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Growing antibiotic resistance has been reported as a great health problem throughout the world. The threat of multidrug resistance is significantly exacerbated in biofilmassociated infection as most of the antimicrobials are rarely effective against biofilm and its virulence factors. Consequently, there is a strong demand for developing novel approaches and new materials to treat biofilm-associated bacterial infection. Engineering technology introduces nanoparticle-mediated drug delivery to reduce treatment failure and increase the synergistic effects of the drugs. Cationic antimicrobial peptides (CAMPs) are usually attracted to negatively charged bacterial phospholipid membrane and kill the microbial pathogens by disintegrating their cell membrane with the subsequent collapse of infective pathogenesis. Previous studies have already provided evidence of the success of AMPs to treat the biofilm-associated multidrug-resistant bacterial infection. Although, there are some challenges to use AMPs in clinical practice such as proteolytic degradation, cytotoxicity, instability, low membrane permeability which diminishes the effects of AMPs as a wide spectral antibacterial agent. To enhance the highest therapeutic capacity of AMPs, research should need to be performed on designing a combination strategy to triumph over the difficulties of AMPs in the clinical application. The purpose of this review is to investigate the synergistic relationship of AMPs with a different type of antimicrobial agent including a nanocarrier drug delivery system to accomplish the clinical practice against drug-resistant bacterial infection.

Carburization of cladding materials has long been a concern for the nuclear industry and has led to the restricted use of high-thermal conductivity fuels such as uranium carbides. With the rise of small modular reactors (SMRs) that frequently implement a graphite core-block, carburization of reactor components is once more in the foreground as a potential failure mechanism. To ensure commercial viability for SMRs, neutron-friendly cladding materials such as Zr-based alloys are required. In this work, the carburization kinetics of Zircaloy-4 (Zry-4), for the temperature range 1073–1673 K (covering typical operating temperatures and off-normal scenarios) are established. The following Arrhenius relationship for the parabolic constant describing ZrC growth is derived: Kp (in μm2/s) = 609.35 exp(−1.505 × 105/RT)). Overall, the ZrC growth is sluggish below 1473 K which is within the operational temperature range of SMRs. In all cases the ZrC that forms from solid state reaction is hypo-stoichiometric, as confirmed through XRD. The hardness and elastic modulus of carburized Zry-4 are also examined and it is shown that despite the formation of a ZrC layer, C ingress in the Zry-4 bulk does not impact the mechanical response after carburization at 1073 K and 1473 K for 96 h.

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