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An empirical study of commuters’ satisfactions with taxi service quality in Abeokuta, Nigeria
(2021) Olawole MO
Transport service provision in many urban landscapes in Nigeria is dominated by individuals and private organisations. In Nigeria, there is paucity of studies addressing commuters’ satisfaction with the service quality (SQ) of informal modes of transportation. This study examines commuters’ satisfaction with SQ of taxis in Abeokuta, Nigeria using household travel survey. The sample comprised of 272 commuters selected from 31 electoral wards in the study area. Data collected using SERVPREF questionnaire, were analysed using descriptive statistics, exploratory factor analysis, and multiple regression technique. The results indicate that the commuters’ satisfaction with taxis services is slightly above average (M = 2.69, SD = 1.29) on a scale of 1 to 5. The principal component analysis identified four factors which explained 59.06% percent of the total variance in commuters’ satisfaction with taxi services in Abeokuta. In addition multiple regression coefficients showed that only three of the factors (factor 1 (β = 0.098, P < 0.05), factor 2 (β = 0.154, P < 0.000), and factors 3 (β = 0.106, P < 0.05)) significantly influenced commuters’ perception of satisfaction with taxis. The study concludes that taxis service providers need to improve on aspects of services rated low by respondents and to embrace recent trend in taxis services provision as obtainable in advance countries, while the state government should plan towards introducing bus rapid transit system (BRT) in Abeokuta and other major cities in Ogun state in the nearest future.
Analysis of the current situation and future outlooks for pigeon pea (Cajanus Cajan) production in Oyo State, Nigeria: A Markov Chain model approach
(2021) Fatokimi EO; Tanimonure VA
Pigeon pea is an underutilized crop in Nigeria and particularly in Oyo State in terms of research, production and utilization despite its economic and nutrition importance. It is therefore important to understand its current production status in Oyo State in order to evaluate the economic potential of pigeon pea production in the study area. This study therefore, profiled the current production systems of pigeon pea, analyzed the current and forecast the future farm size and examined the constraints to pigeon pea production in Oyo State. Multistage sampling procedure was used to select 150 pigeon pea farmers. A structured questionnaire was used to gather primary data from the respondents. The data were analyzed using descriptive statistics, Markov Chain Analysis (MCA) and Importance Ranking Index. The study found that all the farmers still cultivated local variety with average yield of 604kg/acre, most farmers intercropped with other crops and produced mainly for consumption by households and sale at the local market. Majority (73%) cultivated between 1 and 5 acres of land and on the average, 1.55 and 1.72 acres of land were cultivated in 2017/2018 and 2018/2019, respectively. There was significant difference between the land area cultivated to pigeon pea in 2017/2018 and 2018/2019 (−1.63, p < 0.05). The results of MCA revealed that there was high probability for the farmers to remain on their farm size initially cultivated. Although, gradual increase in the farm size was observed in the equilibrium year. The persuasive identified constraints included inadequate capital, pricing problem and lack of improved variety. The study concluded that the outlook of pigeon pea production seems promising as revealed by the farm size cultivated at the equilibrium year, but a deliberate effort must be made to promote the production of and research on pigeon pea in the study area, especially in the development of improved varieties.
Application of the AquaCrop model in decision support for optimization of nitrogen fertilizer and water productivity of soybeans
(2021) Adeboye OB; Schultz B; Adeboye AP; Adekalu KO; Osunbitan JA
Modelling of the effects of water and different levels of nitrogen on evapotranspiration and water productivity of rainfed soybeans is very important in optimising resource use in the production of the crop. The objective of the study was to model evapotranspiration, soil water storage and water productivity of rainfed soybeans under different levels of nitrogen fertilizer by using the FAO AquaCrop model. Field experiments were conducted at the Teaching and Research Farms of Obafemi Awolowo University, Nigeria in the rainy seasons of 2015 and 2016. There were five levels of nitrogen, which are 00, 25, 50, 75 and 100% of the recommended nitrogen applications and two varieties of soybeans, which produced a 2 by 5 factorial experimental design. The data of the wetter year 2015, were used for calibration of the AquaCrop model because AquaCrop is water driven. The 2016 data were used for the validation. The AquaCrop model simulated canopy cover with R2 and EF > 0.90, d-index ≥ 0.99. The model captured the trend of the soil water storage well, R2 and EF ≥ 0.70. The AquaCrop model simulated soil water storage below wilting point for seasonal rainfall less than 600 mm, and it did not overestimate it. The model predicted evapotranspiration with R2 and EF ≥ 0.89, d-index = 1.00. Above ground biomass was overestimated even though R2 ≥ 0.98. Although, nitrogen stress reduced seed yield and water productivity, there was no under or over estimation of the seed yields. They were predicted with low error under the different levels of nitrogen fertilizer, R2 ≥ 0.99, EF and d-index ≥ 0.99. The AquaCrop model is suitable for simulating canopy cover, soil water storage, evapotranspiration, and seed yield of rainfed soybeans with different levels of nitrogen fertilizer under temporal distribution of seasonal rainfall. Therefore, it can serve as a useful tool for smallholder farmers in predicting productivity of soybeans and optimising resource allocation, land and water use in the tropical farming systems. We recommend simulation of the effects of pest on biomass, seed yield and water productivity by subsequent versions of the AquaCrop model. In addition, incorporating an economic sub-unit in the model will enable users to make financial decisions.
Assessing the impacts of land use on riparian vegetation dynamics in Osun State, Nigeria
(2021) Borisade TV; Odiwe AI; Akinwumiju AS; Uwalaka NO; Orimoogunje OI
The existence of riparian vegetation is greatly threatened by change in land uses in Nigeria and information on historical management of land use which influences riparian vegetation dynamics is critical to the conservation of plants species diversity. This information is poorly understood especially in Nigeria and by extension in Africa. This study therefore assessed the areas covered by riparian forests in Osun State, Nigeria in order to identify the main drivers of its decline using optical remote sensing data. It also assessed the availability and distribution of the riparian forests over three decades (1986–2016) using Landsat Enhanced Thematic Mapper (ETM). Results showed that the riparian forests covered 546.18km2 (6.40%) with about 308riparian forests distributed across the state in 1986 but had declined to 176 by 2016. Three decades later, areas covered by riparian forests decreased to171.69km2 (2.01%), representing a decline of about 69% and was predicted a rapid transition to disturbed lands. Human activities such as logging, farming, grazing and construction have greatly influenced the riparian vegetation cover with obvious decline in extent, distribution and quality. Observation from our case study showed that the disappearance of these forests is taken place at a rate that is faster than the predicted level of the Nigerian riparian forest loss by 2040. Notably deforestation, agriculture and urbanization are the main drivers of this decline, of the African gallery forests.
Assessment of heavy metal bioremediation potential of bacterial isolates from landfill soils
(2021) Oziegbe O; Oluduro AO; Oziegbe EJ; Ahuekwe EF; Olorunsola SJ
Indiscriminate disposal of wastes on landfills has led to increase in heavy metal contamination in landfill soils. However, the ability of the indigenous microorganisms to remediate the polluted environment can be of great influence in reclamation of such soils. The objectives of this study were to assess the bioremediation potential of the screened indigenous bacteria and evaluate the effects of carbon source and pH in the enhancement of the bioremediation process. Bacterial isolates from landfill sites were screened for their capability to utilize heavy metal (Cd and Pb). Nutrient Agar was supplemented with five different concentrations of each metal (25 to 600 mgL-1). Viable counts of the isolates were taken four times at two days interval. Pseudomonas aeruginosa, Klebsiella edwardsii and Enterobacter cloacae were selected based on their tolerance to heavy metal for remediation process. Peptone broth was also supplemented using different concentrations of heavy metals. The remediation process was assessed by monitoring the growth of biomass using UV spectrophotometer at 600 nm and the residual heavy metal was evaluated after 8 days of incubation using AAS. Pseudomonas aeruginosa exhibited the highest bioremediation potential among the bacterial isolates with 58.80 and 33.67 remediation percentage in 50 mg Cd L-1 and 300 mg Pb L-1 . However, higher remediation percentage (79.87 and 92.41) was observed by Klebsiella edwardsii through addition of carbon source (5 g/L) and varying the pH (6) of the media in the heavy metal contaminated medium. The results of this study indicate that the effectiveness of the indigenous bacteria in remediation process can be enhanced through the addition of carbon source and increase pH for effective reclamation of contaminated soil.
Assessment of heavy metal pollution in soil samples from a gold mining area in Osun State, Nigeria using proton-induced X-ray emission
(2021) Fagbenro AA; Yinusa TS; Ajekiigbe KM; Oke AO; Obiajunwa EI
This study identified and determined the concentration of heavy metal contaminants in Igun, Ijana-Gada and Igbadae gold mining sites using Particle Induced X-ray Emission (PIXE) technique. This was with a view to providing information on various heavy metal concentrations, potential sources of metals contamination and pollution load at Igun, Ijana-Gada and Igbadae gold mining sites. A total of thirty soil samples were collected randomly from Igun, Ijana-Gada and Igbadae gold mining sites in the Ilesha area, Osun State. Twelve samples were collected each from Igun and Ijana-Gada sites; while six samples were collected from Igbadae site. The soil samples were processed and analyzed for selected heavy metals (Fe, Mn, Cu, Zn, Cr, M, V and Fe). A Multivariate statistics approach (Pearson Correlation Matrix and Principal Component Analysis) was used on the data for identification of contamination sources. The heavy metal concentrations in the studied soils decreased in the following order: Fe > Ti > Mn > V > Cr > Zn > Pb > Cu with mean value of Fe (84,470.60 mg/kg), Ti (15,337.30 mg/kg), Mn (576.80 mg/kg), V (465.90 mg/kg), Cr (304.10 mg/kg), Zn (103.90 mg/kg), Pb (38.60 mg/kg), and Cu (26.00 mg/kg). The result obtained from the assessment of heavy metal pollution using Enrichment Factor (EF), Pollution Load Index (PLI), and Pollution Index (PI) confirmed that Igun, Ijana-Gada, and Igbadae soils/mine-tailings were polluted in the range from slightly through moderately polluted up to highly polluted. Principal Component Analysis (PCA) extracted three major components: PC1with loading of Fe, V, Zn, and Cu, PC2 with high loading of Ti and Mn while PC3 with the contribution of Pb and Cr. This was corroborated by Pearson Correlation Matrix (PCM) for the analyzed elements. The study revealed that the soils and mine tailings from the study area were polluted with heavy metals especially V, Ti and Cr from anthropogenic sources with little crustal material contributions thereby posing serious environmental and health concerns.
Atmospheric particulate fractions from Nigerian crude oil spillage
(2021) Adesanmi AJ; Okedere OB; Sonibare JA; Elehinafe FB; Fakinle BS
Laboratory simulations of the spill behaviors of three different Nigerian crude oil samples over three media (fresh water, sea water and soil) were carried out with a view to determining the effect of crude oil spillage on emission of fine (PM2.5) and inhalable particulates fractions (PM10). The spillage experiments were carried out in an environmental test box fitted with equipment to regulate the micro climatic conditions (temperature and Relative humidity). The maximum concentrations of PM2.5 were 711, 689 and 680 µgm−3 while those of PM10 were 972, 946 and 940 µgm−3 for sample A, B and C respectively. These peak concentrations were obtained for spill conditions corresponding to fresh water at 45 °C and 49% relative humidity. The least concentrations of PM2.5 and PM10 emitted across all samples were 63 µgm−3 and 256 µgm−3 respectively and these corresponded to spillage over sea water at 15 °C and 80% relative humidity. These concentrations clearly exceeded the short time averaging period (24 h) standards set for PM2.5 and PM10 by the United States Environmental Protection Agency. Incessant crude oil spillages in the Nigerian oil fields are therefore predicted to cause degradation of air quality within a short duration from the spill.
Can occupational safety and health problems be prevented or not? Exploring the perception of informal automobile artisans in Nigeria
(2021) Afolabi FJ; de Beer P; Haafkens JA
It is well-known that informal workers in developing countries run a high risk of Occupational Safety and Health Problems (OSH problems). However, little is known about their perception of the preventability of these problems. This study explores how informal automobile artisans in Nigeria perceive the preventability of OSH problems and possible barriers to prevention. 43 artisans were purposively interviewed. Only one third of the participants perceived OSH problems as preventable while a majority perceived OSH problems as not preventable. Their perception of the causes of OSH problems and cost considerations strongly influenced their perceptions of the preventability of OSH problems. The major perceived barrier to prevention is economic insecurity and, as a consequence, non-availability of modern equipment. The study concluded that availability of accessible loans and regular training of the artisans may be helpful in preventing and reducing OSH problems in the informal sector.
Cellgevity® attenuates liver distruption, oxidative stress and inflammation in STZ-diabetic male rats
(2021) Ogunlabi OO; Adegbesan BO; Ezima EN; Adebisi AA
The imbalance between reactive oxygen species (ROS) production and the innate antioxidant defence promotes oxidative distress and contributes to tissue dysfunctions which are the hallmark of diabetic complications. Diabetic hepatic injury is less reported, yet it is a target organ damage condition related to diabetes. This study investigated the hepato-protective potentials of Cellgevity® in Streptozotocin (STZ)-diabetic male rats. The rats were assigned into – Control group and diabetes induced groups (DM-untreated, DM-treated 1 and DM-treated 2 groups respectively). Separate treatment of the DM-treated 1 and DM-treated 2 groups with therapeutic doses of Cellgevity® (25 mg/kg and 40 mg/kg BW respectively) was conducted for 30 days, while the control and DM-untreated groups receieved oral distilled water (placebo). The animals were then sacrificed and their sera were evaluated for total antioxidant status and biomarkers of hepatic function. The rats’ liver homogenates were also evaluated for inflammation, nitric oxide, lipid peroxidation and antioxidant enzymes activity. Treatment with Cellgevity® significantly increased the serum total antioxidant status (2 fold) and it reduced the serum ALT, AST, ALP and bilirubin levels compared to untreated diabetes by at least 1.4 fold. Hepatic activities of glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) were significantly increased by over 130%, while liver TNF-α, nitrite and MDA levels were reduced by over 140% compared to the diabetic untreated group. The results present promising evidence for the therapeutic potential of Cellgevity® against diabetes-induced liver dysfunction, which might be through the modulation of ROS and inflammation production respectively.
Characterization of barite ores from selected locations in Nigeria for drilling fluid formulation
(2021) Abraham EI; Bayode BL; Olubambi PA; Adetunji AR; Onwualu AP
Barite is a non-metallic mineral composed of barium sulfate and is largely used by the oil and gas industry during drilling operations to control reservoir pressure. According to the American Petroleum Institute (API) standard, the specific gravity of barite should be a minimum of 4.1 to be applied as an additive in drilling fluid. In Nigeria, barite deposits are found in veins and cavity fillings hosted by varieties of rocks. Despite the abundance of barites reserves in Nigeria, the barites used in the Nigerian oil industry are imported from other countries. Therefore, in this research, barite deposits in some selected troughs in Nigeria were sampled and studied to determine their chemical composition and suitability as drilling fluid additives. The specific gravity of barites in the following states: Nasarawa, Benue, Plateau, Cross River, and Taraba was determined using the Pycnometer method, and their values were found to range from 2.9 to 4.3 on average. The quality of barite varies from location to location and with depth. The barite quality was enhanced when some low-grade barites were blended with a high grade, as shown in the blended samples of Plateau States, where specific gravity increased from 2.9 to 3.7. The results of XRF, E.D.X. and S.E.M. analysis of the samples show a predominance of BaO, Fe2O3, SrSO4, and SiO2. Samples from Benue (89.4% BaSO4) and Taraba (96.5% BaSO4) States met API standard for drilling mud application in terms of chemical composition, specific gravity, and a particle size distribution, while samples from Cross River (83.16% BaSO4), Nasarawa (77% BaSO4), and Plateau (10.88% BaSO4) States need to be upgraded to meet the standard for usage as drilling fluid additives. However, they can be used as extenders or fillers in the rubber and paper industry.
Clinicopathologic features of forehead prayer marks in Kano, Northwest Nigeria
(2021) Omeje KU; Famurewa BA; Adebola RA; Agbara R; Amole OI; Fomete B; Suleiman A
Prayer marks are asymptomatic nodular and cyst like swellings or callosities with or without chronic skin changes attributable to repeated, prolonged pressure and friction exerted on bony prominences when praying on hard surfaces. This study aimed to describe the clinical and pathological features of forehead prayer marks in Kano, Northwest Nigeria. A retrospective review of Muslims with regular praying habits who presented to the maxillofacial surgery clinic of Murtala Mohammed Specialist Hospital, Kano within a five year (January 2014–December 2018) period on account of central forehead nodular prayer marks was conducted. Biographic data, duration, size, consistency and histological diagnoses of forehead prayer marks were retrieved and analysed. Of the 26 patients with forehead prayer marks, there were 19 men (M: F = 2.7:1). The mean age was 42 ± 3 years and there ages ranged from 15 to 62 years. The mean duration and size of the swellings were 1 ± 5.4 years and 2.5 ± 3.1 cm respectively. The consistency of the lesions was mostly soft to firm (n = 23). Seventeen of the lesions were histologically diagnosed as lipoma. Others were fibroma, soft tissue cysts, eosinophilic granuloma and osteoma. Forehead prayer marks are more common in men than women with highest occurrence in fifth decade of life. Lipoma was the commonest post-excision histological diagnosis of forehead prayer marks.
Combustion and emission study of sandbox seed oil biodiesel performance in a compression ignition (CI) engine
(2021) Akintunde SB; Obayopo SO; Adekunle AS; Obisesan OR; Olaoye OS
Transportation is a crucial aspect of global development and the utilization of fossil fuels in most combustions systems seems inevitable. This class of fuel has led greatly to worldwide environmental pollution with its attendant effects on human health and climate changes. Biofuels from biomass are sustainable and viable alternatives that can eliminate the problems associated with petroleum fuels and are most compatible with the existing combustion systems. Biodiesel will further ensure positive energy equilibrium through the conservation of natural resources to improve economic stability, environmental safety and a balanced ecosystem. Most previous works make use of edible oils, which can lead to food security and price challenges. With the abundance of non-edible oil sources unexploited, the choice of this study is directed towards producing biodiesel from a non-edible seed with little or no information on its combustion properties. This study extracted Sandbox (Hura crepitans) oil chemically using analytical n-hexane as solvent and subsequently produced biodiesel from the oil via one step-transesterification. The biodiesel was characterized according to global standards for biodiesel (ASTM D6751 and EN 14214) and blended with petrodiesel to give five fuel samples (D100, B10, B20, B30 and B100). These fuels were combusted in a compression ignition (CI) engine test bed to determine its performance and emission characteristics. The results showed that the Sandbox seed produced oil with a good oil yield of 47.77% and the biodiesel produced had a yield of 86.49%, which satisfies the recommended global standards. B10 exhibited the best and highest BTE after D100 at all the torque levels (4 Nm, 6 Nm and 7 Nm) as well as the least and the most desirable emission of CO2 when compared with all the other fuels. The utilization of Sandbox biodiesel in combustion ignition engine was found to be a viable option at enhancing biofuel utilization and reduction of pollutant emissions from the present combustion of fossil fuels.
Comparative performance of limestone calcined clay and limestone calcined laterite blended cement concrete
(2021) Musbau KD; Kolawole JT; Babafemi AJ; Olalusi OB
The global availability and abundance of clay soil and limestone have recently driven research for their combined use as supplementary cementitious material (SCMs). In tropical regions, laterite (which has similar chemical signature to clay) naturally abounds in larger quantities and can potentially be used in place of clay soil as SCM. This is the focus of this study which experimentally evaluates the comparative performance of concrete made from limestone calcined clay, limestone calcined laterite and calcined laterite as supplementary cementitious materials by simple test methods. The replacement of the Portland cement with these SCMs was up to 45% to achieve low-carbon cementitious materials. The cementitious materials were characterised and four concrete mixes (100% ordinary Portland cement; 15-30-55% of limestone-calcined clay-Portland cement; 30–70% of calcined laterite-Portland cement; and 15-30-55% of limestone-calcined laterite-Portland cement) were formulated to showcase their performance in terms of workability, strength, and durability. The possibility of a differing influence of varied water-to-binder ratio on the clay and laterite SCMs was also examined. The results show no significant difference between the performance of the laterite-based and clay-based blended cement concrete. It was concluded that laterite can be interchangeably used in place of clay in limestone calcined clay cements (LC3), especially in tropical regions where laterite is in abundance as much as or more than clay. Further investigation is recommended for long term performance evaluation.
Computational screening of phytochemicals from three medicinal plants as inhibitors of transmembrane protease serine 2 implicated in SARS-CoV-2 infection
(2021) Oyedara OO; Agbedahunsi JM; Adeyemi FM; Juárez-Saldivar A; Fadare OA; Adetunji CO; Rivera G
Background SARS-CoV-2 infection or COVID-19 is a major global public health issue that requires urgent attention in terms of drug development. Transmembrane Protease Serine 2 (TMPRSS2) is a good drug target against SARS-CoV-2 because of the role it plays during the viral entry into the cell. Virtual screening of phytochemicals as potential inhibitors of TMPRSS2 can lead to the discovery of drug candidates for the treatment of COVID-19. Purpose The study was designed to screen 132 phytochemicals from three medicinal plants traditionally used as antivirals; Zingiber officinalis Roscoe (Zingiberaceae), Artemisia annua L. (Asteraceae), and Moringa oleifera Lam. (Moringaceae), as potential inhibitors of TMPRSS2 for the purpose of finding therapeutic options to treat COVID-19. Methods Homology model of TMPRSS2 was built using the ProMod3 3.1.1 program of the SWISS-MODEL. Binding affinities and interaction between compounds and TMPRSS2 model was examined using molecular docking and molecular dynamics simulation. The drug-likeness and ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties of potential inhibitors of TMPRSS2 were also assessed using admetSAR web tool. Results Three compounds, namely, niazirin, quercetin, and moringyne from M. oleifera demonstrated better molecular interactions with binding affinities ranging from -7.1 to -8.0 kcal/mol compared to -7.0 kcal/mol obtained for camostat mesylate (a known TMPRSS2 inhibitor), which served as a control. All the three compounds exhibited good drug-like properties by not violating the Lipinski rule of 5. Niazirin and moringyne possessed good ADMET properties and were stable in their interactions with the TMPRSS2 based on the molecular dynamics simulation. However, the ADMET tool predicted the potential hepatotoxic and mutagenic effects of quercetin. Conclusion This study demonstrated the potentials of niazirin, quercetin, and moringyne from M. oleifera, to inhibit the activities of human TMPRSS2, thus probably being good candidates for further development as new drugs for the treatment or management of COVID-19.
COVID-19 and sustainable development goals (SDGs): An appraisal of the emanating effects in Nigeria
(2021) Fagbemi F
The paper appraised the emanating effect of COVID-19 on sustainable development goals (SDGs) in Nigeria through the systematic illustration of the prevailing incidents. It was affirmed that the preoccupation with the COVID-19 cases caused many other critical socioeconomic issues (like education, infrastructure development, and employment) to suffer a state of negligence or be overlooked. Like other developing countries, Nigeria could become poorer, given the increased unemployment rate and the anticipated difficulty in servicing debt resulting from the COVID-19 outbreak. Hence, festering challenges including poverty, limited access to health care, low education quality, poor road networks among others, could be further entrenched. These incidents could be detrimental to sustainable development goals (SDGs) 2030 agenda. The current crisis, therefore, poses a threat to Nigeria’s development prospects, as it may take more time to recover, especially in the post-COVID-19 era. Thus, it is critical to recognize the significance of securing strong institutional regulatory setup and resources (including financial and material resources) needed to facilitate sustainable change in the economy.
Deep multiple-instance learning for abnormal cell detection in cervical histopathology images
(2021) Pal A; Xue Z; Desai K; Aina F Banjo A; Adepiti CA; Long LR; Schiffman M; Antani S
Cervical cancer is a disease of significant concern affecting women's health worldwide. Early detection of and treatment at the precancerous stage can help reduce mortality. High-grade cervical abnormalities and precancer are confirmed using microscopic analysis of cervical histopathology. However, manual analysis of cervical biopsy slides is time-consuming, needs expert pathologists, and suffers from reader variability errors. Prior work in the literature has suggested using automated image analysis algorithms for analyzing cervical histopathology images captured with the whole slide digital scanners (e.g., Aperio, Hamamatsu, etc.). However, whole-slide digital tissue scanners with good optical magnification and acceptable imaging quality are cost-prohibitive and difficult to acquire in low and middle-resource regions. Hence, the development of low-cost imaging systems and automated image analysis algorithms are of critical importance. Motivated by this, we conduct an experimental study to assess the feasibility of developing a low-cost diagnostic system with the H&E stained cervical tissue image analysis algorithm. In our imaging system, the image acquisition is performed by a smartphone affixing it on the top of a commonly available light microscope which magnifies the cervical tissues. The images are not captured in a constant optical magnification, and, unlike whole-slide scanners, our imaging system is unable to record the magnification. The images are mega-pixel images and are labeled based on the presence of abnormal cells. In our dataset, there are total 1331 (train: 846, validation: 116 test: 369) images. We formulate the classification task as a deep multiple instance learning problem and quantitatively evaluate the classification performance of four different types of multiple instance learning algorithms trained with five different architectures designed with varying instance sizes. Finally, we designed a sparse attention-based multiple instance learning framework that can produce a maximum of 84.55% classification accuracy on the test set.
Effect of compost extract processing parameters on the growth and yield parameters of Amaranthus and Celosia Vegetables
(2021) Oyewusi TF; Osunbitan JA
In an effort to provide a more affordable fertilizer alternative to farmers, the effect of compost extract processing parameters was investigated on the growth and yield parameters of vegetables. In order to extract nutrients from compost, composted chicken manure was steeped in a container of a predetermined water and subjected to three processing parameters (compost to water ratio, steeping time and water temperature) at different levels. The compost extract produced was used for production of Amaranthus and Celosia vegetables through fertigation by pot experiment in a screenhouse. The growth and yield parameters of the vegetables were determined using standard procedures. The results showed that highest values of growth and yield parameters were obtained in vegetables with fertigation of compost extract compared to the control. The three processing parameters of the applied compost extract significantly (p < 0.05) affected growth and yield parameters of both vegetables. The maximum growth and yield parameters for both vegetables occurred with fertigation of extract made under compost to water ratio of 1:3 when steeped for 72 h at 25 °C water temperature. Therefore, compost extract is well suitable for vegetables production.
Effectiveness of different alpha lattice designs in the evaluation of maize (Zea mays L.) genotypes in a rainforest agro-ecology
(2021) Akinwale RO; Odunlami LK; Eze CE; Oladejo AS
Plant breeding experiments require the use of appropriate experimental designs that will efficiently block variation due to wide heterogeneity nature of tropical soils. The primary objective of this study was to assess the effectiveness of eight different alpha-lattice designs relative to randomized complete block design for evaluating 108 genotypes of maize under rainforest agro-ecology. The maize genotypes were field-tested using three replications at two locations. Data were collected on grain yield and other agronomic traits. Data collected were subjected to analysis of variance (ANOVA) assuming randomized complete block design (RCBD) and eight alpha-lattice designs. Pearson's correlation and stepwise multiple regression analyses were used to analyze relationship among different designs and efficiency of the lattice designs over RCBD was computed. Result showed that all the alpha lattice designs except 27 × 4 were effective in evaluating the genotypes for plant height. There was significant difference (p < 0.001) among genotypes for grain yield only when data were analyzed based on 9 × 12 alpha lattice design. In addition, results showed that the proportion of variation due to blocking and R-square values of the model increased with increase in the number of blocks for grain yield. In contrast, coefficient of variation decreased with increase in the number of blocks. The result showed an increase in efficiency of the alpha lattice designs as the number of blocks increased. It could then be concluded that the more the number of blocks within replicate, the proportion of total variation due to blocking increased, the coefficient of variation (CV) reduced, coefficient of determination (R-square) increased and thus, effectiveness increased. Appropriateness of designs was trait dependent. The 9 × 12 alpha lattice design was identified to be the best in the evaluation of grain yield for the maize genotypes.
Effects of cypermethrin as a model chemical on life cycle and biochemical responses of the tropical stingless bee Meliponula bocandei Spinola, 1853
(2021) Chibee GU; Ojelabi OM; Fajana HO; Akinpelu BA; Kehinde TO; Awodiran OM; Obuotor EM; Owojori OJ
The tropical stingless bee, Meliponula bocandei Spinola, 1853 is an important pollinator in West Africa but there is no study on the effect of pesticides on this species. This study assessed the effects of cypermethrin, a common pyrethroid on survival, taste (sucrose sensitivity), and biochemical responses of M. bocandei. The biochemical markers were superoxide dismutase [SOD], catalase [CAT], glutathione S-transferase (GST), reduced glutathione [GSH]), and acetylcholinesterase [AChE]) as well as glucose, trehalose and total protein concentrations. Test temperature was optimized by acclimatizing adult worker bees collected from a pristine natural colony to different temperature regimes in the laboratory and fed with sucrose solution. The optimized temperature (22°C) for survival and sucrose consumption was adopted for the toxicity test. The 24–48 h oral lethal dose (LD50) and 24–96 h indirect contact lethal concentration (LC50) of cypermethrin on the bees was in the range of 0.66–0.76 µg/ml and 92.24–223.69 µg/ml respectively. Also, the overall PER response reduced below 50% in bees that were orally exposed to high doses of cypermethrin. There was significant decrease in glucose, trehalose, total protein and GSH concentrations in bees when compared with the control. Also, significant alterations were observed in SOD, CAT, GST and AChE activity for both oral and contact exposure pathways. In conclusion, cypermethrin modulated the activities of biomarkers of oxidative stress and altered the level of energy metabolites in the bees.
Energy research in Nigeria: A bibliometric analysis
(2021) Adedayo HB; Adio SA; Oboirien BO
The scant supply of energy in Nigeria in relation to its energy demand has triggered interest in the scientific investigation of various energy research. This study reports on the bibliometric analysis of energy publications from Nigerian researchers from 1974 to 2019 (45 years) from the Elsevier Scopus database. The analysis includes publication types, languages of publication, institutions of authors and collaborators. Based on the analysis, the number of publications has increased in the 45 years period. With significant changes being from the period 2006–2015 by an average of 113 publications per year, to an average of 326 publications per year from 2016 to 2019. The contributions of institutional energy publications by region showed that the South-Western States region had the highest number of publications. A global map showing energy collaboration at international level Nigerian-authors mainly co-author energy publications with South Africa, Malaysia, the United States and the United Kingdom institutions. The publications are mainly in solar energy, wind energy and biomass energy and surprisely less in gas and hydro energy which are the main sources of electricity generation in Nigeria.

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