Article
Electrochemistry
Igor Traskunov, Arnulf Latz
Summary: A body of research investigates how the microstructure of lithium-ion battery electrodes affects their performance. Fluctuations in overpotential and lithium ion concentration, not observed in simulation results based on the DFN model, were explained using analytical and numerical analysis. The study proves that these fluctuations persist and are relevant to real lithium-ion cells, providing insights for more accurate mathematical models.
ELECTROCHIMICA ACTA
(2022)
Review
Instruments & Instrumentation
Greeshma Jacob, Iven Jose, S. Sujatha
Summary: Early detection is crucial for controlling breast cancer, and thermography is a non-invasive method that utilizes temperature differences to identify tumors. This paper focuses on the various aspects of thermography as a diagnostic tool for detecting breast cancer, and it reveals that active thermography is more effective than passive thermography.
INFRARED PHYSICS & TECHNOLOGY
(2023)
Article
Biology
Roger Resmini, Lincoln Faria da Silva, Petrucio R. T. Medeiros, Adriel S. Araujo, Debora C. Muchaluat-Saade, Aura Conci
Summary: Breast cancer is the second most common cancer worldwide, and early diagnosis and treatment are crucial for patient healing. This paper proposes a hybrid computational method using dynamic and static infrared thermography for breast cancer screening and diagnosis, achieving high accuracy through machine learning techniques. The results demonstrate the potential of the proposed approaches in breast cancer screening and diagnosis.
COMPUTERS IN BIOLOGY AND MEDICINE
(2021)
Article
Mechanics
Qiang Fu, Yiqian He, Jin Guo, Xinglin Guo, Haitian Yang
Summary: A novel semi-analytical method is proposed to predict the effective properties of viscoelastic composites. By utilizing a temporal series expansion and a recursive homogenization process, time varying effective strain/stress can be obtained and computed accurately using a recursive adaptive algorithm.
Article
Mechanics
R. Rodriguez-Ramos, V. Yanes, Y. Espinosa-Almeyda, J. A. Otero, F. J. Sabina, C. F. Sanchez-Valdes, F. Lebon
Summary: This work derives the effective properties of heterogeneous micropolar media with periodic structure using the two-scale asymptotic homogenization method. The study focuses on centro-symmetric Cosserat composites with isotropic and cubic constituents. The analytical expressions for the local problems and effective coefficients are provided, and closed-form formulae of the effective properties are obtained. The study also compares the classical and Cosserat effective elastic properties for laminated composites with isotropic constituents.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Mechanics
Laura Miller, Raimondo Penta
Summary: In this work, we investigate the influence of microstructure on elastic parameters in poroelastic materials. Comparing with a standard poroelastic approach, we consider the effects of multiple elastic and fluid phases based on the LMRP model. By using the asymptotic homogenization approach, we summarize both the LMRP model and the standard approach, and provide the required 3D and 2D boundary loads for numerical simulations. Our results show that the LMRP model is more appropriate for poroelastic composite materials with porosity exceeding 5%, especially in terms of Young's moduli E1 and E3 and the shear C44. When the porosity exceeds 20%, it should also be used for investigating the shear C66. For materials with porosity less than 5%, both the standard poroelastic approach and the LMRP model yield the same results.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Medicine, Research & Experimental
Guohong Liu, Liping Wang, Lili Ji, Dan He, Lihua Zeng, Guangzheng Zhuo, Qian Zhang, Dujuan Wang, Yunbao Pan
Summary: By utilizing GeoMx Digital Spatial Profiling (DSP) technology, we analyzed transcripts from 107 regions of interest in 65 untreated breast cancer tissue samples to gain deeper insights into the microenvironment of breast cancer. Our study revealed spatial heterogeneity in the expression of marker genes in tumor cell enriched, immune cell enriched, and normal epithelial areas. Through our investigations, we discovered specific diagnostic and prognostic markers in breast cancer.
JOURNAL OF TRANSLATIONAL MEDICINE
(2023)
Article
Engineering, Aerospace
Yufeng Xing, Lingyu Meng, Zhiwei Huang, Yahe Gao
Summary: This paper presents a novel superposition method for effectively predicting the microscopic stresses of heterogeneous periodic beam-like structures. The method combines the solutions of the microscopic unit cell problem with the solutions of the macroscopic equivalent beam problem to accurately and effectively predict the microscopic stresses of whole composite beams. The method is applicable to composite beams with arbitrary periodic microstructures and load conditions.
Review
Oncology
Xiaolu Sun, Kuai Liu, Shuli Lu, Weina He, Zixiu Du
Summary: Breast cancer is a molecularly diverse disease with heterogeneity. Targeted therapy and immunotherapy offer solutions to improve prognosis and address drug resistance. Molecular classifications are important for clinical diagnosis and treatment strategies differ according to the molecular subtype. Targeted therapy and immunotherapy provide hope for the treatment of breast cancer.
Article
Mechanics
Zhelong He, Marek-Jerzy Pindera
Summary: In this study, a finite volume approach was used to solve unit cell problems for unidirectional fiber-reinforced periodic structures under anti-plane shear loading, extending previous research. By considering strain gradients and the relationship between microstructural scale and structural dimensions, the study achieved accurate recovery of local fields through solving unit cell problems.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2021)
Article
Computer Science, Software Engineering
Peiqing Liu, An Liu, Hao Peng, Lihao Tian, Jikai Liu, Lin Lu
Summary: The research focuses on designing the topology of microstructures and adjusting their material properties, especially on the integral image covering multiple mechanical properties of microstructures. A mechanical property profile (MPP) is proposed to describe mechanical properties, visualized using a radar chart, and joints reinforcement is applied to enhance the strength of microstructures.
COMPUTERS & GRAPHICS-UK
(2021)
Article
Immunology
Angela Quintana, Enrique Javier Arenas, Cristina Bernado, Jose Fernandez Navarro, Jonatan Gonzalez, Anna Esteve-Codina, Teresa Moline, Merce Marti, Giuseppe Curigliano, Peter Schmid, Vicente Peg, Joaquin Arribas, Javier Cortes
Summary: The heterogeneity of immune infiltration in breast cancer is an important research area. This study found that the heterogeneity of TILs is related to the presence of immune infiltration, rather than patient characteristics.
FRONTIERS IN IMMUNOLOGY
(2023)
Article
Geosciences, Multidisciplinary
Mathias Lebihain, Thibault Roch, Marie Violay, Jean-Francois Molinari
Summary: The study presents a comprehensive analytical framework to predict the influence of linearly slip-dependent friction laws on earthquake nucleation length. Results show that the interplay between frictional properties and asperity size leads to three instability regimes, and that the influence of heterogeneities at a scale far lower than the nucleation length can be averaged.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Yasutomo Uetsuji, Fumiya Sano, Shun Takeuchi
Summary: This paper proposes a multiscale optimum design for the transverse magnetoelectric (ME) constant, which cannot exhibit sufficient characteristics in conventional multi-layered structures or vertical aligned composite structures. The asymptotic homogenization theory is adopted for scale coupling and a computational optimization scheme is constructed using the three-dimensional finite element method. The computation successfully discovers a new optimized heterostructure with a transverse ME constant equivalent to 10 to 20 times that of conventional composites. The mechanism of periodic polarization inversion effect in the optimized heterostructures is elucidated, which efficiently enhances the local torsional deformation around the ferroelectric phase without waste and promotes the development of global ME effect without cancellation. The obtained optimal design is expected to be applied to 3D printing of ME composites and has a significant impact on accelerating the development of new materials for the next generation.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Engineering, Multidisciplinary
Wei-Zhi Luo, Qi-Chang He, Hung Le Quang
Summary: This paper examines the application of the two-scale asymptotic method and Willis' method in the elastodynamic homogenization of periodic composites. The effective elastodynamic constitutive law given by Willis' method, which is non-local both in time and space, is reformulated to obtain a compact expression for the effective impedance tensor. The results obtained by the two-scale asymptotic method are shown to be an approximation to the general results delivered by Willis' method. The solutions for the hierarchical motion equations obtained from asymptotic analysis have a compact recursive representation. A generic compact expression is derived for the effective impedance tensor associated with the nth-order approximation of asymptotic analysis, which turns out to be formally identical to the one obtained via Willis' method. The elastodynamic homogenization of a layered composite undergoing anti-plane shear is investigated as an illustrative example.
APPLIED MATHEMATICAL MODELLING
(2023)
Article
Mechanics
J. A. Otero, R. Rodriguez-Ramos, Y. Espinosa-Almeyda, F. J. Sabina, V. Levin
Summary: In this study, effective coefficients for a two-phase visco-piezoelastic composite reinforced by cylindrical fibers embedded in a matrix are derived using effective field and asymptotic homogenization approaches. The composite consists of an isotropic viscoelastic matrix reinforced by piezoelastic fibers, with the fibers oriented along the x3-axis and arranged in a hexagonal cell. Closed formulas are obtained based on Rabotnov's fractional exponential kernel, and the model is validated through limit cases. Numerical implementation and comparison between both approaches are conducted for the effective coefficients, along with computation of electromechanical coupling coefficients for ultrasonic pulse-echo transducers in medical applications.
Article
Biophysics
Laura Miller, Raimondo Penta
Summary: In this study, we investigate the impact of microstructural changes induced by myocardial infarction on the elastic parameters of the heart. We use a poroelastic composite model to describe the myocardium microstructure and consider changes such as loss of myocyte volume and increased matrix fibrosis in the areas surrounding the infarct. Our simulations show that the infarcted heart is stiffer than the healthy heart, but with reperfusion, it begins to soften. We also observe that an increase in myocyte volume leads to a softer myocardium. These findings provide insights into predicting the stiffness and volume changes in the heart post-infarction.
BIOMECHANICS AND MODELING IN MECHANOBIOLOGY
(2023)
Article
Mechanics
Laura Miller, Raimondo Penta
Summary: In this work, we investigate the influence of microstructure on elastic parameters in poroelastic materials. Comparing with a standard poroelastic approach, we consider the effects of multiple elastic and fluid phases based on the LMRP model. By using the asymptotic homogenization approach, we summarize both the LMRP model and the standard approach, and provide the required 3D and 2D boundary loads for numerical simulations. Our results show that the LMRP model is more appropriate for poroelastic composite materials with porosity exceeding 5%, especially in terms of Young's moduli E1 and E3 and the shear C44. When the porosity exceeds 20%, it should also be used for investigating the shear C66. For materials with porosity less than 5%, both the standard poroelastic approach and the LMRP model yield the same results.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Biology
Tahani Al Sariri, Radostin D. Simitev, Raimondo Penta
Summary: We propose a new mathematical model for blood flow, nanoparticles delivery, and heat transport in vascularised tumour tissue. The model, derived through asymptotic homogenisation technique, provides a connection between the system's macroscale behaviour and its underlying micro-structure. By using finite element method to perform simulations, we investigate the influence of vessel geometry on tumour temperature and determine the optimal conditions for hyperthermia treatment.
JOURNAL OF THEORETICAL BIOLOGY
(2023)
Article
Chemistry, Physical
Alejandro Roque-Piedra, Reinaldo Rodriguez-Ramos, Raimondo Penta, Ariel Ramirez-Torres
Summary: We propose a general approach to compute the effective properties of nonlinear viscoelastic composites. By using the asymptotic homogenisation technique, the equilibrium equation is decoupled into local problems. We apply this approach to the case of Saint-Venant-type strain energy density with a memory contribution in the second Piola-Kirchhoff stress tensor. The effective coefficients are computed by specifying different constitutive laws for the memory terms, and the results are compared with existing data in the scientific literature.
Article
Multidisciplinary Sciences
M. H. B. M. Shariff, J. Merodio, R. Bustamante
Summary: In the past, fibre stiffness of finite-radius fibres was modelled using nonlinear models based on strain-gradient theory or Kirchhoff rod theory. However, these models have limitations in characterizing the mechanical behaviour of non-polar elastic solids with finite-radius fibres. This paper proposes a simple and realistic constitutive equation for non-polar elastic solids reinforced by embedded fibres, without using the second gradient theory.
SCIENTIFIC REPORTS
(2023)
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
Mechanics
V. Yanes, Y. Espinosa-Almeyda, R. Rodriguez-Ramos, C. F. Sanchez-Valdes, F. J. Sabina, F. J. Montans
Summary: This paper addresses the homogenization theory for three-dimensional linear micropolar composite materials with centro-symmetric constituents and non-uniform imperfect interface conditions. The imperfect contact conditions are modeled using a generalization of the spring model, where tractions and coupled stresses are continuous, but displacements and microrotations are discontinuous across the interface. The two-scale asymptotic homogenization method (AHM) is developed to find the analytical statement of the local problems on the periodic cell and the corresponding effective coefficients.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2023)
Article
Engineering, Multidisciplinary
Ivan I. Argatov, Federico J. Sabina
Summary: AFM-based stiffness tomography presents new challenges in indentation for elastic samples with heterogeneities. A model is proposed for fibrous organelles inside living cells, where a stiff infinite elastic fiber is buried in an elastic half-space. The frictionless unilateral indentation is analyzed using matched asymptotic expansions, assuming a small contact area compared to the depth of the fiber. Fiber deformation is described using Euler's theory of bending and the resulting integro-differential equations are solved using Fourier transform. An explicit relation between indenter displacement and contact force is derived, and the fiber influence factor is introduced to evaluate the incremental indentation stiffness.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2023)
Article
Mathematics, Applied
Ariel Ramirez-Torres, Raimondo Penta, Alfio Grillo
Summary: In this study, a two-scale asymptotic homogenization approach is adopted to investigate the effective properties of fractional viscoelastic composites. The focus is on a purely mechanical setting and the cell and homogenized problems are derived for the balance of linear momentum equation. The original framework is reformulated in the Laplace-Carson domain and effective coefficients are obtained in the time domain. Different combinations of constitutive models including elastic, fractional Kelvin-Voigt, fractional Zener, and fractional Maxwell constituents are considered. The results provide an interpretation of the theoretical findings and elucidate the role of fractional constitutive models on effective properties.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2023)
Article
Engineering, Mechanical
Hadi Asghari, Heiko Topol, Bernd Markert, Jose Merodio
Summary: This paper applies Sobol method and the Fourier Amplitude Sensitivity Test (FAST) method to analyze the influence of input parameters on the output variable in the problem of mixed extension, inflation, and torsion of a circular cylindrical tube with residual stress. The input parameters are distributed according to uniform, gamma, and normal distributions. The most influential factors are determined using Sobol and FAST methods, and the bias and standard deviation of Sobol and FAST indices are calculated to assess the results.
PROBABILISTIC ENGINEERING MECHANICS
(2023)
Article
Chemistry, Physical
Laura Miller, Ariel Ramirez-Torres, Reinaldo Rodriguez-Ramos, Raimondo Penta
Summary: This paper derives the governing equations for the overall behavior of linear viscoelastic composites consisting of two families of elastic inclusions and an incompressible Newtonian fluid at the microscale. Using the asymptotic homogenization method, a new homogenized model is derived by upscaling the fluid-structure interaction problem. The model has coefficients that encode the properties of the microstructure and can be computed by solving a single local differential fluid-structure interaction problem.
Article
Mechanics
Andrey Melnikov, Jose Merodio
Summary: This paper examines the influence of residual stress on the stability of an inflated, axially extended circular cylindrical tube. It is found that the effect of residual stress varies depending on the type of bifurcation, with residual stress increasing stability for asymmetric bifurcations and leading to increased instabilities for axisymmetric bifurcations.
JOURNAL OF APPLIED AND COMPUTATIONAL MECHANICS
(2023)
Proceedings Paper
Computer Science, Interdisciplinary Applications
Raffael Paranhos, Aura Conci
Summary: This work presents a simple and efficient method for computing deforestation area using Landsat 8 satellite images. It focuses on the best band and segmentation based on thresholding. The described approach can be easily applied to publicly available images of this type and can be implemented in any computing language or downloaded from a public repository. The difficulty of finding benchmarks for result comparison makes the presented material valuable.
ICGG 2022 - PROCEEDINGS OF THE 20TH INTERNATIONAL CONFERENCE ON GEOMETRY AND GRAPHICS
(2023)
Article
Biology
Iain Hunter, Raz Leib
Summary: Natural movement is related to health, but it is difficult to measure. Existing methods cannot capture the full range of natural movement. Comparing movement across different species helps identify common biomechanical and computational principles. Developing a system to quantify movement in freely moving animals in natural environments and relating it to life quality is crucial. This study proposes a theoretical framework based on movement ability and validates it in Drosophila.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Andy Gardner
Summary: Fisher's geometric model is a useful tool for predicting key properties of Darwinian adaptation, and here it is applied to predict differences between the evolution of altruistic versus nonsocial phenotypes. The results suggest that the effect size maximizing probability of fixation is smaller in the context of altruism and larger in the context of nonsocial phenotypes, leading to lower overall probability of fixation for altruism and higher overall probability of fixation for nonsocial phenotypes.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Thomas F. Pak, Joe Pitt-Francis, Ruth E. Baker
Summary: Cell competition is a process where cells interact in multicellular organisms to determine a winner or loser status, with loser cells being eliminated through programmed cell death. The winner cells then populate the tissue. The outcome of cell competition is context-dependent, as the same cell type can win or lose depending on the competing cell type. This paper proposes a mathematical framework to study the emergence of winner or loser status, highlighting the role of active cell death and identifying the factors that drive cell competition in a cell-based modeling context.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Haruto Tomizuka, Yuuya Tachiki
Summary: Batesian mimicry is a strategy in which palatable prey species resemble unpalatable prey species to avoid predation. The evolution of this mimicry plays a crucial role in protecting the unpalatable species from extinction.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Jason W. Olejarz, Martin A. Nowak
Summary: Gene drive technology shows potential for population control, but its release may have unpredictable consequences. The study suggests that the failure of suppression is a natural outcome, and there are complex dynamics among wild populations.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Hamid Ravaee, Mohammad Hossein Manshaei, Mehran Safayani, Javad Salimi Sartakhti
Summary: Gene expression analysis is valuable for cancer classification and phenotype identification. IP3G, based on Generative Adversarial Networks, enhances gene expression data and discovers phenotypes in an unsupervised manner. By converting gene expression profiles into images and utilizing IP3G, new phenotype profiles can be generated, improving classification accuracy.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Beatrix Rahnsch, Leila Taghizadeh
Summary: This study forecasts the evolution of the COVID-19 pandemic in Germany using a network-based inference method and compares it with other approaches. The results show that the network-inference based approach outperforms other methods in short-to mid-term predictions, even with limited information about the new disease. Furthermore, predictions based on the estimation of the reproduction number in Germany can yield more reliable results with increasing data availability, but still cannot surpass the network-inference based algorithm.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Rongsheng Huang, Qiaojun Situ, Jinzhi Lei
Summary: Maintaining tissue homeostasis requires appropriate regulation of stem cell differentiation. Random inheritance of epigenetic states plays a pivotal role in stem cell differentiation. This computational model provides valuable insights into the intricate mechanism governing stem cell differentiation and cell reprogramming, offering a promising path for enhancing the field of regenerative medicine.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Patrick Vincent N. Lubenia, Eduardo R. Mendoza, Angelyn R. Lao
Summary: This study compares insulin signaling in healthy and type 2 diabetes states using reaction network analysis. The results show similarities and differences between the two conditions, providing insights into the mechanisms of insulin resistance, including the involvement of other complexes, less restrictive interplay between species, and loss of concentration robustness in GLUT4.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Nuverah Mohsin, Heiko Enderling, Renee Brady-Nicholls, Mohammad U. Zahid
Summary: Mathematical modeling is crucial in understanding radiobiology and designing treatment approaches in radiotherapy for cancer. This study compares three tumor volume dynamics models and analyzes the implications of model selection. A new metric, the point of maximum reduction of tumor volume (MRV), is introduced to quantify the impact of radiotherapy. The results emphasize the importance of caution in selecting models of response to radiotherapy due to the artifacts imposed by each model.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Armindo Salvador
Summary: Michael Savageau's Biochemical Systems Analysis papers have had a significant impact on Systems Biology, generating core concepts and tools. This article provides a brief summary of these papers and discusses the most relevant developments in Biochemical Systems Theory since their publication.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
