In this study, the cellular viability and function of immortalized human cervical and dermal cells are monitored and compared in conventional 2D and two commercial 3D membranes, Collagen and Geltrex, of varying working concentration and volume. Viability was monitored with the aid of the Alamar Blue assay, cellular morphology was monitored with confocal microscopy, and cell cycle studies and cell death mechanism studies were performed with flow cytometry. The viability studies showed apparent differences between the 2D and 3D culture systems, the differences attributed in part to the physical transition from 2D to 3D environment causing alterations to effective resazurin concentration, uptake and conversion rates, which was dependent on exposure time, but also due to the effect of the membrane itself on cellular function. These effects were verified by flow cytometry, in which no significant differences in viable cell numbers between 2D and 3D systems were observed after 24 h culture. The results showed the observed effect was different after shorter exposure periods, was also dependent on working concentration of the 3D system and could be mediated by altering the culture vessel size. Cell cycle analysis revealed cellular function could be altered by growth on the 3D substrates and the alterations were noted to be dependent on 3D membrane concentration. The use of 3D culture matrices has been widely interpreted to result in “improved viability levels” or “reduced” toxicity or cellular “resistance” compared to cells cultured on traditional 2D systems. The results of this study show that cellular health and viability levels are not altered by culture in 3D environments, but their normal cycle can be altered as indicated in the cell cycle studies performed and such variations must be accounted for in studies employing 3D membranes for in vitro cellular screening.

Bacterial infections are one of the most dangerous infections that threaten the existence and continuity of life.

Despite the discovery and manufacturing of effective antibiotics to tackle these menaces, bacteria have developed

resistance against such treatments and transformed into new mutant resistant strains. Bacteriophages, or phages, are

regarded as effective alternative antibacterial agents. Recently, scientists have been taking a closer look at the variety of

different phages that attack bacteria. This review primarily focuses on the potential of phage therapy as an alternative

treatment to overcome a wide spectrum of resistant bacterial infections, as well as current phage therapy advancement. It

also proposes the idea of engineering “broad-spectrum phage” to overcome a wide range of resistant bacterial infections,

and its advantages over antibiotics, individual phage, and phage cocktails.

Mathematical modelling of real-life problems usually results in functional equations, like ordinary or partial differential equations, integral and integro- differential equations, stochastic equations. Many mathematical formulation of physical phenomena contain integro-differential equations, these equations arises in many fields like fluid dynamics, biological models and chemical kinetics integro-differential equations are usually difficult to solve analytically so it is required to obtain an efficient approximate solution.

In this paper we establish the existence of solution for two boundary value problems of Fredholm functional integro-differential equations with nonlocal boundary conditions.

The effect of the rare earth (RE) element Y on the microstructure and hardness of (Mg–0.5Zn–0.5Zr–2.8Nd –1.5Gd) wt% Mg alloy investigated. 1 wt. % Y was added and compared with the base alloy. The microstructure results show the refinement of the grain by the addition of Y and the grains became smaller about 31.8 % and the volume fraction was increases 11.1% %, which led to the increment of hardness from 48.33 HV (as-cast EV31A) to 53.71 HV (as-cast EV31A +1 Y). Energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) results showed that the base alloy mainly contained α-Mg matrix and Mg-(Nd, Gd) as a second phase crystallized along the grain boundaries and addition of (Y) yttrium resulted in the formation of the new phase, Mg-Zn-Y-phase was found as a new ternary phase, where Y combined with the original second phase.

The influence of holmium on the microstructure and hardness of Mg-Nd-Gd-Zn-Zr alloys 

were investigated. Conventional casting methods are used to produce the alloys. All the results were 

characterized by optical microscopy, scanning electron microscope (SEM) and the Vickers hardness 

test to highlight the influence of holmium addition. The addition of 2.0 wt.% holmium leads to the 

combination of rare earth elements which formed Mg-Zn-Nd-Ho phase. The results have shown the 

addition of Ho improved the microstructure and hardness of Mg-Nd-Gd-Zn-Zr alloys. By adding 

grain size of 2.0 wt.% holmium had reduced by 18.43%, while the volume fraction increased by 

7.34%. The Vickers hardness value improved 6.18% due to the grain refine and volume fraction 

precipitates. The 2.0 wt.% holmium addition showed a positive result in microstructure and 

hardness value.