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Effect of Duty Cycle Control on Performance of Sepic DC – DC Buck-Boost Converter under Resistive Load Applications
Get PDF This paper investigates the effect of duty cycle control on the performance of the SEPIC (Single-Ended Primary Inductor Converter) DC–DC buck-boost converter, particularly when subjected to resistive load applications. The SEPIC converter, known for its ability to output a voltage either greater or lesser than the input, finds broad application in power supplies and renewable energy systems. An analysis of how the duty cycle influences key performance metrics—such as output voltage, currents and voltage ripple is presented. Simulation result demonstrate that careful modulation of the duty cycle enables optimization of converter performance, offering valuable insights into how these converters can be tuned to enhance efficiency in resistive load scenarios. The results obtained reveal that the Sepic dc dc converter is capable of delivering a maximum output power approximately 1857W at duty cycle of 80 % with 20 kHz switching frequency. Also, at the same switching frequency, 20 % duty cycle, a minimum output power of approximately 5.34 W was obtained. These insights are valuable for power electronics engineers seeking to optimize SEPIC converters for domestic load applications
USING HERBARIUM RECORDS AND IUCN RED LIST TO UNRAVEL EXTINCTION RISK PATTERN IN GENUS GARCINIA IN NIGERIA
Get PDFTrees of economic importance are many times vulnerable to extinction due to factors such as anthropogenic pressure, ethnobotanical uses, urbanization, climate change and spread of invasive species. Species in genus Garcinia are well known for their ecological and economic importance. In this study, herbarium records from the Forest Research Institute of Nigeria (FRIN) national herbarium were searched to determine the distribution of species of Genus Cola in Nigeria. The herbarium spreadsheet also contain information regarding their habitat type records. This records were used in generating species distribution map and analyze the habitat type. The IUCN (International Union of Conservation of Nature) Red List web platform was used to determine the conservation status and threats to species of Garcinia found in Nigeria. This study revealed that Garcinia is highly distributed in Cross River state in Nigeria than other parts of the country. This study revealed that Garcinia is a threatened genus in Nigeria. Some species of Garcinia has not been evaluated for conservation purpose. This study conclude that Garcinia might be at the verge of complete extinction if there are no conservation interventions for the species. It is recommended that species of Garcinia in Nigeria be regenerated to prevent their extirpation and also a recent local population assessments of all the species in this genus should be encouraged
Effect of Alphaspin® Nanoparticles on the Susceptibility of Tomatoes (Solanum lycopersicum L.) to Southern Blight Caused by Sclerotium Rolfsii in Lafia
Get PDFA study was carried out to investigate the disease responses of Alphaspin nanoparticles-treated tomato (Solanum lycopersicum L.) to Southern blight caused by Sclerotium rolfsii in Lafia, Nasarawa State, Nigeria. Two grams each of seeds belonging to the Syria, Roma Savana, and UC82B tomato varieties were exposed to Alphaspin nanoparticles for 10, 20, 30, 40, and 50 min respectively, and challenged with sclerotia obtained from isolates of S. rolfsii. Growth and disease responses of Alphaspin nanoparticles treated tomato plants to S. rolfsii were assessed 4 weeks after inoculation. UC82B tomato exposed to Alphaspin nanoparticles for 40 min proved to be the most susceptible variety to S. rolfsii, with the mean total leaf yellowing 87.50%, leaf necrosis 81.25%, flower wilt 82.50%, stem necrosis 40.00%, stem rot 35.00%, stem wilt 42.50%, plant wilt 45.00%, plant height 37.40 cm, number of leaves 88.00, stem girth 2.25 cm, number of branches 0.75, and number of flowers 7.75. The differences in growth and disease responses were significant among the different tomato varieties (P<0.05). The study revealed that plants exposed to Alphaspin nanoparticles were more vulnerable to southern blight than the untreated control, hence, studies involving the use of other nano materials such as green synthesized nanoparticles are required to further our understanding of the effect of nanoparticles on tomato resistance to southern blight caused by S. rolfsii
Assessing Groundwater Potential and Suitability for Drinking and Irrigation at Federal University of Lafia, Nasarawa State, Northcentral Nigeria
No full textGroundwater is used in industry, agriculture, and drinking. Quality must be checked regularly. This study assessed Federal University of Lafia groundwater potential for drinking and irrigation. Fifteen groundwater samples were analyze and nine Schlumberger geo-electrical soundings were carried out. The results were compared to Water Quality Index and World Health Organization drinking water standards. IP2WIN software was used to smoothed field data for models, geo-electric layers, and sounding curves. KH, QH, H, and Q curve types were obtained. Sandstone, top soil, and sandy shale exhibit varying resistivities, indicating variation in geology. The area has high aquifer protection capacity and moderate to high water potentials. The physicochemical parameters are within WHO drinking permissible limits, except for nitrate which is above the limit. Which implies contamination. The samples are excellent source of water based on water quality index. The study uses Kelly\u27s ratio, magnesium adsorption ratio, sodium adsorption ratio, and chloro-alkaline indices to determine their suitability for irrigation. All the samples are good for irrigation with the exception of the magnesium adsorption ratio, which indicates that samples 1, 2, 3, 4, 5, 8, 9, 10, 11, 12, 13, and 14 are above 50%, indicating a negative impact on crop yield as the soil becomes more alkaline. Based on the results, the area has high groundwater potentials but poorly good for irrigation. Therefore, isotopic and geothermal analysis of the water samples in the area is necessary, in order to ascertain the exact sources of water in the are
IN VITRO ANTIOXIDANT AND ANTIHYPERGLYCEMIA PROPERTIES OF VERBENONE ENHANCED WITH SELECTED SOLUBILIZING COMPOUNDS
Get PDFThe pharmacological activities of verbenone had been reported in several diseased states. This study evaluated the in vitro antioxidant and antihyperglycemia properties of verbenone through linkage with selected solubilizing compounds. Oral Glucose Tolerance Test (OGTT) was conducted in non-diabetic mice overloaded with 2 g/kg bwt. glucose solution. In vitro α amylase and α glucosidase inhibitory activities were evaluated for verbenone and selected solubilizing compounds. 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2) and hydroxyl (OH) radical scavenging activity were evaluated for verbenone and selected solubilizing compounds using references procedures. In OGTT assay, verbenone, lysine, cyclodextrin and metformin significantly (p<0.05) lowered glucose concentration compared with the control from 30 - 120 minutes. Lysine and verb-lysine (12.5 μg/mL) steadily raised the percentage α amylase inhibitory activity, while at the same concentration significantly (p<0.05) increased amylase activity from 70 to 95%. Acarbose and all concentrations of compound examined (12.5 - 200 μg/mL) significantly (p<0.05) increased the percentage inhibitory activity of α glucosidase. All concentrations of verbenone significantly increased the percentage scavenging activities of DPPH, H2O2 and OH. Lysine, cyclodextrin verb-lysine showed a significantly (p<0.05) high hydroxyl scavenging while verb-cyclodextrin and acarbose displayed a lower hydroxyl scavenging. The results indicated that verbenone and its linked solubilizing compounds exhibited in vitro antihyperglycemic properties in glucose loaded mice, increased inhibitory activities of α amylase and α glucosidase as well as increased in vitro antioxidant scavenging activities
Optimizing Federated Graph Attention Networks for Crop Disease Detection in Low-Resource Agricultural Environments
Get PDFThe growing integration of Artificial Intelligence of Things (AIoT) in agriculture is revolutionizing how crop diseases are detected and managed. While centralized deep learning models have shown promising results in disease detection, their feasibility in low-resource agricultural environments is often limited by high communication overhead and data privacy risks. Federated Learning (FL) offers a decentralized solution to this challenge, though existing FL models struggle to handle heterogeneous data distributions that are common in real-world farm settings. This study introduces FeGAN, a Federated Graph Attention Network framework, optimized to improve wheat disease detection in resource-constrained agricultural systems. FeGAN combines adaptive attention mechanisms with communication-efficient aggregation techniques to enhance classification accuracy while minimizing bandwidth consumption. The model was evaluated using datasets from PlantVillage and PlantPAD Wheat Collections, containing diverse disease samples such as Brown Rust, Fusarium Head Blight, and Powdery Mildew. Experimental results demonstrate that FeGAN achieved 94% classification accuracy, outperforming traditional FL models which averaged 88–93%. Moreover, FeGAN reduced communication costs by 30% compared to baseline FL models while converging 40% faster. The model also demonstrated a 25% reduction in energy consumption, making it a suitable solution for deployment on edge devices in remote agricultural environments. FeGAN\u27s scalability, improved efficiency, and privacy-preserving design offer a viable solution for AI-driven smart farming, ensuring accurate disease detection without compromising resource constraints. This study provides insights for developing sustainable agricultural intelligence systems that address the unique challenges of smallholder farmers and low-resource communities
Nutritional Assessment of Children Living with HIV/AIDS in Selected HAART-Providing Hospitals in Abia State, Nigeria
Get PDFMalnutrition happens when the body lacks enough essential nutrients. Children are more vulnerable than adults and face greater risks of serious health problems from poor nutrition. This study examined nutritional assessment for children living with HIV/AIDS. A descriptive cross-sectional study was conducted among 180 respondents at three HAART-providing hospitals in Abia State, namely Abia State University Teaching Hospital (ABSUTH), Seventh-day Adventist Hospital, and Living World Hospital. The study revealed that most caregivers were aged 30–34 years, with a mean age of 33.7 years, and nearly half of the children were between 5 and 9 years old. While over 80% of caregivers knew the classes of food, only about half identified proper child nutrition, and many were unaware of the link between HIV and malnutrition. Exclusive breastfeeding was practiced by 55%. Children’s diets were predominantly carbohydrate-based due to low income. About 38% had recent diarrhea, and 66% were on ART. Anthropometric results showed most children within normal growth percentiles, likely reflecting ART adherence and moderate caregiver nutrition knowledge. The study concluded that although caregivers showed moderate awareness of nutrition, socioeconomic challenges and limited understanding of the relationship between HIV and malnutrition affect dietary diversity and child health outcomes. Based on the findings, it is recommended that continuous nutrition education be provided for caregivers of HIV-positive children, focusing on balanced diets and the nutritional impact of HIV. Government and NGOs should also support income-generating programs and provide nutritional supplements to improve dietary quality and child well-being
Practices of Pig Farmers and Porcine Salmonella occurrence in Nasarawa State
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Farming practices such as the use of antibiotics, feed and feed additives, housing as well as biosecurity measures are important factors leading to spread and persistence of infectious agents and pathogens in farms, environment and transmission of infectious agents to humans. The aim of this study was to assess pig farmers practices and the occurrence of Porcine Salmonella in Nasarawa State of Nigeria. A total of 637 farmers were assessed across the tree agro-ecological zones of the State comprising of 13 local government areas using structured questionnaires alongside 637 fecal samples collected from pigs to determine the association between management practices, Biosecurity practices and general hygiene vis-a-vis Salmonella occurrence. The fecal samples were subjected to culture and isolation methods as described by ISO 6579: +A1:2007. Data from questionnaire responses were subjected to multivariate logistic regression analysis using Epi info version 7.2 to ascertain the risk factors. The study recorded Porcine Salmonella occurrence and observed gaps in knowledge and best farm practices such as farm sanitation practices, biosecurity measures, unhygienic containment methods, feed and water administration promoting the occurrence of Porcine Salmonella. A coordinated One-Health approached is recommended in order to curtail Salmonella transmission and safeguarding the environment from contamination and the health of pig farmers of Nasarawa State
Effect of Magnesium Oxide-Carbonized Hibiscus Sabdariffa (Zobo) Waste and Magnesium–Zinc Binary Oxide Nanocomposites in Mitigating Cadmium and Bacteria in Contaminated Water.
No full textThe need for active and inexpensive materials in combating menace of bacterial as well as heavy metals is very essential to the longevity of man and protection of his environment against deleterious substances such as bacterial and heavy metals. This research was designed to study the mitigative effect of MgO-carbonized zobo waste nanocomposite (MOCZWNC) and Mg-Zn binary oxide nanocomposite (MgZBONC) on Salmonella typhi – gram negative organism and Staphylococcus aureus – gram positive organism as well as eradication of cadmium ions in contaminated water. MgZBONC and MgOCZWNC was prepared, characterized and their adsorption ability was studied using adsorption isotherm evaluation. The mitigative effect of MgOCZWNC and MgZBONC on bacteria was evaluated using turbidimetric method. The maximum sorption capacity of MgOCZWNC and Mg-ZBONC for cadmium was 188.68mg/g and 192.31mg/g respectively. The average crystallite size of MgOCZWNC and MgZBONC was 28.61nm and 59.42nm respectively. The treated samples brought about a steady decrease in the population of Staphylococcus and Salmonella within 2hrs, after about 2hrs, the samples of staphylococcus and salmonella treated with MgOCZWNC continued to show continuity in its mitigative effect at decreasing the population of the bacteria with time while the staphylococcus and salmonella sample treated with MgZBONC experienced a slightly steady drop in their effectiveness after same Nanocomposite period. The MgZBONC adsorbed cadmium ions more effectively and the MgOCZWNC was more efficient in severely reducing the population of staphylococcus and salmonella in contaminated water
COMPARATIVE ANALYSIS OF GAUSS SEIDEL, CONJUGATE GRADIENT AND SUCCESSIVEOVER RELAXATION FOR THE SOLUTION OF NONSYMETRIC LINEAR EQUATIONS
Get PDFThis study undertakes a comparative analysis of three widely used computational methods namely; Gauss-Seidel, Conjugate Gradient, and Successive Over-Relaxation (SOR) for solving nonsymmetric linear equations. The main goal is to assess the effectiveness, efficiency and convergence rates of these methods when applied to nonsymmetric linear systems, which frequently occurs in scientific and engineering problems. The Gauss-Seidel method, knownfor its iterative simplicity and straightforward implementation, is compared with the Conjugate Gradient method, which is acclaimed for its robustness and efficiency in handling large and sparse systems. The SOR method, an optimized version of Gauss-Seidel, was also evaluated to determine its potentials for accelerating convergence. Through a series of numerical experiments and performance benchmarks, the study reveals that the ConjugateGradient method consistently outperforms the other two methods in terms of convergence, speed and computational efficiency, particularly for large-scale nonsymmetric systems. The Gauss-Seidel and SOR methods, while showing competitive performance for smaller or less complex systems, do not match the efficiency of the Conjugate Gradient method in more demanding scenarios. Based on the results, the Conjugate Gradient method is recommended as the preferred choice for solving large nonsymmetric linear systems due to its superior performance