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Nearly 80% of human chronic infections are caused due to bacterial biofilm formation. This is the most leading cause for failure of medical implants resulting in high morbidity and mortality. In addition, biofilms are also known to cause serious problems in food industry. Biofilm impart enhanced antibiotic resistance and become recalcitrant to host immune responses leading to persistent and recurrent infections. It makes the clinical treatment for biofilm infections very difficult. Reduced penetration of antibiotic molecules through EPS, mutation of the target site, accumulation of antibiotic degrading enzymes, enhanced expression of efflux pump genes are the probable causes for antibiotics resistance. Accordingly, strategies like administration of topical antibiotics and combined therapy of antibiotics with antimicrobial peptides are considered for alternate options to overcome the antibiotics resistance. A number of other remediation strategies for both biofilm inhibition and dispersion of established biofilm have been developed. The metallic nanoparticles (NPs) and their oxides have recently gained a tremendous thrust as antibiofilm therapy for their unique features. This present comprehensive review gives the understanding of antibiotic resistance mechanisms of biofilm and provides an overview of various currently available biofilm remediation strategies, focusing primarily on the applications of metallic NPs and their oxides.

In today's complex Micro-Electro-Mechanical Systems (MEMS), investigation of flow through irregular micro/nanochannels, such as bended channels, variable cross-sectional area channels, and those with rough surfaces, can contribute considerably to efficient designing of the microdevices and to gain a better understanding of the flow structure in these geometries. The present paper reviews the prominent studies published in literature on rarefied gas flow through these types of complex geometries. The main focus of the study is to explore the physical aspects of the findings and the analyses provided in support of the results. Finally, the areas in which a gap exists in literature and could be subjects of future studies are introduced.

Nearly 80% of human chronic infections are caused due to bacterial biofilm formation. The increased resistance against the conventional antimicrobial agents makes it difficult to treat the biofilm-related infections. The antibiotics resistance developed by planktonic cells has also become a major threat for human. Therefore, we have attempted here to develop an effective alternative strategy to overcome the issues of antibiotics resistance of bacteria. Upon synthesis, biogenic C-dots were combined with lysozymes which were further encapsulated into chitosan nanocarrier to form C-dots carrier (CDC). The as-synthesized C-dots were found irregular shaped and the average size of C-dots and CDC were 8 ± 2 nm and 450 ± 50 nm, respectively. To ensure secure and targeted delivery of C-dots and lysozyme we have employed chitosan, a biodegradable and natural biopolymer, as a delivery system. The study of time-dependent bacterial growth and flow cytometry analysis demonstrated that CDC can exhibit a synergistic bactericidal activity against the antibiotics resistant recombinant E. coli cells. Further, we have shown that the CDC could be a potent agent for both prevention of biofilm formation and eradication of preformed biofilm. In addition, we have observed that our drug delivery system is hemocompatible in nature making it suitable for in vivo applications. Therefore, we believe that the combination therapy of C-dots and lysozyme may be used as an excellent antibacterial and antibiofilm strategy.

The influence of rarefaction effects on technical processes is studied numerically for a heat transfer problem in a rarefied gas, a box with bottom heated plate. Solutions obtained from several macroscopic models, in particular the classical Navier-Stokes-Fourier equations with jump and slip boundary conditions, and the regularized 13 moment (R13) equations [Struchtrup & Torrilhon, Phys. Fluids 15, 2003] are compared. The R13 results show significant flow patterns which are not present in the classical hydrodynamic description.