221 research outputs found

    Long-term effects of habitat clustering on spotted owl populations

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    A mass that has no (EBUS) echo.

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    We report findings for a patient that underwent endobronchial ultrasound (EBUS) guided transbronchial needle aspiration (TBNA) for diagnostic purposes after an abnormal chest CT. The patient initially presented with cough and shortness of breath. Chest CT revealed a 6 cm soft tissue mass with mildly enlarged right hilar lymph nodes (LNs) and a small right sided pleural effusion. Based on these radiologic findings, the patient underwent an EBUS guided FNA of the mass. To our surprise, the mass was hypoechoic by EBUS and on aspiration, the syringe filled with yellow fluid. This finding in combination with a re-review of the CT scans with a special focus on the Hounsfield Units of the lesion confirmed the diagnosis of a mediastinal bronchogenic cyst. This case demonstrates the role of Hounsfield units in analyzing mediastinal masses and highlights the effectiveness of EBUS guided TBNA in diagnosis and treatment of bronchogenic cysts

    An Investigation of Lower-extremity Functional Asymmetry For Non-preferred Able-bodied Walking Speeds

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    Functional asymmetry is an idea that is often used to explain documented bilateral asymmetries during able-bodied gait. Within this context, this idea suggests that the non-dominant and dominant legs, considered as whole entities, contribute asymmetrically to support and propulsion during walking. The degree of functional asymmetry may depend upon walking speed. The purpose of this study was to better understand a potential relationship between functional asymmetry and walking speed. We measured bilateral ground reaction forces (GRF) for 20 healthy subjects who walked at nine different speeds: preferred, +10%, +20%, +30%, +40%, -10%, -20%, -30%, and -40%. Contribution to support was determined to be the support impulse: the time integral of vertical GRF during stance. Contribution to propulsion was determined to be the propulsion impulse: the time integral of the anterior-posterior GRF, while this force was directed forward. Repeated measures ANOVA (α = 0.05) revealed leg × speed interactions for normalized support (p = 0.001) and propulsion (p = 0.001) impulses, indicating that speed does affect the degree of functional asymmetry during gait. Post hoc comparisons (α = 0.05) showed that support impulse was approximately 2% greater for the dominant leg, relative to the non-dominant leg, for the -10%, -20%, and -40% speeds. Propulsion impulse was 12% greater for the dominant leg than for the non-dominant leg at the +20% speed. Speed does appear to affect the magnitude of bilateral asymmetry during walking, however, only the bilateral difference for propulsion impulse at one fast speed (+20%) supported the functional asymmetry idea

    Variations in running technique between female sprinters, middle, and distance runners

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    International Journal of Exercise Science 6(1) : 43-51, 2013. In the sport of track and field, runners excel not only due to physiological characteristics but also aspects in running technique. Optimal technique allows runners the perfect the balance between running speed and economy. The ideal movement pattern may vary between events as the goal goes from economy of movement in the long-distance events to speed and power in the sprints. Understanding how each type of runner moves differently will help coaches more effectively train their athletes for each specific running event. This study was conducted to determine if sprinters, middle-distance, and long-distance runners would exhibit differences in form while running at the same speeds. Thirty female Division I collegiate runners participated in this study. Runners were separated into categories based on the events for which they were currently training in: 10 sprinters, 10 middle-distance, and 10 long-distance runners. Participants were asked to run twenty-two steps at five selected speeds. Knee angles, ground contact time, center of mass separation, and stride length were measured using a Vicon Nexus motion analysis system. Data was processed using analysis of variance and a Tukey post hoc analysis. Significant differences (p \u3c .05) occurred between long-distance runners and the other two groups (middle-distance and sprinters) for knee range, ground contact time, center of mass separation, and stride length at all five speeds. While running at the same speeds, there are specific characteristics of technique that distinguish long-distance runners from middle-distance and sprinters

    Ground Reaction Forces Generated by Twenty-eight Hatha Yoga Postures

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    Int J Exerc Sci 5(2) : 114-126, 2012. Adherents claim many benefits from the practice of yoga, including promotion of bone health and prevention of osteoporosis. However, no known studies have investigated whether yoga enhances bone mineral density. Furthermore, none have estimated reaction forces applied by yoga practitioners. The purpose of this study was to collect ground reaction force (GRF) data on a variety of hatha yoga postures that would commonly be practiced in fitness centers or private studios. Twelve female and eight male volunteers performed a sequence of 28 hatha yoga postures while GRF data were collected with an AMTI strain-gauge force platform. The sequence was repeated six times by each study subject. Four dependent variables were studied: peak vertical GRF, mean vertical GRF, peak resultant GRF, and mean resultant GRF. Univariate analysis was used to identify mean values and standard deviations for the dependent variables. Peak vertical and resultant values of each posture were similar for all subjects, and standard deviations were small. Similarly, mean vertical and resultant values were similar for all subjects. This 28 posture yoga sequence produced low impact GRF applied to upper and lower extremities. Further research is warranted to determine whether these forces are sufficient to promote osteogenesis or maintain current bone health in yoga practitioners

    Does Experimental Anterior Knee Pain Alter Effects of Running on Femoral Articular Cartilage Thickness and Volume? A Pilot Study

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    Anterior knee pain is a common problem for runners that often alters running biomechanics. It is unclear how/if changes in running biomechanics due to anterior knee pain affect knee articular cartilage health. PURPOSE: To determine if experimental anterior knee pain during running acutely alters deformation in femoral articular cartilage due to running. METHODS: 10 runners completed three sessions that each in- volved a 60-min treadmill run: a control, sham, and pain session. Experimental anterior knee pain was in- duced during the pain session via a continuous infusion of hypertonic saline into the infrapatellar fat pad. The sham and control sessions involved a continuous infusion of physiological saline and no infusion, re- spectively. Before and after running, magnetic resonance imaging was used to quantify femoral articular cartilage thickness and volume. A repeated measures ANOVA was used to evaluate effects of running with experimental anterior knee pain on perceived knee pain and femoral articular cartilage deformation (α = 0.05). RESULTS: Perceived anterior knee pain was significantly greater during the pain session relative to the control and sham sessions (p p = 0.05), and more due to the pain session run (-57.7 ± 157.4 mm3) than the control session run (p = 0.09). No significant effects of session were observed for medial or lateral thickness or lateral volume. CONCLUSION: Articular cartilage response to running (medial femoral volume) was different for the pain and sham sessions relative to the control session. The physiological and hypertonic saline infusions appeared to alter medial knee articular cartilage response to running. These changes might be due to altered biomechanics due to the infusions. Additional research is needed to clarify the cause of the altered response to running

    Subcellular organization of UBE3A in human cerebral cortex.

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    BackgroundLoss of UBE3A causes Angelman syndrome, whereas excess UBE3A activity appears to increase the risk for autism. Despite this powerful association with neurodevelopmental disorders, there is still much to be learned about UBE3A, including its cellular and subcellular organization in the human brain. The issue is important, since UBE3A's localization is integral to its function.MethodsWe used light and electron microscopic immunohistochemistry to study the cellular and subcellular distribution of UBE3A in the adult human cerebral cortex. Experiments were performed on multiple tissue sources, but our results focused on optimally preserved material, using surgically resected human temporal cortex of high ultrastructural quality from nine individuals.ResultsWe demonstrate that UBE3A is expressed in both glutamatergic and GABAergic neurons, and to a lesser extent in glial cells. We find that UBE3A in neurons has a non-uniform subcellular distribution. In somata, UBE3A preferentially concentrates in euchromatin-rich domains within the nucleus. Electron microscopy reveals that labeling concentrates in the head and neck of dendritic spines and is excluded from the PSD. Strongest labeling within the neuropil was found in axon terminals.ConclusionsBy highlighting the subcellular compartments in which UBE3A is likely to function in the human neocortex, our data provide insight into the diverse functional capacities of this E3 ligase. These anatomical data may help to elucidate the role of UBE3A in Angelman syndrome and autism spectrum disorder
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