PERFORMANCE EVALUATION OF ENERGY-SAVING BULBS IN SELECTED NIGERIAN LOCATIONS WITH ARTIFICIAL NEURAL NETWORK MODELLING

The performance evaluation of energy-saving bulbs in the Nigerian market is crucial in assisting energy auditing, which is beneficial to producers and consumers of electricity. Specifically, the high-power bills issued monthly by Electricity Distribution Company in most parts of Nigeria have made Nigerians in our various domestic homes embrace the latest lighting technology that consumes less energy.In this study, lighting system data were obtained from twenty-four households from different geographical zones in Nigeria. The performance evaluation of compact fluorescent light(CFL) bulbs was investigated and the observation was predicted with artificial neural networks (ANN) to enhance informed policy formulation and decision-makingResults showed that CFL bulbs givehigh-quality light that is cost-effective and environmentally friendly. ANN predicted the observation with high accuracie

MODELLING AND OPTIMIZATION OF COEFFICIENT OF PERFORMANCE OF LOWER TEMPERATURE CYCLE OF TWO-STEP REFRIGERATION SYSTEMS

The coefficient of performance (COP) of a single-stage refrigeration system is low, thus there is a need for two-step refrigeration systems when there is a desire to have an evaporator temperature that is below -25 oC. The COP of the lower temperature cycle of the two-step refrigeration systems is a function of the COP of the refrigeration systems.This research aimed at optimizing COP of the lower temperature cycle of two-step refrigeration systems using eco-friendly refrigerants.Thermodynamic analysis of these refrigeration systems was performed by varying seven operating parameters. R-134a was used in the high-temperature cycle (HTC) and R-23 was used in the low-temperature cycle (LTC). The coefficient of performance of the lower temperature cycle (COP.REF[LTC]) of the refrigeration systems was optimized using Half Factorial Design of Design-Expert 12.0.1. The influence of the condensing temperature (TC,HTC),evaporating temperature (TE,HTC), cascade temperature difference (∆TCAS,DIFF), evaporating temperature (TE,LTC), superheating temperature (TSUP,LTC), sub-cooling temperature (TSUB,LTC), and refrigerant mass Flow rate (ṁHTC)was investigated on the values of COP.REF[LTC] of the refrigeration systems. The highest value of COP.REF[LTC] (18.1) was obtained under optimum conditions of the 30 TC,HTCoC , -40 TE,HTCoC, 0 ∆TCAS,DIFFoC, -50 TE,LTCoC, 0 TSUP,LTCoC, 20 TSUB,LTCoC and 0.01 ṁHTC kg/s.The study revealed that all the factors having interaction with TC[HTC] and TE[HTC] have a great influence on the value of COP.REF[LTC

SENSITIVITY ANALYSIS OF HYBRIDIZED WIND/PV ENERGY SYSTEM FOR POWERING TELECOMMUNICATION MAST IN LAGOS SOUTH-WEST NIGERIA

Power delivery micro-grid of hybridized wind and solar system installations keep growing worldwide. There is a great economic advantage in the use of cleaner renewable energy for power generation in the telecommunication industries, especially in remote areas. This studyanalyses the effect of three wind speed fluctuationsor levels on a hybridizedwind energy system’s electricity production for a typical three (3) BTS telecommunication mast using Hybrid Optimization Model for Energy Resources (HOMER)PRO software in Lagos south-western Nigeria as a case study. The economic implication of energy at the different wind speed levels investigated was also derived. From the obtained results, a wind speed of 4, 4.22, and 5 m/s gave an annual electric production of 39,950, 39,050, and 39,250 kWh and energy cost of 195, 192, and ₦175, respectively. This result is useful for the techno-economic operation of hybridized wind/solar system powered by three (3) BTS telecommunication masts

ANTIPLASMODIAL POTENTIAL OF Garcinia kola (HECKEL) STEMBARK EXTRACT IN ALBINO MICE

Garcinia kola stem bark forms part of recipes used traditionally for the treatment of malaria. In view of the prevalence of malaria in Nigeria, this study investigated the phytochemical, mineral and proximate components, as well as antiplasmodial activity and toxicological effect of Garcinia kola stem bark extract against Plasmodium berghei infected mice. The plant sample was screened for phytochemical, mineral and proximate components using standard laboratory techniques. Thirty five mice were divided into seven groups of five mice each. Malaria was induced in all the groups intraperitoneally with 0.2 mL of infected blood containing about 107 of P. berghei parasitized red blood cells, except group 6 (extract only) and group 7 (normal control). Group 1 received 100 mg/kg bodyweight of the extract orally. Group 2 received 200 mg/kg of the extract. Group 3 received 300 mg/kg of the extract. Group 4 received 5 mg/kg of chloroquine. Group 5 (induced but untreated control). The haematology, liver function enzymes and histopathology of the liver were carried out using standard protocols.  The plant was rich in alkaloids, iron and fibre. The extract treated groups (1-3) showed significant decrease (p≤0.05) in parasitemia level after seven days of treatment. There was no significant difference in AST, ALT, ALP, bilirubin and GGT activities in all the extract treated groups compared to the control. No pathological changes were evident in histopathology of all the groups treated with various concentration of the extract. The result obtained from this study confirmed the antiplasmodial activity of methanol extract of G. kola stem bark. The highest inhibition of P. berghie parasite was observed at dose 300 mg/kg comparable to chloroquine, with no hepatoxicity which confirmed the safety of G. kola. The phytochemicals and nutritional components could be responsible for the observed antiplasmodial activity of the plant.   &nbsp

AMELIORATION OF ARSENIC-INDUCED TOXICITY BY ETHANOL LEAF EXTRACT OF PHYLLANTUS AMARUS LINN AND VITAMIN C IN MALE ALBINO RATS

The ameliorative effect of ethanol leaf extract of Phyllantus amarus (EEPA) and vitamin C in arsenic-induced toxicity was studied. Thirty-six (36) male albino rats divided into six groups of six (6) rats each were used for the study. Arsenic toxicity was induced in three of the groups by daily intake of 100 ppm of arsenic as Dimethylarsenate (DMA) in their drinking water.  Two of the arsenic-exposed groups were treated with 200 and 500 mg/kg bwt of EEPA and vitamin C respectively. The third group was not treated during arsenic exposure. The fourth and fifth groups were positive control for P. amarus and Vitamin C respectively, while another group served as the normal control. All treatments were done orally for six weeks. The effects of treatments on lipid profile, lipid peroxidation and liver function were thereafter studied. Increased levels of total cholesterol, LDL-cholesterol and malondialdehyde (MDA) were observed in plasma and lymphocytes of untreated arsenic-exposed rats compared to the control group. Arsenic increased total cholesterol and LDL-cholesterol concentrations, while triacylglycerol concentration was reduced significantly. Treatments with EEPA and Vitamin C however ameliorated the dyslipidemia observed in arsenic-exposed groups. Exposure to DMA increased plasma activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) of the animals, while plasma activity of ALT in rats treated with Vitamin C was not different compared to the control. Both treatments however, had no significant effect (p > 0.05) on the activity of plasma AST. P. amarus may therefore play a role in ameliorating arsenic-induced dyslipidemia in male albino rats.     &nbsp

Students’ Perception of Reference Services as Determinant of Library use in Colleges of Agriculture in Oyo State, Nigeria

Descriptive survey design was used to study the students’ perception of reference services as determinant of library use in the Colleges of Agriculture in Oyo State (Federal College of Agriculture, Moor Plantation, Apata, Ibadan [FCAIB] and Oyo State College of Agriculture and Technology, Igboora [OYSCATECH]). The study has four objectives, three research questions and one research hypothesis was tested at 0.05 level of significance. Purposive stratified proportionate random sampling technique and a sampling fraction of fifteen percent (15%) were used to select a sample size of two hundred and eighty-seven (287) students out of the one thousand eight hundred and eighty-five (1885) students in the eight (8) departments that are common to the two Colleges (Population of the study). The response from a well-structured questionnaire administered on the sampled population was analyzed using Statistical Package for Social Science (SPSS). The result of the analyzed data showed positive perception of reference services in OYSCATECH (WX=2.71) and FCAIB (WX= 2.44). The result showed positive correlation between the perception of reference services and use of library in the two colleges of Agriculture in Oyo State –FCAIB ( r = 0.311) and OYSCATECH (r = 0.214). The study also identified purposes and frequencies of using the library by the students in the two institutions. The study recommended the use of electronic reference services in order to enhance ease, visibility, relevance and efficiency of reference services in our libraries and more importantly to encourage use of library

TIME-COURSE EFFECTS OF LOW-LEVELS ARSENIC ON ELECTROLYTES AND LIPIDS IN MALE ALBINO RATS

his study was conducted to investigate the time-course effects of low levels of organic arsenic on electrolytes balance and lipid profiles in different organs of male rats. Animals were exposed to arsenic (As) as Dimethylarsenate (DMA) in their drinking water for 5, 10 and 15 weeks at doses 20 and 40 ppm. Lipids (Triacylglycerol (TAG), total cholesterol, phospholipids) and electrolytes (sodium, potassium, magnesium, calcium) levels were determined in the hepatic, renal, brain and cardiac tissues of experimental animals. Potassium significantly (p<0.05) increased in the hepatic, renal and cardiac tissues after 5 weeks exposure to 40 ppm arsenic. Significant (p<0.05) increase observed in hepatocytes calcium level was shown to be dose-dependent. While there was no observed significant (p>0.05) difference in hepatic and renal magnesium after 15 weeks exposure, magnesium significantly altered in the brain and cardiac tissues after 15 weeks. TAG concentration in most of the organs studied was significantly (p<0.05) altered after 5 weeks exposure to 20 ppm arsenic. Phospholipids in the renal and hepatic tissues were also significantly (p<0.05) decreased after 15 weeks of exposure to As. However, only in the renal tissues was hypocholesterolemia observed in 40 ppm groups at 5, 10 and 15 weeks of exposure. Our findings indicate exposure to progressively low-levels arsenic can result in electrolytes imbalance and dyslipidemia in different organs in rats.     &nbsp

Control and prevention of biodeteriation caused by termites (Isoptera

The paper reviewed the control measures against damage caused by termites. The objective was achieved using baseline published literature and data. This is particularly important because of the ever present destructive effect and presence of termites in every area of life worldwide. Multiple effective measures, ranging from chemical treatments to independent pest management procedures were identified. The right choice and application of termite preventive and control measures will be a great reprieve to stakeholders all over the world.Keywords: Damage, Control, Termites

The Role of Necropsy in Diagnostic Dilemmas as Seen in a Tertiary Hospital in North Central Nigeria

Background. Necropsy (autopsy) has helped medical science and law. It has given rise to numerous diagnostic surprises as it explains cause of death, pathogenesis of diseases, and circumstances of death. It also explains reasons for most therapeutic failures. In spite of its usefulness, the rate has dropped worldwide and Africa is worse hit. This work aims to highlight the role autopsy (Necropsy) plays in demystifying diagnostic dilemmas and to encourage its patronage by medical practitioners, law enforcement agents and society. Methods. This is a retrospective review of autopsy and clinical reports of cases seen by pathologists and physicians in the Jos University Teaching Hospital (JUTH), Jos, North central Nigeria. Results. A total 166 cases were studied out of which 52 had same diagnosis for both attending physician and pathologist, 106 had different diagnoses and in eight cases diagnoses remained unknown even after autopsy was performed. Conclusions. Autopsy remains an important tool for obtaining definitive diagnosis, determining cause of death to explain pathogenesis of diseases, medical auditing and a vital source of data for health statistics and planning