Lassa fever is a zoonotic viral illness that is endemic in West Africa. The disease has been a subject of intensive research in the mathematics and non-mathematics fields after the first case was confirmed in Nigeria in 1969. Treatment is inevitable after the full incubation of a disease but there may not be a total compliance to treatment guidelines due to factors like poverty and ignorance especially in poor communities. These factors can seriously affect the dynamics of Lassa fever but have not been paid attentions to in the literature. Based on this, a stage of infection when the disease has been fully incubated is considered and a new mathematical model is designed to examine the effect of treatment compliance on the dynamics and control of Lassa fever. The model validity was examined and established using ample mathematics theorems. The equilibria and a threshold for disease eradication were derived. The stability was analyzed and the necessary and sufficient conditions for the equilibria of the model to be stable both locally and globally were derived. Further, sensitivity analysis was carried out to investigate the relative contributions of various parameters to Lassa fever spread and management. Numerical simulation was later conducted via a logical parameter values from the literature to visualize the effect of parameters perturbations on the dynamics of the disease. Results from the study revealed that Lassa fever eradication is a function of total compliance to treatment procedures.

In this study, a two‐phase lattice Boltzmann model (LBM) is developed and verified to study natural convective heat transfer in a porous medium that is fully saturated with Zn–H2O nanofluid (NF). Zinc, being an environmentally friendly material, is selected as the nanoparticle (NP) here. We aim to analyze NP heat enhancement augmentation and dispersion during NF transport at different Rayleigh number (Ra) values, various porosity ( ε ), and varying nanoparticle volume fraction (NVF). The equations of flow (velocity), temperature (energy), and NVF fields in porous media are solved numerically. Physical parameters of Rayleigh number, NVF, and Darcy number (Da) are varied to examine their effects on flow patterns (streamlines), temperature distribution (Isotherms), and NP spread (dispersion). Nusselt number is calculated to elucidate its relationship with Ra, Da, and NVF. Results show that Nusselt number increases upon Ra and Da numbers increment thereby accounting for convective heat transfer augmentation. However, it is noted that at Ra = 105; ε = 0.4   and   0.9 , the effects of varying NVF are almost the same, thereby suggesting an optimum for positive NP effect. An improved NP dispersion leading to good suspension stability for optimum Zn NP performance is observed with a higher temperature gradient at Ra = 10 5 , Da = 10 − 2 compared to Da = 10 − 4 , where NP sedimentation is noticed. Likewise, an increase of NVF suggests an increase in Nusselt number until a certain optimum. This study provides deeper insight into NP dynamics and their heat transfer behavior in porous media using LBM.

As COVID-19 continues to spread across the globe, governments all over the world have been finding ways of mitigating the pandemic. Various measures including lockdown and social distancing have been enacted to curb the spread of the virus. While the epidemiological trends of the disease have received considerable attention, the economic impacts of the outbreak on the households have been largely understudied. A compartmental model was developed and an epidemiological modelling approach was adopted to examine the economic impact of lockdown and social distancing on Nigerian households. The basic epidemiological features of the model were examined before the model was studied analytically and numerically. Both the analytical and numerical results showed that the economies of every household in Nigeria apart from the rich was badly affected by the mitigation measures of COVID-19 when there was an impediment to the payment of salaries and distribution of palliatives.

Graphene and its derivatives have been a promising material in all area of science and technology for many decades. In the recent years, its outlooks and applications in oil and gas upstream industry are of a major importance. As a result of its exceptional chemical, electrical, structural, and mechanical properties, it can act as a good agent for the recovery of trapped oil. The aim of this review was to provide insight on application of graphene nanoparticles in upstream industries. Furthermore, the advances of graphene synthesis techniques and its impacts on oil mobility ratio in enhancing oil recovery process were analyzed. Extensively, the mechanism of oil recovery enhancement using graphene nanoparticles were discussed. Graphene nanoparticles shows a positive impact on both rheological and stabilization characteristics of drilling fluids, wettability alteration, interfacial tension, and improving the emulsion stability. The challenges of graphene nanoparticles in enhance oil recovery are explained and its solution.

The advancement of nanotechnology has contributed immensely in solving major problems in engineering and medical applications. Versatility of nanofluids made of nanoparticles is attributed mainly to the size, shape, type and ionic composition of the particles. Specifically, the use of nanofluids for heat augmentation and mass transport is of wide application and it is accruing interest from researchers. Nonetheless, experimental approach may be cumbersome and expensive. To this end, Lattice Boltzmann method (LBM) has shown its capability in the study of complex flow systems that have complicated geometries (e.g. porous media) with acceptable accuracy while using a simple algorithm. In this review, we present a rich summary of the latest findings on the application of LBM fornanofluids related heat and mass transfer processes with emphasis on porous media and also highlight current challenges for future research.

In this work, the influence of entropy generation analysis for an electrically conducting Casson fluid flow with convective boundary conditions has been numerically studied. The governing equations are analyzed numerically using weighted residual methods. Subsequently, the residuals were minimized using two different approaches of weighted residual method namely collocation weighted residual method (CWRM) and Galerkin weighted residual method (GWRM) and computed numerically using MATHEMATICAL software. The impacts of governing parameters on Casson flow velocity, temperature profile, local skin friction, and Nusselt number were analysed. The obtained solutions were used to determine the heat transfer irreversibility and bejan number of the model. The results of the computation show that the effect of thermophysical properties such as thermal radiation parameter, suction/injection parameter, magnetic field parameter, radiation parameter, and Eckert number has a significant influence on Skin friction coefficient (Cf) and local Nusselt number (Nu) when compared to the Newtonian fluid. The findings from this study are relevant to advances in viscoelasticity and enhanced oil recovery.

The urgency in demand for global warming alleviation has necessitated more research into carbon-dioxide diffusion (CO2) both for sequestration and enhanced oil recovery. Captured atmospheric CO2 can be stored underground to leave a haven for the populace. CO2 diffusivity in oil-brine-rock systems at various pressures and temperatures and also solely in brine with different ions but at a fixed temperature and pressure are studied. Increases in pressure and temperature leads to increase in diffusion coefficient of CO2 in oil-brine-rock systems. On the other hand, in CO2-brine system, the variations of ions affect CO2 diffusion while Ca ion appears to result in the highest diffusivity of CO2 in brine thereby, suggesting saline aquifers with Ca ion as the best choice for CO2 sequestration.

This study presents the viabilities for power generation in Nigeria through the utilization of the sun's energy. Solar-thermal and photovoltaic options were discussed. It highlights the basic science for the design and selection of com- ponents for successfully harnessing solar power. Requirements for solar panel placement and orientation were also high- lighted. It emphasizes that the knowledge and experience gained in solar energy as an abundant and convenient energy source, can play a role in steering the nation toward a permanent and sustainable development. The energy demand in Nigeria far outweighs the supply which is epileptic in nature. The acute electricity supply hinders the country's develop- ment notwithstanding the availability of vast natural resources in the country. Our ability to continue the trend for afford- able energy will be severely tested in the coming decades, as evidenced by the widening trade imbalance, collapse of big manufacturing companies, sharp increase in the cost of doing business just to mention but a few. It is the issue of utilizing the sun's silent, inexhaustible, and non-polluting resource for power generation in Nigeria that this work addresses; hence it is the long-range review of the energy problem.