34 research outputs found
The Neutrality or Variability of the Nigerian Tax System to Comparative Econometric Models and Economic Growth
This study is set to compare the output of three econometric models â Linear, Log Quadratic and Transcendental Logarithm (Translog) â to evaluate the relationship between tax system and economic growth using the gross domestic product (GDP) as a proxy. The neutrality (the extent to which tax system is indifference to) or variability (the extent to which tax system is inconsistent with) the outputs of the three comparative econometric models used in evaluating the relationship between Nigeria tax system and GDP, is the main thrust of the paper. Findings revealed that the output from the Linear and the Translog models were similar, but the output from Log Quadratic model was different. The choice of an econometric model in evaluating relationship should be carefully decided rather than being arbitrary. It is recommended that two or more mdels may be used, were appropriate, to evaluate the relationship between variables. One of the criteria for selecting appropriate model is a pre- graphical representation of the relationships between the variables. Keywords: Neutrality, Variability, Nigerian tax system, Comparative econometric models, Economic growth
Voltammetric and impedance studies of phenols and Its derivatives at carbon nanotubes/Prussian bluefilms platinum modified electrode
The electrochemical oxidation of phenol (Ph), 4-chlorophenol (4-ClPh) and 4-nitrophenol (4-NPh) at a platinum electrode modified with and without multi-walled carbon nanotubes/Prussian blue nanocomposite in a pH 7.0 phosphate buffer electrolyte was investigated by cyclic voltammetry (CV) and impedance measurements. The modified electrodes were characterised using techniques such as transmission electron microscopy (TEM), electron X-ray dispersive spectroscopy (XRD), cyclic voltammetry (CVs) and electrochemical impedance spectroscopy (EIS)..
Exploring flexible working practices and the digital divide in a post-lockdown era
Purpose
This paper explores flexible working practices (FWPs) and takes a critical view that argues a need to consider not only access to digital technological resources but also the vast array of factors that constrain oneâs ability to use technology for its intended benefits, as constituting the digital divide post-COVID-19 lockdown.
Design/methodology/approach
Using a critical evaluation of the extant literature, we engage in a conceptual undertaking to develop theoretical propositions that form the basis for future empirical undertakings. To theoretically ground the arguments raised, we deploy the ontological lens of actor-network theory to illuminate the socio-technical dimensions of the digital divide in light of FWPs.
Findings
Since the COVID-19 pandemic, the need to adopt socially distanced work practices has become a reality for many organisations. We find that the adoption of FWPs, enabled by digital technologies, simultaneously signals hidden inequalities. We also develop a conceptual framework which depicts user responses in different technology environments that can either be limiting or enabling for individualsâ work productivity.
Originality/value
With regards to the digital divide, attention has often focused on access to digital technologies, as the term âdigital divideâ portrays. The implication is that the array of factors and resources that individuals are heterogeneously networked to, which also constitute the digital divide, is often taken for granted. We take a different ontological view that brings to the fore other factors at play within an individualâs network of relations
Role of Low Environmental Temperature in Peptic Ulcer Development
Peptic ulcers are described as acid-induced lesions found in the stomach and duodenum caused by the imbalance between the defending factors of the mucosa and the attacking factors such as hydrochloric acid in gastric juice, with Helicobacter Pylori (H. Pylori) and Non-Steroidal Anti-Inflammatory Drugs NSAIDs. They exhibit seasonal patterns in their occurrence, with higher occurrence in winter and spring and a low occurrence in summer. Temperature plays a major role in their occurrence, some of which have resulted in increased morbidity in some number of diseases, such as gastrointestinal bleeding, caused by an increase in air pressure, dry air (relative humidity) occurring from cold air, and also its actions on the protective effect helicobacter pylori in the human body. Their actions excite the adrenal gland marrow and the sympathetic nerve, causing rapid secretion of adrenaline and non-adrenaline, angiotensin II and endothelin, resulting in damage to the mucosa epithelial, caused by the contraction effect of the adrenal agents on the duodenal mucosa and blood vessel. It causes low expression of Epidermal Growth Factor Receptor (EGFR), Epidermal Growth Factor (EGF), Heat Shock Protein (HSP) 70, Occludin, Nitric Oxide Synthase (NOS), in the gastric mucosa, in extremely cold temperature than those in extremely hot temperature, increasing the gastric acid secretion in extremely cold temperature than in extremely hot temperature. Therefore, this review aims to give general insight into the role of low temperature in peptic ulcer development and further consideration in the treatment of peptic ulcer diseases
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Using the protection motivation theory to examine the effects of fear arousal on the practice of social distancing during the COVID-19 outbreak in rural areas
The commentary elucidates the importance of Protection Motivation Theory (PMT) as a theoretical framework to encourage the practice of social distancing in rural areas as the world grappled with the pandemic of COVID-19 outbreak
Experimental dataset investigating the effect of temperature in the presence or absence of catalysts on the pyrolysis of plantain and yam peels for bio-oil production
More than 1.3 billion tons, a third of the total food pro- duced, is wasted annually, and it has been predicted to in- crease in the coming years. Food waste significantly con- tributes to greenhouse gas (GHG) emissions resulting in the release of about 3.3 billion tonnes of CO 2 into the environ- ment yearly. Hence this large amount of wastes, with ad- verse environmental effects, needs to be appropriately man- aged. New technologies such as Anaerobic digestion, fermen- tation, and gasification are being used to produce renewable energy, which in turn reduces the increasing level of food wastes in the environment. Pyrolysis of biomass materials or food wastes produces high-value energy products or bio-oil that can possibly replace non-renewable fossil fuels when it is upgraded. In this study, pyrolysis (thermal treatment in the absence of oxygen) of plantain and yam peels to produce bio-oil, was in- vestigated. The pyrolysis conditions, wide temperature ranges at an interval of 100 °C (200â700 °C), absence of a cata- lyst (AOC), the use of zeolite âY catalyst using two sepa- rate heterogeneous catalysis procedures were imposed and used to produced bio-oil. In the first procedure, the pyrolysis gases were allowed to rise through a zeolite-Y catalyst bed (HTC). And in the second procedure, the plantain or yam peel feedstock was first mixed uniformly with the zeolite-Y cata- lyst before pyrolysis (HMC). The GCâMS machine was used to analyze or characterize the obtained bio-oil while prox- imate analysis and XRF machine were used to characterize the plantain and yam peels feed. The residue, biochar, from the pyrolysis process, was also characterized using the XRF machine
Moringa oleifera as natural coagulant in water treatment and production of antifungal soap
The use of Moringa oleifera seed in water purification has reduced the use of
chemical-based coagulants which is detrimental to both human and livestock. This project
aimed at testing the microbial properties of M. oleifera seed oil extract on some selected
pathogens (Bacterial and fungi). The oil was extracted using Soxhlet apparatus with ethanol as
solvents. Gas-chromatography-mass spectrometry (GCMS) analyses were carried out for the
identification of active components in the oil extract. The zone of inhibition test carried out
showed that this particular plant seed oil extract has antifungal property with Candida albicans
and Rizopus stolonifera with highest zone of inhibition. The raffinate was used for water
purification and the oil for the production of an antifungal soap
Classification and characterization of bio-oil obtained from catalytic and non-catalytic pyrolysis of desludging sewage sample
Sewage sludge is a very harmful waste when improperly discharged into the environment
because of its inherent abundant pathogens, organic pollutants, and heavy metal constituents. The
pyrolysis of sewage sludge is viewed not only to reduce pollutants associated with it but also one of
the viable alternative sources for renewable energy or biofuel production. In this study, the effect of
catalyst and temperature on the yield and composition of bio-oil obtained from the catalytic and
non-catalytic pyrolysis of desludging sewage samples (DSS) was investigated. Modified pyrolysis
reactor was used to pyrolyze the DSS at temperature ranges of 300â400, 400â500, 500â600
and 600â700 â with and without the use of zeolite-Y catalyst. The âheterogeneousâ catalysis
reaction yielded 20.9 wt% bio-oil, while the reaction without catalyst yielded 18.2 wt% bio-oil.
Pyrolysis of the DSS favored char yield of between 55.4 and 76.6 wt%. The X-ray
Fluorescence (XRF) analysis showed high silica (46 and 56.1 wt%), calcium (20.9 and 15.50 wt%),
and low organic matter (12 and 12.87 wt%) contents present in the desludging feedstock before and
after pyrolysis respectively. The gas chromatographyâmass spectrometry (GCMS) analysis indicated
the presence of nitrogen-containing compounds (between 20 and 50 wt%), mono-aromatics (18
and 28 wt%) and oxygenated compounds, in the form of carboxylic acids, aliphatics, ketones, ethers,
esters and aldehydes in the bio-oils. Pyrolysis process development is, therefore, essential to clean
the environment of pollutants from sewage sludge, by its conversion to more useful chemicals. In contrast, sewage sludge with high silica content may be tailored to the production of building
materials
Computational Method for Global Sensitivity Analysis of Reactor Neutronic Parameters
The variance-based global sensitivity analysis technique is robust, has a wide range of applicability, and provides accurate sensitivity information for most models. However, it requires input variables to be statistically independent. A modification to this technique that allows one to deal with input variables that are blockwise correlated and normally distributed is presented. The focus of this study is the application of the modified global sensitivity analysis technique to calculations of reactor parameters that are dependent on groupwise neutron cross-sections. The main effort in this work is in establishing a method for a practical numerical calculation of the global sensitivity indices. The implementation of the method involves the calculation of multidimensional integrals, which can be prohibitively expensive to compute. Numerical techniques specifically suited to the evaluation of multidimensional integrals, namely, Monte Carlo and sparse grids methods, are used, and their efficiency is compared. The method is illustrated and tested on a two-group cross-section dependent problem. In all the cases considered, the results obtained with sparse grids achieved much better accuracy while using a significantly smaller number of samples. This aspect is addressed in a ministudy, and a preliminary explanation of the results obtained is given
Computational Method for Global Sensitivity Analysis of Reactor Neutronic Parameters
The variance-based global sensitivity analysis technique is robust, has a wide range of applicability, and provides accurate sensitivity information for most models. However, it requires input variables to be statistically independent. A modification to this technique that allows one to deal with input variables that are blockwise correlated and normally distributed is presented. The focus of this study is the application of the modified global sensitivity analysis technique to calculations of reactor parameters that are dependent on groupwise neutron cross-sections. The main effort in this work is in establishing a method for a practical numerical calculation of the global sensitivity indices. The implementation of the method involves the calculation of multidimensional integrals, which can be prohibitively expensive to compute. Numerical techniques specifically suited to the evaluation of multidimensional integrals, namely, Monte Carlo and sparse grids methods, are used, and their efficiency is compared. The method is illustrated and tested on a two-group cross-section dependent problem. In all the cases considered, the results obtained with sparse grids achieved much better accuracy while using a significantly smaller number of samples. This aspect is addressed in a ministudy, and a preliminary explanation of the results obtained is given