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This paper presents a mathematical modelling of a novel multiphysics (electro-mechanic coupling) problem of the shear wave propagation in laminated structures (piezoelectric - hydrogel - elastic substrate) using the wave mode method while finding the general solution for each medium. A dynamic mechanical equilibrium equation (for transverse deflection) and Maxwell equation (for electric potential) are solved in a coupled manner over each domain resulting a general closed-form solution. A specific analytical solution is then obtained enforcing the boundary conditions at the top of piezoelectric layer and the interface continuity requirements between each layer and the elastic half-space. A novel approach, to uncouple the coupled equations, is presented resulting in a final systematic solution. The effect of x coordinate (thickness) on the field variables is carefully examined for the electrically open and short cases. The jump in the stress and electric displacement components (causing delamination due to shearing mode of fracture) is present across all the interfaces due to the different bulk material constants. The key contribution of the current work is demonstrating the influence of fixed-charge concentration inside the hydrogel layer on the shear wave propagation. The present study thus provides a new concept for adjusting and controlling the elastic wave propagation in the composite structures, and provides a proper theoretical understanding of wave propagation in the damage tolerance-based design of piezotronics devices.

The gap between demand and supply for the required bone graft and donor is widening day by day. Tissue engineering approach is used to overcome the limitations of bone graft substitutes. In Tissue Engineering, a biocompatible scaffold is placed inside the body, which over a period of time gets converted into the bone Extra-Cellular Matrix (ECM). Hydroxyapatite (HA) and β-Tricalcium Phosphate (β-TCP) are extensively studied to fabricate bone scaffolds for tissue engineering applications by conventional methods. However, the scaffold needs to be produced with controlled pore size, porosity, and pore interconnectivity for homing of the cells which can be achieved by additive manufacturing. Also, the scaffolds produced with conventional methods lack mechanical properties which limit the use of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) at the recipient site. In this paper, scaffolds with different materials' compositions, different layers orientations, and pore sizes are designed as an input parameter for different scaffold architecture which has not been previously studied considering extrusion-based additive manufacturing. These parameters are considered to predict the mechanical properties of the scaffold architecture. It has been found that in all combinations the scaffold with 0°- 90°- 0°- 90° orientation layer gives Young’s modulus that is comparable to natural human bone. However, the scaffolds with 0°- 90° -0°- 90° orientation layer and 350 µm pore size gives comparatively higher effective Young’s modulus of about 30.948 GPa for 5% HA composition. In the future 0°- 90°- 0°- 90° orientation can be considered to fabricate 3D scaffold architecture using extrusion-based additive manufacturing method.

Kidney fibrosis is marked by excessive extracellular matrix deposition during disease progression. Unfortunately, existing kidney function parameters do not predict the extent of kidney fibrosis. Moreover, the traditional histology methods for the assessment of kidney fibrosis require liquid and imaging biomarkers as well as needle-based biopsies, which are invasive and often associated with kidney injury. The repetitive analyses required to monitor the disease progression are therefore difficult. Hence, there is an unmet medical need for non-invasive and informative diagnostic approaches to monitor kidney fibrosis during the progression of chronic kidney disease. Here, we summarize the modern advances in diagnostic imaging techniques that have shown promise for non-invasive estimation of kidney fibrosis in pre-clinical and clinical studies.

We show that any two planar cubic embeddings of a pseudoplanar curve of genus 1 (over complex numbers) are linearly equivalent. We describe the ‘abstract moduli’ of nonsingular affine plane cubic curves with 3 places at infinity. We note some examples of inequivalent planar embeddings of a nonsingular affine curve of genus 0 having 2 places at infinity.

In this paper, an analytical approach to predict the bend angle of sheet formed with multiple laser scans is proposed. The proposed approach considers the temperature dependent properties of the sheet material to evaluate the temperature profile across the thickness of sheet Based on this temperature profile, the strain energy stored in the laser irradiated area is estimated and the same is utilized to determine the final bend angle. To validate the feasibility of the proposed model, experiments were performed on AISI 304 steel sheet with different processing conditions and the predicted bend angle is compared with the experimental result. Finally, the effect of process parameters on the laser formed sheet is discussed.

Fibrosis is a wound-healing process that results in tissue scarring and organ dysfunction. Several novel mechanisms of fibrogenesis have been discovered recently. In this review, we focus on the role of poly-ADP ribose polymerase (PARP) in major organ fibrosis, such as lungs, heart, liver, and kidneys. PARP is a dynamic enzyme that modulates different cellular proteins by the addition of PAR groups and mediates an array of cellular events in both normal physiological and pathophysiological states. The US Food and Drug Administration (FDA) and European Medicines Agency (EMA) recently approved several PARP inhibitors, such as olaparib, niraparib, talazoparib, and rucaparib, for the treatment of ovarian and germline BRCA-mutant breast cancers. Consequently, repurposing these drugs could provide an opportunity to counter organ fibrosis.

Centrifugal filtration is a mechanical method of separation which uses centrifugal force and density difference for separation of particles. The paper aims to optimize the filter design in order to maximize the filtration efficiency and increase the reusability of the fluid by varying the input parameters. This is achieved by analyzing the particle behavior using Discrete Phase Modelling and Taguchi approach. The filtration efficiency is found to be significantly enhanced by changes in design and process parameters in the system. Increased efficiency could assure higher quality of fluid, which enhances its reusability.