304 research outputs found

    A Heart of Flesh

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    The utility of eccentricity index as a measure of right ventricular function in a lung resection cohort

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    Context: Right ventricular (RV) dysfunction occurs after lung resection and is associated with postoperative morbidity. Noninvasive evaluation of the RV is challenging, particularly in the postoperative period. A reliable measure of RV function would have value in this population. Aims: This study compares eccentricity index (EI) obtained by transthoracic echocardiography (TTE) with cardiovascular magnetic resonance (CMR) determined measures of RV function in a lung resection cohort. CMR is the reference method for noninvasive assessment of RV function. Design and Setting: Prospective observational cohort study at a single tertiary hospital. Materials and Methods: Twenty-eight patients scheduled for elective lung resection underwent contemporaneous TTE and CMR imaging preoperatively, on postoperative day (POD) 2 and at 2-month. Systolic and diastolic EI was measured offline from anonymized and randomized TTE and CMR images. Statistical Analysis: Bland–Altman analysis was performed to determine agreement between EITTE and EICMR. Changes over time and comparison with CMR determined RV ejection fraction (RVEFCMR) was assessed. Results: Bland–Altman analysis showed a negligible mean difference between EITTE and EICMR, but limits of agreement were wide (SD 0.24 and 0.28). There were no significant changes in EITTE and EICMR over time (P > 0.35). We found no association between EITTE with RVEFCMR at all-time points (P > 0.22). Systolic and diastolic EICMR on POD 2 demonstrated moderate association with RVEFCMR (r = −0.54 and r = −0.59, P ≤ 0.01). At 2-month, only diastolic EICMR correlated with RVEFCMR (r = −0.43, P = 0.03). There were no meaningful associations between EITTE and EICMR with TTE-derived RV systolic pressure (P > 0.31). Conclusions: TTE determined EI is not useful as a noninvasive method of assessing RV function following lung resection

    The Measure of Youth Policy Arguments: An Approach to Supporting Democratic Participation and Student Voice

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    Although experiential approaches to democracy education are gaining increased support from educators and scholars, few educational resources exist to support youth in constructing and delivering high-quality, evidence-based policy arguments to authentic audiences. Such presentations are often the first time that young people step into the public sphere and speak to public officials; they represent rich opportunities for youth political development and activism. In this paper, we introduce an assessment tool, called the Measure of Youth Policy Arguments (MYPA), which is intended to be a resource for community and school educators. Drawing on data from two years of field-testing and iterative co-design in the context of research-practice partnerships (RPPs), we chronicle the development of the tool and provide evidence about its educational uses in classrooms and community programs. In the discussion section, we explain key decisions in the development of MYPA and how those shaped its appropriateness for certain uses and lack of appropriateness for others

    Nutritional intakes of patients at risk of pressure ulcers in the clinical setting

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    Objective: Malnutrition is a risk factor for pressure ulcers. The aim of this study was to describe the energy and protein intakes of hospitalized patients at risk for pressure ulcers and to identify predictors of eating inadequately

    The utility of trans thoracic echocardiograhic measures of right ventricular systolic function in a lung resection cohort

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    Right ventricular (RV) dysfunction occurs following lung resection and is associated with post-operative complications and long-term functional morbidity. Accurate peri-operative assessment of RV function would have utility in this population. The difficulties of transthoracic echocardiographic (TTE) assessment of RV function may be compounded following lung resection surgery, and no parameters have been validated in this patient group. This study compares conventional TTE methods for assessing RV systolic function to a reference method in a lung resection population. Right ventricular index of myocardial performance (RIMP), fractional area change (FAC), tricuspid annular plane systolic excursion (TAPSE) and S′ wave velocity at the tricuspid annulus (S′), along with speckle tracked global and free wall longitudinal strain (RV-GPLS and RV-FWPLS respectively) are compared with RV ejection fraction obtained by cardiovascular magnetic resonance (RVEFCMR). Twenty-seven patients undergoing lung resection underwent contemporaneous CMR and TTE imaging; pre-operatively, on post-operative day two and at 2 months. Ability of each of the parameters to predict RV dysfunction (RVEFCMR <45%) was assessed using the area under the receiver operating characteristic curve (AUROCC). RIMP, FAC and S′ demonstrated no predictive value for poor RV function (AUROCC <0.61, P > 0.05). TAPSE performed marginally better with an AUROCC of 0.65 (P = 0.04). RV-GPLS and RV-FWPLS demonstrated good predictive ability with AUROCC’s of 0.74 and 0.76 respectively (P < 0.01 for both). This study demonstrates that the conventional TTE parameters of RV systolic function are inadequate following lung resection. Longitudinal strain performs better and offers some ability to determine poor RV function in this challenging population

    Coarse-Grained Models of Biological Membranes within the Single Chain Mean Field Theory

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    The Single Chain Mean Field theory is used to simulate the equilibrium structure of phospholipid membranes at the molecular level. Three levels of coarse-graining of DMPC phospholipid surfactants are present: the detailed 44-beads double tails model, the 10-beads double tails model and the minimal 3-beads model. We show that all three models are able to reproduce the essential equilibrium properties of the phospholipid bilayer, while the simplest 3-beads model is the fastest model which can describe adequately the thickness of the layer, the area per lipid and the rigidity of the membrane. The accuracy of the method in description of equilibrium structures of membranes compete with Monte Carlo simulations while the speed of computation and the mean field nature of the approach allows for straightforward applications to systems with great complexity.Comment: Accepted for publication in Soft Matte

    Don’t forget the right ventricle

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    In their recent article, González-Tallada et al. demonstrated an incidence of myocardial injury after noncardiac surgery (MINS) in 27.3% of patients undergoing thoracic surgery.1 MINS was defined as a postoperative troponin I level >0.04 ng/mL (>99th percentile) without evidence of a nonischemic cause of troponin I elevation. Independent association was demonstrated between occurrence of MINS and both smoking and extent of resection (lobectomy or pneumonectomy compared with other types of resection)

    Comment on propofol and survival: an updated meta-analysis of randomized clinical trials

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    No abstract available

    Wildlife-friendly farming increases crop yield: evidence for ecological intensification

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    Ecological intensification has been promoted as a means to achieve environmentally sustainable increases in crop yields by enhancing ecosystem functions that regulate and support production. There is, however, little direct evidence of yield benefits from ecological intensification on commercial farms growing globally important foodstuffs (grains, oilseeds and pulses). We replicated two treatments removing 3 or 8% of land at the field edge from production to create wildlife habitat in 50–60 ha patches over a 900 ha commercial arable farm in central England, and compared these to a business as usual control (no land removed). In the control fields, crop yields were reduced by as much as 38% at the field edge. Habitat creation in these lower yielding areas led to increased yield in the cropped areas of the fields, and this positive effect became more pronounced over 6 years. As a consequence, yields at the field scale were maintained—and, indeed, enhanced for some crops—despite the loss of cropland for habitat creation. These results suggested that over a 5-year crop rotation, there would be no adverse impact on overall yield in terms of monetary value or nutritional energy. This study provides a clear demonstration that wildlife-friendly management which supports ecosystem services is compatible with, and can even increase, crop yields
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