880 research outputs found

    Computing in medicine: a role-play supports diagnosis and assessment of diseases in patients

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    Computing is a principle of leading data visualisation, translation and findings of new information. In medicine, understanding and reading medical images are crucial to analyse and assess medical data before making a decision and treatment for patients. Computational modelling, simulation and technology enable to form the digital medicine and gain new knowledge to develop non-invasive techniques for diagnosis and assessment of diseases in patients. This talk covers the current state of the art non-invasive imaging approaches and predicts the trends of computing and machine learning in medicine and healthcare

    Interannual variability in the summer dissolved organic matter inventory of the North Sea: Implications for the continental shelf pump

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    We present the distribution and C:N stoichiometry of dissolved organic matter (DOM) in the North Sea in two summers (August 2011 and August 2012), with supporting data from the intervening winter (January 2012). These data demonstrate local variability superimposed on a general pattern of decreasing DOM with increasing distance from land, suggesting concentrations of DOM are controlled on large spatial scales by mixing between the open North Atlantic and either riverine sources or high DOM productivity in nearshore coastal waters driven by riverine nutrient discharge. Given the large size and long residence time of water in the North Sea, we find concentrations are commonly modified from simple conservative mixing between two endmembers. We observe differences in dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) concentrations and land-ocean gradients between the two summers, leading to an estimated 10-20Tg difference in the DOC inventory between the two years, which is of the same order of magnitude as the annual uptake of atmospheric CO 2 by the North Sea system, and thus significant for the carbon budget of the North Sea. This difference is not consistent with additional terrestrial loading and is more likely to be due to balancing of mixing and in situ production and loss processes across the North Sea. Differences were particularly pronounced in the bottom layer of the seasonally stratifying northern North Sea, with higher DOC and C:N ratio in 2011 than in 2012. Using other data, we consider the extent to which these differences in the concentrations and C:N ratio of DOM could be due to changes in the biogeochemistry or physical circulation in the two years, or a combination of both. The evidence we have is consistent with a flushing event in winter 2011/12 exchanging DOM-rich, high C:N shelf waters, which may have accumulated over more than 1 year, with deep North Atlantic waters with lower DOC and marginally higher DON. We discuss the implications of these observations for the shelf sea carbon pump and the export of carbon-rich organic matter off the shelf and hypothesise that intermittent flushing of temperate shelf systems may be a key mechanism in the maintenance of the continental shelf pump, via the accumulation and subsequent export of carbon-rich DOM

    Maritime Computing Transportation, Environment, and Development: Trends of Data Visualization and Computational Methodologies

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    This research aims to characterize the field of maritime computing (MC) transportation, environment, and development. It is the first report to discover how MC domain configurations support management technologies. An aspect of this research is the creation of drivers of ocean-based businesses. Systematic search and meta-analysis are employed to classify and define the MC domain. MC developments were first identified in the 1990s, representing maritime development for designing sailboats, submarines, and ship hydrodynamics. The maritime environment is simulated to predict emission reductions, coastal waste particles, renewable energy, and engineer robots to observe the ocean ecosystem. Maritime transportation focuses on optimizing ship speed, maneuvering ships, and using liquefied natural gas and submarine pipelines. Data trends with machine learning can be obtained by collecting a big data of similar computational results for implementing artificial intelligence strategies. Research findings show that modeling is an essential skill set in the 21st century

    Viscosity Approximation Method for System of Variational Inclusions Problems and Fixed-Point Problems of a Countable Family of Nonexpansive Mappings

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    We propose new iterative schemes for finding the common element of the set of common fixed points of countable family of nonexpansive mappings, the set of solutions of the variational inequality problem for relaxed cocoercive and Lipschitz continuous, the set of solutions of system of variational inclusions problem, and the set of solutions of equilibrium problems in a real Hilbert space by using the viscosity approximation method. We prove strong convergence theorem under some parameters. The results in this paper unify and generalize some well-known results in the literature

    An investigation of correlation between left coronary bifurcation angle and hemodynamic changes in coronary stenosis by coronary computed tomography angiography-derived computational fluid dynamics

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    Background: To investigate the correlation between left coronary bifurcation angle and coronary stenosis as assessed by coronary computed tomography angiography (CCTA)-generated computational fluid dynamics (CFD) analysis when compared to the CCTA analysis of coronary lumen stenosis and plaque lesion length with invasive coronary angiography (ICA) as the reference method. Methods: Thirty patients (22 males, mean age: 59±6.9 years) with calcified plaques at the left coronary artery were included in the study with all patients undergoing CCTA and ICA examinations. CFD simulation was performed to analyze hemodynamic changes to the left coronary artery models in terms of wall shear stress, wall pressure and flow velocity, with findings correlated to the coronary stenosis and degree of bifurcation angle. Calcified plaque length was measured in the left coronary artery with diagnostic value compared to that from coronary lumen and bifurcation angle assessments. Results: Of 26 significant stenosis at left anterior descending (LAD) and 13 at left circumflex (LCx) on CCTA, only 14 and 5 of them were confirmed to be >50% stenosis at LAD and LCx respectively on ICA, resulting in sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 100%, 52%, 49% and 100%. The mean plaque length was measured 5.3±3.6 and 4.4±1.9 mm at LAD and LCx, respectively, with diagnostic sensitivity, specificity, PPV and NPV being 92.8%, 46.7%, 61.9% and 87.5% for extensively calcified plaques. The mean bifurcation angle was measured 83.9±13.6º and 83.8±13.3º on CCTA and ICA, respectively, with no significant difference (P=0.98). The corresponding sensitivity, specificity, PPV and NPV were 100%, 78.6%, 84.2% and 100% based on bifurcation angle measurement on CCTA, 100%, 73.3%, 78.9% and 100% based on bifurcation angle measurements on ICA, respectively. Wall shear stress was noted to increase in the LAD and LCx models with significant stenosis and wider angulation (>80º), but demonstrated little or no change in most of the coronary models with no significant stenosis and narrower angulation (<80º). Conclusions: This study further clarifies the relationship between left coronary bifurcation angle and significant stenosis, with angulation measurement serving as a more accurate approach than coronary lumen assessment or plaque lesion length for determining significant coronary stenosis. Left coronary bifurcation angle is suggested to be incorporated into coronary artery disease (CAD) assessment when diagnosing significant CAD

    How are psychological capital and emotion regulation associated with schoolteachers’ burnout? A systematic review

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    Teachers are one of the professions that suffer from burnout, which has negative effects not only on teachers but also on their students. This systematic review aimed to examine the relationships between psychological capital, emotion regulation, and burnout among schoolteachers. The review was based on electronic databases including SCOPUS, PubMed, and ERIC and included 10 original articles that met the inclusion and exclusion criteria. The findings showed that higher levels of psychological capital and emotion regulation were negatively associated with burnout and its dimensions. Additionally, cognitive reappraisal was found to have a negative effect on burnout, while expressive suppression was positively associated with burnout. This systematic review could be useful in developing interventions and guidelines to improve psychological capital and emotion regulation, and prevent burnout in schoolteachers, leading to better well-being

    Computational fluid dynamics analysis of the effect of simulated plaques in the left coronary artery: A preliminary study

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    Background: Atherosclerosis is the most common cause of coronary artery disease which is formed by plaque presence inside the artery wall leading to blockage of the blood supply to the heart muscle. The mechanism of atherosclerotic development is dependent on the blood flow variations in the artery wall during cardiac cycles. Characterization of plaque components and investigation of the plaques with subsequent coronary artery stenosis and myocardial dysfunction has been extensively studied in the literature. However, little is known about the effect of plaques on hemodynamic changes to the coronary artery, to the best of our knowledge. Investigation of the position of plaques in the coronary artery and its corresponding regional hemodynamic effects will provide valuable information for prediction of the coronary artery disease progression. The aim of this study is to investigate the effect of simulated plaques in the left coronary artery using computational fluid dynamics. Methods: A left coronary artery model was generated based on a computed tomography data in a patient suspected of coronary artery disease. The model consists of the left main coronary artery, left anterior descending and left circumflex, together with side branches. Simulated coronary plaques were created and placed in the left main coronary artery and left anterior descending with a resultant lumen stenosis of more than 50%. The blood rheology and pulsatile velocity at the left coronary artery were applied to simulate the realistic physiological situation. A transient simulation was performed to demonstrate the hemodynamic changes during cardiac phases. The flow velocity pattern, wall shear stress and wall pressure were measured at peak systolic and middle diastolic phases in the models with and without presence of plaques. Results: Our results showed that the flow change due to the simulated coronary plaques demonstrated a large circulation region at the left coronary bifurcation, and the velocity through bifurcation was increased. In contrast, a smooth flow pattern was observed in the non-calcified regions and flow velocity was low at the bifurcation. Low wall pressure was present in the coronary artery with a simulated coronary plaque whereas there was high wall pressure in the normal coronary artery. The simulated plaques resulted in high wall shear stress when compared to the low wall shear stress present in the normal coronary artery. The simulated coronary plaques interfered with blood flow behavior which was demonstrated as a large region of disturbed flow at coronary bifurcation. Conclusion: We successfully simulated the coronary plaques in a realistic coronary model and the effect of plaques in different locations on subsequent hemodynamic changes. Our preliminary study is useful for further investigation of the development of atherosclerosis in patients with different cardiac risk factors
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