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The development of an IMU based measurement system for the determination of the subtalar joint axis
Get PDFThe subtalar joint axis influences biomechanical variables, especially regarding the lower limbs. The purpose of this study was to develop a measurement system for the subtalar joint axis based on inertial measurement units. Different development steps were taken, like an axis estimation algorithm using a principal component analysis and multiple approaches for the reference of the subtalar joint axis to the anatomical coordinate system. In the current development step, we try to solve the reference problem by using fused IMU data to track the offset to the foots longitudinal axis. As of now it is possible to determine the axis with a range of 4° for the inclination and 7° for the deviation within 5 measurements. Although, this approach leaves room for improvement, it could already be an acceptable method for large-scale studies and an easy-to-use alternative to imaging methods
THE GRIP PRESSURE ANALYSIS OF THREE BADMINTON FOREHAND OVERHEAD STROKES – A CASE STUDY
Get PDFThe purpose of this study was to analyze the palm distribution variables (finger forces and pressure) on the dominant hand of a collegiate 1st class female badminton player when performing drop, clear, and smash overhead strokes. We aimed to analyze from the preparation period to the contact point with the shuttle. A high-speed digital camera (2000Hz) and a grip measurement system (500Hz) were simultaneously used to record the 2D movement and collect 18 palm areas of grip force and pressure of the dominant hand. The results showed that the finger signal of the forehand overhead strokes of the participant was similar for both clear and smash strokes. The peak grip pressure of the movements appeared before the contact point in all three different overhead strokes. Based on the results, we suggest that increasing grip strength training might enhance shuttle velocity
IDENTIFICATION OF POTENTIAL BIOMECHANICAL RISK FACTORS FOR RUNNING OVERUSE INJURIES FROM A PROSPECTIVE 4HAIE STUDY – PILOT ANALYSES
Get PDFThe study aimed to identify potential biomechanical risk factors associated with the incidence of running overuse injuries. A total of 747 runners aged 18-65 participated in the study. Runners underwent running biomechanics at a self-selected speed. Subsequently, each runner underwent a one-year follow-up period, during which runners reported running overuse injuries through a weekly online questionnaire. Spatiotemporal distances and biomechanical variables of the right lower limb were analysed. Biomechanical variables were associated with the incidence of running overuse injuries using binary multivariable logistic regression. The incidence of running injuries after one year of observation was 28.9%. Incidence of running overuse injuries was associated, for example, with step width, step frequency, and range of motion of the knee joint from IC to maximum adduction
TRICEPS SURAE MUSCLE FORCES DURING WALKING AND DANCING ACROSS VARIED FOOTWEAR
Get PDFDespite a high prevalence for Achilles tendinopathies in athletic populations, research on individuality in muscle coordination, a possible contributor to this disorder, is limited. Effects of shoe condition and kinematics on force share between triceps surea muscles during normal gait and a dance step were investigated and compared between two methodological approaches. Muscle coordination was analyzed based on musculoskeletal simulations in a generic and an electromyography-informed approach. The electromyography-informed mode revealed higher individuality and a higher force production in medial gastrocnemius for the dance step in high heels compared to bare foot. The study underscores the importance of viewing Achilles tendon loads from an individual’s perspective and recommends personalized musculoskeletal simulations for studies on muscle coordination
CLASSIFICATION OF HEALTHY LIMB LOADING DURING RUNNING IN POST ANTERIOR CRUCIATE LIGAMENT INDIVIDUALS
Get PDFThe purpose of this study was to identify and evaluate the effectiveness of new gait metrics to dynamically assess healthy limb performance in post anterior cruciate ligament reconstruction (ACLR) individuals. Metrics comparing the active-to-impact peaks (AIP) ratio and late-to-mid knee flexion angle (LMKF) ratio were extracted from the vertical ground reaction force and knee flexion angle waveforms, respectively, to identify healthy limb loading dynamics during running. One variable binary logistic model was used to model healthy limb loading based on the AIP and LMKF metrics. The metrics successfully aided in the delineation between healthy and pathological movement dynamics. These findings are important because it identifies new metrics that are not dependent on the performance of the individuals non-reconstructed limb to quantify their reconstructed limb function
USING ADDITIONAL MEASURES OF HANDGRIP STRENGTH TO PREDICT AEROBIC CAPACITY IN WHEELCHAIR USERS
Get PDFManual wheelchair users have been shown to have low physical capacity and impaired ability to perform activities of daily living. Current tests and protocols for assessing physical capacity in wheelchair users have specific boundaries. Measuring handgrip strength (HGS) with electronic handgrip dynamometers has been shown to be a reliable measure of muscle function and a convenient assessment of overall muscle strength. This study aimed to determine the correlation of maximal HGS, HGS rate of force development, HGS fatigability, HGS isometric control, and HGS asymmetry to a six-minute wheelchair propulsion (6MPT) test in ambulatory young adults. Thirty-four recreationally active ambulatory individuals aged 23.76±3.57yrs participated in this study. HGS was assessed using electronic handgrip dynamometry. Aerobic capacity was assessed using the 6MPT. Handgrip fatigability showed significant near moderate negative correlation (r=-0.345, p0.05) were also shown between handgrip rate of force development, fatigue, isometric control and asymmetry respectively. Our findings that additional measures of HGS were correlated with aerobic capacity in ambulatory adults may suggest measures of HGS could be predictive of aerobic capacity in those who use manual wheelchairs. Additional research is necessary to further understand these relationships
Who’s Next: Elementary Principals’ Process for Identifying Future School Leaders in Washtenaw County, Michigan
Get PDFThis qualitative study investigated how six experienced elementary school principals in Washtenaw County identify internal candidates for future principal positions, aiming to enhance understanding of educational leadership and succession planning. The research addresses two primary questions: (1) How do principals identify prospective internal candidates for school leadership? and (2) What competencies or characteristics do principals use to determine candidates\u27 suitability for school leadership? Three themes emerged for the first question: informal recognition of leadership potential through daily interactions; providing leadership opportunities such as leading committees or mentoring teachers; and engaging in direct conversations about career goals. For the second question, five themes emerged: instructional leadership, where candidates demonstrated a deep understanding of curriculum, instruction, and assessment; personal influence, characterized by self-confidence, integrity, and the ability to inspire others; relationship building, with an emphasis on maintaining strong relationships with staff, students, parents, and the community; resilience and adaptability in handling the complexities of school leadership; and decision making, with the ability to make sound decisions under pressure. The study underscores the crucial role of school principals in identifying and nurturing potential school leaders from within their schools. The identified competencies align closely with established educational leadership standards, suggesting that a strategic and systematic approach to leadership identification and development can ensure a strong pipeline of effective leaders prepared to drive positive change in schools
Case Study on Seney National Wildlife Refuge: How the Upper Peninsula Led Wildlife Conservation in the Beginning of the Twentieth Century
Get PDFThe research presented in this paper will weave together the story of how the Upper Peninsula became a crucial hub for wildlife conservation in the first half of the twentieth century. Seeking to answer the question of how and why this occurred, as well as why it is distinct from the social movement of the 1960s, the research is based on public awareness, photographic research developments, and the concept of the national system for conservation. Hunting played the main role in the motivations for this movement therefore, it is also heavily discussed throughout. The previous research on this subject emerged as a result of the social movement in the later twentieth century or came from an earlier conception of the process through which environmental conditions shape human activity. This research uses those frameworks to analyze how important figures and concepts led to an earlier conservation movement which has not been as heavily circulated in academia. The research contributes to the valuable history of the Upper Peninsula, its impacts on national movements and the experiences of those who worked or lived here during the early twentieth century
FROM TURF TO TURF: FUNGAL INVASION OF ASCOCORYNE TURFICOLA IN A NORTHERN MICHIGAN BOG
Get PDFThis is the first paper to report Ascocoryne turficola Boud. 1905 (Helotiales: Ascomycota) within the United States. It is an obligate bog fungus native to Europe and Siberia, where it is extremely rare across most of its range. A. turficola appeared at Lily Pond Bog in Marquette, Michigan (87.47º W, 46.59º N) in 2019, almost contemporaneous with anecdotal reports in Minnesota and Ontario. Since 2019, the Lily Pond population has exploded and become the dominant fungus in this bog but has yet to spread to similar bogs nearby. This species is adapted to long distance dispersal and carries the potential to continue spreading. Using a combined approach of NMDS ordination and a case-controlled, binomial logistic repression, I modeled the vegetation and environmental variables associated with A. turficola. The strongest plant indicators were Rhynchospora alba and Eriophorum virginicum. Although not indicator species, ericaceous shrubs were present in 100% of plots with A. turifcola, suggesting a possible ericoid mycorrhizal relationship (ERM), which is especially common among fungi in the Helotiales. A. turficola occurrence also peaked at a pH of 4.3, and declined sharply at higher and lower pH. The associated vegetation, preference for intermediate pH and bare peat close to the water table—all demonstrate that A. turficola prefers “hollows” or “hollow edges” rather than more acidic sphagnum hummocks. ITS barcode sequencing and BLAST analysis showed a 99.9% genetic match to samples from Scotland. Here I discuss a single species but hope to highlight phenomena that are more common than previously thought
Magpy: A Python Package for Magmas
Get PDFThere exist a multitude of computational tools available to mathematicians, such as interactive and automated theorem provers, finite counter-example generators, and computer algebra systems, most of which have a complicated installation process, unintuitive syntax, a lack of comprehensiveness for mathematical structures, or some combination of these. Computer algebra systems are indispensable tools due to their capacity for creating mathematical objects and performing computations on them. However, there is a lack of computational resources that focus on dealing with explicit examples, and extracting the properties thereof, especially for the most basic algebraic structures. Here, we will dive into several prominent computer algebra systems and their capabilities, and isolate some of the unfortunate mechanics or other assets of these systems. Afterwards, we will traverse a novel computer algebra system with a primary focus on manipulation and property extraction of the most basic algebraic structures. This system aims to serve mathematicians with little programming experience by keeping the syntax simple and intuitive, extensible, and easy to learn