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This paper investigates the dynamics of market synchronicity and International Financial Reporting Standards (IFRS) adoption in Africa. It seeks to determine whether or not IFRS is an augmentor or inhibitor of market synchronicity in Africa. This study is not only a foundational study that unfolds the dynamics of market synchronicity and IFRS adoption in Africa but also extends the scope of synchronicity from firm-level assessment to country-level market synchronicity. It is one of the few studies which have shifted the literature on synchronicity from one largely limited to firm-level synchronicity to country-level synchronicity through analyses of cross-border market synchronisation. It employs Dynamic Ordinary Least Square (DOLS) and Generalised Method of Moments (GMM) to investigate the market synchronicity-IFRS nexus. The study uses monthly data from March 2005 to November 2021 in five African markets: Botswana, Ghana, Namibia, Nigeria, and South Africa generating 1005 observations in an 18-year data span. The paper reveals a significant negative consequence of IFRS on market synchronicity. Thus, IFRS exhibits an inhibition role in market synchronicity (reduces synchronicity) and improves price informativeness. A decreasing pattern was also observed immediately after IFRS was adopted by the stock markets and persisted for about five years. It implies that the price informativeness of stock markets through IFRS makes them good candidates for intra-Africa portfolio diversification due to reduced investors’ risk exposure to market synchronicity.

Measles is a highly communicable viral infection that mostly affects children aged 5 years and below. Maternal antibodies in neonates help protect them from infectious diseases, including measles. However, maternal antibodies disappear a few months after birth, necessitating vaccination against measles. A mathematical model of measles, incorporating maternal antibodies and a double-dose vaccination, was proposed. Whenever ℛ0

This study delves into the often‐overlooked impact of immature mosquitoes on the dynamics of malaria transmission. By employing a mathematical model, we explore how these aquatic stages of the vector shape the spread of the disease. Our analytical findings are corroborated through numerical simulations conducted using the Runge–Kutta fourth‐order method in MATLAB. Our research highlights a critical factor in malaria epidemiology: the basic reproduction number R0. We demonstrate that when R0 is below unity R0<1, the disease‐free equilibrium exhibits local asymptotic stability. Conversely, when R0 surpasses unity R0>1, the disease‐free equilibrium becomes unstable, potentially resulting in sustained malaria transmission. Furthermore, our analysis covers equilibrium points, stability assessments, bifurcation phenomena, and sensitivity analyses. These insights shed light on essential aspects of malaria control strategies, offering valuable guidance for effective intervention measures. [ABSTRACT FROM AUTHOR]

In this study, a nonlinear dynamic SEVIQR measles epidemic model is constructed and analyzed using the novel Caputo fractional‐order derivative operator. The model's existence and uniqueness are established. In addition, the model equilibria are determined, and the novel Jacobian determinant method recently constructed in the literature of epidemiological modeling of infectious diseases is applied to determine the threshold quantity, R0. Furthermore, we construct appropriate Lyapunov functions to establish the global asymptotic stability of the disease‐free and endemic equilibrium points. Finally, the numerical solution of the model is executed employing the efficient and widely known Adams‐type predictor‐corrector iterative scheme, and simulation is conducted to investigate the impact of memory index and diverse preventive measures on the occurrence of the disease. Numerical simulation of the model indicates that quarantine, vaccination, and treatment can reduce the numbers of infectious and exposed populations, thereby controlling the disease. Therefore, it is recommended that the government provide financial assistance for vaccine distribution. [ABSTRACT FROM AUTHOR]

Malaria is an old, curable vector‐borne disease that is devastating in the tropics and subtropical regions of the world. The disease has unmatched complications in the human host, especially in children. Mathematical models of infectious diseases have been the steering wheel, driving scientists towards elucidation of the dynamic behaviour of epidemics and providing tailored strategic management of diseases. With the ongoing vaccination programs for vector‐borne diseases, the research proposes a nonlinear differential equation model for the malaria disease that provides public health with a shift from the classical understanding of nonpharmaceutical preventive malaria control to pharmaceutical measures of vaccines. The asymptotic dynamic behaviour of the model is studied at the model's equilibria. The bifurcation type invoked at the disease‐free state is analysed, and the result revealed that the convention that R0<1 is the condition for eradicating the disease is not always sufficient when the system undergoes backward bifurcation. Furthermore, sensitivity analysis was investigated to quantify the amount of influence each parameter has on R0. With the Latin hypercube sampling and partial rank correlation coefficient method, the uncertainty in R0 is computed with a 95% confidence interval, with the mean, and 5th and 95th percentiles, respectively, simulated as 0.143788, 0.01545, and 0.41491. An intervention model was derived from the nonintervention model to experiment with and evaluate the respective effects of the various pairings of interventions on the dynamics of the disease. Lastly, an in‐depth cost analysis was studied to identify the most cost‐effective intervention regarding rewarding the desired outcome. From the analysis, we recommend that besides the nonpharmaceutical measure of bed nets and insecticide spray, public health should target the pharmaceutical intervention of vaccine as it can close the gap in malaria prevention. [ABSTRACT FROM AUTHOR]

Human immunodeficiency virus (HIV) and tuberculosis (TB) have long been known to have a synergistic relationship. This is a result of each of the diseases impacting negatively on the immune system of the infected persons. The impact of these diseases on workforce productivity is studied in this paper from the viewpoint of dynamical systems. In this paper, we present a nonlinear ordinary differential equation model to study the dynamics of HIV-TB co-infection and its effect on workforce productivity. The main model is first decoupled into two basic submodels of HIV-only and TB-only models, whose qualitative properties are presented before the qualitative properties of the main model are studied. While the HIV-only model is shown to have a globally asymptotically stable disease-free equilibrium whenever its basic reproduction number is less than unity, the TB-only model is shown to exhibit backward bifurcation under some conditions. To investigate the impact of various intervention strategies on the control of the co-infection and improvement of workforce productivity, five time-dependent controls (involving transmission prevention for the two diseases, therapy for the two diseases, and capacity building for improved workforce productivity) are incorporated into the basic model to form an optimal control problem, which is qualitatively analyzed using Pontryagin's maximum principle and numerically simulated. Incremental cost-effectiveness analysis is conducted with the results of the numerical simulations. It is observed that the most cost-effective strategy for fighting the spread of the co-infection with enhanced productivity is that of combining both preventative and curative measures along with skills training. [ABSTRACT FROM AUTHOR]

A deterministic model is developed to study the dynamics of poliomyelitis virus infection with vaccination in a population with insanitary conditions. The polio-free equilibrium is shown to be locally asymptotically stable whenever the basic reproduction number is less than one but global stability requires other conditions to be satisfied. The spread of the disease is also shown to be sensitive to the average contact rate with the faecal matter of the infectious individuals, the transmission probability, natural death rate and vaccination, probabilities of the exposed individuals progressing to the non-paralytic and paralytic classes, the open defecation parameter and the polio-induced death rate. Other interesting results are illustrated through numerical simulation of the model. [ABSTRACT FROM AUTHOR]

This research examines the effects of moving loads on viscously damped axial force Rayleigh beam. The authors especially tried to find the effect of the moving mass and moving force in connection with the length of the span of a Rayleigh beam. The authors also examined the effect of the lengths of the beam and of the load. It was observed that as mass of the moving load increases the deflection along the length of the beam also increases. It was further observed that the deflection of the moving mass is greater than that of the moving force. Key words: Viscously damped, axial force, rayleigh beam, moving force and moving mass, INTRODUCTION From historical viewpoint, the problem of moving load back to the beginning of the nineteenth century, the time of erection of the early railway bridges. A lot of work [...]