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Pistachio is the second largest non-oil export in Iran. The most important problem in pistachio export is its contamination with aflatoxin. Therefore, this study aimed to evaluate the effects of several physical and chemical methods on the qualitative, qualitative and sensory properties of pistachios from Iran as well as the associated residual aflatoxin levels. This study investigated the effects of roasting (temperature 120 °C for 20 and 40 min), gamma radiation (2.5 and 5 KGy), and microwave (1 and 2 min) methods on pistachios and their qualitative characteristics, including moisture, colour, and sensory properties. In addition, aflatoxin B1 and total aflatoxins were artificially added to pistachios to determine the level of aflatoxin remaining after chemical and physical methods. The results showed that the lowest residual level of aflatoxin B1 was related to combined microwave and irradiation methods. Further, the combined methods showed the lowest total aflatoxins residue so the lowest total aflatoxins residue after chemical contamination of 8 μg/kg aflatoxin was related to the combined methods of 5 KGy irradiations with 2 min of the microwave. In addition, the microwaved and irradiated samples did not differ significantly from the control samples in terms of sensory characteristics (P more...

In this paper, the symmetry reduction method and Nucci’s reduction method are used to obtain exact solutions to the Triki–Biswas equation. Furthermore, the new conservation theorem is utilized for finding the conservation laws of the given model. The conservation laws are derived for each admitted symmetry of the Triki–Biswas equation and satisfy the divergence condition. The 3D, contour and 2D figures are finally plotted to show the dynamics of the obtained exact solutions. more...

A new generalized KdV equation, describing the motions of long waves in shallow water under the gravity field, is considered in this paper. By adopting a series of well-organized methods, the Bäcklund transformation, the bilinear form and diverse wave structures of the governing model are formally extracted. The exact solutions listed in this paper are categorized as lump-type, complexiton, and soliton solutions. To exhibit the physical mechanism of the obtained solutions, several graphical illustrations are given for particular choices of the involved parameters. As a direct consequence, diverse wave structures given in this paper enrich the studies on the KdV-type equations. more...

In an accelerated expanding universe, one can expect the existence of an event horizon. It may be interesting to study the thermodynamics of the Friedmann-Robertson-Walker (FRW) universe at the event horizon. Considering the usual Hawking temperature, the first law of thermodynamics does not hold on the event horizon. To satisfy the first law of thermodynamics, it is necessary to redefine Hawking temperature. In this paper, using the redefinition of Hawking temperature and applying the first law of thermodynamics on the event horizon, the Friedmann equations are obtained in f(R) gravity from the viewpoint of Palatini formalism. In addition, the generalized second law (GSL) of thermodynamics, as a measure of the validity of the theory, is investigated. more...

Thermodynamics of the evolving Lorentzian wormhole at the apparent horizon is investigated in [Formula: see text] gravity. Redefining the energy density and the pressure, the continuity equation is satisfied and the field equations in [Formula: see text] gravity reduce to the ones in general relativity. However, the energy–momentum tensor includes all the corrections from [Formula: see text] gravity. Therefore, one can apply the standard entropy-area relation within [Formula: see text] gravity. It is shown that there may be an equivalency between the field equations and the first law of thermodynamics. It seems that an equilibrium thermodynamics may be held on the apparent horizon. The validity of the generalized second law of thermodynamics (GSL) is also investigated in the wormholes. more...

The aim of this paper is to present solitary wave solution of two different forms of regularized long-wave equation with time-dependent coefficients that models shallow-water waves in fluid dynamics and some phenomena in elastic media, optic fibres and plasma physics. The simplest equation method is applied to solve the governing equations and then exact 1-soliton solutions are obtained. It is shown that this method provides us with a powerful mathematical tool for solving nonlinear evolution equations with time-dependent coefficients in mathematical physics. more...

In this paper, the modified simple equation method is used to construct exac t periodic and soliton solutions of some nonlinear partial differential equations. Exact solutions of the nonlinear Schr ¨ odinger equation, the Hamiltonian amplitude equation, Klein-Gordon equation in 1+2 dimension, the coupled Klein-Gordon equation, the (2 + 1)-dimensional long-wave-short-wave resonance interaction equation, the modified KdV-KP equation and the modified Benjamin-Bona-M ahony equation are successfully obtained. These solutions may be important of significance for the explanation of some practical ph ysical problems. more...

Nonlinear Schrödinger type equations arise from a wide variety of fields, such as fluids, nonlinear optics, the theory of deep water waves, plasma physics, and so on. In this paper, two integration schemes are employed to obtain solitons, periodic waves and other forms of solutions of the coupled nonlinear Schrödinger type equations. The two schemes that are studied in this paper are the Bäcklund transformation of Riccati equation and the trial solution method. more...

The effect of shot-peening on the uniaxial fatigue behaviour of four engineering steels, heat treated to a similar final hardness was investigated. Forged 0.39%C and 0.72%C steels, a quenched and tempered 0.51%C steel and a 0.50%C powder forged (PF) steel were fatigue tested under fully reversed (R=-1) push-pull loading conditions. Following long life (107) cycling, shot-peening had little effect on the fatigue limit of the 0.39%C and 0.72%C steels whereas the fatigue limit of the PF steel increased 10.4%. Conversely, the fatigue limit of the quenched and tempered steel decreased 12.0% after shot-peening. The results showed that the beneficial effects of shot-peening, such as compressive residual stresses and work hardening, balanced the effects of surface roughness since crack initiation tended to occur below the surface. Microhardness profiles showed that the greatest amount of cyclic softening in the shot-peened regions occurred in the hot rolled steels. Softening was accompanied by a decrease in the depth of surface hardness. more...

The uniaxial fully reversed (R = –1) long life fatigue behavior of four shot-peened engineering steels with approximately the same hardness was investigated. Shot-peening, air-cooled forged AISI 1141 and crackable AISI 1070 steels had little effect on their fatigue limits (+2.5 and –2.0 pct, respectively). In the case of a powder forged 0.5 pct C steel, an increase in the fatigue limit of 10.4 pct was observed, albeit with a large standard deviation. Shot-peening quench and tempered AISI 1151 steel decreased its fatigue limit 12.0 pct, as a result of cyclic softening. In general, the beneficial effects of shot-peening these smooth specimens were relatively small. Neither cyclic softening nor hardening occurred in the non–shot-peened steels cycled under the same conditions. more...

In this study prediction of the steady-state flow of branched polymer melts in pipe geometry with finite volume method is presented. The fluid is modelled using a modification of the Pom-Pom model known as the single eXtended Pom-Pom (XPP) where viscoelastic fluid, is typically a commercial low-density polyethylene. In finite volume method, the operator-integration is used to discretize the governing equations in space or control volume. An iterative solution algorithm that decouples the computation of momentum from that of stress is used to solve the discrete equations. Numerical results are presented; include the profiles of all relevant stresses, the axial velocity, stretch and the viscosity across the gap, demonstrating the performance of the model predictions. The influence of the model parameters on the solution and flow behaviour is described and, in particular, the dependence of velocity and stresses distribution as a function of Weissenberg number is analyzed. Finally, for rectitude and accuracy, the verification of this model is performed with the Gieskus model that shows good conformity between the results. more...

A theoretical solution is presented for the convective heat transfer of Giesekus viscoelastic fluid in pipes and channels, under fully developed thermal and hydrodynamic flow conditions, for an imposed constant heat flux at the wall. The fluid properties are taken as constant and axial conduction is negligible. The effect of Weissenberg number (We), mobility parameter (α) and Brinkman number (Br) on the temperature profile and Nusselt number are investigated. The results emphasize the significant effect of viscous dissipation and fluid elasticity on the Nusselt number in all circumstances. For wall cooling and the Brinkman number exceeds a critical value (Br 1), the heat generated by viscous dissipation overcomes the heat removed at the wall and fluid heats up longitudinally. Fluid elasticity shifts this critical Brinkman number to higher values. more...

An analytical solution is presented for the forced convection and entropy generation of a viscoelastic fluid obeying the Phan-Thien–Tanner (PTT) constitutive equation in a concentric annulus with relative rotation of the inner and outer cylinders. Two different types of boundary conditions are considered: at the first case both cylinders are isothermal and kept at different temperatures and in the second case the heat flux is kept constant at the outer cylinder and the inner one is isothermal. Analytical expressions for dimensionless temperature profile (Θ), dimensionless entropy generation number (NS), and the Bejan number (Be) are obtained. The effect of velocity ratio (β), the group parameter (Br/Ω), the Brinkman number (Br), and fluid elasticity (eWe2) on the above parameters are investigated. The results show that the total entropy generation number decreases as the fluid elasticity increases. The results also show that entropy generation number increases with increasing Brinkman number. more...

An approximate analytical solution is derived for the steady state, purely tangential flow of a viscoelastic fluid obeying the Giesekus constitutive equation in a concentric annulus with inner cylinder rotation. An approximation is used for the estimation of radial normal stress. The effect of Weissenberg number ( We ), radius ratio ( κ ) and mobility factor ( α ) on velocity distribution and fRe are investigated. The results show that the velocity gradient near the inner cylinder increases as the fluid elasticity increases. The results also show that fRe decreases with increasing fluid elasticity. more...

An approximate analytical solution is derived for the Couette–Poiseuille flow of a nonlinear viscoelastic fluid obeying the Giesekus constitutive equation between parallel plates for the case where the upper plate moves at constant velocity, and the lower one is at rest. Validity of this approximation is examined by comparison to the exact solution during a parametric study. The influence of Deborah number (De) and Giesekus model parameter (α) on the velocity profile, normal stress, and friction factor are investigated. Results show strong effects of viscoelastic parameters on velocity profile and normal stress. In addition, five velocity profile types were obtained for different values of α, De, and the dimensionless pressure gradient (G). more...

The objective structured examination is one of the most valid, reliable, and effective tools for assessing clinical and communication skills, often by use of standard patients (SPs). SPs can also be assessors of those skills. One of the crucial areas when utilizing SP-based assessment is the quality and consistency assurance of their portrayal of the case and their ability to fill in checklists in an adequate way. The aim of this study was to assess the validity and reliability of SPs’ ability to assess students’ communication skill via a Calgary-Cambridge checklist. This cross-sectional and correlational study was conducted at the Tehran University of Medical Science. We first analyzed validity; the criterion validity of the SPs’ filling in the checklists was assessed through determining the correlation between the SPs’ completed checklists and the checklists filled in by three physician raters individually and then reproducibility: it was assessed by a test-retest approach inter-rater reliability. The mean correlation for assessing the validity of SPs’ completed checklists by individual SPs was 0.81. The inter-rater reliability was calculated by kappa coefficient, and the total correlation among the three raters was 0.85. The reliability of the test-retest approach showed no significant differences between the test and re-test results. The increased number of medical students and different faculties’ responsibilities such as doing educational, research, and health services duties assessing medical student communication skills is a complex issue. The results of our study showed that trained SPs can be used as a valid tool to assess medical students’ communication skills, which is also more cost effective and reduces work load of medical faculties. more...

We aimed to determine the rate of hospital discharge, average length of stay and bed occupancy rate in different hospital wards around the country. The survey consisted of health care service activities from 452 university-related hospitals in the country with a total of 59,348 beds. Because of missing data, the use of 56,315 of these beds was analysed. The countrywide discharge rate was 68.32 patients/1000 population per year with an average length of stay of 3.60 days and a bed occupancy rate of 57.44%. The data could be used to design a framework for prediction of inpatient health care facilities needed in the future. more...

We aimed to determine the rate of hospital discharge, average length of stay and bed occupancy rate in different hospital wards around the country. The survey consisted of health care service activities from 452 university-related hospitals in the country with a total of 59 348 beds. Because of missing data, the use of 56 315 of these beds was analysed. The countrywide discharge rate was 68.32 patients/1000 population per year with an average length of stay of 3.60 days and a bed occupancy rate of 57.44%. The data could be used to design a framework for prediction of inpatient health care facilities needed in the future more...