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Monitoring in Ingleborough Show Cave (N. Yorkshire, UK) reveals the inf luence of tourism and cave management techniques on different parameters of the cave atmosphere. Exploratory aerosol monitoring identif ied a 0.015 ± 0.03 mg/m3 (≈70%) reduction in airborne particulates within the f irst 75 meters of cave passage and two major aerosol sources within this artif icially ventilated show cave. Autogenic aerosol production was identif ied close to active stream ways (increases of

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (body mass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use.

Newton's laws are used to study the effects of air resistance on an object's motion. In ball-related sports such as baseball, soccer, etc., understanding the effects of air resistance is essential to optimize ball launch performance. This performance optimization can be studied by identifying the minimal time it takes for a ball with speed v to travel a certain distance. We work with two models that apply to an object's motion. One of the models assumes a linear air drag while a second model makes use of a quadratic air drag. We do investigate known differential equations for when the Magnus force is present as well as absent. This is done through numerical and analytic solutions, when possible. The development of approximations leads to differential equations that are suitable for time optimization studies The analytic calculations are compared to MATLAB's numerical results. We concentrate on situations for which the speed of the projectile parallel to the ground is much greater than its speed perpendicular to it. Keywords: Mechanics, speed, sports, motion, air drag, INTRODUCTION The use of technology in sports allows for a deeper understanding of the physics of a sport, leading to increased knowledge and skill of play. In ball-related sports, such [...]

Remembering Antonia Teixeira: A Story of Missions, Violence, and Institutional Hypocrisy. By Mikeal C. Parsons and Joao B. Chaves. Grand Rapids, MI: William B. Eerdmans Publishing Company, 2023. 224 pp. [...]

The current study details changes in first-year international undergraduate students' perceived knowledge of, confidence in, and usefulness of intercultural skills in specific US university contexts after completing a semester-long academic and cultural transition course at a mid-sized private university. Results revealed significant increases in participants' (n = 42) perceived intercultural competence, perspective shifting, suspending judgment, self-advocacy, and interacting in class with students of other cultures; participants also reported significantly higher campus belonging and social support than a comparison group of students at the university who were not enrolled in the course (n = 32). These findings provide initial evidence for the potential of transition courses to increase intercultural skills and campus belonging for first-year undergraduate international students attending US universities.

Breathing mild bouts of low oxygen air (i.e. acute intermittent hypoxia, AIH) has been shown to improve locomotor function in humans after a spinal cord injury. How AIH‐induced gains in motor performance are achieved remains unclear. We examined the hypothesis that AIH augments motor learning and motor retention during a locomotor adaptation task. We further hypothesized that gains in motor learning and retention will be associated with reductions in net metabolic power, consistent with the acquisition of energetically favourable mechanics. Thirty healthy individuals were randomly allocated into either a control group or an AIH group. We utilized a split‐belt treadmill to characterize adaptations to an unexpected belt speed perturbation of equal magnitude during an initial exposure and a second exposure. Adaptation was characterized by changes in spatiotemporal step asymmetry, anterior–posterior force asymmetry, and net metabolic power. While both groups adapted by reducing spatial asymmetry, only the AIH group achieved significant reductions in double support time asymmetry and propulsive force asymmetry during both the initial and the second exposures to the belt speed perturbation. Net metabolic power was also significantly lower in the AIH group, with significant reductions from the initial perturbation exposure to the second. These results provide the first evidence that AIH mediates improvements in both motor learning and retention. Further, our results suggest that reductions in net metabolic power continue to be optimized upon subsequent learning and are driven by more energetically favourable temporal coordination strategies. Our observation that AIH facilitates motor learning and retention can be leveraged to design rehabilitation interventions that promote functional recovery. Key points: Brief exposures to low oxygen air, known as acute intermittent hypoxia (AIH), improves locomotor function in humans after a spinal cord injury, but it remains unclear how gains in motor performance are achieved.In this study, we tested the hypothesis that AIH induces enhancements in motor learning and retention by quantifying changes in interlimb coordination, anterior–posterior force symmetry and metabolic cost during a locomotor adaptation task.We show the first evidence that AIH improves both motor learning and savings of newly learned temporal interlimb coordination strategies and force asymmetry compared to untreated individuals.We further demonstrate that AIH elicits greater reductions in metabolic cost during motor learning that continues to be optimized upon subsequent learning.Our findings suggest that AIH‐induced gains in locomotor performance are facilitated by enhancements in motor learning and retention of more energetically favourable coordination strategies. [ABSTRACT FROM AUTHOR]