Article
Materials Science, Multidisciplinary
Zhouzhou Pan, Laurence Brassart
Summary: Biodegradable synthetic hydrogels have shown promise for tissue engineering and drug/cell delivery applications, but successful implementation requires a precise understanding of degradation response. This work presents a thermodynamically-consistent framework and constitutive models for simulating degradation-induced swelling in hydrogels, validated against experimental data. The models could be beneficial for designing hydrogels with controlled degradation behavior.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2022)
Article
Mechanics
Baiwei Zhang, Jun Luo
Summary: In this paper, a novel phase field (PF) model for fracture is developed within the framework of strain gradient elasticity. The model is numerically implemented and validated through analysis of stress fields near static crack tips, with various strain energy decomposition methods compared and discussed for their impact on fracture behavior. The study demonstrates the efficacy of the proposed PF model in predicting complex fracture behaviors under gradient elasticity.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Optics
Junhe Zhou
Summary: This paper proposes a theoretical framework to investigate the impact of unequal losses on quantum interference in coupled waveguides. The framework is tested with two different systems of varying size.
Article
Materials Science, Multidisciplinary
M. Budnitzki, S. Sandfeld
Summary: In this study, a framework based on first strain gradient elasticity is introduced to regularize the dislocation core, with two different strain energy densities compared. The results show that strain energy quadratic in the gradient of the full deformation tensor can regularize both stresses and driving forces for the order parameter.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2021)
Article
Engineering, Mechanical
Balint Fazekas, Tibor J. Goda
Summary: A hyper-visco-pseudo-elastic constitutive equation is introduced in this paper to model the complex behavior of filled rubbers, considering the effects of temperature and residual strains. Model parameters are determined through uniaxial stress relaxation-recovery tests and cyclic uniaxial tensile and simple shear tests at different strain rates, and theoretical results are compared with experimental data for EPDM rubber filled with carbon black.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Mechanics
Giovanni Romano, Marina Diaco
Summary: Nonlocal elasticity models are addressed through a general formulation involving source and target fields in dual Hilbert spaces. The focus is on small movements and a geometrically linearized approximation is assumed feasible. The analysis discusses the linear, symmetric, and positive definite relationship between dual fields in the local elastic law, governed by a strictly convex, quadratic energy functional.
Article
Cardiac & Cardiovascular Systems
Marisol Romero-Tejeda, Hananeh Fonoudi, Carly J. Weddle, Jean-Marc DeKeyser, Brian Lenny, K. Ashley Fetterman, Tarek Magdy, Yadav Sapkota, Conrad L. Epting, Paul W. Burridge
Summary: Reprogramming of somatic cells to cardiomyocyte-like state has been successful in mice but less successful in humans, limiting its clinical applicability in regenerative medicine. To overcome this issue, novel transcription factor candidates were identified using the Mogrify algorithm. Through a high-throughput screening approach, the combination of MYOCD, SMAD6, and TBX20 was found to be the most successful in direct reprogramming of human cardiac fibroblasts to cardiomyocytes, achieving up to 40% TNNT2+ cells in just 25 days. This progress represents a step forward in clinical application of cardiac reprogramming.
JOURNAL OF MOLECULAR AND CELLULAR CARDIOLOGY
(2023)
Article
Cardiac & Cardiovascular Systems
Sabine Lotteau, Rui Zhang, Adina Hazan, Christina Grabar, Devina Gonzalez, Stephan Aynaszyan, Kenneth D. Philipson, Michela Ottolia, Joshua Goldhaber
Summary: This study developed a tamoxifen-inducible NCX1 knockout mouse model, finding that NCX1 KO mice adapt to acute genetic ablation by reducing Ca2+ influx, increasing alternative Ca2+ efflux pathways, and increasing excitation-contraction coupling gain to maintain contractility at the cost of mild hypertrophy and fibrosis, with decreased survival. However, KO myocytes are protected against spontaneous action potentials and ischemia/reperfusion injury.
JOURNAL OF THE AMERICAN HEART ASSOCIATION
(2021)
Article
Mechanics
Mengsi Huang, Peijun Wei, Lina Zhao, Yueqiu Li
Summary: This study investigates the possible coupled elastic waves in a thermoelastic semiconduction micro-beam, considering the coupling effects of the carrier field, temperature field, and elastic displacement field. By incorporating nonlocal strain gradient elasticity, non-Fourier heat conduction, and fraction derivative into the model, a more flexible and enriched model with multiple physical fields coupled is obtained. The study reveals the existence of five possible coupled elastic waves, with comparisons made on the dispersion and attenuation characteristics and their coupling modes. Analysis on the influences of nonlocal parameter, strain gradient parameter, thermal relaxation time, and fraction order parameters are discussed based on numerical results.
COMPOSITE STRUCTURES
(2021)
Article
Cardiac & Cardiovascular Systems
Michael Frisk, Christopher Le, Xin Shen, Asmund T. Roe, Yufeng Hou, Ornella Manfra, Gustavo J. J. Silva, Isabelle van Hout, Einar S. Norden, J. Maguns Aronsen, Martin Laasmaa, Emil K. S. Espe, Fouad A. Zouein, Regis R. Lambert, Christen P. Dahl, Ivar Sjaastad, Ida G. Lunde, Sean Coffey, Alessandro Cataliotti, Lars Gullestad, Theis Tonnessen, Peter P. Jones, Raffaele Altara, William E. Louch
Summary: HFpEF patients showed increased t-tubule density compared to controls, while HFrEF patients had reduced t-tubule density. This suggests distinct cardiomyocyte phenotypes underlie these heart failure entities.
JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY
(2021)
Article
Engineering, Mechanical
Luis C. M. da Silva, Nicola Grillanda, Siro Casolo
Summary: This article presents a two-dimensional molecular model for elastic nonlinear modeling and design of meta-materials. Based on a heuristic molecule (HM) approach, the fundamental unit-cell consists of atoms interacting through centred and non-centred spring-based bonds. The model allows for large displacements and finite strains, and the specific topology of the HM can be modified to change the shape of the atoms and bonds. The HM provides a quasi-isotropic elastic response for both deviatoric and volumetric large deformation modes.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Computer Science, Interdisciplinary Applications
M. A. Moratilla-Vega, M. Angelino, H. Xia, G. J. Page
Summary: In this study, an open-source fast coupling interface for high-order acoustic propagation is introduced, which is implemented between OpenFOAM and Nektar++. The validation results demonstrate the high efficiency of the coupling interface compared to traditional file-based coupled methods, with good agreement with the analytical solution in a 2D cylinder case. Additionally, a more complex rod-airfoil wake interaction case is studied to verify the applicability of the methodology. The adaptation of the interface to other similar solvers/packages is expected to be straightforward.
COMPUTER PHYSICS COMMUNICATIONS
(2022)
Article
Engineering, Multidisciplinary
Sanjeev Kumar
Summary: The local scaling symmetry of the Lagrange density is used to study the electro-mechanical coupling effects in elastic dielectrics. This approach not only explains the induced polarization and electric potential, but also considers the geometric foundations. By introducing minimal replacement and the concept of gauge compensating one form field, the gauge invariance of the Lagrange density is restored. Different components of the gauge invariant energy density are constructed using scale invariant gauge curvature. Numerical simulations and validation demonstrate the effectiveness of the theory. Explorations of this kind of coupling could have significant implications in various industrial and laboratory applications.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Energy & Fuels
Manuel Pineda-Arciniega, Marco A. A. Arjona, Concepcion Hernandez, Rafael Escarela-Perez
Summary: This paper presents a methodology to program the weak coupling between magnetic and structural vector fields in an electromagnetic device modeled in 2D. It proposes a numerical solution using the finite element method and provides a flexible and intuitive methodology for implementing the complex mathematics into a computer program. The proposed approach is validated by comparing the results with a commercial software.
Article
Polymer Science
Pawel Szeptynski, Matija Gams, Arkadiusz Kwiecien
Summary: This study discusses the practical aspects of modeling flexible adhesives using the energy conjugate measures of stress and strain from the Darijani-Naghdabadi (D-N) family. The approach proposed in the study provides practical formulas for describing the behavior of materials with nonlinear characteristics in chosen mechanical states. Experimental results from tests on Sika PM polyurethane were compared with theoretical estimates obtained using the D-N energy conjugate stress and strain measures.
Article
Engineering, Multidisciplinary
Ricardo Ruiz-Baier, Matteo Taffetani, Hans D. Westermeyer, Ivan Yotov
Summary: In this study, a new mixed-primal finite element scheme was proposed to solve the multiphysics model involving fluid flow and consolidation equations without the need for Lagrange multipliers. The research focused on numerical simulations related to geophysical flows and eye poromechanics, exploring different interfacial flow regimes that could help understand early morphologic changes associated with glaucoma in canine species.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
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
Materials Science, Multidisciplinary
Anna Pandolfi, Maria Laura De Bellis, Alessio Gizzi, Marcello Vasta
Summary: This article proposes an enriched micromechanical model to study the role of collagen in eye stromal tissue. By using a more realistic chemical bond model and introducing a pseudo-chemical potential, the model provides a better understanding of conditions such as corneal bulging and tissue degradation.
MATHEMATICS AND MECHANICS OF SOLIDS
(2023)
Article
Mathematics, Applied
Gabriel N. Gatica, Bryan Gomez-Vargas, Ricardo Ruiz-Baier
Summary: In this paper, the a posteriori error analysis for mixed-primal and fully-mixed finite element methods approximating the stress-assisted diffusion of solutes in elastic materials is developed. Two efficient and reliable residual-based a posteriori error estimators are derived and their performance is confirmed through numerical tests, illustrating the effectiveness of adaptive mesh refinement.
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
(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
Mathematics, Applied
Aymen Laadhari, Yves Barral, Gabor Szekely
Summary: In this paper, a variational data assimilation approach is proposed to incorporate data measurements into the simulation of molecule mobility in the yeast endoplasmic reticulum. The approach integrates experimental data and an optimal control problem formulation to study the kinetics of fluorescently labeled molecules in budding yeast. The numerical results support the presence of a physical diffusion barrier that compartmentalizes the endoplasmic reticulum membrane.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2023)
Article
Mathematics, Applied
Mohammed D. Kassim, Mubarak Alqahtani, Nasser-Eddine Tatar, Aymen Laadhari
Summary: In this paper, the nonexistence of nontrivial global solutions is investigated for a class of sequential fractional differential inequalities involving Caputo fractional derivatives with different orders. The investigation is conducted in a suitable space using the test function technique and properties of fractional integrals. Numerical examples are presented to support the obtained results.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2023)
Article
Multidisciplinary Sciences
Aymen Laadhari, Ahmad Deeb
Summary: In this article, a finite element method is presented to study the dynamic behavior of deformable vesicles in a non-Newtonian Casson fluid. The fluid membrane, represented by an implicit level-set function, follows the Canham-Helfrich model and maintains surface inextensibility through penalty. A two-step time integration scheme is proposed, incorporating higher-order accuracy and variable time steps generated by an appropriate adaptation criterion. The model is validated through numerical simulations and its influence on membrane regimes in a non-Newtonian fluid is demonstrated.
Article
Multidisciplinary Sciences
Mohd Halim Bin Mohd Shariff, Jose Merodio, Roger Bustamante, Aymen Laadhari
Summary: The study of the mechanical behavior of fibre-reinforced electroactive polymers (EAPs) with bending stiffness is important for mechanical design and problem solving in engineering. However, there is a lack of constitutive models for fibre-reinforced EAPs with fibre bending stiffness in the existing literature. Therefore, it is crucial to develop a relevant constitutive equation to enhance the understanding of their mechanical behavior. In this paper, a constitutive equation is proposed for a nonlinear nonpolar EAP reinforced by embedded fibres, considering the elastic resistance of the fibres to bending without using the second gradient theory that assumes the existence of contact torques. This model is simpler and more realistic, particularly for nonpolar EAPs where contact torques do not exist.
Article
Mathematics
Aymen Laadhari
Summary: We propose a computational framework for modeling an inextensible single vesicle driven by the Helfrich force in an incompressible, non-Newtonian extracellular Carreau fluid. The level set strategy is used to capture the vesicle membrane, and a penalty method is introduced to relax the local inextensibility constraint, leading to computational savings and easier implementation. The membrane force is accurately calculated using a high-order Galerkin finite element approximation, which includes high-order derivatives. The time discretization is based on the double composition of the one-step backward Euler scheme, and the time step size is flexibly controlled using a time integration error estimation. Numerical examples are provided to validate and assess the model's physiological relevance, and optimal convergence rates of the time discretization are obtained.
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)
Article
Engineering, Electrical & Electronic
D. Lo Presti, A. Dimo, L. Zoboli, D. Bianchi, C. Massaroni, V. Altomare, A. Grasso, C. M. Oddo, A. Gizzi, E. Schena
Summary: This study introduces an innovative tactile probe for breast cancer identification, utilizing fiber Bragg grating (FBG) technology combined with 3D printing. The sensing unit design was optimized through analysis, fabrication, and characterization, leading to the development of a prototype integrating multiple sensing units. Promising results were obtained through tests on silicone samples with different hardness and a phantom mimicking early stage breast tumor, providing guidance for further optimization of the probe design.
IEEE SENSORS JOURNAL
(2023)
Article
Mathematics, Applied
Aymen Laadhari, Ahmad Deeb, Badr Kaoui
Summary: We propose a numerical framework for simulating the dynamics of vesicles with inextensible membranes in a non-Newtonian fluid environment. The framework utilizes a penalty method for handling the inextensibility constraint and higher degree finite elements for spatial discretization. The time integration scheme relies on the Crank-Nicolson scheme and an adaptive time-stepping strategy. The proposed method is benchmarked against existing numerical and experimental results and the influence of non-Newtonian rheology on the system dynamics is investigated.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2023)
