Article
Engineering, Biomedical
Meng Xiao, Jinlin Wu, Duanduan Chen, Chenghu Wang, Yanfen Wu, Tucheng Sun, Jie Chen
Summary: This study used fluid-structure interaction analysis to investigate the relationship between morphological parameters and hemodynamic conditions in ascending aortic aneurysms. The results suggest that enlarged ascending aortic volume is associated with compromised hemodynamic conditions and higher mechanical wall stress.
ACTA BIOMATERIALIA
(2023)
Article
Engineering, Multidisciplinary
Henry von Wahl, Thomas Wick
Summary: This work studied the interaction between a Stokes flow in a deformable fracture and a linear elastic medium. The crack dynamics were approximated using a phase-field model, which captures the interface by a smeared zone. The main objective was to construct a robust framework that first computes the crack path using the phase-field method and then does an interface-tracking reconstruction. Various approaches for reconstructing the open crack domain were discussed, including unfitted approaches and remeshing. Numerical examples based on Sneddon's benchmark were used to substantiate the approach.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Biology
Talha Lone, Angelica Alday, Rana Zakerzadeh
Summary: Supravalvular aortic stenosis is a type of aortic malformation characterized by narrowing of the ascending aorta. Pressure measurements from Doppler ultrasound exams are often higher than invasive cardiac catheterization, leading to potentially premature surgical treatment decisions. A computational model was developed to accurately predict pressure drop across the stenotic region, highlighting significant discrepancies in SVAS assessment methods.
COMPUTERS IN BIOLOGY AND MEDICINE
(2021)
Article
Computer Science, Interdisciplinary Applications
David R. Wells, Ben Vadala-Roth, Jae H. Lee, Boyce E. Griffith
Summary: The IFED method is a computational approach for modeling fluid-structure interactions using finite element and finite difference techniques. This paper presents numerical and computational analyses of the effects of replacing the projection matrices in the force projection and IFED coupling operators with diagonal approximations. The results show that lumped mass matrices derived from nodal quadrature rules can be used with the IFED method, unlike standard FE methods.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Mathematics, Applied
Harshin Kamal Asok
Summary: This article presents a locally modified parametric finite element method for fluid structure interaction problems using LBB-stable finite elements. The method solves the variational formulation of the coupled fluid structure interaction problems using a fully Eulerian framework and approximates globally defined velocity-displacement-pressure fields with specific finite elements. The numerical simulation results of the new framework show good agreement with benchmark data and the framework is also extended for adaptive grid refinement.
APPLIED NUMERICAL MATHEMATICS
(2021)
Article
Mathematical & Computational Biology
Li Cai, Yu Hao, Pengfei Ma, Guangyu Zhu, Xiaoyu Luo, Hao Gao
Summary: This paper studies the mechanics of aortic valve caused by calcification and uses a numerical model to investigate the dynamics and hemodynamic performance of the valve under normal and calcified conditions. The results show that calcification significantly affects the motion and blood flow of the valve, potentially leading to ventricular dysfunction.
MATHEMATICAL BIOSCIENCES AND ENGINEERING
(2022)
Article
Engineering, Multidisciplinary
Caili Li, Dalin Tang, Jing Yao, Christopher Baird, Haoliang Sun, Chanjuan Gong, Luyao Ma, Yanjuan Zhang, Liang Wang, Han Yu, Chun Yang, Yongfeng Shao
Summary: The study showed that larger valves resulted in lower transvalvular pressure gradient, potentially improving post-AVR outcomes. Implanting larger valves can significantly reduce mean flow shear stress on valve leaflets, which may lead to enhanced hemodynamic performance and valve cardiac function post AVR.
CMES-COMPUTER MODELING IN ENGINEERING & SCIENCES
(2021)
Article
Computer Science, Interdisciplinary Applications
Julien Vanharen, Adrien Loseille, Frederic Alauzet
Summary: A new strategy for high-fidelity unsteady mesh adaptation dealing with fluid-structure interaction problems is introduced, using a partitioned approach to solve the Euler and linear elasticity equations through Finite-Volume and finite-element methods, respectively. The coupling between the codes is achieved by imposing suitable boundary conditions on conforming meshes, even at the fluid-structure interface, assuming small displacements of the structure without deforming the mesh. The unsteady mesh adaptation process is based on a cavity operator capable of handling non-manifold geometry and is validated through two-dimensional and three-dimensional test cases.
ENGINEERING WITH COMPUTERS
(2022)
Article
Engineering, Multidisciplinary
Narendra S. Nanal, Scott T. Miller, Jesse D. Thomas, Lucy T. Zhang
Summary: This study presents a computational framework for simulating shell structures interacting with fluids using the immersed approach. The approach captures the complex movement and motion of thin structures and allows non-intrusive coupling of independent fluid and shell finite element solvers. The method projects the shell structure to create a volumetric structure, enabling accurate and realistic loading and geometry.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Engineering, Biomedical
Hugo L. Oliveira, Gustavo C. Buscaglia, Rodrigo R. Paz, Facundo Del Pin, Jose A. Cuminato, Monica Kerr, Sean Mckee, Iain W. Stewart, David J. Wheatley
Summary: Valvular heart diseases are major contributors to global deaths and disability. This study presents an innovative design for prosthetic aortic valves and develops a numerical model to understand their mechanical behavior and failure modes. The results show that the numerical model can accurately reproduce experimental data.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING
(2023)
Article
Engineering, Geological
Conrado S. Guerra, Josue Labaki, Persio L. A. Barros
Summary: This article proposes a novel numerical model for the dynamic response of large diameter, concrete-lined circular shafts embedded in transversely isotropic soils. The model accurately represents the energy exchange between the shaft and soil, as well as the energy propagation through the soil.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2022)
Article
Computer Science, Interdisciplinary Applications
Nimmy Thankom Philip, B. S. Patnaik, B. J. Sudhir
Summary: This study investigates the hemodynamic and bio-mechanical changes occurring during the growth stages of abdominal aortic aneurysms (AAA) using fluid structure interaction (FSI) studies. The results show that abnormal low wall shear stress (WSS) areas and high/low oscillatory shear index (OSI) areas increase at different rates for shorter and longer aneurysms as the diameter progresses. Drastic increase in maximum wall stresses (MWS) and wall displacement were observed as the aneurysm approaches the critical diameter. The hemodynamic predictors are highly dependent on the shape index (DHr) when the aneurysm is small, while the wall stresses are influenced significantly by DHr as the aneurysm approaches the critical diameter. Routine monitoring of shorter aneurysms (high DHr) at different growth stages is necessary to prevent unexpected rupture.
COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE
(2022)
Article
Engineering, Biomedical
Dan Lior, Charles Puelz, Colin Edwards, Silvana Molossi, Boyce E. Griffith, Ravi K. Birla, Craig G. Rusin
Summary: This paper presents a semi-automatic method for constructing volumetric models of the aortic valve using computed tomography angiography images. The method uses manually selected samples of the aortic segmentation derived from the images to inform the model construction. Valve models for pediatric patients are created and simulation results show that the method produces functional valves that generate pressure and flow waveforms similar to clinical observations.
ANNALS OF BIOMEDICAL ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Jeannette Hiromi Spuhler, Johan Hoffman
Summary: An interface tracking finite element methodology is proposed for 3D turbulent flow fluid-structure interaction, with a specific focus on heart valve simulations. This methodology is based on a unified continuum fluid-structure interaction model and utilizes standard finite element methods to solve partial differential equations. Contact is modeled using local phase changes in the unified continuum, and computational results demonstrate the potential of this approach.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2021)
Article
Engineering, Multidisciplinary
Nicolas Galano, Patricio A. Moreno-Casas, Jose A. Abell
Summary: This study extends the capabilities of the Particle Finite Element Method (PFEM) to model sediment transport and scouring effects by implementing scouring rules on an evolving scourable-interface. The proposed method improves upon previous proposals by jointly capturing both the temporal and spatial scales of scouring evolution, while conforming with commonplace engineering procedures for scouring prediction. The extension preserves desirable PFEM properties and adds a negligible computational overhead.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Engineering, Biomedical
Luca Dede, Filippo Menghini, Alfio Quarteroni
Summary: An idealized computational model of the left human heart was constructed to study blood flow dynamics, aiming to reproduce normal function. The Navier-Stokes equations in the ALE formulation were solved, and the presence of mitral and aortic valves was considered through the resistive method. The study assessed blood flow characteristics through analysis of velocity fields, blood pressure, and other clinically meaningful fluid dynamics indicators.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING
(2021)
Article
Cardiac & Cardiovascular Systems
Giordano Tasca, Michal Jaworek, Federico Lucherini, Francesco Trinca, Paola Redaelli, Carlo Antona, Riccardo Vismara
Summary: The study compared the effects of the Florida-sleeve technique and the Yacoub technique on aortic leaflet kinematics, showing significant differences in the slow closing phase. The Florida-sleeve technique exhibited notable changes in slow closing time and velocity, while the Yacoub technique showed greater leaflet displacement before rapid closing.
EUROPEAN JOURNAL OF CARDIO-THORACIC SURGERY
(2021)
Article
Cardiac & Cardiovascular Systems
Maria G. C. Nestola, Patrick Zulian, Lisa Gaedke-Merzhauser, Rolf Krause
Summary: This study presents a fully coupled approach for solving contact problems between multiple elastic structures in a fluid flow. The computational model allows for numerical simulation of blood tissue interaction of bioprosthetic heart valves (BHVs) and contact among the leaflets. The study suggests that stresses concentrate in regions where leaflets are attached to the stent and in the portion of the aortic root where the BHV is placed, which may inspire new BHV designs for better stress distribution.
Article
Oncology
Rosalba Portuesi, Alessandro Loppini, Rosanna Mancari, Simonetta Filippi, Nicoletta Colombo
Summary: This study validates the value of inhibin B in detecting recurrences in adult-type granulosa cell tumors of the ovary and explores its role in guiding follow-up examinations and treatment strategies. Results showed that inhibin B is a sensitive and specific marker that may be used during follow-up for detection of recurrences, guiding clinicians in decision-making regarding imaging and avoiding unnecessary tests in the absence of clinical suspicion.
INTERNATIONAL JOURNAL OF GYNECOLOGICAL CANCER
(2021)
Article
Astronomy & Astrophysics
R. Ruffini, R. Moradi, J. A. Rueda, L. Li, N. Sahakyan, Y-C Chen, Y. Wang, Y. Aimuratov, L. Becerra, C. L. Bianco, C. Cherubini, S. Filippi, M. Karlica, G. J. Mathews, M. Muccino, G. B. Pisani, S. S. Xue
Summary: The study suggests that long gamma-ray bursts (GRBs) have binary progenitors, with new examples showing a binary-driven hypernova consisting of a carbon-oxygen core and a neutron star companion. Spectral analysis of prototype GRBs provides insights into the characteristics and evolution of supernovae, GeV emissions, black hole masses, and their rotational energy extraction. The findings indicate the presence of GeV radiation emitted within a cone from the orbital plane and validate the BH mass-energy formula through time evolution analysis.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Multidisciplinary Sciences
N. Parolini, L. Dede', P. F. Antonietti, G. Ardenghi, A. Manzoni, E. Miglio, A. Pugliese, M. Verani, A. Quarteroni
Summary: The paper introduces a novel mathematical epidemiological model named SUIHTER, which reproduces the history of the Italian epidemic and validates its predictive capabilities through parameter calibration, demonstrating its suitability for scenario analysis at a national level.
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2021)
Article
Geochemistry & Geophysics
F. Di Michele, J. May, D. Pera, V Kastelic, M. Carafa, C. Smerzini, I Mazzieri, B. Rubino, P. F. Antonietti, A. Quarteroni, R. Aloisio, P. Marcati
Summary: This paper simulates the earthquake in L'Aquila on April 6, 2009 using an open-source code called SPEED. The results show good agreement with recorded data and demonstrate the potential implications for seismic risk assessment.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2022)
Article
Cardiac & Cardiovascular Systems
Roberto Lorusso, Samuel Heuts, Federica Jiritano, Roberto Scrofani, Carlo Antona, Guglielmo Actis Dato, Paolo Centofanti, Sandro Ferrarese, Matteo Matteuci, Antonio Miceli, Mattia Glauber, Enrico Vizzardi, Sandro Sponga, Igor Vendramin, Andrea Garatti, Carlo de Vincentis, Michele De Bonis, Silvia Ajello, Giovanni Troise, Margherita Dalla Tomba, Filiberto Serraino
Summary: This study aimed to evaluate the predictors of early mortality and complication rates in cardiac surgery patients supported by an intra-aortic balloon pump (IABP). The results showed that the use of perioperative IABP support was safe and associated with relatively low complication rates.
INTERACTIVE CARDIOVASCULAR AND THORACIC SURGERY
(2022)
Article
Computer Science, Interdisciplinary Applications
Christian Vergara, Simone Stella, Massimiliano Maines, Pasquale Claudio Africa, Domenico Catanzariti, Cristina Dematte, Maurizio Centonze, Fabio Nobile, Alfio Quarteroni, Maurizio Del Greco
Summary: This study assessed a computational tool for estimating electrical activation in the left ventricle of patients with left bundle branch block and possible myocardialfibrosis, with a focus on the latest electrically activated segment (LEAS). The results showed that the tool was able to accurately reproduce electrical activation maps and had excellent agreement in LEAS location.
MEDICAL & BIOLOGICAL ENGINEERING & COMPUTING
(2022)
Article
Biochemistry & Molecular Biology
Margherita A. G. Matarrese, Alessandro Loppini, Martina Nicoletti, Simonetta Filippi, Letizia Chiodo
Summary: The study of RNA structure is crucial in understanding RNA molecular functioning. With the flexibility of RNA, the large number of expressed RNAs, and the diverse functions they have, it is difficult to obtain structural information on the same scale as is available for proteins. In silico prediction of RNA 3D structures is particularly important to understand the relationship between structure and function, as the 3D structure plays a significant role in molecular interactions with DNA or protein complexes. The accuracy of RNA 3D structure prediction relies on a properly predicted or measured secondary structure. This paper comparatively evaluates computational tools for modeling RNA secondary structure, focusing on freely available web-server versions for more accessible use. The evaluation focuses on the performance for long sequences and aims to select the best methods for investigating long non-coding RNAs (lncRNAs), which are of special relevance due to their involvement in regulatory mechanisms.
JOURNAL OF BIOMOLECULAR STRUCTURE & DYNAMICS
(2023)
Article
Engineering, Biomedical
Michele Bucelli, Alberto Zingaro, Pasquale Claudio Africa, Ivan Fumagalli, Luca Dede', Alfio Quarteroni
Summary: We have developed a mathematical and numerical model that simulates the various processes involved in heart function, including electrophysiology, mechanics, and hemodynamics. The model also considers the interactions between the different processes, such as electro-mechanical and mechano-electrical feedback. By using a coupled fluid-structure interaction approach, we are able to represent the three-dimensional nature of the heart muscle and hemodynamics. The model has been validated using a realistic human left heart model and shows qualitative and quantitative agreement with physiological ranges and medical images.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING
(2023)
Article
Astronomy & Astrophysics
Y. Aimuratov, L. M. Becerra, C. L. Bianco, C. Cherubini, M. Della Valle, S. Filippi, Liang Li, R. Moradi, F. Rastegarnia, J. A. Rueda, R. Ruffini, N. Sahakyan, Y. Wang, S. R. Zhang
Summary: This article focuses on the observations of supernovae occurring after long gamma-ray bursts. The binary-driven hypernova model is used to explain the origin and evolution of these supernovae. Through multiwavelength observations and theoretical analysis, several new events related to supernovae and gamma-ray bursts have been discovered.
ASTROPHYSICAL JOURNAL
(2023)
Proceedings Paper
Computer Science, Theory & Methods
Nicole Luchetti, Letizia Chiodo, Alessandro Loppini, Simonetta Filippi
Summary: Electrophysiological modeling is a fundamental tool to understand the behavior of excitable cells, but the determination of model parameters is crucial. This study demonstrates how multiscale simulation tools and molecular modeling can provide reliable estimation of ion channel conductance in cell modeling.
PROCEEDINGS OF 2022 IEEE INTERNATIONAL WORKSHOP ON METROLOGY FOR INDUSTRY 4.0 & IOT (IEEE METROIND4.0&IOT)
(2022)
Article
Astronomy & Astrophysics
R. Moradi, J. A. Rueda, R. Ruffini, Liang Li, C. L. Bianco, S. Campion, C. Cherubini, S. Filippi, Y. Wang, S. S. Xue
Summary: The study investigates the physical origin of the ultrarelativistic prompt emission (UPE) phase of GRB 1901140, revealing the presence of a Kerr black hole and a uniform test magnetic field in the inner engine, which generates PEMB pulses through a quantum process. The time-varying mass and spin of the Kerr BH in the inner engine lead to the production of a series of PEMB pulses.
Review
Engineering, Biomedical
M. Stefano, F. Cordella, A. Loppini, S. Filippi, L. Zollo
Summary: Electrical nerve fiber stimulation is widely used in prosthetics and rehabilitation, and computational modeling and numerical simulations play a crucial role in supporting experimental tests. Recent years have seen a growing interest in computational modeling of neural cells and numerical simulations on nerve fibers stimulation, especially in predicting the effects of electrical current stimuli and designing optimal stimulus waveforms.
IEEE TRANSACTIONS ON NEURAL SYSTEMS AND REHABILITATION ENGINEERING
(2021)