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he stochastic frontier analysis (SFA) model, designed to assess technical efficiency in production models, operates under the assumption of homoscedasticity. However, in practical scenarios, either the random error or the technical efficiency error, or both, can exhibit non-homoscedasticity. This research proposes heteroscedasticity correction measures for the random error (HCRE), technical efficiency error (HCTE), and both (HCRTE) within the SFA model. The study aims to determine which correction measure yields the most efficient parameter estimates when heteroskedasticity is present. The comparison involves evaluating the mean squared error (MSE) across different forms of heteroscedasticity and sample sizes through Monte Carlo simulations comprising 5000 replications. The findings indicate that attempting to correct for heteroskedasticity in the absence of such issues can adversely affect the parameter estimates of the SFA Model. Conversely, the HCRTE measure consistently produces the most efficient estimates when dealing with heteroskedasticity in terms of both random error and technical efficiency. Moreover, in cases where heteroskedasticity exists, applying the HCRTE measure not only enhances parameter estimates but also improves the technical efficiency measure of the SFA model.

Efficiency estimation in production technology has been a concern in economics, with methodologies such as Stochastic Frontier Analysis (SFA) playing a key role in this area. SFA has been pivotal in evaluating the efficiency of entities by isolating technical inefficiency from random production errors. However, despite its significance, the application of SFA faces challenges when the multicollinearity assumption underlying the model is violated. Therefore, this study presents a novel estimator, termed “Principal Component Analysis Estimation for Stochastic Frontier Analysis” (PCA-SFA), to address the problem of multicollinearity in the classical SFA model. The PCA-SFA estimator integrates Principal Component Analysis (PCA) to correct assumption violation arising from multicollinearity. Monte Carlo simulation study was conducted to ascertain the PCA-SFA performance, involving no fewer than 2,000 replications based on the Cobb-Douglas production function with varying levels of multicollinearity, represented by correlation coefficients ranging from 0.8, 0.9, 0.95, 0.99, and 0.999, and sample sizes (n) of 20, 50, 100, 250, and 1,000. The proposed estimator’s performance was compared to the classical SFA model using the Mean Square Error (MSE), Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC) as evaluation metrics. The results demonstrate that the PCA-SFA estimator consistently outperforms the classical SFA model. The PCA-SFA model showed significantly lower MSE, AIC, and BIC values, indicating improved precision and reliability in parameter estimation. The study, therefore, recommends that researchers and practitioners in econometrics and related fields consider integrating PCA-SFA into their production efficiency analytical frameworks, particularly when dealing with datasets prone to multicollinearity issues.

LogMAR charts are particularly useful for visual acuity (VA) measurement for low vision patients as they simplify conversion of non-standard viewing distance visual acuities to standard values. Also, the process of predicting various quantities involved in the prescrip-tion of optical devices for patients are greatly facilitated. However, the processes involved in the use of this logMAR principle require series of multiplication and division by the logMAR ratio of 1.2589. A table computed and pre-sented in this article provides easy reference for the conversions and predictions needed for the various quantities at near. The table (Table 1) is computed using the logMAR scale of 1.2589 in logMAR, M and N notations. The table con-tains VA values between logMAR 1.4 (10M or 80 point) and logMAR 0.18 (1.3M or10 point) in steps of 1.2589 for reduced (non-standard) viewing distances ranging from 31.8 cm (0.32 m) to 3.2 cm (0.03M). The table contains values which can be used to convert visual acuity values measured at reduced near view-ing distances to standard visual acuity values. The values also can be used to represent any of the quantities involved in the prescription of optical devices for low vision patients. The use of the table for converting reduced distance VA values to standard values and for predict-ing optical powers and visual performance of low vision patients are discussed with relevant examples. Like all principles based on the log-MAR principles, the table is quite versatile in VA conversion and prediction of the various quantities such as print size that can be read by the low vision patient when factors such as viewing distance or power are varied.

Background: The influence of inorganic fertilizer has posed considerable challenges on increasing food production worldwide. A careful plan is required to increase the yield and quality of crops. A profound knowledge on the use of organic manure involvement in plant growth and development could be beneficial for food production. The use of acceptable inorganic and different concentrations of vermicompost has been used in an attempt to enhance crop growth and development with the aim of increasing food production. The aim of the study was to investigate the impact of vermicompost tea concentrate extracted from cow manure and grass cutting on physiological responses of tomato (Solanum lycopersicum). Vegetative growth and yield of tomato was stimulated by mineralization of organic waste coupled with the mesophilic action of earthworm. Vermicompost is a by-product of earthworm tissues. It is a nutrient source rich in essential components for plant growth and development. Methods: An investigation was conducted in pot media under exposed natural conditions from August 2020 to November 2020 at Mangosuthu University of Technology. In this experiment, the growth of tomato plants were subjected to different vermicompost concentrations and amended with NPK fertilizer were studied. Sandy loam soil of about 5 kg were weighted into pot media (2.0mheight, 2.3m diameter). The experiment was set up in a completely randomized block design consisting of five treatments with five replicates per treatment. Treatments included: Positive control (PC), 5%VCL+NPK, 10% VCL+NPK, 20%VCL+NPK and the inorganic (NPK). Result: Results revealed that there were significant differences at (P<0.01) among the treatments with respect to plant height and number of leaves from week three to week eight. Similar trends were found with 5% VCL+NPK, 10% VCL+NPK, 20% VCL+NPK and the NPK treatments. This may be due to phytohormone release from earthworm tissue. Tomato flower inflorescence was significant at (P<0.01). Tomato fruit, different components at harvest which were, weight wet and dry weight were higher with NPK treated at (P<0.01) than the 5% VCL+NPK, 10% VCL+NPK. Root length in 20% concentration was considerably higher than the other treatments. The results showed that minimum supplementation with inorganic fertiliser may be necessary with vermicompost leachate in order to successfully grow crops in nutrient deficient soil. [ABSTRACT FROM AUTHOR]

Duplication or imitation of individual keystroke rhymes is very difficult which can make it very efficient to be used for identity authentication. Over time, it is possible that the keystroke style of an individual to be learned by following keystroke information obtained when the person types text. The user's identity can always be verified by studying the user's keyboard input styles anytime the user uses the keyboard. The technique suggested in this study uses the keystrokes that users make while typing to verify their identities. To provide an accurate verification of whether a user is authentic or fraudulent, a model that integrates machine learning and dynamic keystroke models--Decision Tree, Random Forest, Support Vector Machine, and K-nearest Neighbors--is compared and utilized. The keystroke dynamics dataset was gathered from Kaggle and consists of 51 subjects' keyboard dynamics data, which was collected over the course of eight sessions and six months. There are 20400 samples in all in the data. This study assessed the effectiveness of machine learning algorithms with a focus on the keystroke dynamic authentication system. Python is used for the development work, while Jupyter notebook is used as the IDE. The performance of the models for different variables is assessed using the following metrics: accuracy, error equal rate, parameter performance, threshold, training time, and testing time. According to the results, the accuracy of the Random Forest, Support Vector Machine, KNN, and Decision Tree algorithms are, respectively, 98, 97.55, 97.28, and 94.26%. Based on the comparing results, Random Forest outperforms the other models, suggesting that Random Forest can be used as the system model for Keystroke Dynamic authentication. [ABSTRACT FROM AUTHOR]

Balanogastris kolae reduces the quality of stored kolanuts; yet, plants with insecticidal properties could be used to manage this insect pest. The objective of this study was to evaluate the efficacy of plant oils against B. kolae, a storage pest of kolanuts. The Citrus aurantifolia fruit peel and Piper guineense seed volatile oils obtained via hydro-distillation of the dried, pulverised samples were tested. Their chemical composition was determined using Gas Chromatography-Mass Spectrometry (GC-MS) analysis. Adult mortality was generally low (0.0%) across treatments and exposure times, though not significant (P > 0.05) in the fumigant tests The highest mortality (47.5%) was recorded at 24 hours in 1.0% P. guineense, while the mortality was 13.1% occurred at 12 hours in the 15.0% C. aurantifolia concentration. In contact toxicity tests, none of the weevils treated with 10.0% C. aurantifolia survived after 24 hours of exposure. The highest mortality (85.0%) was obtained from the 10.0 and 15.0% P. guineense volatile oil after 96 hours. Citrus aurantifolia elicited contact toxicity against the weevil more than P. guineense across all concentrations. The GC-MS analysis gave 33 compounds in C. aurantifolia and 43 in P. guineense volatile oil samples. The prominent compounds were limonene (3.222%), linalyl isobutyrate (2.484%), gamma-caryophyllene (1.197%) and Patchoulene (6.529%). Therefore, C. aurantifolia fruit peel and P. guineense seed volatile oils are efficacios in controlling Balanogastris kolae insect pest infestation on kolanuts, though C. aurantifolia fruit peel oil is the best as it compares closely with the synthetic pesticide (2,2-dimethyl dichlorovinyl phosphate (DDVP)). [ABSTRACT FROM AUTHOR]

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Many businesses have been positively impacted by electronic commerce (ecommerce). It has enabled enterprises and consumers transact business digitally and experience diversity as long as the internet is accessible and there is a gadget to surf the internet. Several governments have gradually adopted electronic payment throughout the country. The Nigerian government has also done a lot of prodding toward the adoption of a cashless economy, which includes embracing ecommerce. As ecommerce expands, so does actual and attempted fraud through this channel. According to the Nigerian Central Bank, electronic fraud reached trillions of Naira by 2021. The purpose of this work was to employ logistic regression as a decision-making tool for detecting fraud in e-commerce platforms at either the virtual or physical point of sale. The main contribution of this research is a model developed using logistic regression for detecting fraud at the point of sale on electronic commerce platforms. The accuracy of the result is 97.8 percent. The result of this study will provide key decision makers in ecommerce firms with information on fraud patterns on their ecommerce platforms, this will enable them take quick actions to forestall these fraudulent attempts. Further research should be carried out using data from other developing countries. [ABSTRACT FROM AUTHOR]

The emerging scenario of robust Agricultural Extension and Advisory Services (AEAS) in Africa presupposes the need for Reality Television Shows (RTS) to support AEAS demand and delivery Systems. A variant of the entertainment-education (EE) genre, RTS provides an ample platform for effective AEAS. Given this, this study investigated crop farmers’ information needs in RTS utilization in Oyo State, Nigeria. A four-stage sampling procedure was used to select 140 crop farmers who own a television set randomly, while data was collected with the use of a structured questionnaire on respondents’ characteristics, perceived benefits and constraints to utilization of RTS and information needs on farmers’ crop enterprises from RTS. Data were analyzed using frequencies, percentages, means and PPMC at P= 0.05. Findings show that respondents were predominantly male (68.6%), married (65.7%) with tertiary education (40.0%), while mean age, farming experience and annual income were 46.10±13.395years 11.36±8.83years and N464464.29±95,805.94, respectively. The likelihood of RTS to facilitate the adoption of improved technologies (4.41±3.11) and the provision of information on key factors like marketing channels and production cost (2.73±3.11) were some of the perceived benefits by respondents. However, they had reservations about the language barrier (2.3643±4.9081) as a constraint to the maximal exploitation of the potentials of RTS. Respondents’ information need was high for irrigation system (2.61±2.54), harvesting activities (1.96±0.81), and marketing outlets (3.00±2.05), across production, harvesting and marketing information needs. It is recommended that proposed RTS should use local language for RTS dissemination, while addressing the most pressing information needs of the crop farmers.

From works in in-situ seepage through dams and laboratory experiments using Layered Heterogeneous Porous Media (LHPM), it has been noted that a refraction-like phenomenon, such as that experienced in light, affects fluids' flowlines when crossing the contact interface of layers characterised by different porosity viz-a-viz permeability. This concept has many applications in fluid dynamics, such as the dispersion process in stratified media. Currently, no study exists that models and analyses the relationship between the porosities of two layers in contact and the resulting flowline refraction using validated LHPM data. Hence, this work aims to establish a relationship between the porosity ratio (Φr) of stratified media made up of two layers and the refraction angle (θmax) of the maximum volume flux (qmax). Volume flux data from the flow of a single-phase fluid through five LHPMs with Φr ranging from 0.8325 to 0.9524 were used in the modelling. The flow was oriented from the lower to the higher porosity vis-à-vis permeability layer. It was found that θmax which is also the refraction angle of the peak solute plume flux, refracts away from the normal as Φr reduces. This indicates an increase in the dilution rate vis-à-vis spread of plumes with the reduction in homogeneity between the two layers. Also, θmax does not correlate with the stratification inclination (α), but the qmax which is also the peak solute plume flux correlates with α. Furthermore, an efficient model, which is the best-unbiased estimator, with R² = 0.99 was derived. Findings from this work can help better understand solute plume dispersion and the general fluid flow dynamics in stratified media such as capillary barrier effect covers for pollution control and hydrocarbon reservoirs. [ABSTRACT FROM AUTHOR]

The desire of every broiler farmer is to produce birds with fast growth rate and good weight for both marketing and consumption. This objective can only be achieved under a good feeding regime. The physical form of the feed offered is therefore a critical factor in achieving this goal. Commercial or on-farm feed for poultry are usually presented in the form of pellets, mash or crumble feed. There exists an abundance of published data supporting the superiority of pelleted diets over mash diets. This has been variously observed in the ability of pelleted diets to improve growth rate, FCR, feed intake and dressing percentages of broilers. The quality of pellet offered constitutes a major factor in ensuring improved productivity. Although mash diet is cheaper to produce, studies have shown that it is often not too palatable to broiler birds when compared with pellets. The choice of the type of feed to be adopted therefore depends on the production objectives of the farmer and the prevailing economic conditions. Cost effective pelleting and improvement in pellet quality can therefore offer a viable means for a wholesome broiler production especially in developing countries. [ABSTRACT FROM AUTHOR]

Nigeria has recorded great losses since the outbreak of the COVID-19 pandemic in December 2019. Over-reliance on oil as source of national revenue and inadequate human capital development have impeded the country’s response to the global emergency. This study examines how technology education can stimulate a diversified economy to boost Nigeria’s capacity to withstand future crises. It employed a historical research method, comprising mainly secondary sources. The pandemic exposed the morbidity and inadequacy of Nigeria’s health facilities. In addition, a sharp drop in the global price of crude oil worsened the country’s wobbling economy during the pandemic. At the micro level, the lockdown imposed by government turned many self-employed Nigerians to idlers. The COVID-19 pandemic could have been a platform to enhance researches in medical sciences and health technology but the extant problems in the country’s higher education sector such as poor funding, lack of motivation for teaching and research, brain drain, and poor curriculum prevented meaningful innovation in that regard. The study recommends reforms in technology education to create a work force for non-oil sectors like agriculture, solid minerals, small and medium enterprises, and indigenous industries. This would stimulate self-reliance and a diversified economy to keep Nigeria unperturbed during future emergencies.

Objectives: To determine if there is any association between combined oral contraceptives (COCs) use and blood pressure (BP) change, dyslipidaemia and cardiovascular risks among COCs’ users. Design: A descriptive cohort study among 162 acceptors of COCs recruited consecutively from 2016-2020. Setting: Family planning unit of Olabisi Onabanjo University Teaching Hospital, Sagamu, Southwest, Nigeria. Subjects: Consented women who met the inclusion criteria and took up COCs as a form of family planning within the study period. Intervention: All the subjects were placed on Levofem DKT brand of combined oral contraceptive pill (levonorgestrel 0.15mg, ethinylestradiol 0.03mg, ferrous fumarate 75mg) at a dose of one tablet daily. Their blood samples were taken for fasting lipid profile (FLP) and their BP measured both at recruitment and at six months of follow-up. Outcome measures: Change in the FLP and BP within the six months of use of the COC. Data analysis was done using SPSS version 26 by IBM incorporation. Level of significance was set at P<0.05. Results: The mean age of our participants was 29.53±4.92 years. There was statistically significant association between COCs use and mean change in Total Cholesterol (t =5.263, P=0.001,), Triglyceride (t =24.974, P=0.001), Low density lipoprotein (4.974, P=0.001), high density lipoprotein (t=12.790, P=0.001) as well as the Castelli index 1 and 2 (t= 12.439, P=0.001, t=10.910, P= 0.001). However, there was no relationship between mean change in FLP and BP. Conclusion: COCs use was associated with dyslipidaemia and indirectly with cardiovascular risks. It showed no significant association with BP change. [ABSTRACT FROM AUTHOR]

Climate change has resulted in challenging environmental issues, which have become a major global concern. Farmers therefore employ several methods which are adaptable to environmental hazards. The study assessed preferences of rice farmers' coping strategies to environmental hazards in Kwara state, Nigeria. Specifically, the study, assessed frequency of occurrence of the environmental hazards faced by the rice farmers, identified the preferred coping strategies used by rice farmers and determined the effects of environmental hazards on rice production. A two-stage random sampling technique was used to select 151 rice farmers on whom an interview schedule was administered. Descriptive statistics and Pearson Product Moment Correlation were used to analyzed the data. Results showed that 94.0% of the respondents were males 45.7 mean years old, 6.6 hectares of farm size and an average of 18.7 years of farming experience, flooding, erosion and wind storm having the highest occurrence frequency in rice production. Planting of improved varieties, early planting, avoiding to plant along river borders were the most preferred coping strategies used by rice farmers. Reduction in farm output, reduction in values of farm produce, decrease of farmers' income was identified as major effects of environmental hazards on rice production. There was also a significant relationship between age (r=0.3551), household size (r=0.215), farming experience (r=0.262) and the use of preferred coping strategies. The study concluded by identifying preferred coping strategies to environmental hazard in the study area and recommends that to reduce its effect on rice production, improved rice varieties should be made available at affordable and subsidized rate by the government and relevant bodies, timely and appropriate information on weather monitoring should be available to the rice farmers through reliable and appropriate channels. [ABSTRACT FROM AUTHOR]