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Global Existence of Solutions for A Class of Nonlocal Reaction-Diffusion Systems and Their Diffusive Limit
No full textIn this work, we study the global existence of solutions for a class of semilinear nonlocal reaction-diffusion systems with m components on a bounded domain Ω in R^n with smooth boundary. The initial data is assumed to be componentwise nonnegative and bounded, and the reaction vector field associated with the system is assumed to be quasi-positive and satisfy a generalized mass control condition. We obtain global existence and uniqueness of componentwise nonnegative solutions. With the additional assumption that the reaction vector field satisfies a linear intermediate sums condition, we employ an Lp energy type functional to establish the uniform boundedness of solutions in Lp(Ω) for all 2 ≤ p < ∞ independent of the nonlocal diffusion operator for our system in Lp space for 2 ≤ p < ∞. This allows us to generalize a recent diffusive limit result of Laurencot and Walker [65]. We, also analyze a class of m component reaction-diffusion systems in which some of the components diffuse nonlocally and the other components diffuse locally, where the latter components satisfy homogeneous Neumann boundary conditions. Under various assumptions, we establish global existence and uniqueness of componentwise nonnegative solutions by using duality arguments. Finally, we numerically verify our diffusive limit result. We also numerically solve the reaction-diffusion systems with a mixture of nonlocal and local diffusion and show the visual difference of its solutions with the system in which all components diffuse nonlocally
What is the Effect of Cultivated Native Microbial Soil Amendments on Coastal Dune Restoration Efforts?
No full textSand dunes protect coastal communities from rising sea levels and erosion during storms. When sand dunes are destroyed and need restoration, restoration attempts are often unsuccessful because existing sand lacks a sufficient microbial community to support the plants. Native soil amendments from healthy dune habitats may be used to inoculate the restoration site with helpful microbes. But practically, collecting healthy soil for restoration projects each times is challenging. If these amendments can be cultivated with sterile play sand and stored for long periods of time while maintaining their effects, amending the soil in this way could be adapted by restoration projects. The results of previous experiments performed with these amendments immediately after collection found a more than two-fold increase in total biomass with certain amendments. This experiment tests the same amendments after 2.5 years of cultivation in the lab to determine the feasibility of native microbial amendments as a restoration tool.Biology and Biochemistry, Department ofHonors Colleg
Hospital Pharmacists’ Perspectives on Adverse Drug Reaction Reporting in Developed and Developing Countries: A Comparative Pilot Study
No full textAdverse drug reactions (ADRs) significantly affect patient safety and healthcare spending worldwide. Hospital pharmacists are uniquely positioned to address ADRs due to their crucial role in medication management. However, underreporting remains a global concern, especially in developing countries, where pharmacovigilance systems are inadequately developed. Therefore, this pilot study aimed to evaluate and compare the knowledge, attitudes, perceived barriers, and facilitators regarding ADR reporting by hospital pharmacists in a developed (US) and a developing (Pakistan) country. A cross-sectional survey was conducted, using a pre-validated questionnaire. The pharmacists, possessing a minimum of one year’s hospital experience, were selected via convenience sampling. Out of 151 respondents, included in the final analysis (US: n = 51; Pakistan: n = 100), the majority were female (62.3%), aged 29–35 years (38%), and possessed a Pharm. D degree (49.7%). The knowledge (US: 6.03 ± 0.27 vs. Pakistan:5.69 ± 0.25, p-value = 0.193) and attitude scores (US: 32.02 ± 0.73 vs. Pakistan: 32.63 ± 0.67; p-value = 0.379) exhibited no significant differences between the groups. Nonetheless, barriers at both the individual and systemic levels were more pronounced in the developing country. Important facilitators reported were mobile applications for ADR reporting, specialized training, and intuitive reporting tools. In conclusion, we found that pharmacists in both settings exhibit comparable knowledge and positive attitudes towards ADR reporting, though specific contextual barriers are present. Interventions customized to the local hospital infrastructure are crucial for enhancing ADR reporting, particularly in resource-constrained settings
Respiratory Health at the Fenceline: The Shadow of Industry and Primary Care Access in Harris County
No full textFence-line communities are geographical areas situated adjacent to highly polluting industrial facilities such as refineries, chemical plants, and manufacturing sites. The density of these facilities can increase a community's exposure to pollutants and the risk of developing chronic respiratory diseases. To assess the risk of respiratory conditions in such communities, it is crucial to identify the locations and densities of polluting facilities. This information helps estimate the extent of air pollutant exposure. Additionally, access to primary care is vital for managing chronic conditions, as these typically require ongoing medical support. In Harris County, systemic redlining and chronic, economic disinvestment have disproportionately affected minority Black and Hispanic communities. In areas with a high density of polluting facilities, there is often a higher rate of chronic respiratory diseases and fewer primary care physicians. This disparity highlights the urgent need for targeted health interventions and policy changes to address environmental and healthcare inequities.Honors Colleg
Hypoxia-Identifying Explainable AI for Risk Tracking in Fetal Cardiotocography
No full textCardiotocography (CTG) is a technique used to monitor the health of a fetus by measuring fetal heart rate (FHR) and uterine contractions (UC), and is often used during birth to help identify fetal hypoxia. Because differences in CTG interpretation among health professionals can complicate the comprehension of real-time data, CTG analysis using machine learning (ML) can be a cost-effective and accessible approach for facilitated identification of fetal hypoxia. The objective of this study was to develop an explainable ML model capable of correctly classifying cases as Normal, Suspect, or Pathologic (NSP) using 2126 NSP instances and 23 variables based on patterns in UC and FHR (UC Irvine ML Repository). A supervised learning approach was implemented, wherein 13 algorithms of various types were employed and evaluated in terms of F1 score, as well as accuracy, precision, and recall. An F1 score of 0.9526 was reached, which was comparable with a benchmark value of 0.9561 found in previous literature. Finally, Shapley Additive Explanations (SHAP) and Local Interpretable Model-Agnostic Explanations (LIME) were implemented to determine feature importance in the models, revealing the most significant variables in the model's predictions and quantifying the extent of their influence on the predicted NSP classification. Through an approach which equally emphasizes performance and explainability, endeavors such as this one pave the way for standardization of CTG analysis, ideally translating into better clinical outcomes in labor and delivery.Biomedical Engineering, Department ofHonors Colleg
Effectual Truth and the Machiavellian Enterprise
No full textThe political philosophy of Niccolò Machiavelli has often been reduced to the statement that ‘the end justifies the means’ and understood as an expression of realpolitik as a result of his pragmatic, even ruthless, counsel to would-be princes, or political leaders. However, a more nuanced understanding of Machiavelli’s reflections on human nature in his writings, especially The Prince, reveals that there is a philosophic core within his approach to political success, the acquisition and maintenance of state. But while there is no doubt that Machiavelli openly rejected the idealism of certain ancient and medieval thinkers, whose imagined republics only ever existed in theory, and instead candidly advised princes to seek and wield power, his work reflects not only a profound engagement with the harsh realities of a political landscape dominated by practical necessity but also a project of far-reaching scope. With the concept of “effectual truth” as his guide, Machiavelli proposes radical means to overcome fortuna with virtù and establish the foundations of power in order to bring about that conquest. The fulfillment of his mission and mandate to those who follow his lead represents the Machiavellian enterprise
Spatiotemporal Monitoring of the Effects of Climate Change on the Water Surface Area of Sidi Salem Dam, Northern Tunisia
No full textThis research presents a comprehensive spatiotemporal assessment of the effects of climate change and anthropogenic pressures on the water surface area and quality of the Sidi Salem Dam, the largest reservoir in Northern Tunisia. Located within a sub-humid to Mediterranean humid bioclimatic zone, the dam plays a vital role in regional water supply, irrigation, and flood control. Utilizing a 40-year dataset (1985–2025), this study integrates multi-temporal satellite imagery and geospatial analysis using Geographic Information System (GIS) and remote sensing (RS) techniques. The temporal variability of the dam’s surface water extent was monitored through indices such as the Normalized Difference Water Index (NDWI). The analysis was further supported by climate data, including records of precipitation, temperature, and evapotranspiration, to assess correlations with observed hydrological changes. The findings revealed a significant reduction in the dam’s surface area, from approximately 37.8 km2 in 1985 to 19.8 km2 in 2025, indicating a net loss of 18 km2 (47.6%). The Mann–Kendall trend test confirmed a significant long-term increase in annual precipitation, while annual temperature showed no significant trend. Nevertheless, recent observations indicate a decline in precipitation during the most recent period. Furthermore, Pearson correlation analysis revealed a significant negative relationship between precipitation and temperature, suggesting that wet years are generally associated with cooler conditions, whereas dry years coincide with warmer conditions. This hydroclimatic interplay underscores the complex dynamics driving reservoir fluctuations. Simultaneously, land use changes in the catchment area, particularly the expansion of agriculture, urban development, and deforestation have led to increased surface runoff and soil erosion, intensifying sediment deposition in the reservoir. This has progressively reduced the dam’s storage capacity, further diminishing its water storage efficiency. This study also investigates the degradation of water quality associated with declining water levels and climatic stress. Indicators such as turbidity and salinity were evaluated, showing clear signs of deterioration resulting from both natural and human-induced processes. Increased salinity and pollutant concentrations are primarily linked to reduced dilution capacity, intensified evaporation, and agrochemical runoff containing fertilizers and other contaminants
Role of RNA Regulator CELF1 in DNA Damage Repair
No full textMyotonic dystrophy type 1 (DM1), is a neuromuscular disease characterized by muscle weakness and myotonia, is caused by a trinucleotide repeat expansion in the DMPK gene; causing dysregulation of the RNA-binding protein CELF1. While CELF1's role in RNA processing is well-established in DM1 pathology, recent studies suggest its involvement in DNA damage repair, observed as increased sensitivity to etoposide (ETO) upon CELF1 knockout in cancer cells. This study aimed to investigate CELF1's role in DNA damage response in striated muscle cells. CRISPR-Cas9 gene editing was employed to generate CELF1 knockout in C2C12 and AC16 muscle cell lines using both 'indel' and 'deletion' strategies, targeting specific exons of the CELF1 gene. Successful transfection and knockout were confirmed through fluorescence microscopy, flow cytometry, PCR amplification, and Sanger sequencing. Preliminary PCR results confirmed successful gene deletion. Subsequent experiments will assess the sensitivity of CELF1 knockout muscle cells to ETO treatment, thereby elucidating the potential role of CELF1 in DNA damage repair within muscle tissue.Biology and Biochemistry, Department ofHonors Colleg
Maximizing Oil Recovery from a Steeply Dipping Reservoir Near a Salt Dome
No full textSalt diapirs trap many hydrocarbon accumulations that offer special challenges to exploration and development. The reservoir understudy is formed by two faults on the western and eastern side and a salt dome on the southern side. The reservoir is a thick sand body dipping at an angle of 35-40 degrees, with high permeability rocks, reservoir pressure closes to oil bubble point pressure and containing about 12 MMSTB. Three wells penetrate the reservoir with trajectories made complex by limitations on the surface wellhead location. These wells present special flow assurance challenges and are perhaps suboptimally located for maximizing oil recovery. To implement the right development plan, we built an accurate reservoir and well model that matches 17 months of production history from the existing wells and then used the reservoir model to evaluate different development scenarios considering various well management options, reservoir and fluid property uncertainties, and the introduction of an additional well. We used seismic data to build the static geological model, and formation evaluation logs, core analyses from nearby wells, and PVT analysis to build the dynamic reservoir flow model. We performed pressure transient analysis to identify reservoir features, boundaries, and how the rock properties change away from the wells. We built well models that honored essential trajectory and completion design features, then we exported vertical lift performance (VLP) curves from the matched well models to the reservoir model for accurate well modeling. KAPPA Rubis and Saphir software packages were used to build a numerical 3D reservoir model, and nodal analysis software was used to build the well models. The simulation shows that the combination of dipping reservoir, good rock quality, strong water drive, and well positions provided favorable conditions to obtain maximum recovery. The simulation also shows that the completion of the wells affects the recovery factor and the amount of water needed to be handled on the surface. This work investigates how best to manage the existing wells and the merits of completing the additional well to increase oil recovery from the limited reservoir volume. This work illustrates that commercial software can be used to efficiently resolve critical questions specific to relatively common conventional reservoir type occurring near salt domes. This approach may enable portfolio managers to recommend developing similar reservoirs that would otherwise rank below other development prospects
Latinos that Receive Physical Activity Counseling Are More Likely to Engage in Aerobic Physical Activity
No full textBackground: Latinos are more likely than non-Latino White adults to receive physical activity (PA) counseling. However, less is known about the association between PA counseling and aerobic PA in Latinos, and whether this association varies by sex. Methods: We used cross-sectional 2016-2017 National Health Interview Survey (NHIS) data on Latinos ≥18 years of age (n=6,853). Participants were asked if over the last year they had been told by a doctor or health professional to increase their PA ('PA counseling'). Aerobic PA was categorized as: 1) none: 0 minutes/week; 2) some: >0 min/week but less than guideline; 3) met guideline: ≥150 min of moderate-vigorous activity or ≥75 min of vigorous activity or 150 min of moderate activity/week. Covariate-adjusted multinomial logistic regression models estimated the association between PA counseling and aerobic PA, and were stratified by sex. Results: In adjusted models, compared with not receiving PA counseling, those that received PA counseling were significantly more likely to engage in some PA (adjusted Odds Ratio (aOR): 1.58; 95% Confidence Interval (CI): 1.17, 2.12). Stratified by sex, Latina women that received PA counseling were more likely to engage in some PA (aOR: 1.89; 95% CI: 1.35, 2.66) and meet the aerobic PA guideline (aOR: 1.36; 95% CI: 1.03, 1.78). Conclusion: PA counseling may help promote engagement in at least some aerobic PA in Latinos. Among Latinas, receiving PA counseling may encourage enough PA to meet the aerobic PA guideline. Future PA promotion efforts should consider the role of healthcare providers in PA among Latinos.Psychological, Health, and Learning Sciences, Department ofHonors Colleg