1,778 research outputs found

    Preparation for action: Psychophysiological activity preceding a motor skill as a function of expertise, performance outcome, and psychological pressure

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    Knowledge of the psychophysiological responses that characterize optimal motor performance is required to inform biofeedback interventions. This experiment compared cortical, cardiac, muscular, and kinematic activity in 10 experts and 10 novices as they performed golf putts in low- and high-pressure conditions. Results revealed that in the final seconds preceding movement, experts displayed a greater reduction in heart rate and EEG theta, high-alpha, and beta power, when compared to novices. EEG high-alpha power also predicted success, with participants producing less high-alpha power in the seconds preceding putts that were holed compared to those that were missed. Increased pressure had little impact on psychophysiological activity. It was concluded that greater reductions in EEG high-alpha power during preparation for action reflect more resources being devoted to response programming, and could underlie successful accuracy-based performance

    Introduction

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    What are the strategies, modalities and aspirations of island-based, stateless nationalist and regionalist parties in the twenty-first century? Political independence is now easier to achieve, even by the smallest of territories; yet, it is not so likely to be pursued with any vigour by the world's various persisting sub-national (and mainly island) jurisdictions. Theirs is a pursuit of different expressions of sub-national autonomy, stopping short of independence. And yet, a number of independence referenda are scheduled, including one looming in Scotland in autumn 2014

    Premovement high-alpha power is modulated by previous movement errors: Indirect evidence to endorse high-alpha power as a marker of resource allocation during motor programming

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    Previous electroencephalographic studies have identified premovement high-alpha power as a predictor of movement accuracy; less frontal-central high-alpha power is associated with accurate movements (e.g., holed golf putts), and could reflect more cognitive resources being allocated to response programming. The present experiment tested this interpretation. Ten expert and ten novice golfers completed 120 putts while high-alpha power was recorded and analyzed as a function of whether the previous putt was holed (i.e., a correct response) or missed (i.e., an error). Existing evidence indicates that more resources are allocated to response programming following errors. We observed less premovement high-alpha power following errors, especially in experts. Our findings provide indirect evidence that high-alpha power is an inverse marker of the amount of resources allocated to motor response programmin

    Effects of ingesting JavaFit Energy Extreme functional coffee on aerobic and anaerobic fitness markers in recreationally-active coffee consumers

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    The purpose of this study was to examine the effects of ingesting JavaFit™ Energy Extreme (JEE) on aerobic and anaerobic performance measures in recreationally-active male and female coffee drinkers. Five male (27.6 ± 4.2 yrs, 93.2 ± 11.7 kg, 181.6 ± 6.9 cm) and five female (29 ± 4.6 yrs, 61.5 ± 9.2 kg, 167.6 ± 6.9 cm) regular coffee drinkers (i.e., 223.9 ± 62.7 mg·d(-1 )of caffeine) participated in this study. In a cross-over, randomized design, participants performed a baseline (BASELINE) graded treadmill test (GXT) for peak VO(2 )assessment and a Wingate test for peak power. Approximately 3–4 d following BASELINE testing, participants returned to the lab for the first trial and ingested 354 ml of either JEE or decaffeinated coffee (DECAF), after which they performed a GXT and Wingate test. Criterion measures during the GXT included an assessment of peakVO(2 )at maximal exercise, as well as VO(2 )at 3 minutes and 10 minutes post-exercise. Additionally, time-to-exhaustion (TTE), maximal RPE, mean heart rate (HR), mean systolic pressure (SBP), and mean diastolic blood pressure (DBP) were measured during each condition. Criterion measures for the Wingate included mean HR, SBP, DBP, peak power, and time to peak power (TTP). Participants then returned to the lab approximately one week later to perform the second trial under the same conditions as the first, except consuming the remaining coffee. Data were analyzed using a one way ANOVA (p < 0.05). Our results indicate that JEE significantly increased VO(2 )at 3 minutes post-exercise when compared to BASELINE (p = 0.04) and DECAF (p = 0.02) values, which may be beneficial in enhancing post-exercise fat metabolism

    Genome-wide RNA sequencing of ocular fibroblasts from glaucomatous and normal eyes: Implications for glaucoma management

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    Primary open angle glaucoma is a leading cause of visual impairment and blindness which is commonly treated with drugs or laser but may require surgery. Tenon’s ocular fibroblasts are involved in wound-healing after glaucoma filtration surgery and may compromise a favourable outcome of glaucoma surgery by contributing to fibrosis. To investigate changes in gene expression and key pathways contributing to the glaucomatous state we performed genome-wide RNA sequencing. Human Tenon’s ocular fibroblasts were cultured from normal and glaucomatous human donors undergoing eye surgery (n = 12). mRNA was extracted and RNA-Seq performed on the Illumina platform. Differentially expressed genes were identified using a bioinformatics pipeline consisting of FastQC, STAR, FeatureCounts and edgeR. Changes in biological functions and pathways were determined using Enrichr and clustered using Cytoscape. A total of 5817 genes were differentially expressed between Tenon’s ocular fibroblasts from normal versus glaucomatous eyes. Enrichment analysis showed 787 significantly different biological functions and pathways which were clustered into 176 clusters. Tenon’s ocular fibroblasts from glaucomatous eyes showed signs of fibrosis with fibroblast to myofibroblast transdifferentiation and associated changes in mitochondrial fission, remodeling of the extracellular matrix, proliferation, unfolded protein response, inflammation and apoptosis which may relate to the pathogenesis of glaucoma or the detrimental effects of topical glaucoma therapies. Altered gene expression in glaucomatous Tenon’s ocular fibroblasts may contribute to an unfavourable outcome of glaucoma filtration surgery. This work presents a genome-wide transcriptome of glaucomatous versus normal Tenon’s ocular fibroblasts which may identify genes or pathways of therapeutic value to improve surgical outcomes

    Multi-vehicle Control in a Strong Flowfield with Application to Hurricane Sampling

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    A major obstacle to path-planning and formation-control algorithms in multi-vehicle systems are strong flows in which the ambient flow speed is greater than the vehicle speed relative to the flow. This challenge is espe-cially pertinent in the application of unmanned aircraft used for collecting targeted observations in a hurricane. The presence of such a flowfield may inhibit a vehicle from making forward progress relative to a ground-fixed frame, thus limiting the directions in which it can travel. Using a self-propelled particle model in which each particle moves at constant speed relative to the flow, this paper presents results for motion coordination in a strong, known flowfield. We present the particle model with respect to inertial and rotating reference frames and provide for each case a set of con-ditions on the flowfield that ensure trajectory feasibility. Results from the Lyapunov-based design of decentralized control algorithms are presented for circular, folium, and spirograph trajectories, which are selected for their potential use as hurricane sampling trajectories. The theoretical results are illustrated using numerical simulations in an idealized hurricane model. Nomenclature N Number of particles in the system k Particle index k = 1,..., N rk Position of k th particle with respect to inertial frame r̃k Position of k th particle with respect to rotating fram

    Cross-Country Transportation Efficacy and Clinical Outcomes of Preloaded Large-Diameter Ultra-Thin Descemet Stripping Automated Endothelial Keratoplasty Grafts

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    PURPOSE: To evaluate the clinical outcomes of preloaded large-diameter ultra-thin grafts for Descemet stripping automated endothelial keratoplasty (UT-DSAEK) after cross-country shipment. METHODS: A laboratory study in an eye bank and a clinical cohort study in an academic tertiary care center were performed. UT-DSAEK (9.5 mm diameter) grafts (n = 7) were prepared, loaded into a commercial device (iGlide; Eurobio, Les Ulis, France), preserved for 4 days at room temperature in transport medium, and analyzed. In a retrospective study, preloaded tissues (n = 39) for clinical use were prepared, transported from Italy to the United Kingdom, and surgically delivered into the eyes of patients undergoing UT-DSAEK. Central and peripheral endothelial cell density (ECD) and viability were measured before and after loading and storage of the grafts in the laboratory study. Clinically, best-corrected visual acuity, ECD before and at final follow-up, dislocation rate, primary graft failure, and surgical time were recorded. RESULTS: In the laboratory study, postcut central graft thickness was 93.3 ± 17.2 μm. ECD and cell mortality did not change significantly before and after preservation (P = 0.8). Cell loss after 4 days of preservation was 1.7% ± 1.6%. Clinically, 39 eyes of 39 patients at final follow-up showed a mean central graft thickness of 88 ± 22 μm and a best-corrected visual acuity of 0.34 ± 0.24 logMAR. Nine of 39 cases (23%) needed rebubbling, and 28% cell loss was observed at final follow-up. CONCLUSIONS: Large-diameter UT-DSAEK grafts can be prepared and preloaded in the eye bank using the iGlide and transported to the surgical center facilitating surgery for patients undergoing UT-DSAEK, potentially reducing tissue wastage, surgical time, and costs related to surgery

    Intellectual property management and technological entrepreneurship

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    This paper investigates the distinctive technology protection strategies of entrepreneurial technology firms. In contrast with much popular opinion, it is reported that intellectual property features more prominently in the business of small entrepreneurial firms than it does in the business of large, established mature firms. The intellectual property portfolios of technology firms of all sizes and ages exhibit a rich array of instruments in addition to patents for protecting technology, including trade secrets, trademarks and copyright, together with licenses to externally sourced technology. The intellectual property profiles of technology firms appear to be influenced by their context, organizational profiles and corporate goals and by the character of their technology

    Relationship between vascular resistance and sympathetic nerve fiber density in arterial vessels in children with sleep disordered breathing

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    Sleep disordered breathing in children is associated with increased blood flow velocity and sympathetic overactivity. Sympathetic overactivity results in peripheral vasoconstriction and reduced systemic vascular compliance, which increases blood flow velocity during systole. Augmented blood flow velocity is recognized to promote vascular remodeling. Importantly, increased vascular sympathetic nerve fiber density and innervation in early life plays a key role in the development of early-onset hypertension in animal models. Examination of sympathetic nerve fiber density of the tonsillar arteries in children undergoing adenotonsillectomy for Sleep disordered breathing will address this question in humans.Thirteen children scheduled for adenotonsillectomy to treat sleep disordered breathing underwent pupillometry, polysomnography, flow-mediated dilation, resting brachial artery blood flow velocity (velocity time integral), and platelet aggregation. The dorsal lingual artery (tonsil) was stained and immunofluorescence techniques used to determine sympathetic nerve fiber density. Sympathetic nerve fiber density was correlated with increased resting velocity time integral (r=0.63; P<0.05) and a lower Neuronal Pupillary Index (r=-0.71, P<0.01), as well as a slower mean pupillary constriction velocity (mean, r=-0.64; P<0.05). A faster resting velocity time integral was associated with a slower peak pupillary constriction velocity (r=-0.77; P<0.01) and higher platelet aggregation to collagen antigen (r=0.64; P<0.05). Slower mean and peak pupillary constriction velocity were associated with higher platelet aggregation scores (P<0.05; P<0.01, respectively).These results indicate that sympathetic activity is associated with change in both the function and structure of systemic vasculature in children with sleep disordered breathing.Anna Kontos, Kurt Lushington, James Martin, Quenten Schwarz, Ryan Green, Ben, David Wabnitz, Xiangjun Xu, Elke M. Sokoya, Scott Willoughby, Mathias Baumert, Antonio Ferrante, Melissa La Forgia, Declan Kenned
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