Article
Engineering, Multidisciplinary
Pier Nicola Sergi
Summary: This paper proposes a physical-based framework to describe the mechanical constraints of mimicking peripheral nerves extension, and further investigates the role of the tangent modulus and its rate of change with strain in defining the structural biomimicry with peripheral nerves.
Article
Engineering, Biomedical
Outman Akouissi, Stephanie P. Lacour, Silvestro Micera, Antonio DeSimone
Summary: In this study, the mechanical stresses induced on the peripheral nerve by the implant's micromotion were modeled using finite element analysis. The results indicate that the material, geometry, and surface coating of the implant are crucial for its stability and durability. Specifically, implants with smooth edges, materials that are no more than three orders of magnitude stiffer than the nerve, and innovative geometries that redistribute micromotion-associated loads can improve the long-term performance of peripheral nerve implants.
JOURNAL OF NEURAL ENGINEERING
(2022)
Article
Engineering, Biomedical
Petr Marcian, Libor Borak, Tomas Zikmund, Ladislava Horackova, Jozef Kaiser, Marek Joukal, Jan Wolff
Summary: A patient-specific approach in computational simulations of biomechanical systems has gained popularity, but the quality of models created from imaging data may be compromised by low-resolution images. This study analyzed the effects of image resolution on modeling and mechanical strains in bone with implants, finding that low-resolution images can lead to biased results and incorrect mechanical strains.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2021)
Article
Computer Science, Interdisciplinary Applications
Yuki Yamakawa
Summary: The objective of this article is to extend existing hyperelastic constitutive models for geomaterials to include finite strains and examine the model responses. The study reveals significant differences in model responses depending on the types of models, with some models showing unreasonable stress decrease during triaxial compression.
COMPUTERS AND GEOTECHNICS
(2022)
Article
Mechanics
Omid Azarniya, Gholam Husain Rahimi
Summary: In this paper, the hyperelastic behavior of a sandwich beam and isotropic beam is analyzed numerically and experimentally. The natural rubber's mechanical properties are obtained through an axial tensile test based on ASTM D412 standard. The displacement and strain distribution are extracted using the Digital image correlation method in the experimental bending test.
MECHANICS BASED DESIGN OF STRUCTURES AND MACHINES
(2022)
Article
Thermodynamics
Paulo A. G. Piloto, Stephan Gomes, Leonardo Torres, Carlos Couto, Paulo Vila Real
Summary: LSF walls are popular in modern buildings for their high strength-to-weight ratio and ease of installation. However, the empty cavities within these walls can pose a fire risk. Various modelling techniques, including two-dimensional thermal models, can be used to ensure fire resistance and performance. Three computational solution methods were compared for their fire performance, with method 3 providing the best approximation by capturing the main fire events. Based on a parametric study, a new proposal is presented for predicting fire resistance by insulation.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Chemistry, Physical
Radu Stefan Stirbu, Leontin Padurariu, Fereshteh Falah Chamasemani, Roland Brunner, Liliana Mitoseriu
Summary: This paper investigates the microstructure features of soft additives used for producing porous ceramics and the formation mechanism of their anisotropic properties. It is found that equiaxed soft polymeric additives can result in anisotropic porosity in ceramics due to the deformation during the pressing step. Analytical and numerical calculations show that uniaxial pressing of solid particles with contrasting mechanical properties generates modifications in the shape of the soft phase, leading to anisotropic shape distribution of the soft inclusions in the green ceramic body and elongated porosity in the final ceramic product.
Article
Mathematics, Applied
Joao A. Marques da Silva, Miguel Vieira de Carvalho, Rui P. Cardoso Coelho, Igor A. Rodrigues Lopes, Francisco M. Andrade Pires
Summary: This contribution analyzes the convergence behavior of representative volume elements (RVEs) with an increasing number of crystalline grains. The influence of crystallographic slip and mechanically induced martensitic formation is studied. Instead of analyzing a single micromechanical model, the representativeness of the RVEs is assessed through distinct macroscopic simulations. A computationally efficient Taylor's condition (FE-T) is assumed to make the convergence analysis feasible. The results showed that the macroscopic response converges regardless of whether the martensitic transformation is considered or not.
FINITE ELEMENTS IN ANALYSIS AND DESIGN
(2023)
Article
Engineering, Biomedical
Su Guvenir Torun, Hakki M. Torun, Hendrik H. G. Hansen, Chris L. de Korte, Antonius F. W. van der Steen, Frank J. H. Gijsen, Ali C. Akyildiz
Summary: This study successfully predicted the component-wise material properties of atherosclerotic human carotid arteries ex-vivo using an inverse finite element modeling framework, demonstrating potential for pre-clinical applications.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2022)
Article
Clinical Neurology
Stewart Yeoh, Wesley S. Warner, Ilyas Eli, Mark A. Mahan
Summary: The study compared different types of nerve injuries in mice and found that closed traction injuries resulted in more severe and long-term neurological deficits compared to other types of injuries. This suggests that stretch injuries present unique pathology and functional deficits, providing an opportunity to study the pathophysiology of clinical injury mechanisms. Further validation in large animal models will be needed for comparison with human injuries.
JOURNAL OF NEUROSURGERY
(2021)
Article
Engineering, Biomedical
Anne-Cecile Lesage, Alexis Simmons, Anando Sen, Simran Singh, Melissa Chen, Guillaume Cazoulat, Jeffrey S. Weinberg, Kristy K. Brock
Summary: This study evaluated the accuracy and efficiency of various FEM models in predicting inward brain-shift during neurosurgery. Including non-rigid modeling of the meninges was found to be statistically significant for patients with low-grade gliomas.
PHYSICS IN MEDICINE AND BIOLOGY
(2021)
Article
Multidisciplinary Sciences
Yonggou Lou, Lei Chen, Hongbing Wu, Sandy To
Summary: The Ti-6Al-4V titanium alloy is a lightweight material widely used in the aerospace industry due to its high specific strength, corrosion resistance, and heat resistance. However, it presents poor machinability and rapid tool wear during processing. By analyzing the influence of cutting speed on ultra-precision cutting of titanium alloy, it was found that better surface quality could be achieved at lower cutting speeds.
Article
Engineering, Mechanical
Seongyong Yoon, Frederic Barlat
Summary: A non-iterative stress update method is proposed to accelerate finite element simulations in plasticity. This method directly integrates the stress tensor based on elastoplastic constitutive law without needing a recursive root-finding process. The method ensures the positivity of the effective plastic strain increment and resolves the uncertainty of yield condition fulfillment through a stress projection technique. It significantly reduces computation time by approximately 50% while maintaining high accuracy in a variety of finite element simulation examples.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Computer Science, Artificial Intelligence
Jinze Du, Andres Morales, Pragya Kosta, Jean-Marie C. Bouteiller, Gema Martinez-Navarrete, David J. J. Warren, Eduardo Fernandez, Gianluca Lazzi
Summary: Electrical stimulation of the peripheral nervous system is a promising therapeutic option, but its effects on tissue and safety are poorly understood. This study developed computational models of nerves and stimulation cuffs to enhance therapeutic efficacy and avoid tissue damage. The findings suggest the importance of developing safety criteria specific to peripheral nerves using computational bioelectromagnetics and machine learning techniques.
INTERNATIONAL JOURNAL OF NEURAL SYSTEMS
(2023)
Article
Computer Science, Interdisciplinary Applications
Elena Zabolotnii, Norbert R. Morgenstern, G. Ward Wilson
Summary: This paper presents a framework for evaluating mesh sensitivity in numerical models, demonstrated through a case study of failure at the Mount Polley TSF in Canada. The study shows that the failure was caused by strain localization in a shear band, and provides predictions for stability levels under different scenarios. The relationship between a model's discretization, the shape of the strain-weakening curve, and convergence is also discussed.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Cell Biology
Pier Nicola Sergi, Attilio Marino, Gianni Ciofani
INTEGRATIVE BIOLOGY
(2015)
Article
Multidisciplinary Sciences
Iolanda Morana Roccasalvo, Silvestro Micera, Pier Nicola Sergi
SCIENTIFIC REPORTS
(2015)
Article
Materials Science, Biomaterials
Pier Nicola Sergi, Winnie Jensen, Ken Yoshida
MATERIALS SCIENCE & ENGINEERING C-MATERIALS FOR BIOLOGICAL APPLICATIONS
(2016)
Review
Materials Science, Biomaterials
Pier Nicola Sergi, Elisabetta Ada Cavalcanti-Adam
BIOMATERIALS SCIENCE
(2017)
Article
Computer Science, Interdisciplinary Applications
Gianni Ciofani, Pier Nicola Sergi, Jacopo Carpaneto, Silvestro Micera
MEDICAL & BIOLOGICAL ENGINEERING & COMPUTING
(2011)
Article
Engineering, Biomedical
Annarita Cutrone, Pier Nicola Sergi, Silvia Bossi, Silvestro Micera
MEDICAL ENGINEERING & PHYSICS
(2011)
Article
Engineering, Biomedical
Pier Nicola Sergi, Winnie Jensen, Silvestro Micera, Ken Yoshida
MEDICAL ENGINEERING & PHYSICS
(2012)
Article
Multidisciplinary Sciences
Pier Nicola Sergi, Iolanda Morana Roccasalvo, Ilaria Tonazzini, Marco Cecchini, Silvestro Micera
Article
Chemistry, Multidisciplinary
Elisabetta Giannessi, Maria Rita Stornelli, Alessandra Coli, Pier Nicola Sergi
APPLIED SCIENCES-BASEL
(2019)
Article
Chemistry, Multidisciplinary
Pier Nicola Sergi
APPLIED SCIENCES-BASEL
(2020)
Article
Chemistry, Multidisciplinary
Pier Nicola Sergi, Natalia De la Oliva, Jaume del Valle, Xavier Navarro, Silvestro Micera
Summary: The foreign body reaction is a complex biological process that involves the insulation of implanted artificial materials through scar tissue. In chronic implantations of neural electrodes, predicting the evolution of scar tissue is crucial for assessing the implant reliability over time. A novel framework has been proposed in this work to model the evolution of scar tissue thickness, providing accurate reproduction of experimental data and effective prediction of inter-interval detections. This approach improves the overall performance of previous methods based on low-degree fitting polynomials.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Multidisciplinary
Pier Nicola Sergi, Winnie Jensen, Ken Yoshida
Summary: This study investigated the changes in the tip shape of microneedles after insertion into peripheral nerves. The interaction between peripheral nerves and tungsten microneedles was quantified using the Oliver-Pharr formula, and it was found that the interaction force was directly proportional to the power of the normalized indentation depth. Experimental correlations between insertion force and the opening tip angle were described, and the minimum diameter for effective puncture of peripheral nervous tissue was assessed. A computational framework was also presented to describe the local changes affecting the microneedles' tip shape.
APPLIED SCIENCES-BASEL
(2022)
Proceedings Paper
Engineering, Biomedical
I. Morana Roccasalvo, P. N. Sergi, I. Tonazzini, M. Cecchini, S. Micera
2015 37TH ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY (EMBC)
(2015)
Proceedings Paper
Engineering, Biomedical
Silvia Bossi, Pier Nicola Sergi, Silvestro Micera
2009 4TH INTERNATIONAL IEEE/EMBS CONFERENCE ON NEURAL ENGINEERING
(2009)