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Synthesis and Property Evaluations of a Bio-Based Anticorrosive Urethane Composites Containing Bisphenol a as Extender
No full textThis article reports the synthesis of an eco-friendly polyurethane
composite system, which was successfully prepared in a onepot
synthetic pathway by combining castor seed oil (CSO),
bisphenol A (BPA), isophorone diisocyanate (IPDI), and functional
hybrid nanoparticles (prepared by modifying the peripheral
surface of silica with 3-aminopropyltrimethoxysilane
(APTMS). The urethane composites were cast as thin films on tin
foils and mild steel and cured under atmospheric moisture.
Attenuated total reflectance Fourier transform infrared (ATRFTIR)
spectroscopy was used to characterise the cured composite
films, scanning electron microscopy (SEM), energy dispersive
X-ray (EDX), X-ray diffraction (XRD), thermogravimetric
analysis (TGA), corrosion resistance, antimicrobial analysis, salt
spray test, and water contact angle measurements. Our
evaluations showed improved thermal and hydrophobic properties
of the composite coatings. Also, the electrochemical and
antimicrobial analyses clearly show resistance to corrosion and
test organisms as the percentage composition of APTMS-SiO2
increases in the urethane system
EFFICACY OF BRIEF COGNITIVE BEHAVIOUR THERAPY AND PSYCHOEDUCATION ON PSYCHOLOGICAL DISTRESS AMONG ADOLESCENTS IN OYO-EAST, OYO STATE, NIGERIA
Get PDFPsychological distress refers to a state of emotional suffering or discomfort, typically marked by symptoms of depression and stress, with anxiety being the most prevalent mental health problem commonly experienced by adolescents. Despite these symptoms and their associated negative outcomes, such as suicide, adult mental disorders, health loss, and disability, there is a paucity of evidence-based psychological treatments, especially in low-income countries with high rates of adolescent psychological distress. Previous studies have focused on cognitive-behavioural therapy and treated psychoeducation as an adjunct treatment. This study investigated the prevalence of psychological distress and examined the efficacy of brief cognitive-behavioural therapy and psychoeducation as mono-therapy in reducing psychological distress symptoms among adolescents. Adopting a survey design and the pre-test post-test control group experimental design, data were obtained from four secondary schools in the Oyo-East Local Government Area by administering a study questionnaire comprising age, gender, family type, parents' marital status, school class, perceived social support, and the Depression, Anxiety, and Stress Scale (DASS-21). A total of 465 participants—238 males (51.2%) and 227 females (48.8%) with a mean age of 13.28 (SD = 1.89)—were involved in the study's first phase. Using the ballot technique, 72 participants were randomly assigned to two experimental groups (A, B) and a control group (C) with 24 participants per group. Given the psychological distress mean score of 30.62 (SD = 21.3) and above as the cut-off point, 6 participants from each of the four schools were matched in each of the study groups in the second phase of the study. A prevalence rate of 51.61% was revealed among the participants using DASS-21 as a measure of psychological distress symptoms. Utilizing SPSSv23, the study found that age, female gender, polygamous family type, parents' marital status (divorced), school class, and perceived social support significantly contributed to psychological distress among adolescents {R = 0.273, R² = 0.075, F(6, 456) = 6.13, p < 0.05}. The study further revealed that after participants in experimental group B received psychoeducation treatment for six weeks, there was a significant reduction in psychological distress symptoms (t(22) = 8.77, p < 0.05). Also, after a six-week exposure period, brief cognitive-behavioural therapy treatment was found to be significantly effective in reducing psychological distress symptoms (t (20) = 6.94, p < 0.05). Additionally, psychoeducation and brief cognitive-behavioural therapy were both equally effective after exposing psychologically distressed participants to the same number of treatment sessions. After a one-month follow-up period, the treatment effects of psychoeducation and brief cognitive-behavioural therapy were maintained with an effect size of 0.24 (r = 0.60). Findings from this study revealed an obvious increase in the number of adolescents suffering from psychological distress. Adopting psychoeducation as mono-therapy and brief cognitive-behaviour therapy in schools would reduce distress prevalence and prevent further vulnerability among adolescents. Schools may endeavour to incorporate psychoeducation and brief cognitive-behavioural skills into the curriculum. Further studies may require investigating prevalence among non-rural resident adolescents and considering a longer follow-up period to ascertain the efficacy of psychoeducation treatment
MUTATION PROFILING OF RBCL AND MATK GENES AND PHYLOGENETIC RELATIONSHIPS OF SELECTED MEMBERS OF THE FABACEAE FAMILY
Get PDFGene mutation profiling involves detecting the type and effect of mutation on a gene. The rbcL and matK genes are chloroplast genes involved in photosynthesis; mutations on these genes can be deleterious or beneficial to the plant. Integrating underutilized legumes into genetic studies alongside major legumes using barcoding methodologies is essential for their genetic improvement. This research aimed to provide detailed mutation information on the rbcL and matK genes of the selected legumes and gain insight into their classification based on DNA barcodes. The sequences of sixteen legumes were used in the study. Five amino acid sequence entries from these species, reference sequences and complete chloroplast genomes were retrieved from the National Center for Biotechnology Information database. The gene sequences were aligned with their reference sequences using MULTALIN to identify amino acid substitutions in the genes. The type and effect of these mutations on protein function and stability were predicted using the SIFT, PROVEAN, and I-MUTANT v.2.0 online servers. The rbcL and MatK genes of Macrotyloma geocarpum were isolated, amplified, and sequenced. Consensus sequences of the sequence entries from 15 species were generated and aligned with those sequenced using the Muscle algorithm. Phylogenetic analysis was conducted using the neighbor-joining algorithm in MEGA 11 software. Results revealed 32 and 22 amino acid substitutions in the matK and rbcL genes, respectively. Five substitutions in the matK gene across three species were predicted to be deleterious by all three predictive software, and one substitution in the rbcL gene was predicted to be beneficial. The double barcodes (matK+rbcL) and single barcode (rbcL) classified the selected legumes randomly, however, matK gene classified the legumes down to the genus and species levels. It also revealed that Cajanus cajan, an underutilized legume, is the closest to Vigna unguiculata, implying the possibility of genetically improving C. cajan using the V. unguiculata genome. The matK gene also gave similar result to that of chloroplast genome. Consequently, matK gene is recommended as a core barcode sequence in the Fabaceae family
Facial Anthropometry-Based Masked Face Recognition System
Get PDFDifferent kinds of occlusion have proven to disrupt the accuracy of face recognition
systems, one of them being masks. The problem of masked faces has become even more
apparent with the widespread of the COVID-19 virus, with most people wearing masks in
public. This brings up the issue of existing face recognition systems been able to accurately
recognize people even when part of their face and the major identifiers (such as the nose
and mouth) are covered by a facemask. In addition, most of the databases that have been
curated in different organizations, countries are majorly of non-masked faces, and masked
databases are rarely stored or universally accepted compared with conventional face
datasets. Therefore, this paper aim at the development of a Masked Face Recognition
System using facial anthropometrics technique (FAT). FAT is the science of calculating the
measurements, proportion and dimension of human face and their features. A dataset of
faces with individual wearing medical face mask was curated. Using the Facial
anthropometry based technique a Masked Face Recognition System developed. This system
was implemented using Local Binary Patterns Histogram algorithms for recognition. On
testing the developed system trained with unmasked dataset, show a high recognition
performance of 94% and 96.8% for masked and non-masked face recognition respectively
because of the Facial anthropometry based technique adapted. On deployment, users were
been recognized when they are wearing a mask with part of their face covered in real-time
Design and Performance Evaluation of a Cassava Harvester Lifting Unit
Get PDFThe research study employed the method of lifting to design a cassava lifting unit and its
performance was evaluated using the power-take-off (PTO) of the tractor at 540 rpm speed and
transmitted via the reduction gearbox of ratio 19:1 then to the driving mechanism (chain and
sprocket) which drives the lifting discs to perform the third stage of harvesting cassava. The field test
was conducted at the Federal University of Technology, Akure Ondo State. Nigeria teaching and
research farm with one variety of cassava (sweet cassava). The tests were conducted at 1m interval
spacing to evaluate the effect of different levels of parameters on the performance of the implement.
Forward speed, depth of cut, and soil moisture content (clayey-loam soil) were the parameters that
varied. The harvester was operated at forward speeds of 2.0 km/h, 4.0 km/h, and 6.0 km/h, depth of
cut 30 cm, 32 cm, 34 cm, and soil moisture content of 15 %, 17.5 %, and 20.15 % (wet basis) using
a moisture meter. The parameters kept constant were, soil type, variety of cassava, and lifting
speed. The field capacity or harvesting rate which is the area harvested per unit time was also
measured. The lifting efficiency is high at an optimum moisture content of 20 % wet basis. The
optimum forward speed and depth of cut for an efficient lifting of the cassava was 4 km/h and 34 cm
at 60 % moisture content and soil penetration resistance was taken on the first day twice (morning
and evening) at different depths. The final reading was taken three days after which rain had fallen.
The increase in lifting efficiency and percentage of tubers harvested was 75% at optimum forward
speed and soil moisture. Thus, the result showed that there is an improvement in the harvesting
approach and method
A comprehensive review of biofuel utilization for household cooking in developing countries: Economic and environmental impacts
Get PDFThe global energy consumption for household cooking is substantial, comprising
approximately 90 % of total household energy usage worldwide. Research indicates that
in 2002, food-related energy consumption averaged 340 million BTU (approximately
359 million J) per person. With the current global population exceeding 7 billion, this
translates to an estimated annual energy consumption for cooking of 2.380×1018 BTU
(2.519 ×1021 J). A significant portion of this energy is derived from the combustion of
firewood, contributing to deforestation, CO2 emissions, and the release of toxic gases,
which in turn, exacerbates environmental pollution and poses health risks. Household
cooking, heating, and lighting activities in developing countries account for about 58 %
of the black carbon emissions globally. Recognizing clean cooking as a crucial solution
to mitigate climate change, there is growing interest in utilizing biomass as a source for
biofuels and bioenergy. The comparative diminishing in greenhouse gas emissions from
renewable fuels compared to conventional fossil fuels, along with the sustainable nature
of these technological advancements, has spurred increased research into biofuel
technology. To address energy poverty, achieve the Sustainable Development Goals,
and align with the goals of the Paris Agreement, comprehensive and expedited efforts
are needed to expand and enhance access to clean cooking solutions. Consequently,
this article explores the potential of biofuels as viable alternatives to conventional fossil
fuels for household cooking, focusing on their economic and environmental implications
Optimization of the Product Yields of the Pyrolysis of Palm Kernel Shell in a Fixed-Bed Reactor Using Response Surface Methodology (RSM)
Get PDFPyrolysis is a method used for the thermo-chemical conversion of biomass and agro wastes into three major by-products namely, biochar, bio-oil, and biogas in the absence of oxygen. Global waste generation is increasing at an alarming rate. Palm kernel shell (PKS) is among the palm wastes accumulating in many palm oil mills around the globe with the attendant problems in waste management. The utilization of coal for energy generation is more expensive and not environmentally friendly. Bio-oil refineries and industries require the utilization of minimum resources (input) to achieve optimal response (output) in the production process. However, more than 30% of the energy content derivation from the pyrolysis process is wasted due to non-optimization of the process parameters. This study investigated the optimization of the product yields of the pyrolysis of PKS in a fixed-bed batch reactor using response surface methodology (RSM). Masses of 1 kg, 2 kg, and 3 kg were pyrolyzed in batches at process temperature variations of 200 OC, 300 OC, 400 OC, and 500 OC. Design Expert 12 software (Version 12.0.3.0 Stat-Ease Inc. MN, USA) and Analysis of Variance (ANOVA) were used for the statistical analysis. Lack-of-fit, adjusted, and predicted multiple correlation coefficients and coefficient of variation of the different polynomial models were compared to select the best-fitting polynomial model. The optimal feedstock parameters were 2.66 kg of PKS and 410.0 OC process temperature. The predicted results were 0.986 kg of biochar, 1.205 kg of bio-oil, 0.481 kg of biogas, 1116.5 cm3 of bio-oil, and 140.6 minutes. The experimental results were 0.894 kg of biochar, 1.316 kg of bio-oil, 0.498 kg of biogas, 1208.9 cm3 of bio-oil, and at 162.8 minutes through validation. The validated quadratic model was suitable for the optimization and RSM is a numerical, statistical, and mathematical tool for modeling and optimization of the pyrolysis process in a fixed-bed batch reactor
Investigation of Path Loss in a Complex Building Environment Using USRP and GNU Ration
Get PDFThis paper presents the description,
measurements, and analysis of an investigation into the path
loss channel characteristics of a complex building
environment using the College of Engineering building of Afe
Babalola University, Ado-Ekiti, Nigeria as a case study. The
study is conducted on the first floor of the building, which is
compartmentalized into five scenarios. The measurements
are performed in the distinctive line-of-sight and non-line-ofsight
paths. Over 90% of the measurements taken are in the
non-line-of-sight environment of the complex building. The
wideband sliding correlator channel sounder measurement
technique of 1.2 GHz centre frequency was performed using
the National Instrument Universal Software Radio
Peripheral (NI USRP) 2920/GNU (GNU’s Not Unix) radio
testbed. Key statistical considerations associated with path
loss are calculated and the path loss equation model for the
non-line-of-sight and line-of-sight of the entire first floor of
the complex building is obtained. The results of the
investigation show that an increase in path loss is a function
of distance. The calculated path loss exponents were used to
rate the performance of the wireless communication channel.
The values obtained were found to be in tandem with the
existing path loss metrics. Also, the radio propagation along
the enclosed passages and indoor environments experienced
low path loss, while the radio propagation along the
ornamental trees encountered large path loss. Consequently,
the results of the linear regression model and the log-normal
model equation of Nonline of Sight (NLOS) and Line of Sight
(LOS) results are somehow correlated. These results are
useful in predicting the path loss of the radio signal at any
specific distance from the transmitter to the receiver in any
environment similar to the one under investigation. Also, as
a planning and coverage optimization tool for wireless
communication designers
Bridging the Artificial Intelligence Knowledge and Skill Gaps in Africa: a Case of the 3rd Google Tensorflow Bootcamp and FEDGEN Mini-Workshop
Get PDFIn transiting from one civilization to another, technology has played a vital and positive role.
In the 21 st century, one of the digital developments that is paving ways for human life
improvement is machine-assisted technology using Artificial Intelligence (AI). Artificial
Intelligence has successfully enhanced man’s capacity in solving complex problems and
processes. However, as developed nations continue to reap from the adoption of AI in
various fields of human endeavors, the continent of Africa has remained behind, especially
in AI-based skills and research. Various governments in developing nations have
encouraged the adoption of AI, especially in institutions of learning. However, theoretical
adoption without practical experience has remained an ineffective way of bridging the digital
divide. In this paper we present the outcome of a practical approach to bridging the AI
divide among students and researchers in Africa through funding support from the Google
TensorFlow College Outreach Award. A 3-day hybrid bootcamp was organized (11 th to 13 th December, 2023) using the Google funding in order to equip postgraduate students
and researchers with AI and collaborative research skills. A pre-survey method was
employed to ascertain the knowledge level of the bootcamp participants. From the presurveyed
feedback, training sessions on various AI domains were presented, and
participant equipped with practical AI skills using a deployed AI-based cloud programming
platform running on the private Federated Genomic Cloud (FEDGEN) infrastructure at
Covenant University. A post-survey feedback was used to ascertain the effectiveness of this
approach. A comparative analysis of the pre-survey and post-survey reveals a 70%
improvement of AI skills among participants. This shows that having continuous training
session for students and researchers is an effective method in closing the AI skills gap
between developed and developing nations
Energy minimization in temperature control of a milk pasteurization plant using an extremum seeking optimization approach
Get PDFA milk pasteurization plant is a dynamic, nonlinear system that is highly energyintensive
in unstable temperature conditions. It is important to ensure that an
optimum temperature is maintained at the minimum energy cost during the
pasteurization process—even in the face of disturbances which adversely affect the
operation of the plant. Therefore, this paper presents an extremum seeking (ES)
optimization approach for tuning a controller with proportional , integral ,and
derivative (PID) terms so as to optimize the temperature stability of a milk
pasteurization plant. The general mass and energy balance principle was used to
model the plant, and an objective function was developed to reduce the rate at which
liquefied petroleum gas (LPG) was used at the boiler's feeding rate within the 72–
76°C range. The mathematical model of each operational unit as well as the PID
controller tuning for the optimal temperature control was simulated in MATLAB/
Simulink. Standard performance indicators were used to assess the stability
performance of the pasteurized milk temperature control. In comparison to previous
convectional controllers that produced lower output performances, the findings
demonstrated that the ES-tuned PID controller gave the rise time of 0.103 s, settling
time of 14.97 s, peak time of 14.97 s, and percentage overshoot of-0.034 %.
Similarly, the LPG consumption rate of 1.80 × 10−3 kg/s at the boiler in terms of
energy consumption, annual energy T saving and carbon emission reduction were
reduced to 1.16 × 10−3 and 1.25 × 10−3 kg/s, 4.13 × 105 and 4.23 × 105 Baht/year, 89 ×
10−4 and 92 × 10−4 metric ton,respectively, indicating the effectiveness of the ES-PID
controller compared to the conventional controller as investigated. Therefore, as this
research offers a better means of ensuring ideal temperature control throughout the
pasteurization process of milk, it finds good application in the diary industry