Barriers to implementing the circular economy in the construction industry:A critical review

To facilitate the adoption of the circular economy (CE) in the architecture, engineering and construction (AEC) sector, some authors have demonstrated the potential of recent designs that take into account the sustainable management of an asset’s end-of-life (EOL), providing an alternative to the dominant designs that end with demolition. However, there is no review of the literature that encompasses a large range of sustainable designs in the current CE context. This paper provides a critical review of journal papers that deal with the barriers to implementing sustainable designs and approaches to the EOL management of assets that have the potential to fulfil the principles of the CE. Eighteen approaches related to prefabrication, design for change, design for deconstruction, reverse logistics, waste management and closed-loop systems were found. Through an analysis of the barriers that are common among these 18 approaches, we classified them into six different categories (organisational, economical, technical, social, political and environmental). Two Sankey diagrams illustrate the interrelation between the barriers, their categories and the 18 approaches. The diagrams clearly show that most of the barriers are common to multiple approaches and that most of the barriers relate to organisational concerns. The study gives a detailed map of the barriers that would help stakeholders from the AEC sector develop strategies to overcome the current obstacles in the shift to a CE

Chitosan nanoparticles: a versatile platform for biomedical applications

Chitosan is a biodegradable and biocompatible natural polymer that has been extensively explored in recent decades. The Food and Drug Administration has approved chitosan for wound treatment and nutritional use. Furthermore, chitosan has paved the way for advancements in different biomedical applications including as a nanocarrier and tissue-engineering scaffold. Its antibacterial, antioxidant, and haemostatic properties make it an excellent option for wound dressings. Because of its hydrophilic nature, chitosan is an ideal starting material for biocompatible and biodegradable hydrogels. To suit specific application demands, chitosan can be combined with fillers, such as hydroxyapatite, to modify the mechanical characteristics of pH-sensitive hydrogels. Furthermore, the cationic characteristics of chitosan have made it a popular choice for gene delivery and cancer therapy. Thus, the use of chitosan nanoparticles in developing novel drug delivery systems has received special attention. This review aims to provide an overview of chitosan-based nanoparticles, focusing on their versatile properties and different applications in biomedical sciences and engineering.info:eu-repo/semantics/publishedVersio

Modulation of immune cum inflammatory pathway by earthworm granulation tissue extract in wound healing of diabetic rabbit model

Regeneration is a rare occurrence in the animal kingdom, but the earthworm stands out as a remarkable example of this phenomenon. Recent research has highlighted the promising wound healing properties of extracts derived from earthworms. Therefore, we propose that earthworm granulation tissue extract (EGTE) may facilitate wound healing by regulating immune responses in a rabbit diabetic wound model. Electron microscopy reveals that 70 % EGTE possesses noteworthy porosity with spherical to irregularly oval configuration. Gas chromatography–mass spectrometry (GC–MS) Characterization of EGTE revealed higher levels of ergosta-5,7,22-trien-3-ol, (3. beta.,22E). In-Vitro studies revealed significant anti-oxidant, anti-inflammatory and anti-bacterial properties in dose dependent manner. Likewise, cytotoxicity assessments reveal that 70 % EGTE exhibits minimal harm to cells while displaying substantial antioxidant and anti-inflammatory activities. For In-Vivo studies excision wounds were created on the dorsal regions of the experimental animals and were divided as Group I (50 % EGTE), Group II (70 % EGTE), Group III (vehicle) and Group IV (distilled water). Over a 21-day observation period 70 % EGTE facilitated the early healing of wounds in the experimental animals, evident through prompt wound closure, granulation tissue formation, increased DNA content, enhanced tensile strength of the wound area and enhanced the expression/synthesis of wound healing markers/proteins. From these results it can be postulated that EGTE accelerates wound healing by immune modulation, dampening of inflammatory pathway and enhanced expression of growth markers. Henceforth making it promising candidate for therapeutic use in diabetic wound healing