卡尚大学

Liver fibrosis is the second stage of liver disease with few specific treatments currently available. Probiotics, specifically bifidobacterium longum can be used to alleviate liver fibrosis through several mechanisms such as reducing oxidative stress and inflammation, leading to restoring liver function and enhancing its histological parameters. However, probiotics viability can be reduced during gastrointestinal transit, diminishing treatment efficiency. Therefore, encapsulating them in matrices of carbohydrates (e.g., alginate and chitosan), and proteins (e.g., whey protein) may increase their viability and might positively affect their treatment efficacy. As a result, we hypothesized that encapsulation in alginate-whey protein matrix with a chitosan coat would enhance the delivery and hepatoprotective effects. Therefore, in this research we assessed the effect of bifidobacterium longum encapsulated with alginate-whey protein with chitosan coating on liver function tests, oxidative stress parameters, inflammatory gene expression and histological parameters in liver tissue. 48 male Male Wistar rats were categorized into 6 control and treatment groups: Normal control (NC), sham-operated control (SHC), BDL control (BDL + vehicle), free B.longum probiotic (BDL + FP), free microcapsule (BDL + FC), and encapsulated B. longum probiotic (BDL + CP). Free and encapsulated B. longum was administered at a dose of 3× 10^9 Colony forming units (CFU) per day for 7 days before and 21 days following induction of cholestasis by bile duct ligation (BDL) surgery. After the treatment, all rats were euthanized, and their blood samples and liver tissue were collected for analysis. Liver function tests were assessed in blood plasma, while liver tissue was used for oxidant/anti-oxidant status measurement, pro- and anti-inflammatory gene expression, and histological properties. Our results showed that encapsulation of B. longum with alginate-whey protein and chitosan coating can provide a microcapsule with encapsulation efficiency of 76.6

This work analyzes the deflection and buckling behavior of a sandwich curve beam with variable cross-section using the fifth-order shear deformation theory (FISDT) with finite element method (FEM). The beam comprises nanocomposite face sheets reinforced with carbon nanotubes (CNTs) and graphene platelets (GPLs), piezoelectric layers. Also, various porous patterns (three types) or two type honeycomb core (hierarchical and conventional) for a sandwich curve beam are investigated. The governing equations are derived from FISDT and converted into their weak form based on FEM application. The stiffness and buckling matrices are subsequently formulated to assess the beam's deflection and critical buckling load. The normal and shear stresses for a sandwich curve beam along the thickness are obtained and plotted. A 1% augmentation in CNT content reduces the transverse deflection by 42.2% and increases the buckling load by 42.4%. A symmetric porosity distribution results in greater stiffness in comparison of other cases, also, a negative applied voltage enhances the critical buckling load. Increasing the honeycomb angle and aspect ratio enhances transverse displacement. The variation coefficient of the cross-section (alpha) positively affects buckling resistance, thus, the critical buckling load increases, and vice versa for deflection. Also, the parabolic cross section yielding the lowest critical buckling load. Conversely, augmenting the radius of curvature (R) diminishes the critical buckling load. In honeycomb cores, an increase in the internal hexagonal angle and the ratio of the hexagon's diameters leads to reduce the stiffness and stability, thus the critical buckling load decreases, while it is vice versa for deflection of a sandwich curve beam. Clamped-clamped supports produce the minimum deflection and the maximum buckling load among boundary conditions. The present work demonstrates that the fifth-order shear deformation theory markedly enhances the precision of buckling predictions for a sandwich curve beam. The suggested model offers significant insights into the design of lightweight, high-stiffness, and multifunctional smart structures for the aerospace, automotive, and marine sectors.

This research conducts a nonlinear analysis of free vibrations in a cylindrical panel comprising auxetic metal metamaterials enhanced with graphene origami (GOri), subjected to thermal loading and supported by an elastic foundation. The integration of GOri particles is observed to markedly improve the panel's mechanical characteristics, which are quantified through a micromechanical modeling approach. The investigation incorporates five distinct through-thickness schemes for distributing GOri particles within the structure. Governing equations for the panel are formulated using first-order shear deformation theory alongside Hamilton's principle, while von Karman's nonlinear kinematic assumptions are implemented to capture geometric nonlinearities. Once the nonlinear partial differential equations are established and simply supported boundary conditions applied, Galerkin's procedure is utilized to condense the system into a single nonlinear equation describing transverse displacement. Perturbation analysis and the modified Poincar & eacute;-Lindstedt technique are then adopted to determine the structure's nonlinear natural frequencies. A notable feature of nonlinear free vibrations, as opposed to the linear case, is the dependence of natural frequencies on initial system conditions. The roles of various factors such as the dimensionless magnitude of initial disturbance, temperature variations, GOri concentration and distribution styles, fold parameters, structural geometry and foundation stiffness are systematically explored. To ensure robustness and reliability, the analytical framework, solution process and computed results are cross-validated through comparative analysis. Findings indicate that the initial state significantly influences vibrational characteristics, and higher temperatures lead to a pronounced reduction in nonlinear frequency.

In recent years, with the advancement of nanotechnology, another type of nanofluid (NF) called hybrid nanofluid (HNF) has been welcomed by researchers. This research discusses the production and measurement of viscosity ( _HNF ) and thermal conductivity ( k_HNF ) of HNF in the laboratory simultaneously. HNF of H2O–EG/MWCNT–ZnO–Cu is made using two-step method. Also, the effects of temperature (T) and volume fraction (ɸ) on _HNF and k_HNF are investigated. The output results are presented for T = 25–50 °C and ɸ= 1.4–3.0 k_HNF and decrease in _HNF . This is while increasing ɸ increases _HNF parameters and k_HNF . With increasing T, the average intermolecular forces decrease. Finally, it can be concluded that adding ZnO, MWCNT and Cu–H2O and EG-based fluids effectively improves thermal performance (TP).

A Ni(II) complex was obtained from the reaction of nickel chloride and 4,4′-trimethylenedipiperidinium chloride (H2TMDPCl2). Moreover, this thermochromic complex was embedded in silica hybrid material and characterized, as well. The present study is dealing with comparing the thermochromic behavior of this compound including phase transition temperature in these two situations. The thermochromic compound was synthesized by mechanochemical method, while, the composite was prepared by sol-gel method at room temperature. They both exhibit a yellow-to-blue color transition under heating. The samples have been subjected to multiple heating/cooling cycles and the dark blue color at elevated temperature fully reverses to the original green-yellow color upon cooling. In order to study the structure and the thermochromic behavior of the complex, Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), thermal analysis (TG/DTG/DSC), element analysis, X-ray diffraction (XRD) analysis were performed.