54 research outputs found

    Physiological and Psychological Effects of Deception on Pacing Strategy and Performance: A Review

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    The aim of an optimal pacing strategy during exercise is to enhance performance whilst ensuring physiological limits are not surpassed, which has been shown to result in a metabolic reserve at the end of the exercise. There has been debate surrounding the theoretical models that have been proposed to explain how pace is regulated, with more recent research investigating a central control of exercise regulation. Deception has recently emerged as a common, practical approach to manipulate key variables during exercise. There are a number of ways in which deception interventions have been designed, each intending to gain particular insights into pacing behaviour and performance. Deception methodologies can be conceptualised according to a number of dimensions such as deception timing (prior to or during exercise), presentation frequency (blind, discontinuous or continuous) and type of deception (performance, biofeedback or environmental feedback). However, research evidence on the effects of deception has been perplexing and the use of complex designs and varied methodologies makes it difficult to draw any definitive conclusions about how pacing strategy and performance are affected by deception. This review examines existing research in the area of deception and pacing strategies, and provides a critical appraisal of the different methodological approaches used to date. It is hoped that this analysis will inform the direction and methodology of future investigations in this area by addressing the mechanisms through which deception impacts upon performance and by elucidating the potential application of deception techniques in training and competitive settings

    Repaired tetralogy of Fallot: the roles of cardiovascular magnetic resonance in evaluating pathophysiology and for pulmonary valve replacement decision support

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    Surgical management of tetralogy of Fallot (TOF) results in anatomic and functional abnormalities in the majority of patients. Although right ventricular volume load due to severe pulmonary regurgitation can be tolerated for many years, there is now evidence that the compensatory mechanisms of the right ventricular myocardium ultimately fail and that if the volume load is not eliminated or reduced by pulmonary valve replacement the dysfunction might be irreversible. Cardiovascular magnetic resonance (CMR) has evolved during the last 2 decades as the reference standard imaging modality to assess the anatomic and functional sequelae in patients with repaired TOF. This article reviews the pathophysiology of chronic right ventricular volume load after TOF repair and the risks and benefits of pulmonary valve replacement. The CMR techniques used to comprehensively evaluate the patient with repaired TOF are reviewed and the role of CMR in supporting clinical decisions regarding pulmonary valve replacement is discussed

    Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

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    BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    High surface area networks from tetrahedral monomers: metal-catalyzed coupling, thermal polymerization, and “click” chemistry

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    A series of tetrahedrally linked conjugated microporous polymer networks were prepared using a variety of bond-forming chemistries including Sonogashira−Hagihara coupling, Yamamoto coupling, thermal alkyne condensation, and “click” chemistry. These thermally stable polymers exhibit high surface areas (up to 3200 m2/g) and adsorb up to 2.34 wt % hydrogen by mass at 1.13 bar/77 K and 7.59 wt % carbon dioxide by mass at 1.13 bar/298 K

    Microporous organic polymers for carbon dioxide capture

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    Anthropogenic carbon dioxide emissions are thought to be one cause of global warming. Current methods for CO2 capture result in large energy penalties. Solid adsorbents are a potential method to capture CO2, but the sorbent-sorbate affinity is critical in determining the energetic viability of such processes. In this study, the adsorption of CO2 in a range of microporous organic polymers was tested. These materials adsorb up to 2.20 mmol/g CO2 at 298 K and 1 bar, and thus performance is compared with related porous solids in the literature. The relationship between CO2 uptake and apparent surface area and pore size is described, and this showed that heats of adsorption were important in the low pressure regime. The chemical tuning of gas-sorbent affinity provides a blueprint for the development of improved materials in this area

    2006 Winter Dairy Management Series Enhance Dairy Profitability: Achieve Balance Between Crops and Cows

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    This information was presented at the 2006 Winter Dairy Management Conference, organized by the PRO-DAIRY program in the College of Agriculture and Life Sciences at Cornell University. This collaborative effort between PRO-DAIRY, dairy producers, agri-business professionals and Cornell Cooperative Extension educators brings technical, financial and operational know-how to a topic of importance to dairy farms. Seminars are offered across New York State each year. Softcover copies of the entire conference proceedings may be purchased at http://www.ansci.cornell.edu/dm/proceedings_orders.html or by calling (607) 255-4285

    Enhance Dairy Profitability: Achieve Balance Between Crops and Cows - Part 2

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    This information was presented at the 2009 Winter Dairy Management Conference, organized by the PRO-DAIRY program in the College of Agriculture and Life Sciences at Cornell University. This collaborative effort between PRO-DAIRY, dairy producers, agri-business professionals and Cornell Cooperative Extension educators brings technical, financial and operational know-how to a topic of importance to dairy farms. Seminars are offered across New York State each year. Softcover copies of the entire conference proceedings may be purchased at http://www.ansci.cornell.edu/dm/proceedings_orders.html or by calling (607) 255-4285

    2006 Winter Dairy Management Series Enhance Dairy Profitability: Achieve Balance Between Crops and Cows

    Full text link
    This information was presented at the 2006 Winter Dairy Management Conference, organized by the PRO-DAIRY program in the College of Agriculture and Life Sciences at Cornell University. This collaborative effort between PRO-DAIRY, dairy producers, agri-business professionals and Cornell Cooperative Extension educators brings technical, financial and operational know-how to a topic of importance to dairy farms. Seminars are offered across New York State each year. Softcover copies of the entire conference proceedings may be purchased at http://www.ansci.cornell.edu/dm/proceedings_orders.html or by calling (607) 255-4285
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