Shahid Chamran University of Ahvaz

This research aims to use neural-like cells (NLCs) derived from endometrial mesenchymal stem cells (EnMSCs) on a polylactic acid/chitosan scaffold (PLA/CS) along with the use of bacopa monnieri (Memocopa) in a rat sciatic nerve injury model for sciatic nerve regeneration. While previous studies have explored stem cell therapies and scaffold-based approaches for nerve regeneration, using EnMSCs in combination with a PLA/CS scaffold and Memocopa represents a novel, potentially synergistic approach.

EnMSCs were isolated, characterized, and differentiated in a study. The expression of specific genes in the differentiated cells was confirmed using RT-PCR and immunocytochemistry. PLA nanofiber and chitosan hydrogel scaffolds were created for neural tissue engineering. Memocopa was administered orally alongside scaffold and cell transplantation. The study involved 25 adult male Wistar rats with a 3 mm sciatic nerve gap, divided into five groups based on treatment. Animals were monitored for 8 weeks, during which SFI was measured. Tissue samples were then prepared for histological examination, including various staining techniques.

The combination of scaffold, cells, and Memocopa showed significant improvements in sciatic nerve function, as indicated by the SFI results in the eighth week: conduit group -33.87, conduit/cells group -25.92, conduit/cells/Memocopa group -22.86, Memocopa group -30.93, and control group -38.87. Histological findings revealed improvements in various aspects, including percentages of new nerve formation across the different treatment groups: conduit group 4.62 %, conduit/cells group 16.45 %, conduit/cells/Memocopa group 21.32 %, Memocopa group 7.07 %, and control group 0.22 %.

The results of this study showed that efficient differentiation of EnMSCs into NLCs is possible, and with the help of PLA/CS scaffold and simultaneous use of Memocopa, it is possible to repair and improve sciatic nerve injury in a rat animal model.

We applied DFT to explore the structural, electronic and magnetic characteristics, as well as optical properties of a new series of full Heusler Co₂HfZ (Z = Pb, Bi, As) CompoundsCalculations were conducted using the Quantum ESPRESSO software, employing various methods including the generalized gradient approximation (GGA-PBE), local spin d. approximations (LSDA), and GGA + U.Our research focused on the structural optimization of new compounds in different magnetic states for the Cu₂MnAl and Hg₂CuTi structures.Moreover, we performed calculations for various structural parameters, the band structure, and the total and partial spin moments of these alloys.Furthermore, we computed the different optical properties, in detail.Our calculations indicate that, the ferromagnetic phase in the Cu₂MnAl structure is the most stable configuration for these alloys.The calculations using GGA and GGA + U methods have confirmed that Co₂HfPb is a half-metallic alloy.Anal. of the band structure and d. of states has confirmed that Co₂ HfAs alloys and exhibit ferromagnetic properties in GGA, LSDA, and GGA + U calculationsAddnl., the cobalt atoms significantly affect the magnetic behavior of these alloys, as demonstrated by their at. magnetic moments.Furthermore, the dielec. function and reflectivity coefficient curves reveal metallic behavior at very low energy levels.

This study explores the application of weld overlays on A516 G-70 steel using different filler metals, including ER 2594 super duplex stainless steel, ER 2209 duplex stainless steel, and ER 316L austenitic stainless steel.The aim of the overlaying process was to enhance the corrosion resistance and erosion performance of the base alloy.Pulsed current gas tungsten arc welding was employed as the overlaying technique.Detailed microstructural assessments were performed using optical microscopy and field emission SEM, supplemented by energy dispersive X-ray spectroscopy.The ratio of ferrite to austenite was evaluated through X-ray diffraction anal. and measurements using a ferrite scope.Results indicated that increasing the heat input reduced the ferrite phase in the ER 2594 and ER 2209 overlays.To assess corrosion behavior, Tafel polarization and electrochem. impedance spectroscopy tests were carried out on both the substrate and the overlay materials.Among the overlays, ER 2594 produced under moderate heat input showed the best corrosion resistance, with a notably low corrosion current (i_corr = 6.6 nA/cm²) and higher impedance (Z) compared to other overlays.Furthermore, erosion performance was evaluated using a slurry test with water containing 5 wt% sand particles at a flow rate of 10 m/s, with an impact angle of 30°, and varying duration.The ER 2594 overlay proved substantially lower mass loss, indicating superior erosion resistance compared to both the base and other cladding alternatives.Based on the findings, the ER 2594 considered as the most suitable overlay filler for the A516 base material.