Background: Contrast of conventional MRI images is influenced by different parameters such as Tl, T2, and proton density that may lead to invisibility and undetectibility of some small lesions in the normal appearing white matter (NAWM) in patients with Multiple sclerosis (MS). Each brain tissue has specific values for Tl and T2 that usually changes in different pathologic lesions, thus, these differences may help clinician to differentiate different pathologies by measurement of these relaxation times. The present study was conducted to determine the association between the Multiple sclerosis and relaxation time of MR in brain tissue. Materials and methods: For this case-control study, 15 patients with MS and 15 normal subjects were selected. MRI was performed in Imam hospital on 1.5Tesla Picker MRI system. First, Tl and T2 maps were computed from two images using spin echo (SE) and inversion recovery (IR) pulse sequences with optimization of interpulse time intervals TE, and TR to minimize errors. Then, Tl and T2 values of brain tissues were measured. Results: Results have revealed that not only Tl and T2 values in MS plaques increase significantly (P<0.0077), but also these values in NAWM increase accordingly Tl of NAWM changes between 2.99% and 10.23% (p Conclusion: Increasing of Tl and T2 in NAWM and decreasing of T2 value in NAGM can be considered as a t\diagnostic parameter of MS diseases.

In this paper, transfinite element method is used to analyze the two dimensional thermoelasticity problems. A comparison is made between the thermoelastic analysis results of the classical theory and theories with one or two relaxation times (i.e. L-S and G-L theories), for the half space problem. Governing equations are transformed to Laplace domain and then, node variables are calculated by the finite element method. Results are transformed to physical domain by the Laplace inverse transform. Finally, results of the three theories are compared and discussed. The obtained results reveal that the tensional stresses predicted by the classical theory for points located before the stress wavefront are higher whereas the compressive stresses predicted by L-S and G-L theories are higher for points located after the stress wavefront. Furthermore, the temperature predicted by the modem theories is higher than that of by the classical theory at the wavefornt.

Dynamic relaxation is an iterative technique, which is used as an equation solver. In this paper, a new time step will be formulated for Dynamic relaxation method. The suggested technique is based on the minimization of residual force in each iteration. Mathematical theories and numerical examples are used to verify efficiency of the formulation. By using optimum time step, mathematical convergence rank of DR algorithm will be infinite and two in linear and nonlinear analyses, respectively. To investigate the capability of the proposed formulation, isotropic plates and frame structure by linear and geometrical nonlinear behaviors are analyzed. This study shows that optimum time step reduces number of convergence iterations.Therefore, the cost and the computational time will be reduced. As a result, the suggested formulation for optimum time step has higher mathematical and numerical efficiency than other common methods, such as constant time step. Therefore, the convergence rate of DR iterations will considerably improve.

The purpose of this work is to investigate the effect of magnetic field direction on heat transfer of Newtonian and non-Newtonian fluids in both uniform and non-uniform forms, with the power-law model by using the Multiple relaxation time lattice Boltzmann method (MRT-LBM) with written computer code by Fortran language. The natural convection is created in the two-dimensional cavity with lozenge barrier and is examined in three different temperature boundary conditions. The cold wall of the cavity is investigated in three modes: smooth, curved and diagonal. The results show that increasing the Rayleigh number and decreasing the power-law index and the Hatmann number increase the strength of fluid flow and heat transfer. The smooth design of the wall increases the average Nusselt number by about 30%. Placing the barrier at a constant cold temperature increases the average Nusselt number by 20% on average. The effect of the magnetic field is highest for the smooth wall and lowest for the diagonal wall and this effect decreases with increasing the power-law index. In general, an applied non-uniform magnetic field increases the average Nusselt number by about 10% and increases the flow strength. The effect of wall shape and type of magnetic field applied on shear thickening fluid is negligible. Further reduction of flow strength and average Nusselt number is observed by applying a magnetic field horizontally.

Background and Objective: Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease, leading to progressive disability, reduces daily activity and function and emerges with a wide range of physical symptoms. This study was done to determine the effect of relaxation on the physical symptoms in women with Multiple Sclerosis.Methods: In this clinical trial study, 50 patients with MS were randomly divided into relaxation and control groups. In the interventional group, Jacobson and Benson method was performed for 4 weeks, twice a week for 40 minutes and patients in the control group were received only care and routine medical treatment. Data was collected via fatigue severity scale (FSS), numerical rating scale (NRS) before, immediately after and two months after intervention.Results: The mean severity of fatigue score, before, immediately and two months after the intervention were not the same and time trends was effective on severity of fatigue score (P<0.05). The mean of fatigue score were significantly reduced in intervention group (immediately and two months after intervention) in compared to pre-intervention. The mean severity of pain score, before, immediately and two months after the intervention were not the same and time trends was effective on mean severity of pain score (P<0.05). The mean intensity of pain score over time in the relaxation group non-significantly reduced in compared to the control group.Conclusion: relaxation technique is effective as a low-cost, safe and easy method to reduce fatigue and pain in patients with MS.

In this paper a new time step will be formulated for Dynamic relaxation method. For this purpose, residual force is minimized in each iteration. Calculation of the convergence rate shows the advantage of the recommended technique. For illustrating usability of this method, some plane and space trusses have been analyzed. In this paper, geometrical non-linearity is considered. Moreover, proposed method is widely examined by author's computer program and some examples will be given.

Background and aims: Multiple sclerosis (MS) patients compared to healthy subjects have much higher levels of psychological disorders such as depression, anxiety and stress that greatly affect their quality of life and significant role in stimulating the onset of MS, worsening symptoms and increasing fatigue. relaxation in complementary medicine is the most common treatments with low cost. This study aimed to determine the effects of relaxation on depression, anxiety, stress and in women suffering of MS.Methods: This study is a randomized clinical trial that was carried out on 50 patients with MS referred to MS Clinic of Kashani Hospital in Isfahan, Iran. After simple non-random sampling, participants were randomly assigned by minimization method to three groups: Reflexology, relaxation, and control groups. In the experimental group was performed relaxation intervention within 4 weeks, twice a week for 40 min and the control group were received care and routine medical treatment as directed by a doctor? Data were collected through DASS-21 questionnaire before, immediately and 2 months after interventions in two groups. Data analysis was performed by SPSS using descriptive and inferential statistics.Results: Mean scores of stress, anxiety, and depression before the intervention showed no significant difference in the two groups (P>0.5), but immediately after the intervention, independent t-test showed significant difference between mean scores of stress (P=0.001), anxiety (P=0.02) and depression (P=0.02) between groups while two months after the intervention there was only a significant difference between the mean score of stress in the two groups (P=0.003). Also, findings obtained from repeated measures analysis of variance showed that the severity stress, anxiety and depression during the different times in experimental group had significant difference (P<0.001); while, this difference was not significant in the control group (P>0.05).Conclusion: It seems that relaxation technique as intervention in reducing stress, anxiety and depression is effective in women with MS. However, the technique has long-term effects on stress. So, this method as effective technique can be recommended.