32 results on '"Eikonal model"'
Search Results
2. Refining the Eikonal Model to Reproduce the Influence of Atrial Tissue Geometry on Conduction Velocity
- Author
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Skupien Nils, Barrios Espinosa Cristian, Dössel Olaf, and Loewe Axel
- Subjects
cardiac modelling ,eikonal model ,conduction velocity ,wall thickness ,tissue curvature ,atrial fibrillation ,Medicine - Abstract
Atrial fibrillation is responsible for a significant and steadily rising burden. Simultaneously, the treatment options for atrial fibrillation are far from optimal. Personalized simulations of cardiac electrophysiology could assist clinicians in the risk stratification and therapy planning for atrial fibrillation. However, the use of personalized simulations in clinics is currently not possible due to either too high computational costs or non-sufficient accuracy. Eikonal simulations come with low computational costs but cannot replicate the influence of cardiac tissue geometry on the conduction velocity of the wave propagation. Consequently, they currently lack the required accuracy to be applied in clinics. Biophysically detailed simulations on the other hand are accurate but associated with too high computational costs. To tackle this issue, a regression model is created based on biophysically detailed bidomain simulation data. This regression formula calculates the conduction velocity dependent on the thickness and curvature of the heart wall. Afterwards the formula was implemented into the eikonal model with the goal to increase the accuracy of the eikonal model without losing its advantage of computational efficiency. The results of the modified eikonal simulations demonstrate that (i) the local activation times become significantly closer to those of the biophysically detailed bidomain simulations, (ii) the advantage of the eikonal model of a low sensitivity to the resolution of the mesh was reduced further, and (iii) the unrealistic occurrence of endo-epicardial dissociation in simulations was remedied. The results suggest that the accuracy of the eikonal model was significantly increased. At the same time, the additional computational costs caused by the implementation of the regression formula are neglectable. In conclusion, a successful step towards a more accurate and fast computational model of cardiac electrophysiology was achieved.
- Published
- 2022
- Full Text
- View/download PDF
3. Spiral Waves Generation Using an Eikonal-Reaction Cardiac Electrophysiology Model
- Author
-
Gassa, Narimane, Zemzemi, Nejib, Corrado, Cesare, Coudière, Yves, Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Ennis, Daniel B., editor, Perotti, Luigi E., editor, and Wang, Vicky Y., editor
- Published
- 2021
- Full Text
- View/download PDF
4. A fast cardiac electromechanics model coupling the Eikonal and the nonlinear mechanics equations.
- Author
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Stella, Simone, Regazzoni, Francesco, Vergara, Christian, Dedé, Luca, and Quarteroni, Alfio
- Subjects
- *
NONLINEAR mechanics , *NONLINEAR equations , *TISSUE mechanics , *CONTRACTILITY (Biology) , *BLOOD circulation , *CIRCULATION models , *ELECTROPHYSIOLOGY - Abstract
We present a new model of human cardiac electromechanics for the left ventricle where electrophysiology is described by a Reaction–Eikonal model and which enables an off-line resolution of the reaction model, thus entailing a big saving of computational time. Subcellular dynamics is coupled with a model of tissue mechanics, which is in turn coupled with a Windkessel model for blood circulation. Our numerical results show that the proposed model is able to provide a physiological response to changes in certain variables (end-diastolic volume, total peripheral resistance, contractility). We also show that our model is able to reproduce with high accuracy and with a considerably lower computational time the results that we would obtain if the monodomain model should be used in place of the Eikonal model. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
5. Reconstruction of three-dimensional biventricular activation based on the 12-lead electrocardiogram via patient-specific modelling.
- Author
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Pezzuto, Simone, Prinzen, Frits W, Potse, Mark, Maffessanti, Francesco, Regoli, François, Caputo, Maria Luce, Conte, Giulio, Krause, Rolf, and Auricchio, Angelo
- Subjects
ARTHRITIS Impact Measurement Scales ,BODY surface mapping ,MAGNETIC resonance imaging ,HEART ventricles ,ELECTROCARDIOGRAPHY - Abstract
Aims: Non-invasive imaging of electrical activation requires high-density body surface potential mapping. The nine electrodes of the 12-lead electrocardiogram (ECG) are insufficient for a reliable reconstruction with standard inverse methods. Patient-specific modelling may offer an alternative route to physiologically constraint the reconstruction. The aim of the study was to assess the feasibility of reconstructing the fully 3D electrical activation map of the ventricles from the 12-lead ECG and cardiovascular magnetic resonance (CMR).Methods and Results: Ventricular activation was estimated by iteratively optimizing the parameters (conduction velocity and sites of earliest activation) of a patient-specific model to fit the simulated to the recorded ECG. Chest and cardiac anatomy of 11 patients (QRS duration 126-180 ms, documented scar in two) were segmented from CMR images. Scar presence was assessed by magnetic resonance (MR) contrast enhancement. Activation sequences were modelled with a physiologically based propagation model and ECGs with lead field theory. Validation was performed by comparing reconstructed activation maps with those acquired by invasive electroanatomical mapping of coronary sinus/veins (CS) and right ventricular (RV) and left ventricular (LV) endocardium. The QRS complex was correctly reproduced by the model (Pearson's correlation r = 0.923). Reconstructions accurately located the earliest and latest activated LV regions (median barycentre distance 8.2 mm, IQR 8.8 mm). Correlation of simulated with recorded activation time was very good at LV endocardium (r = 0.83) and good at CS (r = 0.68) and RV endocardium (r = 0.58).Conclusion: Non-invasive assessment of biventricular 3D activation using the 12-lead ECG and MR imaging is feasible. Potential applications include patient-specific modelling and pre-/per-procedural evaluation of ventricular activation. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
6. Reliable extraction of the dB(E1)/dE for 11Be from its breakup at 520 MeV/nucleon.
- Author
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Moschini, L. and Capel, P.
- Subjects
- *
NUCLEAR halos , *PARTICLES (Nuclear physics) , *SPECIAL relativity (Physics) , *COULOMB functions , *NUCLEAR reactions , *EIKONAL equation - Abstract
Abstract We analyze the breakup of the one-neutron halo nucleus 11Be measured at 520 MeV/nucleon at GSI on Pb and C targets within an eikonal description of the reaction including a proper treatment of special relativity. The Coulomb term of the projectile-target interaction is corrected at first order, while its nuclear part is described at the optical limit approximation. Good agreement with the data is obtained using a description of 11Be, which fits the breakup data of RIKEN. This solves the apparent discrepancy between the d B (E1) / d E estimations from GSI and RIKEN for this nucleus. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
7. Parametrization of activation based cardiac electrophysiology models using bidomain model simulations
- Author
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Stender Birgit
- Subjects
bidomain model ,cardiac electrophysiology ,conduction velocity ,eikonal model ,monodomain model ,Medicine - Abstract
Eikonal models are useful to compute approximate solutions of cardiac excitation propagation in a computationally efficient way. In this work the underlying conduction velocities for different cell types were computed solving the classical bidomain model equations for planar wavefront propagation. It was further investigated how changes in the conductivity tensors within the bidomain model analytically correspond to changes in the conduction velocity. The error in the presence of local front curvature for the derived eikonal model parametrization were analyzed. The conduction velocity simulated based on the bidomain model was overestimated by a maximum of 10%.
- Published
- 2016
- Full Text
- View/download PDF
8. Evaluation of a Rapid Anisotropic Model for ECG Simulation
- Author
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Simone Pezzuto, Peter Kal'avský, Mark Potse, Frits W. Prinzen, Angelo Auricchio, and Rolf Krause
- Subjects
ECG ,eikonal model ,lead fields ,bidomain modeling ,patient-specific modeling ,electrophysiology ,Physiology ,QP1-981 - Abstract
State-of-the-art cardiac electrophysiology models that are able to deliver physiologically motivated activation maps and electrocardiograms (ECGs) can only be solved on high-performance computing architectures. This makes it nearly impossible to adopt such models in clinical practice. ECG imaging tools typically rely on simplified models, but these neglect the anisotropic electric conductivity of the tissue in the forward problem. Moreover, their results are often confined to the heart-torso interface. We propose a forward model that fully accounts for the anisotropic tissue conductivity and produces the standard 12-lead ECG in a few seconds. The activation sequence is approximated with an eikonal model in the 3d myocardium, while the ECG is computed with the lead-field approach. Both solvers were implemented on graphics processing units and massively parallelized. We studied the numerical convergence and scalability of the approach. We also compared the method to the bidomain model in terms of ECGs and activation maps, using a simplified but physiologically motivated geometry and 6 patient-specific anatomies. The proposed methods provided a good approximation of activation maps and ECGs computed with a bidomain model, in only a few seconds. Both solvers scaled very well to high-end hardware. These methods are suitable for use in ECG imaging methods, and may soon become fast enough for use in interactive simulation tools.
- Published
- 2017
- Full Text
- View/download PDF
9. Reconstruction of three-dimensional biventricular activation based on the 12-lead electrocardiogram via patient-specific modelling
- Author
-
Frits W. Prinzen, Giulio Conte, Rolf Krause, Simone Pezzuto, Mark Potse, Maria Luce Caputo, François Regoli, Angelo Auricchio, Francesco Maffessanti, Fysiologie, RS: Carim - H06 Electro mechanics, Clinical sciences, Center for Computational Medicine in Cardiology (CCMC), Università della Svizzera italiana = University of Italian Switzerland (USI), Cardiovascular Research Institute Maastricht (CARIM), Maastricht University [Maastricht], IHU-LIRYC, Université Bordeaux Segalen - Bordeaux 2-CHU Bordeaux [Bordeaux], Modélisation et calculs pour l'électrophysiologie cardiaque (CARMEN), Institut de Mathématiques de Bordeaux (IMB), Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Inria Bordeaux - Sud-Ouest, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-IHU-LIRYC, Université Bordeaux Segalen - Bordeaux 2-CHU Bordeaux [Bordeaux]-CHU Bordeaux [Bordeaux], Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS), Cardiocentro Ticino [Lugano], Universität Zürich [Zürich] = University of Zurich (UZH), Theo Rossi di Montelera Foundation (Lausanne, Switzerland), Metis Foundation Sergio Mantegazza (Lugano, Switzerland), Fidinam Foundation (Lugano, Swizerland), Swiss Heart Foundation (Bern, Switzerland), SNSF project 32003B_165802 (Bern, Switzerland), Horten Foundation (Castelrotto, Switzerland), and CSCS—Swiss National Supercomputing Centre production grant s778 (Lugano, Switzerland)., University of Zurich, Pezzuto, Simone, Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Inria Bordeaux - Sud-Ouest, and Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
CARDIAC ELECTROPHYSIOLOGY ,medicine.medical_specialty ,Patient-specific modelling ,Heart Ventricles ,0206 medical engineering ,12 lead electrocardiogram ,610 Medicine & health ,02 engineering and technology ,030204 cardiovascular system & hematology ,Heart Ventricles/diagnostic imaging ,Techincal Issues ,11171 Cardiocentro Ticino ,2705 Cardiology and Cardiovascular Medicine ,Nerve conduction velocity ,VALIDATION ,03 medical and health sciences ,QRS complex ,Electrocardiography ,2737 Physiology (medical) ,0302 clinical medicine ,[SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system ,Physiology (medical) ,Internal medicine ,Eikonal model ,medicine ,Humans ,magnetic resonance imaging ,AcademicSubjects/MED00200 ,cardiovascular diseases ,Endocardium ,Coronary sinus ,medicine.diagnostic_test ,Ventricular activation • Three-dimensional activation ,business.industry ,Cardiac electrophysiology ,Body Surface Potential Mapping ,Magnetic resonance imaging ,020601 biomedical engineering ,Three-dimensional activation ,Ventricular activation ,Twelve-lead electrocardiogram ,Cardiology ,cardiovascular system ,patient-specific modeling ,business ,Cardiology and Cardiovascular Medicine - Abstract
Aims Non-invasive imaging of electrical activation requires high-density body surface potential mapping. The nine electrodes of the 12-lead electrocardiogram (ECG) are insufficient for a reliable reconstruction with standard inverse methods. Patient-specific modelling may offer an alternative route to physiologically constraint the reconstruction. The aim of the study was to assess the feasibility of reconstructing the fully 3D electrical activation map of the ventricles from the 12-lead ECG and cardiovascular magnetic resonance (CMR). Methods and results Ventricular activation was estimated by iteratively optimizing the parameters (conduction velocity and sites of earliest activation) of a patient-specific model to fit the simulated to the recorded ECG. Chest and cardiac anatomy of 11 patients (QRS duration 126–180 ms, documented scar in two) were segmented from CMR images. Scar presence was assessed by magnetic resonance (MR) contrast enhancement. Activation sequences were modelled with a physiologically based propagation model and ECGs with lead field theory. Validation was performed by comparing reconstructed activation maps with those acquired by invasive electroanatomical mapping of coronary sinus/veins (CS) and right ventricular (RV) and left ventricular (LV) endocardium. The QRS complex was correctly reproduced by the model (Pearson’s correlation r = 0.923). Reconstructions accurately located the earliest and latest activated LV regions (median barycentre distance 8.2 mm, IQR 8.8 mm). Correlation of simulated with recorded activation time was very good at LV endocardium (r = 0.83) and good at CS (r = 0.68) and RV endocardium (r = 0.58). Conclusion Non-invasive assessment of biventricular 3D activation using the 12-lead ECG and MR imaging is feasible. Potential applications include patient-specific modelling and pre-/per-procedural evaluation of ventricular activation.
- Published
- 2021
10. Efficient computation of electrograms and ECGs in human whole heart simulations using a reaction-eikonal model.
- Author
-
Neic, Aurel, Campos, Fernando O., Prassl, Anton J., Niederer, Steven A., Bishop, Martin J., Vigmond, Edward J., and Plank, Gernot
- Subjects
- *
ELECTROCARDIOGRAPHY , *EIKONAL equation , *ELECTROPHYSIOLOGY , *PURKINJE fibers , *SIMULATION methods & models - Abstract
Anatomically accurate and biophysically detailed bidomain models of the human heart have proven a powerful tool for gaining quantitative insight into the links between electrical sources in the myocardium and the concomitant current flow in the surrounding medium as they represent their relationship mechanistically based on first principles. Such models are increasingly considered as a clinical research tool with the perspective of being used, ultimately, as a complementary diagnostic modality. An important prerequisite in many clinical modeling applications is the ability of models to faithfully replicate potential maps and electrograms recorded from a given patient. However, while the personalization of electrophysiology models based on the gold standard bidomain formulation is in principle feasible, the associated computational expenses are significant, rendering their use incompatible with clinical time frames. In this study we report on the development of a novel computationally efficient reaction-eikonal (R-E) model for modeling extracellular potential maps and electrograms. Using a biventricular human electrophysiology model, which incorporates a topologically realistic His–Purkinje system (HPS), we demonstrate by comparing against a high-resolution reaction–diffusion (R–D) bidomain model that the R-E model predicts extracellular potential fields, electrograms as well as ECGs at the body surface with high fidelity and offers vast computational savings greater than three orders of magnitude. Due to their efficiency R-E models are ideally suitable for forward simulations in clinical modeling studies which attempt to personalize electrophysiological model features. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
11. Evaluation of a Rapid Anisotropic Model for ECG Simulation.
- Author
-
Pezzuto, Simone, Kal'avský, Peter, Potse, Mark, Prinzen, Frits W., Auricchio, Angelo, and Krause, Rolf
- Subjects
ANISOTROPY ,ELECTROCARDIOGRAPHY ,SIMULATION methods & models ,ELECTRIC conductivity ,MYOCARDIUM - Abstract
State-of-the-art cardiac electrophysiology models that are able to deliver physiologically motivated activation maps and electrocardiograms (ECGs) can only be solved on high-performance computing architectures. This makes it nearly impossible to adopt such models in clinical practice. ECG imaging tools typically rely on simplified models, but these neglect the anisotropic electric conductivity of the tissue in the forward problem. Moreover, their results are often confined to the heart-torso interface. We propose a Forward model that fully accounts for the anisotropic tissue conductivity and produces the standard 12-lead ECG in a few seconds. The activation sequence is approximated with an eikonal model in the 3d myocardium, while the ECG is computed with the lead-field approach. Both solvers were implemented on graphics processing units and massively parallelized. We studied the numerical convergence and scalability of the approach. We also compared the method to the bidomain model in terms of ECGs and activation maps, using a simplified but physiologically motivated geometry and 6 patient-specific anatomies. The proposed methods provided a good approximation of activation maps and ECGs computed with a bidomain model, in only a few seconds. Both solvers scaled very well to high-end hardware. These methods are suitable for use in ECG imaging methods, and may soon become fast enough for use in interactive simulation tools. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
12. Refining the Eikonal Model to Reproduce the Influence of Atrial Tissue Geometry on Conduction Velocity
- Author
-
Nils Skupien, Cristian Barrios Espinosa, Olaf Dössel, and Axel Loewe
- Subjects
conduction velocity ,eikonal model ,Biomedical Engineering ,tissue curvature ,atrial fibrillation ,wall thickness ,ddc:620 ,cardiac modelling ,Engineering & allied operations - Abstract
Atrial fibrillation is responsible for a significant and steadily rising burden. Simultaneously, the treatment options for atrial fibrillation are far from optimal. Personalized simulations of cardiac electrophysiology could assist clinicians in the risk stratification and therapy planning for atrial fibrillation. However, the use of personalized simulations in clinics is currently not possible due to either too high computational costs or non-sufficient accuracy. Eikonal simulations come with low computational costs but cannot replicate the influence of cardiac tissue geometry on the conduction velocity of the wave propagation. Consequently, they currently lack the required accuracy to be applied in clinics. Biophysically detailed simulations on the other hand are accurate but associated with too high computational costs. To tackle this issue, a regression model is created based on biophysically detailed bidomain simulation data. This regression formula calculates the conduction velocity dependent on the thickness and curvature of the heart wall. Afterwards the formula was implemented into the eikonal model with the goal to increase the accuracy of the eikonal model without losing its advantage of computational efficiency. The results of the modified eikonal simulations demonstrate that (i) the local activation times become significantly closer to those of the biophysically detailed bidomain simulations, (ii) the advantage of the eikonal model of a low sensitivity to the resolution of the mesh was reduced further, and (iii) the unrealistic occurrence of endo-epicardial dissociation in simulations was remedied. The results suggest that the accuracy of the eikonal model was significantly increased. At the same time, the additional computational costs caused by the implementation of the regression formula are neglectable. In conclusion, a successful step towards a more accurate and fast computational model of cardiac electrophysiology was achieved.
- Published
- 2022
13. A fast cardiac electromechanics model coupling the Eikonal and the nonlinear mechanics equations
- Author
-
Simone Stella, Francesco Regazzoni, Christian Vergara, Luca Dedé, and Alfio Quarteroni
- Subjects
algorithm ,monodomain ,Applied Mathematics ,contraction ,excitation ,tissue ,Cardiac electromechanics ,heart ,numerical simulations ,generation ,Modeling and Simulation ,Eikonal model ,propagation ,PV loops ,myocardium ,activation - Abstract
We present a new model of human cardiac electromechanics for the left ventricle where electrophysiology is described by a Reaction–Eikonal model and which enables an off-line resolution of the reaction model, thus entailing a big saving of computational time. Subcellular dynamics is coupled with a model of tissue mechanics, which is in turn coupled with a Windkessel model for blood circulation. Our numerical results show that the proposed model is able to provide a physiological response to changes in certain variables (end-diastolic volume, total peripheral resistance, contractility). We also show that our model is able to reproduce with high accuracy and with a considerably lower computational time the results that we would obtain if the monodomain model should be used in place of the Eikonal model.
- Published
- 2022
14. Excitation function of elastic pp scattering from a unitarily extended Bialas-Bzdak model.
- Author
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Nemes, F., Csörgő, T., and Csanád, M.
- Subjects
- *
POLYPROPYLENE , *ELASTIC scattering , *PROTON-proton cycle , *NUCLEAR excitation , *PARAMETERS (Statistics) - Abstract
The Bialas-Bzdak model of elastic proton-proton scattering assumes a purely imaginary forward scattering amplitude, which consequently vanishes at the diffractive minima. We extended the model to arbitrarily large real parts in a way that constraints from unitarity are satisfied. The resulting model is able to describe elastic pp scattering not only at the lower ISR energies but also at in a statistically acceptable manner, both in the diffractive cone and in the region of the first diffractive minimum. The total cross-section as well as the differential cross-section of elastic proton-proton scattering is predicted for the future LHC energies of , 14, 15 TeV and also to 28 TeV. A nontrivial, significantly nonexponential feature of the differential cross-section of elastic proton-proton scattering is analyzed and the excitation function of the nonexponential behavior is predicted. The excitation function of the shadow profiles is discussed and related to saturation at small impact parameters. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
15. Using the Eikonal Model of Spectral Albedo of Rough Space Object Coatings for Solving a Direct Photometry Problem.
- Author
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Murtazov, A.
- Subjects
- *
LIGHT scattering , *EIKONAL equation , *DIFFERENTIAL equations , *ALBEDO , *ASTRONOMICAL photometry , *SPECTROPHOTOMETRY - Abstract
Light scattering by a random rough isotropic surface is considered in the eikonal approximation. A model for accounting of mutual shading of surface elements at large incidence and observation angles is proposed. On the basis of this model, the optical parameters of space object coatings are estimated by the methods of nonlinear regression analysis. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
16. ELASTIC SCATTERING OF PROTONS FROM to 7 TeV FROM A GENERALIZED BIALAS-BZDAK MODEL.
- Author
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CSÖRGŐ, T. and NEMES, F.
- Subjects
- *
ELASTIC scattering , *GENERALIZATION , *PROTON-proton interactions , *CROSS-sectional method , *QUARKS , *LARGE Hadron Collider - Abstract
The Bialas-Bzdak model of elastic proton-proton scattering is generalized to the case when the real part of the parton-parton level forward scattering amplitude is nonvanishing. Such a generalization enables the model to describe well the dip region of the differential cross-section of elastic scattering at the intersecting storage rings (ISR) energies, and improves significantly the ability of the model to describe also the recent TOTEM data at LHC energy. Within this framework, both the increase of the total cross-section, as well as the decrease of the location of the dip with increasing colliding energies, is related to the increase of the quark-diquark distance and to the increase of the "fragility" of the protons with increasing energies. In addition, we present and test the validity of two new phenomenological relations: one of them relates the total p+p cross-section to an effective, model-independent proton radius, while the other relates the position of the dip in the differential elastic cross-section to the measured value of the total cross-section. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
17. Reliable extraction of the dB(E1)/dE for 11Be from its breakup at 520 MeV/nucleon
- Author
-
Moschini, Laura, Capel, Pierre, Moschini, Laura, and Capel, Pierre
- Abstract
We analyze the breakup of the one-neutron halo nucleus 11Be measured at 520 MeV/nucleon at GSI on Pb and C targets within an eikonal description of the reaction including a proper treatment of special relativity. The Coulomb term of the projectile-target interaction is corrected at first order, while its nuclear part is described at the optical limit approximation. Good agreement with the data is obtained using a description of 11Be, which fits the breakup data of RIKEN. This solves the apparent discrepancy between the dB(E1)/dE estimations from GSI and RIKEN for this nucleus., SCOPUS: ar.j, info:eu-repo/semantics/published
- Published
- 2019
18. Structure of 33Mg sheds new light on the island of inversion
- Author
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Kanungo, R., Nociforo, C., Prochazka, A., Utsuno, Y., Aumann, T., Boutin, D., Cortina-Gil, D., Davids, B., Diakaki, M., Farinon, F., Geissel, H., Gernhäuser, R., Gerl, J., Janik, R., Jonson, B., Kindler, B., Knöbel, R., Krücken, R., Lantz, M., and Lenske, H.
- Subjects
- *
NUCLEAR structure , *MAGNESIUM isotopes , *SPECTRUM analysis , *MOMENTUM distributions , *NUCLEAR reactions , *NEUTRON cross sections , *NUCLEAR shell theory - Abstract
Abstract: The first reaction spectroscopy on the ground state structure of 33Mg through the measurement of the longitudinal momentum distribution from the one-neutron removal reaction using a C target at is reported. The experiment was performed at the FRS, GSI. The distribution has a relatively narrow width ( (FWHM)) and the one-neutron removal cross-section is . An increased contribution from the orbital is required to explain the observation showing its lowering compared to existing model predictions. This provides new information regarding the configuration of 33Mg and the island of inversion. [Copyright &y& Elsevier]
- Published
- 2010
- Full Text
- View/download PDF
19. FORWARD PHYSICS AT THE LHC:: ELASTIC SCATTERING.
- Author
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Fiore, R., Jenkovszky, L., Orava, R., Predazzi, E., Produkin, A., and Selyugin, O.
- Subjects
- *
ELASTIC scattering , *ELASTIC cross sections , *LARGE Hadron Collider , *POMERONS , *REGGE trajectories , *QUANTUM chromodynamics , *EXTRAPOLATION - Abstract
The following effects in the nearly forward ("soft") region of the LHC are proposed to be investigated: • At small |t| the fine structure of the cone (Pomeron) should be scrutinized: (a) a break of the cone near t ≈ -0.1 GeV2, due to the two-pion threshold, and required by t-channel unitarity, and (b) possible small-period oscillations between t = 0 and the dip region. • In measuring the elastic pp scattering and total pp cross-section at the LHC, the experimentalists are urged to treat the total cross-section σt, the ratio ρ of real to imaginary part of the forward scattering amplitude, the forward slope B and the luminosity ${\mathcal L}$ as free parameters, and to publish model-independent results on dN/dt. • Of extreme interest are the details of the expected diffraction minimum in the differential cross-section. Its position, expected in the interval 0.4 < -t < 1 GeV2 at the level of about 10-2mb · GeV-2–10-1mb · GeV-2, cannot be predicted unambiguously, and its depth, i.e. the ratio of dσ/dt at the minimum to that at the subsequent maximum (about -t = 5 GeV2, which is about 5) is of great importance. • The expected slow-down with increasing |t| of the shrinkage of the second cone (beyond the dip-bump), together with the transition from an exponential to a power decrease in -t, will be indicative of the transition from "soft" to "hard" physics. Explicit models are proposed to help in quantifying this transition. • In a number of papers a limiting behavior, or saturation of the black disk limit (BDL), was predicted. This controversial phenomenon shows that the BDL may not be the ultimate limit, instead a transition from shadow to antishadow scattering may by typical of the LHC energy scale. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
20. COULOMB-MODIFIED EIKONAL PHASE SHIFT ANALYSIS BASED ON HYPERBOLIC TRAJECTORY FOR 12C + 12C ELASTIC SCATTERINGS.
- Author
-
KIM, YONG JOO and CHA, MOON HOE
- Subjects
- *
HYPERBOLIC spaces , *SPACE trajectories , *ELASTIC scattering , *NUCLEAR activation analysis , *CATHODE ray tube deflection systems , *FLUCTUATIONS (Physics) - Abstract
We present a Coulomb-modified eikonal model formalism based on hyperbolic trajectory for heavy-ion elastic scattering. This formalism has been applied satisfactorily to elastic scatterings of the 12C + 12C system at Elab=240, 360 and 1016 MeV. The presence of a nuclear rainbow in this system is evidenced through a classical deflection function. The Fraunhöfer oscillations observed in the elastic angular distributions can be explained due to interference between the near- and far-side amplitudes. We have found that the hyperbolic trajectory effect on the eikonal model is important when the absorptive potential is weak and the real potential is strong. [ABSTRACT FROM AUTHOR]
- Published
- 2004
- Full Text
- View/download PDF
21. Reliable extraction of the dB(E1)/dE for 11Be from its breakup at 520 MeV/nucleon
- Author
-
Pierre Capel and Laura Moschini
- Subjects
Nuclear and High Energy Physics ,Relativistic correction ,Nuclear Theory ,FOS: Physical sciences ,Halo nucleus ,Special relativity ,One-neutron halo nuclei ,dB(E1)/dE ,Nuclear breakup ,01 natural sciences ,Nuclear physics ,Nuclear Theory (nucl-th) ,Eikonal model ,0103 physical sciences ,Coulomb ,medicine ,Coulomb breakup ,010306 general physics ,Nuclear Experiment ,Physics ,010308 nuclear & particles physics ,Eikonal equation ,Breakup ,Physique atomique et nucléaire ,lcsh:QC1-999 ,medicine.anatomical_structure ,Proper treatment ,Physics::Accelerator Physics ,Nucleon ,Nucleus ,lcsh:Physics - Abstract
We analyze the breakup of the one-neutron halo nucleus 11Be measured at 520 MeV/nucleon at GSI on Pb and C targets within an eikonal description of the reaction including a proper treatment of special relativity. The Coulomb term of the projectile-target interaction is corrected at first order, while its nuclear part is described at the optical limit approximation. Good agreement with the data is obtained using a description of 11Be, which fits the breakup data of RIKEN. This solves the apparent discrepancy between the dB(E1)/dE estimations from GSI and RIKEN for this nucleus., SCOPUS: ar.j, info:eu-repo/semantics/published
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- 2019
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22. Parametrization of activation based cardiac electrophysiology models using bidomain model simulations
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Birgit Stender
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Physics ,medicine.medical_specialty ,Cardiac electrophysiology ,Quantitative Biology::Tissues and Organs ,0206 medical engineering ,lcsh:R ,Biomedical Engineering ,Bidomain model ,lcsh:Medicine ,02 engineering and technology ,020601 biomedical engineering ,bidomain model ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,conduction velocity ,0302 clinical medicine ,Classical mechanics ,monodomain model ,eikonal model ,Internal medicine ,medicine ,Cardiology ,Monodomain model ,Parametrization ,cardiac electrophysiology - Abstract
Eikonal models are useful to compute approximate solutions of cardiac excitation propagation in a computationally efficient way. In this work the underlying conduction velocities for different cell types were computed solving the classical bidomain model equations for planar wavefront propagation. It was further investigated how changes in the conductivity tensors within the bidomain model analytically correspond to changes in the conduction velocity. The error in the presence of local front curvature for the derived eikonal model parametrization were analyzed. The conduction velocity simulated based on the bidomain model was overestimated by a maximum of 10%.
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- 2016
23. Spread of Excitation in a Myocardial Volume: Simulation Studies in a Model of Anisotropic Ventricular Muscle Activated by Point Stimulation.
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Franzone, Piero Colli, Guerri, Luciano, and Taccardi, Bruno
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ENDOTHELIUM ,MYOCARDIAL infarction ,CORONARY disease ,ENDOCARDIUM ,EPITHELIUM ,HEART - Abstract
Introduction: The purpose of this study was to present simulations of excitation wavefronts spreading through a parallelepipedal slab of ventricular tissue measuring 6.5 × 6.5 × 1.0 cm. Methods and Results: The slab incorporates the anisotropic properties of the myocardium including the transmural counterclockwise fiber rotation from epicardium to endocardium. Simulations were based on an eikonal model that determines excitation times throughout the ventricular wall, which is represented as an anisotropic bidomain. Excitation was initiated by delivering ectopic stimuli at various intramural depths. We also investigated the effect of a simplified Purkinje network on excitation patterns. Excitation wavefronts in the plane of pacing, parallel to epicardial-endocardial surfaces, were oblong with the major axis approximately oriented along the local fiber direction, with bulges and deformations due to attraction from rotating fibers in adjacent planes. The oblong intersections of the wavefront with planes at increasing distance from pacing plane rotated clockwise or counterclockwise, depending on pacing depth, but wavefront rotation was always less than fiber rotation in the same plane. For all pacing depths, excitation returned toward the plane of pacing. Return occurred in multiple, varying sectors of the slab depending on pacing depth, and was observed as close as 6 mm to the pacing site. Conclusion: Curvature of wavefronts and collision with boundaries of slab markedly affected local velocities. Shape and separation of epicardial isochrones and spatial distribution of epicardial velocities varied as a function of site and depth of pacing. When the Purkinje network was added to the model, epicardial velocities revealed the subendocardial location of the Purkinje-myocardial junctions. Considerable insight into intramural events could be obtained from epicardial isochrones. If validated experimentally, results may be applicable to epicardial isochrones recorded at surgery. [ABSTRACT FROM AUTHOR]
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- 1993
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24. Modeling ventricular excitation: axial and orthotropic anisotropy effects on wavefronts and potentials
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Colli-Franzone, Piero, Guerri, Luciano, and Taccardi, Bruno
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- *
EIKONAL equation , *EXCITATION (Physiology) , *ELECTRONOGRAPHY - Abstract
By applying the eikonal approximation to the bidomain model of the cardiac tissue we investigate the influence of the axially isotropic and orthotropic conductivity tensors on the propagation of the excitation wavefronts and on the associated potential distribution and electrograms. [Copyright &y& Elsevier]
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- 2004
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25. Efficient computation of electrograms and ECGs in human whole heart simulations using a reaction-eikonal model
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Gernot Plank, Martin J. Bishop, Steven A. Niederer, Aurel Neic, Anton J. Prassl, Fernando O. Campos, Edward J. Vigmond, Medical University Graz, Deutsches Herzzentrum Berlin, King‘s College London, Modélisation et calculs pour l'électrophysiologie cardiaque (CARMEN), Institut de Mathématiques de Bordeaux (IMB), Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Inria Bordeaux - Sud-Ouest, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-IHU-LIRYC, CHU Bordeaux [Bordeaux]-Université Bordeaux Segalen - Bordeaux 2-CHU Bordeaux [Bordeaux], Karl-Franzens-Universität [Graz, Autriche], Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Inria Bordeaux - Sud-Ouest, Université Bordeaux Segalen - Bordeaux 2-CHU Bordeaux [Bordeaux]-CHU Bordeaux [Bordeaux], and Karl-Franzens-Universität Graz
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Physics and Astronomy (miscellaneous) ,Computer science ,Computation ,0206 medical engineering ,Cardiac electrophysiology ,Electrical activation and repolarization ,02 engineering and technology ,030204 cardiovascular system & hematology ,Machine learning ,computer.software_genre ,Article ,Rendering (computer graphics) ,Personalization ,03 medical and health sciences ,0302 clinical medicine ,High fidelity ,[SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system ,Eikonal model ,Numerical Analysis ,Modality (human–computer interaction) ,business.industry ,Eikonal equation ,Applied Mathematics ,Perspective (graphical) ,Bidomain model ,020601 biomedical engineering ,Computer Science Applications ,Computational Mathematics ,Modeling and Simulation ,[SDV.IB]Life Sciences [q-bio]/Bioengineering ,Artificial intelligence ,business ,computer - Abstract
International audience; Anatomically accurate and biophysically detailed bidomain models of the human heart have proven a powerful tool for gaining quantitative insight into the links between electrical sources in the myocardium and the concomitant current flow in the surrounding medium as they represent their relationship mechanistically based on first principles. Such models are increasingly considered as a clinical research tool with the perspective of being used, ultimately, as a complementary diagnostic modality. An important prerequisite in many clinical modeling applications is the ability of models to faithfully replicate potential maps and electrograms recorded from a given patient. However, while the personalization of electrophysiology models based on the gold standard bidomain formulation is in principle feasible, the associated computational expenses are significant, rendering their use incompatible with clinical time frames. In this study we report on the development of a novel computationally efficient reaction-eikonal (R-E) model for modeling extracellular potential maps and electrograms. Using a biventricular human electrophysiology model, which incorporates a topologically realistic His-Purkinje system (HPS), we demonstrate by comparing against a high-resolution reaction-diffusion (R-D) bidomain model that the R-E model predicts extracellular potential fields, electrograms as well as ECGs at the body surface with high fidelity and offers vast computational savings greater than three orders of magnitude. Due to their efficiency R-E models are ideally suitable for forward simulations in clinical modeling studies which attempt to personalize electrophysiological model features.
- Published
- 2017
26. Models of Elastic pp Scattering at High Energies – Possibilities, Limitations, Assumptions, and Open Ques-tions
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J. Procházka, V. Kundrát, and M. V. Lokajíček
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010302 applied physics ,Physics ,Scattering ,General Physics and Astronomy ,elastic scattering of hadrons ,01 natural sciences ,Theoretical physics ,eikonal model ,0103 physical sciences ,WY approach ,proton-proton collisions ,impact parameter ,010306 general physics ,Coulomb-hadronic interference ,central or peripheral scattering - Abstract
The simplest collision process, the elastic scattering of protons, has been measured at various energies and in a broad interval of scattering angles. Its theoretical description is, however, much more delicate, than it may seem at first glance. The widely used eikonal model allowed one to analyze the pp elastic scattering data at an ISR energy of 52.8 GeV and the TOTEM data at a much higher LHC energy of 8 TeV. The results represent the most detailed elaborated impact parameter analysis of pp data which has ever been performed. They have helped to identify several deeper open questions and problems concerning all widely used theoretical frameworks used for the description of the elastic pp scattering. The problems should be further studied and solved to derive some important proton characteristics which may be obtained with the help of the elastic scattering., Найпростiший процес зiткнень, а саме пружне розсiяння протонiв вимiрювалось при рiзних енергiях та широкому iнтервалi кутiв розсiяння. Вiдповiдний теоретичний опис, однак, набагато делiкатнiший, нiж може здаватися. Широко вiдома ейкональна модель дозволила провести аналiз пружних pp-даних при енергiях прискорювачiв ISR, 52,8 ГеВ та LHC 8 ТеВ. Нашi результати представляють найдетальнiший та ретельно опрацьований прицiльний аналiз pp-даних. Вони допомогли прояснити ряд питань та проблем опису пружного розсiяння протонiв. Цю програму потрiбно продовжити.
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- 2019
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27. Reconstruction of three-dimensional biventricular activation based on the 12-lead electrocardiogram via patient-specific modelling.
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Pezzuto S, Prinzen FW, Potse M, Maffessanti F, Regoli F, Caputo ML, Conte G, Krause R, and Auricchio A
- Subjects
- Body Surface Potential Mapping, Heart Ventricles diagnostic imaging, Humans, Magnetic Resonance Imaging, Electrocardiography, Patient-Specific Modeling
- Abstract
Aims: Non-invasive imaging of electrical activation requires high-density body surface potential mapping. The nine electrodes of the 12-lead electrocardiogram (ECG) are insufficient for a reliable reconstruction with standard inverse methods. Patient-specific modelling may offer an alternative route to physiologically constraint the reconstruction. The aim of the study was to assess the feasibility of reconstructing the fully 3D electrical activation map of the ventricles from the 12-lead ECG and cardiovascular magnetic resonance (CMR)., Methods and Results: Ventricular activation was estimated by iteratively optimizing the parameters (conduction velocity and sites of earliest activation) of a patient-specific model to fit the simulated to the recorded ECG. Chest and cardiac anatomy of 11 patients (QRS duration 126-180 ms, documented scar in two) were segmented from CMR images. Scar presence was assessed by magnetic resonance (MR) contrast enhancement. Activation sequences were modelled with a physiologically based propagation model and ECGs with lead field theory. Validation was performed by comparing reconstructed activation maps with those acquired by invasive electroanatomical mapping of coronary sinus/veins (CS) and right ventricular (RV) and left ventricular (LV) endocardium. The QRS complex was correctly reproduced by the model (Pearson's correlation r = 0.923). Reconstructions accurately located the earliest and latest activated LV regions (median barycentre distance 8.2 mm, IQR 8.8 mm). Correlation of simulated with recorded activation time was very good at LV endocardium (r = 0.83) and good at CS (r = 0.68) and RV endocardium (r = 0.58)., Conclusion: Non-invasive assessment of biventricular 3D activation using the 12-lead ECG and MR imaging is feasible. Potential applications include patient-specific modelling and pre-/per-procedural evaluation of ventricular activation., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Society of Cardiology.)
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- 2021
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28. The eikonal model for regge cuts in pion-nucleon scattering
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Collins, P. D. B., Gault, F. D., Höhler, Gerhard, Fujimori, Atsushi, Kühn, Johann, Müller, Thomas, Steiner, Frank, Stwalley, William C., Trümper, Joachim E., Wölfle, Peter, and Woggon, Ulrike
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- 1972
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29. Eikonal model analysis of 240 MeV 6Li elastic scattering on 24Mg and 28Si
- Author
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Kim, Yong Joo, Woo, Jong-Kwan, and Lee, Seok Jae
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- 2012
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30. Structure of 33Mg sheds new light on the island of inversion
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Kanungo, R., Nociforo, C., Prochazka, A., Utsuno, Y., Aumann, T., Boutin, D., Cortina-Gil, D., Davids, B., Diakaki, M., Farinon, F., Geissel, H., Gernhäuser, R., Gerl, J., Janik, R., Jonson, B., Kindler, B., Knöbel, R., Krücken, R., Lantz, Mattias, Lenske, H., Litvinov, Y., Mahata, K., Maierbeck, P., Musumarra, A., Nilsson, T., Otsuka, T., Perro, C., Scheidenberger, C., Sitar, B., Strmen, P., Sun, B., Szarka, I., Tanihata, I., Weick, H., Winkler, M., Kanungo, R., Nociforo, C., Prochazka, A., Utsuno, Y., Aumann, T., Boutin, D., Cortina-Gil, D., Davids, B., Diakaki, M., Farinon, F., Geissel, H., Gernhäuser, R., Gerl, J., Janik, R., Jonson, B., Kindler, B., Knöbel, R., Krücken, R., Lantz, Mattias, Lenske, H., Litvinov, Y., Mahata, K., Maierbeck, P., Musumarra, A., Nilsson, T., Otsuka, T., Perro, C., Scheidenberger, C., Sitar, B., Strmen, P., Sun, B., Szarka, I., Tanihata, I., Weick, H., and Winkler, M.
- Abstract
The first reaction spectroscopy on the ground state structure of 33Mg through the measurement ofthe longitudinal momentum distribution from the one-neutron removal reaction using a C target at 898 A MeV is reported. The experiment was performed at the FRS, GSI. The distribution has a relativelynarrow width (150 ± 3 MeV/c (FWHM)) and the one-neutron removal cross-section is 74 ± 4 mb. An in-creased contribution from the 2p3/2 orbital is required to explain the observation showing its loweringcompared to existing model predictions. This provides new information regarding the configuration of 33Mg and the island of inversion.
- Published
- 2010
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31. Structure of 33Mg sheds new light on the N=20 island of inversion
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Thomas Nilsson, A. Musumarra, A. Prochazka, C. Nociforo, Imrich Szarka, Mattias Lantz, R. Knöbel, Hans Geissel, Yutaka Utsuno, P. Maierbeck, C. Perro, K. Mahata, Horst Lenske, Helmut Weick, Barry Davids, Takaharu Otsuka, D. Boutin, D. Cortina-Gil, Birgit Kindler, M. Winkler, Thomas Aumann, Roman Gernhäuser, Peter Strmen, C. Scheidenberger, R. Janik, M. Diakaki, Björn Jonson, R. Krücken, Bao-Hua Sun, J. Gerl, Y. Litvinov, Isao Tanihata, Rituparna Kanungo, Branislav Sitar, and F. Farinon
- Subjects
Physics ,Nuclear reaction ,Nuclear and High Energy Physics ,Nucleon removal or knockout reactions ,010308 nuclear & particles physics ,Island of inversion ,01 natural sciences ,Shell structure ,Baryon ,Full width at half maximum ,Eikonal model ,0103 physical sciences ,Atomic physics ,010306 general physics ,Ground state ,Nucleon ,Spectroscopy ,Nuclear Experiment ,Isotopes of magnesium ,Magic number ,Radioactive beams - Abstract
The first reaction spectroscopy on the ground state structure of 33 Mg through the measurement of the longitudinal momentum distribution from the one-neutron removal reaction using a C target at 898 A MeV is reported. The experiment was performed at the FRS, GSI. The distribution has a relatively narrow width (150 ± 3MeV / c (FWHM)) and the one-neutron removal cross-section is 74 ± 4mb.Anin- creased contribution from the 2 p 3 / 2 orbital is required to explain the observation showing its lowering compared to existing model predictions. This provides new information regarding the configuration of 33 Mg and the island of inversion. ispartof: Physics Letters B vol:685 issue:4 pages:253-257 status: published
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32. Spiral Waves Generation Using an Eikonal-Reaction Cardiac Electrophysiology Model
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Yves Coudière, Nejib Zemzemi, Narimane Gassa, Cesare Corrado, Modélisation et calculs pour l'électrophysiologie cardiaque (CARMEN), Institut de Mathématiques de Bordeaux (IMB), Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Inria Bordeaux - Sud-Ouest, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-IHU-LIRYC, Université Bordeaux Segalen - Bordeaux 2-CHU Bordeaux [Bordeaux]-CHU Bordeaux [Bordeaux], King‘s College London, This Project has received funding from the European Unions Horizon research and innovation programme under the Marie Skłodowska-Curie grant agreement N° 860974 and by the French National Research Agency, grant references ANR-10-IAHU04- LIRYC and ANR-11-EQPX-0030., ANR-10-IAHU-0004,LIRYC,L'Institut de Rythmologie et modélisation Cardiaque(2010), ANR-11-EQPX-0030,MUSIC,Plateforme multi-modale d'exploration en cardiologie(2011), European Project: 860974,PersonalizeAF(2020), and Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Université Bordeaux Segalen - Bordeaux 2-Université Sciences et Technologies - Bordeaux 1 (UB)-Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux (Bordeaux INP)-Centre National de la Recherche Scientifique (CNRS)-Inria Bordeaux - Sud-Ouest
- Subjects
0303 health sciences ,Work (thermodynamics) ,Eikonal equation ,Computer science ,Cardiac electrophysiology ,Mechanics ,030204 cardiovascular system & hematology ,Model complexity ,Atrial fibrillation ,[INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation ,03 medical and health sciences ,0302 clinical medicine ,Spiral wave ,Eikonal model ,Spiral Wave ,Diffusion current ,Cardiac Electrophysiology ,Monodomain model ,Spiral ,030304 developmental biology - Abstract
Aim: Computer models enabled the study of the fundamental mechanisms responsible for arrhythmias and have the potential of optimizing the clinical procedure for an individual patients pathology. The model complexity and the computational costs affecting computer models hamper their application on a routinely performed procedure. In this work, we aim to design a computer model suitable for clinical time scales. Methods: We adopt a (multi-front) eikonal model that adapts the conduction velocity to the underlying electrophysiology; we describe the diffusion current using a parametrised form, fitted to reproduce the monodomain profile. Results: We simulated spiral waves on a 3D tissue slab and bi-atrial anatomy. We compared the numerical results obtained with a monodomain formulation with those obtained with the new method. Both models provided the same pattern of the spiral waves. While the monodomain model presented slower propagation fronts, the eikonal model captured the correct value of the conduction velocity CV even using a coarse resolution. Conclusion: The eikonal model has the potential of enabling computer-guided procedures when adapts the conduction velocity to the underlying electrophysiology and characterises the diffusion current with a parametrised form.
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