues that an interpretation of possession is only available in the double object (DO) pattern expressed by English ditransitive verbs (1a) and is not available in the prepositional (PP) pattern (1b). The Verb Sensitive approach argues that this possession interpretation is either available for both the DO and PP patterns, or for neither pattern, depending on the class of ditransitive verb with which the patterns occur. (1a) The salesperson gave the young farmer the grain mixture. (1b) The salesperson gave the grain mixture to the young farmer. Both approaches posit a possession interpretation of the DO pattern across all ditransitive verbs. This study tests to what degree native English speakers interpret a meaning of possession from the DO and PP patterns through an online survey with 88 participants. Ditransitive verbs from five semantic classes are analyzed to determine if the interpretation of possession varies based on use of the DO or PP pattern (Alternative Projection) or by the semantic class of the verb (Verb Sensitive). The results do not support the Alternative Projection approach. The results suggest partial support for the Verb Sensitive approach, as semantic classes do not entirely follow the pattern predicted by this approach.  Further, judgements reported in this study contradict some judgements reported in the literature, highlighting the importance of quantitative studies in evaluating theoretical claims. KEYWORDS: Ditransitives in English; Ditransitive Verbs; Survey; the Dative Alternation; Semantics; Verb Semantics; Alternative Projection approach; Verb Sensitive approach

p.69. Are Wrist-based Heart Rate Monitors a Valid Tool for Fitness Professionals to Measure Training Intensity During Exercise Classes?

Korey Little, John C. Sieverdes, D. David Thomas, M. Blake Lineberger, Daniel B. Bornsteind, Marco Bergamine, & Wesley D. Dudgeon

https://doi.org/10.33697/ajur.2023.088

ABSTRACT: This article aims to inform personal trainers and group fitness coaches about the validity and utility of wrist-located heart rate (HR) monitors compared to chest-located HR monitors for training purposes. HR from four wrist-based optical sensor HR products (Fitbit Charge HR, Garmin Vivosmart HR, Apple Watch series 1, Mio Fuse) were compared against a Polar H7 chest strap & RS800cx receiver during nine activities. Two researchers visually observed HR during a protocol incorporating resting, standing, a grocery bag carry, and a 6-stage cycle ergometer protocol that reached maximal HR. Pearson’s r and interclass correlations (ICC) in the sample (n=45, mean age=20.22 [SD 2.32]) resulted in the following: Mio Fuse r=.93, ICC=.97; Apple Watch 1 r=.91, ICC=.95; Fitbit Charge HR r=.83, ICC=.91; and Garmin Vivosmart HR r=.74, ICC=.85 (all p’s <.001). Bland-Altman plots showed the lowest bias for the Mio (-3.30 bpm), followed by the Apple Watch (-2.82 (SD:14.6) bpm), Garmin (-2.99 (SD:23.9) bpm) with Fitbit having the highest bias (-8.13 (SD:20.6) bpm). No drift in bias was found for any device in successive HR categories (all p’s >.09). Wrist-based HR monitors were deemed acceptable for fitness classes, though caution should be taken when interpreting any singular visually observed measurement point. KEYWORDS: Smartwatch; Heart Rate Monitoring; Fitness; Fitness Watch; Validity; Exercise; Cycle Ergometer; Training; Intensity

p.79. Retributive Attitudes and Perceptions of Police Use of Excessive Force

Amelia Collins, Sherah L. Basham, & Rick Dierenfeldt

https://doi.org/10.33697/ajur.2023.089

ABSTRACT: Public opinions of police use of force vary widely. Previous studies, however, have framed their examinations around the factors that influence support of police use of force in general, as compared to a focus on excessive force. This study utilized linear regression to examine the relationship between perceptions of police use of excessive force and retributive attitudes. The study employed a sample of 5,527 respondents from the American National Election Studies (ANES) 2020 Time Series Survey. Findings indicated that respondents’ perceptions of the frequency of police use of excessive force depend on their retributive attitudes. The more retributive one’s attitude, the less often they perceived the police to use too much force. Similarly, the more conservative one’s political ideology, the less frequently they perceived police used excessive force. Perceptions of police excessive force also vary across demographics. KEYWORDS: Retributiveness; Death Penalty; Police Use of Force; Police Excessive Force

p.87. College Canines: Investigating the Behavioral and Physiological Impacts of Various College-Housing Environments on Companion Dogs

Kaitlyn Willgohs, Jenna Williams, Isabella Crisostomo, Katherine Keck, Crystal Young-Erdos, & Lauren Highfill

https://doi.org/10.33697/ajur.2023.090

ABSTRACT: Companion animals are becoming a more familiar sight on college campuses, and they are often viewed as an essential element of wellness by students and institutions of higher education. While previous studies have investigated the behavioral and physiological impacts of bringing a pet to campus on the owners, impacts on the pets themselves have yet to be explored. Previous studies do suggest, however, that when dogs are left alone, they display more anxiety-related behaviors such as barking, destruction, lip-licking, body shaking, and higher levels of alertness. The present study investigated the difference in anxiety-related behaviors between on-campus dwelling dogs (n = 18) and off-campus dwelling dogs (n = 12) when exposed to a novel environment, and the physiological baseline of the dogs. Specifically, a saliva sample was collected from each dog before they were placed into a novel room for three minutes and their behavior was coded. Overall, there were no significant differences found between the two groups in either the anxiety-related behaviors observed or salivary cortisol levels. The implications of our findings for campus dogs will be discussed. KEYWORDS: Companion Animals; Dogs; Behavior; Cortisol; Higher Education; Dog Welfare; Service Animals; Animal-Assisted Interventions; Student Mental Health

AJUR Volume 20 Issue 1 (June 2023)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 20 Issue 1 (June 2023) or https://doi.org/10.33697/ajur.2023.075

Links to individual manuscripts, abstracts, and keywords are provided below.


p.3. Divestment Movements over Environmental Issues: The Brazilian Amazon Case

Pedro Eymael

https://doi.org/10.33697/ajur.2023.076

ABSTRACT: Devastating forest fires in Brazil’s Amazon rainforest, one of the most important biomes for Earth’s climate balance, have captured the world’s attention in 2019 and 2020. Foreign governments, non-governmental organizations, and institutional investors pressured Brazilian President Jair Bolsonaro to act and control the situation. Within this context, institutional investors threatened to divest from companies potentially linked to the wildfires and to sell government bonds, creating a divestment movement. Against this background, this article shows that Bolsonaro’s responses varied for each of the groups criticizing the handling of the environmental situation. It is argued that the Brazilian government adopted a more conciliatory tone and took more concrete actions when responding to institutional investors’ demands, compared to the responses for foreign governments and non-governmental organizations (NGOs). Based on fifteen in-depth interviews conducted in 2021 with professionals involved in this divestment case, the paper concludes that institutional investors played a key role in Bolsonaro’s winning coalition and electoral aspirations. Moreover, the shortage of financial capital due to the COVID-19 pandemic created further incentives for Bolsonaro to avoid conflicts with institutional investors. KEYWORDS: Divestment; Amazon Rainforest; Wildfires; Investors; Climate Change; Brazil; Politics

p.27. Using Coral Color to Indicate Coral Health in Five Caribbean Species

Gabriella Herrera, Alexandra M. Good, Alexander Hirota, Catherine Razal, Nicole Gaertner, Justin Sefcik, Jesse Gilbert, & Keisha D. Bahr

https://doi.org/10.33697/ajur.2023.077

ABSTRACT: Coral reefs are one of the most biodiverse and productive ecosystems on Earth, and color has been shown to indicate coral health in Australian and Hawaiian reef systems. However, no standardized method exists to quantify coral health for Caribbean corals. Therefore, a health assessment card using coral color was developed for five species of Caribbean corals to monitor coral health non-invasively. To quantify coral health, individual corals of each species were photographed in a controlled environment to develop color profiles. Simultaneously, nondestructive measurements of “health” were quantified by measuring photosynthetic efficiency (Fv/Fm) using pulse amplitude modulation (PAM) fluorometry, which determines how efficiently the symbiotic algae provides energy to the coral host. The results of this work successfully corresponded photosynthetic efficiency to coral color for five dominant species of Caribbean corals to develop a Coral Health Assessment Card for Caribbean reefs. Implementing a standardized assessment of symbiont performance can assist in monitoring changes in coral health, which can consequently be implemented into long-term and widespread monitoring projects to track overall Caribbean reef health.
KEYWORDS: Photosynthetic Efficiency, Symbiodinium spp., Coral Bleaching, Pulse-amplitude Modulated Fluorometry, Health Assessment

p.37. Synthesis and Palladium-Catalyzed Cross-Coupling of an Alkyl-Substituted Alkenylboronic Acid Pinacol Ester with Aryl Bromides

Shoma Mukai & Nathan S. Werner

https://doi.org/10.33697/ajur.2023.078

ABSTRACT: The palladium-catalyzed cross-coupling reaction of alkyl-substituted alkenylboron reagents with aryl halides is a versatile method to introduce a hydrophobic hydrocarbon chain onto organic compounds of interest. The application of the cross-coupling reaction is enabled by synthetic methods for the preparation of alkenylboron reagents. The geometrically pure, alkyl-substituted alkenylboron reagent, (E)-octenylboronic acid pinacol ester, was prepared by 9-BBN-catalyzed hydroboration reaction of 1-octene with pinacolborane in refluxing 1 M THF solution. This reagent was then evaluated in palladium-catalyzed cross-coupling reactions with aryl bromides. The highest yield of the (E)-1-phenyloctene was obtained when SPhos was used as the ligand, K2CO3 was used as the base, and DMF was used as the reaction solvent. Other electron-rich, electron-poor, sterically hindered, and heteroaromatic substrates produced the corresponding (E)-1-phenyloctene derivatives in moderate to good yield.
KEYWORDS: Organic synthesis; Aryl alkene synthesis; Palladium-catalyzed cross-coupling; Suzuki-Miyaura reaction; Stereocontrolled alkene preparation; Hydroboration; 9-Borobicyclo[3.3.1]nonane; Reaction optimization

p.47. Spawning Conditions Affect Clutch Probability and Size in Laboratory-Housed Zebrafish (Danio rerio)

Sydni Anderson, Elizabeth Sipes, Megan Franke, & Dena R. Hammond-Weinberger

https://doi.org/10.33697/ajur.2023.079

ABSTRACT: Zebrafish are common experimental models used in biological studies that are bred and raised in laboratory settings. Published studies, anecdotal evidence, and industry practices are variable and offer conflicting suggestions on maximizing reproductive success, particularly regarding sex ratios and segregating males and females before spawning. This study identified conditions that promote maximum reproductive success (clutch probability and average clutch size) in zebrafish. Clutch probability was higher when females were seven to ten months old and bred in groups with equal sex ratios and an artificial spawning substrate in the winter or spring. Clutch size was significantly larger when females were seven to ten months old, outnumbered by males, and bred with an artificial spawning substrate. Optional spawning substrates (marbles and plants) improved reproductive success, whereas other parameters had no impact. These data support the implementation of simple steps that reliably maximize reproductive success of laboratory zebrafish.
KEYWORDS: Reproduction; Breeding; Seasonality; Behavior; Substrate; Sex Ratios; Captivity; Eggs

p.59. Color Saturation: Upper and Lower Percentage Histogram Manipulation

Kyra Obert , Maria Schudt , & Ian Bentley

https://doi.org/10.33697/ajur.2023.080

ABSTRACT: There are various color correction techniques that can be applied to digital photographs to account for environmental lighting variations. This manuscript contains a proposed method for such color correction. The method involves saturating an image by a specified percentage of its pixels via upper and lower percentage histogram manipulation using the image’s RGB histograms. Variations of this new technique, the white balance (WB) correction method, and a multivariable fit are used to test its performance against common color correction techniques. The findings demonstrate that the upper and lower percentage histogram manipulation method is not only more applicable to photos because it doesn’t require calibration regions to be sampled but it is also more consistent in its correction of photos when there are substantial gray scale features (e.g. a black and white grid or text). Our motivation for testing these techniques is to find the most robust color correction technique that is broadly applicable (not requiring a color checker chart) and is consistent across different lighting.
KEYWORDS: Color Correction; Histogram Manipulation; Saturation; White Balance; Scientific Image Analysis; Color Comparisons; Euclidean Distance; Standard Deviation; Color Difference

p.77. Overexpression of MMACHC Prevents Craniofacial Phenotypes Caused by Knockdown of znf143b

Isaiah Perez, Nayeli G. Reyes-Nava, Briana E. Pinales, & Anita M. Quintana

https://doi.org/10.33697/ajur.2023.081

ABSTRACT: ZNF143 is a sequence-specific DNA binding protein that regulates the expression of protein-coding genes and small RNA molecules. In humans, ZNF143 interacts with HCFC1, a transcriptional cofactor, to regulate the expression of downstream target genes, including MMACHC, which encodes an enzyme involved in cobalamin (cbl) metabolism. Mutations in HCFC1 or ZNF143 cause an inborn error of cobalamin metabolism characterized by abnormal cbl metabolism, intellectual disability, seizures, and mild to moderate craniofacial abnormalities. However, the mechanisms by which ZNF143 mutations cause individual phenotypes are not completely understood. Defects in metabolism and craniofacial development are hypothesized to occur because of decreased expression of MMACHC. But recent results have called into question this mechanism as the cause for craniofacial development. Therefore, in the present study, we implemented a loss of function analysis to begin to uncover the function of ZNF143 in craniofacial development using the developing zebrafish. The knockdown of znf143b, one zebrafish ortholog of ZNF143, caused craniofacial phenotypes of varied severity, which included a shortened and cleaved Meckel’s cartilage, partial loss of ceratobranchial arches, and a distorted ceratohyal. These phenotypes did not result from a defect in the number of total chondrocytes but were associated with a mild to moderate decrease in mmachc expression. Interestingly, expression of human MMACHC via endogenous transgene prevented the onset of craniofacial phenotypes associated with znf143b knockdown. Collectively, our data establishes that knockdown of znf143b causes craniofacial phenotypes that can be alleviated by increased expression of MMACHC.
KEYWORDS: ZNF143; MMACHC; Vertebrate abnormalities; Cobalamin; cblX-like syndrome; Chondrocytes; Neural crest cells; Hyosymplectic

AJUR Volume 19 Issue 4 (March 2023)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 19 Issue 4 (March 2023) or https://doi.org/10.33697/ajur.2023.069


Links to individual manuscripts, abstracts, and keywords are provided below.

p.3. Ethics of Artificial Intelligence in Society

Emma Johnson, Eloy Parrilla, & Austin Burg
https://doi.org/10.33697/ajur.2023.070
ABSTRACT: Every day, artificial intelligence (AI) is becoming more prevalent as new technologies are presented to the public with the intent of integrating them into society. However, these systems are not perfect and are known to cause failures that impact a multitude of people. The purpose of this study is to explore how ethical guidelines are followed by AI when it is being designed and implemented in society. Three ethics theories, along with nine ethical principles of AI, and the Agent, Deed, Consequence (ADC) model were investigated to analyze failures involving AI. When a system fails to follow the models listed, a set of refined ethical principles are created. By analyzing the failures, an understanding of how similar incidents may be prevented was gained. Additionally, the importance of ethics being a part of AI programming was demonstrated, followed by recommendations for the future incorporation of ethics into AI. The term “failure” is specifically used throughout the paper because of the nature in which the events involving AI occur. The events are not necessarily “accidents” since the AI was intended to act in certain ways, but the events are also not “malfunctions” because the AI examples were not internally compromised. For these reasons, the much broader term “failure” is used. KEYWORDS: Ethics; Artificial Intelligence; Agent-Deed-Consequence (ADC) Model; Principles of Artificial Intelligence; Virtue Ethics; Deontology; Consequentialism; AI Systems

p.13. The By-Product of Ozone from Electrostatic Air Cleaners

Giovanni Cerrato & Nelson Fumo
https://doi.org/10.33697/ajur.2023.071
ABSTRACT: Indoor Air Quality (IAQ) contributes to the health and comfort of people living and working indoors. Poor IAQ can be linked to indoor and outdoor sources of contaminants. One recent solution for improving IAQ is the use of Electrostatic (ES) Air Cleaning technology. An ES air cleaner can be installed in an heating, ventilation, and air conditioning system where it pre-filters large dust particles and shocks smaller particles into a collection tray. However, ES air cleaners have been known to give off ozone as a by-product, which is, itself, an air contaminant. Ozone is found outdoors as product of sunlight combining nitrogen oxides and volatile organic compounds generated from man-made pollution. Indoor ozone concentration will depend on the introduction of outdoor ozone indoors through natural ventilation, mechanical ventilation, and infiltration through the building’s envelope (in order of importance). Two different ES air cleaners, A and B, were installed in the air conditioning system of research House #2 of the TRANE Residential Heating and Cooling Research Lab at the University of Texas at Tyler. A series of ozone experiments were conducted, which included measuring the baseline ozone levels at the research houses with different levels of insulation, observing the increase in ozone due to the powering on of mechanical ventilation, and observing the increase in ozone due to the powering on of the installed ES air cleaners. The baseline ozone levels observed in research house #2, whose envelope is more tightly insulated, was found to be lower than in research house #1 whose envelope is less tightly insulated. With regards to mechanical ventilation, an increase in ozone levels were seen in addition to an even higher increase in ozone levels when the ES air cleaners were powered on in tandem. In terms of the single contribution of the ES air cleaners in raising indoor ozone levels, the data shows that although the ES air cleaners increased the ozone concentration in the house, the levels are not of concern as they were less than the FDA limit on indoor ozone generation. KEYWORDS: Indoor Air Quality; Ozone; Electrostatic Air Cleaner; Infiltration; Mechanical Ventilation; HVAC; Pollutant; Indoor Contaminant

p.31. Student Perceptions of Instructor-Student Rapport and Motivation In Hybrid Courses During COVID-19

Bianca S. Candelaria & Meredith L. Clements
https://doi.org/10.33697/ajur.2023.072
ABSTRACT: The relationship between instructors and their students is essential for developing a classroom climate where students feel motivated to learn. The current study surveyed 658 undergraduate students to examine the relationship between instructor-student rapport and motivation in online and face-to-face classes during the COVID-19 pandemic. Results indicated (1) students experienced more rapport with their instructors during face-to-face classes compared to their online classes, (2) students perceived their motivation was greater during face-to-face classes than in online classes, and (3) there was a significant positive relationship between instructor-student rapport and student motivation in both online and face-to-face classes. This study’s findings lend further support to research that emphasizes the importance of creating a sense of community in online classes, where students feel connected to their instructors and, consequently, motivated to learn. KEYWORDS: Instructor-Student Rapport; Motivation; Hybrid Courses; COVID-19; Online Learning

p.41. “The Strong, Silent Type”: Analyzing the Portrayal of the Cost of Masculine Gender Performances in The Sopranos

Holly Taylor & Anna Curtis
https://doi.org/10.33697/ajur.2023.073
ABSTRACT: Media portrayals of the “strong, silent type” reinforce the expectation that men should not demonstrate or even acknowledge their emotions. This trope, however, reflects more significant societal norms around masculine practices that can have profoundly negative impacts on individual men as well as those around them. Emotional compression (or modern stoicism) is fundamentally different from emotional repression. Emotional compression practices can allow men to process their feelings privately and then communicate their feelings clearly without the distortion of uncontrolled bursts of emotion. The treatment of mental health and masculinity in Season 5 of The Sopranos “holds up a mirror” to the costs of emotional repression for men as part of masculine gender performances. The show highlights, sometimes quite brutally, the costs of emotional repression to men and the people around them. In doing so, the content of the show implies that therapy could help men learn to face their feelings and alleviate their suffering as well as that of their families, though only if men are willing to face the feelings of vulnerability that come with having emotions. KEYWORDS: Stoicism; Alexithymia; Hegemonic masculinity; Emotional repression; Mental health; Gender performances

p.53. A Review of the Effect of Estrogen on Immune Efficacy in Zebrafish (Danio rerio) with Comparisons to Human and Murine Homologs

Michael S. Chembars & Lindsey C. Stevenson
https://doi.org/10.33697/ajur.2023.074
ABSTRACT: A review was conducted on current research surrounding the effect of estrogen, and the estrogen receptor, on immune development. Estrogen can regulate many processes and genes throughout immune development, from modulating complement activation and regulating genes crucial for hematopoiesis, to elevating toll-like receptor gene expression. Estrogen has also been shown to have a pronounced effect on regulating certain cancers through inducing macrophage infiltration. It has also been demonstrated to play an important role in the regulation of microRNAs that are important for proper immune development. A greater understanding of this hormone’s effect gained through the zebrafish model can lead to the development of better practices to improve both human and ecological health. Contemporary reviews typically examine the effect of estrogen-like compounds (oftentimes referred to as estrogenic endocrine disrupting compounds) on a sequestered part of immune system development. A distinct lack of cohesion exists in combining contemporary and past reports of the effects of estrogen on various aspects of immune system development in zebrafish. This review serves to fill that gap in knowledge, and to provide a gateway for other researchers interested in this topic. KEYWORDS: Zebrafish; Immune development; Zebrafish immunology; Estrogen; Estrogen receptor; Autoimmunity; Altered signaling; Hematopoiesis

AJUR Volume 19 Issue 3 (December 2022)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 19 Issue 3 (December 2022) or https://doi.org/10.33697/ajur.2022.063


Links to individual manuscripts, abstracts, and keywords are provided below.

p.3. Comparison of Genotypic and Phenotypic Predictions for Heavy Metal Resistance in Salmonella enterica and Escherichia coli

Jeevan Rivera-Díaz, Haley Phillippi, Nyduta Mbogo, Erin M. Nawrocki, & Edward G. Dudley

https://doi.org/10.33697/ajur.2022.064

ABSTRACT: Salmonella enterica and Escherichia coli are two pathogenic bacteria of worldwide importance that can infect the gastrointestinal tract. Contamination in the food supply chain is an area of concern. Animal feed may be supplemented with essential trace elements, which function as nutritional additives to promote growth & health and optimize production. Bacteria have acquired many metal resistance genes to adapt to the exposure of metals. In this study, our objectives were to evaluate in S. enterica and E. coli, the correlation between the resistance genotype and phenotype to certain heavy metals, and the ability of conjugative plasmids to transfer antimicrobial resistance genes (AMRGs) and heavy metal resistance genes (HMRGs). A total of 10 strains, five S. enterica and five E. coli, were used for this study. Minimal inhibitory concentrations (MICs) were determined for heavy metals: copper, silver, arsenic, and tellurite. The tested isolates showed resistance to copper (5/10; 50%), arsenic (7/10; 70%), and silver (9/10; 90%). Cohen’s Kappa statistics were used to analyze genotype to phenotype agreements. Among the 10 strains sampled, the accordance between geno- and phenotypic heavy metal resistance was fair for copper (kappa = 0.4), none to slight for arsenic (kappa = 0.19) and tellurite (kappa = 0), and no agreement for silver (kappa = -0.19). The transfer of HMRGs was determined in a conjugation experiment performed for all five Salmonella strains as donors using mixed broth cultures. Transconjugants were obtained only from the genotypically tellurite-resistant strain PSU-3260, which yielded a transfer frequency of 10⁻³ transconjugants per donor. In such strain, the tellurite-resistant genes reside on an IncHI2-type plasmid that shares high DNA sequence identity with known HMRG-disseminating Salmonella plasmids. Our results indicated no considerable correlation between the geno- and phenotypic resistance towards heavy metals in the sampled S. enterica and E. coli. The necessity of research in this area is supported by the lack of standardized protocols and MIC clinical breakpoints for heavy metals.

KEYWORDS: Heavy metal; resistance; Salmonella; E. coli; agriculture; genotype; phenotype; MIC

p.17. Preventing the Activation of a Stress Gene Response in Escherichia coli Using Acetate, Butyrate, and Propionate

Kaylee M. Weigel, Kathleen M Ruff-Schmidt, Birgit M. Prüß, & Danielle L J Condry

https://doi.org/10.33697/ajur.2022.065

ABSTRACT: Regulation of microbial symbiosis in the human intestinal tract is imperative to maintain overall human health and prevent dysbiosis-related diseases, such as inflammatory bowel disease and obesity. Short-chain fatty acids (SCFA) in the intestine are produced by bacterial fermentation and aid in inflammation reduction, dietary fiber digestion, and metabolizing nutrients for the colon. SCFA, notably acetate, butyrate, and propionate, are starting to be used in clinical interventions for GI diseases. While acetate has been shown to mitigate a stress response in the proteome of Escherichia coli cells, little is known about the effects of butyrate and propionate on the same cells. This study aims to evaluate the effects that butyrate and propionate have on the activation of stress promoters in E. coli when induced with a known stressor. Three different strains of E. coli containing the pUCD615 plasmid were used, each with a different promoter fused to the structural genes of the lac operon on the plasmid. Each promoter detected a unique stress response: grpE’::lux fusion (heat shock), recA’::lux fusion (SOS response), and katG’::lux fusion (oxidative damage). Activation of these stress promoters by treatment groups resulted in the emission of bioluminescence which was quantified and compared across treatment groups. All three SCFAs at 25 mM added to cultures prior to stressing the bacteria caused significantly lower bioluminescence levels when compared to the stressed culture without prior addition of SCFA. This indicates that these SCFAs may reduce the stress response in E. coli.

KEYWORDS: Short-chain fatty acids; acetate; butyrate; propionate; Escherichia coli; stress response; Vibrio fischeri luxCDABE; grpE; katG; recA

p.27 Quantification of Microfibers from Marine Sediments from Three Locations in Southern California: An Exposed Beach (Ventura County), a Watershed (Los Angeles County), and an Enclosed Harbor (Orange County)

Adrianna Ebrahim & Mia LeClerc

https://doi.org/10.33697/ajur.2022.066

ABSTRACT: Microfibers are small (<5 mm) fibers made of synthetic materials that are ubiquitous in the environment. The purpose of this observational study was to quantify the number of microfibers in marine sediments and determine which locations have the highest risk for this type of pollution. Sediment samples were taken from three locations in Southern California (Sycamore Watershed, Ventura State Beach Jetty, and Newport Beach Harbor) to determine which had the highest number of microfibers. It was hypothesized that microfibers would be found at each sample site and that the most microfibers would be found at Sycamore Watershed due to its proximity to a wastewater discharge point. The microfibers were separated from the sediment through a process of stratification and filtration and analyzed by a one-way ANOVA and Tukey’s test. Per sample, there was an average of 111.5 (土99.3, n=14) microfibers found per sample at Sycamore Watershed, 59 (土17.4, n=18) at Newport Beach Harbor, and 53 (土14.4, n=18) at Ventura State Beach Jetty. A total of 3,590 microfibers were found from all three sample sites. Analysis revealed that Sycamore Watershed had significantly more microfibers than any other site (p<.05). It is likely that Sycamore Watershed had the most microfibers because of its proximity to a sewage-sludge disposal site that contains the polluted water from our washing machines. In conclusion, microfibers are polluting the sediments in harbors, open coastlines, and watersheds in California, negatively affecting the ecosystems in these areas.

KEYWORDS: Microfiber; Microplastic; Macroplastic; Marine Pollution; Synthetic Materials; Wastewater Treatment Plants; Sediments; Watershed; Harbor; Jetty

p. 37. Stabilization of Cisplatin via Coordination of Ethylenediamine

Samantha L. Rea, Alexia Smith, Brooke Hornberger, Grace Fillmore, Jeremy Burkett, & Timothy Dwyer

https://doi.org/10.33697/ajur.2022.067

ABSTRACT: While the chemotherapeutic cisplatin is used to treat a variety of cancers, metal toxicity and cisplatin resistance via genetic and epigenetic changes limits its use and calls for alternative therapies. To combat the observed toxicities and create a more stable compound, which avoids isomerization into a trans configuration, three cisplatin analogues including cispalladium, dichloro-(ethylenediamine)-platinum(II), and dichloro-(ethylenediamine)-palladium(II) were synthesized as potential cisplatin alternatives. Each compound was evaluated for cytotoxicity on SK-OV-3 cells against cisplatin. Synthesis of dichloro-(ethylenediamine)-platinum(II) yielded 20.5% of the theoretical yield, while dichloro-(ethylenediamine)-palladium(II) yielded 49.1%. Results from the cytotoxicity trial revealed that cispalladium was not effective against SK-OV-3 cells, and dichloro-(ethylenediamine)-palladium had minimal effects. The dichloro-(ethylenediamine)-platinum(II) was the most efficacious with an IC50 value of 0.77 µg/ml compared to the IC50 of 0.61 µg/ml for cisplatin. With a similar IC50 to cisplatin, these results suggest that dichloro-(ethylenediamine)-platinum(II) has the potential to serve as a cisplatin alternative for cancer patients who develop resistance following their clinical course of cisplatin. Future studies on the cytotoxicity of dichloro-(ethylenediamine)-platinum(II) to induce cell death on cisplatin-resistance cell lines are necessary to determine the ability of the compound to be utilized as a cisplatin alternative.

KEYWORDS: Cisplatin; Ovarian Cancer; SK-OV-3; Drug Resistance; Stability; Palladium; Ethylenediamine; Cispalladium; Dichloro-(ethylenediamine)-platinum(II); Dichloro-(ethylenediamine)-palladium(II)

p.47. Novel Interactors of the SH2 Domain of the Signaling Adaptors CRK and CRKL Identified in Neuro2A Cells

Caroline M. Dumas, Anna M. Schmoker, Shannon R. Bennett, Amara S. Chittenden, Chelsea B. Darwin, Helena K. Gaffney, Hannah L. Lewis, Eliana Moskovitz, Jonah T. Rehak, Anna A. Renzi, Claire E. Rothfelder, Adam J. Slamin, Megan E. Tammaro, Leigh M. Sweet, & Bryan A. Ballif*

https://doi.org/10.33697/ajur.2022.068

ABSTRACT: CT10 regulator of kinase (CRK) and CRK-like (CRKL) form a family of signaling adaptor proteins that serve important roles in the regulation of fundamental cellular processes, including cell motility and proliferation, in a variety of cell types. The Src Homology 2 (SH2) domain of CRK and CRKL interacts with proteins containing phosphorylated tyrosine-X-X-proline (pYXXP) motifs, facilitating complex formation during signaling events. A handful of CRK/CRKL-SH2-specific interactors have been identified to date, although in silico analyses suggest that many additional interactors remain to be found. To identify CRK/CRKL-SH2 interactors with potential involvement in neuronal development, we conducted a mass spectrometry-based proteomics screen using a neuronal cell line (Neuro2A, or N2A). This resulted in the identification of 132 (6 known and 126 novel) YXXP-containing CRK/CRKL-SH2 interactors, of which 77 were stimulated to bind to the CRK/CRKL-SH2 domain following tyrosine phosphatase inhibition. Approximately half of the proteins identified were common interactors of both the CRK- and CRKL-SH2 domains. However, both CRK family member SH2 domains exhibited unique binding partners across experimental replicates. These findings reveal an abundance of novel neuronal CRK/CRKL-SH2 domain binding partners and suggest that CRK family SH2 domains possess undescribed docking preferences beyond the canonical pYXXP motif.

KEYWORDS: CRK; CRKL; SH2; LC-MS/MS; Proteomics; Neurodevelopment; Signal Transduction

SUPPLEMENT 1 (Figures)

SUPPLEMENT 2 (Tables)

AJUR Volume 19 Issue 2 (September 2022)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 19 Issue 2 (September 2022) or https://doi.org/10.33697/ajur.2022.058


Links to individual manuscripts, abstracts, and keywords are provided below.

p.3. Evaluating Driveway Cross Slopes and Social Equity in Cedar City, UT

Brock Anderson* & Jamie Spinney

Department of Geosciences, Southern Utah University, Cedar City, UT

https://doi.org/10.33697/ajur.2022.059

Student: brock20anderson00@gmail.com*

Mentor: jamie.spinney@suu.edu

ABSTRACT

The Americans with Disabilities Act (ADA) is the most comprehensive law governing accessibility, and it requires local governments to develop transition plans to become compliant. Among the key ADA requirements is a continuous unobstructed pedestrian circulation network that consists of a sidewalk that has a cross slope of no more than two degrees. The primary objective of this research was to evaluate whether driveway cross slopes in Cedar City were ADA compliant, so a digital level was used to measure a random sample of driveway cross slopes. A secondary objective was to determine whether there is evidence of social inequities in Cedar City’s pedestrian environment. The estimated value of each residential property (a proxy for income) was retrieved from Zillow® to evaluate the statistical relationship between incomes and driveway cross slopes. The results of this study indicate that there was no widespread evidence of social inequities. However, most driveway cross slopes (78.8 percent) were not ADA compliant and, thus, require retrofitting that should incorporate more widespread use of sidewalk buffer strips. The results also highlight priority areas for sidewalk improvements and can be used to inform a transition plan for sidewalk enhancements and funding.

KEYWORDS

Social Equity; ADA; Sidewalks; Advocacy Planning; Driveway Cross Slope; Walkability

p.11. Conversations About Mental Health and Well-being During the COVID-19 Pandemic: Why and How Restaurant Employees Talk With Each Other and Managers

Anamaria Tepordei* & Kirsten Foot

Department of Communication, University of Washington, Seattle, WA

https://doi.org/10.33697/ajur.2022.060

Student: anamaria.tepordei@outlook.com*
Mentor: kfoot@uw.edu

ABSTRACT
Restaurant employees in the United States have experienced unprecedented challenges to their mental health and well-being (MHW) during the COVID-19 pandemic, yet little is known about communication regarding MHW in the restaurant industry. Drawing on health, organizational, and interpersonal communication concepts, this exploratory, survey-based study probed whether, how, and why or why not restaurant employees in western Washington State conversed about MHW with one another and their managers during the winter of 2021. Key findings include that there are many reasons why some restaurant employees do not engage in conversations about MHW with other members of the workplace. However, when such conversations do occur, they are typically mutual, positive, and relationally-oriented—more so among coworkers than between employees and managers. Additionally, both coworkers and managers are sources of social support and resource exchange during these conversations, although the evidence is stronger among coworkers. Our findings contribute to the extant literature on mental health communication in the workplace and demonstrate the merit in more closely examining superior-subordinate and coworker communication about personal and sensitive topics, like MHW. Comparative analysis of employees’ MHW-related communication with coworkers versus managers revealed both similarities and differences that carry implications for managerial practice and future research.

KEYWORDS
Mental Health and Well-being (MHW); Disclosure; Superior-subordinate Communication; Peer Coworker; Social Exchange; Social Support; Interpersonal Communication Motives (ICM), Restaurant Employees

p. 33. Differential Expression of Hub Genes and Activation of p53 by Anti-cancer Compound Curaxin CBL0137

Tanvi Patel*, Rochelle Ratner, & Niharika Nath

Department of Biological & Chemical Sciences, New York Institute of Technology, New York, NY

https://doi.org/10.33697/ajur.2022.061

Students: tpatel60@nyit.edu*, rratne02@nyit.edu

Mentor: nnath@nyit.edu

ABSTRACT

Cancer is a global concern and there is a need for effective drugs. CBL0137 is a small water-soluble molecule and a new second-generation compound in the family of curaxins with potential anti-cancer activity. Curaxins in general, including CBL0137 intercalate into DNA, and act by targeting the histone chaperone ‘facilitates chromatin transcription’ (FACT) complex and have the potential to treat tumors by reducing the growth of cancer cells which is shown in a variety of cell lines and animal models. CBL0137 is found to activate the tumor suppressor gene p53. However, the mechanism of p53 activation is poorly understood. Utilizing bioinformatics analysis on available datasets of CBL0137 treated cancer cells of glioma, cervical and multiple myeloma, differentially expressed genes (DEGs) that may lead to the activation of p53 were examined. Three GEO datasets of cells treated with various concentrations of CBL0137 were analyzed, namely HSJD-DIPG007 (GSE153441), MM1.S (GSE117611) and HeLa S3 (GSE117611). The DEGs were identified based on p-values less than 0.05, logFC values greater than 1 and less than -1 and analyzed using GEO2R, Enrichr, and STRING, and data visualization was performed on Tableau. Compared to the controls, a total of 229, 1425, and 1005 genes were upregulated while 368, 2322, and 1673 genes were downregulated for HSJD-DIPG007, MM1.S and HeLa S3 datasets, respectively. Further collective analysis revealed a total of 38 common DEGs among the three datasets. Using Enrichr and STRING on these 38 DEGs, seven hub genes were obtained, SKP2, RGS16, CSRP2, CENPA, HJURP, DTL, and HEXIM1 with these possible mechanisms:  inhibition of AKT phosphorylation by upregulated genes RGS16 and CSRP2, p300-mediated acetylation of p53 via SKP2, inhibition of MDM2 by DTL downregulation and HEXIM1 upregulation, and inhibition of AURKB via CENPA and HJURP downregulation. This study analyzed the three datasets and highlighted how these identified hub genes may play a role in leading to p53 activation by CBL0137.

KEYWORDS

Curaxin; CBL0137; Differentially Expressed Genes; Cancer; p53; Glioblastoma; Cervical; Myeloma

p. 43. Cemetery Analysis of Whitewater, WI

David H. Nehlsen

Department of Political Science and Philosophy at the University of Green Bay, WI

https://doi.org/10.33697/ajur.2022.062

Students: nehldh03@uchicago.edu*

Mentor: weinscha@uwgb.edu

ABSTRACT

Procedures and customs surrounding funerals, burial, and grave marking vary widely by time period, location, culture, and religion, among many other factors. This project investigated the gravestone customs of cemeteries in Southern Wisconsin, USA. Utilizing a dataset of 500 gravestone samples collected from cemeteries in Whitewater, WI, the aim of this project was to objectively measure how people choose to remember their dead and how these practices have evolved over the years. Because of the decline in American religiosity in recent decades, the expectation of this project was to see the usage of religious symbols decline. Based upon this analysis, this does not appear to be the case. Practices such as the recording of one’s name and year of birth/death have remained constant; however, other customs of remembrance, such as the use of religious symbols and the recording of one’s date of marriage, have shifted dramatically over the years, reflecting the evolution of society and culture.

KEYWORDS

Cemetery; Symbols; Funeral; Thanatology; Death; Demography; Monuments; History

AJUR Volume 19 Issue 1 (June 2022)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 19 Issue 1 (June 2022) or https://doi.org/10.33697/ajur.2022.053


Links to individual manuscripts, abstracts, and keywords are provided below.

p.3 Myrica cerifera, a Medicinal Plant of the Lumbee Tribe, has Antibacterial and Nematicidal Properties

Ashley Edwards, Kazhmiri Deberry, Hannah Mariani, Darian H. Taylor, Nicholas J. Cochran, Ana C. Barrios Sosa, Andrea Regan Scott, R. Thomas Williamson, Cornelia Tirla, Conner Sandefur, & Courtney Carroll Alexander

https://doi.org/10.33697/ajur.2022.054

ABSTRACT: Currently threatening the world of medicine is a growing number of antibiotic-resistant diseases. More specifically, bacteria and nematodes have gained resistance to many of the world’s leading antibiotics and nematicides, respectively, making infections more difficult to treat. Subsequently, these parasitic organisms are able to continue damaging crops and other living organisms like humans without strong interference. To help people and the environment, the development of new and novel antibiotics is vital. Previous research suggests that phytochemicals are a potential solution that will not only help inhibit bacterial growth but also reduce nematode survival. We hypothesized that Myrica cerifera, a plant often used by the Lumbee tribe to treat illness, possesses antibacterial and nematicidal properties. To answer our hypothesis, we began by collecting plant specimens to extract material for biological assays and to subsequently isolate and elucidate the structures of active components. The extract was evaluated for antibacterial properties with an agar diffusion assay and then nematicidal properties using Caenorhabditis elegans. M. cerifera extract was added onto an agar lawn at various doses, and the nematodes’ lifespans were scored. The findings of this study show that extracts of this plant, more commonly referred to as ‘wax myrtle’, do significantly decrease the lifespan of C. elegans and increase the zone of inhibition for Staphylococcus epidermidis and Staphylococcus aureus. In addition, two compounds were isolated and characterized through chemical extraction, chromatographic separation, and spectroscopic analysis. These compounds could potentially be used to treat bacterial and nematode infections.

KEYWORDS: Antibacterial; Antimicrobial; Caenorhabditis elegans; Plant extract; Myrica cerifera; Nematicidal; NMR; Phytochemical

Supplemental Data for https://doi.org/10.33697/ajur.2022.054

p.13 State Adoption of Cryptocurrency: a Case Study Analysis of Iran, Russia, and Venezuela

Rose Mahdavieh

https://doi.org/10.33697/ajur.2022.055

ABSTRACT: The emergence of digital currency is becoming prevalent in the age of globalization – specifically, cryptocurrencies, a subset of digital currency that encompass revolutionary technology. This study postulates that certain governments are more prone to adopting cryptocurrencies, especially those seeking to eschew international sanctions and protect corrupt practices. Three comparative case studies focus on countries (Iran, Russia, and Venezuela) that share attributes that result in adopting what has been called “native cryptocurrencies”: corruption, GDP level, economic volatility, and Western sanctions.

KEYWORDS: Cryptocurrency; Blockchain; Political Science; Law; Foreign Sanctions; Government; Iran; Russia; Venezuela

p23. Salinity Affects Wound Healing in Wild Common Bottlenose Dolphins (Tursiops truncatus)

Brianna Hurst & Dara N. Orbach

https://doi.org/10.33697/ajur.2022.056

ABSTRACT: Dolphins are often individually identified by unique naturally-acquired markings. Identification becomes difficult when markings heal, or new scars appear. As salt accelerates wound healing in many organisms, the diminishment of scars on common bottlenose dolphins (Tursiops truncatus) residing in varying natural salinities was determined. South Texas contains the only hypersaline lagoon in the USA, located adjacent to hyposaline waters, with genetically distinct populations of dolphins in the two environments. Photographs of dolphin dorsal fins were collected, and scar stability over time was determined and compared by measuring changes in the relative lengths and surfaces of scars. All scars on dolphins in the hypersaline lagoon completely diminished between three to six years, while scars on dolphins in the hyposaline bay ranged in the amount of fading between three to six years. Data from this case study indicate that high salinity may increase the healing speed of wounds on common bottlenose dolphins compared to low salinity, although a larger sample size is needed for robust statistical comparison. Scar diminishment is an important consideration in determining the temporal reliability of photo identification.

KEYWORDS: Bottlenose dolphin; Corpus Christi Bay; healing; hypersaline; Laguna Madre; photo-identification; salinity; scar

p.31 Validation of Accelerometer-Based Estimations of Energy Expenditure During High-Intensity Interval Training

Nicholas Remillard, Marisa Mulvey, Gregory Petrucci Jr, & John R Sirard

https://doi.org/10.33697/ajur.2022.057

ABSTRACT: Accelerometers are used to assess free-living physical activity (PA) and energy expenditure (EE). Energy expenditure estimation algorithms have been calibrated using steady-state exercise. However, most free-living PA is not steady-state. Objective: The purpose of this study was to discern the differences between criterion-measured and accelerometer-estimated EE (kCals) during a non-steady-state High-Intensity Interval Training (HIIT) session. Methods: Recreationally active adults (N=29, 18-30 years) completed one of two HIIT protocols. Each participant wore ActiGraph GT3X+ accelerometers on the right hip and non-dominant wrist while EE was measured using portable indirect calorimetry. Data analysis was conducted using custom R scripts and bias [95% CIs] to determine significant differences between indirect calorimetry and EE estimates using previously developed algorithms. Results: All accelerometer algorithms underestimated EE during recovery intervals (range; -4.31 to -6.55 kCals) and overestimated EE during work intervals (0.57 to 5.70 kcals). Over the whole HIIT session, only the Hildebrand wrist method was not significantly different from the criterion measured EE. Conclusion: Current ActiGraph EE estimations based on steady-state activities underestimate EE during recovery periods of treadmill HIIT sessions. Future studies should investigate accelerometer signals immediately after high-intensity bouts to more accurately predict EE of the subsequent recovery period.

KEYWORDS: ActiGraph; Accelerometer; HIIT; Indirect calorimetry; EPOC; Energy expenditure; Non-steady state; Calories

AJUR Volume 18 Issue 4 (March 2022)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 18 Issue 4 (March 2022) or https://doi.org/10.33697/ajur.2022.050


Links to individual manuscripts, abstracts, and keywords are provided below.

p.3. The Effects of the NBA COVID Bubble on the NBA Playoffs: A Case Study for Home-Court Advantage
Michael Price & Jun Yan
https://doi.org/10.33697/ajur.2022.051
ABSTRACT: The 2020 NBA playoffs were played inside of a bubble at Disney World because of the COVID-19 pandemic. This meant that there were no fans in attendance, games were played on neutral courts and no traveling for teams. In theory, these conditions should remove home-court advantage from the games. This setting generated discussion and concern, as analysts and fans debated the possible effects it may have on the outcome of games. Home-court advantage has historically played an influential role in NBA playoff series outcomes. The 2020 playoffs provided a unique opportunity to study the effects of the bubble and home-court advantage by comparing the 2020 season with the seasons in the past. While many factors contribute to the outcome of games, points scored is the deciding factor of who wins. Thus, scoring is the primary focus of this study. The specific measures of interest are team scoring totals and team shooting percentage on two-pointers, three-pointers, and free throws. Comparing these measures for home teams and away teams in 2020 vs. 2017-2019 shows that the 2020 playoffs favored away teams more than usual, particularly with two-point shooting and total scoring.
KEYWORDS: NBA; NBA Covid; NBA Bubble; Homecourt Advantage

p.15. Internalizing Symptoms in Children Exposed to Adversity: Examining Associations with Resilience, Social Support, and Community Cohesion
Rachel Stobbe, Taylor Napier, Debra Bartelli, & Kathryn H. Howell
https://doi.org/10.33697/ajur.2022.052
ABSTRACT: Exposure to adverse childhood experiences (ACEs) contributes to increased rates of psychopathology in youth. Specific environmental factors have been linked to improved functioning following adversity, but few studies have taken a social-ecological approach to examine how resilience, social support, and community cohesion may be associated with internalizing problems (i.e., anxiety, depression) in young children. The current study included 49 children between the ages of 8 and 13 (Mage = 10.43, SD = 1.57; 55.1% male; 95.8% Black or African American) who were recruited from four community programs in the Midsouth, United States that serve families experiencing adversity. Regarding income, 77.3% of youth’s caregivers reported an annual household income under $15,000. Almost all children reported experiencing at least one ACE (92.6%). Two linear regression models were run to assess how resilience, social support, and community cohesion were related to youth’s depression and anxiety symptoms while controlling for ACEs and family income. The model examining depression was significant, (F (5, 48) = 4.16, p < .01, R2 = .33) with fewer reported ACEs (β = 1.55, p < .02) and higher resilience (β = -.73, p = .01) associated with lower depressive symptoms. The model assessing anxiety was not significant. Results indicate that personal resilience may be a key target for intervention in children exposed to ACEs as efforts to strengthen individual resources (e.g., self-efficacy, emotion regulation skills) could be linked to reduced psychopathology.
KEYWORDS: Adverse Childhood Experiences; Social Ecology; Resilience; Social Support; Community Cohesion; Internalizing Symptoms; Anxiety; Depression

AJUR Volume 18 Issue 3 (December 2021)

Click on this link to download the full high-definition interactive pdf for AJUR Volume 18 Issue 3 (December 2021)


Links to individual manuscripts, abstracts, and keywords are provided below.

p. 3. An Optimal Control Experiment for an SEIRS Epidemiological Model
Tanner Snyder & Ryan Nierman
Department of Mathematics and Computer Science, Madonna University, Livonia, MI
https://doi.org/10.33697/ajur.2021.047
ABSTRACT: This work studies an optimal control model for a discrete-time Susceptible/Exposed/Infective/Removed/Susceptible (SEIRS) deterministic epidemiological model with a finite time horizon and changing population. The model presented converts a continuous SEIRS model that would typically be solved using differential equations into a discrete model that can be solved using dynamic programming. The discrete approach more closely resembles real life situations, as the number of individuals in a population, the rate of vaccination to be applied, and the time steps are all discrete values. The model utilizes a previously developed algorithm and applies it to the presented SEIRS model. To demonstrate the applicability of the algorithm, a series of numerical results are presented for various parameter values.
KEYWORDS: Control; Cost; Discrete; Disease; Epidemiology; Minimization; Modeling; Optimality; SEIRS; Vaccination

p. 15. Factors Associated with Surgery Among South Asian American and Non-Hispanic White Women with Breast Cancer
Lydia Lo & Jaya M. Satagopan
Department of Industrial and Systems Engineering, School of Engineering, Rutgers University,New Brunswick, NJ
Department of Biostatistics and Epidemiology & Center for South Asian Quantitative Health and Education, School of Public Health, Rutgers University, New Brunswick, NJ
https://doi.org/10.33697/ajur.2021.048
ABSTRACT: South Asian American (SA) women are diagnosed with more aggressive breast cancer than non-Hispanic White (NHW) women. Understanding the factors associated with the types of surgery received by these women sheds light on disease management in these culturally distinct populations. We used data on age at diagnosis, stage, grade, estrogen and progesterone receptors, and surgery from 4,590 SA and 429,030 NHW breast cancer cases in the Surveillance, Epidemiology and End Results (SEER) program. We used logistic regression with surgery as the binary outcome (subcutaneous, total, or radical mastectomy (STRM) versus partial mastectomy, no, unknown or other (PNUM)) and included additive effects of all the variables and interactions of age, stage, grade, and estrogen and progesterone receptors with race/ethnicity. Type I error of 5% was used to assess statistical significance of the effects. SA were significantly more likely than NHW cases to receive STRM relative to PNUM surgery among women diagnosed at or after age 50 years and having localized stage disease (Odds Ratio (OR) = 1.27, 95% Confidence Interval (CI) = 1.06 – 1.52). Further, SA were significantly less likely than NHW cases to receive STRM relative to PNUM surgery among those diagnosed before age 50 years and having regional or distant stage disease (OR = 0.75, 95% CI = 0.59 – 0.95 for age at diagnosis < 40 years; OR = 0.77, 95% CI = 0.62 – 0.95 for age at diagnosis 40-49 years). The type of surgery received by SA and NHW women differ according to age at diagnosis and disease stage. 
KEYWORDS: Breast Cancer; Surgery; Cancer Health Equity; Disease Characteristics; South Asian American; Non-Hispanic White; Logistic Regression; Interaction

p. 25. The Effect of Perceived Uncertainty on Competitive Behavior
Duncan James Drewry & Zachary Reese
Weinberg Institute for Cognitive Science, University of Michigan, Ann Arbor, MI
Department of Psychology, University of Michigan, Ann Arbor, MI
https://doi.org/10.33697/ajur.2021.049
ABSTRACT: How do people behave in the face of uncertainty? Some studies suggest that even when they are unaware of how others will behave, people default to cooperative behavior; however, other research suggests that uncertainty leads to more competitive behavior. Little research has examined how individual differences moderate such behavioral decisions. This study proposes that a stable (dispositional) sense of justice may, ironically, lead to more competitive behavior. Specifically, people who score highly in belief in a just world, system justification, and religiosity, and low in ambiguity tolerance may be more inclined to compete rather than cooperate because they believe people who experience positive outcomes deserve those outcomes regardless of the means taken to achieve them. Across two studies, participants (N = 288) engaged in a prisoner’s dilemma game — a task where they must choose to compete or cooperate — and completed the aforementioned individual difference measures. Results show that people tended to cooperate, but those high in system justification and belief in a just world were more likely to compete. In other words, people with a strong sense of cosmic justice were likely to exhibit competitive behavior under uncertain conditions.
KEYWORDS: Ambiguity Tolerance; Competition; Cooperation; Just World Beliefs; Prisoner’s Dilemma; Prosocial Behavior; Religiosity; System Justification; Uncertainty