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1.
PLoS One ; 19(1): e0293563, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38252674

RESUMO

Africa has been known to experience series of problems among which are poverty, food insecurity, lack of access to energy, lack of infrastructure among others. These problems were exacerbated by the COVID-19 pandemic, which has had a severe impact on the socioeconomic status of households in Africa. This paper examines the relationship between socioeconomic shocks, social protection, and household food security during the pandemic in Nigeria, the Africa's largest economy. Using the World Bank's COVID-19 national longitudinal baseline phone survey (2020) for the analysis and applied the multinomial logit regression, the study finds that socioeconomic shocks resulting from the pandemic have led to an increased level of food insecurity. Social protection programmes have played a crucial role in mitigating the impact of these shocks on households. However, the study also highlights the need for more targeted and effective social protection policies to ensure that vulnerable households are adequately protected from the adverse effects of the pandemic. The findings of this study have important implications for policymakers and stakeholders in Africa's largest economy, as they seek to address the challenges posed by the pandemic and promote household food security for the actualisation the United Nations (UN) Sustainable Development Goal (SDG) of food and nutrition security (SDG2). The study, therefore, recommends that efforts be made to preserve food supply chains by mitigating the pandemic's effect on food systems, increasing food production, and looking forward beyond the pandemic by building resilient food systems with the use of social protection interventions.


Assuntos
COVID-19 , Choque , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Política Pública , Nigéria/epidemiologia , Pobreza , Segurança Alimentar
2.
Int J Mol Sci ; 23(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36142543

RESUMO

The azo dye orange II is used extensively in the textile sector for coloring fabrics. High concentrations of it are released into aqueous environments through textile effluents. Therefore, its removal from textile wastewater and effluents is necessary. Herein, initially, we tested 11 bacterial strains for their capabilities in the degradation of orange II dye. It was revealed in the preliminary data that B. subtilis can more potently degrade the selected dye, which was thus used in the subsequent experiments. To achieve maximum decolorization, the experimental conditions were optimized whereby maximum degradation was achieved at: a 25 ppm dye concentration, pH 7, a temperature of 35 °C, a 1000 mg/L concentration of glucose, a 1000 mg/L urea concentration, a 666.66 mg/L NaCl concentration, an incubation period of 3 days, and with hydroquinone as a redox mediator at a concentration of 66.66 mg/L. The effects of the interaction of the operational factors were further confirmed using response surface methodology, which revealed that at optimum conditions of pH 6.45, a dye concentration of 17.07 mg/L, and an incubation time of 9.96 h at 45.38 °C, the maximum degradation of orange II can be obtained at a desirability coefficient of 1, estimated using the central composite design (CCD). To understand the underlying principles of degradation of the metabolites in the aliquot mixture at the optimized condition, the study steps were extracted and analyzed using GC-MS(Gas Chromatography Mass Spectrometry), FTIR(Fourier Transform Infrared Spectroscopy), 1H and carbon 13 NMR(Nuclear Magnetic Resonance Spectroscopy). The GC-MS pattern revealed that the original dye was degraded into o-xylene and naphthalene. Naphthalene was even obtained in a pure state through silica gel column isolation and confirmed using 1H and 13C NMR spectroscopic analysis. Phytotoxicity tests on Vigna radiata were also conducted and the results confirmed that the dye metabolites were less toxic than the parent dye. These results emphasize that B. subtilis should be used as a potential strain for the bioremediation of textile effluents containing orange II and other toxic azo dyes.


Assuntos
Bacillus subtilis , Água Carbonatada , Compostos Azo/química , Compostos Azo/toxicidade , Bacillus subtilis/metabolismo , Benzenossulfonatos , Biodegradação Ambiental , Carbono/análise , Água Carbonatada/análise , Corantes/química , Glucose , Hidroquinonas , Naftalenos/análise , Sílica Gel , Cloreto de Sódio , Vapor/análise , Têxteis , Ureia , Águas Residuárias/química , Água/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-36011598

RESUMO

Water pollution due to textile dyes is a serious threat to every life form. Bacteria can degrade and detoxify toxic dyes present in textile effluents and wastewater. The present study aimed to evaluate the degradation potential of eleven bacterial strains for azo dye methyl red. The optimum degradation efficiency was obtained using P. aeruginosa. It was found from initial screening results that P. aeruginosa is the most potent strain with 81.49% degradation activity and hence it was subsequently used in other degradation experiments. To optimize the degradation conditions, a number of experiments were conducted where only one variable was varied at a time and where maximum degradation was observed at 20 ppm dye concentration, 1666.67 mg/L glucose concentration, 666.66 mg/L sodium chloride concentration, pH 9, temperature 40 °C, 1000 mg/L urea concentration, 3 days incubation period, and 66.66 mg/L hydroquinone (redox mediator). The interactive effect of pH, incubation time, temperature, and dye concentration in a second-order quadratic optimization of process conditions was found to further enhance the biodegradation efficiency of P. aeruginosa by 88.37%. The metabolites of the aliquot mixture of the optimized conditions were analyzed using Fourier transform infrared (FTIR), GC-MS, proton, and carbon 13 Nuclear Magnetic Resonance (NMR) spectroscopic techniques. FTIR results confirmed the reduction of the azo bond of methyl red. The Gas Chromatography-Mass Spectrometry (GC-MS) results revealed that the degraded dye contains benzoic acid and o-xylene as the predominant constituents. Even benzoic acid was isolated from the silica gel column and identified by 1H and 13C NMR spectroscopy. These results indicated that P. aeruginosa can be utilized as an efficient strain for the detoxification and remediation of industrial wastewater containing methyl red and other azo dyes.


Assuntos
Pseudomonas aeruginosa , Águas Residuárias , Compostos Azo/química , Bactérias , Ácido Benzoico/análise , Ácido Benzoico/metabolismo , Biodegradação Ambiental , Corantes/química , Cromatografia Gasosa-Espectrometria de Massas , Águas Residuárias/química
4.
Heliyon ; 5(8): e02368, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31485542

RESUMO

Understanding the tanker driver hazard awareness on chemical exposure is important to ensure that they are fortified with the appropriate information regarding the risk of their occupation. This present study was conducted to determine the awareness of the petrol tanker driver on the chemical exposure during transportation petroleum product. The assessment on hazardous awareness of the petrol tank driver was conducted through questionnaire survey. Wherein, the questionnaire was designed with considering the variables of age of the driver, working experience, working hours in a day and knowledge on chemical hazard presence in the petroleum oil. A reliability test of Cronbach's Alpha was performed to validate the questionnaire and the Chi-Square test was conducted to determine the correlation among the studied variables. The findings of the present study revealed that the drivers who are frequently come into direct contact with petrol cannot identify the spillage had occurred during working. The study identified that there is an urgency to conduct training on safe handling of petroleum oil in order to eliminate the risk of chemical hazards exposure to the tanker driver.

5.
PLoS One ; 14(5): e0216878, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31091269

RESUMO

The adsorption of rhodamine B (RhB) using acid modified banana peels has been examined. Chemical characteristics of the adsorbents were observed in order to determine active functional groups. The major functional groups on the surface were OH, C = O, C = C and C-O-C. Interactions between operational parameters were studied using the central composite design (CCD) of response surface methodology (RSM). The predictions of the model output indicated that operational factors influenced responses at a confidence level of 95% (P<0.05). The optimum conditions for adsorption were pH 2 at a 0.2 g/L dose within 60 minutes of contact time. Isotherm studies were carried out using the optimized process variables. The data revealed that RhB adsorption fitted the Langmuir isotherm equation while the reduction of COD followed the Freundlich isotherm. Kinetic experiments fitted the pseudo second order model for RhB removal and COD reduction. The adsorption mechanism was not the only rate controlling step. Diffusion through the boundary layer described the pattern of adsorption.


Assuntos
Corantes/química , Frutas/química , Modelos Químicos , Musa/química , Rodaminas/química , Poluentes Químicos da Água/química , Ácidos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica
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