892 research outputs found

    Transitional Activities in Elite Football: Frequency, Type, Effect on Match Outcome and the Novel Concept of Clusters

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    The aims of this study were to analyze the effect of contextual variables on physical metrics during transitions and investigate repeated transitional activities during transitions. Data was collected from 10 matches (23 elite soccer players). A total of 4249 individual observations were recorded including 1164 positive transitions (defense-to-attack), 1269 negative transitions (attack-to-defense), 1120 fast attacks, and 696 high pressure activities. Metrics per minute (m·min-1) as well as absolute variables: Total Distance (TD), high-speed running distance (HSRD, >19.8km·h-1), sprint distance (SD, >25.2km·h-1), relative high-speed running distance (VelB4), relative sprint distance (VelB5), acceleration distance (AccB3 Dist., distance with variations in running speed >3m·s-2), the number of high-intensity accelerations (HI Acc, >3m·s-2) and decelerations (HI Dec, >3m·s-2) were quantified. Significant effects of match half were found for TD (p <.001; ES =.03), HSRD (p = .023; ES = .012), VelB4 (p < .001; ES = .04), and HI Dec (p = .037; ES = .010). Match outcome had a relation to TD (m), HSRD (m) (p < .001), SD (m) and VelB4 (m) (p = .011) as well as VelB5 (m), and AccB3 Dist. distance (m) (p = .002 and p = .020, respectively). Performance in lost matches was lower in the 2nd half (p≤0.05). This study indicates that players are exposed to repeated short and intermittent high velocity actions together, highlighting the need to move away from 90min averages and pay more attention to transitional activities in modern training design

    Physical match demands across different playing positions during transitional play and high-pressure activities in elite soccer.

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    This study explored physical match demands across different playing positions during transitional play, to inform the need for position-specific training interventions. Data was collected using 10 Hz GPS units from 10 competitive matches including 23 elite soccer players of the 1st Polish Division (Ekstraklasa) in season 2020–21. A total of 4249 positional observations were made; center backs (n = 884), full backs (n = 972), central defensive midfielders (n = 236), central attacking midfielders (n = 270), central midfielders (n = 578), wingers (n = 778), and attackers (n = 531). Match data reflected distances covered per minute (m·min−1): total distance (TD), high-speed running distance (HSRD, > 19.8 km·h⁻¹), sprint distance (SD, > 25.2 km·h⁻¹), and the frequency of high-intensity accelerations and decelerations (A+D, > 3 m·s⁻²; n·min⁻¹). Total absolute sprint distance (SD, > 25.2 km·h⁻¹) and total relative sprint distance (Rel B5) were also quantified. A univariate analysis of variance revealed position-specific differences. Significant effects of position were found for all analysed metrics during transitional play (large ESs; p < .001). Central attacking midfielders displayed higher TD (m·min⁻¹), fullbacks covered highest SD (m·min⁻¹) and wingers achieved the highest A+D (n ·min⁻¹) (p ≤ 0.05). Centre backs displayed the lowest physical outputs when compared to all other positions, except in A+D (n ·min⁻¹) during defensive transitions (p ≤ 0.05). Attackers displayed the highest physical metrics during high pressure activities (p ≤ 0.05). Coaches should carefully consider positional transitional demands to better inform training design. With specific attention paid to drills that replicate game play

    Immunohistochemical characterization of feline lymphoplasmacytic anterior uveitis

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    OBJECTIVE: To characterize the immune cells present in different forms of feline anterior uveitis. SAMPLES: Eyes were obtained from 49 cats diagnosed with chronic idiopathic lymphoplasmacytic anterior uveitis, 7 cats with feline infectious peritonitis (FIP), and 9 cats euthanized for nonocular disease. METHODS: H&E sections were scored on the level of infiltrate in the anterior uvea. Immunohistochemistry was performed for FoxP3, CD3, and IL-17A, and positive cells were quantified in multiple images of each sample. A generalized estimating equation tested for an association between the level of inflammation and the prevalence of these cell types. RESULTS: Cells stained positive for IL-17A in idiopathic uveitis but not in FIP samples. We found significantly fewer FoxP3+and CD3+cells in low-grade compared with high-grade inflammation in idiopathic uveitis or FIP samples (P values all <.005), but no difference between FIP and high-grade samples. CONCLUSIONS: Idiopathic, but not FIP-associated, uveitis appears to have Th17 cell involvement. The numbers of FoxP3+and CD3+T-cells present appear directly correlated; thus, the severity of disease does not appear directly determined by the numbers of regulatory cells

    Strategies to prevent Clostridium difficile infections in acute care hospitals: 2014 update

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    Previously published guidelines are available that provide comprehensive recommendations for detecting and preventing healthcare-associated infections (HAIs). The intent of this document is to highlight practical recommendations in a concise format designed to assist acute care hospitals in implementing and prioritizing their Clostridium difficile infection (CDI) prevention efforts. This document updates “Strategies to Prevent Clostridium difficile Infections in Acute Care Hospitals,” published in 2008. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates

    The novel choline kinase inhibitor ICL-CCIC-0019 reprograms cellular metabolism and inhibits cancer cell growth.

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    The glycerophospholipid phosphatidylcholine is the most abundant phospholipid species of eukaryotic membranes and essential for structural integrity and signaling function of cell membranes required for cancer cell growth. Inhibition of choline kinase alpha (CHKA), the first committed step to phosphatidylcholine synthesis, by the selective small-molecule ICL-CCIC-0019, potently suppressed growth of a panel of 60 cancer cell lines with median GI50 of 1.12 μM and inhibited tumor xenograft growth in mice. ICL-CCIC-0019 decreased phosphocholine levels and the fraction of labeled choline in lipids, and induced G1 arrest, endoplasmic reticulum stress and apoptosis. Changes in phosphocholine cellular levels following treatment could be detected non-invasively in tumor xenografts by [18F]-fluoromethyl-[1,2–2H4]-choline positron emission tomography. Herein, we reveal a previously unappreciated effect of choline metabolism on mitochondria function. Comparative metabolomics demonstrated that phosphatidylcholine pathway inhibition leads to a metabolically stressed phenotype analogous to mitochondria toxin treatment but without reactive oxygen species activation. Drug treatment decreased mitochondria function with associated reduction of citrate synthase expression and AMPK activation. Glucose and acetate uptake were increased in an attempt to overcome the metabolic stress. This study indicates that choline pathway pharmacological inhibition critically affects the metabolic function of the cell beyond reduced synthesis of phospholipids

    Universal Window for Two Dimensional Critical Exponents

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    Two dimensional condensed matter is realised in increasingly diverse forms that are accessible to experiment and of potential technological value. The properties of these systems are influenced by many length scales and reflect both generic physics and chemical detail. To unify their physical description is therefore a complex and important challenge. Here we investigate the distribution of experimentally estimated critical exponents, β\beta, that characterize the evolution of the order parameter through the ordering transition. The distribution is found to be bimodal and bounded within a window 0.1β0.25\sim 0.1 \le \beta \le 0.25, facts that are only in partial agreement with the established theory of critical phenomena. In particular, the bounded nature of the distribution is impossible to reconcile with existing theory for one of the major universality classes of two dimensional behaviour - the XY model with four fold crystal field - which predicts a spectrum of non-universal exponents bounded only from below. Through a combination of numerical and renormalization group arguments we resolve the contradiction between theory and experiment and demonstrate how the "universal window" for critical exponents observed in experiment arises from a competition between marginal operators.Comment: 26 pages, 5 figures and 6 tables. Uses longtable packag

    Monitoring of post-match fatigue in professional soccer: Welcome to the real world

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    Participation in soccer match-play leads to acute and transient subjective, biochemical, metabolic and physical disturbances in players over subsequent hours and days. Inadequate time for rest and regeneration between matches can expose players to the risk of training and competing whilst not entirely recovered. In professional soccer, contemporary competitive schedules can require teams to compete in-excess of 60 matches over the course of the season while periods of fixture congestion occur prompting much attention from researchers and practitioners to the monitoring of fatigue and readiness to play. A comprehensive body of research has investigated post-match acute and residual fatigue responses. Yet the relevance of the research for professional soccer contexts is debatable notably in relation to the study populations and designs employed. Monitoring can indeed be invasive, expensive, time-inefficient and difficult to perform routinely and simultaneously in a large squad of regularly competing players. Uncertainty also exists regarding the meaningfulness and interpretation of changes in fatigue response values and their functional relevance, and practical applicability in the field. The real-world need and cost-benefit of monitoring must be carefully weighed up. In relation to professional soccer contexts, this opinion paper intends to: 1) debate the need for PMF monitoring, 2) critique the real-world relevance of the current research literature, 3) discuss the practical burden relating to measurement tools and protocols and the collection, interpretation and application of data in the field, and, 4) propose future research perspectives

    AMPK activation protects against diet induced obesity through Ucp1-independent thermogenesis in subcutaneous white adipose tissue

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    Obesity results from a chronic imbalance between energy intake and energy output but remains difficult to prevent or treat in humans. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is an important regulator of energy homeostasis1,2,3 and is a molecular target of drugs used for the treatment of metabolic diseases, including obesity4,5. Here we show that mice expressing a gain-of-function AMPK mutant6 display a change in morphology of subcutaneous white adipocytes that is reminiscent of browning. However, despite a dramatic increase in mitochondrial content, Ucp1 expression is undetectable in these adipocytes. In response to a high-fat diet (HFD), expression of skeletal muscle–associated genes is induced in subcutaneous white adipocytes from the gain-of-function AMPK mutant mice. Chronic genetic AMPK activation results in protection against diet-induced obesity due to an increase in whole-body energy expenditure, most probably because of a substantial increase in the oxygen consumption rate of white adipose tissue. These results suggest that AMPK activation enriches, or leads to the emergence of, a population of subcutaneous white adipocytes that produce heat via Ucp1-independent uncoupling of adenosine triphosphate (ATP) production on a HFD. Our findings indicate that AMPK activation specifically in adipose tissue may have therapeutic potential for the treatment of obesity
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