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Concentrations of polycyclic aromatic hydrocarbons (PAHs) from a dry extract of fresh and smoked body parts of Clarias gariepinus were examined to determine associated potential human health risks. Gas chromatography analysis was employed for the PAHs determination. The PAHs levels ranged from 0.001 µg/kg [indeno (1,2,3-cd)pyrene] to 11.7 µg/kg (acenaphthene) in fresh (extract), while the smoked (extract) showed 0.001 µg/kg [indeno (1,2,3-cd)pyrene] to 12.7 µg/kg (pyrene). The liver and head smoked were observed to be more contaminated as compared to fresh parts. Individual PAHs in the fish parts were less than the 12.0 µg/kg limit in food as set by the European Union (EU). Although there was evidence of contamination, the potential health risk associated with the fish consumption revealed no observable potential health risk to consumers.

One of the main limitations to the economic sustainability of biodiesel production remains the high feedstock cost. Modeling and optimization are crucial steps to determine if processes (esterification and transesterification) involved in biodiesel production are economically viable. Phenomenological or mechanistic models can simulate the processes. These methods have been used to simulate and manage the processes, but their broad use has been constrained by computational complexity and numerical difficulties. Therefore, it is necessary to use quick, effective, accurate, and resilient modeling methodologies to simulate and regulate such complex systems. Data-driven computational and machine-learning (ML) techniques offer a potential replacement for conventional modeling methodologies to deal with the nonlinear, unpredictable, complex, and multivariate nature of biodiesel systems. Artificial neural networks (ANN) and adaptive neuro-fuzzy inference systems (ANFIS) are the most often utilized ML tools in biodiesel research. To effectively attain maximum biodiesel yield, suitable optimization techniques based on nature-inspired optimization algorithms need to be integrated with these tools to obtain the best possible combination of various operating variables. Future research should focus on utilizing ML approaches for monitoring and managing biodiesel production systems to increase their effectiveness and promote commercial feasibility. Thus, the review discusses the various ML techniques used in modeling and optimizing biodiesel production systems.

Abstract For the first time, a novel mercaptosuccinic acid‐capped tungsten telluride quantum dot (MSA‐WTe3‐QD)‐based electrochemical aptasensor was designed for the determination of SARS‐CoV‐2 N‐protein in synthetic human serum, plasma and urine. The MSA‐WTe3‐QD which exhibited spherical morphology and an average diameter of 3.56 nm were synthesized through a bottom‐up approach. The aptasensor was prepared by firstly immobilizing MSA‐WTe3‐QD on a screen‐printed carbon electrode (SPCE) by using the 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide/N‐hydroxysuccinimide (EDC/NHS) coupling chemistry. Thereafter, amine‐terminated 90‐mer ssDNA aptamer was deposited on the modified SPCE and left to cure to form the aptasensor. Using the chronocoulometry signal transduction technique, the aptasensor's calibration with N‐protein gave a linear range value of 1–9 pg.mL−1 and a limit of detection (LOD) value of 0.08 pg.mL−1. The LOD value of the aptasensor was 8 times lower than the LOD value of 0.71 pg.mL−1 obtained with a commercial N‐protein ELISA kit. When tested in simulated real samples the aptasensor recovery rates of 95–103.33 % were obtained. In the presence of various interferents, the aptasensor displayed good selectivity to N‐protein.

Microplastics (MPs) are emerging pollutants that constitutes a very serious environmental nuisance and menace to the globe in the last decade. The environmental damages from MPs include ecological imbalance of the marine environment, flora, and fauna and these are yet to be understood in the African environment. The sustainable development goals 14 and 15 (SDGs #14 and #15) seek to address the challenges in combating the sustainability of marine and terrestrial lives respectively. Understanding the pollution dynamics of MPs in the environment is crucial to the sustainability of lives globally and in particular Africa soon. Hence, it is imperative to arrest this environmental challenge as swiftly as possible before the collapse of the entire biomes. MPs have been detected in several matrices; soil, air, aquatic environments, plants, fishes, animals, and humans. Their different source routes: ingestion, inhalation, and dermal contact contribute an adverse effect (toxicity) to all spheres of life. To aquatic animals, terrestrial animals, and humans, it limits their movement, leads to the shedding of scales, inhibits growth, suppresses the immune system, and causes inflammation, coagulation, also blood cell toxicity among others, and on the long-run mortality was noted in this review. There is physical, chemical and biological transformation as microplastics age, leading to toxicity, mobility, and great environmental interaction. This has contributed to high MP intake by fish and other aquatic animals. For this reason, researchers should delve into simpler and cheaper ways of analyzing its presence in the environment and develop remediation strategies to curb its presence in the aquatic environment.

Background: Since the onset of the global pandemic, unemployment has increased to new levels. As a consequence, the need to stimulate economic growth through the development of the micro-enterprise sector has become a central vehicle to decrease unemployment and stimulate economic growth. The problem, however, is that despite the potential benefits of digitisation, the micro-enterprise sector has been unable to effectively integrate information and communication technologies (ICTs) into the fabric of their operations. Objectives: The objective of this study was to investigate the factors that influence the adoption and use of mobile applications for micro-enterprise operations in South Africa. Method: A quantitative methodology using a survey design was used to collect data from a sample of entrepreneurs, with 221 responses. Results: Performance expectancy (PE) and effort expectancy (EE) positively influence the micro-entrepreneurs’ behavioural intention (BI) to adopt and use mobile applications, while social influence (SI) has no impact on the same. Facilitating conditions (FC) and BI are the strongest determinants of mobile application adoption and use for micro-enterprise operations. Conclusion: All the constructs of the unified theory of acceptance and use of technology (UTAUT) model showed a satisfactory level of reliability and discriminant validity, which was confirmed by testing the measurement model against two competing models. The UTAUT model is a good predictor of the intention to adopt and use mobile applications for micro-enterprise operations. Contribution: The findings provide parameters to develop a focussed strategy to catalyse the adoption and subsequent use of mobile applications among micro-entrepreneurs. It further informs initiatives to close the gap of a known reluctance in using technology among micro-enterprises.

Background: Herbs have gained recognition as highly efficient tools in the treatment and management of diseases both in modern and traditional medicine. Datura stramonium is a good example of such a medicinal herb. D. stramonium is popularly called thorn apple or Jimson weed in the family of Solanaceae. It has both toxic as well as medicinal potentials. D. stramonium leaves, seeds, and stems have been extensively studied for various pharmacological properties. D. stramonium seed is among the top plants commonly abused as a drug by Nigerian youths. Chemical constituents are responsible for the medicinal potential of plants. Objectives: This study was planned to investigate and compare the vitamin contents of ethanol extract of D. stramonium leaf and seed. Methods: The determination of vitamin levels was carried out using the Association of Official Analytical Chemists (AOAC) and other standard methods. Results: The order of vitamin composition in both leaves and seeds was E>C>A>B6>B9>B12>B2>B1>B3 . Moreover, the concentration of vitamins E, C, and A, being the most abundant, was 6.65:1.64 mg/100 g, 3.65:1.05 mg/100 g, 2.38:1.82 mg/100 g, for leaf and seed extracts, respectively. Further, there were significant differences (P

AbstractOne of the prominent complications observed in those undergoing treatment with methotrexate (MTX) is hematological profile alterations which could culminate in severe anemia. In this study, we assessed the hematological profile indices in MXT-treated rats and the effect of leaf extract of Datura stramonium (LEDS) supplementation in MXT-treated rats. Ethanol (98%) was the solvent used in extraction. Animals were divided at random into four groups. Animals in group 1 received normal saline (5 mg/kg) orally and feeding was limitless and did not receive MXT. Animals in group 2 were given LEDS orally (200 mg/kg body weight) for 21 days while group 3 received 20 mg/kg body weight (bw) of MXT on day 18 via the intra-peritoneum without LEDS. Rats in group 4 were given the extract (200 mg/kg bw) and also injected with 20 mg/kg bw of MXT on day 18 of the study via the intra-peritoneum. Serum levels of hemoglobin, red blood cells, packed cell volume, total white blood cells, neutrophils, lymphocytes, and platelets were determined. Rats treated with MXT had notable depletion in hemoglobin, red blood cells, packed cell volume, total white blood cells, neutrophils, and platelets, unlike the control group. Interestingly, LEDS supplementation markedly restored the altered hematological profiles. MXT injection caused hematological dysfunction while co-supplementation with LEDS restored the impaired hematological indices. Therefore, LEDS could be a promising tool in arresting hematological dysfunctions accompanying MXT chemotherapy. However, we advocate for further prospective scrutiny.

Abstract Background Mycobacterium tuberculosis, a bacterium that relies on its human host to achieve airborne transmission and existence, is the primary cause of tuberculosis (TB), a disease that is vital to public health. Aim To update the society on tuberculosis diagnostic and treatment delays among patients in Uganda. Materials and Methods The review paper utilized different search engines, such as Pubmed Central, Scopus, Web of Science, Google Scholar, and so forth, to conduct this review paper. Results Delays in diagnosis could cause diseases to spread throughout the community, progress more quickly, and increase mortality. With many populations experiencing TB diagnostic delay and less than a third of the population experiencing TB treatment delay, the rates of tuberculosis diagnosis and treatment delays are high. Conclusion The delay in diagnosing and treating tuberculosis in men is positively correlated with knowledge of the disease's symptoms and the regular use of a handkerchief or both hands to cover the mouth and nose while coughing or sneezing.

A novel conceptual design for the co-production of biomethane and propylene glycol from integrated catalytic transfer hydrogenolysis (CTH), biogenic CO2 capture and biomethanation reaction was presented in this study. Furthermore, process economics and environmental impact study was performed to appraise the feasibility of the proposed design. The minimum selling price (MSP) of propylene glycol produced considering the overall cost of biomethane as co-product is 1.41 U.S.$/kg. However, if the cost of biomethane was not considered or if the biomethane produced is not enough to yield a yearly revenue then the MSP would increase to 1.43 U.S.$/kg. The MSP of biomethane for the integrated process was 148 U.S.$/MWh. The MSPs of propylene glycol and biomethane were comparable with those of the business-as-usual technology. Factors such as hydrogen donor solvent cost, catalyst cost, electricity price and equipment purchase cost influenced the MSP. Environmental assessment studies showed that the standalone CTH had a higher overall carbon footprint (carbon emissions of 3.7 MM tonnes/yr.). This could be attributed to the consumption of CO2 derived from the process streams via biomethanation process.

Poly(3-hexylthiophene-2,5-diyl) (P3HT) chains were grown on the surface of thiophene functionalized polypropylenimine tetramine (PPI-TH) and N-methylpyrrole functionalized polypropylenimine tetramine (PPI-PY) using chemical oxidation polymerization. After growing the P3HT chains on the surface of PPI-TH and PPI-PY, the properties of the resulting co-polymers were compared with those of linear P3HT as a reference. P3HT, poly(3-hexylthiophene-2,5-diyl)-co-thiophene functionalized polypropylenimine tetramine (P3HT-T), and poly(3-hexylthiophene-2,5-diyl)-co-N-methylpyrrole functionalized polypropylenimine tetramine (P3HT-P) were characterized by nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), ultraviolet-visible spectroscopy (UV-Vis), scanning electron microscope (SEM), photoluminescence and electrochemical methods. P3HT-T and P3HT-P showed new imine bands on FTIR spectra, change in morphology and optical bandgaps, Stokes shifts, decrease in LUMO energy gap values, and increase in conductivity compared to P3HT. In addition, organic solar cells (OSCs) based on P3HT, P3HT-T, and P3HT-P as donor materials are discussed in this work. In comparison with P3HT-based OSC, the P3HT-T and P3HT-P based OSCs have improved performance due to an increase in VOC and FF. Electrochemical impedance spectroscopy (EIS) and Tafel plots confirmed a reduction in charge recombination and an increase in charge transport for P3HT-T and P3HT-P devices.