Journals National University of Science and Technology (NUST)
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The Effects of Sub Lethal Levels of Lead on Acetylcholinesterase Activity in the Rock Pigeon, (Columba Livia)
Get PDFLead is one of the most abundant heavy metals that has become widely distributed and mobilised in the environment. It exists in various forms which are bioavailable to many organisms including birds, causing physiological changes upon exposure. The aim of this study was to investigate the effects of sub lethal levels of lead on acetylcholinesterase activity in the Rock pigeon (Columba livia). Twelve free range and two pen reared (control) pigeons were collected from breeders around the city of Bulawayo and placed in separate cages. Six free range and one pen reared birds were exposed to 1.25 ppm lead acetate spiked feed and water for 72 hrs, whilst the remaining birds served as the unexposed control. Spiked feed and water were changed daily. Both the exposed and unexposed birds were sacrificed and the muscle, heart and liver tissues isolated and assayed for acetylcholinesterase activity. There was significant inhibition of enzyme activity in all tissue samples obtained from lead exposed free range birds when compared to their unexposed counterparts. In the lead exposed free range birds, muscle and liver acetylcholinesterase activity was below 0.005 µg/min/mg protein while that of the heart was in the 0.02-0.07 µg/min/mg protein range. Enzyme activity was greater than 0.1 µg/min/mg protein in the unexposed free range birds. Comparing the acetylcholinesterase activity of the lead exposed pen reared control, with that of the lead exposed free range birds, the latter demonstrated significant inhibition (p<0.05). The results therefore highlight the inhibitory effect of sub lethal levels of lead on acetylcholinesterase activity which could also be possibly enhanced by prior exposure to other environmental contaminants.>
Bound State Solutions of the Schrodinger’s Equation with Manning-Rosen plus Yukawa Potential using Pekeris-like Approximation of the Coulomb Term and Parametric Nikoforov-Uvarov
Get PDFThe solutions of the Schrӧdinger equation with Manning-Rosen plus Yukawa potential (MRYP) have been presented using the Pekeris-like approximation of the coulomb term and parametric Nikiforov-Uvarov (NU) method. The bound state energy eigenvalues and the corresponding un-normalized eigen functions are obtained in terms of Jacobi polynomials. Also, Yukawa, Manning-Rosen and coulomb potentials have been recovered from the mixed potential and their eigen values obtained.The Numerical results are computed for some values of n at l=0 with α = 0.01, 0.1, 2 and 5 using python 3.6 programming, and these results could be applied to molecules moving under the influence of MRYP potential as negative energy eigenvalues obtained indicate a bound state system. 
Biosorption of Phenol from Aqueous Solution using Water Melon Rind (Citrullus C. Lanatus)
Get PDFThis study focuses on investigating the effectiveness of water melon rind in phenol removal from aqueous solution. The effects of various parameters (pH, initial phenol concentration, biosorbent dosage and contact time) on phenol adsorption were investigated. The pH of 2, initial phenol concentration of 40 mg/L, biosorbent dosage of 0.6 g and contact time of 6 h also deduced to be the optimum conditions for the adsorption process. The maximum phenol removal under optimized conditions was 85%. The sorption data fitted to the Freundlich isotherm with a regression coefficient of 0.9824. The kinetics was best described by the intraparticle diffusion model and Elovich equation with regression coefficients of 1 and 0.8461 respectively showing that the reaction is chemisorption on a heterogeneous surface and the intraparticle diffusion rate only is the rate determining step. The study revealed that water melon rind have a potential of removing phenol from industrial wastewaters. 
Subsurface and lithological evidences from aeromagnetic data in some parts of the Sokoto Basin, North West Nigeria
Get PDFIn this work, a reconnaissance study is presented to delineate the subsurface and lithological interpretation of the aeromagnetic data.To achieve this goal, several enhancement techniques and filtering processes were carried out on these maps. At first, the totalintensity aeromagnetic map is processed through the application of reduction to the magnetic equator technique. Six aeromagneticdata sheets covering some parts of the Sokoto Basin were used. These maps were digitized on a TMI grid. An analysis of the totalmagnetic field over the area of study was carried out using the aeromagnetic data sets. The following deduction were made: theinterpreted lineaments follow a predominantly EW- and NSW-trending orientation, while other orientations in the survey area includeNW-, ENE- and, more rarely E-trending structures, the existence of several high short wavelength magnetic closures with steepgradients near the geologic boundary is a strong indication that the basin may not be as large as shown by the geologic map. Theresidual magnetic field values were employed to obtain the two-dimensional Fourier transforms from which the radial spectrum wasextracted. The slopes of the graph of spectral energy against frequency of nine sections were obtained and used to estimate the depthvalues. The results suggested that the deeper depth of the study area ranges from 1.99 km – 2.83 km while the shallow depth rangesfrom 0.78 km – 1.25 km in conformity to the delineation of favourable lithological units between cretaceous meta-sediments andEocene boundary. Finally, the study reveals that structural interpretation based on aeromagnetic data is an efficient tool for frontierexploration for hydrocarbon accumulation and/or other mineralization
Social media use and the proliferation of fake news during the COVID-19 pandemic in Botswana: the archives and records management dilemma
Get PDFPurpose- To assess the impact of the proliferation of fake news through social media during COVID-19 pandemic on archives and records management in Botswana.
Design/methodology/approach – This is a conceptual paper which adopts the qualitative research approach. Documentary review on fake news, Coronavirus Disease 2019 (COVID19), archives and records management and social media is used to collect data for the paper.
Findings- The main findings were that even though Batswana appreciate social media platforms as they enable easy access to information, these platforms make them more susceptible to fake news and intolerance. This situation has led Botswana to legislate some laws to try to curb the spread of fake news. The paper also established that the digital era has made it difficult for records professionals to identify and preserve authentic records for evidential purposes. As a result, and particularly due to COVID-19, automation of the records manual processes through the use of modern smart technologies has become inevitable fororganisations in the country. Consequently, there is need for continuous training of the archives and records personnel.
Research limitations/implications- The findings of this paper are limited to the reviewed literature on Botswana and may not be generalised to other situations. Practical implications- Findings of this study could assist archivists and records managers in their professional decisions during the post-truth era. The results points to the importance of the preservation of the authenticity and integrity of records
Guest Editors and Reviewers
Get PDFWe would like to thank the following guest editors and reviewers for SAJCIS Volume 01 (2021)
Customisation in cross-assembler design for the PIC16F872
Get PDFThe paper describes the development of a cross-assembler known as MCASM which enables programming of the PIC16F872 in a language similar in style to that of the Intel ASM51. The work was instigated by the needs of students in the National University of Science and Technology for a cheap and versatile means of assembly for this processor. Customised features of the software are described
A Study of the Reaction of Ribose Bis(Thiosemicarbazonato) Copper(II) and Nitric Oxide
Get PDFThe acid constant of ribose bis(thiosemicarbazone), RibTSC, and the formation constants of ribose bis(thiosemicarbazonato) copper(II), Cu(RibTSC-2H), and Cu(RibTSC-2H)-(NO)ₓ were determined (where x = 1 or 2). The SPEFO version of the LETAGROP was used to determine both constants, and the graphical method was also used for the first constant. The results show that RibTSC has one isosbestic point at 350 nm and a pKₐ value of 11,08, Cu(RibTSC-2H) has a relatively large average formation constant of 6,188*106, and the logarithm of the formation constants of Cu(RibTSC-2H)-(NO)₁ and Cu(RibTSC-2H)-(NO)₂ were found to be 8,68 +- 0,12 and 11,41 +- 0,09, respectively.
The reaction between aqueous Cu(RibTSC-2H) and saturated aqueous nitric oxide, NO, in a pH 7.4 buffered aqueous solution, at 20°C, was studied using UV-visible. The absorbance of Cu(RibTSC-2H) at 468 nm decreases as portions of NO were successively added to 2 ml of 2,5*10⁻⁵ mol/L of this complex. A graph of ε(Cu(RibTSC-2H)) at 468 nm against [NO], at 20°C, reflects that Cu(RibTSC-2H)-(NO)₂ adduct is formed, which does not decompose when temperature is raised to 60°C. The concentration of 2.10⁻³ molL⁻¹ for saturated aqueous nitric oxide at 20°C was used for all calculations
Measuring the Impact of Institutional Repositories in selected Zimbabwean State Universities
Get PDFPurposeThis paper reports on a study that was conducted to investigate the citation impact of institutional repositories (IRs) in selected Zimbabwean state universities using the Scopus cited reference search facility. The study assessed the extent to which archived content is cited by publications indexed in Scopus.
Design/methodology/approachThe Scopus cited references search facility was used to mine for documents citing IR content from 2014 to 2018. Results from Scopus searches were exported into text files then transported to excel workbooks for filtering and analysis. The impact of an IR was analysed from two perspectives; cited and citing documents characteristics including but not limited to the number of publications, document types and country affiliation of citing authors.
FindingsResults show that on average 8.6 documents per year were cited for all IRs combined within the 5 year period selected for the study. The most frequent Scopus indexed document type citing IR content were research articles, constituting over 50% of all citing documents across all IRs selected for the study. The most cited document types in all IRs were thesis and dissertations followed by research articles. The University of Zimbabwe IR was found to be the most influential, with 34 citers affiliated in 12 countries.
Originality/valueThe study demonstrated the feasibility of using the Scopus cited reference searching facility to mine for documents citing IRs. The research puts forward a new measure of research impact which involves analysing the extent to which IR content is cited by documents indexed in a major commercial citation database (Scopus)
Selecting the right Microcontroller Unit
Get PDFSelecting the proper microcontroller unit (MCU) for a given application is one of the critical decisions which control the success or failure of the task. There are numerous criteria to consider when choosing an MCU, or in general the processor technology. This paper is numerating and explaining most of the metrics to consider during the phase of selecting the right MCU. It presents an outline of the thought guiding this decision