5954 research outputs found
Sort by
TASK CONSTRAINTS MODIFY INTRISIC HEAD-TRUNK DYNAMICS DURING RUNNING AND SIDESTEPPING
Get PDFThe purpose of this study was to examine head movement control during running and sidestepping tasks. Fourteen collegiate male athletes performed running and sidestepping tasks. Sagittal and transverse head and trunk angles, vertical trunk displacement and head-trunk coordination were assessed during the flight and stance phases. The sidestepping task resulted in greater transverse and sagittal plane head and trunk range of motion. During stance, transverse plane head-trunk coordination was more in-phase, with reduced vertical trunk-sagittal head anti-phase coordination during sidestepping tasks. During sidestepping tasks, visual field reorientation required greater contributions from the head in the transverse plane, but with reduced sagittal plane compensation, reduced perceptual awareness may be observed, with negative implications on sport performance and injury risk
Linking Art and Science to Catalyze Creative Thinking and Scientific Inquiry
No full textA bourgeoning body of literature indicates that visual arts can connect people to science by appealing to the affective domain of learning (i.e., attitude, emotion, engagement) rather than engaging the cognitive domain (i.e., application, comprehension, understanding) that is typically emphasized in science education. In fact, evidence suggests that art-based science communication catalyzes creativity and discovery thereby promoting intuitive thinking. Thus, my goal is synergize art and science through accurate scientific illustration to make wildlife microbial ecology more accessible to the general public and inspire people to consider the relationships between mammals and their microbes. To achieve my goal, I am collaborating with the Wildlife Ecology and Conservation Science Lab at NMU to create accurate, fine-scale natural history illustrations of mammals, the environments in which they live, and their gastrointestinal tracts in order to highlight the diverse micro-ecosystems that occur within the mammalian body. By synergizing art and science, I hope to inspire the general public to think more deeply about the interrelatedness of mammals and their microbes and to learn and grow their knowledge of the world around them
Detection of the Human Necrobiome in Soil: A Pilot Study
No full textForensic microbiology has gained recognition in recent years for its utility in postmortem interval (PMI) estimation. I conducted my research at the NMU Forensic Research Outdoor Station (FROST), one of 10 facilities in North America dedicated to research involving human taphonomy (the study of all factors that affect the body after death). The main purpose of this research is to explore relationships between the necrobiome (bacteria and other microbes associated with human remains) and the soil microbiome. Two guiding research questions are: 1. Is the human necrobiome detectable in soil surrounding a decomposing body? and 2. Does the concentration of the human necrobiome in the soil change with time and distance? To answer these questions, soil samples were systematically collected on three separate dates from an area surrounding a human donor at FROST. Samples were collected from the surface and from 10cm below the surface using a soil probe. Control samples were also collected and analyzed for comparative purposes. Bacterial DNA was extracted and isolated from each soil sample using the DNeasy Powersoil Kit from Qiagen. After bacterial 16S sequencing of the
samples at Michigan State University, bioinformatics analysis sorted the DNA sequences into the appropriate bacterial classifications (phyla, classes, orders, families, and genuses). Results show which bacteria are present and in what relative concentrations. These concentrations and the spatial and temporal analyses could have applications in medicolegal death investigations and PMI estimation. Knowing how long a body has been in a location may help investigators identify victims and/or possible suspects
Activity pattern variation of three canine species in Michigan’s Upper Peninsula
No full textThe coyote (Canis latrans), the gray wolf (Canis lupus), and the red fox (Vulpes vulpes) are all known to be ecologically significant predators. All three are widely known canine species ranging in size, but also share similarities due to their close taxonomic relationship. Yet, they have many notable differences as a result of adapting to different drivers of speciation, such as competition or food source availability. Further, it is my goal to determine if there are differences in their daily activity patterns which have previously been observed as crepuscular. Data used for my research was collected using camera traps from the Snapshot USA project located in the Upper Peninsula of Michigan. By running a chi square test, I determined that coyotes are nocturnal, however, the red fox and gray wolf are indeterminant, or cathemeral. Studying daily activity patterns is vital to understanding a species ecological role and impact on their environment. Further research could determine how species activity patterns have impacted various wildlife populations and communities, as well as potential ecological drivers and disturbances that have caused these activity patterns
Hidden Diversity of Madagascan Freshwater Crabs (Brachyura: Potamoidea) Revealed by Morphological and Molecular Studies
No full textThis study focuses on the freshwater crab fauna of the island of Madagascar. Relatively little is known about the species diversity of the island’s freshwater crabs and their phylogenetic relationships. Chapter 1 is based on a newly published molecular phylogeny that used the highest taxonomic sampling to date, including almost all of the island’s known freshwater crab genera and species. The phylogeny revealed a significant number of unidentified specimens that belong to several new lineages that potentially represent as many as 4 new genera and 10 new species. Chapters 2 and 3 focus on the taxonomic revision of the genus Foza, which was found to be polyphyletic because its four assigned species were positioned on three separate lineages within the tree. Chapter 4 reconstructs ancestral character states by mapping morphological characters onto the molecular phylogeny of the Malagasy freshwater crabs to better understand character evolution in these crabs. Character states of the mandibular palp, the ambulatory legs, and the gonopods were mapped onto the molecular phylogeny for all 24 species of Malagasy freshwater crabs. Patterns were interpreted in the context of monophyletic groups on the tree. The results indicated that the early ancestors of the Malagasy freshwater crabs likely had a mandibular palp with a medium sized anterior lobe, short ambulatory legs, and a first gonopod with a medium length terminal article that tapered to a pointed tip. Unusually long ambulatory legs belong to three different genera in unrelated lineages. This trait appears to be the result of convergent evolution
THE RELATIONSHIP BETWEEN ANGULAR MOMENTUM OF THE LOWER TRUNK AND SHOULDER JOINT FORCES DURING AN OVERARM THROW
Get PDFThe proximal-to-distal force transfer of the kinetic chain in overarm throwing has well-established movements. The nature of the transfer of momentum from the lower trunk to the shoulder during an overarm throw remains to be determined. This study explored correlations between angular momentum about the superior-inferior axis of the lower trunk and compressive and anterior shear forces at the shoulder in experienced baseball players as they made maximum effort throws from the outfield. We found no association between the maximum lower trunk angular momentum during the arm cocking phase and shoulder joint anterior shear force at ball release (r = 0.149, p = 0.244, 95% CI [0.165, 0.133]) or shoulder joint compressive force at ball release (r = 0.222, p = 0.149, 95% CI [0.226, 0.218]). Even experienced athletes may be inefficient at transferring momentum
HOW DOES LOWER EXTREMITY COORDINATION CHANGE BASED ON HEIGHT AND PHASE OF THE COUNTERMOVEMENT JUMP?
Get PDFWhile jumping is a fundamental movement skill, its coordination, especially at submaximal heights, is understudied. The purpose of this study was to use ground reaction force and 3D motion capture to understand how participants’ (n = 16, age = 23.0 ± 3.60 years) coordination patterns change when performing countermovement jumps to multiple heights (25%, 50%, 75%, 100%) across three phases of the jump (unweighting, eccentric, concentric) using modified vector coding. With increasing jump heights, anti-phase coordination of the thigh-pelvis segment couple in the unweighting phase increased (F = 17.05, p \u3c 0.001), while thigh-leading coordination decreased (F = 17.06, p \u3c 0.001). This finding, along with multiple significant coordination pattern changes in the eccentric phase of the jump, creates a framework for improved performance cueing and rehabilitation
TENNIS ONE-HANDED BACKHAND STROKE AT DIFFERENT IMPACT HEIGHTS
Get PDFThe purpose of this study was to compare the kinematic differences of the racket during a one-handed backhand stroke at different impact heights. Five male collegiate tennis players were instructed to stroke the incoming balls from different heights to a crosscourt target area. The impact heights were classified as High, Middle, and Low. Significant differences were observed at 3 heights for racket angles (p \u3c 0.05). The decrease of the angular velocity of upper trunk right-lateral rotation at High might be the main element that resulted in a decrease in the resultant velocity of the racket at impact. The greater moment of inertia of the dominant arm and racket about shoulder horizontal abduction-adduction axis at High made arm difficult to be accelerated. It might influence the velocity and control of the one-handed backhand stroke at high impact point
DIFFERENCES IN MAXIMAL STRENGTH CAPACITY BETWEEN ISOMETRIC SQUAT AND MID-THIGH PULL TESTS IN ELITE TRACK AND FIELD ATHLETES.
Get PDFThe aim of this study was to compare the vertical peak force (PF) generated during the isometric mid-thigh pull (IMTP) and isometric squat (ISqT) performed at the same knee and hip angles. Fourteen elite track and field athletes performed 3 maximal efforts of isometric IMTP and ISqT tests. The vertical PF was measured by a force platform (Kistler 9290CD, AG Winterthur, Switzerland). Our findings revealed significant higher PF and relative PF during ISqT than IMTP (Mean difference: 953 ± 224 N, p \u3c 0.001, d = 1.62 and 14.6 ± 2.4 N.kg-1, p \u3c 0.001, d = 3.8, respectively). The results of this study suggest that ISqT may be more appropriate testing procedure for identifying athletes’ maximum isometric strength capacities in elite track and field athletes
Daily Activity Patterns of Michigan Forest Squirrels
No full textThe eastern gray squirrel [Sciurus carolinensis], eastern fox squirrel [Sciurus niger], and American red squirrel [Tamiasciurus hudsonicus] all inhabit the boreal forests of Michigan and share a direct relationship as competitors for the same resources. The food-hoarding behavior of these species due to their competition aids in forest regeneration and seed dispersal. The goal of this study is to evaluate and compare the daily activity patterns of three these species to determine if their activity patterns differ from one another. It is hypothesized that the daily activity patterns of these species will not differ. Data for this study was gathered from Snapshot USA’s tree-mounted motion detecting camera traps which were deployed from September 2019 to October 2019, each collecting 400 camera nights of effort. They are positioned 0.5 meters off the ground, 200 meters from other cameras, in regular orientation (facing north,) and without bait. A chi square test was used to determine whether the three species display activity that is significant to any of three activity pattern categories or if the null hypothesis, stating that the data is not significant to any category, should be accepted and thus the species is cathemeral. The resulting p value of \u3c 0.0005 for all three species demonstrates that the data is significant to an activity pattern category and the null hypothesis is rejected. Histograms created from the gathered data suggest that all three squirrel species have diurnal tendencies and there is no significant difference between their activity patterns. Measuring and comparing the daily activity patterns of the eastern gray squirrel, eastern fox squirrel, and American red squirrel is important for better understanding how these species relate to one another, the composition of forests due to their competitive food-hoarding behaviors, and the ecological and evolutionary factors that drive these squirrels’ behavior