STATISTICAL OPTIMIZATION AND SENSITIVITY ANALYSIS OF RHEOLOGICAL MODELS USING CASSAVA STARCH

Models are sometimes employed to determine some parameters that can be used to distinguish between different types of food samples. Rheological models can be used to predict flow for severe conditions where it is difficult to determine the nature of the fluid flow, consequently it is essential to select the appropriate rheological models. This study aims to propose a rheological model that describes an ideal cassava starch rheological behavior and its influence on state variables such as concentration and temperature in order to validate the rheological models. In this study, five rheological models (namely; Power-law model, Robertson-stiff model, Herschel-Bulkey model, Prandtl-Eyring model and Bigham plastic model) were amended into various statistical model by adding the error variance (e). This study concludes that Herschel-Bulkley model and Robertson-stiff model closely explain the rheological patterns occurring during the production of cassava starch. The sensitivity evaluation of other rheological models demonstrate that the validity of Power-law model, Herschel-Bulkley model and Robertson stiff model is not notably influenced by changes in concentration and temperature of the cassava starch. Nevertheless, the Prandtl-Eyring and Bingham plastic models are noted to have less reliable prediction at lower temperature and higher concentration respectively

Appraisal of Natural Durability of a Lesser – Known Boscia anguistifolia (A. Rich) Wood Using Ground Contact Test

The optimal utilization of lesser-known wood species is dependent on their natural durability. In this study, the natural durability of a lesser-known wood species (Boscia anguistifolia) using ground contact test was carried out. Wood blocks of Boscia anguistifolia and Ceiba petandra (reference species) with dimensions of 20 x 20 x 300 mm were obtained from the axial and radial direction of the trees. The wood blocks were conditioned and their moisture content determined before exposure to ground contact for 12 weeks after which their weight loss was determined. Data obtained were analysed using analysis of variance (ANOVA) at 0.05 probability level. The moisture content of B. anguistifolia and C. petandra ranged from 12.80 – 18.02 % and 12.73- 16.63%, respectively while the weight loss of B. anguistifolia and C. petandra ranged from 5.10 – 69.11% and 37 – 50 % respectively along the axial position. It was observed that the core wood in the base portion of B. anguistifolia has the lowest weight loss value of 5.10% while the reference species has a value of 39.73%. Conclusively, B. anguistifolia is moderately durable at the base part of the species when compared with the reference non-durable species used in this study

Optimization and Isothermal Studies of Antibiotics Mixture Biosorption From Wastewater Using Palm Kernel, Chrysophyllum albidum, and Coconut Shells Biocomposite

The presence of persistent pharmaceutical products in water bodies is a significant problem that obstructs wastewater reuse. This study investigated the adsorption process for removing the recalcitrant antibiotics, including tetracycline (TC), ampicillin (AMP), and amoxicillin (AMOX) from an aqueous solution using a composite biosorbent made from a mixture of palm kernel shell (PKS), Chrysophyllum albidum (CAS), and coconut shell (CS). Simplex centroid design in the Design of Expert (12.0.1.0) was applied to optimize the percentage composition (20-55%) of the composite biosorbent precursor and to remove TC-AMP-AMOX mixtures from the aqueous solution in a batch study. The equilibrium data were fitted to 12 isotherm models and analyzed statistically. The maximum adsorption capacity of 9.12 mg/g, 8.66 mg/g, and 7.11 mg/g was achieved for TC, AMP, and AMOX, respectively, using the biocomposite biosorbent with an optimal mixture of 55% PKS, 20% CAS, and 25% CS. The adsorption behavior of TC, AMP, and AMOX was well-described by the Langmuir/Elovich isotherm (R2=1.000), Hill-DeBoer (R2=0.9953), and Freundlich/ Halsey (R2=0.9898) models, respectively. The obtained results showed that the biocomposite PKS-CAS-CS leverages the individual adsorptive capacity of each constituent to enhance the adsorption process. Moreover, the composite biosorbent demonstrated excellent potential for removing recalcitrant pharmaceuticals from wastewater effectively

Adsorption mechanism and modeling of radionuclides and heavy metals onto ZnO nanoparticles: a review

Abstract The contamination of environmental waters with heavy metals and radionuclides is increasing because of rapid industrial and population growth. The removal of these contaminants from water via adsorption onto metal nanoparticles is an efficient and promising technique to abate the toxic effects associated with these pollutants. Among metal nanoparticle adsorbents, zinc oxide nanoparticles (ZnONPs) have received tremendous attention owing to their biocompatibility, affordability, long-term stability, surface characteristics, nontoxicity, and powerful antibacterial activity against microbes found in water. In this review, we considered the adsorption of heavy metals and radionuclides onto ZnONPs. We examined the isotherm, kinetic, and thermodynamic modeling of the process as well as the adsorption mechanism to provide significant insights into the interactions between the pollutants and the nanoparticles. The ZnONPs with surface areas (3.93 to 58.0 m2/g) synthesized by different methods exhibited different adsorption capacities (0.30 to 1500 mg/g) for the pollutants. The Langmuir and Freundlich isotherms were most suitable for the adsorption process. The Langmuir separation factor indicated favorable adsorption of all the pollutants on ZnONPs. The pseudo-second-order kinetics presented the best for the adsorption of the adsorbates with regression values in the range of 0.986–1.000. Spontaneous adsorption was obtained in most of the studies involving endothermic and exothermic processes. The complexation, precipitation, ion exchange, and electrostatic interactions are the probable mechanisms in the adsorption onto ZnONPs with a predominance of complexation. The desorption process, reusability of ZnONPs as well as direction for future investigations were also presented

Charting achievements: a two-year retrospective of the society for environmental geochemistry and health (SEGH) and the evolving strategies

Emerging from the shadow of the COVID-19 pandemic, it is time to ground ourselves and retrospectively assess the recent achievements of SEGH over the past years. This editorial serves as a comprehensive report on the progress made in comparison to the aspirations and goals set by the society's board in 2019 (Watts et al., Environ Geochem Health 42:343–347, 2019) (Fig. 1) and reflects on the state of the SEGH community as it reached its 50th anniversary at the close of 2021 (Watts et al. Environ Geochem Health 45:1165–1171, 2023). The focus lies on how the SEGH community navigated through the extraordinary challenges posed by the COVID-19 pandemic since early 2020, and to what extent the 2023 targets have been met

Trypanosoma brucei Glycogen Synthase Kinase-3, A Target for Anti-Trypanosomal Drug Development: A Public-Private Partnership to Identify Novel Leads

Over 60 million people in sub-Saharan Africa are at risk of infection with the parasite Trypanosoma brucei which causes Human African Trypanosomiasis (HAT), also known as sleeping sickness. The disease results in systemic and neurological disability to its victims. At present, only four drugs are available for treatment of HAT. However, these drugs are expensive, limited in efficacy and are severely toxic, hence the need to develop new therapies. Previously, the short TbruGSK-3 short has been validated as a potential target for developing new drugs against HAT. Because this enzyme has also been pursued as a drug target for other diseases, several inhibitors are available for screening against the parasite enzyme. Here we present the results of screening over 16,000 inhibitors of human GSK-3β (HsGSK-3) from the Pfizer compound collection against TbruGSK-3 short. The resulting active compounds were tested for selectivity versus HsGSK-3β and a panel of human kinases, as well as their ability to inhibit proliferation of the parasite in vitro. We have identified attractive compounds that now form potential starting points for drug discovery against HAT. This is an example of how a tripartite partnership involving pharmaceutical industries, academic institutions and non-government organisations such as WHO TDR, can stimulate research for neglected diseases