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The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

Purpose – The purpose of this research is to synthesize modified thermoplastic sago starch (TPS) through in-situ mechanism by reacting sago starch with diphenylmethanediisocyanate (MDI) and castor oil simultaneously, resulting in a more homogenous and finer-sized polyurethane prepolymer (PUP).

Design/Methodology/Approach – The methods used were Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) for thermal characterization and stability of PUP, modified TPS non-extracted and extracted with toluene and water.

Findings – TGA test results presented shows that PUP begins to decompose thermally at a temperature of 300–500 °C. Weight loss occurs rapidly between these temperatures and is completely discharged at a temperature of 500°C, which is called weight loss transition.

Research Limitations/Implications – When extracted with toluene and a water solvent, the melting point and latent heat of fusion slightly decreased; however, it is still higher than the original value of sago. In terms of thermal stability, modified TPS decomposes and loses weight at 150–200 °C in small quantities, continues with weight loss rapidly, and is completely discharged at 500°C. The thermal stability is considered high; thus, modified TPS application can be varied.

Practical Implications – DSC analysis and TGA shows that modified TPS has good thermal characteristics and thermal stability. Modified TPS has a melting point of 104.69°C, and the latent heat of fusion (ΔH) is 234.27 J/g. This value is close to the PUP melting point and latent heat of fusion, which reveals the formation of cross-link between the starch and PUP.

Purpose – Description of the effects of the revolution in neuroscience and other areas of biology that can help to explain the roots of some portion of violent crime. The chapter reconsiders the role of brain chemistry in social behavior and violent behavior. To illustrate the interdisciplinary complexities entailed when linking brain chemistry to policy decisions concerning violent crime, this analysis has four main stages: first, why might SiFs (H2SiF6 and Na2SiF6, jointly called “silicofluorides” or SiFs) be dangerous? Second, what biochemical effects of SiF could have toxic consequences for humans? Third, on this basis a research hypothesis predicts children in communities using SiF should have increased uptake of lead from environmental sources and higher rates of behavioral dysfunctions known to be caused by lead neurotoxicity.

Design/methodology/approach – To illustrate the implications of the new issues involved, this chapter focuses on a public policy that inadvertently seems to increase rates of violent crime. Since violent behavior is one of the effects of lead neurotoxicity, the hypothesis is tested using multiple sources of data including rates of violent crime studied using a variety of multivariate statistical techniques (including analysis of variance, multiple regression, and stepwise regression).

Findings – Various data sources point to greater violence among individuals with greater exposure to SiFs.

Originality/value – Testing hypotheses linking neurotoxins to violent behavior reveals the generally unsuspected value of analyzing human social behavior and public policy from the perspective of evolutionary psychology.

Preparing for a potential bioterroism is a difficult task for health care leaders because of the fundamental unpredictability of bioterroist acts. Complexity science thinking is presented as an approach that can help in this task. Basic concepts from complexity science, especially the role of relationships, are presented. Specific recommendations for action including sensemaking, learning, and improvisation are made. A case study is used to illustrate the power of complexity science thinking in assisting health care leaders addressing potential bioterroism. Questions for further research are presented.

Every year, tens of millions of the 1.4 billion cars on the world’s roads are decommissioned. While the ferrous and other metals that constitute about 75% of a vehicle by weight can be readily and profitably recycled, the remaining mix of plastics, glass, composites, complex materials, fragments and contaminants are mainly destined for landfill as automotive shredder residue (ASR). For every car, approximately 100–200 kg of ASR is disposed of in landfill, posing a growing technical and environmental challenge worldwide. The recovery of the ASR for high-end application is the focus of this study, aiming to optimise the use of these valuable resources and minimise the extractive pressure for raw materials, a future green manufacturing, contributing towards a zero waste circular economy. As the dissolution of carbon into iron is a key step in the manufacture of iron-carbon alloys, the feasibility of utilizing the waste polymers within ASR as sources of carbon in different areas of pyrometallurgical processing was investigated. Polypropylene and rubber, in a blend with metallurgical coke, were used as carbonaceous substrates and the slag-foaming phenomenon was investigated via the sessile drop technique in an argon environment at 1,550°C. The results indicated the rubber/coke blend achieved significantly better foaming behaviour, and the PP/coke blend exhibited a moderate improvement in slag foaming, in comparison to 100% metallurgical coke. The overall results indicated the incorporation of ASR had significant improvement in foaminess behaviour, increasing furnace efficiency.