Nnamdi Azikiwe University Journals
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CORRELATION BETWEEN GLYCATED HEMOGLOBIN AND LIPID PROFILE STATUS AMONG NEWLY-DIAGNOSED TYPE 2 DIABETICS OF INDIVIDUALS OF THREE ETHNIC GROUPS IN SOKOTO, NIGERIA
No full textBackground: Glycated haemoglobin (HbA1c) has been suggested to be a better predictor for coronary heart disease and strongly associated with atherosclerosis. Changes in lipid profile is linked with severity of diabetes as adjudged by HbA1c. Lipid abnormalities are common in type 2 diabetics, but the pattern may vary between ethnic groups.
Aim: The current study was undertaken to explore the association of HbA1c and serum lipid profile parameters in type 2 diabetics among persons of three ethnic groups in Sokoto.
Methods: The current study was a cross-sectional case-control study. The Cochran formula was used to determine the number of subjects recruited. Demographic and clinical characteristics were obtained from all the participants. HbA1c and lipid profile parameters were determined using standard laboratory tests. Ranges for TC <200mg/dl, TG <150mg/dl, LDL-c <100mg/dl and ranges between 51-60 for females and 41-60 for males for HDL-c were considered dyslipidaemia. All data were presented using mean and standard deviation, while independent samples t-test and one-way analysis of variance (ANOVA) followed by Bonferroni multiple comparison test to evaluate the mean differences between the groups at statistical significance of <0.05.
Results: The mean values for serum HbA1c were slightly higher in diabetic groups (7.58±0.87 for Hausa/Fulani, 7.23±0.58 for Igbo and 7.34±0.67 for Yoruba) compared to their corresponding control groups (5.21±0.56 for Hausa/Fulani, 5.15±0.55 for Igbo and 5.21±0.55 for Yoruba) with p <0.0001. Serum levels of total cholesterol, triglyceride and LDL-c in diabetic group (207.99±89.82, 183.16±60.76 and 101.27±52.19 respectively) were higher than the control group (161.68±27.64, 137.14±24.18 and 90.16±28.14 respectively) p <0.0001; whereas, HDL-c was decreased in diabetics (37.26±12.90) than the control group (46.64±11.15) p <0.005. The HbA1c correlated with increased TC, TG and LDL-c (r = 0.483269, 0.623952 and 0.390193 respectively) p=0.0001 and decreased HDL-c level (r= -0.247900) p=0.0001.
Conclusion: It was concluded that HbA1c is positively correlated to dyslipidaemia. HbA1c may be considered as an indirect predictor for dyslipidaemia. The current study therefore, recommend adequate glycaemic control via serum evaluation of HbA1c among type 2 diabetics irrespective of ethnic background
Durability and Microstructural Performance of Metakaolin-based Geopolymer Concrete under Elevated Temperature Exposure
No full textConcrete materials exposed to harsh environment usually experience changes in the microstructure and physical appearance. Geopolymer concrete specimens of grade 20 N/mm2 was targeted at a mix ratio 1:2:4 for metakaolin, fine and coarse aggregate respectively and the alkaline liquid (NaOH:Na2SiO3) which key start the geopolymerisation process was varied from 1:1 to 1:4. The water content of the Na2SiO3 was found to be 40.80 % with a pH value of 12.8 and oxide value of 3.89.This implies that, the commercial sodium silicate use in this study exhibited acceptable pH and silica modulus for geopolymerization. The XRD pattern of the unheated (MKGPC) sample exhibits the characteristic peaks of conventional metakaolinite functions at Bragg’s angles of 11.44, 12.72, 20.45, 25.28, 27.02, 35.88, 38.83, 55.58 and 62.37°. The peak at 12.72° was due to present of the undisturbed crystalline silica in the analyzed sample. The XRD pattern shows a highly amorphous characterization with no sharp peaks for the heated sample. The SEM micrograph shows some changes in the microstructure as the sample transform from crystalline to amorphous for the heated geopolymer concrete. The sample was inserted in a furnace and the temperature was elevated from100OC to 1400OC at a varying period ranging from 2 to 8 hours in accordance with BS EN 12390-2. The optimum mix ratio of 1:3 gave the highest compressive strength, for 12M concentration of (NaOH), there was no significant changes in the compressive strength of 30 N/mm2 obtained at 200 0C until at a temperature of 5000C after which it continue to drop. However, at lower and higher temperature ranging from 100OC to 400OC and 1000OC to 1400OC respectively, the compressive strength was constant as it shows no significant effect even at hourly increase in elevated temperature ranging from 2hrs to 8 hours. More so, the density loss was constant at lower temperature and decreases as the temperature increases
Enhancing the Corrosion Protection of Mild Steel using Nickel-Voltage-Controlled Electrodeposition
No full textTailoring the electrodeposition parameters to yield high performance coating for corrosion control in mild steel is important for its sustainability as an effective corrosion mitigation measure. Nickel film was electrodeposited on mild steel for corrosion inhibition at varied coating voltages. The influence of the coating voltage on the surface morphology with elemental percentage composition and the corrosion resistance of the coating was examined using scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) and potentiodynamic polarization method respectively. Results obtained showed that the electrodeposited nickel film impacted an impressive corrosion inhibitory property on mild steel when compared to the uncoated samples. The study also indicated that corrosion rate of 0.0074996 mm/yr, 0.0005916mm/yr, and 0.00440 mm/yr where obtained with coating voltage values of 2, 4 and 7Volts respectively. This indicates that the coating voltage has significant effect on the corrosion resistance potential of nickel film. The optimal corrosion resistance performance of the coating material was achieved using coating voltage of 4Volts which yielded corrosion inhibition efficiency of 97.7%. The morphology of the samples deposited using the optimal setting indicated smoother surfaces with minimum corrosion affected areas in contrast to the one coated using extremely low and high voltage values. Thus, an optimal electrodeposition voltage at which nickel-coated mild steel exhibits significantly enhanced corrosion resistance has been identified. More also the correlation between the electrodeposition voltage, microstructural characteristics and the corrosion protective film integrity has been established. Hence, optimizing a single electrochemical parameter-coating voltage, is a cost- effective approach for enhancing the durability and sustainability of mild steel in corrosive environments for industrial application
Comparative analysis of dried dehulled and undehulled african breadfruit (treculia africana) seeds using oven drier
No full textThis study investigated the effect of process variables on the moisture content and thermal properties of oven-dried dehulled (DBF) and undehulled (UBF) African breadfruit seeds. Moisture content was determined using the gravimetric method, and the effects of drying time and temperature were assessed. At 70 °C, with an air speed of 2.5 m/s and 240 minutes of drying, moisture content decreased from 66.7% to 12.53% for DBF and 12.95% for UBF. At 40 °C, the moisture content reduced to 15.7% (DBF) and 24.03% (UBF), while at 70 °C, it further decreased to 0.75% and 2.7% respectively. Proximate analysis and thermal property measurements followed. After drying, the specific heat capacity decreased from 2.2405 kJ/kgK to 1.681 kJ/kgK (DBF) and 1.9108 kJ/kgK (UBF). Thermal conductivity dropped from 0.3047 W/mK to 0.226 W/mK for DBF and 0.27 W/mK for UBF. Thermal diffusivity increased from 2.21×10⁻⁴ m²/s to 2.23×10⁻⁴ m²/s (DBF) and 2.3×10⁻⁴ m²/s (UBF). The results showed that DBF experienced greater changes in moisture content and thermal properties than UBF, which may be attributed to the hull in UBF retaining moisture during drying. This indicated that dehulling enhanced moisture removal and altered the thermal properties more significantly during oven drying of African breadfruit seeds
Assessing the Impact of Land Use Land Cover (LULC) and Climate Change on Groundwater Quality in Awka Agricultural Zone
No full textThis study investigates the combined impacts of land use/land cover (LULC) changes, topographic variability, and climate-induced stressors on groundwater quality in the Awka Agricultural Zone, southeastern Nigeria. Over the past decades, rapid urbanization, agricultural intensification, and climate variability have increasingly degraded groundwater resources in sub-Saharan Africa. To address this, the study integrated physicochemical data, satellite-derived LULC classifications (2017, 2020, 2023 and 2024), and climate records of Awka Agricultural Zone from 2017 to 2024 within a GIS-based framework. Findings reveal that urban expansion and agricultural encroachment significantly reduce infiltration and elevate pollutant loads, while declining rainfall and rising temperatures intensify solute concentrations such as nitrates, TDS, and heavy metals. Statistical analyses show strong correlations between groundwater parameters and environmental variables, confirming the interactive nature of anthropogenic and climatic pressures. This research offers a spatial-temporal approach for identifying contamination hotspots and recharge-limiting zones, providing critical insights for adaptive groundwater governance, spatial planning, and climate resilience in data-scarce agro-ecological regions.
 
Predicting and Optimizing the Impacts of Chipped Rubber Tire (CRT) On Concrete Using Response Surface Methodology
No full textThe recycling of waste tire rubber in concrete can reduce reliance on raw materials, contributing to the economic efficiency and sustainable progress of the construction sector. This study aimed to utilise Chipped Rubber Tire (CRT) as a partial substitute for coarse aggregate in the production of rubberised concrete. Various levels of chipped rubber tire replacement, ranging from 0 % to 20 % in increments of 5 %, were used to replace the volume of coarse aggregate; cubes were produced and cured for periods of 7, 14, and 28 days in fresh water. The findings revealed that the slump of the fresh concrete and water absorption increased as the percentage of CRT content increased. The compressive strength and the density of the concrete containing CRT content decreased as the proportion of CRT content rose. Nonetheless, the compressive strength of the CRT-concrete improved with longer curing periods. The generated models displayed excellent correlation, predictability, and alignment between the predicted and actual values, evidenced by high R2 values and low P values, confirming their suitability for predictions. It was noted that the percentage error between the predicted and actual values for all responses was less than 5 %, suggesting a strong agreement between predicted and actual results under optimal mixing conditions. The optimal composition of 6.42797 % CRT and a curing age of 27.997 % yielded the highest compressive strength of 21.432 MPa, water absorption of 1.9667 % and a density of 2075.67 kg/m3 respectively
Security Assessment of Nigeria’s 330 KV Transmission Grid Using Newton-Raphson Load Flow Method
No full textThis study investigates the security of Nigeria’s 330 KV transmission network through contingency-based analysis using the Newton-Raphson Load Flow (NRLF) method in ETAP. The modeled grid, consisting of 58 buses, 17 generating stations, and 24 major load centers, was subjected to single and double outage scenarios to assess its operational limits under stress conditions. The results, presented mainly through contingency rankings, highlight critical events that cause severe voltage depressions and overloading of key transmission corridors, particularly in the northeastern and north-central regions. These findings underscore the vulnerability of the grid to cascading failures if left unmitigated. The analysis also demonstrates that applying corrective measures such as shunt compensation, circuit reinforcement, and selective load shedding can substantially reduce the number and severity of violations. The study provides data-driven evidence to guide operational planning and policy interventions aimed at improving the resilience of Nigeria’s high-voltage transmission infrastructur
Valorization of Papaya Peel Waste via Calcination and KOH Activation into a High-Performance Heterogeneous Catalyst for Biodiesel Production
No full textThe rising need of the sustainable energy emphasizes biodiesel as a possible alternative to petro-diesel. The proposed study is an implementation of a zero-waste approach by transforming the waste of papaya peel into an effective heterogeneous solid base catalyst to transesterify papaya seed oil. Calcination was used to make the catalyst and activated with KOH. SEM/EDX, XRD, BET, FTIR and TGA measurements of the fibrous biomass proved the successful transformation of the fibrous biomass to a microporous catalyst with a BET surface area of 150.5m2/g, a high thermal stability and rich CaO active sites. The elemental analysis showed that the quantity of carbon decreased by 75.7%, calcium increased by 166.5%, and the basicity enhancer, potassium, was successful. An optimum yield of 93.43% biodiesel was obtained under the following conditions; 12:1 methanol to oil ratio, catalyst loading of 1.0 wt%, reaction time of 2.0 hours, agitation of 400, and temperature of 60oC. The biodiesel complied with ASTM D6751 and EN 14214 requirements on specific gravity (0.8684), cetane index (57.371), and flash point (157oC), but, with a kinematic viscosity (6.843mm2/s), was marginally higer but can be corrected by blending. This shows proper waste valorization to a cost effective production of biodiesel
Optimization of Ethanolic-Soxhlet Extraction of Natural Dye from Almond Leaves using Box-Behnken design approach
No full textThis work reports on optimization of extraction of natural dye from leaves of almond tree using Box-Behnken Design (BBD) to design experimental factors and analyze the results statistically. The natural dye obtained would be aimed to substitute synthetic dyes which are harmful and caused pollution to the environment. The ethanol and soxhlet apparatus were employed to perform the extraction through experimental design obtained from Behnken-Box Design expert. Extraction conditions under which empirical research work was performed are temperature, time and amount of plant material, with aim to optimize amount of dye extract yield and color strength responses. The amount of dye extract obtained was quantitatively determined using gravimetric and uv spectrophotometric analyses. The results of the analysis reveal that temperature, time, square of amount of feed material can influence dye yield and color strength of dye extract. The results further reveal that the yield and color strength of dye extract obtained increased as the extraction conditions increased. The phytochemical analysis performed on the dye extract reveals the existence of flavonoids, tannins, alkaloids, steroids, saponins, phenol and terpenoids in the dye extract. The dye extract can impart medicinal functional properties among others on textiles in view of the presence of these bioactive constituents in the dye extract
Terminalia superba Plantations in Forestry Research Institute of Nigeria, Oyo State, Nigeria
No full textThis study assessed the soil nutrient status of Nauclea diderrichii and Terminalia superba plantations in the Forestry Research Institute of Nigeria, Oyo State, Nigeria, to address the limited knowledge on soil nutrients in monoculture plantations in the region. Soil samples were systematically collected from five points at 50m intervals at two depths (0-15 cm and 15-30 cm). The samples were analysed for particle size distribution, Water Holding Capacity (WHC), pH, nitrogen (TN), Available Phosphorus (AP), Organic Carbon (OC), exchangeable cations (Ca²⁺, Mg²⁺, K⁺, Na⁺), cation exchange capacity (CEC), and micronutrients (Fe³⁺, Cu²⁺, Mn²⁺, Zn²⁺). Nauclea diderrichii exhibited slightly lower pH (6.3) and higher WHC (76.52%) compared to Terminalia superba (pH 6.8, WHC 62.25%). The mean OC, TN, and AP were higher in Terminalia superba (35.25 4.79; 2.95) compared to Nauclea diderrichii (25.24; 2.21; 3.32). The study found a strong correlation between the soil chemical (r = 0.962; p < 0.01) and physical properties (r = 0.989; p < 0.01) under Nauclea diderrichii and Terminalia superba, indicating that both species influence soil nutrient status and structure. For exchangeable cations and CEC, Nauclea diderrichii showed higher values, with Ca²⁺, Mg²⁺, K⁺, Na⁺, and CEC at 3.58; 1.56; 0.51; and 6.3, respectively, compared to Terminalia superba. These findings indicate that Nauclea diderrichii plantations have higher soil nutrient accumulation, suggesting better soil fertility. The study recommends that this species be prioritized in afforestation and reforestation programs in Nigeria to enhance soil fertility and support sustainable forest management