Extinction and persistence of a stochastic delayed Covid-19 epidemic model.

We formulated a Coronavirus (COVID-19) delay epidemic model with random perturbations, consisting of three different classes, namely the susceptible population, the infectious population, and the quarantine population. We studied the proposed problem to derive at least one unique solution in the positive feasweible region of the non-local solution. Sufficient conditions for the extinction and persistence of the proposed model are established. Our results show that the influence of Brownian motion and noise on the transmission of the epidemic is very large. We use the first-order stochastic Milstein scheme, taking into account the required delay of infected individuals.

Probabilistic analysis and simulation of crack propagation in concrete pavements and surfaces.

The surface of concrete pavement is susceptible to cracking. The propagation of a crack in a concrete structure may take the form of a one-dimensional line crack, a two-dimensional surface crack, or a three-dimensional volume crack. Predicting crack propagation in a concrete pavement surface is a complicated task. The whole process of formation, propagation, and orientation of cracks can be considered a stochastic process that necessitates a probabilistic investigation approach. In the present study, crack propagation in concrete pavements is studied from a probabilistic point of view using the concepts of multinomial Markov Chains using Random Walks. The study is based on actual probabilities of propagation and orientation of cracks obtained by tracing crack paths from a large dataset of images using custom-built software. Two random walker models are developed using the trinomial and multinomial Markov Chains. The master equation is developed assuming the trinomial Markov Chain, which has been brought for further theoretical and numerical developments. Examples of inferences and numerical simulations are presented to showcase the potential uses and applications of the proposed probabilistic approach for the design and scheduling of inspection visits and maintenance/rehabilitation strategies of concrete pavements and surfaces.

Extinction and stationary distribution of a stochastic COVID-19 epidemic model with time-delay.

We reformulate a stochastic epidemic model consisting of four human classes. We show that there exists a unique positive solution to the proposed model. The stochastic basic reproduction number R0s is established. A stationary distribution (SD) under several conditions is obtained by incorporating stochastic Lyapunov function. The extinction for the proposed disease model is obtained by using the local martingale theorem. The first order stochastic Runge-Kutta method is taken into account to depict the numerical simulations.

A stochastic SACR epidemic model for HBV transmission.

In this article, a stochastic SACR hepatitis B epidemic model is taken to be under consideration. We develop a stochastic epidemic model by considering the effect of environmental fluctuation on the hepatitis B dynamics and distribute the transmission rate by white noise. Using the stochastic Lyapunov function theory, we have shown the existence and uniqueness of the global positive solution. The extinction and persistence for our proposed model are derived with sufficient conditions. The numerical simulations are carried out using first-order Itô-Taylor stochastic scheme in the last section for the verification of our theoretical results.

Dataset in the characterization of black spot Ehrenberg snapper and its proteins' denaturation inhibition by natural antioxidants.

The data represented in this paper describe techniques, methodologies and data obtained during the biochemical composition characterization of Blackspot Snapper (Ehrenberg's Snapper). Data analysis of protein, lipids, moisture, ash contents of Ehrenberg's snapper, total polyphenols, total flavonoids contents and the DPPH scavenging activities of Cinnamon (Cinnamomum verum J. Presl) bark (50 mg/50 g), cumin (Cuminum cyminum L.) (50 mg/50 g), turmeric (Turmerica longa L.) (50 mg/50 g), garlic (Allium sativum L.) (50 mg/50 g), ginger (Zingiber officinale Roscoe) (50 mg/50 g) and Vitamin C (25 mg/50 g) are represented. Data obtained from the Infrared spectroscopy (FTIR) analysis of the six spices and vitamin C treated and stored fillets at -25 °C, namely three vibrations, Amide A, NH stretching at 3300 cm-1; Amide I, C=O stretching 1600-1690 cm-1 and Amide II, CN stretching and NH bending at 1480-1575 cm-1. Differential scanning calorimetry (DSC) analysis data of three main denaturations; myosin, actin and sarcoplasmic proteins are presented.

The Effects of Storage on Quality and Nutritional Values of Ehrenberg's Snapper Muscles (Lutjanus Ehrenbergi): Evaluation of Natural Antioxidants Effect on the Denaturation of Proteins.

: Protein denaturation in frozen minced fillets (Ehrenberg's Snapper), stored at -25°C was studied; 50.0 mg biomass/50g mince fillets treated with cinnamon, cumin, turmeric, garlic, ginger and 25.0 mg of vitamin C were used to slow protein denaturation. FT-IR stretching vibration of Amide-A (νNH) at 3300 cm-1; Amide-I stretching (νC=O) between 1600-1690 cm-1 and Amide-II stretching (νCN) and bending (δNH) between 1480 and 1575cm-1 were used as marker peaks. Garlic was the most significant (P ≤0.01) in controlling the rate of protein denaturation when νNH was used as a marker peak. DSC analysis showed that turmeric presented the highest effect on delaying the denaturation of sarcoplasmic proteins with a ∆H0=73.7J/g followed by garlic-treated mince fillets ∆H0=70.1J/g. All spices used were efficient in stopping the denaturation of myosin with the highest ∆H0=769.3 J/g registered for cinnamon-treated mince fillets. Actin was less vulnerable to denaturation in comparison to myosin and sarcoplasmic proteins.

On both magnetized and non-magnetized dual stratified medium via stream lines topologies: A generalized formulation.

The major concern of current pagination is to report the doubly stratified medium subject to both magnetized and non-magnetized flow fields. For this purpose both the Newtonian and non-Newtonian liquids are considered in a double stratified medium having magnetic field interaction. To be more specific, a generally accepted rheological liquid around a cylindrical surface having constant radius embedded in magnetized doubly stratified media is taken into account. Additionally, flow field is manifested with various pertinent physical effects. The flow problem statement is defended through generalized formulation via fundamental laws. A computational scheme is executed and stream lines topologies are constructed for the both magnetized and non-magnetized stratified medium to explore the interesting features. It is observed that the Casson fluid velocity towards cylindrical surface is higher in magnitude as compared to flat surface. Such observation is same for the both the magnetized and non-magnetized flow fields. Our general formulation yields some existing attempts in the literature. The variations in local skin friction coefficient (LSFC), local Nusselt number (LNN) and local Sherwood number (LSN) are provided with the aid of tabular forms. It is trusted that the obtain observations via stream lines topologies will serve a clear insight to the said flow problem.