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MOLECULAR AND MORPHOLOGICAL CONSEQUENCES OF POST-GLACIAL CONTACT AMONG LINEAGES OF NORTHERN SHORT-TAILED SHREWS (Blarina brevicauda) IN EASTERN NORTH AMERICA
No full textDuring the Pleistocene, advancing glacial ice fragmented populations of species, which restricted populations from expanding, ultimately inhibiting gene flow. As glaciers receded, expansion out of unglaciated-isolated areas was possible. In addition to glacial barriers, landscape features such as rivers and mountain ranges served as barriers to dispersal of populations during the Pleistocene, influencing the phylogeography of multiple species. Though divergence between multiple lineages is a common feature of North American mammal diversity, circumstances that affected the post-glacial expansion of structured diversity within regions are less well-documented. Northern short-tailed shrews (Blarina brevicauda) are restricted to eastern North America, yet they exhibit three different mitochondrial lineages that diverged when historical populations retracted and became isolated from one another. In this study, I investigated the history of post-glacial expansion in historically isolated phylogroups of B. brevicauda, and interactions between these phylogroups across the contact zones where they meet. Using a genetic and morphological approach, I evaluated evidence for hybridization between historically isolated phylogroups of B. brevicauda by quantifying the distribution of genetic and morphological variation within and across contact zones. Individuals representing the Western phylogroup are larger than those of other lineages. In the Upper Peninsula of Michigan, where geographic overlap between adjacent B. brevicauda lineages is extensive, individuals that represent the Western genetic lineage are morphologically more similar to East-Central lineage individuals, indicating that genetic introgression between lineages is probable
Impression, Storm
No full textThis novel, set in a cypress swamp near Charleston, South Carolina, explores issues in gender, sexuality, the body, and place. An experiment in form, the novel is structured to replicate the passing of a hurricane over land. This model allows the narrative to expand its scope to encompass the swamp as a larger entity amidst the ecosystem of the coastal south. By weaving together the narratives of the plant, animal, human, ghost, and mythic members of the swamp, the narrative seeks to interrogate the ways that these different levels of an ecosystem intercede upon, assist, and redirect each other in known and unknown ways. Drawing on queer theory, environmental literature, southern studies, fine art criticism, and feminist scholarship, Impression, Storm takes a multidisciplinary approach to the art of storytelling. The scope of the narrative follows not only the imminent arrival and aftermath of a hurricane on the cypress swamp but also the dissolution of a friendship between the two central characters: Camille and Moon. These overlapping plots make for fresh readings of Sapphic love, gender relations, coming-of-age in the American South, and the mass changes affecting the environment through suburbanization
The Sound a Body Makes : and Other Ruminations on Navigating Roadkill
No full textUsing poetry, creative non-fiction, and watercolor paintings, this thesis interrogates my personal relationship with roadkill, as well as society’s relationship with roadkill. The lens of the collection is hyper-focused on roads, the treatment / beliefs surrounding roadkill, and the treatment of more-than-human bodies. Combining image and text, the reader is immersed in a unique conversation about our environment. The Sound a Body Makes utilizes a variety of poetic forms, as well as essay forms. Altogether, the collection is a call to action for radical change regarding how society views and treats more-than-human bodies
EFFECTS OF KINEMATIC FEEDBACK ON VERTICAL JUMP PERFORMANCE
Get PDFThe purpose of this study was to examine the immediate effects of kinematic feedback on vertical jump performance. Twenty recreationally active women were randomly assigned to the treatment or control group. Participants performed five maximal countermovement jumps pre-feedback and five jumps post-feedback. Visual and verbal feedback based on the mover’s pre-feedback jumps was provided to the treatment group. All participants were also allowed to view their jump performance on video. Treatment participants made reductions in maximal knee flexion (p=0.003) and depth of descent (p=0.003) but no significant changes in jump height (p=0.07), pre- to post-feedback. These findings suggest kinematic feedback is an effective means of modifying movement, however, the feedback in the present study did not result in improvement in jump height
COMPARISONS OF PRE-LANDING AND EARLY LANDING KNEE FLEXION ANGLES BETWEEN SEXES AND LANDING TASKS
Get PDFThe purpose was to compare pre-landing and early landing knee biomechanics between males and females and between double-leg and single-leg landings. Sixteen males and sixteen females participated in this study. The single-leg landings generally resulted in less time to minimal knee flexion angles prior to initial landing, decreased minimal knee flexion angles and average knee flexion velocities prior to initial landing, knee flexion angles at initial landing. The sex difference was only observed for knee flexion angles 50ms after initial landing in single-leg landings. These differences in the timing of minimal flexion angle and minimal knee angle prior to landing might be related to a small knee flexion angle at initial contact. Preparing for landing with greater knee flexion help mitigate the ACL injury risk in single-leg landings and women
REAL-TIME HAPTIC FEEDBACK SYSTEM VALIDITY AND ITS FESIBILITY FOR RUNNERS IN A REAL-WORLD TRAINING ENVIRONMENT
Get PDFThis study sought to assess the use of a novel integrated haptic feedback system for use during running; specifically, the study aimed to 1) assess the validity of the system in measuring trunk inclination and step rate during running and 2) assess the feasibility of the system to modify running technique in a real-world training environment. Ten recreational runners initially ran on an instrumented treadmill in a laboratory where trunk angle and step rate data were collected from an IMU-based system and compared against 3D motion capture and instrumented treadmill data. Participants then completed three outdoor training sessions using the haptic system to modify step rate. The haptic system was found to be valid when compared to gold-standard laboratory methods for measuring step rate (max 1.1% difference). It was also found to be feasible and intuitive in providing real-time feedback via a vibrating wrist-mounted unit in a real-world training environment. Overall, the system showed promise for application to real-world gait retraining, however further refinements are needed to improve the validity of trunk inclination measurements
CONTINUOUS CHANGES IN LEG STIFFNESS USING A MASS-SPRING-DAMPER MODEL WITH AN ACTUATOR DURING THE STEP PHASE OF THE TRIPLE JUMP
Get PDFThe purpose of this study was to examine a calculation method of the leg stiffness using the simplified leg model for evaluating the continuous changes in leg stiffness during the step phase of the triple jump. The leg stiffness is the ratio of the ground reaction forces to a displacement of the simplified leg length. We compared the difference in the leg stiffness between the previous method and the proposed method in this study. There was a non-linear and exponential relationship between the displacement of the simplified leg length and the elastic force. The peak value of leg stiffness calculated by the previous method was larger than that by the mass-spring-damper model with an actuator of the proposed method in this study. The previous method could overestimate the leg stiffness during the triple jump. The leg stiffness of the proposed method has a potential for representing the muscle-tendon behaviors during the triple jump
FRACTAL ANALYSES OF GAIT VARIABILITY DURING A MARATHON
Get PDFDetrended fluctuation analysis (DFA) and Higuchi’s fractal dimension (HG) have previously been used to characterise motor control during gait. However, there is limited evidence of either being applied to running gait within a race environment. The aims were to: i) examine statistical persistence and fractal dimension of stride dynamics during a marathon, and ii) explore the relationship between DFA and HG for running gait. Therefore, DFA and HG were applied to stride interval series of each km of the 2018 TCS New York Marathon. Results showed consistent persistence, variability, and fractal dimension of stride interval series throughout the marathon with no significant differences observed between the beginning, middle, and end of the Marathon. Moreover, HG was shown to correlate strongly with DFA, which may be useful in monitoring motor control using fractal analyses in real time, by decreasing computation time and improving robustness to changing time series lengths
CHARACTERISTICS OF THREE LOWER LIMB JOINT KIMETICS DURING THE REBOUND JUMP IN FEMALE ATHLETES
Get PDFThe aim of this study was to describe the lower limb muscle strength and power exertion characteristics of female athletes during the rebound jump (RJ) test. Forty-eight female soccer and basketball players performed the test, while the Quick Motion Analysis System was used to calculate joint kinetics (torque, power, and work of the three lower limb joints) in real time with high precision. A high correlation was found between the RJ index and contact time, jump height. In addition, a low correlation was found between jump height and contact time. However, the mechanical variables related to contact time and jump height were different. Therefore, for female athletes, the ability to shorten the contact time and the ability to obtain a jump height are considered independent abilities
LOOK MUMMY, NO HANDS! THE EFFECT OF TRUNK MOTION ON FORWARD WHEELCHAIR PROPULSION
Get PDFWheelchair and trunk-mounted IMUs provide a powerful and easy to use method for measuring wheelchair mobility performance. Yet, to develop more specific outcome measures, additional equipment can aid in gaining more insight. A new pushrim hit detection (RhIDE) method was used to investigate forward propulsion measured by frame acceleration in push and recovery phase. Four subjects sprinted at different intensities, while wheelchair velocity, acceleration, trunk movement and push phases were measured. Results show that 25-30% of the total forward propulsion per push (61 to 91 N∙s) was performed after hand release. This explorative study shows the significance of propulsion due to trunk movement in the recovery phase. Future research with this measurement setup and daily wheelchair users could help unravel the true share of trunk motion in forward propulsion, and its timing