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In this paper, a two-component Lattice Boltzmann Method (LBM) has been utilized to simulate the natural convection of TiO 2 -water nanofluid in a curved geometry. The main purpose of this research is to study the effect of nanoparticle size and also boundary conditions on the thermal characteristics of the nanofluid. Furthermore, the effect of Rayleigh number (Ra) and volume fraction of nanoparticles ( ϕ ) on the average Nusselt number (Nu ave ) have been investigated. Two different thermal boundary conditions, namely adiabatic and constant temperature, have been considered in the current work for the curved boundaries. The Rayleigh number varies from 10 3 to 10 9 . Four different sizes, namely 10, 25, 65 and 90 nm, have been chosen for nanoparticles. Results show that the augmentation of nanoparticle size has a deteriorating effect on the effectiveness of nanoparticles while increasing Ra number and ϕ improves Nusselt number (Nu). It is also shown that the boundary conditions change the enhanced Nusselt number (Nu*). The effect is shown to be due to the variation of nanoparticles motion dictated by the boundary conditions. Furthermore, results reveal that increasing volume fraction increases viscosity which at higher values of ϕ might reduce Nu*. [ABSTRACT FROM AUTHOR]

Applying the domain model to the G(2) gauge group and the thick center vortex model to the SU(2) and SU(3) subgroups of G(2), we calculate the potentials between static sources, as well as some parameters of the vortex profile. Comparing the results obtained from G(2) and its subgroups, we argue that SU(2) and SU(3) gauge groups have important roles in observing confinement in the G(2) gauge group. [ABSTRACT FROM AUTHOR]

Probiotics are live microbial food supplements or their components, which have been shown to have beneficial effects on human health. Probiotics can be bacteria, molds, or yeasts, but most of them fall into the group known as lactic acid bacteria and are normally consumed in the form of yogurt, fermented milk, or other fermented foods. Data from clinical trials have shown contrasting effects and should be interpreted with caution. A large variety of potential beneficial effects have been reported including improvement of intestinal tract health, enhancing the immune system, reducing symptoms of lactose intolerance, decreasing the prevalence of allergy in susceptible individuals, reducing risk of certain cancers, treating colitis, lowering serum cholesterol concentrations, reducing blood pressure in hypertensives, and improving female urogenital infections and Helicobacter pylori infections. The aim of this article is to present a review of the current expanding knowledge of applications of utilizing probiotic microorganisms in the prevention and treatment of several diseases.

This paper has studied a desalination unit with humidification—dehumidification cycle which uses solar energy as its source of heating (SDHD). For thermodynamic analysis, mass and energy balance equations have been written for the humidifier, condenser and other cycle components. The resulted nonlinear equations have been solved simultaneously to study and analyze the effects of cycle parameters on the amount of desalinated water produced by the plant. Therefore the effects of brackish inlet water flow rate, its temperature, solar collector area, condenser characteristic, humidifier characteristic and inlet air conditions on the rate of fresh water production have been investigated and discussed.

The solubilities of carbon dioxide are reported in mixed solvents containing (1.68 to 3.00) kmol/m³ (N-methyldiethanolamine), (0.36 to 1.36) kmol/m³ (piperazine), (0.36 to 1.36) kmol/m³ (tetramethylensulfone or sulfolane), and water for temperatures from (40 to 70) °C and CO2 partial pressures in the range of (30 to 3900) kPa. The results show that piperazine has an effect on the CO2 solubility and sulfolane behaves as a physical solvent.

In this article we discuss some aspects of operational Tau Method on delay differential equations and then we apply this method on the differential delay equation defined byw(u) = 1/ufor 1 =u= 2 and(uw(u))' = w(u-1) foru= 2, which was introduced by Buchstab. As Khajah et al.[l] applied the Recursive Tau Method on this problem, they had to apply that Method under theMathematica softwareto get reasonable accuracy. We present very good results obtained just by applying the Operational Tau Method using a Fortran code. The results show that we can obtain as much accuracy as is allowed by the Fortran compiler and the machine-limitations. The easy applications and reported results concerning the Operational Tau are again confirming the numerical capabilities of this Method to handle problems in different applications.

Two interrelated sequences of polynomials associated with linear partial differential operators with polynomial coefficients are considered. They are the elements of its algebraic kernel and the sequence of canonical polynomials associated with it. These two sequences are used as bases for the numerical approximation of nonhomogeneous partial differential equations by means of two closely related techniques: the Algebraic Kernel Method and a recursive formulation of the Tau Method in two variables discussed in this paper.

The coupled-wave equations describing the optical phase conjugation by degenerate four-wave mixing are usually solved in the so-called slowly varying amplitude approximation, wherein only the first derivatives of the amplitudes of the probe and the conjugate waves are taken into account. Here we solve the coupled-wave equations without this approximation for nonresonance interactions. This leads to an oscillatory dependence of both reflectivity and transmittance on the normalized coupling constant, κL. Also, the intensity distributions of the probe and the conjugate waves show oscillatory beatlike behaviors around the corresponding slowly varying amplitude approximation distributions. These behaviors can be interpreted as the diffraction of the conjugate (probe) wave from a grating resulting from the superposition of the pump–pump and the pump–probe gratings.

Ramsay Hunt syndrome associated with varicella zoster virus reactivation affecting the central nervous system is rare. We describe a 55-year-old diabetic female who presented with gait ataxia, right peripheral facial palsy, and painful vesicular lesions involving her right ear. Later, she developed dysmetria, fluctuating diplopia, and dysarthria. Varicella zoster virus was detected in the cerebrospinal fluid by polymerase chain reaction. She was diagnosed with Ramsay Hunt syndrome associated with spread to the central nervous system. Her facial palsy completely resolved within 48 hours of treatment with intravenous acyclovir 10 mg/kg every 8 hours. However, cerebellar symptoms did not improve until a tapering course of steroid therapy was initiated.

Menstrual cups have been reported to be an acceptable substitute for tampons. These flexible cups have also been reported to provide a sustainable solution to menstrual management, with modest cost savings and no significant health risk.The present article documents the first case of toxic shock syndrome associated with the use of a menstrual cup in a woman 37 years of age, using a menstrual cup for the first time. Toxic shock syndrome and the literature on menstrual cups is reviewed and a possible mechanism for the development of toxic shock syndrome in the patient is described.

The thick center vortex model, with the idea of using domain structures, is used to calculate the potentials between two G(2) heavy sources in the fundamental, the adjoint, and the 27-dimensional representations. The potentials are screened at large distances. This behavior is expected from the thick center vortex model since G(2) has only a trivial center element which makes no contribution to the average Wilson loop at the large distance regime. A linear potential is obtained at intermediate distances for all representations. This behavior can be explained by the thickness of the vortices (domains) and by defining a flux for the trivial center element of G(2). The role of the SU(3) subgroup of G(2) in the linear regime is also discussed. The string tensions are in rough agreement with the Casimir operators of the corresponding representations. [ABSTRACT FROM AUTHOR]