Southwestern Nigeria Research Articles

Exploring Stakeholders’ Perspectives on the Barriers to the Application of Cost-Reduction Techniques in Public Higher Educational Building Delivery

The assessment of barriers to the application of cost-reduction techniques in delivering educational buildings in Nigeria is essential in addressing the infrastructural shortage, building performance, delay, cost, time overrun, and abandonment in the delivery of higher educational buildings (HEBs). This study examines barriers to applying cost-reduction techniques in educational buildings in southwestern Nigeria. Using a survey design, the questionnaire was distributed to stakeholders who participated in delivering the government intervention, private donors, and internally generated revenue educational buildings in public tertiary institutions in southwestern Nigeria from 2012 to 2022. A total of 150 copies of the questionnaire were administered, while 133 responses were obtained and analyzed. To begin with, data reliability and validity were examined using Bartlett’s sphericity, Cronbach’s alpha, and Kaiser–Meyer–Olkin (KMO) tests, accordingly, followed by descriptive, Kruskal–Wallis H test, and exploratory factor analysis. The six components obtained from exploratory factor analysis for explaining the barriers to applying cost-reduction techniques in educational buildings were as follows: ambiguity in HEB contracts awards and project executions, lack of control from the HEIs management over HEB project delivery, perceived political influence in HEB procurement, unrealistic contract requirements and change orders, non-prioritization of automation integration in HEB delivery, and deficiencies in contract documents and costing. This study recommends establishing a project-monitoring team involving independent consultants from project inception to reduce excessive errors, practices of assigning contracts to the lowest bidder, and excessive claims for variation orders that escalate the project’s final sum.

Pattern of admissions and needs assessment for palliative care services among in-patients in a tertiary health facility in South-Western Nigeria

BackgroundPalliative care evolution focuses on education and medication accessibility. As little as 12% of palliative care needs are met. Assessment of the domains of Palliative care and patients’ and families’ experience are essential in life-limiting conditions. The Lagos University Teaching Hospital (LUTH), have the National Cancer Centre without offering palliative care services.AimThe aim was to examine pattern of admissions and needs assessment for palliative services among patients admitted into LUTH wards.Materials and methodResponses were entered into a data sheet inputted into Epi info version 7.2. Descriptive characteristics of the participants were presented as frequencies and percentages for age, sex, pattern of disease, domains of Palliative care, Advance care Plan, Preparation for home care, death and Education about the illness and category of medical conditions (palliative and non-palliative conditions). Together for Short Lives (TfSL) tool was used to categorize respondents’ conditions into Palliative and Non-palliative conditions. Chi-square test was used to determine association between independent variables (pattern of diagnoses, stage of disease, advanced care plan, preparation for home care/ death and education on illness) and dependent variables (category of medical condition). Chi-square test was also used to explore the association between specialty of the managing doctor (independent variable) and Advance care plan (dependent variable). The level of statistical significance was P-value < 0.05.Results80.6% of the respondents had palliative care conditions, 83.7% had family members as their caregiver while 13.2% of the participants had no caregiver and 65.9% had no advance care plan. There was no preparation for home care or death in 72.1%, 70.5% had education about their illness, and 68.2% were in the advanced stage of their disease. Participants attending the surgery non-trauma unit (51.6%) were more likely to have advance care plans. Adults were more likely to have palliative care conditions (79.8%) compared to children (20.2%), and was statistically significant.ConclusionMajority of the participants need palliative care services but are unavailable and unmet and the most predominant condition was cancer. Majority had no advance care plan or preparation for home care or death despite having advanced stage of the disease. This survey emphasized the need for symptom management, communication and provision of support.

Epidemiology of geriatric orthopaedic injuries in a tertiary hospital in southwestern Nigeria

Life expectancy in sub-Saharan Africa (SSA) has increased owing to economic growth and improvements in medical care. An increased representation of older people among orthopaedic trauma victims is a significant consequence of population ageing, as shown in previous studies, including few in SSA. This retrospective review in Nigeria aims to corroborate previous studies and highlight the emergence of geriatric orthopaedic trauma (GOT) as a public health concern in SSA. Among 241 orthopaedic trauma in-patients aged ≥ 60, the mortality rate was 3.7%. They made up 21.2% of adult orthopaedic trauma admissions. The incidence of GOT increased steadily over the five-year study period with a spike during COVID-19 lockdown. Males constituted 51%. Mean age was 72.5 years (range, 60–105 years). Mean distance to the hospital was 35.8 km and 50.6% lived farther than 10 km. The main causes of injury were falls (50.6%) and traffic crashes (48.1%). Fractures were the predominant (91.7%) injuries. Univariate analyses revealed significant differences along age and gender stratifications. Longer distance to the hospital significantly delayed presentation. The study supports previous studies and shows that GOT is evolving as a public health concern in SSA. The 2030 Sustainable Development agenda is apt to stem the trend.

Study of the seasonal characteristics of rainfall rate in Southwestern Nigeria and its effect on induced attenuation in earth-satellite communications

Tropospheric propagation channel modeling is gaining more attention in the scientific community, especially in the applications of the upcoming high-frequency satellite communication systems. Channel modeling is essential to predict link performance, for example, in the area of Bit-Error-Ratio (BER) in a single-user scenario and in a multi-user scenario, especially in the areas of throughput and latency. This study investigates the seasonal characteristics of rainfall rate and rain-induced attenuation in terms of exceedance and worst-month rain statistics over selected tropical locations in Nigeria. The coefficient of variation (CV) of rain rate has also been analyzed to examine the variability of rainfall rate due to the inhomogeneity nature of the chosen region. The GPM satellite 30-min rain rate data has been used for rain attenuation prediction through a 30-min to 1-min metric conversion model. Validation of rain attenuation was conducted through a two-year (2013–2014) beacon measurement of rain attenuation at 12.275 GHz at the Akure site. The ITU-R 618–13 (2017) rain attenuation model has been modified based on the rain attenuation beacon measurement. The modified ITU-R model has produced a least root mean square error (RMSE) of 6.4 when compared to the ITU-R model with 23.5 RMSE. The attenuation difference reduces as the frequency difference moves to the upper frequency bands. The ITU-R model overestimates the calculations from the GPM-derived results, which indicates the modification of the ITU-R model for the tropical location. Spatial variation of attenuation at 30 GHz revealed intensive and dry seasons exhibited the highest and lowest attenuation induced values, respectively. The results can be applied to power-enhanced satellite systems to achieve good signal availability in the study areas.

Infrastructures of epidemic response: Mpox and everyday repair work in southwestern Nigeria

Mpox (formerly known as monkeypox) was declared a Public Health Emergency of International Concern (PHEIC) by the World Health Organization on 23rd July 2022, however cases of the disease have been detected in Nigeria since the 1970s and more recently since it began spreading in more urban areas of the country from 2017 onward. Nigeria has a strong track record of epidemic preparedness and response, spearheaded by the Nigeria Centre for Disease Control. Despite being somewhat separate architectures on paper, epidemic response (in particular, integrated disease surveillance and response) relies on a foundation of primary health care, which is inadequately funded not only in Nigeria, but globally. Situating mpox response within this wider landscape, we draw on ethnographic research from September 2022–March 2023 in southwestern Nigeria on lived experiences of mpox and mpox response, focusing on the perspectives of frontline health workers and community-based suspected or confirmed mpox cases. We aimed to understand how prioritization and resource constraints shape mpox response at a local level, including effects on the everyday work of frontline health workers in public health and clinical care who are left to “make do.” We analyze their experiences interfacing with two intersecting infrastructures, community-based surveillance and primary health care. Health workers’ improvisation and “repair work,” which we detail, enables the surveillance system to function in some capacity. However, health workers must regularly contend with competing priorities and routine care that may be sidelined during an outbreak or epidemic. We argue that this reveals the limitations of a global health security agenda as it materializes at a local level and the need for strengthening primary health care for longer-term sustainability.

REE signatures in quaternary deposits: implication for provenance and economic potentials

The Rare Earth Element (REE) geochemistry of siliciclastic sediment in the Ilaje area, eastern Dahomey basin, southwestern Nigeria was conducted to determine the provenance, geotectonic setting as well the REE economic potential in the sediments. Geochemical analysis results (ppm) revealed the concentration of La varies from 1.87–21.47 while Ce ranges from 1.16–45.98. Others include; Pr (1.07–39.56), Nd (0.71–26.02), Sm (0.42–12.51), Eu (0.20–4.66), Gd (0.27–8.79), Tb (0.29–3.97), Dy (0.28–3.62), Ho (0.22–2.76), Er (0.29–2.64), Tm (0.33–3.83), Yb (0.37–3.75) and Lu (0.29–3.03) respectively while the ∑REE ranges from 2.25 to 6686.75 ppm. The REE normalization plot is characterized by an inclined shape depletion indicating depletion trend. The patterns show an enriched Light Rare Earth Elements (LREE) and Heavy Rare Earth Element (HREE) pattern indicating upper continental crust sourced materials. The plot also revealed a negative Eu anomaly which may be associated with plagioclase fractionation in the acidic source rocks. The high ∑REE in the sediments has uncovered the economic potential of the sediments as a useful raw material resource for technological advancement.

Evaluation of heavy hydrocarbon liquid in the Eastern Dahomey Basin, Southwestern Nigeria (case study of Agbabu Bitumen in Ondo State)

Solvent-aided dilution processes are often employed to recover bitumen by reducing its viscosity. In this study, methanol, toluene, and xylene were investigated as potential hydrocarbon solvents for solvent-aided hydrocarbon recovery of Agbabu bitumen. To achieve this, the solubility of the sample in the solvents was determined with a solubility test, its viscosity was measured with the Saybolt Furol Viscometer using the ASTM D88 method, and its SARA analysis was conducted using high-performance liquid chromatography. Agbabu bitumen was found to have a high content of saturates and aromatics. Viscosity decreases as pressure increases, while solubility reduces as temperature increases. The sample was most soluble in toluene, and its viscosity was reduced most in it, followed by xylene. Methanol reduced the saturates content and significantly raised the asphaltene content, keeping the mixture viscosity high. In terms of asphaltene stability of the mixtures, the bitumen-methanol system with the lowest colloidal instability index of 0.874 will give a mild asphaltene deposit issues compared with others that are unstable. This approach of combining multiple tests with the CII can accurately predict the behavior of Agbabu bitumen in solvents and enhance decision on the choice of bitumen recovery technology.

Determination of heavy metal concentration in African pike (Hepsetus odoe) from Alape River, Southwestern Nigeria

Aquatic ecosystems in Nigeria face significant environmental challenges because of anthropogenic activities, resulting in heavy metal contamination. Fish body weight and length and heavy metal concentrations in African pike (Hepsetus odoe) from Alape River, Igbokoda, Ilaje Local Government Area of Ondo State, Southwestern Nigeria, were investigated. Copper (Cu), Cadmium (Cd), Iron (Fe), Manganese (Mn), Nickel (Ni), and Lead (Pb) concentrations were measured in the gills, intestines, and trunks of the fish over six months (i.e., from May 2022 to October 2022) using an atomic absorption spectrophotometer (Buck Scientific’s 210VGP). Significant variations in heavy metal concentrations were observed across different months and organs. The order of concentrations for the six months, from highest to lowest, was Fe (2.26 mg/kg) > Ni (0.37 mg/kg) > Cu (0.23 mg/kg) > Mn (0.27 mg/kg) > Pb (0.05 mg/kg) > Cd (0.01 mg/kg). Higher concentrations were generally observed in the gills and intestines in May and June, whereas elevated levels were observed in the gills in September and October. These concentrations were compared with the maximum permissible limits established by the Food and Agriculture Organization and the World Health Organization for fish consumption, and all measured heavy metal concentrations were determined to be below the permissible limits. Body weight ranged from 172 to 362 g, and length ranged from 15.7 cm to 23.5 cm. The regression coefficient (b) ranged from − 0.134 to 0.204, indicating a relatively weak length–weight relationship. The condition factor (K) exhibited variations in the overall health and well-being of the fish. Based on these findings, the consumption of African pike from the Alape River is currently considered safe for humans, regardless of fish size, with all of the heavy metal concentrations within the permissible limits. However, continuous monitoring is crucial to ensure the ongoing safety of aquatic ecosystems and human health.

Prescription patterns and therapeutic gaps among persons with epilepsy in Southwestern Nigeria.

Introduction: Pharmacotherapy with antiseizure medications (ASMs) has been a cornerstone for achieving long-term remissions in persons with epilepsy (PWEs). This study aims to determine the prescription patterns and treatment gaps (TGs) among PWEs. Methods: Accordingly, a descriptive cross-sectional study was conducted with 940 PWEs aged ≥18years having clinically confirmed diagnosis of epilepsy based on the International League Against Epilepsy (ILAE) criteria. At a scheduled interview with each participant, a previously established questionnaire was used to obtain clinical information relating to epilepsy in terms of the age of onset, etiology, duration of epilepsy, frequency, types, and number of ASMs used. Results: There were fewer male participants [445 (47.4%) vs. 495 (53.6%)] than females, with a higher mean age of onset [(35.19 ± 21.10 vs. 31.58 ± 20.82years; p = 0.009]. The medication characteristics showed that 336 (35.7%) of the 940 PWEs recruited were not on any ASMs, whereas the remaining 604 (64.3%) patients were on ASMs, with 504 (83.4%) on monotherapy vs. 100 (16.6%) on polytherapy. The PWEs on ASM monotherapy had a higher mean age [40.92 ± 19.40 vs. 33.61 ± 16.51years; p < 0.001] and higher mean age of onset [34.47 ± 21.80 vs. 25.39 ± 19.78years; p < 0.001] than those on polytherapy. Furthermore, there were more persons on ASM monotherapy among the participants with seizure duration < 2years [251 (87.5%) vs. 36 (12.5%)] and seizure duration > 2years [253 (79.8%) vs 64 (20.2%)]. Conclusion: The majority of the participants receiving ASMs were on monotherapy, with carbamazepine being the most frequently prescribed medication. Furthermore, about a third of the participants had TGs; therefore, healthcare providers should focus on alleviating the TGs among PWEs.

ANALYZİNG SEATED AND STANDİNG POSTURES WİTH ANTHROPOMETRİC MODELİNG FOR ERGONOMİC DESİGN

The design of workstations and workplaces for ergonomics can be challenging when determining anthropometric parameters such as standing height. This study aimed to develop model equations for determining standing height (SH) using regression analysis as an alternative to measurement. The study involved 406 healthy young adults (206 male and 200 female) aged between 19 and 27years from Abeokuta south western Nigeria. Seated-at-shoulder level (SSL), seated-at-knee level (SKL), popliteal height (PH) and standing height (SH) measurements were taken for each participant. Multivariate regression analyses was used to determine the SH with correlation coefficient (R), coefficient of determination (R2) and Standard error of estimation (S.E.E) calculated. Study results showed a strong correlation (P

Geophysical and geoenvironmental engineering assessment of contaminated workstation soils in a metamorphic environment

This study aims to employ the electrical method, multi-pollution indices, and statistical optimization to establish a common ground for the utilization of contaminated soil as construction material and for agricultural purposes. Two samples each were taken at a depth of 0.5 m and 1.0 m from the eatery, auto-mechanic, car wash, and transformer workstations and at a control site in Akungba-Akoko, southwestern Nigeria. The concentrations of the following geochemical parameters were analyzed: Cr, Pb, Zn, Cd, Mn, and Cu. The resistivity distribution of the workstations’ subsurface layers was determined using Schlumberger vertical electrical sounding (VES). The generated geoelectrical sections revealed four geoelectric layers (topsoil, weathered layer, partially weathered/fracture bedrock, and bedrock) with two curve types: HA (50%) and AA (50%) across the workstations. The topsoil resistivity values (65–184 Ωm) from the VES results suggest moderately rich organic matter and averagely very fine-grained sand. The concentrations of the heavy metals in all the soil samples are within the maximum allowable concentration as stipulated by the National Environmental Standards and Regulations Enforcement Agency in the soil and are suitable for farm activities. Similarly, the geotechnical tests of the Atterberg limit, grain size analysis, compaction, and CBR revealed that all the soil samples met the criteria of a good pavement design but with poor landfill material. Pearson's correlation coefficient revealed that a strong relationship between Igeo\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${I}_{geo}$$\\end{document}-PLI, Igeo\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${I}_{geo}$$\\end{document}-RI, PLI-RI, TSR-Fines, MDD-CBR, LL-MDD, and LL-CBR exists among the multi-pollution indices, the geotechnical properties of soil, and the resistivity distribution of the topsoil. This suggests similar levels of heavy metal pollution and a common source of anthropogenic activities throughout the four workshops and provides the link between geotechnical properties and resistivity distribution for future soil management strategies. The exposure of children and adults to multiple heavy metals through inhalation at the four workstations shows no significant non-cancer or cancer risks.

Groundwater Quality Assessment: A Case of Urban Population Demography and Nutrient Enrichment in Ibadan, Southwestern Nigeria

Groundwater Quality Assessment: A Case of Urban Population Demography and Nutrient Enrichment in Ibadan, Southwestern Nigeria

Assessment of the Nutritional and Ethno-medicinal Uses, Domestication, Production and Conservation of Senecio biafrae Among Farmers in Ekiti State, Southwestern Nigeria

Assessment of the Nutritional and Ethno-medicinal Uses, Domestication, Production and Conservation of Senecio biafrae Among Farmers in Ekiti State, Southwestern Nigeria

Investigating the competency of some selected soft computing techniques for modeling of lateritic soil strength based on index properties

This study aims to assess the capability of some soft computing techniques including ANN, M5P and RF to accurately predict the strength of selected lateritic soils in southwestern Nigeria from index properties including specific gravity, linear shrinkage, liquid limit, plasticity index, fine sand content, and fines content. To achieve this goal, the experimental dataset obtained from the laboratory analysis of three hundred soil samples taken from thirty different lateritic deposits within southwestern Nigeria was divided into model and gaging dataset. The model dataset contains two hundred and forty data points, which were divided into 70% for training and 15% each for testing and validation of the proposed models. The gaging dataset contains sixty data points, which were used to validate the proposed models against prominent existing models in the literature. The models performances were evaluated using various statistical estimators. Based on the statistical estimators, the proposed models outperformed the existing models in the literature and provided satisfactory performances, thus, they are validated. The obtained R2 values using the ANN model are 0.9967, 0.9963, 0.9989, and 0.9852 for training, testing, validation, and gaging dataset, respectively; the R2 values obtained for M5P model are 0.6676, 0.5501, 0.636 and 0.6727; and the R2 values for RF model are 0.8346, 0.6380, 0.7564, and 0.7901. This implies that ANN provided the most reliable model for the prediction of the soil strength. Thus, ANN is strongly recommended for prediction of lateritic soil strength.

Analysis of differential item functioning in agricultural science examination across southwestern nigeria's senior schools

Differential Item Functioning poses a threat to test fairness and validity in educational assessments. To this end, this study probes the incidence of DIF in the Senior School Certificate Agricultural Science Examination (SSCASE) across school locations in Southwestern Nigeria. It determined the magnitude of DIF using item parameters in SSCASE. The study applies one, two and three-parameter logistic models to analyze the dichotomous data responses of 818 randomly selected students from urban and rural locations. The ex-post facto design adopted the 2015 National Examination Council SSCE in Agricultural Science as its instrument (α =0.887) in this study. The study population comprised SSCE candidates from Osun, Ondo, and Oyo. The results showed the magnitude of DIF in SSCASE was large and moderate (1PLM=0.52 significant DIF, 2PLM=0.45 moderate DIF, 3PLM=0.47 moderate DIF) across school locations. The study concluded that 1, 2 and 3 PLMs can produce fair items in SSCASE.

Knowledge and practice of essential nutrition actions among pregnant women in Ibadan, South-western Nigeria

Background: Maternal nutrition during the first 1,000 days has important influences on children’s nutrition and pregnancy outcomes. This study therefore assessed the knowledge, attitude and practice of essential nutrition actions among pregnant women utilizing antenatal care services in Ibadan municipality, South-western Nigeria. Methods: A descriptive cross-sectional study was conducted among pregnant women (15-49 years) receiving antenatal care (ANC) services across selected private and public health facilities. A semi-structured questionnaire was used to collect data on optimal dietary intake, prevention and control of anaemia and promotion of supportive lifestyle and care, according to the essential nutrition actions framework. Results: The mean age of respondents was 29.85±4.89 years while the mean gestational age of pregnancy at respondents’ ANC booking was 18.33±6.12 weeks. About one-third (33.60%) of the respondents had poor knowledge scores (mean knowledge score 5.70±1.50 out of 10), with no significant difference across type of health facility. Mean attitude score was 13.76±2.44 out of 20, while practice was generally poor (mean practice score 4.80±1.34 out of 10). Respondents attending larger tertiary hospitals for ANC had higher knowledge and practice compared to those who attended smaller primary health care centers/mission homes. Additionally, the time of booking, parity, and type of antenatal care center were statistically significant to knowledge and practice (p&lt;0.05). Conclusions: Antenatal care is still a valid platform for delivering maternal knowledge and encouraging practice of essential nutritional actions. It is recommended that expertise in tertiary hospitals be diffused to lower cadre of health care facilities to further strengthen ANC service delivery.

Application of Electrical Resistivity Sounding in delineation of the Aquifer Transmissivity and Basement Structure at Igarra, Southwestern Nigeria

Information on the aquifer transmissivity and basement structure of Igarra, southwestern Nigeria, is scarce. Thus, this study aimed to apply electrical resistivity sounding and drilled borehole information to determine the underlying bedrock structure (basement structure) and the aquifer transmissivity of Igarra. Twenty vertical electrical soundings (VES) were carried out along 4 established E-W traverses intending to intercept the fracture systems. The resistivity data acquired were curved matched, and iterated using Schlumberger O' Neil software to obtain layer parameters. The layer parameters were evaluated to obtain the Dar-`Zarrouk parameters, which were used to determine the aquifer transmissivity. The resistivity-sounding result revealed four to six geoelectric layers that comprised topsoil, lateritic soil, weathered basement, fractured basement, partially fractured basement and fresh basement. The VES result revealed an undulating basement, with depths varying from 20.1 m to 53.8 m, suggesting evidence of fracturing and faulting within the basement. Correlation of the VES data and borehole log revealed that the weathered and the fractured basement constitute the aquifers, found between 2.4 – 53.8 m depths, and aquifer thickness ranged from 0.7 – 44.3 m. Analysis of the VES result showed an average computed transmissivity value of 18.48 m2/day. These values indicate that the basement is undulating with adequate groundwater-yielding materials (aquifer), capable of promoting adequate recharge potentials from precipitation.

Knowledge, attitude, and practice of substance abuse among adolescent in south-west Nigeria

Aim: Gaining understanding of the knowledge, perception, and practice of substance abuse among Adolescent in southwest Nigeria. Study Design: A non-experimental research design was used for the study, and a total of 133 respondents were selected from cross sectional administered questionnaire in selected secondary schools in Owo Metropolis, Ondo State, Nigeria. The study was carried out at Achievers University Owo, Southwestern Nigeria. Methodology: Questionnaire from the respondents was used, was simple comprising of logically and easily understandable questions relating to the topic and answering the research question. The questionnaire was made to measure what it is supposed to measure as accurately and consistently as possible. The statical results of the descriptive data were obtained using the Statical Package for Social Sciences (SPSS version 20) and relevant descriptive and inferential statistical method was employed. Results: The results revealed a total of 133 students from four different schools in Ile-East Local Government area in Ondo State, Nigeria. The demographic data showed that there were more males among these schools representing 60.2% of the entire sample size. Majority of the sample size also showed between 15 and 16 years old representing 47.4% and 21.8% respectively. 91.7% of them had received information about substance abuse, most of them from their peers (49.6%) and school (27.8%). 78.2% of the respondents indicated, that they had never used psychoactive substance before, majority gave several reasons such as it is a bad for their health which took most reason (38.3%), other reasons include fear of the repercussions (11.3%), and other gave no reason (17.35). Minority of them admitted having used psychoactive substances at a time (21.8%) and 125 of this minority agree that they used it occasionally, when it is available and at parties. 34.6% of the respondents had a family members that abuses drugs or other psychoactive substances, most of them were relatives (15.8%) and their fathers (12.8%), which shows influence family members and relatives have on substance abuse. Conclusion: The adolescents were analyzed to have fair knowledge of substance abuse, its effect as well as a fair attitude towards it.

Engineering Evaluation of Laterite Derived from Sedimentary Rock for Use as Subgrade and Sub-Base Materials

Geotechnical assessment of lateritic soils obtained from along the Ojota and Shagamu ends of the Lagos–Ibadan expressway was conducted to evaluate their suitability for use as sub-grade and sub-base materials. Laboratory tests, including moisture content, specific gravity, particle size distribution, fabric/plasticity, compaction, and California Bearing Ratio (CBR), were performed on eight (8) soil samples following British Standards (BS) 1377 methods for soil testing. The lateritic soils were classified as clayey sand, silty clay, and silty to clayey sand. They exhibited moderate plasticity and semi-pervious characteristics, suggesting suitability for use as sub-grade materials. Samples 3, 5, 7, and 8 were identified as more suitable for road construction materials, while Samples 1, 2, 4, and 6 showed susceptibility to seasonal volume changes due to high clay content. These samples would require minor soil stabilization to mitigate the effects of their active clay contents. Adequate drainage systems were recommended to prevent water accumulation, soil volume changes, loss of load-bearing capacity, and potential material failure beneath road pavements. The geotechnical properties of the lateritic soils from the tropical area of Ojota–Shagamu differed significantly from those of other lateritic soils found in southwestern Nigeria.

Multi-Year Continuous Observations of Ambient PM2.5 at Six Sites in Akure, Southwestern Nigeria

The spatial–temporal variations of fine particulate matter (PM2.5) in Akure, a city in southwestern Nigeria, are examined based on multi-year continuous observations using low-cost PM2.5 sensors at six different sites. The average annual concentration of PM2.5 across these sites was measured at 41.0 µg/m3, which surpassed both the Nigerian national air quality standard and the World Health Organization air quality guideline level. PM2.5 levels were significantly higher during the dry season (November–March), often exceeding hazardous levels (over 350 µg/m3), than during the wet season. The analyses of trends in air mass trajectories and satellite data on fire occurrences imply that the transport of dust and accumulation of PM2.5 originating from local/regional open burning activities played crucial roles in increased PM2.5 concentrations during the dry season. Further, site-to-site variations in the PM2.5 levels were observed, with relatively high concentrations at less urbanized sites, likely due to high local emissions from solid fuel combustion, waste burning, and unpaved road dust. Diurnal patterns showed morning and evening peaks at less urbanized sites, accounting for an estimated 51–77% of local emissions. These results highlight the importance of local emission sources in driving spatial–temporal PM2.5 variations within the city and the need for targeted mitigation strategies to address the significant air pollution challenges in Akure and similar regional cities in West Africa.