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The purpose of this paper is to focus on the antioxidant properties of two phenolic-rich varieties of Nigerian local rice and their anti-cholinesterase potential after in vitro-simulated gastrointestinal digestion, with the aim of establishing their actual antioxidant and nutraceutical potential after their passage through the gastrointestinal tract upon consumption.

Two local rice varieties, commonly referred to as “Gboko” and “Ofada” rice commonly grown in Benue State, a middle belt region of Nigeria and south western regions of Nigeria, respectively, were locally processed. Each of the processed grains were divided into two portions; one portion was left uncooked, while the second portion was boiled conventionally as eaten, dried and subsequently milled into powder. The milled samples of the raw and boiled rice were treated with acidified methanol to obtain the methanol extracts; another portion of each samples was subjected to in vitro enzyme digestion using standard methods to mimic human digestion; and the third portion was treated using the same scheme of in vitro digestion without the sets of enzyme which was used to serve as a control for enzyme treatment. The quali-quantitative phenolic profiles of the two local varieties were carried out with the aid of high-performance liquid chromatography with diode-array detection (HPLC-DAD) method. The antioxidant potential and anti-cholinesterase action of the methanolic extracts, the simulated in vitro digested model and the enzyme-treated controls of the rice samples were determined using standard methods and data obtained were subjected to ANOVA; the differences of means were separated using Duncan’s multiple range test (DMRT).

The quali-quantitative assessment of phenolic compounds in the two studied local varieties revealed the presence of some phenolic acids and flavonoids, with a decreased level of most of the identified phenolic compounds after boiling. In vitro enzyme-digested rice for both raw and boiled rice samples showed significantly higher total phenolic content, total flavonoid content, ferric-reducing antioxidant power, 2, 2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS+) scavenging and NO− inhibitory activities than the aqueous-methanolic extracts and the enzyme-treated controls. The aqueous-methanolic extracts displayed a higher 1, 1 diphenyl-2-picrylhdrazyl radical scavenging activity and inhibited Fe2+-induced lipid oxidation in rat’s brain and liver homogenate than that displayed by the in vitro enzyme-digested samples. In vitro enzyme-digested and boiled “Gboko” and “Ofada” rice and raw “Ofada” rice have the potential of inhibiting acetylcholine esterase (AChE) activity. While methanolic extracts of raw and boiled “Ofada” and “Gboko” rice exhibited the potential to inhibit butrylcholinesterase activity. The result of this paper indicates that the selected rice varieties possess antioxidant capacities which are better released after the simulated in vitro enzyme digestion; the result also showed the anti-cholinesterase potential of the studied rice grains and, therefore, they can be considered as nutraceutical health supplements.

The paper has demonstrated the antioxidant potentials of the phenolic-containing two Nigerian local rice varieties and established their anti-cholinesterase potential after simulated in vitro enzyme digestion.

This paper aims to analyze heat and mass transfer of magnetohydrodynamic (MHD) non-Newtonian fluids flow past an inclined thermally stratified porous plate using a numerical approach.

The flow equations are set up with the non-linear free convective term, thermal radiation, nanofluids and Soret–Dufour effects. Thus, the non-linear partial differential equations of the flow analysis were simplified by using similarity transformation to obtain non-linear coupled equations. The set of simplified equations are solved by using the spectral homotopy analysis method (SHAM) and the spectral relaxation method (SRM). SHAM uses the approach of Chebyshev pseudospectral alongside the homotopy analysis. The SRM uses the concept of Gauss-Seidel techniques to the linear system of equations.

Findings revealed that a large value of the non-linear convective parameters for both temperature and concentration increases the velocity profile. A large value of the Williamson term is detected to elevate the velocity plot, whereas the Casson parameter degenerates the velocity profile. The thermal radiation was found to elevate both velocity and temperature as its value increases. The imposed magnetic field was found to slow down the fluid velocity by originating the Lorentz force.

The novelty of this paper is to explore the heat and mass transfer effects on MHD non-Newtonian fluids flow through an inclined thermally-stratified porous medium. The model is formulated in an inclined plate and embedded in a thermally-stratified porous medium which to the best of the knowledge has not been explored before in literature. Two elegance spectral numerical techniques have been used in solving the modeled equations. Both SRM and SHAM were found to be accurate.

This paper aims to determine the challenges and prospects for affordable housing within the context of sustainability by investigating the socio-economic and environmental impacts of housing developments based on the analysis of four so-called affordable housing schemes in Yola, Nigeria. Using questionnaire survey and indicators developed from literature reviews on affordable and sustainable housing, the findings suggest that due to inadequate availability of housing inputs (land, finance, infrastructure, labor and materials), lack of diversity, improper location, inefficient transport facilities and lack of user participation, the examined developments are neither sustainable nor affordable. The research hence contributes some empirical evidence to overcome the defined shortcomings and provides a basis for governments' housing commitments towards reforming and devising policies for community involvement in housing provision, providing easy access to land with legal title deeds, easy access to housing finance, infrastructure, etc.

This study investigates the determinants of the cash conversion cycle (CCC in the Middle East and North Africa (MENA) countries).

Using the data of 395 companies from 10 countries in the MENA region for six years (2013–2018), the authors run dynamic panel regressions. The authors developed several models to examine the determinants of CCC and its components. The models included several control variables: firm, industry and country characteristics.

The results reveal that firm characteristics (e.g. operating cash flow, sales growth rate, operating profit margin, firm size and tangibility) affect CCC. The model in which CCC is a dependent variable produced more significant results than those which the components of CCC were dependent variables.

The findings suggest that corporate managers when making their working capital management decisions should pay equal attention to the components of CCC and develop a comprehensive working capital management policy.

To the best of the authors’ knowledge, this is the first study to examine determinants of CCC in the MENA context in both country and industry details.

The failure and abandonment of construction projects have proven to be insurmountable problems incessantly militating against the efficient performance of the construction industry in Nigeria. The complexity, technicality and a host of other project execution issues unique to multi-storey building projects do increase their susceptibility to failure and abandonment. Thus, the purpose of this paper is to examine the factors influencing failure and abandonment of multi-storey building projects in Nigeria. This is with a view to provide inferential empirical data that could enhance successful delivery of multi-storey building projects in Nigeria.

Primary data were used for the study. A structured questionnaire was administered on consultants and contractors’ personnel within Lagos State, Nigeria. A total of 180 copies of the questionnaire were administered ,and 134 copies which represent a combined response rate of 74.4 per cent were retrieved. The data were analysed using frequency distribution and percentages, Mean item score and factor analysis.

The factors most significant to the failure and abandonment of multi-storey building projects are inadequate funding by the client, improper planning at the pre-construction phase, structural failure in multi-storey building during construction, bankruptcy/business failure of the contractor, improper scheduling of the building project activities and failure to engage qualified professionals with technical expertise and experience. The rated factors clustered under human resources capability, planning and structural quality, contractor selection and variation, insecurity and variation, and force majeure and political risk.

The study was limited to multi-storey building projects in Lagos State, Nigeria. Further studies could focus on specific resuscitation strategies for abandoned multi-storey building projects.

The study provided implications for effective project and contract management of multi-storey building projects which is very paramount to improve the delivery of complex, technical- and capital-intensive building projects in Nigeria.

The study provides specific implications for the management of multi-storey building projects, thereby enhancing the delivery of building projects.

The purpose of this paper was to examine the attitudes of prison inmates and warders (prison staff) to rehabilitative counselling and its relationship to their prison status on one hand and their educational attainment on the other.

The study adopts a descriptive survey research design. In all 123 prison inmates and 110 warders were selected by stratified random sampling from Osogbo prison headquarters, as well as Ilesa and Ile-Ife prisons in southwestern Nigeria. Data were collected through a self-constructed questionnaire titled “inmate and prison staff attitude to rehabilitation counselling”. Data collected were analysed using percentages and χ2 statistics.

The results showed that the prison inmates and staff possessed positive attitude to rehabilitative counselling. No significant difference was found between the attitudes of prison inmates and staff members or on the basis of their prison statuses. However, the study found a significant relationship between the prison inmates’ attitude to rehabilitative counselling and their educational attainment.

Statutory provision needs be made for professional rehabilitative counselling in Nigerian prisons in contrast to the religious instructions currently being allowed prisoners. Educational opportunities should be provided to ensure that the knowledge so obtained complements the rehabilitative counselling.

This paper fulfils an identified need to study the attitude towards rehabilitative counselling.

The purpose of this study is to examine the flow and heat transfer performance of titanium oxide/water and copper/water nanofluids with varying nanoparticle morphologies by considering magnetic, Joule heating and viscous dissipation effects. Furthermore, it studies the irreversibility caused by the flow of a hydromagnetic nanofluid past a radiated stretching sheet by considering different shapes of TiO₂ and Cu nanoparticles with water as the base fluid.

In this study, the authors investigated entropy production in an unsteady two-dimensional magneto-hydrodynamic nanofluid regime using water as the base fluid and five unique TiO₂ and Cu nanoparticle morphologies. Using appropriate similarity transformations, the controlling nonlinear system of partial differential equations is transformed into a system of ordinary differential equations. The shooting technique with Runge–Kutta method was then used to solve these equations quantitatively. The findings of this study are depicted graphically, and the skin friction corresponding to various nanoparticle geometries and physical parameter variations is tabulated.

To assess the reliability of the current findings, a tabular representation of the data was compared to that of previously published studies. It is noted that a reduction in thermal energy was detected as a result of the higher levels of Prandtl number (Pr). It is further analysed that the highest heat energy generation of TiO₂ nanoparticles was larger than that of Cu nanoparticles. The most important finding was that the sphere-shaped Cu/H₂O nanofluid had the lowest velocity and greatest temperature. Also, Cu nanoparticles in the shape of platelets generate the most entropy, while TiO₂ nanoparticles in the shape of spheres generate the least.

To the best of the knowledge of the authors, the attempt to investigate the previously unexplored shape effects of TiO₂ and Cu nanoparticles on the heat transfer enhancement and inherent irreversibility caused by hydromagnetic nanofluid flow past a radiated stretching sheet with magnetic, Joule heating and viscous dissipation effects. This study fills this gap in the existing literature and encourages scientists, engineers and businesses to do more research in this area. This model can be used to improve heat transfer in systems that use renewable energy, thermal management in industry and the processing of materials.

With the development of financial technology (FinTech), this paper aims to investigate the association between mobile payment use and payment satisfaction using data from the 2017 China Household Finance Survey (CHFS).

This study uses ordered probit regressions to examine the association between mobile payments and payment satisfaction because the dependent variable is ordinal. To alleviate endogeneity problems, this study uses instrument variables and Heckman's two-step estimation. Furthermore, to explore the potential mediators in this process, this study follows the three steps suggested by Baron and Kenny (1986). Finally, this study divides the whole sample into subsamples to examine whether the association between mobile payments and payment satisfaction differs in diverse groups.

The results indicate that mobile payment use is positively associated with payment satisfaction. Moreover, mediation analyses imply that mobile payment use may help increase consumers' credit availability, which eventually improves payment satisfaction. Three moderators of this association are financial literacy, expenditure level and portfolio diversification, which enhance the positive association between mobile payment use and payment satisfaction.

This study explores the potential mediators between mobile payment use and payment satisfaction, which is beneficial to comprehensively understanding various pathways of this process. Moreover, this study conducts heterogeneous analyses to investigate whether associations between mobile payments and payment satisfaction are moderated by various factors, which will allow policymakers to formulate policies appropriate for specific situations of diverse consumer groups.

The continuous failure of construction projects notwithstanding appreciable increase in project management knowledge has necessitated a proactive approach of assessing early warning signs (EWS) of building projects failure. Building projects are expected to show warning signs before experiencing crises, comparable to a patient displaying symptoms of a disease. Thus, this study aims to examine the EWS that predisposed building projects to failure in Nigeria to provide empirical data for enhancing projects delivery.

Primary data were used for the study. Structured questionnaire was administered to consultants and contractors’ personnel within Lagos State, Nigeria. A total of 180 copies of questionnaire were administered and 134 copies (combined response rate of 74.44 per cent) were retrieved. Frequency distribution, percentages, mean item score and Mann–Whitney test were used to analyse the data.

Most construction professionals applied the EWS approach from project planning and early construction phase. The most significant EWS predisposing building projects to failure were “Management inability and incompetence to proactively detect and manage problems at early project stages”, “Actual expenditure is constantly shooting beyond cost estimates” and “Incurred costs already getting higher than the anticipated benefits”. Project/construction management-related symptoms are most significant to predisposing building projects to failure.

The study provided implications for effective project management of building projects through proactive approach which is very paramount to improving the delivery of building projects in Nigeria.

The study provides implications for proactive management of building projects, thereby enhancing the delivery of building projects.

This paper aims to address the problem of double-diffusive magnetohydrodynamics (MHD) non-Darcy convective flow of heat and mass transfer over a stretching sheet embedded in a thermally-stratified porous medium. The controlling parameters such as chemical reaction parameter, permeability parameter, etc., are extensively discussed and illustrated in this paper.

With the help of appropriate similarity variables, the governing partial differential equations are converted into ordinary differential equations. The transformed equations are solved using the spectral homotopy analysis method (SHAM). SHAM is a numerical method, which uses Chebyshev pseudospectral and homotopy analysis method in solving science and engineering problems.

The effects of all controlling parameters are presented using graphical representations. The results revealed that the applied magnetic field in the transverse direction to the flow gives rise to a resistive force called Lorentz. This force tends to reduce the flow of an electrically conducting fluid in the problem of heat and mass transfer. As a result, the fluid velocity reduces in the boundary layer. Also, the suction increases the velocity, temperature, and concentration of the fluid, respectively. The present results can be used in complex problems dealing with double-diffusive MHD non-Darcy convective flow of heat and mass transfer.

The uniqueness of this paper is the examination of double-diffusive MHD non-Darcy convective flow of heat and mass transfer. It is considered over a stretching sheet embedded in a thermally-stratified porous medium. To the best of the knowledge, a problem of this type has not been considered in the past. A novel method called SHAM is used to solve this modelled problem. The novelty of this method is its accuracy and fastness in computation.