On stability of the third order partial delay differential equation with involution and Dirichlet condition

In this paper the stability of the initial value problem for the third order partial delay differential equation with involution is investigated. The first order of accuracy absolute stable difference scheme for the solution of the differential problem is presented. Stability estimates for the solution of this difference scheme are proved. Numerical results are provided

Evaluation of cytotoxicity and oxidative DNA damaging effects of di(2-ethylhexyl)-phthalate (DEHP) and mono(2-ethylhexyl)-phthalate (MEHP) on MA-10 Leydig cells and protection by selenium

Di(2-ethylhexyl)-phthalate (DEHP) is the most abundantly used phthalate derivative, inevitable environmental exposure of which is suspected to contribute to the increasing incidence of testicular dysgenesis syndrome in humans. Oxidative stress and mitochondrial dysfunction in germ cells are suggested to contribute to phthalate-induced disruption of spermatogenesis in rodents, and Leydig cells are one of the main targets of phthalates' testicular toxicity. Selenium is known to be involved in the modulation of intracellular redox equilibrium, and plays a critical role in testis, sperm, and reproduction. This study was aimed to investigate the oxidative stress potential of DEHP and its consequences in testicular cells, and examine the possible protective effects of selenium using the MA-10 mouse Leydig tumor cell line as a model. In the presence and absence of selenium compounds [30. nM sodium selenite (SS), and 10 μM selenomethionine (SM)], the effects of exposure to DEHP and its main metabolite mono(2-ethylhexyl)-phthalate (MEHP) on the cell viability, enzymatic and non-enzymatic antioxidant status, ROS production, p53 expression, and DNA damage by alkaline Comet assay were investigated. The overall results of this study demonstrated the cytotoxicity and genotoxicity potential of DEHP, where MEHP was found to be more potent than the parent compound. SS and SM produced almost the same level of protection against antioxidant status modifying effects, ROS and p53 inducing potentials, and DNA damaging effects of the two phthalate derivatives. It was thus shown that DEHP produced oxidative stress in MA-10 cells, and selenium supplementation appeared to be an effective redox regulator in the experimental conditions used in this study, emphasizing the critical importance of the appropriate selenium status. © 2010 Elsevier Inc

Relative bioavailability study of a generic effervescent tablet formulation of dexketoprofen and thiocolchicoside versus the originator 25 mg film coated tablet (dexketoprofen) and 8 mg capsule (thiocolchicoside)

Aims: The aim of this study was to evaluate the pharmacokinetic profiles and the relative bioavailability of dexketoprofen and thiocolchicoside of the test preparation (dexketoprofen / thiocolchicoside 25 mg / 8 mg effervescent tablet) in comparison with the reference preparations (Keral 25 mg film coated tablet, containing dexketoprofen trometamol equivalent to 25 mg dexketoprofen (Menarini International Operations Luxembourg S.A.) (R1) and Muscoril 8 mg capsule, containing 8 mg thiocolchicoside (Sanofi Aventis İlaçları Ltd. Şti.) (R2) under fasting conditions. Methods: 25 healthy male subjects were enrolled in the study. Volunteers were hospitalised from the evening before drug administration (Day 0) until after the 24-hour blood sampling time on Day 2. Results: 24 subjects completed the study. Relative bioavailability (AUCT/AUCR1) of dexketoprofen from the test preparation was 100.99 %; (AUCT/AUCR2) of 3-O-glucuronide of thiocolchicoside (aglycone) from the test preparation was 100.47 %; (Cmax,T/Cmax,R1) of dexketoprofen from the test preparation was 122.59 %; (Cmax,T/Cmax,R2) of 3-O-glucuronide of thiocolchicoside (aglycone) from the test preparation was 111.43 %. Conclusions: The relative bioavailability AUCT /AUCR of the test preparation compared with both reference preparations is comparable, as shown by the geometric mean ratios of 100.59 % (dexketoprofen) and of 98.20 % (3-O-glucuronide of thiocolchicoside (aglycone)

Transmission dynamics and control strategies of COVID-19: a modelling study

In this paper a mathematical model is proposed, which incorporates quarantine and hospitalization to assess the community impact of social distancing and face mask among the susceptible population. The model parameters are estimated and fitted to the model with the use of laboratory confirmed COVID-19 cases in Turkey from March 11 to October 10, 2020. The partial rank correlation coefficient is employed to perform sensitivity analysis of the model, with basic reproduction number and infection attack rate as response functions. Results from the sensitivity analysis reveal that the most essential parameters for effective control of COVID-19 infection are recovery rate from quarantine individuals (δ1), recovery rate from hospitalized individuals (δ4), and transmission rate (β). Some simulation results are obtained with the aid of mesh plots with respect to the basic reproductive number as a function of two different biological parameters randomly chosen from the model. Finally, numerical simulations on the dynamics of the model highlighted that infections from the compartments of each state variables decreases with time which causes an increase in susceptible individuals. This implies that avoiding contact with infected individuals by means of adequate awareness of social distancing and wearing face mask are vital to prevent or reduce the spread of COVID-19 infection

Numerical solutions of the system of partial differential equations for observing epidemic models

In the present paper, stability of initial-boundary value problem for the system of partial differential equations for observing HIV mother to child transmission epidemic models is studied. Applying operator approach, theorems on stability of this problem and of difference schemes for approximate solutions of this problem are established. The generality of the approach considered in this paper, however, allows for treating a wider class of multidimensional problems. Numerical results are provided. © 2018 Author(s)

Stability of the third order partial differential equations with time delay

In the present paper, the initial value problem for the third order partial differential equations with time delay in a Hilbert space with self-adjoint positive definite operator is investigated. The main theorem on stability of this problem is established. The application of this theorem is presented. © 2018 Author(s)

Numerical solutions of the system of partial differential equations for observing epidemic models

In the present paper, stability of initial-boundary value problem for the system of partial differential equations for observing HIV mother to child transmission epidemic models is studied. Applying operator approach, theorems on stability of this problem and of difference schemes for approximate solutions of this problem are established. The generality of the approach considered in this paper, however, allows for treating a wider class of multidimensional problems. Numerical results are provided. © 2018 Author(s)

Crank-Nicholson difference scheme for the system of nonlinear parabolic equations observing epidemic models with general nonlinear incidence rate

In this work, we study second order Crank-Nicholson difference scheme (DS) for the approximate solution of problem (1). The existence and uniqueness of the theorem on a bounded solution of Crank-Nicholson DS uniformly with respect to time step τ is proved. In practice, theoretical results are presented on four systems of nonlinear parabolic equations to explain how it works on one and multidimensional problems. Numerical results are provided. © 2021 the Author(s), licensee AIMS Press

ON STABILITY OF THE THIRD ORDER PARTIAL DELAY DIFFERENTIAL EQUATION WITH NONLOCAL BOUNDARY CONDITIONS

In the present paper, the stability of the initial value problem for the third order partial delay differential equation with nonlocal boundary condition is studied. The first of accuracy absolute stable difference scheme for solution of this problem is presented. Stability estimates for solution of this difference scheme are proved. Numerical results are provided © 2022. Academic Publication