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This paper envisions Ti40Zr10Cu36Pd14 bulk metallic glass as an oral implant material and evaluates its antibacterial performance in the inhabitation of oral biofilm formation in comparison with the gold standard Ti-6Al-4V implant material. Metallic glasses are superior in terms of biocorrosion and have a reduced stress shielding effect compared with their crystalline counterparts. Dynamic mechanical and thermal expansion analyses on Ti40Zr10Cu36Pd14 show that these materials can be thermomechanically shaped into implants. Static water contact angle measurement on samples surface shows an increased surface wettability on the Ti-6Al-4V surface after 48 ​h incubation in the water while the contact angle remains constant for Ti40Zr10Cu36Pd14. Further, high-resolution transmission and scanning transmission electron microscopy analysis have revealed that Ti40Zr10Cu36Pd14 interior is fully amorphous, while a 15 ​nm surface oxide is formed on its surface and assigned as copper oxide. Unlike titanium oxide formed on Ti-6Al-4V, copper oxide is hydrophobic, and its formation reduces surface wettability. Further surface analysis by X-ray photoelectron spectroscopy confirmed the presence of copper oxide on the surface. Metallic glasses cytocompatibility was first demonstrated towards human gingival fibroblasts, and then the antibacterial properties were verified towards the oral pathogen Aggregatibacter actinomycetemcomitans responsible for oral biofilm formation. After 24 ​h of direct infection, metallic glasses reported a >70% reduction of bacteria viability and the number of viable colonies was reduced by ∼8 times, as shown by the colony-forming unit count. Field emission scanning electron microscopy and fluorescent images confirmed the lower surface colonization of metallic glasses in comparison with controls. Finally, oral biofilm obtained from healthy volunteers was cultivated onto specimens surface, and proteomics was applied to study the surface property impact on species composition within the oral plaque.

Thin and flexible materials that can provide efficient electromagnetic interference (EMI) shielding are urgently needed, particularly those that can be rapidly processed and withstand harsh environments. Cobalt‐based metallic glasses stand out as prime candidates due to their excellent soft magnetic properties, satisfactory shielding features, and mechanical properties. Herein, a recently developed technique is used to fabricate metallic glass microfibers from Co66Fe4Mo2Si16B12 alloy. The produced microfibers are characterized for their size and uniformity by scanning electron microscopy and their amorphous structure is confirmed by X‐ray diffraction (XRD) and differential scanning calorimetry (DSC). The cobalt‐based metallic glass microfibers show an EMI shielding factor that reaches five in the static regime and obtains an up to 25‐fold increase of the attenuation constant in the Ku frequency band. This performance originates from the combination of soft magnetic properties and excellent electrical conductivity. In addition, the flexible microfibers exhibit excellent hardness and elasticity making them suitable for EMI shielding of complex geometries. Their hardness and elastic modulus are measured by nanoindentation to be 11.31 ± 0.60 GPa, and 110.54 ± 11.24 GPa, respectively. [ABSTRACT FROM AUTHOR]

Tissue engineering provides novel methods for a wide variety of skin injuries, among which, the electrospun nanofibers have attracted special attention for wound dressing fabrications. In this research, we have fabricated scaffolds based on Poly l-lactic acid (PLLA) and Polyethylene oxide (PEO) polymers and have loaded the hybrid PLLA/PEO with active substances, Argireline and Dexpanthenol. The five categories of nanofiber scaffolds were prepared by electrospinning: (1) PLLA, (2) PLLA/PEO hybrid scaffold, (3) PLLA/PEO hybrid scaffold loaded with Argireline (PLLA/PEO/A), (4) PLLA/PEO hybrid scaffold loaded with Dexpanthenol (PLLA/PEO/D), (5) PLLA/PEO hybrid scaffold loaded with Argireline and Dexpanthenol (PLLA/PEO/A/D). Our SEM analysis of the electrospun nanofibers shows that all nanofibers are bead-free and are in the range of 200–600 nm. The static water contact angle measurements via the sessile drop method have shown a transition from a hydrophobic surface for the PLLA scaffold (CA = 118.43 ± 1.6°) to a hydrophilic surface for PLLA/PEO hybrid scaffold (CA = 35.5 ± 2.8°). The addition of Argireline, Dexpanthenol, and a mixture of both has been shown to improve this wettability even further. The electrospun nanofiber scaffolds were further analyzed for their air permeability, and mechanical properties. The cytocompatibility analysis indicated superior performance for PLLA/PEO loaded with both Argireline and Dexpanthenol. The in-vivo analysis was conducted on the second-degree burn rat models in six different studied groups: 1-healthy rat, 2-negative control, and rats treated with 3-PLLA/PEO, 4-PLLA/PEO/A, 5-PLLA/PEO/D, and 6-PLLA/PEO/A/D. The wound area reduction was assessed on day 3, day 7, and day 14 in all groups along with the histology analysis based on hematoxylin/eosin. Our results show that rats treated with PLLA/PEO/A/D not only have a great reduction in the wound area, but their histology analysis demonstrates high angiogenesis and collagen formation, and epithelialization. We believe the existence of both active substances has a synergic effect on the wound healing process. [ABSTRACT FROM AUTHOR]

Fe40Ni40B20 metallic glass is a key material among the many amorphous systems investigated thus far, owing to its high strength and appealing soft magnetic properties that make it suitable for use as transformer cores. In this study, Fe40Ni40B20 microfibers are fabricated down to 5 µm diameter. Three different melt–spinning wheel velocities: ≈51 m s−1, ≈59 m s−1, and ≈63 m s−1 (MG1, MG2, MG3) are used. Their fully amorphous structure is confirmed using X–ray diffraction, and differential scanning calorimetry (DSC) traces reveal a larger relaxation profile for the higher–quenched microfiber. Vibrating sample magnetometer measurements showed a higher saturation magnetization of 136 emug−1 for annealed metallic glass microfibers with a wheel velocity of 59.66 ms−1. Cylindrical magnetic field shields are obtained by aligning and wrapping the fibers around a cast. The observed anisotropic static field shielding behavior is in accordance with the microfibers' anisotropic nature. Composite samples are also produced by embedding the microfibers in an epoxy matrix to investigate their electromagnetic properties at GHz frequencies. Inclusion of the microfibers increase the composite's attenuation constant by 20 to 25 times, making it an ideal candidate for applications in the communications frequency range. [ABSTRACT FROM AUTHOR]

This work aims to evaluate the potential suitability of nonvitrified and vitrified bottom ashes to serve as substitute materials for both OPC and sand in mortars on an industrial scale. Three bottom ashes were selected as OPC substitutes: one was vitrified inside the incinerator plant (W1‐C), one was carbonated under ambient conditions for 3 months (W2‐C), and part of the carbonated bottom ash was further washed with Ca(OH)2 (W2‐W‐C). Composition and phases of the bottom ash sources were assessed by XRF and XRD, respectively. Thereafter, mortars were prepared by replacing 10, 20 or 30 wt% of OPC with these bottom ashes. It was shown that even though Ca(OH)2 washing step (W2‐W‐C) led to an increment of the compressive strength in final mortars compared to the use of W2‐C, it failed to reach the mechanical performance of OPC. On the contrary, the use of vitrified bottom ashes (W1‐C) could lead to obtaining compressive strength comparable to that of standard mortar if added up to 10 wt%. Regarding the sand substitution, vitrified bottom ashes could reach suitable compressive strength when replacing 20 wt% of standard sand. The alkali aggregate reaction test confirmed the neutrality of substitution material added up to 50 wt%. [ABSTRACT FROM AUTHOR]

Rice husk, an agricultural waste, is abundantly available in many countries such as China, India, Brazil, US, and South East Asia. Despite the massive production of rice husk, it is mainly disposed to landfill. In this work, utilization of rice husk for a potential waste‐water treatment is evaluated, along with subsequent encapsulation of the adsorbed heavy metals (Pb and Cd) inside a porous glass‐ceramic. Vitrified bottom ash (another source of waste) was mixed with foaming agents in dif‐ ferent weight ratios (40:60, 50:50, and 60:40) to prepare a glass matrix for encapsulation of Pb‐/Cd‐loaded rice husk. It was shown that using 40 wt% vitrified bottom ash with 60 wt% foaming agents leads to a foam glass with the best pore size distribution. Therefore, this batch was further mixed with 70 volume% (5 wt%) heavy metal‐loaded rice husk and was heat‐treated at 750°C for 3 hours. The final glass‐ceramic porous structure was char acterized using SEM, XRD, compression test, and it was shown that it is safe to be used as it passes the EN12457‐2 leaching test. [ABSTRACT FROM AUTHOR]

This paper envisions Ti 40 Zr 10 Cu 36 Pd 14 bulk metallic glass as an oral implant material and evaluates its antibacterial performance in the inhabitation of oral biofilm formation in comparison with the gold standard Ti-6Al-4V implant material. Metallic glasses are superior in terms of biocorrosion and have a reduced stress shielding effect compared with their crystalline counterparts. Dynamic mechanical and thermal expansion analyses on Ti 40 Zr 10 Cu 36 Pd 14 show that these materials can be thermomechanically shaped into implants. Static water contact angle measurement on samples' surface shows an increased surface wettability on the Ti-6Al-4V surface after 48 ​h incubation in the water while the contact angle remains constant for Ti 40 Zr 10 Cu 36 Pd 14 . Further, high-resolution transmission and scanning transmission electron microscopy analysis have revealed that Ti 40 Zr 10 Cu 36 Pd 14 interior is fully amorphous, while a 15 ​nm surface oxide is formed on its surface and assigned as copper oxide. Unlike titanium oxide formed on Ti-6Al-4V, copper oxide is hydrophobic, and its formation reduces surface wettability. Further surface analysis by X-ray photoelectron spectroscopy confirmed the presence of copper oxide on the surface. Metallic glasses cytocompatibility was first demonstrated towards human gingival fibroblasts, and then the antibacterial properties were verified towards the oral pathogen Aggregatibacter actinomycetemcomitans responsible for oral biofilm formation. After 24 ​h of direct infection, metallic glasses reported a >70% reduction of bacteria viability and the number of viable colonies was reduced by ∼8 times, as shown by the colony-forming unit count. Field emission scanning electron microscopy and fluorescent images confirmed the lower surface colonization of metallic glasses in comparison with controls. Finally, oral biofilm obtained from healthy volunteers was cultivated onto specimens' surface, and proteomics was applied to study the surface property impact on species composition within the oral plaque., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Authors.)