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Over the last ten years, magnesium (Mg)-based syntactic foams (SFs) have gained significant attention and their popularity continues to grow. This is because they possess unique properties such as high mechanical strength and are lightweight, making them potential candidates for applications in various industries, including aerospace, automotive, and biomedical (especially in orthopedics). This article reviews and discusses different fabrication techniques used in producing magnesium-matrix syntactic foams (Mg-MSFs). These techniques include stir casting, disintegrated melt deposition, powder metallurgy, and melt infiltration. The review comprehensively analyzes microstructure specifications, mechanical properties, and corrosion behavior exhibited by Mg-MSFs fabricated to date. The findings suggest that the properties of these foams, including microstructural characteristics, mechanical properties, and corrosion behavior, are significantly influenced by factors such as filler particle amounts and properties, Mg alloy-matrix specifications, fabrication techniques, process parameters, and post-processing treatments (such as annealing and sintering). These factors play a crucial role in determining the final characteristics of the syntactic foams. While Mg-MSFs hold substantial importance and potential, a limited body of research exists in this area. Therefore, more research is necessary to comprehensively understand these structures, which will facilitate their effective utilization in both industrial and biomedical applications.

The addition of nanoscale additions to magnesium (Mg) based alloys can boost mechanical characteristics without noticeably decreasing ductility. Since Mg is the lightest structural material, the Mg-based nanocomposites (NCs) with improved mechanical properties are appealing materials for lightweight structural applications. In contrast to conventional Mg-based composites, the incorporation of nano-sized reinforcing particles noticeably boosts the strength of Mg-based nanocomposites without significantly reducing the formability. The present article reviews Mg-based metal matrix nanocomposites (MMNCs) with metallic and ceramic additions, fabricated via both solid-based (sintering and powder metallurgy) and liquid-based (disintegrated melt deposition) technologies. It also reviews strengthening models and mechanisms that have been proposed to explain the improved mechanical characteristics of Mg-based alloys and nanocomposites. Further, synergistic strengthening mechanisms in Mg matrix nanocomposites and the dominant equations for quantitatively predicting mechanical properties are provided. Furthermore, this study offers an overview of the creep and fatigue behavior of Mg-based alloys and nanocomposites using both traditional (uniaxial) and depth-sensing indentation techniques. The potential applications of magnesium-based alloys and nanocomposites are also surveyed.

Introduction: Neurosurgery is considered a technically demanding specialty; nonetheless, it also requires non-technical skills (NTSs) to reach mastery. Research question: This study seeks to understand how important NTSs are perceived by neurosurgeons across diverse roles and socio-economic backgrounds. The objective is to identify key NTSs and explore their role in surgical precision, teamwork, and collaboration. Material and method: An international survey involving 372 neurosurgeons from various socio-economic and cultural contexts was conducted. The extensive sample and inclusive methodology provide a comprehensive perspective on the perceived importance of NTSs in neurosurgery. Results: The survey results highlight the universal significance of NTSs among neurosurgeons. Attention to detail, humility, and self-awareness are considered essential for surgical precision, effective teamwork, and collaboration. The findings underscore the necessity for integrated training programs that combine NTSs with technical skills. Discussion and conclusion: The study emphasizes the importance of effective training methods such as simulations, mentorship, and role-playing in equipping neurosurgeons to navigate the complexities of their profession. Future research should focus on optimizing teaching methods for NTSs, comparing traditional courses, online modules, and hybrid training programs. Addressing the global disparity in neurosurgical care, particularly in low- and middle-income countries, is crucial for improving patient outcomes worldwide.

Friction stir welding (FSW) currently contributes a significant joining process for welding aluminium, magnesium, and other metals in which no molten or liquid state were involved. It is well known that aluminium alloys are more effective, promising for different applications light weight, strength and low cost. This study aims to determine how such tools geometry and tool speed can be related to dissimilar material in the joining process. Specifically, it investigates whether the distribution of the weld zone particularly between tool pin profile to rotational speed. In this context, the influence of tool pin profile and tool rotational speed in relation to the mechanical properties and microstructure of friction stir welded. The aim of this study is also to test the hypothesis that better mixing between dissimilar metals at higher tool rotational speed along the weld path. Three different tool profiles were configured with AA5083 and AA7075. During welding, notable presence of various types of defects such as voids and wormholes in the weld region. The results of this work showed that the tool pin profile and weld parameter are significant in determining mechanical properties at different tool rotational speed. The highest tensile strength achieved was about 263 MPa and the defectfree joint was obtained by using the threaded tapered cylindrical pin tool at a rotational speed of 800 rpm. These findings indicate that different tool profiles influence differently on the formation of defects at welds. On this basis, the tool geometry should be considered when designing experimental friction stir welded joint.

Due to excessive use of antibiotics, resistance against microorganisms is developed. An alternative use of antibiotics, natural remedies from plants have been used against infectious diseases. In the current study, bioactive compounds from Calotropis procera (C. procera) root were extracted and chitosan and polyvinyl alcohol (CS-PVA) were used asa carriers and for the delivery to treat induced infection. Different concentration of C. procera extracts (25–75 mg/mL) were loaded on CS-PVA membrane and applied on the induced wounds in rabbits. Wound reduction was recorded for 12 days. On 6th day, small tissue from healing area were collected and subject to histopathology for tissue regeneration. The antioxidant activity (DPPH, TPC and TFC) was also investigated of CS-PVA loaded C. procera root extract. The DPPH free radical inhibition for 75 mg/mL were recorded up to 66.37%. The TPC and TFC contents were recorded to be 36.52 ± 5.12 GAE mg/g of DW (dry weight) and 24.49 ± 6.27 CE mg/g of DW (dry weight), respectively. The antibacterial activity was evaluated against Escherichia coli and Staphylococcus aureus in comparison to control (Rifampicin). The zones of inhibition were recorded to be 18.50 ± 2.30 and 20.40 ± 4.20, respectively for CS-PVA membrane loaded with 75 mg extracts along with Rifampicin 28.50 ± 2.5 and 30.50 ± 1.38. The CS-PVA membranes were also studied for swelling and biodegradability. The biodegradability was increased, while swelling was decreased of CS-PVA membranes loaded with extract. The bioactive compounds from the CS-PVA loaded with extract released in controlled and sustainable way. Result revealed that CS-PVA loaded C. procera root extract has promising antimicrobial and antioxidant activity and could possibly be employed for the treatment of infectious diseases.

Abstract Globally, the discipline of neurosurgery has evolved remarkably fast. Despite being one of the latest medical specialties, which appeared only around hundred years ago, it has witnessed innovations in the aspects of diagnostics methods, macro and micro surgical techniques, and treatment modalities. Unfortunately, this development is not evenly distributed between developed and developing countries. The same is the case with neurosurgical education and training, which developed from only traditional apprentice programs in the past to more structured, competence-based programs with various teaching methods being utilized, in recent times. A similar gap can be observed between developed and developing counties when it comes to neurosurgical education. Fortunately, most of the scholars working in this field do understand the coherent relationship between neurosurgical education and neurosurgical practice. In context to this understanding, a symposium was organized during the World Federation of Neurological Surgeons (WFNS) Special World Congress Beijing 2019. This symposium was the brain child of Prof. Yoko Kato—one of the eminent leaders in neurosurgery and an inspiration for female neurosurgeons. Invited speakers from different continents presented the stages of development of neurosurgical education in their respective countries. This paper summarizes the outcome of these presentations, with particular emphasis on and the challenges faced by developing countries in terms of neurosurgical education and strategies to cope with these challenges.

Despite the significant advancement in bone tissue engineering, it is still challenging to find a desired scaffold with suitable mechanical and biological properties, efficient bone formation in the defect area, and antibacterial resistivity. In this study, the zeolite (ZSM-5) scaffold was developed using the space holder method, and a novel vancomycin-loaded alginate coating was developed on it to promote their characteristics. Our results demonstrated the importance of alginate coating on the microstructure, mechanical, and cellular properties of the ZSM-5 scaffold. For instance, a three-fold increase in the compressive strength of coated scaffolds was observed compared to the uncoated ZSM-5. After the incorporation of vancomycin into the alginate coating, the scaffold revealed significant antibacterial activity against Staphylococcus aureus (S. aureus). The inhibition zone increased to 35 mm. Resets also demonstrated 74 ± 2.5% porosity, 4.3 ± 0.07 MPa strength in compressive conditions, acceptable cellular properties (72.3 ± 0.2 (%control) cell viability) after 7 days, good cell attachment, and calcium deposition. Overall, the results revealed that this scaffold could be a great candidate for bone tissue engineering.

This research study show performance comparison of the Net Asset Values (NAVs) return of Open-ended and Close-ended mutual funds in Pakistan. The aim of the study to analyze the dissimilarity between the “net asset values” (NAVs) returns of the open-ended and close-ended mutual funds. The monthly data of Net Asset Value return of both open-ended funds and close-ended funds were taken over the period from 2006 till 2011 (inclusive). The NAVs return was computed through (LN) natural log function. The normality test was conducted initially and then the Kolmogorov-Smirnov and Shapiro-Wilk test were applied, their result showed that the data is not normally distributed. The Mann- Whitney U test and then further the Kruskal Wallis was conducted to check for the differences between these two groups of independent variables. It showed dissimilarity between the net asset value returns of the open-ended and close-ended mutual funds. Further Kruskal Wallis test results indicated significant differences between the open-ended and close-ended funds. It is concluded that the performance of open-ended and close-ended mutual funds is not the same. Also, growth is witnessed in the mutual fund industry and many close-ended funds have been converted to open-ended funds.

This work deals with the investigation of different effects on the structural, magnetic, electronic and dielectric properties of Cd and Mn doped Bi0.75Cd0.25Fe1−xMnxO3 multiferroic samples by taking fixed ratios of Cd and varying the Mn ratio with values of x = 0.0, 0.5, 0.10 and 0.15. Cd-Mn doped samples were synthesized chemically using a microemulsion method. All the samples were finally sintered at 700 °C for 2 h to obtain the single phase perovskites structure of BiFeO3 materials. The synthesized samples were characterized by different techniques, such as X-ray diffractometry (XRD), Scanning Electron Microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), LCR meter and magnetic properties using VSM. XRD results confirm BFO is a perovskite structure having crystallite size in the range of 24–54 nm. XRD results also reveal observed structural distortion due to doping of Cd at the A-site and Mn at the B-site of BFO. SEM results depict that, as the substitution of Cd-Mn increases in BFO, grain size decreases up to 30 nm. FTIR spectra showed prominent absorption bands at 555 cm−1 and 445 cm−1 corresponding to the stretching vibrations of the metal ions complexes at site A and site B, respectively. Variation of dielectric constant (ɛ′) and loss tangent (tan δ) at room temperature in the range of 1 MHz to 3 GHz have been investigated. Results reveal that with Cd-Mn co doping a slight decrease in dielectric constant have been observed. Magnetic properties of Cd-Mn doped pure BFO samples have been studied at 300 K. Results reveal that undoped BiFeO3 exhibits weak ferromagnetic ordering due to the canting of its spin. Increase in magnetization and decrease in coercivity is a clear indication that a material can be used in high density recording media and memory devices. Keywords: Nanoparticles, Cd-Mn doped BiFeO3, FESEM, XANES, Magnetic properties

An amendment to this paper has been published and can be accessed via the original article.