Azad University of Mashhad

Mashhad, Iran

Azad University of Mashhad

Mashhad, Iran
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Niazmand S.,Mashhad University of Medical Sciences | Khooshnood E.,Azad University of Mashhad | Derakhshan M.,Mashhad University of Medical Sciences
Pharmacognosy Magazine | Year: 2010

Background: Achillea is a plant widely used in traditional medicine for gastrointestinal disorders. There are some reports on gastrointestinal effects of Achillea, such as antiulcer, antibacterial, hepatoprotective, choleretic, and antispasmodic. To investigate the effects of aqueous-ethanol extract of Achillea wilhelmsii on rat′s gastric acid output in basal, vagotomized (VX), and vagal-stimulated conditions. Materials and Methods: 24 male Wistar rats were randomly divided into 2 groups: control and test. Gastroduodenostomy was performed for each rat. Gastric content was collected for 30 min by washout technique. One milliliter of 3 doses (0.5, 1, and 2 mg/kg) was introduced into the stomach of each rat in the test group and the same volume of saline was used in the control group. Total titratable acid was measured by a titrator. Results: The extract inhibited acid output significantly in basal condition by 1 and 2 mg/kg doses (P < 0.05) but in VX condition this inhibitory effect on acid output disappeared and the 1 and 2 mg/kg doses increased acid output significantly (P < 0.05 and P < 0.001, respectively). The extract showed a reduction in the acid output in vagal-stimulated condition by 1 and 2 mg/kg doses, which were not statistically significant. Conclusion: These results showed an inhibitory effect of A. wilhelmsii extract on acid output in basal condition. The inhibitory effect of the extract was exerted via gastric vagal parasympathetic nerve.


Niazmand S.,Mashhad University of Medical Sciences | Esparham M.,Azad University of Mashhad | Hassannia T.,Mashhad University of Medical Sciences | Derakhshan M.,Mashhad University of Medical Sciences
Pharmacognosy Magazine | Year: 2011

Background: Teucrium polium L. (TP) have been used in herbal medicine for different purposes such as antispasmodic, antidiabetic and lowering blood lipid. In the present study, the impact of aqueous-ethanol extract of TP on blood pressure, heart rate and intraventricular pressure was investigated in rabbit. Materials and Methods: Twenty-four NWZ rabbits weighed (2-3 kg) were randomly divided into four groups. In each experiment, two groups of six rabbits received jugular injection of either TP extract (20, 40 and 80 mg/kg) or normal saline for blood pressure effects and two groups for intraventricular pressure. Then, blood pressure, heart rate and intraventricular pressure were measured via carotid cannula using pressure transducer connected to a power lab system, and the data were pooled from independent, single-blinded experiments for each group. Results: Treatment with 80 mg/kg of TP extract significantly depressed the mean arterial blood pressure (12.5%, P< 0.05). However, there was no significant decrease in the 20 or 40 mg/kg dose or normal saline treatment group. Moreover, the extract increased (dp/dt)max (P<0.05), maximum left ventricular pressure (LVPmax) (P<0.05) and decreased (dp/dt)min significantly (P<0.05), there was no meaningful effect on left ventricular end-diastolic pressure (LVEDP). Conclusion : The present results demonstrated the extract had no effect on the heart rate, but showed a positive inotropic on the heart and hypotensive effects. These data suggested that hypotensive effect may counterbalance by the inotropic effect of the extract.


Niazmand S.,Mashhad University of Medical Sciences | Esparham M.,Azad University of Mashhad
Pharmacologyonline | Year: 2011

For many years in herbal medicine the antihypertensive and lowering blood lipid properties of Achillea wilhelmsii have been suggested. In the present study the impacts of the plant extract on rabbit's blood pressure, heart rate and intraventricular pressure have been investigated. Twenty four NWZ rabbits weighed (2-3 kg) were randomly divided into four groups. Two groups of 6 rabbits received jugular injection of either A. wilhelmsii extract (20, 40 and 80 mg/kg) or normal saline for blood pressure effects and two groups for intraventricular pressure. Blood pressure, heart rate and intraventricular pressure were measured via carotid cannula using pressure transducer connected to a power lab system. The blood pressure was significantly decreased in 80 mg/kg dose of the extract. However, there were not any significant effects on heart rate in other doses of the extract or normal saline. Although, the extract was significantly decreased (dp/dt) max and left ventricular developed pressure (LVDP), it increased (dp/dt) min. Therefore, it seems that although A. wilhelmsii extract had no effect on heart rate, it showed a negative inotropic effect. Furthermore, the extract reduced blood pressure which may partly due to the negative inotropic effect of the extract.


Yaghouby F.,University of Kentucky | Ayatollahi A.,Iran University of Science and Technology | Bahramali R.,University of Applied Science and Technology of Iran | Yaghouby M.,Azad University of Mashhad
Expert Systems | Year: 2012

In this study, two variants of genetic programming, namely linear genetic programming (LGP) and multi-expression programming (MEP) are utilized to detect atrial fibrillation (AF) episodes. LGP- and MEP-based models are derived to classify samples of AF and Normal episodes based on the analysis of RR interval signals. A weighted least-squares (WLS) regression analysis is performed using the same features and data sets to benchmark the models. Another important contribution of this paper is identification of the effective time domain features of heart rate variability (HRV) signals upon an improved forward floating selection (IFFS) analysis. The models are developed using MIT-BIH arrhythmia database. The diagnostic performances of the LGP and MEP classifiers are evaluated through receiver operating characteristics (ROC) analysis. The results indicate that the LGP and MEP models are able to diagnose the AF arrhythmia with an acceptable high accuracy. The proposed models have significantly better diagnosis performances than the regression and several models found in the literature. © 2011 Blackwell Publishing Ltd.


Mozaheb Z.,Mashhad University of Medical Sciences | Aledavood A.,Mashhad University of Medical Sciences | Farzad F.,Azad University of Mashhad
Pan African Medical Journal | Year: 2012

Background: The role of dietary factors in the epidemiology of Non-Hodgkin's lymphoma (NHL) remains largely undefined. Dietary habits may play a role in the etiology of NHL by influencing the immune system. Methods: Dietary patterns and the risk of NHL were analyzed in a case control study; including 170 NHL cases and 190 controls. All subjects completed a validated food-frequency questionnaire. The dietary pattern was investigated separately and in nine nutritional groups. Crosstab tables were used to estimate the odds ratios (OR), and Ptrend. Results: Consumption of highest versus lowest quartile of proteins (OR, 8.088 Ptrend=0.000), fats (OR, 6.17 Ptrend=0.000) and sweets (OR, 8.806 Ptrend=0.000) were associated with a significantly increased NHL risk. The inverse association was found for fresh fruits (OR, 0.117 Ptrend=0.000) and vegetables (OR, 0.461 Ptrend =0.010). Conclusion: An association between dietary intake and the risk of NHL is biologically plausible due to immunosuppressive effects of fat and animal proteins, and antioxidant properties of vegetables and fruits. © Zahra Mozaheb et al.


Niazmand S.,Mashhad University of Medical Sciences | Khoshnood E.,Azad University of Mashhad
Iranian Journal of Basic Medical Sciences | Year: 2011

Objective(s): Achillea genius is widely used in traditional medicine for gastrointestinal disorders. The aim of this study was to investigate the effects of aqueous-ethanol extract of Achillea wilhelmsii on rat's gastric motility in basal and vagal stimulated conditions. Materials and Methods: Twenty four Wistar rats were randomly divided into two groups: control and test. The extract was prepared by maceration which was used to prepare three 0.5 ml samples of three doses (0.5, 1 and 2 mg/kg) in the test group. The same volume of saline was used in the control group. Gastric motility was measured by inserting a small balloon in the stomach which was connected to a pressure transducer. The data were recorded for 25 min duration after each dose and these data were analyzed for 3 intermittent five min intervals (t1= 0-5, t2=10-15 and t3= 20-25 min). Results: The extract at basal condition decreased intragastric pressure (IGP) by 1 mg/kg dose in the t3 and 2 mg/kg in the t2 and t3 intervals. The extract at vagal stimulated condition decreased IGP by 1 and 2 mg/kg doses in the t2 and t3 intervals. The extract reduced contraction amplitude at basal condition by 2 mg/kg dose in the t2 and t3 intervals. At vagal stimulated condition contraction amplitude was reduced by 1 mg/kg dose in the t2 and t3 by 2 mg/kg in all three intervals. The extract showed no effect on frequency of gastric contraction in either basal or vagal stimulated conditions. Conclusion: The extract showed an inhibitory effect on gastric motility in both basal and vagal stimulated condition. This inhibitory effect may be exerted by an antagonistic effect on acetylcholine dependent calcium influx or release of calcium from intracellular storage in gastric smooth muscle.


Parvaneh V.,Shahrood University of Technology | Parvaneh V.,Azad University of Mashhad | Shariati M.,Shahrood University of Technology
Acta Mechanica | Year: 2011

In this paper, the influence of various vacancy and Stone-Wales defects on the Young's modulus of single-walled carbon nanotubes is investigated via a structural model. Dispersion in experimental results is the motivation for this work. Our results show that the type of method used (loading and boundary condition) for the prediction of the Young's modulus of SWCNTs is very important for the results. The effect of different types of defects on the Young's modulus is also studied for zigzag and armchair nanotubes with various aspect ratios (length/diameter). A comparison of our results with those of experimental methods indicates that for the exact prediction of the Young's modulus of SWCNTs we need to apply the correct conditions. © 2010 Springer-Verlag.


Bidokhti H.S.,Azad University of Mashhad | Enferadi J.,Azad University of Mashhad
International Conference on Robotics and Mechatronics, ICROM 2015 | Year: 2015

In recent years neural networks have been considered as an apposite method for solving problems which come to system of nonlinear equations. On the other hand, in opposite to inverse kinematics problem of parallel manipulators, their direct kinematics problem has very complicated analytical solution which are dependent to solving system of nonlinear equations with numerical methods. Therefore this problem can be a good case for using artificial neural networks. In this paper, direct kinematics problem of a 3-RRR planar parallel robotic manipulator, is solved by using two different models of artificial neural networks, one a back propagation neural network and the other one a radial basis neural network. The proposed networks use training data set which is made by solving the inverse kinematics of the robot. After making the database for training the networks, different parameters of the neural networks are changed in a wide range and finally the best ones for each of BPNN and RBFNN models are selected. Then the number of the data used for training is minimized. So that computation time is optimized. Mean squared error of the proposed BP and RBF neural networks are 7.5×10-6 and 5 × 10-17. Much more precise results in solving FKP of the 3-RRR manipulator and also less computational time of RBFNN is obtained in this study. The designing approach of the proposed solution is presented in detail, and effectiveness of the solution is demonstrated by comparing a simulated spiral path with its real path. Finally the total error during the simulated path is calculated and the average of 4. 5 × 10-4 for BPNN and 1. 59 × 10-6 for RBFNN confirms the reliability of these methods. © 2015 IEEE.


Hasanzadeh F.,Azad University of Mashhad | Naghibzadeh M.,Ferdowsi University of Mashhad
Proceedings of the 2013 3rd IEEE International Advance Computing Conference, IACC 2013 | Year: 2013

The issue in reachability problem of graph G = (V, E) is whether there is a path between two given nodes or not. This problem plays a key role in areas such as Bioinformatics, Semantic Web, Computer Networks and Social Networks, which have very large graph-structured data. Also, the reachability problem is employed considerably in the graph management and graph algorithms. In this paper, we propose a novel labeling approach for large directed graphs. Our presented method is called GRU (Graph Reachability indexing using United intervals), that can answer reachability queries in constant time even for large graphs. The significant point in this approach is that all the reachability information is computed after indexing time. In addition, this computation is performed only with one time DFS (post-order) traverse and labels are calculated precisely and stored in an efficient way. Analytical and experimental results reveal that effectiveness of our method is more than other interval labeling methods. Furthermore, our approach results show improvement in query time in comparison with GRAIL, which is only a scalable index for reachability queries. © 2013 IEEE.


Shaddel M.,Ferdowsi University of Mashhad | Javan D.S.,Ferdowsi University of Mashhad | Baghernia P.,Azad University of Mashhad
Renewable and Sustainable Energy Reviews | Year: 2016

Today, for providing clean energy, solar capturing facilities such as photovoltaic panels (PV) or solar thermal collectors (SCTs) have been increasingly installed worldwide. On the other side, lack of solar radiation data is one of the barriers for developing these technologies locally. Short-time step calculation of solar global irradiation (SGI) on inclined planes is required regarding to predict precise performance of solar systems, leading to enhance security operation's conditions and economic cost saving. Moreover, SGI values on tilted absorbers have a nonlinear relationship with several variables such as Horizontal Solar Global Irradiation, Extraterrestrial Horizontal Global Irradiation, and number of days, collector angle, solar altitude angle and the latitude of the location. Thus computation of SGI is neither readily to obtain nor easy to forecast. This paper is proposed on estimating accurate values of SGI on tilted planes via Artificial Neural Network (ANN). Indeed, ANNs are effective tools to model nonlinear systems and are widely used simulation software incorporated in MATLAB. Mashhad the second megacity of Iran is taken into account for the case study. The ANN is developed and optimized using every 30 min of SGI data (6.00 AM until 5.00 PM) in 2013 on zero, 45° and 60° inclined planes respectively. These data have been gauged by pyranometers which are installed in Air & Solar Institute of Ferdowsi University of Mashhad. Meanwhile, the accuracies including R2 (Correlation Coefficient), MAE (Mean Absolute Error) and RMSE (Root Mean Square Error) are obtained 0.9242, 0.0284, 0.055 and 0.9302, 0.0269, 0.0549 for 60 and 45 tilted collectors respectively. Eventually it is concluded that ANN can be a reliable network and well capable for forecasting solar energy on slope solar absorbers in Mashhad. © 2015 Elsevier Ltd.

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