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Molecular Evolution in the Mountains: Genetic Affinity and the Environment led to Adaptive Variation in the American Pika (Ochotona princeps)
Get PDFThe American pika (Ochotona princeps) is discontinuously distributed in high elevation and montane regions across western North America, where isolated lineages have potentially evolved along divergent trajectories since the mid-Pleistocene. Ochotona princeps encounters cold temperatures, hypoxia, and dietary toxins, and therefore has thermoregulatory, metabolic, and behavioral adaptations related to these environmental challenges. Studies have confirmed interspecific adaptive variation between O. princeps and other Ochotona species, but there is limited research regarding intraspecific adaptive variation within O. princeps. I investigated adaptive responses in a panel of candidate genes with functions related to these conditions in Ochotona and other mammal species. I aimed to identify variation in genotype-environment associations across five O. princeps lineages and determine ancestries of these selective signals. I sequenced candidate genes in 179 Ochotona samples using custom hybridization baits. Resultant SNP datasets were tested for genotype-environment associations using redundancy analysis and latent factor mixed models. Significant outlier alleles were identified from relationships with elevation, temperature, and precipitation and varying ancestral relationships in key adaptive genes were determined. I argue that genetic affinity in O. princeps significantly interacts with landscape features, resulting in unique genotypes among genes related to environmental adaptation
Daily Activity Patterns Among Apex Predators in the Northwest United States
Get PDFThe gray wolf [Canis lupus], brown bear [Ursus arctos], and American black bear [Ursus americanus], are all ecologically interesting because they are all apex predators that exist in the same spaces in the United States. However, little research has been done after wolf reintroduction in many parts of the western U.S. to see if these three predators will change their daily activity patterns around each other. The goal of this research project was to see whether the daily activity patterns of the gray wolf, brown bear, and American black bear differ, and it was hypothesized that he American black bear and brown bear will be more active during the day while the gray wolf will be more active at night. Bar graphs of the daily activity pattern of each species was created using occurrences in camera trap images from Snapshot USA. Overall, the observed daily activity patterns show that the American black bear and brown bear followed a crepuscular activity pattern and the gray wolf followed a nocturnal activity pattern. Knowing these daily activity patterns can help mitigate human-wildlife conflict in spaces where they interact, which is especially important for the gray wolf since it is endangered, and future research could look into the cause of the activity patterns of the gray wolf, brown bear, and American black bear, whether it be due to competition among each other, with other species, or with humans
Raised In A Shockwave
No full textRAISED IN A SHOCKWAVE is a Young Adult Science Fiction novel centering around a young girl who joins a mutual aid organization focused on creating a network of community and support for a newly-birthed group of superhumans. The themes of the book include the importance of forming bonds across marginalized communities, the creation of the self as a self-made, joyful exercise in horror, and the deconstruction and examination of superhero stories as a genre. The book is preceded by an analysis of the DC Comics cartoon Static Shock, one of my chief influences for this project. This analysis is focused on the ways the show handles ideas around marginalization, inhuman bodies, and heroic infrastructure
Tarsal metric trends over the Medieval-Post-Medieval transition in London
Get PDFThe Medieval-Post-Medieval transition in England was an important shift in the human biocultural environment. With urbanization and industrialization came resultant changes in living and working conditions and subsequent effects on the skeleton. In addition, the Post-Medieval period ushered in changes in footwear and activity patterns, with potential consequences on foot bone morphology. The objective of this study is to compare calcaneal and talar lengths between the Medieval and Post-Medieval periods to determine whether there are quantifiable differences that correspond to shifting footwear and activity patterns. T-tests and ANCOVAs (and their non-parametric equivalents) were used to compare calcaneal and talar lengths of 1086 adults from 14 London cemeteries (Medieval n = 8, Post-Medieval n = 6), available in the Oracle Wellcome Osteological Research Database (WORD) curated by the Museum of London. Males and females were also analyzed separately. In the total sample, tali and calcanei are longer in the Medieval period (p \u3c 0.001 for both tarsals). When males and females are analyzed separately, male talar length is greater in the Post-Medieval period (p \u3c 0.001). The difference in talar length between periods is not statistically significant for females (p = 0.093). These differences in talar and calcaneal lengths between periods likely reflect differences in footwear between the Medieval and Post-Medieval periods. The magnitude of these differences varies according to sex, indicating that the change in footwear had differential impacts on men and women. Together, these results suggest that Medieval and Post-Medieval tarsals physically incorporated their respective cultural environments and gendered differences in cultural practice, particularly related to the footwear characteristic of each period
DEVELOPMENT OF A MEASUREMENT SYSTEM FOR THE EVALUATION OF KINEMATICS AND IMPACT FORCES IN HISTORICAL FENCING COMBAT
Get PDFThis study aims at evaluating the impact forces acting on the blades of swords during a combat. Such forces will be used as input for numerical simulations to estimate the sword durability. Some replicas of the 17th century swords were instrumented with strain gauges and inertial sensors were placed on athletes’ joints to reconstruct arm kinematic. The forces along the two relevant axes are calculated by linear regression of two Wheatstone bridges and results were consistent with previsions. The calibration showed small uncertainty (max 11 N) with the transverse sensitivity being directly included in calibration parameters. In addition, the system was fully synchronized between all its parts and the bandwidth seems sufficient to calculate the impacts
COMPARISON OF MARKER AND MARKERLESS MOTION CAPTURE SYSTEM FOR GAIT KINEMATICS
Get PDFThe purpose of this study was to compare gait kinematics measured with a markerless motion capture system against data measured with a marker-based motion capture system. A sample of 14 over-ground walking trials were captured simultaneously with two camcorders (60Hz) and an 8-camera marker system. The markerless data was further processed to landmarks using markerless human movement automatic capture system (FastMove). Body landmarks data of X and Z coordinates were highly consistent between the two systems, while data of Y coordinate showed low consistency. The Bland-Altman plots’ results showed low agreement between individual measurements of the maximum and minimum of knee and ankle flexion angles from both systems against the average of the measurement
HOW CRITICAL IS THE CHOICE OF DISTANCE-BASED MEASURES IN STUDYING TUMBLE TURN PERFORMANCE?
Get PDFThe turn is a crucial part of swim races and therefore requires systematic investigation. Yet, many different measures of turn performance are used in the literature. This study aimed to examine the level of agreement and the sensitivity of six fixed-distance based performance measures of the tumble turn. Tumble turn data of 10 Dutch elite level swimmers were analysed using those measures. The overall level of agreement was high between all measures (R ranging from 0.91 to 0.99). However, if the swimmers were ranked according to each of those measures, not all performance measures resulted in the same ranking. In particular, the rankings for measures with an exist distance of 10 m deviated from those for measures with an exit distance of 5 or 15 m. This finding suggests that the performance measures of interest are sensitive to different phases of the turn
CORRELATIONS OF POSTURAL CONTROL TO PROPRIOCEPTION, TACTILE SENSATION AND MUSCLE STRENGTH AMONG OLDER ADULTS
Get PDFBackground: Falls are one of the most important causes of physical injury and death in older adults. Postural control is associated with an elevated risk of falls in older adults. the purpose of this study was to assess the correlation between static/dynamic postural control ability and proprioception, plantar skin touch, and muscle strength in older adults.
Method: Partial correlation analysis was used to quantitatively analyze the correlation between plantar tactile sensitivity, proprioception, lower limb muscle strength and postural control, and regression analysis was used to build an effective model of human postural control.
Result: The postural control of the older adults is related to the plantar tactile sensitivity, proprioception, and lower limb muscle strength.
Conclusion: dynamic postural control mainly affected by lower limb muscle strength and proprioception, suggesting that trainings to improve the ankle plantarflexion, hip abduction muscle strength and knee and ankle proprioception should be recommended to older adults to improve dynamic postural control. Static postural control mainly affected by planter tactile sensitivity and proprioception suggesting that trainings to improve the proprioception and planter tactile sensitivity should be recommended to older adults to improve static postural control