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AFTERMATH OF NAIRA REDESIGN ON THE PERFORMANCE OF MICRO, SMALL AND MEDIUM SCALE ENTERPRISES IN ADO ODO OTA LGA, OGUN STATE
Get PDFThis study examined the aftermath of the Naira redesign on the performance of Micro, Small, and Medium Scale Enterprises (MSMEs) in Ado-Odo Ota Local Government Area, Nigeria. The redesign of the Naira presented economic challenges for micro-businesses, many businesses suffered from depleted capital and financial hardship, and low sales resulted in low income affecting their family and well-being in the long run. This study focused on Ado-Odo LGA which helped in the geographical imbalance in the study of how naira redesign has affected MSMEs.
A descriptive research design was used in this study with the use of a questionnaire in the collection of data from owners of MSMEs in Ado Odo Ota LGA. Data was collected from 314 MSME owners across various communities in Ado-Odo Ota LGA, like Sango, Iju, Atan, and Ota. The Covenant University Research Ethics Committee (CUREC) in Nigeria has awarded ethical authorization, guaranteeing compliance with moral norms.
Micro, Small, and Medium Enterprises (MSMEs) in the Ado-Odo Ota Local Government Area revealed that the Naira redesign initiative had a negative impact on MSMEs, especially those with limited access to electronic payment methods. According to the research, it is recommended that MSMEs prioritize the development of digital literacy in order to maintain competitiveness in the digital age. Furthermore, it strongly advocates for the government to involve MSMEs in the development and implementation of policies.
In conclusion, the naira redesign policy, intended to move towards a cashless economy and enhance the currency's security, inadvertently exacerbated the challenges faced by MSMEs
BREAST TUMOR KINASE EXPRESSION AND ESTRADIOL LEVELS AMONG BREAST CANCER PATIENTS IN LAGOS, NIGERIA
Get PDFCancer is a major factor in global death rates and a significant challenge to improving life expectancy worldwide. Breast cancer (BC), typified by the unregulated growth of abnormal cells within breast tissue, arises from a combination of genetic mutations, environmental factors, hormonal influences, and lifestyle choices. Studies have shown that the presence of Breast tumor kinase (BRK) gene overexpression results in increased BC cell proliferation and enhanced cell migration. Studies have also revealed that the dysregulation of estrogen (a hormone responsible for the proliferation and growth of specific cells in the body, which is also responsible for the development of secondary sexual characteristics in women) modulates some molecular signaling pathways involved in breast tumor growth and progression. This observational study aims to evaluate the expression levels of BRK and estradiol levels in BC patients as a prognostic marker in breast tumorigenesis in Nigerian patients. A total of forty women, 20 BC patients who had been histologically diagnosed, and 20 healthy control participants were recruited for this study after informed consent was obtained. Venous blood samples (5ml) were drawn from the study participants into anticoagulant tubes and transported to the molecular biology laboratory for analysis. Total RNA was extracted using the TRIzol reagent method. RNA concentration, integrity, and purity were analyzed using a NanoDrop spectrophotometer. cDNA synthesis and quantitative analysis of the relative expression levels of BRK were done using a Reverse transcriptase real-time qPCR machine. From the estradiol, 25ul plasma was used for enzyme-linked immunosorbent assay (ELISA) detection of estradiol according to the manufacturer’s instructions. Overall, mean BRK expression levels in BC was significantly higher (1.6 folds higher) than the expression levels of BRK in healthy control (P < 0.05). Mean estradiol level in BC vs healthy control was 330 ± 27.42 and 309 ± 27.41 pg/mL, showing no significant difference in estradiol levels between the 2 groups. For the first time, this study reports BRK expression levels in Nigerian BC and healthy control and identified BRK as a prognostic marker for monitoring BC progression, thereby providing a suitable target for aggressive cancers common in Nigerian population. This study provides deeper insights into genetic contribution to cancer progression and a biomarker guide for treatment modalities
EXPERIMENTAL AND COMPUTATIONAL ASSESSMENT OF Discorea bulbifera DERIVED BIOCHAR AND HYDROCHAR FOR IBUPROFEN RELEASE
Get PDFThe efficacy of ibuprofen in inflammation management depends on efficient delivery to the targeted site. Utilising a delivery agent would involve ibuprofen adsorption and release for improved delivery. This work studies the utilisation of Discorea bulbifera derived biochar and hydrochar for ibuprofen release. The biochar was prepared in a muffle furnace at 300 oC for 90 min and the hydrochar was prepared in a hydrothermal autoclave at 200 oC for an hr. Characterisation of the chars was performed using several techniques such as Brunauer-Emmett-Teller (BET) analysis, Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), electron dispersive X-ray (EDX), and scanning electron microscopy (SEM). The following biochemical assays were carried out; Protein albumin denaturation assay, hypotonic solution induced hemolysis stabilizing assay, Heat induced hemolysis stabilizing assay. Ibuprofen equilibrium adsorption was performed at 180 min adsorption time, using concentrations (5–200 mg L−1). The equilibrium of adsorption was evaluated using the Freundlich, Temkin, and Langmuir isotherm models. Non−linear Freundlich adsorption isotherm gave the best descriptions of ibuprofen adsorptions onto the studied chars. Freundlich adsorption capacities of biochar and hydrochar are 21.977 and 19.921 mg. g−1, respectively. Egg albumin denaturation inhibition anti−inflammatory results show that biochar (≈ 85 %) performed better than hydrochar (≈ 70 %). Similar trend was observed at lower concentrations of the chars for heat induced hemolysis inhibition studies and as concentration increased, the trend changed such that hydrochar (≈ 38 %) performed better than biochar (≈ 17 %). Ibuprofen equilibrium adsorption performed using initial ibuprofen concentrations (5–200 mg L−1) was established in 2 hours, for biochar and hydrochar, and the highest ibuprofen removals occurred at pH 4. Density functional theoretical calculations gave results which are in excellent agreements with adsorption studies. Both biochar and hydrochar showed good performance as long−term adsorbents for the removal of ibuprofen and results from in vitro and computational studies indicate they have great promise for ibuprofen delivery
Evaluation of the engineering properties of asphaltic concrete composite produced from recycled asphalt pavement and polyethylene plastic
Get PDFThis study investigated the suitability of recycled asphalt pavement and polyethylene wastes
as coarse aggregate in asphaltic concrete by evaluating the impact of the use of polyethylene
polymer wastes and recycled asphalt pavement composite as aggregates on the physical
and mechanical properties of the asphaltic concrete. The physical characteristics of the
aggregate and bitumen were determined using relevant parametric tests. Recycled asphalt
pavement was used to make asphaltic concrete samples using LDPE at 5%, 10%, 15%,
RAP at 5% and HDPE at 5%, 10%, 15%, and a mixture of LDPE + HDPE at 5+5%, 7.5
+7.5% and 10+10% RAP at 5% as additives. Marshall Stability test was conducted to
assess the mechanical strength of the asphaltic concrete, and the results included information
on the aggregate’s stability, flow, density, voids filled with bitumen, voids filled with air,
and voids in mineral aggregate. In addition, the surface and crystal structure of the aggregates
was studied by carrying out a microscopic examination with a Scanning Electron
Microscope (SEM) and X-Ray diffraction (XRD). The results obtained from this study demonstrated
that RAP, HDPE & LDPE are viable conventional aggregate substitute for asphalt
concrete production
Thermal Performance of Vapour Compression Refrigeration System using Bimetallic Strontium Hexaluminate Nanorefrigerants
Get PDFNanoparticles are added to standard compressor lubricants to improve performance and reduce the
energy consumption of vapour compression refrigeration systems (VCRS). This work evaluated the compatibility,
viability, and utility of a bimetallic oxide strontium hexaluminate (SrAl12O19) nano-lubricant with nominal sizes of
20–40 nm by characterising and evaluating its thermophysical properties while assessing its effect on the performance
and energy consumption of existing, unmodified VCRS. Eco-friendly R600a were used as the system's refrigerant and
the performance, energy consumption, and energy efficiency of VCRS were investigated by altering the concentration
of SrAl12O19 (1%–20%) in the compressor lubricant. The results showed that as the temperature increases, the
viscosities significantly decreased and increased as the concentration of nanoparticles is increased. In contrast, the
density and acidity of the nanolubricant increased as the volume concentration of nanoparticles increased. The addition
of nanoparticles into the compressor oil enhanced the performance of the VCRS performance and reduced the energy
required to operate the system; however, these performance metrics decreased as the concentration of nanoparticles
increased further. When the concentration of nanoparticles increased, exergy efficiency reached the maximum at 5%
volume concentratio
Particle size distribution analysis of carburized HT250 gray cast iron using ImageJ
Get PDFThe study focused on the particle size analyses of a carburized HT250 gray cast
iron using ImageJ software to understand the pattern of carbon diffusion after
the carburization process. Pulverized pal kernel shell was deployed in
the carburization of several samples of the grey cast iron after which the samples were
characterized using scanning electron microscope (SEM) to study the microstructure of
each sample. More so, ImageJ was equally deployed in the analyses of the SEM
microstructures to understand the diffusion patterns of the carbon from the pulverized
palm kernel shell so as to predict their structural behavior when deployed in fabrication
process. Some of the important features from the ImageJ include Surface Plot,
Interactive 3D surface plot and Intensity thresholding. The result showed the various
diffusion patterns of carbon into the parent material. Thus, this result will help in the field
of material science on the best method of material processing for adequate mechanical
and structural properties
Value Engineering: Index for Cost Reduction in the Manufacturing Environment
Get PDFIn a highly competitive market, manufacturers seek ways to reduce the cost of
manufacturing products to remain in business despite customers' varying demands, ranging
from personalised products to mass production. Value Engineering (VE) explores the
functional balance between a product's cost and performance by utilising alternative
solutions to eliminate waste. This paper aims to assess the current literature in the topic
area to gain insight into how the manufacturing industry can apply VE techniques to reduce
product costs. It is evident from the literature assessment that VE significantly addresses
manufacturing problems through a systematic and structured approach that aims to identify
opportunities for cost reduction, quality improvement, and enhanced functionality while
improving customer satisfaction. The method optimises the performance of products,
processes, and systems. VE principle evaluates manufacturing procedures to optimise
workflow, reduce cycle times, and utilise resources effectively. The approach examines
product designs to make them simpler, more functional, and easier to manufacture. It
locates and fixes flaws, lessens variation, eliminates wasteful practices and surplus
inventory, and enhances overall product performance. Furthermore, it promotes cooperative
problem-solving techniques and the investigation of alternative solutions to resolve
manufacturing bottlenecks. Manufacturers, therefore, can enhance value, efficiency, and
competitiveness by implementing VE principles
Design of a Therapeutic Student Centre in Covenant University, Ota, Nigeria: User-Centred Approach
Get PDFThis qualitative study addresses the pressing
need for a therapeutic and supportive student center at
Covenant University, Nigeria, to tackle escalating mental
health concerns and the absence of dedicated well-being
spaces on campus. Through semi-structured interviews
with 100 undergraduate and postgraduate students, it
gathers comprehensive insights into their needs,
preferences, and perspectives regarding such a center.
Employing a combined inductive-deductive approach to
thematic analysis, grounded in trustworthiness strategies
like prolonged engagement and member checking, key
findings underscore the importance of natural lighting,
private comfortable rooms, counseling services, art
activities, and a welcoming atmosphere. These insights
directly shape recommendations for the center's layout,
furniture, services, and stigma-reduction campaigns. The
study's rigorous methodology, emphasizing
trustworthiness, highlights its contribution to capturing
authentic student voices and translating them into
actionable recommendations. Acknowledging limitations,
such as cultural specificity, it calls for future
cross-cultural studies and architectural expertise
integration. By centering on students’ perspectives, this
research advances discourse on therapeutic architectural
design's mental health impact, offering a model for higher
education institutions to co-create supportive,
user-centered spaces prioritizing holistic well-being
State of charge estimation based on a modified extended Kalman filter
Get PDFThe global transition from fossil-based automobile systems to their electric-driven counterparts has made the use of a storage device inevitable. Owing to its high energy density, lower self-discharge, and higher cycle lifetime the lithium-ion battery is of significant consideration and usage in electric vehicles. Nevertheless, the state of charge (SOC) of the battery, which cannot be measured directly, must be calculated using an estimator. This paper proposes, by means of a modified priori estimate and a compensating proportional gain, an improved extended Kalman filter (IEKF) for the estimation task due to its nonlinear application and adaptiveness to noise. The improvement was achieved by incorporating the residuals of the previous state matrices to the current state predictor and introducing an attenuating factor in the Kalman gain, which was chosen to counteract the effect of the measurement and process noise resulting in better accuracy performance than the conventional SOC curve fitting-based estimation and ampere hour methods. Simulation results show that the standard EKF estimator results in performance with an error bound of 12.9% due to an unstable start, while the modified EKF reduces the maximum error to within 2.05% demonstrating the quality of the estimator
Robust hybrid estimator for the state of charge of a lithium-ion battery
Get PDFThe use of batteries for diverse energy storage applications is increasing, primarily
because of their high energy density, and lithium-ion batteries (LiBs) are of particular
significance in this regard. However, designing estimators that are robust to compute
the state of charge (SOC) of these batteries in the presence of disturbance signals
arising from different battery types remains a challenge. Hence, this paper presents a
hybrid estimator that combines the extended Kalman filter (EKF) and sliding mode
observer (SMO) via a switching function and tracking closed loop to achieve the
qualities of noise cancellation and disturbance rejection. Hybridization was carried
out in such a way that the inactive observer tracks the output of the used observer,
simultaneously feeding back a zero-sum signal to the input gain of the used observer.
The results obtained show that noise filtering is preserved at a convergence time of
.01 s. Also, the state of charge estimation interval improves greatly from a range of [1,
.93] and [.94, .84] obtained from the extended Kalman filter and sliding mode
observer, respectively, to a range of [1, 0], in spite of the added disturbance
signals from a lithium–nickel (INR 18650) battery type