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Investment in SARS-CoV-2 sequencing in Africa over the past year has led to a major increase in the number of sequences generated, now exceeding 100,000 genomes, used to track the pandemic on the continent. Our results show an increase in the number of African countries able to sequence domestically, and highlight that local sequencing enables faster turnaround time and more regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and shed light on the distinct dispersal dynamics of Variants of Concern, particularly Alpha, Beta, Delta, and Omicron, on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve, while the continent faces many emerging and re-emerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century.

Graphene has been hailed as a revolutionary membrane material because of its many alluring features and the ease in their tunability. In specific to gas separation industry, the exceptional molecular transport, the possibility of fabricating membranes having thickness at a nanoscale range and the robust lattice structure that can withstand to the rigorous perforation methods render graphene to stand ahead of its contemporary materials. Moreover, its broad chemical tolerance and high mechanical strength facilitate the mass-production of membranes possessing macroscopic dimensions and their subsequent long-term operation under harsh environments. In this concise review, we complied and discussed the progress of gas-separation performance of graphene-based membranes with a prime focus on recent advancements in scalability, functionalization/modification along with the new manufacturing processes including the budding approaches through synthetic chemistry. The strategies implemented, the factors that influenced the membranes'performance and the corresponding transport mechanisms were highlighted in detail. In the end, we outlined the daunting challenges facing by these graphene-based membranes in realization of their prospects as well as the proposed measures for alleviating them.

Bacterial cellulose (BC) is a polysaccharide known as a suitable matrix for proper wound healing. To improve this ability, BC was functionalized with silk sericin (SS) that has cytoprotective and mitogenic effects. The composites obtained by solution impregnation were stabilized by hydrogen bonds, and SS could be released in a controlled manner. The constructs were highly porous with interconnected pores allowing for high water uptake that varied with the SS concentration used for sample preparation. While SS did not disrupt the stability of the BC network, soluble SS diffusing from the composites did not influence keratinocyte growth but enhanced fibroblast proliferation, which would further optimize the wound healing process and improve extracellular matrix production, accelerating healing. Further, improved cell viability was observed upon the composites. Because of their attractive structure and properties, these BC-SS biomaterials represent potential candidates not only for wound dressing applications but also for tissue engineering.

Graphical abstract