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Editorial for the Special Issue of Journal of Risk and Financial Management: Featured Papers in Mathematics and Finance
No full textWe are privileged to present this Special Issue of the Journal of Risk and Financial Management (JRFM), focused on the intersection of mathematics and finance. The 27 contributions to this issue explore theoretical advancements and practical applications in financial risk management, asset pricing, and portfolio optimization. These papers collectively emphasize the ongoing synergy between mathematical rigor and financial innovation
Characterizing the physicochemical properties of magnetic nanoparticles by a surface plasmon resonance approach
No full textMagnetic nanoparticles (MNPs) are widely recognized as effective signal amplifiers for surface plasmon resonance (SPR)-based biosensors. Herein, we report that SPR sensors can be a useful tool to characterize the physicochemical properties of surface-functionalized iron oxide MNPs. In this work, a Kretschmann configuration-based SPR sensing platform with a scanning angular range of up to 17° is employed to identify the resonance conditions of different MNP suspensions. We demonstrate the feasibility of SPR for differentiating different surface coatings on the iron oxide MNPs, such as amine, biotin, and streptavidin, as well as distinguishing different magnetic core sizes (from 15 nm to 30 nm) and nanoparticle concentrations (from 0.013 mg/ml to 2.5 mg/ml). The SPR resonance angle shift, Δθ, is used as a crucial parameter for characterizing these physicochemical properties of MNPs floating within the surface of the metal layer that can directly interact with the surface plasmons, and the variation of their physicochemical properties is the reason causing a shift in the SPR resonance angle
SWCPC 438 Negatives #49 A. E. Flowers, undated.
No full textThe collection features portraits of sixty-one prominent cattle ranchers, both male and female, who were considered to be the “Cattle Kings of Texas.
SWCPC 438 #58 R. B. Masterson, undated.
No full textThe collection features portraits of sixty-one prominent cattle ranchers, both male and female, who were considered to be the “Cattle Kings of Texas.
Effects of biopolymers, cork, and Rhizobium tropici-derived extracellular polymeric substances on soil microbial communities
No full textIntroduction: Soil microorganisms play a crucial role in plant development, while biopolymers, such as cork and Extracellular Polymeric Substances/Exopolysaccharides (EPS), can enhance soil health. However, these amendments may affect DNA extraction and microbial analysis, necessitating the validation of the extraction method before conducting next-generation sequencing (NGS).
Methods: This study evaluated 48 soil samples from Decatur, Alabama (Silt loam) that underwent four treatments: unamended soil (soil.control), soil with cork (soil.cork), soil with EPS (soil.EPS), and soil with both cork and EPS (soil.cork.EPS). Samples were collected at four time intervals (0-, 24-, 48-, and 72-hours post-treatment), with three biological replicates for each treatment. The FastDNA Spin Kit proved the most effective among the six DNA extraction methods tested.
Results and discussion: Amplicon sequencing of the 16S rRNA gene identified 62,996 amplicon sequence variants (ASVs), with 513 ASVs shared across all time points and 467 ASVs shared among the different treatments. The microbial community was primarily composed of Actinobacteria, Proteobacteria, and Acidobacteria, with Actinobacteria being the most abundant phylum. Actinobacteria, Alphaproteobacteria, Bacilli, and Betaproteobacteria contributed to microbial diversity at the class level. Notable families such as Bacillaceae, Gaiellaceae, Micromonosporaceae, and Streptomycetaceae showed treatment-dependent variations. Core microbiome analysis revealed Bacillus and Gaiella as the dominant genera, which play vital roles in soil ecosystem stability and nutrient cycling. These microbes contribute to carbon sequestration, nitrogen fixation, and phosphorus solubilization, improving soil fertility and plant-microbe interactions. These findings offer valuable insights into microbial dynamics in amended soils, providing information that can improve soil quality and agricultural productivity.The author(s) declare financial support was received for the research and/or publication of this article. This work is supported by the United States Department of Defense/Cooperative Agreement # W912HZ-20-2-0064-Laboratory Investigation of Biologically Strengthening Military Earthen Structures Grant, Capacity Building (#2020-38821-31103) and Evans Allen (#7005717/ALAX- 011-1223EA) Grants from the U.S. Department of Agriculture’s National Institute of Food and Agriculture. These funds have been utilized in the study’s design, data collection, analysis, interpretation, writing, and manuscript submission
Infectious Disease Dynamics in Heterogeneous Populations: Stochastic, Seasonal, and Structured Epidemic Models with Intervention Strategies
No full textInfectious diseases continue to pose a significant threat to public health worldwide, shaped by complex interactions among environmental, biological, and social factors. Among these, seasonality plays a major role in driving the timing and scale of recurring outbreaks in numerous diseases including influenza, malaria, dengue, cholera, respiratory syncytial virus, norovirus, Lyme disease, and others. To address the challenges of modeling seasonal infectious diseases, we develop and analyze a set of stochastic epidemic models that account for environmental and demographic variability. Each stochastic epidemic model is represented as a continuous-time Markov chain (CTMC) derived from an underlying ordinary differential equation (ODE) framework. Using a branching process approximation of the Markov chain, we estimate seasonal probabilities of disease extinction by varying a wide range of periodic parameters, including transmission, recovery, dispersal, and vector population dynamics. Emphasis is placed on the roles of the exposed and infectious stages, as well as phase shifts relative to the seasonal drivers. Several essential epidemiological outcome measures are consolidated and extended to more complex stochastic settings to facilitate comparisons of extinction dynamics in seasonal versus constant environments. This includes the introduction of a new measure that provides useful predictions about the probabilities of extinction in both settings. In addition, we examine the timing and effectiveness of periodic vector control intervention, and present an age-structured malaria model to explore the synergistic effects of treatment and vaccination strategies. The numerical analysis provides new insights, revealing that disease emergence is shaped by the magnitudes, relative amplitudes, and synchrony of seasonal parameters, highlighting the need for targeted, integrated, and well-timed intervention strategies. These findings demonstrate how mathematical models can bridge theory and practice by offering useful tools to simulate, predict, and inform the design of effective public health interventions
Parent and caregiver preferences for eHealth programs
No full textBackground
Online programs serve as an important avenue for delivering mental health and parenting services worldwide. The quantity of online programs proliferated during the COVID-19 pandemic with developers emphasizing the potential to improve accessibility and reduce barriers of in-person programming (e.g., arranging transportation, childcare, and scheduling). However, Canadian parents’ and caregivers’ preferences for features they desire in online family mental health supports are unknown. Understanding these preferences would better allow for the creation of programs that are best suited to meet parents’ needs. Thus, the present study examined parent mental health program preferences, barriers to access, and how different sociodemographic factors predicted preferences for aspects such as program features (e.g., duration delivery format).
Methods
Self-report surveys were administered in 2023 via the online crowdsourcing platform AskingCanadians to parents and primary caregivers of children ages 0 to 5 years. Descriptive statistics examined parent mental health program preferences and barriers. Regression models examined sociodemographic predictors of these preferences and barriers.
Results
Participants identified a range of preferences across program structure and coaching, as well as challenges associated with program access. Parents most preferred programs with a web-based delivery format (72%), a duration of 2–4 weeks (27%), and psychologists as program coaches (51.4%). The most highly endorsed barriers were lack of time (42.2%) and limited internet access (25.1%). Sociodemographic factors including parent gender, household income, education, and ethnicity also consistently predicted preference for various program characteristics.
Conclusions
This research provides an important first step toward creating more accessible online mental health and parent mental health programs by ensuring the voices of the parents who will use these services are heard in program development and adaptation. Future research should investigate how to address accessibility and inclusivity barriers to participating in parent mental health programs for diverse families based on their differential preferences
Natural Curiosity: Investigating how nature interactions influence informal STEAM learning during preschool age
No full textEarly childhood is a critical period for STEAM (Science, Technology, Engineering, Arts, and Mathematics) learning, as children naturally exhibit curiosity, exploration, and problem-solving behaviors during this stage. Informal STEAM learning, particularly in outdoor settings, can significantly influence children's cognitive development and long-term academic success. The natural environment provides a rich context for experiential learning, aligning with the principles of Experiential Learning Theory (ELT), which emphasizes the importance of direct, hands-on experiences in fostering scientific thinking and understanding. However, very few studies have discussed how nature-based outdoor learning landscapes influence the STEAM concept formation of children and which physical factors of an outdoor landscape impact childhood learning. To address these questions, this research adopted a Combined Research Design with a combination of Qualitative Content Analysis, Case Study Research and Evidence-Based Design Interventions. In the first phase, a scoping review examined the impact of nature-based outdoor learning environments on the formation of STEAM concepts in preschoolers. A systematic review documented existing assessment tools for childcare outdoor environments, revealing a pressing need for systematic assessment tools to evaluate outdoor STEAM learning affordances. The second phase utilized a nature-based preschool in Texas as a case study to establish that an outdoor learning environment designed with appropriate landscape elements/play settings is associated with increased occurrences of STEAM-related behaviors and learning activities. The final phase introduced an evidence-based playground design to investigate how children's engagement in informal STEAM learning activities changes before and after the intervention at a preschool playground in Texas. The findings underscore the critical role of landscape design in promoting STEAM learning experiences for young children in an outdoor play and learning environment
Understanding the Impact of the Farm and Lairage Environments on Salmonella Contamination in Market Hogs
No full textSalmonella contamination in pork products presents a major public health risk.
Lymphatic tissues (nodes) can become incorporated into non-intact products such as ground pork posing a greater Salmonella risk. This study evaluated Salmonella prevalence and quantification across the pork production chain, including on-farm, transport, lairage, and lymph node samples, through four swine flows (n = 250 samples per flow). Detection and enumeration were performed using the BAX®-System-SalQuant®, with results expressed as Log₁₀ CFU+1/sample to include non-detectable samples. Finishing pen swabs (n=10 per flow) showed prevalence of 20% (Flow 1), 0% (Flow 2), and 60% for both Flows 3 and 4. Pre-transport trailer samples (n=3 per flow) were positive in Flow 1 (66.6%), Flow 2 (100.0%), and Flows 3 and 4 (33.3%). Post-transport trailer samples were 100% positive across all flows. All quantification results for farm and trailer samples were below the limit of quantification (LOQ). Lairage pen socks from study (n=6 per flow) and non-study (n=18 per flow) pens showed widespread contamination. Study pens had 100% prevalence in all flows, with quantification ranging from 0.25 to 2.08 Log CFU+1/sample. Non-study pens reached up to 2.55 Log CFU+1/sample. Lymph node contamination varied significantly by type. Superficial inguinal lymph nodes (n=105 per flow) had a low overall prevalence (7.1%) and mean count of 0.016 Log CFU+1/sample. Mesenteric lymph nodes (n=105 per flow) showed higher prevalence (31.7%) and quantification (0.43 Log CFU+1/sample), with a maximum near 5 Log CFU+1/sample. Flow 2 had the highest mesenteric 32 contamination (57.1%, 1.06 Log CFU+1/sample). Significant differences were observed between node types and among flows (p < 0.05). These findings highlight transport, lairage, and mesenteric lymph nodes as critical contamination points. Future research should incorporate serotyping and seasonal analysis to support targeted Salmonella control strategies in pork production
An Eccentric Sub-Neptune Moving Into the Evaporation Desert
No full textThough missions such as Kepler, K2, and TESS have discovered >2000 sub-Neptune and Neptunian planets, there is a dearth of such planets at close-in (P ≲ 3 days) orbits. This feature, called the Neptune desert or the evaporation desert, is believed to be primarily shaped by planetary migration and photoevaporation. However, this region is not completely devoid of planets—a small number of very hot Neptunes reside within the desert. These planets provide an opportunity to directly probe the effects of migration and photoevaporation. We present confirmation of TOI-5800 b, an eccentric sub-Neptune on an ≈2.6 day period that is likely actively undergoing tidal migration. We use radial velocity measurements from the Carnegie Planet Finder Spectrograph to constrain TOI-5800 b’s mass and eccentricity. We find that it has an unusually high eccentricity (0.39 ± 0.07) for its short orbit. TOI-5800 b is therefore currently experiencing high levels of tidal heating as it moves into the desert. Ranked as a top candidate for transmission and emission spectroscopy within its temperature and radius regime, TOI-5800 b is a prime target for atmospheric characterization with the James Webb Space Telescope. TOI-5800 b presents a unique opportunity to study the atmosphere of a planet undergoing tidal heating and to probe the composition of sub-Neptune planets.This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under grant No. 1745302. The work of H.P.O., M.L., and D.E. has been carried out within the framework of the NCCR Planets supported by the Swiss National Science Foundation under grants 51NF40_182901 and 51NF40_205606. D.E. and M.L. acknowledge funding support from the Swiss National Science Foundation projects 200021_200726 (D.E.) and PCEFP2_194576 (M.L.). C.B. acknowledges support from the Swiss Space Office through the ESA PRODEX program. T.G.W. acknowledges support from the UKSA and the University of Warwick. T.D. acknowledges support from the McDonnell Center for the Space Sciences at Washington University in St. Louis