Search

Molecular modelling and simulation were used to examine the efficacy of iron nanoparticles (Fe3O4–NPs) in removing amoxicillin (AMX) from aqueous media and determine the optimal conditions. Fe3O4–NPs were initially ascertained using scanning electron microscopy, and Fourier transform infrared spectroscopy. The molecular optimisation modelling via DFT confirmed AMX molecule has chemical potential (–3.59), and electrophilicity index (2.14). The results established that a small chemical hardness = 3.0 eV and molecular energy gap of 6.01 eV, which makes it reactive. The molecule of the antibiotics could interact and be absorbed by the lactase enzyme. The parameters: pH (3–7), time (15–80 min), Fe3O4–NPs dosage (0.1–1.0 g/L), and antibiotic concentration (10–100 mg/L) were studied. The impact of optimum variables pH3, and dosage (0.5 g/L) for adsorption of AMX molecules onto coated Fe3O4–NPs translated to 98% efficiency at 60 mg/l of AMX and 60 min. The adsorption data fitted the Langmuir (R2: 0.9245) with minimal error metrics RMSE ≤ 1.2 when compared to the Freundlich isotherm R2 (0.88) and intraparticle diffusion model R2 (0.58). The maximum adsorption capacity of AMX to Fe3O4–NPs corresponds to 6.47 mg/g with a corresponding adsorption constant of 2.8. Furthermore, AMX adsorption onto Fe3O4–NPs followed pseudo-second-order at R2 (0.9999), with an adsorption constant (k = 3.6 × 10−2g/mg.min). [ABSTRACT FROM AUTHOR]

This study examined the modelling and optimisation of the electrocoagulation-flocculation (ECF) recovery of aquaculture effluent (AQE) using aluminium electrodes. The response surface methodology (RSM), artificial neural network (ANN), and adaptive neuro-fuzzy inference system (ANFIS) were used for the modelling, while the optimisation tools were the numerical RSM and genetic algorithm (GA). Furthermore, the kinetics of the ECF process was studied to provide insight into the mechanism governing the ECF of AQE. The experimental design was performed using the central composite design (CCD) of the RSM. The ANFIS modelling was accomplished via the Grid Partition (GP) of the data set, while the ANN used the multi-layer perceptron (MLP) based feed-forward system. Statistically, the prediction accuracy of the models followed the order: ANFIS (R2: 0.9990), ANN (R2: 0.9807), and RSM (R2: 0.9790). The process optimisation gave optimal turbidity (TD) removal efficiencies of 98.98, 97.81, and 96.01% for ANFIS-GA, ANN-GA, and RSM optimisation techniques, respectively. The ANFIS-GA gave the best optimization result at optimum conditions of pH 4, current intensity (3 A), electrolysis time (7.2 min), settling time (23 min), and temperature (43.8 °C). In the kinetics study, the experimental data was analysed using pseudo-first-order (0.8787), pseudo-second-order (0.9395), and Elovich (R2: 0.9979) kinetic models; the Elovich model gave the best correlation with the experimental data showing that the process is governed by electrostatic interaction mechanism. This study effectively demonstrated that ECF recovery of AQE can effectively be modelled using RSM, ANN, and ANFIS and be optimised using RSM, ANN-GA, and ANFIS-GA techniques, and the order of performance is ANFIS > ANN > RSM and ANFIS-GA > ANN-GA > RSM, respectively. [ABSTRACT FROM AUTHOR]

In recent years, many researchers have focused on the cognitive aspects and mental structures of the managers to identify the strategies. They claim that in order to become familiar with how strategies are formulated and developed, they should evaluate the mind of the strategists and somehow decode the black box. Therefore, the present study aimed to understand the managers' strategic thinking process and to investigate the similarities in their thinking processes. Semi-structured interviews were conducted based on Zaltman metaphor elicitation technique (ZMET) interviews process. Interviews were conducted with 18 managers from two dairy industry companies. The data were analyzed based on emerging approach to grounded theory. The results of this study demonstrated that the managers of a company are using a shared mental model during strategic thinking. This similarity in their thinking process can be considered to be due to their communications and collaborative work experience. In addition, comparing the common mental model in the two companies, no significant similarity was found in their thinking process. But, there are some similarities between the mental structures of the managers of the two companies. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate biogenic amine production in different types of cooked protein foods. The food samples were incubated at varying temperatures (4, 37 and 55 °C) on different microbiological media for 48, 72 and 180 h. Resulting bacteria were isolated and characterized using cultural, biochemical and molecular methods, further screened for production of biogenic amines in decarboxylase broth media supplemented with 0.4% of histidine, tyrosine, lysine and ornithine. The samples were incubated at 25 °C for 48 h and the biogenic amine concentration in each food sample determined by means of HPLC. There was a high prevalence of the isolates among the food samples. All the isolates except Klebsiella sp. and Pseudomonas sp. were positive for decarboxylase activity indicating 84.6% of the isolates capable of biogenic amine production. The amine concentration varied among the types of food and methods of cooking. Histamine was detected in 41.67% of the inoculated food samples (9.2 ± 1.2–100.95 ± 0.1 µg/g) while putrescine was the least detected (41.67%) in the inoculated food sample (7.7 ± 0.1–8.8 ± 0.2 µg/g). Cadaverine and histamine were detected in 16.4% (2.6 ± 0.2–49.9 ± 0.9 µg/g) and 7.5% (1.4 ± 0.1–20.4 ± 0.3 µg/g) of the foods, respectively. Microbial contamination of the cooked protein foods led to high levels of biogenic amines irrespective of the cooking methodology adopted and type of foods investigated. [ABSTRACT FROM AUTHOR]

This current study review provides a brief review of a natural bee product known as propolis and its relevance toward combating SARS-CoV viruses. Propolis has been utilized in medicinal products for centuries due to its excellent biological properties. These include anti-oxidant, immunomodulatory, anti-inflammatory, anti-viral, anti-fungal, and bactericidal activities. Furthermore, studies on molecular simulations show that flavonoids in propolis may reduce viral replication. While further research is needed to validate this theory, it has been observed that COVID-19 patients receiving propolis show earlier viral clearance, enhanced symptom recovery, quicker discharge from hospitals, and a reduced mortality rate relative to other patients. As a result, it appears that propolis could probably be useful in the treatment of SARS-CoV-2-infected patients. Therefore, this review sought to explore the natural properties of propolis and further evaluated past studies that investigated propolis as an alternative product for the treatment of COVID-19 symptoms. In addition, the review also highlights the possible mode of propolis action as well as molecular simulations of propolis compounds that may interact with the SARS-CoV-2 virus. The activity of propolis compounds in decreasing the impact of COVID-19-related comorbidities, the possible roles of such compounds as COVID-19 vaccine adjuvants, and the use of nutraceuticals in COVID-19 treatment, instead of pharmaceuticals, has also been discussed. [ABSTRACT FROM AUTHOR]