3,270 research outputs found

    Acute otitis media in children presenting to the emergency department: Is it diagnosed and managed appropriately?

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    Aim: To describe the diagnostic and management practice in children with acute otitis media (AOM) presenting to the emergency department (ED) and compare diagnosis and management against existing guidelines. Methods: We performed a retrospective descriptive cohort study of patients ≤15 years of age who presented to two EDs in Southeast Queensland between January 2016 and June 2017 with an ED diagnosis of AOM. Likelihood of diagnosis was based on medical records and classified as likely, possible or unlikely using paediatric practice guidelines. Appropriateness of antibiotics prescription was classified using the National Antibiotic Prescribing Survey, which takes into account adherence to the Australian Therapeutic Guidelines. Each medical record was extracted by two blinded reviewers, and discrepancies were resolved by consensus or arbitration. Results: Of the 305 patients included for analysis, 87% had a likely or possible diagnosis of AOM. Otalgia was the presenting complaint in 75%. Standard otoscopy was the routine method for tympanic membrane visualisation, and 70% had abnormal tympanic membrane findings. Almost two-thirds (62%) of all children were prescribed antibiotics. Antibiotic appropriateness could be ascertained for 286 patients (94%). A total of 39% received inappropriate antibiotic management for AOM. The majority of patients received analgesia in the form of paracetamol and/or ibuprofen. Conclusions: ED clinicians make the diagnosis of AOM fairly accurately, although better assessment of the tympanic membrane by tympanometry and/or pneumatic otoscopy may improve accuracy. More than one-third of patients are prescribed antibiotics inappropriately. Our data can inform knowledge translation and education strategies to ensure the correct evidence-based management of this condition.No Full Tex

    La oratoria, mi identidad universitaria

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    Un día, durante una cita por la tarde con una amiga me llegaron a preguntar: —¿Dónde estudias? — yo respondí —en una universidad que se encuentra ubicada en un pequeño pueblo del estado de México que tal vez no lo conoces... — No terminé de responder cuando ya me tachaban de pueblerino y provinciano, inexperto en tecnología y educación. Pero déjenme contarles, que a pesar de recibir críticas así, yo estoy orgulloso de mi universidad y de haber ingresado al Centro Universitario UAEM Valle de Teotihuacán, ubicado en Santo Domingo Aztacameca, Axapusco Estado de México, en el año 2017

    Pulmonary vein flow split effects in patient-specific simulations of left atrial flow

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    Disruptions to left atrial (LA) blood flow, such as those caused by atrial fibrillation (AF), can lead to thrombosis in the left atrial appendage (LAA) and an increased risk of systemic embolism. LA hemodynamics are influenced by various factors, including LA anatomy and function, and pulmonary vein (PV) inflow conditions. In particular, the PV flow split can vary significantly among and within patients depending on multiple factors. In this study, we investigated how changes in PV flow split affect LA flow transport, focusing for the first time on blood stasis in the LAA, using a high-fidelity patient-specific computational fluid dynamics (CFD) model. We use an Immersed Boundary Method, simulating the flow in a fixed, uniform Cartesian mesh and imposing the movement of the LA walls with a moving Lagrangian mesh generated from 4D Computerized Tomography images. We analyzed LA anatomies from eight patients with varying atrial function, including three with AF and either a LAA thrombus or a history of Transient Ischemic Attacks (TIAs). Using four different flow splits (60/40% and 55/45% through right and left PVs, even flow rate, and same velocity through each PV), we found that flow patterns are sensitive to PV flow split variations, particularly in planes parallel to the mitral valve. Changes in PV flow split also had a significant impact on blood stasis and could contribute to increased risk for thrombosis inside the LAA, particularly in patients with AF and previous LAA thrombus or a history of TIAs. Our study highlights the importance of considering patient-specific PV flow split variations when assessing LA hemodynamics and identifying patients at increased risk for thrombosis and stroke. This knowledge is relevant to planning clinical procedures such as AF ablation or the implementation of LAA occluders.This work was partially supported by Comunidad de Madrid (Synergy Grant Y2018/BIO-4858 PREFI-CM), Spanish Research Agency (AEI, grant number PID2019-107279RB-I00), Instituto de Salud Carlos III (grant numbers PI15/02211-ISBITAMI and DTS/1900063-ISBIFLOW), and by the EU-European Regional Development Fund. Funding for open access charge: Universidad de Málaga /CBU

    Pulmonary vein flow split effects in patient-specific simulations of left atrial flow

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    Disruptions to left atrial (LA) blood flow, such as those caused by atrial fibrillation (AF), can lead to thrombosis in the left atrial appendage (LAA) and an increased risk of systemic embolism. LA hemodynamics are influenced by various factors, including LA anatomy and function, and pulmonary vein (PV) inflow conditions. In particular, the PV flow split can vary significantly among and within patients depending on multiple factors. In this study, we investigated how changes in PV flow split affect LA flow transport, focusing for the first time on blood stasis in the LAA, using a high-fidelity patient-specific computational fluid dynamics (CFD) model. We use an Immersed Boundary Method, simulating the flow in a fixed, uniform Cartesian mesh and imposing the movement of the LA walls with a moving Lagrangian mesh generated from 4D Computerized Tomography images. We analyzed LA anatomies from eight patients with varying atrial function, including three with AF and either a LAA thrombus or a history of Transient Ischemic Attacks (TIAs). Using four different flow splits (60/40% and 55/45% through right and left PVs, even flow rate, and same velocity through each PV), we found that flow patterns are sensitive to PV flow split variations, particularly in planes parallel to the mitral valve. Changes in PV flow split also had a significant impact on blood stasis and could contribute to increased risk for thrombosis inside the LAA, particularly in patients with AF and previous LAA thrombus or a history of TIAs. Our study highlights the importance of considering patient-specific PV flow split variations when assessing LA hemodynamics and identifying patients at increased risk for thrombosis and stroke. This knowledge is relevant to planning clinical procedures such as AF ablation or the implementation of LAA occluders.This work was partially supported by Comunidad de Madrid (Synergy Grant Y2018/BIO-4858 PREFI-CM), Spanish Research Agency (AEI, grant number PID2019-107279RB-I00), Instituto de Salud Carlos III (grant numbers PI15/02211-ISBITAMI and DTS/1900063-ISBIFLOW), and by the EU-European Regional Development Fund . Funding for open access charge: Universidad de Málaga / CBUA

    Efficient multi-fidelity computation of blood coagulation under flow

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    Clot formation is a crucial process that prevents bleeding, but can lead to severe disorders when imbalanced. This process is regulated by the coagulation cascade, a biochemical network that controls the enzyme thrombin, which converts soluble fibrinogen into the fibrin fibers that constitute clots. Coagulation cascade models are typically complex and involve dozens of partial differential equations (PDEs) representing various chemical species’ transport, reaction kinetics, and diffusion. Solving these PDE systems computationally is challenging, due to their large size and multi-scale nature. We propose a multi-fidelity strategy to increase the efficiency of coagulation cascade simulations. Leveraging the slower dynamics of molecular diffusion, we transform the governing PDEs into ordinary differential equations (ODEs) representing the evolution of species concentrations versus blood residence time. We then Taylor-expand the ODE solution around the zero-diffusivity limit to obtain spatiotemporal maps of species concentrations in terms of the statistical moments of residence time, , and provide the governing PDEs for . This strategy replaces a high-fidelity system of N PDEs representing the coagulation cascade of N chemical species by N ODEs and p PDEs governing the residence time statistical moments. The multi-fidelity order (p) allows balancing accuracy and computational cost providing a speedup of over N/p compared to high-fidelity models. Moreover, this cost becomes independent of the number of chemical species in the large computational meshes typical of the arterial and cardiac chamber simulations. Using a coagulation network with N = 9 and an idealized aneurysm geometry with a pulsatile flow as a benchmark, we demonstrate favorable accuracy for low-order models of p = 1 and p = 2. The thrombin concentration in these models departs from the high-fidelity solution by under 20% (p = 1) and 2% (p = 2) after 20 cardiac cycles. These multi-fidelity models could enable new coagulation analyses in complex flow scenarios and extensive reaction networks. Furthermore, it could be generalized to advance our understanding of other reacting systems affected by flow.MGH, MGV and OF have been partially supported by the Spanish Research Agency and the European Regional Development Fund, under grant number PID2019-107279RB-I00. MGH, MGV, PML, JB and OF have been partially supported by the Comunidad de Madrid and the European Regional Development Fund, under grant number Y2018/BIO-4858 PREFI-CM, and by the Instituto de Salud Carlos III and the European Regional Development Fund, under grant numbers PI15/02211-ISBITAMI and DTS/1900063-ISBIFLOW. AG, EMcV, AK and JCdA have been partially supported by the US National Institutes of Health, under grant 1R01HL160024. JCdA has been partially supported by the US National Insitutes of Health, under grant number 1R01HL158667

    Demonstration of Patient-Specific Simulations to Assess Left Atrial Appendage Thrombogenesis Risk

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    Atrial fibrillation (AF) alters left atrial (LA) hemodynamics, which can lead to thrombosis in the left atrial appendage (LAA), systemic embolism and stroke. A personalized risk-stratification of AF patients for stroke would permit improved balancing of preventive anticoagulation therapies against bleeding risk. We investigated how LA anatomy and function impact LA and LAA hemodynamics, and explored whether patient-specific analysis by computational fluid dynamics (CFD) can predict the risk of LAA thrombosis. We analyzed 4D-CT acquisitions of LA wall motion with an in-house immersed-boundary CFD solver. We considered six patients with diverse atrial function, three with either a LAA thrombus (removed digitally before running the simulations) or a history of transient ischemic attacks (LAAT/TIA-pos), and three without a LAA thrombus or TIA (LAAT/TIA-neg). We found that blood inside the left atrial appendage of LAAT/TIA-pos patients had marked alterations in residence time and kinetic energy when compared with LAAT/TIA-neg patients. In addition, we showed how the LA conduit, reservoir and booster functions distinctly affect LA and LAA hemodynamics. Finally, fixed-wall and moving-wall simulations produced different LA hemodynamics and residence time predictions for each patient. Consequently, fixed-wall simulations risk-stratified our small cohort for LAA thrombosis worse than moving-wall simulations, particularly patients with intermediate LAA residence time. Overall, these results suggest that both wall kinetics and LAA morphology contribute to LAA blood stasis and thrombosis.This work was partially supported by the Comunidad de Madrid (Sinergias Y2018/BIO-4858 PREFI-CM), Cátedra Excelencia UC3M-Santander, Ministry of Education of Spain (Salvador de Madariaga program), the US NHLBI (NCAI-UCCAI-2017-06-6), the United States American Heart Association (AHA 20POST35200401), and the 2019 UCSD GEM Program. Computational time provided by XSEDE (Comet) and RES (Altamira) is gratefully acknowledged

    Contemporary presence of dynamical and statistical production of intermediate mass fragments in midperipheral 58^{58}Ni+58^{58}Ni collisions at 30 MeV/nucleon

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    The 58Ni+58Ni^{58}Ni+^{58}Ni reaction at 30 MeV/nucleon has been experimentally investigated at the Superconducting Cyclotron of the INFN Laboratori Nazionali del Sud. In midperipheral collisions the production of massive fragments (4\leZ\le12), consistent with the statistical fragmentation of the projectile-like residue and the dynamical formation of a neck, joining projectile-like and target-like residues, has been observed. The fragments coming from these different processes differ both in charge distribution and isotopic composition. In particular it is shown that these mechanisms leading to fragment production act contemporarily inside the same event.Comment: 9 pages, minor correction

    A Consensus Proposal for Nutritional Indicators to Assess the Sustainability of a Healthy Diet: The Mediterranean Diet as a Case Study

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    BACKGROUND: There is increasing evidence of the multiple effects of diets on public health nutrition, society, and environment. Sustainability and food security are closely interrelated. The traditional Mediterranean Diet (MD) is recognized as a healthier dietary pattern with a lower environmental impact. As a case study, the MD may guide innovative inter-sectorial efforts to counteract the degradation of ecosystems, loss of biodiversity, and homogeneity of diets due to globalization through the improvement of sustainable healthy dietary patterns. This consensus position paper defines a suite of the most appropriate nutrition and health indicators for assessing the sustainability of diets based on the MD. METHODS: In 2011, an informal International Working Group from different national and international institutions was convened. Through online and face-to-face brainstorming meetings over 4 years, a set of nutrition and health indicators for sustainability was identified and refined. RESULTS: Thirteen nutrition indicators of sustainability relating were identified in five areas. Biochemical characteristics of food (A1. Vegetable/animal protein consumption ratios; A2. Average dietary energy adequacy; A3. Dietary Energy Density Score; A4. Nutrient density of diet), Food Quality (A5. Fruit and vegetable consumption/intakes; A6. Dietary Diversity Score), Environment (A7. Food biodiversity composition and consumption; A8. Rate of Local/regional foods and seasonality; A9. Rate of eco-friendly food production and/or consumption), Lifestyle (A10. Physical activity/physical inactivity prevalence; A11. Adherence to the Mediterranean dietary pattern), Clinical Aspects (A12. Diet-related morbidity/mortality statistics; A13. Nutritional Anthropometry). A standardized set of information was provided for each indicator: definition, methodology, background, data sources, limitations of the indicator, and references. CONCLUSION: The selection and analysis of these indicators has been performed (where possible) with specific reference to the MD. Sustainability of food systems is an urgent priority for governments and international organizations to address the serious socioeconomic and environmental implications of short-sighted and short-term practices for agricultural land and rural communities. These proposed nutrition indicators will be a useful methodological framework for designing health, education, and agricultural policies in order, not only to conserve the traditional diets of the Mediterranean area as a common cultural heritage and lifestyle but also to enhance the sustainability of diets in general
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