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Natural gas, coal, and oil account for over 84 % of the world’s energy demand. Greenhouse gases, including carbon dioxide, methane, and oxides of nitrogen and sulphur, are released during the combustion of fossil fuels, leading to substantial climate changes and environmental damage. Therefore, harnessing energy from alternative sustainable resources without the emission of harmful waste products is vital for the ecosystem’s health. By 2050, global food waste production will reach 3.4 billion metric tons. Although widely recognized as a substantial energy resource, its value is underutilized throughout sub-Saharan Africa (SSA). Therefore, understanding and exploiting the potential value of food waste as a biofuel can result in net-zero emissions, reducing significant environmental pollution while conserving natural resources. Furthermore, this paper reviews how effective management of food waste will have the potential to contribute to the development of waste-to-energy resources in SSA countries, as well as help improve global ecosystems.

Becker muscular dystrophy (BMD) is a progressive disorder and impairs upper extremity (UE) function. The Performance of Upper Limb (PUL) measures UE function in muscular dystrophy, but has a ceiling effect in high-functioning subjects. Yet, fat fraction (FF) values via quantitative magnetic resonance (qMRI) have been used as biomarkers of muscle deterioration. Thus, the study aims to 1) determine if the PUL or qMRI FF can discriminate between functional groups of men with BMD and controls, and 2) assess relationships between PUL scores and qMRI FF. In a cross-sectional study, 56 men with BMD and 9 controls (18-63 yrs) completed PUL 2.0 and whole-body qMRI. Composite FF values for UE (deltoid, biceps & triceps) and whole-body were calculated. To understand the impact of mobility on UE performance, men with BMD were grouped using the 10-m run/walk test. Functional groups were: A) non-ambulatory B) walks – with no increase in speed possible; C) fast walking or jog; or D) run. One-way ANOVA/Kruskal-Wallis and Spearman's rho were used to assess differences between groups and correlations, respectively. Men with BMD scored 18-42 on the PUL. The PUL only detects differences between non-ambulatory (Group A) and high-functioning (Group C: p<0.001; Group D: p=0.02; Controls: p<0.001) groups. However, qMRI UE FF composite can discriminate between low-functioning (Groups A-B) and high-functioning (Groups C-D) men with BMD and whole-body FF composite can discriminate between all BMD functional groups (p<0.001 to 0.02). Higher PUL scores were associated with lower qMRI FF (p<0.05; rho =-0.70 to -0.50) only in low-functioning men with BMD (Groups A&B). Thus, the PUL has utility in assessing UE function in low-functioning men with BMD. Because the PUL may provide limited information about UE impairment in high-functioning men with BMD, it should be used cautiously or together with other biomarkers such as qMRI FF. [ABSTRACT FROM AUTHOR]

Becker muscular dystrophy (BMD) results in fat replacement of skeletal muscle and impaired functional performance. Quantitative magnetic resonance (qMR) imaging of muscle fat fraction (FF) has been used as a biomarker of muscle deterioration in muscular dystrophies. Specifically, qMR whole-body imaging (WBI) can quickly analyze multiple muscles and develop FF composites. The North Star Assessment for limb-girdle type muscular dystrophies (NSAD), has the potential to assess motor function in men with BMD across a wide range of abilities. Thus, we aimed to 1) assess the relationship between qMR FF and NSAD scores, and 2) determine qMR FF cut-off values for loss of performance on NSAD tasks that require gluteal and thigh muscle contractions. 41 men with BMD (18-62 years) completed 3-point Dixon qMR WBI and the NSAD. GlutThigh was calculated as the average FF of the right gluteus maximus, gluteus medius/minimus, quadriceps femoris, and hamstrings. The relationship between GlutThigh and function was assessed using Spearman's rho. GlutThigh cut-off values to discriminate men able or unable to perform each NSAD task were calculated using the receiver operating characteristic (ROC) and the Youden Index. Men with BMD had GlutThigh values from 0.08-0.89 (median: 0.58). Higher GlutThigh was strongly associated with lower NSAD scores (rho=-0.93; p<0.001). GlutThigh cut-off values ranged from 0.27 for rise from squat and running to 0.82 for standing and showed 83-100% sensitivity and 67-100% specificity. In men with BMD, higher GlutThigh values are strongly associated with poorer NSAD performance and more challenging NSAD tasks have lower GlutThigh cut-offs. GlutThigh cut-off values have high sensitivity and specificity to detect NSAD task failures across a wide range of men with BMD. Thus, qMR WBI GlutThigh provides important insight into functional performance in men with BMD and may serve as a functionally relevant biomarker of disease status in future clinical trials. [ABSTRACT FROM AUTHOR]

Microwave simulation is significant in identifying a reactor design allowing the biomass to be heated and processed evenly. This study integrated the radio frequency and transient heat transfer modules to simulate the microwave distribution and investigated the performance of microwave heating in the cavity. The simulation results were compared with the experimental findings using the finite element analysis software of COMSOL MULTIPHYSICS to predict the temperature profile and electric field of microwave in the biomass (empty fruit bunch pellets). The higher temperature distribution was observed at the bottom and centre section of the empty fruit bunch pellet bed in the reactor, showing the uniqueness of microwave heating. According to the simulation results, the temperature profile obtained through the specific cavity geometry and dielectric properties agreed with the experimental temperature profile. The simulated temperature profile demonstrated a logarithmic increase of 120 °C/min at the first 50 s followed by 50 °C/min until 350 s. The experimental temperature profile showed three different heating rates before reaching 300 °C, including 78.3 °C/min (50–120 °C), 30.6 °C/min (121–250 °C), and 105 °C/min (250–300 °C). The results of this study might contribute to the improvement of microwave heating in biomass torrefaction.

The presence of toxic heavy metals contributes towards the deterioration in the quality of water resources. In this work, microwave steam activation (MSA) was conducted to convert palm kernel shell into activated carbon (PKSAC). MSA provided a rapid heating rate (up to 140 °C/min) at 700 °C under a steam flow rate of 5 g/min for 45 min. PKSAC was obtained, showing high BET surface area (539.75 m2/g) with low H/C and O/C ratios, indicating a high degree of carbonization and stability of PKSAC to act as a durable adsorbent. The PKSAC was then applied to remove heavy metals (i.e. Cd2+ and Pb2+) present in landfill leachate (LL). Batch experiments were performed to investigate the effects of initial ion concentrations and contact times on Cd2+ and Pb2+ adsorption under optimal condition. Maximum Cd2+ and Pb2+ removal of 116.0 mg/g and 59.9 mg/g, respectively were obtained at pH 3, initial concentration of 100 mg/L, and adsorbent dose of 0.2 g. Results showed that the adsorption kinetics of Cd2+ and Pb2+ can be described by the pseudo second order kinetics model, while Freundlich isotherm was well fitted to the Cd2+ and Pb2+ adsorption data. Overall, the PKSAC produced by MSA is a promising and cost-effective adsorbent for removal of Cd2+ and Pb2+.

The leishmaniases comprise a complex of diseases characterized by clinical outcomes that range from self-limiting to chronic, and disfiguring and stigmatizing to life threatening. Diagnostic methods, treatments, and vector and reservoir control options exist, but deciding the most effective interventions requires a quantitative understanding of the population level infection and disease dynamics. The effectiveness of any set of interventions has to be determined within the context of operational conditions, including economic and political commitment. Mathematical models are the best available tools for studying quantitative systems crossing disciplinary spheres (biology, medicine, economics) within environmental and societal constraints. In 2005, the World Health Assembly and government health ministers of India, Nepal, and Bangladesh signed a Memorandum of Understanding to eliminate the life threatening form of leishmaniasis, visceral leishmaniasis (VL), on the Indian subcontinent by 2015 through a combination of early case detection, improved treatments, and vector control. The elimination target is <1 case/10,000 population at the district or subdistrict level compared to the current 20/10,000 in the regions of highest transmission. Towards this goal, this chapter focuses on mathematical models of VL, and the biology driving those models, to enable realistic predictions of the best combination of interventions. Several key issues will be discussed which have affected previous modelling of VL and the direction future modelling may take. Current understanding of the natural history of disease, immunity (and loss of immunity), and stages of infection and their durations are considered particularly for humans, and also for dogs. Asymptomatic and clinical infection are discussed in the context of their relative roles in Leishmania transmission, as well as key components of the parasite-sandfly-vector interaction and intervention strategies including diagnosis, treatment and vector control. Gaps in current biological knowledge and potential avenues to improve model structures and mathematical predictions are identified. Underpinning the marriage between biology and mathematical modelling, the content of this chapter represents the first step towards developing the next generation of models for VL. [ABSTRACT FROM AUTHOR]