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Open Access
Biochemical and carcinogenic effects of monosodium glutate and soya bean in wistar rats
(Federal University of Technology, Owerri, 2021-07) Bob Chile-Agada, Adaeze
This study was carried out to investigate the biochemical effects of short, medium and long term administration of monosodium glutamate (MSG) and soya beans in both male and female Wistar rats, using standard methods. LD50 was carried out using rats which led to the choice of 1000, 2000 and 3000 mg/kg b.w for low, medium, and high doses of the samples. A total of 210 (105 males and 105 females) weanly Wistar rats weighing 70 – 78g were divided equally into three groups of 70 rats each representing the various experimental durations (2, 4, and 6 months). Each of these groups containing 70 rats was further divided equally into 14 subgroups, each containing 5 rats. Group 1 and 8 were controls for female and male rats fed normal raw chow and saline. Groups 2-7 (female rats) and 9-14 (male rats) were rats administered low dose (LD), medium dose (MD) and high dose (HD) MSG and soya beans respectively. 6-o-Malonylgenistin (98.47%) and Glycitin (98.11%) were the most abundant oestrogen-like compounds in the dehulled and oil of soya beans. The glucose and insulin levels of both male and female rats were significantly altered by HDs of both MSG and soya beans after 6 months while ALT, ALP and AST levels were significantly elevated after 4 and 6 months following administration of both MSG and soya beans and were more extensive in HD soya bean fed rats. No significant changes (P> 0.05) were observed in the urea levels after 2 and 4 months soya beans respective administration to female and male rats, while HD MSG significantly elevated the creatinine levels of male and female rats after 4 and 6 months administration. Administration of soya beans and MSG for 2 and 4 months had no significant effect (P > 0.05) on the bicarbonate and chloride levels. The HDL levels were significantly reduced while LDL, TC, and TG were significantly (P < 0.05) elevated after 6months HD administration of MSG and soya beans. Soya beans administration produced no significant change in the SOD levels for female rats and catalase levels in male rats after 2 months administration whereas the MD and HD administration of MSG significantly elevated MDA levels of both male and female rats after 4 and 6 months. Two and four months administration of soya beans and MSG produced no significant changes (P > 0.05) in the LH and FSH of female rats while MD and HD of MSG and soyabean significantly decreased the testosterone and LH of male rats. The colorectal, pancreatic, and ovarian cancer markers, and prostate specific antigen levels were significantly elevated after administration of MD and HD of MSG for 2, 4, and 6 months. This study has shown that the high dose administration of monosodium glutamate and soya bean produced delecterious effects on the biochemical parameters and cancer markers on rats after six months extensive administration.
Open Access
Design and modelling of smart home technologies for the aged persons
(Federal University of Technology, Owerri, 2021-07) Okoroafor, Godfrey Nwaji
Smart home technology for the aged persons here is a wireless sensor-based home system that provide the aged persons a safe, sound and secure home environment, while enabling them to live independently in their own homes as long as possible. The aged persons here are that population within the ages of 65 years and above. Nowadays, the rapid increase in the number of aged persons, including those with disabilities, the decrease in the number of family care-givers as a result of youths` migration to cities in search of white-collar jobs, and inability of government to provide adequate infrastructural needs to these aged persons has resulted in a miss-match on the caring facilities in Nigeria. These have contributed to the problem of these aged persons, since neither families nor government are able to meet their needs, especially in Africa due to high level of mass poverty, illiteracy and corruption in governance. Therefore, the task of this proposed system here is to design and model a voice activated home control system that will utilize the natural voice of the aged home occupants, to provide a more convenient, easier to install and use, user friendly home technologies for the aged persons. This will enable them maneuver assistive wheelchair, and manage home appliances through voice commands. This assistive wheelchair developed is embedded with collision detection and avoidance. The tools used to realize this proposed system are; The Personal Computer (PC), HC-SR04 ultrasonic sensor, and Voice Recognition (VR) module in a PC used for voice processing and recognition, Microphone for voice signal acquisition, C-language with the help of C# for coding. Bluetooth and Radio Frequency (RF) transceivers wirelessly link the input module to the controller module (microcontroller) which selects the appliances/assistive device to be controlled according to the input voice command. Proteus Virtual System Modelling (VSM) was used for developing smart home technology system schematic model and carried out the animated simulation to validate the system`s performance within the home. The designed system was tested on Dead Home (a home with closed curtains, carpet, an air-conditioner, and other leaving home appliances switched off) and Live Home (a home with opened curtains, carpet, an air-conditioner, television, and other leaving home appliances, switched on, and with background music or noise from a stereo people) conditions, and the effective result was 92.93% for dead home and 75.85% for live home respectively. This showed that the realized system controlled the devices with voice, though, the level of this system response is higher in dead home than in a live home, hence, the level of the system performance is lower in a noisy environment.
Open Access
Management systems for sustainble productivity of plantain ratoon crops intercropping systems in the tropical ultisol of Imo State, Nigeria
(Federal University of Technology, Owerri, 2021-07) Iwuanyanwu, Uzoma Prince
Two field experiments were conducted at Umuagwo, Imo State in 2013 and 2014 cropping seasons to investigate management systems for sustainable productivity of plantain ratoon crops intercropping systems in the tropical ultisol of Imo State, Nigeria. Experiment one was the evaluation of the effect of four organic manure sources on the growth and yield of plantain ratoon crops under different cassava densities and to evaluate weed suppressibility at varying population of plantain ratoon crops / cassava mixture. Experiment two was the evaluation of the residual effects of the organic manure sources and ash on the plantain ratoon/ cassava mixture. The organic manure sources were zero, poultry manure at 10 tons/ha, pig dung at 10 tons/ha and cow dung at 10 tons/ha. The ash was a blanket application each applied at 5 tons/ha as organic amendment. The cassava densities were 100.0 x 50.0 cm (20,000 plants/ha), 100 x 100.0 cm (10,0000 plants/ha) at 100.0 x 200.0 cm (5,000 plants/ha). Experiment one and two were all 3 x 4 factorial experiments arranged in randomized complete block design (RCBD) with 12 treatments replicated three times. Plant height (cm), number of functional leaves, stem girth (cm), leaf area (cm2), days to 50 % flowering (months), number of hands/bunch, number of suckers/plant, bunch weight (tons/ha), cassava plant height (cm), number of branches, plant canopy cover(m2), stem yield (bundles/100 stems), weed dry weight (kg/ha), cassava tuber weight (tons/ha) were the evaluated parameters. The result from experiment one showed that organic manure sources had significant effect on the growth and yield of plantain ratoon crops /cassava mixture. Poultry manure at 10 tons/ha performed significantly better in both growth and yield parameters and suppressed weeds when compared with pig dung at 10 tons/ha and cow dung at 10 tons/ha. Experiment two showed that poultry manure at 10 tons/ha + ash at 5 tons/ha performed significantly better in both growth and yield parameters and when compared with pig dung at 10 tons/ha + ash at 5 tons/ha and cow dung at 10 tons/ha + ash at 5 tons/ha. Cassava densities produced significant (P>0.05) increase in both growth and yield parameters assessed in the order of 100.0 x 100.0 cm (10,000 plants/ha) > 100.0 x 50.0 cm (20,000 plants/ha) > 100.0 x 200.0 cm (5,000 plants/ha). Poultry manure at 10 tons/ha, + ash at 5 tons/ha + 100.0 x 100.0 cm (10,000 plants/ha) cassava densities were more associated with bunch weight and tuber weight of cassava with 9.47 tons/ha for plantain and 10.52 tons/ha and 18.92 tons/ha and 19.98 tons/ha for cassava root yield both in 2013 and 2014 cropping seasons and in other yield components and may serve as a yardstick for selection of organic manure source, ash and densities. The physical and chemical analysis of the soil in both cropping seasons had that the nutrients persisted in the soil indicating that poultry manure, ash with 10,000 plants/ha cassava density had the best result in 2014 cropping seasons. For maximum production of plantain ratoon crops / cassava mixture, poultry manure at10 tons/ha + ash at 5 tons/ha with cassava density 100.0 x 100.0 cm (10,000 plants/ha) should be adopted.
Open Access
Fungitoxity of selected bio-pesticides on the storage rot diseases and biochemical composition of yam varieties (Dioscorea spp) in Owerri
(Federal University of Technology, Owerri, 2021-07) Mba, Paul Chikezie
The study was conducted at the laboratory of Crop Science and Technology, School of Agriculture and Agricultural Technology, Federal University of Technology Owerri between 2017 to 2019.This project evaluated the fungitoxicity of some bio-pesticides on the control of storage rot diseases of yam varieties (D. rotundata and D. alata) especially caused by Aspergillus spp, Fusarium spp, Rhizopus stolonifer, Yeast and B. theobromae. The fungitoxic activity of ethanol extracts of seven plant leaves (used as bio-pesticides); Chromolaena odorata, Carica papaya, Vernonia amygdalina, Ocimum gratissimum, Azadirachta indica, Psidium guajava and Cymbopogon citratus were tested in Potato Dextrose Agar (PDA) medium to determine their percentage inhibitions against the organisms isolated from the tubers. The layout for experiment was a Completely Randomized Design (CRD) with seven (7) treatments and three (3) replications. Data was collected on some chemical constituents on both yam varieties of (D. rotundata and D. alata) and seven (7) leaf extracts used for the experiment. Result revealed that D. rotundata recorded higher chemical constituents than D. alata. The results of the study showed that Azadirachta indica extracted with ethanol as bio-pesticides for the experiment was the most fungitoxic as it possessed the best level (%) of inhibition on all the organisms isolated from yam varieties of D. rotundata and D. alata this could be because it contains phytochemicals such as Alkaloids, Flavonoids, Tannins, Phenols in reasonable percentage more than other plant extracts used in this work. It substantially suppressed the growth of A. niger. Furthermore, Azadirachta indica was most fungitoxic on rot diseases of A. niger (9.8%), Yeast (11.13%) and Rhizopus stolonifer (11.53%) isolated from D. alata and D. rotundata while Carica papaya (12.0%) was found to be most effective in the control of rot diseases of Fusarium oxysporium during the investigation. The application of Azadirachta indica was able to limit the growth of all the microorganisms identified during pathogenicity test. On point of attack the varieties of D. alata and D. rotundata showed that the most susceptible point of attack on the tubers was the basal part. The losses due to pathogenic attack was significantly reduced mostly by Azadirachta indica followed by Vernonia amygdalina then Carica papaya when Ocimum gratissimum was the lowest and are therefore recommended in that sequence.
Open Access
Molecular characterization of methicillin resistant staphylococcus aureus from clinical specimens and antimicrobial activity of plant extracts against the isolates
(Federal University of Technology, Owerri, 2021-09) Ifediora, Afoma Chinwe
Staphylococcus aureus is a major bacterial pathogen that causes different community and hospital-acquired infections. S. aureus resistant to methicillin has become a big and expanding problem of concern in many developing countries. This study examined the molecular characterization and the effect of plant extracts on methicillin resistant Staphylococcus aureus (MRSA) from clinical specimens in Abia State, Nigeria using standard recommended procedures. Conventional cultural, morphological and biochemical methods were used to identify the isolates, while the antimicrobial susceptibility testing was performed by the disc diffusion method. Methicillin resistance was detected phenotypically using cefoxitin 30µg disc and oxacillin 1µg disc. Inducible clindamycin resistance was evaluated by the D-test. Polymerase chain reaction (PCR) was used to amplify genes for methicillin resistance (mecA), clindamycin resistance (ermB), beta-lactamase production (blaZ), Panton Valentine leukocidin (pvl) with 16SrRNA gene being the internal control. Sequencing was carried out on the amplified isolates. The Random Amplified Polymorphic DNA (RAPD) was implemented on the mecA strains isolated using three randomly selected oligonucleotide primers. Plant antimicrobial assay was done using the agar well technique and phytochemicals detected in the two plants tested. A total of 750 clinical specimens of blood, urine samples, wound, ear, nasal, high vaginal, urethral and ear swabs were collected from three major health facilities located in the three senatorial zones of Abia State, Nigeria. A total of 265 (35.3%) S. aureus isolates were recovered, out of which 126(47.5%) were from males and 139(52.5%) were from females, however there was no association between the prevalence and gender (p-value = 0.05) and also prevalence and age (p-value = 0.52). Phenotypic detection of MRSA using cefoxitin disc diffusion gave an MRSA prevalence of 164(61.9%) with 65(39.6%) being from urine, 3(23.1%) from wound, 31(18.9%) from high vaginal swab, 22(13.4%) from urethral swab, 4(2.4%) from ear swab, 3(1.8%) from nasal swab and 1(0.6%) from blood samples. All (100%) of the MRSA were susceptible to vancomycin, 120(73.2%) to clindamycin, 92 (56.1%) to gentamycin. All were resistant to ceftazidine, 157(95.7%) to cloxacillin, 146(89.0%) to augmentin, 136(82.9%) to ceftriaxone and 103(61.6%) to erythromycin. The MRSA strains showed much higher resistance rate than their methicillin susceptible Staphylococcus aureus (MSSA) counterparts to all tested antibiotic except clindamycin. Exactly 64(39.0%) of the MRSA were resistant to 4 classes of antibiotics indicating multi drug resistance (MDR). The overall prevalence of inducible clindamycin resistance among methicillin resistant isolates was 29(17.7%) while 66.5% xix produced beta-lactamase. Out of 40 cefoxitin positive isolates, 12 (30%) possessed mecA gene, 17.5% harboured the β-lactamase (blaZ) gene, 20% and 10% possessed the pvl gene. Dendogram analysis of RAPD-PCR amplification of mecA positive strains showed three different clones in circulation in the state. The plant extracts showed varied levels of antimicrobial activity against the MRSA isolates. The growth of the microorganisms used for the test was inhibited by the ethanolic extracts of the leaves of Alchornea cordifolia and Acalypha wilkesiana at concentrations of 50mg/ml to 200mg/ml. The inhibition zones ranged from 9.0mm to 21.0mm whereas the water extracts showed moderate activity against the isolates. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of Alchornea cordifolia ranged from 12.5-50mg/ml and 25-100mg/ml for Acalypha wilkesiana. The results of the rates of kill revealed a gradual reduction in the total viable count of bacteria from 1hr to 24hrs in all the test isolates. The phytochemical screening of the ethanol extract revealed the presence of tannins, flavonoids, glycosides, resins and carbohydrates but in variable degrees. The percentage yields of phytochemical content of the leaves of the Alchornea cordifolia plants were as follows: alkaloids (1.85%), flavonoids (1.08%), Glycosides (1.05%), saponins (4.13%), and tannins (0.70%). The use of phenotypic and molecular methods in this study provided useful information on antibiotic resistance and genetic diversity of S. aureus isolates from clinical specimens in Abia State of Nigeria. The information provided could help in monitoring the evolution of S. aureus strains in Nigeria over time.
Open Access
Prospectivity study of mineral and geothermal energy resources in parts of SouthEastern Nigerian Sedimentary Basin
(Federal University of Technology, Owerri, 2021-09) Okiyi, Ijeoma Millicent
There has been an open search for clean/renewable energy and mineral resources for economic growth using airborne geophysical surveys. High resolution airborne magnetic and radiometric data, five scenes of Landsat 8 remote sensing, SP and VES Schlumberger data of parts of Southeastern Nigerian sedimentary basin were analysed and interpreted with a view to delineate regimented mineral colonies and anomalous zones of geothermal gradient. Reduction to Equator and Vertical Derivative filters were applied to the airborne magnetic data to centre anomaly peaks over causative bodies, define shapes and edges of magnetic sources and map magnetic lineaments. Fast Line-in-sight Atmospheric Analysis for Spectral Hypercube (FLAASH) and subsequent post FLAASH band maths were applied to the remote sensing data to generate the surface reflectance data from which ratio composite and lineament maps were generated. Results showed dominant NE-SW and E-W lineament trends from Landsat and Magnetic data with subordinate NW-SE trend. 50% overlapping data windows selected for spectral analysis were used to delineate anomalous geothermal gradients. The vertical, horizontal and NTilt derivative maps were used to reveal boundaries of mafic intrusives and inclusions which are most likely controlled by the trends of deep-seated magnetic lineaments. The derivative maps were also used to enhance edges of shallow structures. Alteration zones, lithologic/geologic boundaries were revealed by radioelement ratio, ternary and total count maps and Landsat ratio map composites 4/2, 6/5 and 6/7 and PCA plots. The Source Parameter Imaging, 3D Euler Deconvolution and Magnetic Vector Inversion modelling depth estimate filters established depths to, and geometry of, subsurface magnetic structures. Results revealed shallow to deep-seated structures in the depth range of 80 m asl to >7 km bsl which must have aided development of veins and hosted lodes of intrusives and ore bodies. Shallow Curie Point Depth (< 10km), geothermal gradient > 42°C/km and heat flow > 88mW/m2 from spectral analysis procedure have been earmarked for good geothermal reservoirs. VES geoelectric sections and 2D imaging results beneath two zones of anomalous geothermal gradient between 35 to 45 (°C/km), proposed approximate models of geothermal resources as Hot Dry Rock (HDR) for Alok and geo-pressured model for Amagunze. Cylindrical/lenticular sills, inclined dykes, sparse nodules and spheres were identified from probed windows of the RTE-TMI map as surface to deep-seated models. Ground-truthing these findings, field image and double dipole results indicated mineralization of the study area as true, hence, making it a viable mineral and geothermal prospect environment.
Open Access
Molecular characterization of mycotoxin producing moulds from grains and legumes and their susceptibility to plant extracts
(Federal University of Technology, Owerri., 2021-11) Ohabughiro, Ndidi Blessing
Molecular characterization of mycotoxin producing moulds from grains and legumes and their susceptibility to plant extracts was studied. Grains and legumes were stored for a period of two and four months. They were analysed for the presence of moulds and mycotoxin producing moulds. They were also analysed for the production of different mycotoxins. Sabouraud dextrose agar, Sabouraud dextrose broth, potato dextrose agar and malt extract agar were used in this study. The methods of isolation used were direct physical examination and direct plate count method. Moulds were identified based on their colony morphology, cultural characteristics and molecular characterization. Mycotoxin analysis was done using Liquid chromatography tandem mass spectrometry. Antifungal susceptibility test was done using the Clinical Laboratory and Standards Institute approved methods for testing of moulds using disk diffusion method. The following four oxoid antifungal agents were used: Amphotericin B, fluconazole, ketoconazole and voriconazole. The following medicinal plants: Ocimum gratissimum (scent leaves), Vemonia amygdalina (bitter leaves), Gongronema latifolium (utazi leaves) and Piper guineense (uziza leaves) were assessed for their phytochemical properties and antifungal susceptibility profile against various moulds. The organic solvents used for antifungal susceptibility profile were methanol and hot water. One way analysis of variance, Duncan tests and descriptive statistics were used for statistical analysis. The moulds isolated and identified culturally were Aspergillus sp. Aspergillus flavus, Aspergillus niger, Aspergillus ochraceus, Penicillium chrysogenum, Fusarium sp, Rhizopus stolonifer, Rhizopus nigricans and Mucor sp. while those identified molecularly were Aspergillus flavus, Aspergillus tamarii, Aspergillus niger, Aspergillus brunneoviolaceus, and Penicillium chrysogenum. The genus Aspergillus was the most prevalent mould. Groundnut had the highest number of isolates followed by maize, beans, rice while wheat had the least number of isolates. The numbers of colony forming units were more in Potato dextrose agar, Sabouraud dextrose agar and least on malt extract agar. Potato dextrose agar recovered the highest number of isolates from both unstored and stored samples followed by sabouraud dextrose agar then malt extract agar. The following mycotoxins were detected Aflatoxin B1, Aflatoxin B2, Aflatoxin G1, Aflatoxin G2, Ochratoxin A, Citrinin, Dihydrocitrinone, Fumonisin B1, Fumonisin B2, Fumonisin B3, Fumonisin B4, Zearalenone, Deoxynivalenol and Nivalenol. Aflatoxin was the most frequent mycotoxin detected. Rice (1286.3 ± 29.689 µg/kg) had the highest rate of recovery of mycotoxins followed by wheat (1166.8 ± 0.901 µg/kg) and groundnuts (1142.9 ± 10.488 µg/kg) while maize (1111.6 ± 9.810 µg/kg) had the least concentration of mycotoxins. Ketoconazole (39 ±1.000 mm) had the highest minimum inhibitory concentration among different anti-fungal agents, followed by voriconazole (36 ± 2.000 mm), Amphotericin B (30 ±2.000 mm) and then Fluconazole (21 ± 12.124 mm). Susceptibility profile using only tetrazolium gave no zone of inhibition. Antifungal agents alone gave a better zone of inhibition than the combination of antifungal agents with tetrazolium. The medicinal plants such as scent leaves, bitter leaves, uziza leaves and utazi leaves analysed contained the following phytochemicals tannin, alkaloid, steroid, saponin and flavonoid. Percentage growth inhibition of moulds by methanol and hot water xiiiextract of scent leaf gave the highest inhibition followed by bitter leaf, utazi and uziza gave the least growth inhibition. Methanol extract gave a better inhibition than hot water extract at 100 mg/ml and 50 mg/ml. One-way analysis of variance and Duncan tests showed that there was a significant difference (P < 0.05) between the isolates found in stored and unstored grains and legume. There was also a significant difference (P < 0.05) between the antifungal agents and media used. Potato dextrose agar should be used frequently since it gave the highest rate of mould recovery. Ketoconazole remains the best drug of choice among other antifungal agents against moulds. Medicinal plants like scent leaves, bitter leaves, utazi leaves and uziza leaves gave varying levels of growth inhibition against various isolates and should be used both at home and clinical settings. The grains and legumes studied were contaminated with various species of moulds and contained many mycotoxins of public health importance.
Open Access
Molecular characterization of mycotoxin producing moulds from grains and legumes and their susceptibility to plant extracts
(Federal University of Technology, Owerri, 2021-11) Ohabughiro, Ndidi Blessing
Molecular characterization of mycotoxin producing moulds from grains and legumes and their susceptibility to plant extracts was studied. Grains and legumes were stored for a period of two and four months. They were analysed for the presence of moulds and mycotoxin producing moulds. They were also analysed for the production of different mycotoxins. Sabouraud dextrose agar, Sabouraud dextrose broth, potato dextrose agar and malt extract agar were used in this study. The methods of isolation used were direct physical examination and direct plate count method. Moulds were identified based on their colony morphology, cultural characteristics and molecular characterization. Mycotoxin analysis was done using Liquid chromatography tandem mass spectrometry. Antifungal susceptibility test was done using the Clinical Laboratory and Standards Institute approved methods for testing of moulds using disk diffusion method. The following four oxoid antifungal agents were used: Amphotericin B, fluconazole, ketoconazole and voriconazole. The following medicinal plants: Ocimum gratissimum (scent leaves), Vemonia amygdalina (bitter leaves), Gongronema latifolium (utazi leaves) and Piper guineense (uziza leaves) were assessed for their phytochemical properties and antifungal susceptibility profile against various moulds. The organic solvents used for antifungal susceptibility profile were methanol and hot water. One way analysis of variance, Duncan tests and descriptive statistics were used for statistical analysis. The moulds isolated and identified culturally were Aspergillus sp. Aspergillus flavus, Aspergillus niger, Aspergillus ochraceus, Penicillium chrysogenum, Fusarium sp, Rhizopus stolonifer, Rhizopus nigricans and Mucor sp. while those identified molecularly were Aspergillus flavus, Aspergillus tamarii, Aspergillus niger, Aspergillus brunneoviolaceus, and Penicillium chrysogenum. The genus Aspergillus was the most prevalent mould. Groundnut had the highest number of isolates followed by maize, beans, rice while wheat had the least number of isolates. The numbers of colony forming units were more in Potato dextrose agar, Sabouraud dextrose agar and least on malt extract agar. Potato dextrose agar recovered the highest number of isolates from both unstored and stored samples followed by sabouraud dextrose agar then malt extract agar. The following mycotoxins were detected Aflatoxin B1, Aflatoxin B2, Aflatoxin G1, Aflatoxin G2, Ochratoxin A, Citrinin, Dihydrocitrinone, Fumonisin B1, Fumonisin B2, Fumonisin B3, Fumonisin B4, Zearalenone, Deoxynivalenol and Nivalenol. Aflatoxin was the most frequent mycotoxin detected. Rice (1286.3 ± 29.689 µg/kg) had the highest rate of recovery of mycotoxins followed by wheat (1166.8 ± 0.901 µg/kg) and groundnuts (1142.9 ± 10.488 µg/kg) while maize (1111.6 ± 9.810 µg/kg) had the least concentration of mycotoxins. Ketoconazole (39 ±1.000 mm) had the highest minimum inhibitory concentration among different anti-fungal agents, followed by voriconazole (36 ± 2.000 mm), Amphotericin B (30 ±2.000 mm) and then Fluconazole (21 ± 12.124 mm). Susceptibility profile using only tetrazolium gave no zone of inhibition. Antifungal agents alone gave a better zone of inhibition than the combination of antifungal agents with tetrazolium. The medicinal plants such as scent leaves, bitter leaves, uziza leaves and utazi leaves analysed contained the following phytochemicals tannin, alkaloid, steroid, saponin and flavonoid. Percentage growth inhibition of moulds by methanol and hot water xiii extract of scent leaf gave the highest inhibition followed by bitter leaf, utazi and uziza gave the least growth inhibition. Methanol extract gave a better inhibition than hot water extract at 100 mg/ml and 50 mg/ml. One-way analysis of variance and Duncan tests showed that there was a significant difference (P < 0.05) between the isolates found in stored and unstored grains and legume. There was also a significant difference (P < 0.05) between the antifungal agents and media used. Potato dextrose agar should be used frequently since it gave the highest rate of mould recovery. Ketoconazole remains the best drug of choice among other antifungal agents against moulds. Medicinal plants like scent leaves, bitter leaves, utazi leaves and uziza leaves gave varying levels of growth inhibition against various isolates and should be used both at home and clinical settings. The grains and legumes studied were contaminated with various species of moulds and contained many mycotoxins of public health importance.
Open Access
Determination of some algebraic properties of basarab loops
(Federal University of Technology, Owerri, 2021-12) Effiong, Gideon Okon
Basarab loops are non-associative generalizations of groups and are classified as loops of non Bol-Moufang type. They are G-loops with deep algebraic and structural properties. Not much were known about the form of isotopes, holomorphs, associators, center, and subloops of Basarab loops. This work was to determine some algebraic properties of Basarab loops. The objectives of the study were to construct a Basarab loop, investigate the relationship between Basarab loop and other loops like conjugacy closed loop, abelian inner mapping loop, and Osborn loop, examine the isotopes of a Basarab loop, investigate the holomorphs and associators of a Basarab loop, and characterize some subloops of a Basarab loop. Basarab loop identities were considered and some algebraic properties of loops were investigated. Loop notions such as the use of parentheses, multiplication group, isotopy theory, and holomorphy theory, total multiplication group were examined on a Basarab loop through the governing laws of Basarab loop. Some constructions of Basarab loops were given and some algebraic properties of Basarab loops were determined. The results obtained have shown that the centrum of a Basarab loop is a subloop and it is equal to the center of a Basarab loop, and that a Basarab loop with the left (right) inverse property, or inverse property is an extra loop. Necessary and sufficient conditions for isotopes and principal isotopes of a Basarab loop were determined. It was proved that every principal isotope of a Basarab loop is a Basarab loop. It was proved that any Osborn loop is a Basarab loop if and only if it is a left (right) Basarab loop. Also, the holo morphs of a Basarab loop were investigated by considering a group A(Q) of automorphisms of a loop. Some necessary and sufficient conditions for an A(Q)-holomorph of a loop (Q, ·) to be left (right) Basarab loop, and Basarab loop were established. Some left (right) translation mapping of the holomorph of a left (right) Basarab loop was shown to be left (right) regular. It was shown that an A(Q)-holomorph of a loop (Q, ·) which satisfies the inverse property is a Basarab loop if and only if (Q, ·) is a Basarab loop and every automorphism of Q is nuclear.Some subloops of a Basarab loop which are characterized by permutations were obtained. It was proved that a Basarab loop is a centrum-abelian inner mapping loop. Relationship betweenassociators and inner mappings of a Basarab loop was defined. It was shown that the associator of any three elements of a Basarab loop is contained in the center and centrum of a Basarabloop. This study has presented additional properties of Basarab loops which are now available for applications. Therefore, it is recommended that researchers and cryptographers should usethe properties of Basarab loops determined by this study for further research and applications.
Open Access
Modelling marine accidents economic loss and the compensation in Nigeria
(Federal University of Technology, Owerri, 2021-12) Nwokedi, Theophilus C.
The aim of the study was to develop models of empirical relationships and elasticity coefficients that will serve as strategic tools for ensuring that, marine underwriters reserve adequate funds to maintain financial solvency for ensuring timely, adequate and sustainable compensation of marine accidents economic loss, for all kinds of insured marine risks, in Nigeria. The study used triangulation design method and obtained time series data on annual marine damage accidents economic costs, compensation funds reserved for insured marine risks, death and injury marine accidents, values of seaborne trade exposed to perils of the sea and per capita output, from the Nigerian Insurers Association (NIA), Central Bank of Nigeria (CBN) Statistical Reports, and Department of Petroleum Resources (DPR) offshore oil and gas incidents Reports. Questionnaire was used as survey instrument to obtain primary data on externalities costs to third party operators affected by marine oil spill accidents impacts on the marine ecosystem. The multiple regression method was used to model the relationships between the dependent and independent variables while the Log-Log constant elasticity model was used to establish the respective coefficients of elasticity. The Gross Output Model (GOM) was used to quantify the output losses occasioned by death cum injury marine accidents, for compensation purposes, while the Willingness to Accept (WTA) method of the Contingent Valuation Method (CVM) was used to evaluate the externalities costs and output losses to third party operators affected by marine accidents ecosystem damages, for purposes of providing adequate levels of compensation funds for indemnification of insured marine risks. It was found that, there exists significant relationships between shipping accidents economic loss and value of seaborne trade. The elasticity of shipping accidents economic loss to growth in value of seaborne trade over the period covered in the study shows that it was inelastic (E<1). The coefficient of elasticity of offshore O&G damage accidents economic loss to growth in maritime trade is 2.376. The mean economic costs of death and injury marine accidents to be compensated by underwriters per annum over the period is 4797662.92USD and 279181.17USD respectively with respective average rates of change of 1399708.27USD and -29587.88USD. The result also shows that, the Mean Willingness to Accept Amount (MWTA) which indicates the externalities cost of marine accidents damages to each third party operator affected by oil spill accidents and which underwriters are to provide adequate compensation is: N1,629,610 per annum per capita. The study developed the following models of relationship as contribution to knowledge: SHALt = 2430145.277 + 0.34IMPSTRADEt + 0.051EXPSTRADEt + e; and OFFALt = 123404.891 + 0.321IMPSTRADEt + 0.121EXPSTRADEt + e. InMAPREt = 11.021 + 0.364InSHALt + e; and InOGREt = 16.879 + 0.037InOFFALt + e. COMPENpercapital≥N1629610[1+ r] n ; and MPENaggegate≥N1629610[Xn][1 + r n. Also: ∆MAPREdeath≥1399708.265USD. It was recommended that compensation funds reserved by underwriters for indemnification of insured unexpired marine risks must increase proportionately in line with growth in value of seaborne trade exposed to sea perils and maritime accidents economic loss, indicated by the elasticity and rate of change coefficients.
Open Access
Management of building collapse risks in Nigeria: A post mortem investigation
(Federal University of Technology, Owerri, 2021-12) Obodoh, Dominic Anosike
The study focused on the management of building collapse risks (BCR) in Nigeria: A post mortem investigation. Management of building collapse risks has been saddled with a lot of challenges which had led to continuous rise in the risks associated with building collapse. The main objective of this research is to investigate the management of building collapse risks in Nigeria with a view to developing a framework for effective management and reduction of losses associated with building collapse in Nigeria. To achieve the main objective of the study, five specific objectives were pursued and four hypotheses were formulated to guide the study. A survey research design was adopted for data collection. The population of study was made up of key professionals in the building industry, Staff of emergency management agencies, as well as the neighbourhood of the collapsed building in the study areas and the total population is 24,229. A sample size of 1997 was determined using Taro Yamane formula for finite population, while the samples were selected using stratified random sampling technique. A total of 1860 correctly filled and returned copies of the questionnaire, representing 93% of the distributed copies of the questionnaire was used for data analysis. Data were presented using tables, bar charts and pie charts, while analysis was done using percentages, mean and relative important index (RII). The hypotheses were tested using analysis of variance (ANOVA) and principal component analysis (PCA) via SPSS, version 23 and Minitab 18. The following findings were made from the analysis: (i) The existing system of managing building collapse risks in Nigeria is poor, ineffective and cannot adequately be used to address the risks associated with building collapse. (ii) The building collapse risks that mostly impact on the building development and Nigerian economy are economic/financial risks and human related risks. (iii) The prominent challenges faced by emergency management agencies are: lack of adequate funding, coordination and collaboration, poor urban planning, etc. (iv). The study developed and validated a framework for effective management of risks associated with building collapse in Nigeria, which is the major contribution to knowledge. The study therefore recommends adequate funding and monitoring of emergency management agencies, coordination and collaboration network among all stakeholders involved in disaster management, among others.
Open Access
Gravity survey of parts of SouthWestern Nigeria
(Federal University of Technology, Owerri, 2021-12) Adejuwon, Benjamin Bukola
Ground gravity survey was carried out in the southwestern part of Nigeria within the areas underlain mainly by the Basement Complex rocks. The study area is precisely bounded by Latitudes 70 00’N – 8000’N and Longitudes 40 30’E – 6 00’E. The work is aimed at producing a comprehensive interpreted structural and geological models and maps from the gravity data as an aid to mineral investigation, structural and crustal studies. One thousand and ninety-three (1,093) gravity data points were established in an area of 18,150km2 giving a density of 1/16.6km2 . This is a positive improvement on the existing 1/9,075km2 gravity density in the area. Seventy-five (75) evenly distributed gravity base stations were established in the study area. These were tied to IGSN 71 through the PGNN Base station at Oshogbo and Akure base stations. This gives a gravity station density of 1/242km2 as against the existing density of 1/9,075km2 . The database was also saved in GIS platform for proper management and archiving. One hundred and forty-eight (148) rock samples were collected and their densities determined using a standard density determination procedure. The density values ranged from 2.526 to 2.871g/cm3 . The amphibolites have the highest mean density of 2.765g/cm3 , followed by the charnockites with 2.755g/cm3 . The processed data were presented as 2D maps with both contour and colour shaded maps. The maps include absolute gravity value map, Free-air anomaly map, Bouguer anomaly map, Regional anomaly map, residual anomaly map and rock density anomaly map of the area. The Bouguer anomaly field values range from about -19.087 to 16.914mGal, the free-air anomaly values range from 16.026 to 68.274mGal/m while the residual Bouguer Anomaly values range from about -10.577 to 19.805mGal. There is mostly a general NE/SW and few N/S trends in all the anomaly fields. Four gravity profiles across the study area were chosen for modelling and interpretation. Six major bouguer anomalies with unique characteristic features were identified. These maybe related to the contrasting lithological and structural features. These include the Ifewara-Ilesha-Ilaorogun High, AkureIkere-Igbaraoke High, Ikare-Ogbagi-Ajowa High, Ute-Uzebba High, IjeshaIsu-Ikole-Ponyan Low and Ondo-Bagbe Low. The elongated NE/SW trending bouguer anomaly at the western part of the study area termed the Ifewara-Ilesha-Ilaorogun High coincide with the geologically established shear zone associated with Ifewara-Zungeru fault system in orientation and location. Hence, the gravity data have confirmed the existence of the mega fault system which is related to gold mineralization within the Ilesha Schist belt. In the same vein, the relatively high oval shaped bouguer anomaly “Ikare–Ogbagi-Ajowa high” at the NE part of the study area can be a new frontier for mineral exploration. Such anomaly needs further exploration using other geophysical and geochemical techniques to determine its mineral potential.
Open Access
Assessment of Jatropha curcas L. as alternative nematicide in controlling root-knot nematode disease of Okra for improved yield
(Federal University of Technology, Owerri, 2022-01) Ogwudire, Ezechukwu Vincent
The assessment of Jatropha curcas L. as alternative nematicide in controlling root-knot nematode (Meloidogyne incognita) disease on Okra for improved yield was conducted in ultisols of Owerri, Nigeria. These were in 2016 and 2017 cropping seasons at the teaching and research farms of Federal University of Technology Owerri. Jatropha curcas L. cultivars; Cv ‘Illorin’, Cv ‘Kwara’ and Cv ‘Ihiagwa’ were first screened in a potted experiment for susceptibility to Meloidogyne incognita naturally endemic in the area using scoring index. Results on root-knot assessment showed no root-knot infection in either of the cultivars tested. Phytochemical investigations carried out for a Plant Based Nematicide revealed the presence of Alkaloids, Saponins, Flavonoids and Tannins in the Seeds, Roots and Leaves respectively. Laboratory test for nematicidal properties against hatchability and mortality of M. incognita was conducted using a 3x4x4 factorial experiment fitted in Completely Randomized Design with three replications. Alkaloids, Saponins, Flavonoids and Tannins applied at 0, 5 and 10 mls per thirty Juveniles (J2) for mortality and twenty egg masses for hatchability were suspended in 10 mls of distilled water respectively. Petri dishes were kept at ambient temperature after 12, 24, 48, and 72 h incubation. Results show that at 10 mls, Seed Alkaloids recorded highest mortality (99.73 %) after 72 h treatment exposure while at 5 mls, Root Alkaloids recorded highest mortality (94.73 %) after 72 h treatment exposure. Most egg hatchability reduction (0.00 i.e 100%) was achieved with Seed Saponin after 12 h treatment exposure time at 10 mls, while at 5 mls (0.08) egg hatchability reduction was achieved with Seed Saponins after 12 h treatment exposure time. Individual Plant based nematicides were further evaluated for their effects on root-gall nematode susceptible Okra variety “NHAe47-4”. Four independent 3x6 factorial experiments arranged in Completely Randomized Design with five replications were conducted in the screen house. Each nematicidal extract was applied at 0,1,2,3,4, and 5 mls, and Jatropha parts with three levelsseed, root and leaves. Results showed that all plant based nematicides applied at 5 mls/pot significantly (p<0.05) reduced root-galls and increased the growth, yield, mucilaginous property, and nutritional composition of okra. This was particularly with Leaf Tannins application which increased pod weight by 67 % and 61 % over control at 4.88 g and 5.11 g in 2016 and 2017 respectively. This was followed by Root and Seed Alkaloids which increased pod weight to 4.02 g & 4.26 g indicating 71 % and 67 % increase over control in 2016 and 2017 respectively. Seed and leaf Saponins increased pod weight to 3.62 g & 3.84 g indicating 58 % & 51 % increase over control in 2016 and 2017 respectively. Seed and Leaf Flavonoids increased pod weight to 3.56 g & 3.80 g indicating 75 % & 71 % increase over control in 2016 and 2017 respectively. Correlation analysis showed that root-knot nematode correlated negatively with growth and yield parameters of Okra. Nematicidal extracts of Jatropha curcas and plant parts at the respective rates/levels-controlled root-knot nematode (Meloidogyne incognita) infection on okra, enhanced the pod weights, Mucilaginous property and nutritional composition of okra and are therefore recommended for use in Okra production.
Open Access
Analysis of scope and economic efficiency in poultry-fish enterprises in Imo State, Nigeria
(Federal University of Technology, Owerri, 2022-02) Opara, Thaddeus C.
This study analysed the scope and economic efficiency of poultry-fish enterprises in Imo State, Nigeria. The specific objectives were to: examine the Socio economic and enterprise characteristics of fish and poultry farmers, estimate cost function from profit function to determine scope efficiency of poultry-fish enterprises, determine how scope and economic efficiency related to the use of specific inputs or the production of specific output, evaluate the determinants of scope efficiency and economic efficiency in poultryfish enterprises in the study area. A multi –stage sampling technique was used to select 210 respondents comprising of 60 fish farmers 60 poultry farmers and 90 joint poultryfish farmers. Structured questionnaire were used to elicit information from respondents while descriptive statistics, inferential statistics. Quadratic regression model, Tobit regression model and analysis of variance were used for data analysis. Findings from the study showed that most of the farmers in the three categories were males, 57.1% for fish, 62.3% for poultry and 66.7% for joint enterprises respectively. Most of the Respondents were between 41 and 60 years age bracket, 65.1% for fish 80.3% for poultry and 58.3 for joint enterprises. The distribution of respondents by marital status showed that most of the farmers were married 80.9% for fish, 75.4% for poultry and 81.9% for joint enterprises. Majority of the respondents had household sizes of 4 to 5 persons, 65.1% for fish, 55.7% for poultry and 63.9% for joint enterprises. 69.8% of fish farmers and 67.2% of poultry farmers had 6 to 10 years farming experience while majority of joint farmers (56.9% had 1-3 years of farming experience. Most sole farmers were small scale farmers 39.7% for fish and 42.6% for poultry while most joint farmers were large scale farmer (75%). The three categories of farmers had poor access to credit with only 19.4 % of joint farmer able to access above N300, 000 credits. In this research, cost functions were recovered from unrestricted profit functions and were used to calculate scope efficiency. The main scope efficiency was 0.025 indicating that the joint production of fish and poultry enterprises reduces total cost by 2.5%. The mean economic efficiencies were 0.72 for fish, 0.68 for poultry and 0.77 for joint enterprises. This indicated that farms could reduce cost by producing at the lowest possible cost. The correlation of scope and economic efficiency with output quantities was positive and significant at 1% level suggesting that the joint production of fish and poultry on the same farm resulted in cost advantage. Also the correlation of scope and economic efficiency with expense ratio were all significant at 1% level which revealed that larger farms tends to have more scope and economic efficiency scores. Again scope and economic efficiency are significantly determined by level of education, farming experience, pond size, and flock size as well as credit amount. It is recommended that educational packages and appropriate training could be necessary to teach farmers those farming practices that encourages cost complementarities and financial institutions should be encouraged to improve on the volumes and terms of loans extended to farmers.
Open Access
Development of intelligent master controller for hybridized power pool system applications
(Federal University of Technology, Owerri, 2022-11) Kufre, Esenowo Jack
The development of an intelligent master controller model for hybridized power pool system applications has become necessary in the contemporary society where much resources are allocated in a decentralized scenario which does not encourage high productivity. Many metropolitan cities are endowed with several scattered energy resources within its locality and when aggregated in a power pool, its energy resources aggregation for continuous energy supply in order to curtail energy wastage may likely be posed with the challenges associated with uncoordinated system. In view of this therefore, an Intelligent Master Controller (IMC) is proposed to oversee and regulate the unified energy potentials in some metropolitan cities in order to ensure efficiency, reliability, and optimal utilization. In the conceptual framework deployed in this study, Afikpo Metropolis was used as a case study to demonstrate a typical power pool architecture with the intelligent master controller. The network voltage level for the five experimented communities were used with respect to the available energy sources. Programmable Logic Controller (PLC) was adopted for the renewable energy synchronization and hybridization through virtual demonstration; the integration of their hybridized renewable energy sources with other available sources like the public power supply and the generating system were made possible through intelligent master controller. The intelligent master controller operation sequence was simulated with proteus software. The hardware was implemented with electronics components, whereas the remote monitoring and control was achieved with Hypertext Mark Language (HTML), Cascaded Style Sheet (CSS), JavaScript and Hypertext Preprocessor (PHP) design. The HTML, CSS and JavaScript provide an app for human and machine interactivity and MongoDB gives the data documentation platform, whereas the ThingSpeak gave the real time analytical scheme for the system. The result from the software simulation conformed with that of the hardware implementation which reveals that energy from metropolitans’ cities could be centrally monitored and controlled using intelligent master control model. This model was demonstrated remotely through the web/Android App, and the energy generated and consumed by the pooled communities were documented in the cloud. The system performance was validated within 6hours of operation, and the system reliability prediction was carried out to ascertain the model functionalities. The developed intelligent master controller model was stable, observable and controllable from the MATLAB simulation result.
Open Access
Morpho-Physiological responses and performance of chicken fed activated charcoal-aged palm sap (acaps) supplemented diets
(Federal University of Technology, Owerri, 2022-11) Ohanaka, Albert Uzochukwu Chinenye
The aim of this study is to utilize a feed additive supplement developed from a combination of activated charcoal and aged palm sap (ACAPS) for the improvement of the performance of laying hens and broilers. Pig dung, palm kernel shell (PKS), and bamboo chips blended respectively in a 4:3:3 ratio was carbonized to produce activated charcoal (AC) as a potential poultry feed additive. Thereafter, the AC was blended with raffia palm sap that was aged for 3 days in a ratio of 7:3 to produce an activated charcoal-aged palm sap (ACAPS) product as a second potential poultry feed additive. The efficacies of the AC, and ACAPS as feed grade additives were tested on laying hens, and broiler chicken. In the layer experiment, one hundred and fifty (150) Isa brown laying hens aged fifty (50) weeks were randomly assigned to five (5) groups (L1-L5) of 3 replicates with 10 birds each in a completely randomized design (CRD) experiment that lasted for 12 weeks. Five experimental diets containing either 0.00, 0.50, and 1.00% AC or ACAPS were formulated with zero AC as the control. Similar dietary supplementation of AC, and ACAPS (0.00, 0.50, and 1.00%) were used to produce the broiler starter, and finisher diets. Again, 150 Abor acre day - old broiler chicken was randomly assigned to five groups (B1 – B5) of 3 replicates with 10 birds each in a completely randomized design (CRD) experiment that lasted for 8 weeks. Data collected from the layer experiment included laying performance, egg quality, haematological, serum biochemical, and reproductive organ characteristics, while for the broilers, data on the growth performance, carcass characteristics, and economics of production were also collected. Results from the physico-chemical evaluation indicate that AC was mildly alkaline (8.49), high in carbon content (75.35%) and low in ash content (13.13%). The inclusion of the AC in the layer and broiler diets made the diets more water absorbent, increased carbohydrate, and metabolizable energy values, but decreased the BD, crude protein (CP), and other proximate values of the diets. The mineral ratios of the diets such as Ca/P, Na/K, and the dietary electrolyte balance (dEB) increased with increasing AC inclusion in the layer diets. The 1.00% AC and ACAPS supplementation resulted in 8.28, and 12.84% increase in hen-day production over the control value, and reduced loss in weight of the laying hen. All haematological, serum protein, and electrolyte values were significantly (p<0.05) decreased with increased inclusion of AC, and ACAPS supplementation, while the ovarian, and large yellow follicles (LYF) weights were increased. Litter odour and fly infestations were reduced in the pens housing the charcoal treated birds. The performance results of the broiler study showed that the birds fed the 0.5% AC (B2) recorded significantly higher (p<0.05) final weight, and weight gain, followed by the control, and B4 (0.5% ACAPS) groups after 7 days of feeding. After 28 days of feeding, the birds fed the B4 (0.50% ACAPS) diet recorded significantly higher final body weight, and weight gains (p<0.05) than the birds fed the B3, and B5 (1% AC and ACAPS) diets. Similar growth pattern was observed on the 42, and 49 days of age. However, on the 56th day, the B2 (0.50% AC) had averaged similar (P>0.05) performance with the B4 and both had superior performance indices than the rest of the group. No significant differences were observed in the carcass characteristics of the birds. The blood parameters improved progressively with charcoal addition in the broiler diets. The optimal supplementation levels or AC and ACAPS in layer diets were at 1.00% levels because of improved egg laying, growth performance, and eco-friendly poultry production environment. The optimal levels of AC and ACAPS supplementation in broiler diets stood at 0.50% levels beyond which it comes less tolerable and impacts on broiler performance. Therefore, the supplementation of ACAPS at 0.50 and 1.00% in broiler and layer diets respectively is recommended as feed grade additives for optimal performance in poultry production.
Open Access
Modelling of Nigeria’s Liquefied Natural Gas Shipping Trade
(Federal University of Technology, Owerri., 2022-12) Igboanisi, Chinaemerem C.
Nigeria has the largest proven natural gas reserves in Africa and its reserves ranked as ninth (9th) largest in the World- accounting for 188.8tcf (trillion cubic feet) of proven reserves as at the year 2019. However, Nigeria’s capacity to participate in the global natural gas shipping trade and earn freight revenue has been constrained by shipping tonnage market domination by other nations. Thus, as the nation strives to improve her revenue earnings through robust visible and invisible trade policy; it has become imperative to investigate empirically the determinants of Nigeria’s international shipping trade in Natural gas. This research developed the gravity model of Nigeria’s natural gas (NLNG) shipping trade to determine the factors affecting NLNG international freight market. The secondary data for the study comprised of volume of natural gas production (in billion cubic meters) shipped between Nigeria and other trading partner countries, geographical distance data between trading partner countries, population mass of trading partners, price of natural gas and bilateral trade agreements. Others include: logistics performance indices and shipping freight rates. These were sourced from global databases, Nigeria LNG limited, the Nigerian Ports Authority and covered the periods between years 2003 to 2020. To address the hypotheses governing this research, we developed an augmented gravity model of natural gas shipping trade in Nigeria’s international freight market and examined trends in demand. The following variables were found statistically significant in explaining NLNG trade namely: quality of transport infrastructure (-225.448), geographical distance (-232.721), trade agreement (42.534) and population mass (0.955). These coefficients are in their natural logs and can therefore be interpreted as elasticities. In terms of most important trading blocs or shipping routes, the most important shipping routes (which are dummy variables) are namely: The United States of America (3,360.056), EuroAsia (3,090.082), Europe (904.810) and South America (786.413). These findings indicate that robust policy interventions are needed to promote trade with our trading partners. Robust investments are also needed in our transport infrastructure quality (especially that of bunkering facilities for LNG vessels) in order to reduce impediments to trade. From the positive trend analysis results, demand for natural gas is positive and the federal government should encourage more private sector investment in LNG shipping fleet to increase Nigeria’s participation in LNG international freight market. As recommendation for further studies, modelling of constraints of natural gas trade involving gasification and re-gasification stations should be explored in order to expand the scope of the present work.
Open Access
Intelligent evaluation system for software quality measurement
(Federal University of Technology, Owerri., 2022-12) Nwandu, Ikenna Caeser
The concern about the large-scale and complexity of contemporary software cannot be over-emphasized. This is inclined to the assurance of standardized software quality which is essential for preventing disastrous effects of releasing fault-prone systems. This thesis designed an intelligent model that uses various metrics corresponding to six quality attributes (namely Reliability, Usability, Efficiency, Functionality, Maintainability and Portability) to measure the quality of software. This agreed to the assertion that software quality evaluation process is an instrument that observes the characteristics of a software product. In software engineering, the primary quality evaluation and assurance technique that establishes confidence over successful execution of software is termed software testing. Software testing usually identifies and applies metrics to software products in order to promote and assess their quality. This thesis designed an intelligent evaluation model in conformance with software testing principles. The objective of the model is to apply reinforcement learning in its software evaluation process to measure six software attributes in terms of speed of execution and to ensure optimal decision-making in the evaluation process, such that the model returns a reliable outcome. The model utilized a formulated model equation, whose input are the measured attributes, to achieve the evaluation. The model is developed using extreme programming principles, an agile framework whose operation is based on simplicity. It also adopted object-oriented analysis and design methodology which allowed the utilization of various artifacts including use cases, data flow, sequence, flowchart, entity-relationship and class diagrams to describe the architecture and functionality of the system. The model was implemented using Python programming language with the database design on MySQL platform. The model is further validated by comparing its performance measures on test data gotten from the functional information of Oil-palm Management Program and Estate CanePro. These tests data produced quality values of 0.9 and 1.0 respectively via the model equation. These results gave the indication that the resource software perform efficiently owing to the fact that the model’s value benchmark is best as it approaches unity. The result of comparing the outcomes showed that reinforcement learning makes software evaluation dynamic and precise. The results indicated that the model independently determines the strategies to follow during evaluations and the same set of data consistently gives the same outcome. The result also showed that the reliability of a software is directly proportional to its usability and maintainability. However, the result also showed that having a high portability value does not guarantee the reliability and/or maintainability of a given software.
Open Access
Ecological risk assessment and phytoremediation of spent engine oil contaminated soils of selected mechanic workshops in Imo State
(Federal University of Technology, Owerri, 2023-05) Azorji, Johnpaul Nnawuike
Assessment of the ecotoxicological risk of indiscriminate disposal of spent engine oil on terrestrial ecosystem was investigated using physicochemical, biochemical, and bioterance assays. Soil samples were collected from a depth of 0-20cm and analyzed using standard analytical protocols. Acute toxicity tests were conducted based on germination and seedling establishment of higher plants (Zea mays, G. maxV. unguiculata), Earthworms (mortality rate) and microorganisms (inhibitory effects) which covered a wide range of short-term lethal and sub-lethal endpoints used for risk characterization and analyzed using Probit analysis. Results obtained showed that majority of the mechanics who are within 20-30 age bracket were found in Owerri (22.42%) while the least was found in Okigwe (12.98%); on weekly basis, 42 vehicles are serviced in Owerri; 27 inOrlu while 21 is been serviced in Okigwe respectively. Total annual volume of spent engine oil generated (in litres) was highest in Owerri zone (124,489.36L) while the least value was obtained in Orlu zone (18,434.52L). A significant volume 168 (49.56%) of the spent engine oil is been disposed into the immediate environment with others being sold off 41 (12.09%); given out for free 66 (19.47%); and taken by car owners 64 (18.88%). Axonopuss compressus, Aspillia africana, and Chromolaena odorata species were the dominant plant species identified in the order: Axonopuss compressus>Aspillia africana> Chromolaena odorata. Mean values of physical and chemical properties of soil indicated alteration of parameters analyzed relative to the control. The mean concentrations of heavy metals across the zones ranged from Pb(1.045 ± 0.1 to 1.534 ± 0.2), As (1.761 ± 0.3 to 1.805 ± 0.3), Cr (0.272 ± 0.01 to 0.273 ± 0.01), Cd (0.302 ± 0.02 to 0.606 ± 0.03), Ni (0.918 ± 0.03 to 0.932 ± 0.03), Co (1.278 ± 0.1 to 1.324 ± 0.2), Fe (63.927 ± 3.34 to 69.563 ± 3.53), Cu (12.446 ± 2.14 to 12.964 ± 2.42), Zn (156.121 ± 28.01 to 156.137 ± 28.12), and Al (1.353 ± 0.2 to 1.353 ± 0.12) mg/kg with a distribution pattern of Zn>Fe>Cu>As>Al>Co>Pb>Ni>Cd>Cr. Concentration of heavy metals were significantly (p<0.05) higher at the polluted sites than the control and above WHO permissible limits. Mean concentration of PAHs ranged between Owerri zone (0.03 ± 0.01 to 1.980 ± 0.36mg/kg) Orlu zone (0.004 ± 0.001 to 1.614 ± 0.10 mg/kg), and in Okigwe zone (0.01 ±0.001 to 1.418 ± 0.19mg/kg) with distribution pattern of Nap>Pyr>Mepl>Ind>Acpt>Flu>Bbf>B(ghi)p>B(g)p>Bkf>Da>An>Acph across the zones.Maximum Concentration of TPH was recorded in Owerriwhile the minimum value was gotten from the control site. Mean values of TPH were in the order: Owerri>Orlu>Okigwe>control. Result of acute toxicity assay showed that Zea mays exhibited more sensitivity than V. unguiculata and G. max. The microbial absorbance rate depended on the dose and type of organism in the order of: Acinetobacter>Enterobacter> Bacillus species >Pseudomonas. Mortality in earthworm was noted as concentration increased. Values of Risk Quotient for Zea mays, V. unguiculata, G. max and earthworm ranged from low risk to very high risk based on the estimated PNEC values. The microorganisms differed slightly in biotolerance to spent engine oil exposure based on estimated risk quotients. Exposure to spent engine oil posed minimal risk to Pseudomonas sp., Bacillus sp., and Acinetobacter sp., at the estimated PNECs with values less than unity (<1). Risk quotient values for Enterobacter sp. indicated a high risk with values above unity. Variable xxi concentrations of heavy metals were accumulated by the plants from soil and were stored in the root, shoot and leaf except for A. compressus that accumulated values less than one (<1) for Pb and As. Metal accumulation pattern were in the order C. odorat>A.africana>A.compressus. C. odorata and A. africana exhibited characteristics typical of a phytoextractor while A. compressus could be applied as a phytostabiliser of spent engine oil polluted soils. The sensitivities exhibited by the organisms exposed to spent engine oil indicate the possibility of using them as bioindicators and for assessing the efficacy of phytoremediation process. Spent engine oil adversely affected the organisms in each scenario in a dose dependent manner. Overall, these findings proved that spent engine oil greatly altered soil properties and also repressed the growth of organisms in the ecosystem thereby strengthening the need to curb indiscriminate disposal of spent oil on the environment by mechanics in the business of auto repairs to forestall possible pollution problems of other components of the food chain.
Open Access
Geoenvironmental assessment of impacts of quarrying and quality of aggregates from various sources in parts of SouthEastern Nigeria
(Federal University of Technology, Owerri, 2023-07) Agubom, John-Kennedy
The increasing demand for sand and crushed aggregates in parts of Southeastern Nigeria has necessitated the assessment of the impacts of aggregate quarrying such as air quality, dust (suspended particulate matter) and noise which constitute serious environmental problems, including health hazards of various types of cancers, silicosis and sometimes premature death amongst quarry workers and residents of immediate community in Lokpaukwu, Amasiri, Ishiagu, Uturu and Afikpo quarry sites, Southeastern Nigeria. Nine (9) sampling points were selected for the study and they include: primary crusher, generator house, secondary crusher, blasting pit, admin block, staff quarters, entrance gate, workshop and weighing bridge.Quarrying of sand in Njaba, Nwaorie and Otamiri rivers respectively has distorted their channel morphology both in depth and width thereby threatening the neighbouring bridges and river banks. However, the physico-mechanical properties of road stone aggregates from some intrusive rock quarries were determined and the results used to evaluate the quality of the aggregates as raodstone. Four aggregate samples were collected from the following intrusive rock quarries: Lokpaukwu (Ezeaku Formation, Diorite); Uturu (Ezeaku Formation, Andesite); Ishiagu (Asu River Group; Diorite); and Afikpo (Ezeaku Formation, Dolerite). The physico-mechanical tests performed on the samples include: Aggregate Crushing Value (ACV); Aggregate Impact Value (AIV); Los Angeles Abrasion Value (LAAV); Water Absorption (WA); and Specific Gravity (SG). Results of the tests (ACV, AIV, LAAV, WA and SG) for aggregate samples from the quarries (Lokpaukwu (Diorite), Uturu (Andesite, Ishiagu (Diorite) and Afikpo (Dolerite)), respectively, are: 15.60%, 13.70%, 26.30%, 0.54% and 2.75; 19.20%, 19.01%, 19.50%, 0.01% and 2.67; 15.50%, 17.40%, 23.50%, 1.2% and 2.75; and 13.80%, 14.40%, 33.70%, 0.50% and 2.81.According to Nigerian Federal Ministry of Works Standards, the values from all the quarries are within the acceptable limits for roadstone aggregates (<30%, < 30%, <40%, <3% and >2.6), respectively. They are therefore recommended to be used as aggregates in road construction. On the other hand sandstones from Elugwu/ Umuchienta (Ameka Formation) are better than Okigwe( Nsukka Formation ) sandstones as a result of tests performed on the following parameters(ACV, AIV, LAAV, WA, BD and CCT) for aggregate quality as good for concrete material are: 35.70%, 32.60%, 46.48%, 0.90%, 1.42mg/m3 , 18.90N/mm3 and 34.50%, 36.40%, 60.70%, 0.60%, 1.63mg/m3 , 16.65N/mm3 respectively.