This study explored the impact of online lectures that were developed using principles of cognitive load theory (CLT) and cognitive theory of multimedia learning (CTML) on health profession students' lecture comprehension, cognitive load, cognitive engagement, and intrinsic motivation in learning. A total of 215 first-year undergraduate students in medical, dentistry, and nutrition programs participated in this pre-post quasi experimental study. The students attended a typical face-to-face lecture on Day-1 of the intervention, followed by a CLT-based online lecture 8 weeks thereafter. Their comprehension of the lecture topics was measured through pre- and post-lecture assessments, and their cognitive load, cognitive engagement, and motivation were measured immediately after each lecture session. The analysis revealed that the CLT-based online lectures promoted the students' comprehension of the lecture content (p < 0.001), self-perceived learning (p < 0.001), engagement toward the learning material, and motivation to learn (p = 0.025). It was also effective at reducing the students' intrinsic and extraneous cognitive loads (p < 0.001). Hence, designing online lectures using CLT and CTML principles could be an effective method to promote students' knowledge and comprehension, cognitive engagement, and learning motivation. However, further research is needed to investigate the applicability and impact of CLT-based online lectures in non-health profession disciplines.

The astonishing outbreak of SARS-CoV-2 coronavirus, known as COVID-19, has attracted numerous research interests, particularly regarding fabricating antimicrobial surface coatings. This initiative is aimed at overcoming and minimizing viral and bacterial transmission to the human. When contaminated droplets from an infected individual land onto common surfaces, SARS-CoV-2 coronavirus is able to survive on various surfaces for up to 9 days. Thus, the possibility of virus transmission increases after touching or being in contact with contaminated surfaces. Herein, we aim to provide overviews of various types of antiviral and antimicrobial coating agents, such as antimicrobial polymer-based coating, metal-based coating, functional nanomaterial, and nanocomposite-based coating. The action mode for each type of antimicrobial agent against pathogens is elaborated. In addition, surface properties of the designed antiviral and antimicrobial polymer coating with their influencing factors are discussed in this review. This paper also exhibits several techniques on surface modification to improve surface properties. Various developed research on the development of antiviral/antimicrobial polymer coating to curb the COVID-19 pandemic are also presented in this review.

The objective of this study is to characterize the effect of in situ heat treatment on polylactic acid (PLA) and plasticized PLA during fused deposition modelling (FDM) with the motivation to improve their mechanical, thermal and physical properties. The in situ heat treatment was formed during the FDM by adjusting the bed temperature to 70°C, 90°C and 120°C. The performance of 3D, the printed samples, was compared with the compression moulded samples treated at the same temperature using a vacuum oven. PLA was plasticized with poly (ethylene glycol) (PEG) at different compositions of 0, 5 and 10 wt% of PEG. The properties of PLA, plasticized PLA and FDM-printed sample were analysed using Instron, differential scanning calorimeter (DSC) and X-ray diffraction (XRD). It was found that the addition of PEG into PLA decreased the tensile strength, elongation at break and tensile modulus of the materials. However, after heat treatment in the vacuum oven and FDM, the properties were generally higher at 90°C and this was believed to be primarily due to the effect of crystallization. This can be proved by formation of double melting peak, correspond to melt-crystallization mechanism, observed in DSC. The formation of different crystal was supported by XRD analysis where the amorphous peak had transformed into sharp peak at 16.9° and 19.3°, which indicates an improved crystallinity. Comparison between the compression moulded sample and FDM demonstrated that the in situ heat treatment in FDM had the most significant impact on tensile modulus.

In response to the increasing amount of global plastic waste, biodegradable polymers have been brought into the spotlight. Recently, extraordinary progress has been made in the development of smart biodegradable polymers by researchers around the globe. Shape memory polymers, self-healing polymers, piezoelectric polymers, chromogenic polymers and magneto rheological elastomers are the known classifications of smart biodegradable polymers. Among all, piezoelectric polymers have the highest demand in the market. This review provides a brief look at the examples of smart biodegradable polymer, methods of modification, derived properties and suitable applications. Polylactic acid (PLA) was found to be the most common polymer matrix employed in creating smart biodegradable polymers. Used modification techniques include copolymerization, blending and composite forming. Shape memory polymers (SMPs) showed dominance in the former two methods of modification while the latter was suitable for all of the smart materials. This review aims to provide a summary on the state of biodegradable smart polymer research and showcase the overall progress. The authors hope to help in identifying research gaps for potential novelty and inspire new breakthroughs.