In this work, the mathematical modelling of peristaltic transport for incompressible Sutterby fluid through the cavity between coaxial tubes where the inner tube is fixed and the outer tube has sinusoidal rhythmic fluctuations along the channel’s walls is presented. Under the assumption of long wavelength and the low Reynolds number, the governing equations (motion, temperature, and concentration) are illustrated in cylindrical coordinates. The analytical solution for the temperature and concentration of the fluid flow is obtained using Mathematica 11.3, whereas the perturbation technique is employed to find the closed form of the velocity profile. The variation of the axial velocity, stream function, temperat

Background:. Children with spina bifida occulta require early surgery to prevent neurological deficits. The treatment of patients with a congenitally tethered cord who present in adulthood remains controversial.

Objective: The aim of this study is to describe the outcome obtained in 61 adult patients with congenital TCS and no prior surgical treatment who underwent surgical untethering.

Methods: This prospective study was conducted on 61 adult patients who underwent surgical untethering for spina bifida occulta at four neurosurgical centers in Baghdad / Iraq  between March 2000 and January 2018. Patients who had undergone prior myelomeningocele repair or tet

This article deals with the study of theories about verbal periphrasis as a grammatical construction; the aim of this point it offers good and valid guidelines to improve the linguistic description. The interest in the subject comes from its importance in the process of language teaching for the students of Spanish and to clarify this type of curriculum of this research we analyzed a literary text. From "Zurita"

   In this paper, a mathematical model for the oxidative desulfurization of kerosene had been developed. The mathematical model and simulation process is a very important process due to it provides a better understanding of a real process. The mathematical model in this study was based on experimental results which were taken from literature to calculate the optimal kinetic parameters where simulation and optimization were conducted using gPROMS software. The optimal kinetic parameters were Activation energy 18.63958 kJ/mol, Pre-exponential factor  2201.34 (wt)^-0.76636. min^-1  and the reaction order 1.76636. These optimal kinetic parameters were used to find the optimal reaction conditions which

CdSe quantum dots possess a tuning energy gap which can control gap values according to the size of the quantum dots, this is made the material able to absorb the wavelengths within visible light. A simple model is provided for the absorption coefficient, optical properties, and optical constants for CdSe quantum dots from the size 10nm to 1nm with the range of visible region between (300-730) nm at room temperature. It turns out that there is an absorption threshold for each wavelength, CdSe quantum dots begin to absorb the visible spectrum of 1.4 nm at room temperature for a wavelength of 300 nm. It has been noted that; when the wavelength is increased, the absorption threshold also increases. This applies to the optical propertie