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This manuscript examines the effects of memory-dependent and fractional-order derivatives on a novel generalized piezo-thermo-elastic semiconductor model. The medium is homogenous and orthotropic, subjected to photo-thermal excitation. The governing equations include fractional-order parameters, relaxation time, time delay, and kernel function tailored to specific problem requirements. Normal mode method use to solve the equations, yielding analytical expressions. Graphical representations show physical field distribution across various fractional-order parameters, kernel functions, time delay, and frequency values. This study has the potential to advance precise model development and future simulations. [ABSTRACT FROM AUTHOR]

This study uses the triple-phase lag model to investigate how higher-order fractional order and memory-dependent derivatives affect reflection at the free surface of an orthotropic piezo-thermoelastic medium. The performance of both kinds of derivatives is studied using the normal mode analysis technique. Four different types of coupled reflected plane waves are identified and explore the impact of various parameters, fractional order parameter, kernel function, the higher-order time differential fractional, and memory-dependent heat conduction parameters on energy distribution with respect to the angle of incidence. The results are presented graphically, providing numerical data for reflected waves, amplitude, and energy ratios. [ABSTRACT FROM AUTHOR]

In the context of the triple-phase lag model, comparison studies are conducted between the memory-dependent derivative and fractional order derivative on the propagation of plane waves in a half-space of initially stressed transversely isotropic piezothermoelastic material. The coupled governing equations of the considered model involving relaxation time, time delay, fractional order parameter, and kernel function are selected according to specific problems and solved using the normal mode analysis technique and obtaining the analytical expression. The non-dimensional temperature, displacement, electrical displacements, and stresses at different values of the fractional order parameter and time delay factor are obtained graphically. [ABSTRACT FROM AUTHOR]

We tested composite tracheal grafts (CTG) composed of a partially decellularized tracheal graft (PDTG) combined with a 3-dimensional (3D)-printed airway splint for use in long-segment airway reconstruction. CTG is designed to recapitulate the 3D extracellular matrix of the trachea with stable mechanical properties imparted from the extraluminal airway splint. We performed segmental orthotopic tracheal replacement in a mouse microsurgical model. MicroCT was used to measure graft patency. Tracheal neotissue formation was quantified histologically. Airflow dynamic properties were analyzed using computational fluid dynamics. We found that CTG are easily implanted and did not result in vascular erosion, tracheal injury, or inflammation. Graft epithelialization and endothelialization were comparable with CTG to control. Tracheal collapse was absent with CTG. Composite tracheal scaffolds combine biocompatible synthetic support with PDTG, supporting the regeneration of host epithelium while maintaining graft structure.

Decellularized tracheal scaffolds offer a potential solution for the repair of long-segment tracheal defects. However, complete decellularization of trachea is complicated by tracheal collapse. We created a partially decellularized tracheal scaffold (DTS) and characterized regeneration in a mouse model of tracheal transplantation. All cell populations except chondrocytes were eliminated from DTS. DTS maintained graft integrity as well as its predominant extracellular matrix (ECM) proteins. We then assessed the performance of DTS in vivo. Grafts formed a functional epithelium by study endpoint (28 days). While initial chondrocyte viability was low, this was found to improve in vivo . We then used atomic force microscopy to quantify micromechanical properties of DTS, demonstrating that orthotopic implantation and graft regeneration lead to the restoration of native tracheal rigidity. We conclude that DTS preserves the cartilage ECM, supports neo-epithelialization, endothelialization and chondrocyte viability, and can serve as a potential solution for long-segment tracheal defects.

This research article presents an analysis of the behavior of an initially stressed monoclinic piezothermoelastic half-space based on memory-dependent three-phase lags heat transfer law (MPS) underlying a thermoelastic half-space (TS) with subject to the hyperbolic two-temperature (H2T), classical two-temperature (C2T), and without two-temperature (W2T) models. By applying the normal mode approach, calculate the amplitude ratios and further utilize them to obtain the waves' energy ratios and interaction energy. The effect of memory-dependent derivatives (MDD), initial stresses, various kernel functions, and two temperature factors on the variation of energy ratios with incidence angle are graphically shown. The findings of this study have the potential to optimize material design, enhance seismic imaging techniques, improve thermal management in machinery, develop renewable energy systems, and facilitate materials characterization across diverse industries. [ABSTRACT FROM AUTHOR]

This article presents a mathematical framework that characterizes a transversely isotropic piezo-visco-thermoelastic medium within the context of the dual-phase lags heat transfer law (PVID) applied to an elastic medium (ES). Specifically, the study investigates the propagation of plane waves within the elastic medium and their interaction with the imperfect interface of the ES/PVID media. This interaction results in two waves reflecting back into the elastic medium and four waves propagating through the piezo-visco-thermo-elastic medium. The research explores the distribution of energy between the reflected and transmitted waves by analyzing amplitude ratios at the boundary interfaces, considering factors such as phase delays, viscosity effects, and wave frequency. The study illustrates the influence of boundary stiffness and viscosity parameters on these energy ratios through graphical rePresentations. The study's findings are consistent with the principles of the energy balance law, and the research also delves into specific cases of interest. Overall, this investigation provides insights into wave behavior within complex media and offers potential applications across various fields. [ABSTRACT FROM AUTHOR]

This study introduces a two-dimensional thermoelastic model for a homogeneous isotropic half-space with double porosity underlying an inviscid liquid half-space featuring temperature variations. The model incorporates the three-phase lag (TPL) heat equation and reveals that in the solid half-space, four coupled longitudinal waves intertwine with one uncoupled transverse wave, while one mechanical wave ripples through the liquid half-space. The investigation highlights dispersion, attenuation, and other effects affected by the thermal properties and the presence of voids. Using plane wave solutions and boundary conditions at the interface, a concise expression for the frequency equation of the model has been derived. Furthermore, the magnitudes of the displacements in the solid half-space and liquid half-spaces, the temperature change, and the volume fractional fields at the interface have been precisely determined. In the graphical section, computer-simulated results of various wave profiles for magnesium crystal material have been generated for different heat conduction thermoelastic models. The study's implications span various fields, such as hydrology, engineering, ultrasonics, navigation, and electronics. [ABSTRACT FROM AUTHOR]

AbstractThis study presents a comprehensive approach to vibrational analysis in a size-dependent, orthotropic thermo-piezo-photo-electric semiconductor half-space under Moore–Gibson–Thompson (MGT) photo-thermoelasticity theory with memory-dependent derivatives. Following Eringen’s nonlocal elasticity theory, the governing equations for the considered material are derived. The normal mode technique is applied to investigate the photothermal excitation process. Focusing on the interface adjacent to the vacuum, the study considers plasma, thermal, and mechanical stress boundary conditions to determine fundamental physical quantities. Through a detailed exploration, this research examines the impact of various thermo-piezo-photo-electric models, time, nonlocal parameters, and spatial coordinates on different physical quantities. The effects are meticulously analyzed and visually represented through graphical illustrations. While the literature survey reveals numerous studies on vibrational analysis in thermo-piezo-photo-electric semiconductor mediums under different thermoelasticity theories, to the best of the authors’ knowledge, no research emphasizing vibrational analysis in a size-dependent thermo-piezo-photo-electric semiconductor medium has been conducted. Moreover, the effect of memory-dependent MGT photo-thermoelasticity theory on a size-dependent thermo-piezo-photo-electric semiconductor half-space has not been illuminated until now, significantly defining the novelty of the conducted research. [ABSTRACT FROM AUTHOR]

An important objective of science and technology education is the development of pupils' capacity for systems thinking. While in science education the term system relates mainly to structures and phenomena in the natural world, technology education focuses on systems designed to fulfill people's needs and desires: examples include systems to control the local environment, or the position or motion of objects. Despite the centrality of the system concept to technology and technology education, issues relating to the teaching and learning of systems within the technology curriculum have been little addressed. This paper explores some elemental structures common to technological feedback control systems, and highlights the relationships between the structural nature and the dynamic behavior of these systems. It is argued that the study of systems and control concepts in technology has the potential to promote higher learning skills such as interdisciplinary thinking and modeling, and an instructional framework for achieving this goal is proposed. Questions and research issues on the fostering of systems thinking in technology education are identified.