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The primary focus of the present contribution is to develop a new system of differential equations describing the nonlocal thermoelasticity theory. The problem deals with the thermoelastic interaction in a nonhomogeneous thermoelastic layer induced by absorbing penetrating laser radiation throughout its volume. The heat conduction equation has been formulated in the context of memory dependent three-phase lag model. The surfaces of the layer are thermally insulated and free of traction. Employing the integral Laplace transform technique, the solutions of the field quantities have been achieved in the transformed domain. The corresponding solutions in the space–time domain have been derived using the numerical inversion of the Laplace transform by Riemann-sum approximation technique. The numerical estimates of the field quantities have been depicted graphically to address the effects of nonlocality and memory effects on the temperature profile, displacement and stress components. The effect of the delay time, nonhomogeneity and various choices of linear and nonlinear kernel functions in the heat transport law have also been reported. [ABSTRACT FROM AUTHOR]

Motivated by the wide-band-gap semiconductor properties of Zn-monochalcogenides (Zn-X; X:S, Se and Te), especially for their crucial industrial applications, we use a first-principles approach to investigate the B3 (zinc blende type) to B1 (rock salt type) structural transitions in this series of compounds as a function of pressure and temperature. Under static conditions (i.e., T = 0 K), the transition pressure is found to steadily drop from ZnS to ZnTe via intermediate ZnSe. Our calculations within quasi-harmonic approximation yield negative Clapeyron slopes of the B3–B1 phase boundaries for all the three compounds, where ZnTe has the highest negative slopes. We also present a completely new set of calculations for the thermoelasticity of Zn-X phases in the temperature range 0–1100 K. This article then addresses how the B3–B1 phase transitions can influence the mechanical as well as electronic properties of Zn-X. This phase transition always results in a softening of their elastic constant C12; however, C11 and C44 get stiffened. The same structural transition switches a semiconductor to conductor-type electronically favorable transition, as inferred from their high-pressure electronic structure. Among the three Zn-X compounds, ZnTe becomes the most metallic phase following the B3–B1 transition. Our findings offer a novel explanation for the complete loss of semiconductor property of these monochalcogenides at elevated pressures. [ABSTRACT FROM AUTHOR]

Enlightened by the memory dependent derivative, the present study deals with a novel mathematical model of generalized thermoelasticity to investigate the transient phenomena due to the influence of the magnetic field and moving heat source in a rod in the context of three-phase lag theory of thermoelasticity based on Eringen's nonlocal elasticity. Both ends of the rod were fixed, and heat is insulated. Employing Laplace transform as a tool, the problem was transformed into the space-domain and solved analytically. Finally, solutions in the real-time domain was obtained by applying the inverse Laplace transform. Numerical calculation for temperature, displacement and stress within the rod was carried out and displayed graphically. The effect of the moving heat source speed, time instance, memory dependent derivative, magnetic field and nonlocality on temperature, displacement, and stress was studied. Finally, three animated were added for easy understanding of the effect of moving the heat source on the studied fields. As per authors concern, the concept of the animated has been presented for the first time in this kinds of literature till now. [ABSTRACT FROM AUTHOR]

The main concern of this article is to deal with the thermoelastic interaction in a functionally graded thermoelastic rod being enlightened by the memory-dependent derivative. This article investigates the transient phenomena due to the influence of an induced magnetic field of constant intensity and due to the presence of a moving heat source of constant velocity in the context of three-phase lag model of generalized thermoelasticity. Employing the Laplace and the Fourier transforms as tool, the problem has been constructed in the transformed domain. The inversions of the Fourier transform have been carried out using residual calculus whereas the numerical inversions of the Laplace transform have been performed employing the Riemann sum approximation method. Numerical computations for stress, displacement, and temperature within the rod are carried out and have been demonstrated graphically. The results also demonstrate how the nonhomogeneity parameter and the speed of the moving heat source influence the thermophysical quantities. It is observed that the temperature, thermally induced displacement, and stress of the rod are found to decrease at large source speed. Also, significant differences on the thermophysical quantities are revealed due to the influence of magnetic field, nonhomogeneity, and memory effect also. [ABSTRACT FROM AUTHOR]

In this retrospective study, the understanding of heat transport and temperature variations on the tissues of the patients with recurrent cervical cancer subjected to chemoradiation or neoadjuvant chemotherapy followed by surgery and radiotherapy has been studied in the light of Caputo–Fabrizio (CF) bio-heat transport law, in the context of Lord–Shulman (LS) model. The skin tissue is subjected to prescribed temperature and both ends of the tissue are thermally insulated. Laplace transform technique is implemented to solve the governing equations. The influences of CF order and moving heat source velocity on the temperature of skin tissues and the thermal injuries are precisely investigated. The thermal injuries to the tissue are assessed by the denatured protein range using the current formulation in which the numerical inversion of the Laplace transform is carried out using Zakian methods. The numerical outcomes of thermal injuries and temperatures have been represented graphically. Excellent predictive capability is demonstrated for identification of appropriate procedure to select different orders of CF derivative to reach effective heating in hyperthermia treatment. [ABSTRACT FROM AUTHOR]

The vibration analysis of elastic medium is very important along with the miniaturization of the device and wide application of ultra-fast lasers, where size effect on heat conduction and elastic deformation increase and classical theory of thermoelastic coupling does not hold any more. Due to these, size-dependent thermoelastic model have been introduced for higher order simple material to adopt both the size effect of heat conduction and elasticity with the aids of extended irreversible thermodynamics and generalized free energy. Keeping this in mind, the present analysis reports the effect of ultra-short-pulsed laser heating in coupled thermoelastic vibration of a microscale ribbon resonator. The heat transport law of the current problem is defined by incorporating the three-phase-lag heat transport law in the context of Caputo–Fabrizio (CF) derivative. Finite sinusoidal Fourier and Laplace transform techniques have been employed to determine the lateral vibration of the ribbon and the temperature increment within the microscale ribbon. The result provides the direction how the nonlocality and size-dependence can control the vibration analysis and some excellent predictive capability have been demonstrated due to the presence of energy absorption depth and the order of CF derivative also. [ABSTRACT FROM AUTHOR]

The model of the equations of generalized thermoelasticity based on the Lord–Shulman's theory with nonlocal elasticity effect is used to study the photothermal waves in a semiconducting medium. The exact expressions for the displacement components, temperature, carrier density, and stress components are obtained by using normal mode analysis. Numerically simulated results are obtained and presented graphically for silicon. The comparisons are shown graphically to explore the effects of the time and the elastic nonlocal parameter on the different physical quantities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Designing drug-free polyvinyl alcohol coated stable silver triangular nano-prisms (PVA-SNT). • Computational simulation of optical and photothermal properties with high in vivo experimental similarity. • Stable PVA-SNT enables photoacoustic imaging-guided photothermal therapy of breast cancer. • PVA-SNT exhibits enhanced photostability and high photothermal conversion efficiency. The advanced features of plasmonic nanomaterials enable initial high accuracy detection with different therapeutic intervention. Computational simulations could estimate the plasmonic heat generation with a high accuracy and could be reliably compared to experimental results. This proposed combined theoretical-experimental strategy may help researchers to better understand other nanoparticles in terms of plasmonic efficiency and usability for future nano-theranostic research. To develop innovative computationally-driven approach to quantify any plasmonic nanoparticles photothermal efficiency and effects before their use as therapeutic agents. This report introduces drug free plasmonic silver triangular nanoprisms coated with polyvinyl alcohol biopolymer (PVA-SNT), for in vivo photoacoustic imaging (PAI) guided photothermal treatment (PTT) of triple-negative breast cancer mouse models. The synthesized PVA-SNT nanoparticles were characterized and a computational electrodynamic analysis was performed to evaluate and predict the optical and plasmonic photothermal properties. The in vitro biocompatibility and in vivo tumor abalation study was performed with MDA-MB-231 human breast cancer cell line and in nude mice model. The drug free 140 μg∙mL−1 PVA-SNT nanoparticles with 1.0 W∙cm−2 laser irradiation for 7 min proved to be an effective and optimized theranostic approach in terms of PAI guided triple negative breast cancer treatment. The PVA-SNT nanoparticles exhibits excellent biosafety, photostability, and strong efficiency as PAI contrast agent to visualize tumors. Histological analysis and fluorescence-assisted cell shorter assay results post-treatment apoptotic cells, more importantly, it shows substantial damage to in vivo tumor tissues, killing almost all affected cells, with no recurrence. This is a first complete study on computational simulations to estimate the plasmonic heat generation followed by drug free plasmonic PAI guided PTT for cancer treatment. This computationally-driven theranostic approach demonstrates an innovative thought regarding the nanoparticles shape, size, concentration, and composition which could be useful for the prediction of photothermal heat generation in precise nanomedicine applications. [ABSTRACT FROM AUTHOR]

The vibration of elastic micro-beam is of major significance due to wide applications of ultra-fast lasers, where size effect on heat conduction and elastic deformation increase and classical theory of thermoelastic coupling does not hold any more. Accordingly, the size-dependent thermoelastic model has been developed to deal with higher-order simple material to adopt both size effect of heat conduction and elasticity with the aids of extended irreversible thermodynamics and generalized free-energy. This survey demonstrates the effect of ultra-short-pulsed laser heating in the problem of coupled thermoelastic vibration of a microscale resonator, in which, the non-local heat transport equation is drafted in an integral form of a common derivative on a slipping interval by incorporating the three-phase-lag memory-dependent heat transfer in the context of two-temperature theory. Laplace transform and finite sinusoidal Fourier transform techniques have been employed to determine the lateral vibration of the beam and the scaled thermal moment within the beam. According to the graphical representations corresponding to the numerical results, conclusions about the new theory is constructed. Specific attention is paid to study the effect of thermal non-local parameter, energy absorption depth, memory-dependent derivative, the two-temperature parameter and delay time also. [ABSTRACT FROM AUTHOR]

This study represents an innovative approach to construct multi-functional nanoplatforms for cancer diagnosis and therapy by combining hyaluronic acid (HA) with iron-platinum nanoparticles (FePt NPs). These HA-coated FePt NPs, referred to as FePt@HA NPs, demonstrated remarkable biocompatibility, high absorption, and excellent light-to-heat conversion properties in the near-infrared (NIR) region, making them ideal candidates for photothermal therapy (PTT). In vitro studies revealed their effective cancer cell eradication under NIR laser irradiation, while in vivo experiments on mice showcased their superior heating capabilities. Moreover, FePt@HA NPs exhibited a distinct and strong photoacoustic (PA) signal, facilitating enhanced and precise intra-tumoral PA imaging. Our results highlight the potential of FePt@HA NPs as promising photothermal agents for future PTT applications. They offer high selectivity, precision, and minimal side effects in cancer treatment, along with their valuable PA imaging application for tumor localization and characterization. • FePt@HA NPs have the ability for PTT and PAI. • HA enhances the uptake of FePt@HA NPs into breast cancer cells. • FePt@HA NPs have good photothermal conversion and photothermal stability. [ABSTRACT FROM AUTHOR]

This study proposes a computationally efficient approach about the dynamic response of a homogeneous, transversely isotropic, thermoelastic micro-beam resonator subjected to time-dependent thermal loading. Due to the shortcomings of power law distributions in fractional derivatives, the usage of some other forms of derivatives with few other kernel functions are proposed. With this motivation, the heat transport equation is defined in an integral form of a common derivative on a slipping interval by incorporating the three-phase-lag memory-dependent heat transfer which is modeled based on Euler-Bernoulli beam theory. The beam is assumed to be clamped-clamped conditions on its axial ends. Employing the Laplace transform technique, the analytical solutions have been obtained. Further, incorporating residual calculus, the inversion of the transformed solutions are performed. The analytical expressions for the deflection has been computed numerically for a Silicon micro-beam using Maple software. The new approach is able to portray material heterogeneities and the non-locality of the new kernel allows the full describing of the memory within structure and media with different scales, which cannot be described by classical fractional derivative and also that of the memory-dependent derivative. [ABSTRACT FROM AUTHOR]

The present article is aimed at studying the effect of an induced magnetic field in an initially stressed homogeneous, isotropic, thermoelastic half-space. The corresponding mathematical modeling has been formulated in the context the memory-dependent heat transport equation in the context of three-phase lag model of generalized thermoelasticity involving two-temperature theory. The bounding plane of the medium is subjected to different types of prescribed temperature and variable mechanical loading. Employing the Laplace transform, the analytical results for the distributions of the thermophysical quantities have been derived and the corresponding vector-matrix differential equation is solved with the help of state space approach. The numerical inversion of the Laplace transform is carried out with the help of an efficient and pragmatic algorithm based on the Riemann-sum approximation technique. Numerical computations for a copper material is performed and have been demonstrated graphically. The result provides a motivation to investigate the problem and draw conducting remarks due to the influence of the magnetic field, memory effect and time-delay parameter also. [ABSTRACT FROM AUTHOR]

The objective of the present study is to formulate the bio-heat model to study the variations of temperature profile and thermal damages within a spherical living tissue subjected to a thermal therapy, whose outer surface is thermally insulated. The heat conduction equation is formulated in the context of convolution-type Dual-phase (DP) lag memory-dependent derivative, having kernels to be power functions, from which, the Lord–Shulman model can be obtained as a particular case. The Laplace transform technique is implemented to solve the governing equations. The influences of the memory-dependent derivative and effect of time-delay parameters on the temperature of skin tissues and the thermal injuries are precisely demonstrated. The thermal injuries of the tissue are assessed by the denatured protein range. The numerical inversion of the Laplace transform is performed with the help of Zakian methods. The numerical outcomes of thermal injuries and temperatures have been represented graphically. Excellent predictive capability is demonstrated to identify an appropriate therapy to select different kernel functions for effective heating in hyperthermia treatment. Significant effect of the thermal therapy is reported due to the effect of delay time also. [ABSTRACT FROM AUTHOR]

The analysis of fracture is very important along with the miniaturization of the device and wide application of ultra-fast lasers, where size effect on heat conduction and elastic deformation increase and classical theory of thermoelastic coupling does not hold any more. Due to these, size-dependent thermoelastic model have been introduced for higher order simple material to adopt both the size effect of heat conduction and elasticity with the aids of extended irreversible thermodynamics and generalized free energy. With this motivation, the present study is now formulated to provide the nonlocal phenomena of a homogeneous, isotropic infinite space weakened by a finite linear mode I crack. The boundary of the crack is subjected to prescribed temperature and stress. The governing equations have been solved on employing the Laplace and the Fourier transforms, which reduces to four dual integral equations, the solution of which is equivalent to solving the Fredholm's integral equation of the first kind. The Bellman method has been used to compute numerical inversion of the Laplace transform. The result provides the direction how the nonlocality and size-dependence can control the fracture and what is the significant effect of various kernel functions and the effect of memory is also reported. [ABSTRACT FROM AUTHOR]

The current paper has been presented to illustrate the thermoelastic vibration of a rotating microbeam based on generalized thermoelasticity theory, taking into account Euler–Bernoulli's assumptions. Using Hamilton's principle, the equation of motion of the initially stressed rotating microbeams has been derived. The microbeam is exposed to femtosecond laser pulses and sinusoidal varying heat. The Laplace transform technique is applied to obtain an analytical solution to the field variables. The influence of properties of various parameters, such as axial load, laser pulse duration, angular velocity, and material variation on the thermal and elastic waves of the rotating microbeam has been displayed graphically and discussed in detail. [ABSTRACT FROM AUTHOR]

In the present analysis, the bio-heat equation has been studied in the context of memory responses which is defined in the form of convolution having kernels as power functions. The heat transport equation for this problem involving the memory-dependent derivative on a slipping interval in the context of Dual-phase (DP) lag model, which is used to study the thermal damage within the graded spherical skin tissue during the thermal therapy, whose outer surface is thermally insulated. Laplace transform technique is implemented to solve the governing equations. The influences of the memory-dependent derivative and time-dependent moving heat source velocity on the temperature of skin tissues and the thermal injuries are precisely investigated. The thermal injuries to the tissue are assessed by the denatured protein range using the current formulation in which the numerical inversion of the Laplace transform is carried out using Zakian method. The numerical outcomes of thermal injuries and temperatures have been represented graphically. Excellent predictive capability is demonstrated for identification of appropriate procedure to select different kernel functions to reach effective heating in hyperthermia treatment. The significant effect of the thermal therapy is reported due to the effect of nonhomogeneity and delay time also. [ABSTRACT FROM AUTHOR]

In this paper, a general solution for the propagation of plane waves in the generalized piezo-thermoelastic medium for the two-dimensional problem under the different thermoelastic theories is investigated. We have included Lord-Shulman (L-S) and dual-phase lag (DPL) and three-phase lag (TPL) theories. The normal mode analysis is used to obtain the exact expressions for the considered variables. The results of the physical quantities have been illustrated graphically to study the effect of different kernel of memory dependent derivative along with memory dependent derivative is not used, the effect of delay times of memory dependent derivative for three-phase-lag (TPL) and finally comparisons between (L-S), (DPL) and (TPL) theories have been made in all the distribution. [ABSTRACT FROM AUTHOR]

This article highlights on the study of coupled plasma, thermal and elastic waves within an orthotropic infinite semiconducting medium in context of photothermal transport process having a spherical cavity under two-temperature theory. The memory-dependent heat transport equation for the present problem is involving the two-temperature dual-phase (DP) lag model of generalized thermoelasticity. The inner boundary of the cavity is stress free and is subjected to an exponentially decaying pulse. Moreover, the carrier density is prescribed on the boundary in terms of the recombination velocity. Employing the Laplace transform as tool, the analytical results for the distributions of the thermophysical quantities have been derived. The numerical inversion of the Laplace transform is carried out using a suitable scheme based on the Riemann-sum approximation technique. Numerical computations for an orthotropic semiconductor are performed and have been demonstrated graphically. The results also demonstrate the effect of coupling between plasma, thermal and elastic waves due to the presence of several kernel functions and response of memory effect. Also, significant differences on the thermophysical quantities are revealed due to the influence of two-temperature parameter, memory effect and time-delay parameter. [ABSTRACT FROM AUTHOR]

This present study deals with a novel mathematical model of generalized thermoelasticity in a fiber-reinforced, isotropic unbounded thermoelastic solid due to the presence of a continuous line heat source under the influence of magnetic field. The derivative is defined in an integral form of a common derivative on a slipping interval by incorporating memory-dependent heat transfer. Employing both Laplace and Hankel transforms as tools, analytical results for distributions of different fields have been derived with the help of potential function approach. The inversion of Hankel transform is performed analytically, whereas the numerical inversion of Laplace transform is carried out employing Zakian method and the method based on Fourier series expansion technique. According to the graphical representations corresponding to the numerical results, conclusions about the new theory to exhibit the significance of the kernel functions and the time-delay parameter is constructed. The significant differences of the two different numerical schemes have also explained. Excellent predictive capability is demonstrated due to the presence of memory-dependent derivative and presence of reinforcement and magnetic field. Also, significant differences due to the choice of linear and nonlinear kernels in the heat equation is elaborated. [ABSTRACT FROM AUTHOR]

This article focuses on studying the coupled plasma, thermal, elastic waves of a semiconductor in context of photothermal transport process with cylindrical cavity under the influence of magnetic field subjected to memory-dependent Dual-phase lag heat equation. The surface of the cavity is subjected to exponentially decaying pulse and prescribed carrier density. Employing Laplace transform, the analytical results for distributions of the thermophysical quantities have been derived. The numerical inversion of the Laplace transform is carried out using Riemann-sum approximation technique. Significant differences on the thermophysical quantities are revealed due to the influence of magnetic field, memory effect and time-delay parameter. Communicated by Marat Z. Dosaev. [ABSTRACT FROM AUTHOR]

In recent years, suitable bioactive materials coated nanoparticles have attracted substantial attention in the field of biomedical applications. The present study emphasizes experimental details for the synthesis of boiling rice starch extract (BRE) coated iron oxide nanoparticles (IONPs) to treat cancer by photoacoustic imaging (PAI)-guided chemo-photothermal therapy. The solvothermal method was used to synthesize IONPs. The physical immobilization method helps to coat BRE-loaded doxorubicin (DOX) molecules on the iron oxide surface. In vitro drug release was estimated in basic (pH 9.0), neutral (pH 7.2), and acidic (pH 4.5) media for varying time periods using ultraviolet-visible spectroscopy. The chemical and physical properties of the synthesized spherical BRE-IONPs were characterized using sophisticated analytical instrumentation. A magnetic saturation experiment was performed with BRE-IONPs for evaluating possible hyperthermia in targeted drug delivery. The biological activity of the synthesized BRE-IONPs was investigated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and acridine orange/propidium iodide fluorescence cell viability study. BRE-IONPs showed excellent photothermal stability, with a high photothermal conversion efficiency (η = 29.73%), biocompatible property, and high near-infrared region absorption for PAI-guided PTT treatment. This study will provide a better understanding of rice starch as a suitable bioactive coating material for possible theranostic applications. • A facile synthesis technique of natural polymer boiling rice extract-coated IONPs is studied for biomedical applications. • The drug loading (~78% DOX) with pH regulated releasing property (~46% DOX) makes DOX-BRE-IONPs a promising anticancer agent. • The synthesized DOX-BRE-IONPs acts as an excellent photothermal agent with a heat conversion efficiency of ~29.73%. • DOX-BRE-IONPs have potential photoacoustic imaging contrast efficiency for bio-imaging applications. • DOX-BRE-IONPs could be a promising multifunctional imaging-guided chemo-photo-thermal therapeutic agent for cancer treatment. [ABSTRACT FROM AUTHOR]

This present survey deals with a novel mathematical model of generalized thermoelasticity which investigates the transient phenomena in a two‐dimensional problem for a transversely isotropic thick plate having a heat source. The upper surface of the plate is stress‐free with prescribed surface temperature while the lower surface of the plate rests on a rigid foundation and is thermally insulated. The study is carried out in the context of the three‐phase‐lag thermoelastic model. The governing equations for displacement and temperature fields are obtained in the Laplace‐Fourier transform domain by applying the Laplace and Fourier transform techniques. The inversion of double transform has been done numerically. The numerical inversion of the Laplace transform is done by using a method based on the Fourier series expansion technique. The numerical estimates of the quantities of physical interest are obtained and depicted graphically. The effect of the memory‐dependent derivative on the solutions has been studied. [ABSTRACT FROM AUTHOR]

In the present analysis, the bio-heat equation has been studied in the context of memory responses which is defined in the form of convolution having kernels as power functions. The heat transport equation for this problem involving the memory dependent derivative on a slipping interval in the context of Lord-Shulman (LS) model is formulated. The thermal damage within the skin tissue during the thermal therapy is also reported in the literature. Laplace transform technique is implemented to solve the governing equations. The influences of the memory-dependent derivative and time-dependent moving heat source velocity on the temperature of skin tissues and the thermal injuries are precisely investigated. The thermal injuries to the tissue are assessed by the denatured protein range using the current formulation in which the numerical inversion of the Laplace transform is carried out using Zakian methods. The numerical outcomes of thermal injuries and temperatures have been represented graphically. Excellent predictive capability is demonstrated for identification of appropriate procedure to select different kernel functions to reach effective heating in hyperthermia treatment. Significant effect of the thermal therapy is reported due to the effect of delay time also. [ABSTRACT FROM AUTHOR]

The main concern of this article is to deal with the thermoelastic interaction in a thick plate subjected to a moving heat source and being enlightened by memory-dependent derivative (MDD). Due to the shortcomings of power law distributions in Taylor's series, some other forms of derivatives with few other kernel functions have been proposed. The present literature deals with a novel mathematical model of generalized thermoelasticity to investigate the transient phenomena for a thermoelastic thick plate in which, the memory-dependent heat transport equation involves the Dual-phase (DP) lag model of generalized thermoelasticity. Employing the Laplace transform and Fourier transforms, the analytical results for the distributions of the thermophysical quantities have been derived. The numerical inversions of the respective transforms have been carried out using a suitable numerical scheme based on the Fourier series expansion technique. Numerical computations for stress, displacement and temperature within the plate have been carried out and have been demonstrated graphically. The results also demonstrate how the heat source moves with time and influences the thermophysical quantities according to its respective position by that time. Also, significant differences on the thermophysical quantities are revealed due to the influence of magnetic field, memory effect and time-delay also. [ABSTRACT FROM AUTHOR]

In the application of pulsed laser heating, such as laser hardening of metallic surfaces, conduction limited process is the dominant mechanism during the laser–workpiece interaction. As a consequence, time unsteady analysis of this problem becomes necessary. The present study examines the effect of ultra‐short‐pulsed laser heating in coupled thermoelastic vibration of a microscale beam resonator. The heat transport equation for the current problem is defined by incorporating the three‐phase‐lag heat transport law in the context of Caputo‐Fabrizio (CF) derivative. Finite sinusoidal Fourier and Laplace transform techniques have been employed to determine the lateral vibration of the beam and the temperature increment within the microscale beam. According to the graphical representations corresponding to the numerical results, conclusions about the new theory is constructed. Excellent predictive capability is demonstrated due to the presence of energy absorption depth and the order of CF derivative also. [ABSTRACT FROM AUTHOR]

The design and synthesis of alternative biocompatible, luminescent bioimaging agent for application in diagnostics imaging and preventive medicine is very important for the future of biomedicine. With an advanced flexible structure of hydroxyapatite (HAp), rare earth ions (Gd3+, Eu3+) were doped to achieve an enhanced luminescent optical property. A facile wet co-precipitation method was employed to dope Gd3+, and Eu3+ on host HAp structure (Eu x -Gd x -HAp). Different sophisticated characterization instruments, such as powder X-Ray diffraction, Fourier transformed infrared (FTIR) spectroscopy, micro Raman spectroscopy, Thermogravimetric-differential thermal analysis (TG-DTA), Brunauer-Emmett-Teller (BET) surface area analysis confirms the hexagonal crystal structure, functional groups, high thermal stability, with large surface area and average pore size. The optical properties were measured by diffusive reflectance spectroscopy (DRS), photoluminescence (PL) spectroscopy, and fluorescence imaging. The enhanced luminescence could be observed due to "Gd–Eu" co-doping, which causes energy transfer ( 6 I J of Gd 3+ → 5 H J of Eu 3+ ) under 273 nm excitation with possible combination effect of the cooperative up-conversion and subsequent energy transfer under 394 nm excitation respectively. The in vitro study confirms the intracellular nontoxic behavior of Eu x -Gd x -HAp nanocrystals with good biocompatibility. Further in vivo studies with Eu x -Gd x -HAp nanocrystals confirms the cell labelling and in vivo imaging capabilities. The synthesized biocompatible, nontoxic Eu x -Gd x -HAp nanomaterials has the potential to act as a luminescence enhanced contrast agent for biomedical fluorescent imaging applications. [ABSTRACT FROM AUTHOR]

The present study is concerned with the reflection and propagation of thermoelastic plane waves from the stress‐free and thermally insulated surface of a homogeneous, isotropic thermally conducting elastic half‐space in the frame of modified Green–Lindsay theory of generalized thermoelasticity with two‐temperature (2TMGL). The thermoelastic coupling effect creates two types of coupled longitudinal waves which are dispersive as well as exhibit attenuation. Different from the thermoelastic coupling effect, there also exists one independent vertically shear‐type (SV‐type) wave. In contrast to the classical Green–Lindsay (GL) and Lord–Shulman (LS) theories of generalized thermoelasticity, the SV‐type wave is not only dispersive in nature but also experiences attenuation. Analytical expressions for the amplitude ratios and their respective energy ratios for reflected thermoelastic waves are determined when a coupled longitudinal wave is made incident on the free surface. The paper concludes with the numerical results on the phase speeds, amplitude ratios and their respective energy ratios for specific parameter choices. Various graphs have been plotted to analyze the behavior of these quantities. The characteristics of employing the 2TMGL model are discussed by comparing the numerical results obtained for the present model with those obtained in case of the two‐temperature Green–Lindsay (2TGL) and two‐temperature Lord–Shulman (2TLS) models. [ABSTRACT FROM AUTHOR]

This article constructs a new model of nonlocal thermoelasticity which resolves a dynamical problem of a homogeneous, isotropic infinite space weakened by a finite linear mode I crack. The boundary of the crack is being subjected to a prescribed temperature distribution and stress. In the context of three-phase lag model of generalized thermoelasticity, the governing equations have been solved employing the Laplace and the Fourier transforms, which reduces to four dual integral equations, the solution of which is equivalent to solving the Fredholm's integral equation of the first kind. These integral equations have been solved employing the Maple software package, while the numerical inversion of the Laplace transform is carried out with the help of Bellman method. Numerical computations for a copper material are performed and demonstrated graphically. The results provide a motivation to further investigate the problem and draw concluding remarks due to the influence of nonlocality also. [ABSTRACT FROM AUTHOR]

Diagnosis and imaging play an essential key role in primary detection, screening, and image-guided smart nanomedicine for healthcare solutions. This study illustrates the successful fabrication of luminescent lanthanide (erbium)-doped hydroxyapatite (Er-HAp) by one step facile wet-chemical precipitation method. The chemical compositions, morphology, optical, and biological properties were systematically characterized using relevant different structural, compositional analytical instrumentation and cytotoxicity assays. After erbium doping, synthesized luminescent nano-structured materials exhibited elongated morphology, with well dispersed <50 nm size distribution. The photoluminescence (PL) study confirmed three emission bands assigned to 4 F 3/2 → 4 I 15/2 (purple), 4 F 7/2 → 4 I 15/2 (blue), and 4 S 3/2 → 4 I 15/2 (green) transition states, respectively. In vitro bioactivity and optical imaging studies conducted in osteoblast like MG-63 cells confirmed the nontoxic luminescent behavior of the synthesized nanomaterials. [ABSTRACT FROM AUTHOR]

Enlightened by the Caputo fractional derivative, the present study deals with a novel mathematical model of generalized thermoelasticity to investigate the transient phenomena due to the influence of magnetic field and moving heat source in a rod in the context of three-phase lag (TPL) theory of thermoelasticity. Both ends of the rod are fixed and heat insulated. Employing Laplace transform as a tool, the problem has been transformed into the space-domain and solved analytically. Finally, solutions in the real-time domain are obtained by applying the inverse Laplace transform. Numerical calculation for stress, displacement, and temperature within the rod is carried out and displayed graphically. The effect of moving heat source speed on temperature, stress, and temperature is studied. It is found from the distributions that the temperature, thermally induced displacement and stress of the rod are found to decrease at large source speed. For the better understanding of the effect of moving heat source on all the distributions, three animations are added. [ABSTRACT FROM AUTHOR]

The Fractional derivative is a widely accepted theory to describe physical phenomena and the processes with memory effects which is defined in the form of convolution having kernels as power functions. Due to the shortcomings of power-law distributions, some other forms of derivatives with few other kernel functions are proposed. This present study deals with a novel mathematical model of generalized thermoelasticity to investigate the transient phenomena due to the influence of the magnetic field and moving heat source in a thermoelastic rod in the context of the Lord–Shulman (LS) theory of generalized thermo-visco-elasticity. Both ends of the rod are fixed and are thermally insulated. Employing the Laplace transform as a tool, the problem has been transformed into the space-domain and solved analytically. Finally, solutions in the real-time domain are obtained on applying the numerical inversion of the Laplace transform, which has been carried out employing the Riemann sum approximation method. Numerical computations for stress, displacement, and temperature within the rod is carried out and have been demonstrated graphically. The results also demonstrate how the speed of the moving heat source influences the thermophysical quantities. It is observed that the temperature, thermally induced displacement and stress of the rod are found to decrease at large source speed. Also, significant differences in the thermophysical quantities are revealed due to the influence of the magnetic field and memory effect [ABSTRACT FROM AUTHOR]

To achieve optimum functionality and mechanical properties of advanced manufacturing-based scaffolds for biomedical application, it is important to study their mechanical strength by 3D-printing at different orientations. This study examined the effects of printing at different orientations on the mechanical properties of synthesized 3D-polylactic acid (PLA) and hydroxyapatite-modified PLA (PLA-HAp) scaffolds. A total number of 30 samples were printed in three orientations on the XY plane: 0°, 45°, and 90°. Finite element modeling and simulation was employed to identify the strongest scaffold in terms of compression strength, which is the primary criterion for load bearing bone tissue scaffolds. These findings indicate that 3D-printing at an orientation of 90° on the XY plane resulted in a scaffold with the highest compression strength. Moreover, the fabricated PLA scaffolds showed very poor cell attachment and proliferation on their surface, which is not suitable for their biomedical application. This study additionally showed the optimization of a very simple post-fabrication modification technique with nano HAp for better cell attachment and proliferation with enhanced mechanical properties. The post-fabrication modification of PLA scaffolds by nano-HAp results in excellent cell attachment property with enhanced mechanical strength and stability of up to 47.16% for 90° 3D-printed PLA-HAp scaffolds. [ABSTRACT FROM AUTHOR]

Enlightened by the Caputo fractional derivative, this study deals with a novel mathematical model of generalized thermoelasticity to investigate the transient phenomena due to the influence of magnetic field and moving heat source in a rod in the context of Lord–Shulman (LS) theory of thermoelasticity based on Eringen's nonlocal elasticity. Both ends of the rod are fixed and heat insulated. Employing Laplace transform as a tool, the problem has been transformed into the space domain and solved analytically. Finally, solutions in the real-time domain are obtained by applying the inverse Laplace transform. Numerical calculation for stress, displacement, and temperature within the rod is carried out and displayed graphically. The effects of moving heat source speed, time instance, memory-dependent derivative, magnetic field and nonlocality on temperature, stress, and temperature are studied. [ABSTRACT FROM AUTHOR]

Modeling and understanding heat transport and temperature variations within biological tissues and body organs are key issues in medical thermal therapeutic applications, such as hyperthermia cancer treatment. In the present analysis, the bioheat equation is studied in the context of memory responses. The heat transport equation for this problem involving the memory-dependent derivative (MDD) on a slipping interval in the context of three-phase (3P) lag model under two-temperature theory is formulated and is then used to study the thermal damage within the skin tissue during the thermal therapy. Laplace transform technique is implemented to solve the governing equations. The influences of the MDD and moving heat source velocity on the temperature of skin tissues are precisely investigated. The numerical inversion of the Laplace transform is carried out using Zakian method. The numerical outcomes of temperatures are represented graphically. Excellent predictive capability is demonstrated for identification of an appropriate procedure to select different kernel functions to reach effective heating in hyperthermia treatment. Significant effect of thermal therapy is reported due to the effect of delay time and the velocity of moving heat source as well. [ABSTRACT FROM AUTHOR]

The exponential growth of next generation sequencing (NGS) data has put forward the challenge for its storage as well as its efficient and faster analysis. Storing the entire amount of data for a particular experiment and its alignment to the reference genome is an essential step for any quantitative analysis of NGS data. Here, we introduce streaming access technique ' ParStream-seq ' that splits the bulk sequence data, accessed from a remote repository into short manageable packets followed by executing their alignment process in parallel in each of the compute core. The optimal packet size with fixed number of reads is determined in the stream that maximizes system utilization. Result shows a reduction in the execution time and improvement in the memory footprint. Overall, this streaming access technique provides means to overcome the hurdle of storing the entire volume of sequence data corresponding to a particular experiment, prior to its analysis. • Introduced a sequence streaming protocol called ParStream-seq which splits and access the bulk sequence data. • To overcome the hurdle of storing the entire volume of NGS data corresponding to a particular experiment. • Determined the 'optimal packet size' with a fixed number of reads and optimal number of sequence splits for streaming. • It facilitates parallel execution of alignment process and stores the results in the Hadoop Distributed File system (HDFS). [ABSTRACT FROM AUTHOR]

Following the link of work of He and Cao (2009, Math. Comput. Modell., 49(7-8), 1719-1720), we employ the theory of generalized thermoelasticity with dual-phase-lag (DPL) to study the transient phenomena in a thin slim strip due to a moving heat source. Both ends of the strip are assumed to be fixed and thermally insulated. Using Laplace transform as a tool, the problem has been transformed into the space-domain and solved analytically. Finally, solutions in the real-time domain are obtained by applying the inverse Laplace transform. Numerical calculation for stress, displacement, and temperature within the strip are carried out and presented graphically. The effect of moving heat source speed on temperature, stress, and displacement is studied. The temperature, displacement, and stress in the strip are found to be decreasing at large source speed. [ABSTRACT FROM AUTHOR]

This present work is devoted to the investigation of the transient phenomena for a fiber-reinforced medium with a cylindrical cavity in the context of the three-phase-lag model of generalized thermoelasticity with a new form of derivative of the Caputo–Fabrizio (CF) type in the heat transport equation, where the medium is under the action of an induced magnetic field. The Laplace transform is incorporated as a tool for the solution of the problem when the boundary of the cavity is exposed to harmonically varying heat with a constant angular frequency of thermal vibration. The numerical inversion of the Laplace transforms is computed using the Zakian method. Excellent predictive capability is demonstrated due to the presence of reinforcement, the angular frequencies on thermal vibrations, CF fractional parameter and magnetic field. [ABSTRACT FROM AUTHOR]

In the application of pulsed laser heating, such as the laser hardening of metallic surfaces, the conduction limited process is the dominant mechanism during the laser-workpiece interaction. As a consequence, time unsteady analysis of this problem becomes necessary. The present study examines the effect of ultra-short-pulsed laser heating in the problem of coupled thermoelastic vibration of a microscale beam resonator. Due to the shortcomings of power law distributions in fractional derivatives, the usage of some other forms of derivatives with some other kernel functions is proposed. With this motivation, the heat transport equation is defined in an integral form of a common derivative on a slipping interval by incorporating the three-phase-lag memory-dependent heat transfer. Finite sinusoidal Fourier and Laplace transform techniques are then employed to determine the lateral vibration of the beam and the temperature increment within the medium. According to the graphical representations corresponding to the numerical results, conclusions about the new theory are drawn. An excellent predictive capability is demonstrated due to the presence of the energy absorption depth, memory dependent derivative, and delay time. [ABSTRACT FROM AUTHOR]

Fabrication of nanostructured materials with multifunctional properties and improved biocompatibility have immense potential for biomedical applications. The novelty of this research is to synthesize nanostructured hollow hydroxyapatite (H-HAp) for enhanced drug delivery applications. The nano hollow structure synthesis mechanism involves the controlled precipitation of calcium and phosphate ions over a pre-synthesized nano carbon template, followed by calcination to eliminate the core carbon structure. The synthesized nano-structured H-HAp was analyzed to determine its chemical, elemental, structural, and morphological characteristics by different spectroscopic, gravimetric, and electron microscopy techniques. The potential advances of H-HAp nanoparticles in biological applications were studied by using MDA-MB-231 breast cancer cell lines, and drug kinetics experiments. The cytotoxicity and the efficacy of H-HAp as a drug carrier agent were studied by MTT and fluorescence staining assay. The comparative drug loading/releasing kinetics were studied using nanostructured H-HAp and HAp with the model drug doxorubicin (DOX) and bovine serum albumin (BSA) protein. The synthesized nanostructured materials show relatively enhanced drug (DOX = ∼53.33%) and protein (BSA = ∼43.06%) loading capacities compared to conventional HAp (DOX = ∼46% and BSA = ∼23.62%). The H-HAp nanostructured system shows a pH-dependent sustained in vitro release behavior of model drug molecules. The novelty of this study relies on its facile synthesis mechanism to fabricate a hollow nano HAp structure, which differs from limited reported articles based mostly on microstructure H-HAp for biomedical applications. [ABSTRACT FROM AUTHOR]

The primary steps of photoinduced electron transfer (PET) from N,N-dimethylaniline (DMA) to five coumarin dyes are studied in an anionic micelle [sodium dodecyl sulfate (SDS)] and a neutral micelle [triton X-100 (TX-100)] using femtosecond upconversion. The rate of PET in micelle is found to be highly nonexponential. In both the micelles, PET displays components much faster (∼10 ps) than the slow components (180–2900 ps) of solvation dynamics. The ultrafast components of electron transfer exhibit a bell-shaped dependence on the free energy change. This is similar to Marcus inversion. The rates of PET in TX-100 and SDS micelle are, in general, faster than those in cetyltrimethylammonium bromide (CTAB) micelle. In the SDS and TX-100 micelle, the Marcus inversion occurs at -ΔG0 ∼0.7 eV which is lower than that (∼1.2 eV) in CTAB micelle. Possible causes of variation of PET in different micelles are discussed. [ABSTRACT FROM AUTHOR]

Fluorescence resonance energy transfer (FRET) from coumarin 480 (C480) to fluorescein 548 (F548) in a sodium dioctyl sulfosuccinate (AOT) reverse micelle is studied by picosecond and femtosecond emission spectroscopy. In bulk water, at the low concentration of the donor (C480) and the acceptor (F548), no FRET is observed. However, when the donor (C480) and the acceptor (F548) are confined in a AOT reverse micelle very fast FRET is observed. The time constants of FRET were obtained from the rise time of the emission of the acceptor (F548). In a AOT microemulsion, FRET is found to occur in multiple time scales—3, 200, and 2700 ps. The 3 ps component is assigned to FRET in the water pool of the reverse micelle with a donor-acceptor distance, 16 Å. The 200 ps component corresponds to a donor-acceptor distance of 30 Å and is ascribed to the negatively charged acceptor inside the water pool and the neutral donor inside the alkyl chains of AOT. The very long 2700 ps component may arise due to FRET from a donor outside the micelle to an acceptor inside the water pool and also from diffusion of the donor from bulk heptane to the reverse micelle. With increase in the excitation wavelength from 375 to 405 nm the relative contribution of the FRET due to C480 in the AOT reverse micelle (the 3 and 200 ps components) increases. [ABSTRACT FROM AUTHOR]

Temperature dependence of solvation dynamics and fluorescence anisotropy decay of 8-anilino-1-naphthalenesulfonate (ANS) bound to a protein, bovine serum albumin (BSA), are studied. Solvation dynamics of ANS bound to BSA displays a component (300 ps) which is independent of temperature in the range of 278–318 K and a long component which decreases from 5800 ps at 278 K to 3600 ps at 318 K. The temperature independent part is ascribed to a dynamic exchange of bound to free water with a low barrier. The temperature variation of the long component of solvation dynamics corresponds to an activation energy of 2.1 kcal mol-1. The activation energy is ascribed to local segmental motion of the protein along with the associated water molecules and polar residues. The time scale of solvation dynamics is found to be very different from the time scale of anisotropy decay. The anisotropy decays are analyzed in terms of the wobbling motion of the probe (ANS) and the overall tumbling of the protein. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp), a well-known biomaterial, has witnessed a remarkable evolution over the years, transforming from a simple biocompatible substance to an advanced functional material with a wide range of applications. This abstract provides an overview of the significant advancements in the field of HAp and its journey towards becoming a multifunctional material. Initially recognized for its exceptional biocompatibility and bioactivity, HAp gained prominence in the field of bone tissue engineering and dental applications. Its ability to integrate with surrounding tissues, promote cellular adhesion, and facilitate osseointegration made it an ideal candidate for various biomedical implants and coatings. As the understanding of HAp grew, researchers explored its potential beyond traditional biomaterial applications. With advances in material synthesis and engineering, HAp began to exhibit unique properties that extended its utility to other disciplines. Researchers successfully tailored the composition, morphology, and surface characteristics of HAp, leading to enhanced mechanical strength, controlled drug release capabilities, and improved biodegradability. These modifications enabled the utilization of HAp in drug delivery systems, biosensors, tissue engineering scaffolds, and regenerative medicine applications. Moreover, the exceptional biomineralization properties of HAp allowed for the incorporation of functional ions and molecules during synthesis, leading to the development of bioactive coatings and composites with specific therapeutic functionalities. These functionalized HAp materials have demonstrated promising results in antimicrobial coatings, controlled release systems for growth factors and therapeutic agents, and even as catalysts in chemical reactions. In recent years, HAp nanoparticles and nanostructured materials have emerged as a focal point of research due to their unique physicochemical properties and potential for targeted drug delivery, imaging, and theranostic applications. The ability to manipulate the size, shape, and surface chemistry of HAp at the nanoscale has paved the way for innovative approaches in personalized medicine and regenerative therapies. This abstract highlights the exceptional evolution of HAp, from a traditional biomaterial to an advanced functional material. The exploration of novel synthesis methods, surface modifications, and nanoengineering techniques has expanded the horizon of HAp applications, enabling its integration into diverse fields ranging from biomedicine to catalysis. Additionally, this manuscript discusses the emerging prospects of HAp-based materials in photocatalysis, sensing, and energy storage, showcasing its potential as an advanced functional material beyond the realm of biomedical applications. As research in this field progresses, the future holds tremendous potential for HAp-based materials to revolutionize medical treatments and contribute to the advancement of science and technology. [Display omitted] • Hydroxyapatite a biomaterials journey to advanced functional materials. • The role of Hydroxyapatite in environmental remediation application. • The role of hydroxyapatite in photocatalysis application. • Hydroxyapatite applications as energy storage materials. • From medicine to industry: Hydroxyapatite's broad multifunctional scope. [ABSTRACT FROM AUTHOR]

The main idea of the present work is to extend Eringen's theory of nonlocal elasticity to generalized thermoelasticity with dual-phase-lag and voids. Then we study the propagation of time harmonic plane waves in an infinite nonlocal dual-phase-lag thermoelastic medium with voids. Three sets of coupled dilatational waves and an independent transverse wave may travel with distinct speeds through the medium. All these waves are found to be dispersive in nature. The coupled dilatational waves are damping, while the transverse wave is undamped in a certain range of the angular frequency. Coupled dilatational waves are found to be influenced by the presence of voids, thermal field and elastic nonlocal parameter, while the transverse wave is found to be influenced by the nonlocal parameter, but independent of void and thermal parameters. For a particular model, the effects of angular frequency, elastic nonlocality parameter, and some voids and thermal parameters on the wave speeds and damping coefficients of all the propagating waves have been studied numerically. Some comparisons are made between the results obtained for local and nonlocal cases. All the computed results have been depicted graphically and explained in details. [ABSTRACT FROM AUTHOR]

Enlightened by the Caputo fractional derivative, the present study deals with a novel mathematical model of generalized thermoelasticity to investigate the transient phenomena for a piezoelastic half-space due to the influence of a magnetic field in the context of the dual-phase-lag model of generalized thermoelasticity, which is defined in an integral form of a common derivative on a slipping interval by incorporating the memory-dependent heat transfer. The bounding plane of the medium is assumed to be stress free and subjected to a thermal shock. Employing the Laplace transform as a tool, the problem is transformed to the space domain, where the solution in the space–time domain is achieved by applying a suitable numerical technique based on Fourier series expansion technique. According to the graphical representations corresponding to the numerical results, conclusions about the new theory are constructed. Excellent predictive capability is demonstrated due to the presence of electric field, memory-dependent derivative and magnetic field. [ABSTRACT FROM AUTHOR]

This present study illustrates the processing and comprehensive characterization of biogenic hydroxyapatite (FB-HAp) biomaterial from fish bone (Tuna fish) in a facile single step thermal decomposition procedure. Fish bones were calcined at 1000 °C in an air atmosphere for 1 h. The obtained FB-HAp flakes were ball milled for 30 h at a unidirectional milling speed of 300 rpm. A well-established wet chemical process was obtained to synthesize HAp nanoparticles (C-HAp). The synthesized non-stoichiometric (Ca/P = 1.87) FB-HAp phases were identified by X-ray diffraction study and compared with C-HAp. The thermal properties were studied by thermogravimetric and differential thermal analysis. Raman spectroscopy and Fourier transform infrared spectroscopy confirmed the structural and functional groups of FB-HAp and C-HAp. The morphological and elemental analysis was performed by transmission electron microscopy, energy dispersive X-ray spectroscopy and Inductive coupled plasma (ICP) spectroscopy. The synthesized FB-HAp and C-HAp were mixed with 2% starch porogen and compacted with ∼200 MPa unidirectional pressure to obtained small pellet scaffolds. The obtained scaffolds were sintered at 1000 °C in an air atmosphere for 2 h and further used for cell attachment and proliferation study. The FB-HAp biomaterials showed non-toxic behavior with MG-63 osteoblast cell lines similar to C-HAp. Additionally, FB-HAp scaffold showed enhanced cellular attachment and proliferation on its surface. The in-depth chemical, structural, and morphological analysis suggest that fish bone could be a promising sustainable biogenic source of HAp for biomedical applications. • Facile synthesis of biogenic hydroxyapatite from waste tuna bones. • Comparative characterization of fish bone and chemically synthesized hydroxyapatite. • Possible mechanism for enhanced bioactivity of biogenic hydroxyapatite. • Scaffold fabrication and promising application for tissue engineering. [ABSTRACT FROM AUTHOR]

Abstract A rapid microwave assisted facile synthetic technique was adopted to load gold nanoparticles (Au) on hydroxyapatite (HAp) surface. HAp nanoparticles were primarily synthesized by wet precipitation technique and further used for gold loading and successive collagen coating for biomedical applications. The microwave-assisted controlled synthesis technique with three heating cycles allows the very fast growing of Au seeds over HAp facets. Different sophisticated analytical techniques and spectroscopic characterization were employed to confirm the structural, chemical, and morphological features. The synthesized different concentration "Au" loaded hetero nanostructures coated with collagen (Au–HAp–Col) optimized for drug (Doxorubicin: DOX) loading and releasing purposes for biomedical applications. The maximum drug-loading efficiency of ~58.22% and a pH responsive releasing of ~53% (at pH 4.5) was obtained for 0.1 wt% Au–HAp–Col nanoparticles. To study the cytotoxic effects from the hetero nanostructures, MG-63 osteoblast-like cells were exposed to different concentration ranges on Au–HAp, Au–HAp–Col, and DOX loaded Au–HAp–Col nanoparticles. The non-toxic and bioactive properties of the synthesized nanoparticle-fabricated scaffold promotes cellular attachment, growth, and proliferation. These results indicated that optimized Au–HAp–Col nanoparticles may be promising drug delivery and scaffold materials for multifunctional biomedical applications. [ABSTRACT FROM AUTHOR]

Abstract An innovative biomimetic approach has been employed for the synthesis of human and environmental friendly nanomaterials for biomedical application. The aim of this research is to study the structural analysis of biomimetic-synthesized gold (Au) and silver (Ag) nanoparticles loaded on pristine hydroxyapatite (HAp) and their potential advances in biomedical applications. The synthesized metal–hydroxyapatite nanoparticles’ structural and morphological characteristics were studied using X-ray diffraction (XRD), different spectroscopies (UV–vis, DRS, FTIR, zeta potential), BET surface area and pore size analyzer and electron microscopy (FE-TEM, FE-SEM). Biological activity was established using osteoblast-like MG-63 cell line and antibacterial tests with Escherichia coli (E. coli), which is one of the most common bacteria in the human body. Cell cytotoxicity test (MTT assay and fluorescence imaging with AO/PI staining) was conducted with MG-63 cells to study the toxicity of Au-HAp, Ag-HAp, and Au-Ag-HAp (bimetallic) nanoparticles. Antimicrobial studies have shown that all Ag-HAp nanoparticles have excellent in vitro antibacterial activity with E. coli. The present research investigates the structural stability and biocompatibility of Au-HAp, Ag-HAp, and Au-Ag-HAp nanoparticles, which may be the best materials to repair bone infection (osteomyelitis) and could be useful as a potential scaffold material to prevent postoperative infections. [ABSTRACT FROM AUTHOR]

Composite biomaterials can improve the mechanical and biological properties of ceramic scaffolds for bone tissue engineering application. In this study hydroxyapatite (HAp), and bioactive glass ceramics were synthesized by co-precipitation and ultrasound assisted sol-gel method. The synthesized HAp (80 wt.-%) and bioglass (15 wt.-%) bioceramics were further used with aluminum oxide (3 wt.-%) and starch (2 wt%) to prepare a composite biomaterial. The composite biomaterial was finally used to fabricate scaffold materials by employing nontoxic binder mediated gel-casting approach. The synthesized composite material and developed scaffolds were characterized through different physical, chemical, and morphological analyses, mechanical study, and in vitro biological assays. The synthesized scaffold exhibited 20–25% porosity, with a high compressive strength of ~ 157 ± 2 MPa, and Tensile strength of ~ 83 ± 2 MPa after sintering at 1200 °C for 2 h. The in vitro biological study confirmed the nontoxic behavior of the composite biomaterial and developed scaffolds with MG-63 osteoblast-like cell line. The developed composite scaffold facilitated new cell attachment, growth, and proliferation on its surface, all of which correlates with good osteoconductive properties. The developed scaffolds effectively simulated the morphology, porosity, mechanical property, and bioactivity of the bone structure for load-bearing tissue engineering application. [ABSTRACT FROM AUTHOR]