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Subfitness in Distributive (Semi)lattices
Get PDFWe investigate whether the set of subfit elements of a distributive semilattice is an ideal. This question was raised by the second author at the BLAST conference in 2022. We show that in general it has a negative solution, however if the semilattice is a lattice, then the solution is positive. This is somewhat unexpected since, as we show, a semilattice is subfit if and only if so is its distributive lattice envelope
A Euclidean Proof for the Fourth Postulate
Get PDFWe discuss some classical conundrums about Euclid\u27s Fourth Postulate. Our inquire sheds lights on the role the postulate is playing within the deductive structure of Book I of the Elements and provides a proof of it fully admissible within Euclid\u27s original setting
Predicting Precipitation and NDVI Utilization of the Multi-level Linear Mixed-Effects Model and the CA-Markov Simulation Model
Get PDFThe current work intends to reconstruct the spatiotemporal evolution of precipitation and the Normalized Differentiate Vegetation Index (NDVI) in the Loukkos watershed and provide scenarios for their recent and future evolution, therefore determining the degree of association. We conducted a study on the time series data of precipitation and NDVI from 1999 to 2019. The NDVI prediction is conducted using the CA-Markov model and the linear mixed-effects multi-level model (LME) with precipitation data from 2019 to 2040. The CA-Markov model was employed to predict the vegetation indices for 2029 and 2040 using 1999, 2009, and 2019 data. The model simulates future precipitation estimates for up to 2040 using different daily precipitation data series obtained from ten meteorological stations between 1999 and 2019. The accuracy of NDVI simulation is evaluated using kappa indices, specifically location of 88%, 0 of 86%, and standard of 83%, indicating that the consistency between the simulated NDVI map of 2019 and the actual one is nearly perfect, indicating statistical reliability of our model. The precipitation forecast for the Loukkos watershed predicts that average annual precipitation will decrease by 11.4% between 1999 and 2040. In contrast, based on 2019, there will be an increase in low vegetation areas and a decline in dense regions in the eastern and western parts of the basin in 2029 (−12.89%) and 2040 (−12.78%), respectively. The findings of this study suggest that by 2040, the Loukkos watershed will be exposed to future climate hazards, such as reduced precipitation and vegetation. The integration of geoinformation and prediction models is a great resource for optimizing environmental planning to prepare and potentially mitigate the harmful effects of climate change and its consequences for both humanity and the environment
1st Place Contest Entry: Effectiveness of Intravesical BCG in the Treatment of Nonmuscle Invasive Bladder Cancer: An Umbrella Review
Get PDFThis is Gerald Obinna Ozota\u27s submission for the 2025 Eric M. Scandrett Graduate Research Prize, which won first place. It contains their essay on using library resources, their bibliography, and a summary of their research project on conducting a systematic literature search to identify all relevant systematic reviews and meta-analyses investigating the effectiveness of intravesical Bacillus Calmette-Guerin (BCG) on Non-muscle-invasive Bladder Cancer (NIMBC).
Gerald is a student in the Ph.D. in Pharmaceutical Sciences program at Chapman University. Their faculty mentor is Dr. Lawrence Brown
2nd Place Contest Entry: The Role of Repertoire Selection and Teacher Collaboration in Culturally Responsive Music Education
Get PDFThis is Robin Gomes, Connor Bogenreif, and Mir Aminy\u27s submission for the 2025 Eric M. Scandrett Graduate Research Prize, which won second place. It contains their essay on using library resources, their bibliography, and a summary of their research project on the role of repertoire selection and teacher collaboration in culturally responsive music education.
Robin, Connor, and Mir are doctoral students in the Ph.D. in Education program at Chapman University. Their faculty mentor are Dr. Howard and Dr. Havard
Indirect Genetic Effects Among Neighbors Promote Cooperation and Accelerate Adaptation in a Small-scale Human Society
Get PDFExplaining the rapid evolution of human cooperation and its role in our species’ biodemographic success remains a major evolutionary puzzle. To address this challenge, we tested a social drive hypothesis, which predicts that social plasticity and social selection in human groups cause indirect genetic effects that accelerate the adaptation of fitness, promoting population growth via feedback between the environmental causes and evolutionary consequences of cooperation. Using Bayesian multilevel models to analyze fertility data from a small-scale society, we demonstrate that density- and frequency-dependent indirect genetic effects on fitness promote the evolution of cooperation among neighboring women, increasing the rate of contemporary adaptation by ~5×. Our results show how interactions between the genetic and socioecological processes shaping cooperation in reproduction can drive rapid growth and social evolution in human populations
Energy Expenditure and Obesity Across the Economic Spectrum
Get PDFGlobal economic development has been associated with an increased prevalence of obesity and related health problems. Increased caloric intake and reduced energy expenditure are both cited as development-related contributors to the obesity crisis, but their relative importance remains unresolved. Here, we examine energy expenditure and two measures of obesity (body fat percentage and body mass index, BMI) for 4,213 adults from 34 populations across six continents and a wide range of lifestyles and economies, including hunter-gatherer, pastoralist, farming, and industrialized populations. Economic development was positively associated with greater body mass, BMI, and body fat, but also with greater total, basal, and activity energy expenditure. Body size–adjusted total and basal energy expenditures both decreased approximately 6 to 11% with increasing economic development, but were highly variable among populations and did not correspond closely with lifestyle. Body size–adjusted total energy expenditure was negatively, but weakly, associated with measures of obesity, accounting for roughly one-tenth of the elevated body fat percentage and BMI associated with economic development. In contrast, estimated energy intake was greater in economically developed populations, and in populations with available data (n = 25), the percentage of ultraprocessed food in the diet was associated with body fat percentage, suggesting that dietary intake plays a far greater role than reduced energy expenditure in obesity related to economic development
Multitasking While Walking: How Green Noise and Texting Alter Gait
Get PDFThis study examines the combined effects of green noise and texting on gait to understand how multitasking and auditory stimuli affect walking stability. Green noise, associated with relaxation, was the environmental stimulus; texting the cognitive distractor. We hypothesized texting would reduce cadence and stride length, with green noise either stabilizing or disrupting gait. Ten participants walked on a treadmill under five conditions: normal walking (NW), no texting/sound (WNTNS), sound only (WNTS), texting only (WTNS), and texting with sound (WTS). Gait parameters—step length, step width, single support time, and terminal double support time—were analyzed. Step length decreased in WNTS (p = .0106) and WTS (p = .0115) versus NW; step width increased in WTNS (p \u3c .0001). Single support time was prolonged in WTS; terminal double support time increased in all conditions vs. NW (p = .0435). Cognitive and environmental distractions alter gait, potentially increasing fall risk. Further research should explore how green noise and texting influence walking stability
Limited Soil Water Recharge in Summer Affects Seasonal Isotopic Signatures of Tree Xylem Water
No full textRecent studies have reported that xylem waters in forest trees during the summer growing season are often isotopically similar to winter, rather than summer, precipitation. Several hypotheses have been proposed to explain this observation, which can be viewed as a form of ecohydrological separation, but empirical tests spanning space and time remain limited. We hypothesise that variations in the seasonal origin of precipitation found in tree xylem waters can be explained by seasonal differences in soil water recharge. We test this hypothesis by evaluating to what extent climatic aridity can explain seasonal signals in extensive surveys of the isotope ratios of tree xylem waters across Switzerland. Using these tree xylem stable water isotope data from previous studies, we show that (i) there is only limited summer precipitation replenishing soil water storage in places where evaporative demand in summer is high and that (ii) seasonal differences in PET/P can broadly predict the seasonality of soil water recharge and tree water uptake of spruce and beech trees
Inflammation and Detection: Rethinking the Biomarker Landscape in Gastric Cancer
Get PDFGastric carcinoma is a leading cause of cancer-related mortality worldwide, yet reliable noninvasive biomarkers for its early detection remain limited. As research continues to elucidate the inflammatory underpinnings of tumor initiation and progression, it has become increasingly clear that pro-inflammatory cytokines may hold promise as diagnostic adjuncts. Serum cytokines such as interleukin (IL)-1β, IL-6, IL-8, and interferon-gamma have been frequently reported as elevated in gastric cancer patients compared to healthy individuals. These molecules, known for their roles in modulating tumor-promoting inflammation, angiogenesis, and immune evasion, may serve as accessible indicators of disease presence or progression. Several studies have shown that individual cytokines, particularly IL-6 and IL-8, can achieve receiver operating characteristic curves and area under the curve values exceeding 0.70, suggesting reasonable diagnostic utility. We assess the comparative utility of individual cytokines versus multiplex panels, evaluate their roles in tumor biology and treatment resistance, and situate these findings within the broader inflammatory biomarker landscape. Limitations of the current literature, including small sample sizes, heterogeneity in study design, and lack of specificity, are critically discussed. We advocate for prospective, multicenter validation studies and highlight the promise of integrating inflammatory cytokine profiling into diagnostic algorithms. Composite cytokine panels may better reflect the complex immunobiology of tumor progression and offer a scalable, accessible adjunct to current gastric cancer screening strategies