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Cohesive and adhesive bindings degrade during operation and maintenance even if contacting materials in a manufactured laminated structure are perfectly matched at the interfaces. Two modelling approaches for describing partially closed delaminations or imperfect contact zones, which often occurs at the interfaces, are examined and considered. To confirm the adequateness of the applicability of the effective spring boundary conditions for guided wave scattering by a finite length delamination, guided wave propagation through a damaged zone with a distribution of micro-cracks is compared with an equivalent cohesive zone model, where the spring stiffnesses for the effective boundary conditions are calculated using the properties of the considered crack distribution. Two kinds of local interfacial decohesion zones with an imperfect contact at the interfaces are considered: uniform partially closed delaminations and bridged cracks. The possibility of the employment of the effective spring boundary conditions to substitute a distribution of micro-cracks is analysed and discussed. Two algorithms of generation of a distribution of open micro-cracks providing characteristics equivalent to the effective boundary conditions are presented and examined. The influence of the characteristics of a delamination on wave characteristics (eigenfrequencies, eigenforms, transmission coefficient) is investigated for several kinds of partially closed delaminations.
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http://dx.doi.org/10.3390/ma16062415 | DOI Listing |
Philos Trans A Math Phys Eng Sci
September 2025
Department of Mathematics, University of York, York, UK.
Active suspensions, which consist of suspended self-propelling particles such as swimming microorganisms, often exhibit non-trivial transport properties. Continuum models are frequently employed to elucidate phenomena in active suspensions, such as shear trapping of bacteria, bacterial turbulence and bioconvection patterns in suspensions of algae. Yet, these models are often empirically derived and may not always agree with the individual-based description of active particles.
View Article and Find Full Text PDFJ Prosthet Dent
September 2025
Full Professor, School of Mechanical Engineering, Universidad Industrial de Santander, Bucaramanga, Colombia. Electronic address:
Statement Of Problem: Although custom temporomandibular joint (TMJ) prostheses manufactured via computer-aided design and manufacturing (CAD-CAM) and produced through 3-dimensional (3D) printing or computer numerical control (CNC) allow for sagittal curvature adjustments in the glenoid fossa, their design remains unregulated by the Food and Drug Administration. Consequently, the geometry is determined largely by the engineer's discretion, with limited biomechanical evidence to guide these decisions. The lack of validation regarding how sagittal curvature influences joint stress distribution under various anatomical and functional conditions represents a gap in current knowledge that warrants investigation.
View Article and Find Full Text PDFCell
September 2025
Department of Infectious Disease, Imperial College London, London SW7 2AZ, UK; Centre for Bacterial Resistance Biology, Imperial College London, London SW7 2AZ, UK; School of Health Sciences, Universidad CEU Cardenal Herrera, CEU Universities, 46115 Alfara del Patriarca, Spain. Electronic address: j
Some mobile genetic elements spread among unrelated bacterial species through unknown mechanisms. Recently, we discovered that identical capsid-forming phage-inducible chromosomal islands (cf-PICIs), a new family of phage satellites, are present across multiple species and genera, raising questions about their widespread dissemination. Here, we have identified and characterized a new biological entity enabling this transfer.
View Article and Find Full Text PDFComput Biol Med
September 2025
INSIGNEO Institute for in silico medicine, University of Sheffield, UK; School of Mechanical, Aerospace and Civil Engineering, University of Sheffield, UK. Electronic address:
Modelling cardiovascular disease is at the forefront of efforts to use computational tools to assist in the analysis and forecasting of an individual's state of health. To build trust in such tools, it is crucial to understand how different approaches perform when applied to a nominally identical scenario, both singularly and across a population. To examine such differences, we have studied the flow in aneurysms located on the internal carotid artery and middle cerebral artery using the commercial solver Ansys CFX and the open-source code HemeLB.
View Article and Find Full Text PDFJ Craniofac Surg
September 2025
Department of Craniomaxillofacial Surgery, Peking Union Medical College, Chinese Academy of Medical Sciences, Plastic Surgery Hospital, Beijing, China.
Objective: We designed a new distractor pairing a bioabsorbable upper fixing plate fixed by bioabsorbable screws with a traditional titanium distractor to simplify the second surgery removing the distractor after mandibular distraction osteogenesis. The present study aims to evaluate its biomechanical properties using finite element method.
Materials And Methods: Ten computer-aided designed models simulating mandibles of 5 patients under 2 working conditions, the instance of distraction and mastication, were produced.