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Showing 16 results for Kalhor


Volume 9, Issue 3 (Summer 2021)
Abstract

Aims: Dermatoglyphic is the study of skin patterns on hands and feet. It has been shown in some studies that specific finger patterns could be a risk factor for breast cancer. Thus, this study aims to evaluate fingerprint patterns and other easy-to-obtain features in the risk of breast cancer.
Instrument & Methods: This descriptive study was conducted in 2020. A dataset containing 462 records included female patients in Imam Khomeini Hospital Complex, Tehran, Iran. The factors' weight was determined by the Information Gain index. Predictive models were built once without fingerprint features and once with fingerprint features using Naïve Bayes, Decision Tree, Random Forest, Support Vector Machine, and Deep Learning classifiers. RapidMiner 9.7.1 Software was used.
Findings: The most important factor determining breast cancer were age, having a child, menopause situation, and menopause age. The best performance was the Random Forest model with accuracy and Area under Curve of a Receiver operating characteristic of 84.43% and 0.923, respectively. The fingerprint patterns feature increased the RF accuracy from 79.44% to 84.43%.
Conclusion: An early breast cancer screening model could be built with the use of data mining methods. The fingerprint patterns could increase the performance of these models. The Random Forest model could be used. The results of such models could be used in designing apps for self-screening breast cancer.

Mahmoud Reza Rafiee, Hamid Reza Kalhor, Mohammad Marandi, Seyed Javad Mowla,
Volume 10, Issue 0 (پاییز و زمستان86- 2008)
Abstract

Clinical application of embryonic stem (ES) cells faces difficulties regarding tissue rejection as well as ethical limitations. One solution for these issues is to reprogram somatic cells by the injection of their nucleus into an enucleated oocyte or zygote. However, technical complications and ethical considerations have impeded the therapeutic implications of this technology. An approach which is most recently developed is in vitro induction of reprogramming in adult cells. This was first achieved by using four transcription factors, including Oct4, Sox2, c-Myc and Klf4. Subsequently, many ongoing efforts were performed for enhancing this method, also for making it compatible with clinical applications. However, there is still a long road ahead. In this paper we review strategies to reprogram somatic cells to embryonic state and discuss about the recent strategy and the relevant developments.

Volume 10, Issue 4 (Fall 2019)
Abstract

Introduction: Since the gastrointestinal system plays an important role in the function of the immune system, its role in the control or treatment of autoimmune diseases cannot be ignored. Therefore, the intestinal strengthening, which much of gastrointestinal function depends on it, can be effective in this direction. Also, because the intestine plays an important role in the immune system in addition to digestion, it can help maintain the immune system's function by keeping its bacteria balanced. In this regard, probiotics and prebiotics can be useful, which this issue was investigated in the present study.
Conclusion: Probiotics have an important role in the prevention and control of multiple sclerosis.
 

Volume 10, Issue 4 (Fall 2022)
Abstract

Aims: One of the professional duties of nurses is providing the education needed to continue patients' medical treatment at home, influenced by their knowledge, skills, and attitudes. This study aimed to determine the knowledge, skills, and attitudes of nurses and nursing students toward family drug education in pediatric wards.
Instruments & Methods: This descriptive-analytical study was conducted on 300 nurses and nursing students in the pediatric wards of hospitals affiliated with Isfahan University of Medical Sciences. Knowledge, skills, and attitudes of nurses and students concerning patient and family education in pediatric wards were assessed using a researcher-made questionnaire. Data were analyzed using SPSS 16 software.
Findings: All nurses and students agreed with teaching families the safety tips of home medication, but only 60% of nurses and 65% of students agreed with teaching families about drug side effects. Also, there was a significant relationship between the viewpoints of nurses and students regarding the non-use of drugs in the case of teaching drug side effects to the family and their pharmacological knowledge and performance (p<0.05). Students’ knowledge and performance of home pharmaceutical care indicated statistically significant differences with nurses (p<0.05).
Conclusion: Knowledge of pharmaceutical care at home among nurses and students who do not have a positive attitude towards educating families in some areas is not satisfactory.
Elahe Mahmoudi, Hamid Reza Kalhor, Mohammad Hossein Yadegari, Majid Sadeghizadeh, Zohair Hassan,
Volume 12, Issue 4 (10-2010)
Abstract

Objective: The secreted aspartic proteinases (Sap2) of Candida albicans has prominent role on Candida adherence, invasion, and pathogenicity. The aim of this study was cloning, expression and characterizing of Sap2 enzyme. Also in this study for the first time, the expression system P. pasturis was used for expressing the recombinant protein. Materials and Methods: C. albicans Sap2 gene was amplified by PCR with sticky ends, EcoR1 and SacII, and it was subcloned into the T/A vector. The sequencing of this gene was done with universal primers and then the Sap2 gene was cloned into pGAPZαA expression vector. The construct was transformed into P. pasturis yeast; the Sap2 gene integration into the yeast genome was accomplished by the homologous recombination. The expressed protein was confirmed by western blotting using monoclonal antibody against Sap2 protein. Finally, the recombinant protein was purified by Ni-NTA chromatography column, and the activity of the enzyme was confirmed. Results: In this study, we successfully amplified C.albicans Sap2 gene and subsequently integrated into the yeast pichia pasturis genome by homologous recombination. Moreover, we were able to identify a yeast clone secreting the recombinant protein. The optimum over expression of sap2 protein was obtained after 96 h, at 30ْ C. Conclusion: Expression of Sap2 gene in P. pasturis, in comparison to bacterial expression system, leads to a high-level expression, and also need for post translation modifications, that might be required for the activity of enzyme, is obviated in the yeast system. Based on our results, the purified acid aspartyl proteinase purified from P. pasturis was capable of degrading BSA as a substrate in-vitro. The recombinant Sap2 protein had maximum activity in an acidic pH.

Volume 15, Issue 12 (2-2016)
Abstract

This paper presents implementation of position control for planar cable-driven parallel robots using Visual servoing. The main contribution of this paper contains three objectives. First, a method is used toward kinematic modeling of the robot using four-bar linkage kinematic concept, which could be used in online control approaches for real-time purposes due to decreasing of the unknown parameters and computation time. In order to track the position of End-Effector, an online image processing procedure is developed and implemented. Finally, as the third contribution, two different controllers in classic and modern approaches are applied in order to validate the model with plant and obtain the most promising controller. As classic controller, pole placement approach is suggested and results demonstrate weaknesses in modeling the uncertainties although they represent acceptable performance. Due to the latter incapability, sliding mode controller is utilized and experimental tests represent effectiveness of this method. Result of the latter procedure is an inimitable operation on the desired task however, it suffers from chattering effect. Moreover, results of these controllers confirm accommodation between the model and robot. The whole procedure imposed, could be applied for any kind of cable-driven parallel robot.

Volume 16, Issue 1 (3-2016)
Abstract

Ionic polymer metal composite (IPMC) actuator is a group of electro-active polymer (EAP) which bends in response to a relatively low electrical voltage because of the motion of cations in the polymer network. IPMC has a wide range of applications in robotics, biomedical devices and artificial muscles. The modeling of the IPMC actuator is a multi-physics task as it involves the electricity, chemistry, dynamics and control fields. Due to its complexity and nonlinearity, IPMC modeling is difficult in terms of mathematics and its behavior is still not fully agreed upon by researchers. This paper presents a novel discrete-time model with state-dependent parameters (SDP) for identification of the nonlinear response of an IPMC actuator. A single-input single-output nonlinear identification algorithm is formulated and demonstrated for an IPMC actuator that exhibit both soft and hard nonlinearities. The nonlinear characteristics of the identified system are represented with coefficients which are a function of the input and output states. Following the SDP algorithm, the model is identified from input–output data to represent the model parameters as functions of past inputs and outputs. The proposed modeling approach is validated using an existing model and show exact representation of the non-linear behavior of the IPMC actuator

Volume 16, Issue 7 (9-2016)
Abstract

In this paper, a trajectory tracking control strategy for a quadrotor flying robot is developed. At first, dynamic model is obtained by lagrange-euler approach. Then, control structure, consisting of a model-based predictive controller, has been used based on state space error to track transitional movements for reference trajectory and also robust nonlinear H∞ control is applied for stabilizing the rotational movements and reject the external disturbance. In both controllers the integral of the position error is considered, allowing the achievement of a null steady-state error when sustained disturbances are acting on the system. The external disturbances is considered as aerodynamic torques. If uncertainties increase, the designed control system will be unable to track and stabilizing perform properly and completely. So finally, in order to eliminate the effects of parameter uncertainties the recursive least squares is used for estimating mass and moment inertia parameters which are linear and it is applied to the control system. Simulation results show that by using estimation of system parameters, the proposed control system has a promising performance in terms of stabilization and position tracking even in the presence of external disturbance and parametric uncertainties.

Volume 16, Issue 11 (1-2017)
Abstract

In this paper, using both linear and nonlinear identification methods based on iterative and recursive least-square, the performance of a backstepping control system of a quadrotor in the presence of uncertainties is improved. At first, the dynamic model of a quadrotor is introduced and descriptive equations are presented in an appropriate state-space in order to design a controller based on backstepping method. Then the backstepping controller is designed using virtual controller for trajectory tracking. In this control system, the control performance is not satisfying because of the physical uncertainties existed in quadrotor. Consequently, an online identification method is introduced and used to improve the performance of the controller. In this regard, some parameters, which are linear in the model structure, are identified by least square error technique and iterative least square method is used for identifying other parameters.The results indicate that the steady-state error is decreased and the ability of tracking of a desired trajectory in the presence of uncertainties is increased. Furthermore, the result demonstrate the stabilization of roll and pitch angles, while, the method prevents the vibration of control forces.

Volume 17, Issue 10 (1-2018)
Abstract

In this paper, position control is addressed for a pneumatically actuated 6-DoF Gough-Stewart parallel robot. At first, dynamic model of the pneumatic system of each link of the robot which comprises a pneumatic actuator and a proportional electrical control valve is extracted. Unknown parameters of the obtained dynamic model consisting friction force, viscous coefficient and the parameters of the valve are identified by employing an evolutionary algorithm. Then, position control of the robot’s pneumatic actuator is performed based on designing Backstepping-Sliding Mode controller according to the nonlinear dynamic model of the pneumatic system. Moreover, kinematic equations of the 6-DoF parallel robot are achieved and a novel method is proposed, the so-called Geometry-based Quasi-Forward Kinematic, to the end of calculating the position of the end-effector of the robot without using expensive position sensors. Accordingly, kinematic closed-loop control of the parallel robot, which is based on simultaneous joint space and task space control, is investigated for trajectory tracking using potentiometers, a rotation sensor, and based on the computed position of the end-effector by the proposed method. Desired sinusoidal trajectories with pure motions and also complicated trajectories are tracked in which error of positions and rotations are lower than 2 (cm) and 3 (deg), respectively. The results reveal that the trajectory tracking control of the pneumatic 6-DoF Gough-Stewart parallel robot is performed properly based on the proposed control strategies and the novel method for calculating the position of the end-effector.

Volume 17, Issue 11 (1-2018)
Abstract

In hovering, the deputy satellite must use fuel regularly to maintain a constant distance from a source point. Since the amount of fuel in satellites is a key element, it has also a great value to optimize its consumption. The system speed and the time of reaching stability are also other important elements that have been studied in this study. For this purpose, three useful controllers are used. These controllers are LQR controller, Pole Placement and sliding mode controller. In the following, these controllers were optimized using particle swarm optimization algorithm in order to compromise the amount of fuel consumption and the time of reaching stability. Comparing the final results shows that the sliding mode controller can be the best option for optimizing hovering system.

Volume 17, Issue 11 (1-2018)
Abstract

This paper aims at proposing an algorithm for collision-free motion planning of two wheeled mobile robots. The proposed approach relies on discrete motion planning, convex optimization and receding horizon control (RHC) concepts. The proposed algorithm is employed for motion planning and control of a mobile robot in order to pass through an unknown environment both in simulation and practical implementation. In this regard, CVX package benefited from the Gurobi solver is employed to solve the optimization problem in the simulation. Moreover, in order to perform a collision-free motion planning, corresponding Robot Operating System (ROS) package with the intended mobile robot is employed to cooperate with the provided motion planner package. The provided package utilizes educational license of Gurobi optimizer solely to speed up solving proposed optimization problem and its built in branch and bound for Mixed Linear Integer Programming (MLIP). In order to keep the linear form of the constraints, a combination of the Velocity Obstacle (VO) in the first horizon and Bug method concept for the rest of the horizons is used. Obtained results show the reliability of this algorithm for safe collision avoidance. The reported results reveal this fact that by considering the maximum velocity of the E-puck, obtained computational time is less than 0.004 sec. in each stage which is fast enough for robot motion planning tasks.

Volume 18, Issue 3 (5-2016)
Abstract

Five demersal trawl surveys were conducted in the Pakistani waters in October, November 2009 and August, October, November 2010. A total of 819 length-weight and 7,240 length-frequency data of Atrobucca alcocki were collected, the length ranged from 10 cm to 45 cm with the dominant length group from 19 to 29 cm. The total weight ranged from 14 to 928 g. The length-weight relationship can be expressed as W= 0.012*L2.925 (R2= 0.972). Using the ELEFAN program in FiSAT computer package, the calculated von Bertalanffy growth function parameters were = 47.25cm, K= 0.180 yr-1. Total mortality (Z) was computed using the length-converted catch curve analysis at Z= 1.07 yr-1. Natural mortality was computed as M= 0.494 yr-1 at an annual average sea surface temperature of 26°C, hence, the fishing mortality was computed as F=Z-M= 0.576 yr-1. The Exploitation ratios (E) were computed as Emax = 0.421, E10 =0.355, E50 =0.278. Yield per recruit analysis revealed that when tc was assumed to be 2, Fmax was calculated at 0.75 and F0.1 at 0.6. When tc was assumed to be 1, Fmax was calculated at 0.55 and F1.0 at 0.45. Current age at first capture was about 1 year and Fcurrent was 0.576, therefore, Fcurrent was larger than F0.1 and Fmax. When biological reference point was Fopt equal to M (0.494), current fishing mortality rate of 0.576 was larger than the target biological reference point.

Volume 19, Issue 1 (January 2019)
Abstract

This article investigated design and construction of a 4-DOF delta parallel robot’s components and additionally inverse kinematics and kinematics control of the robot. The initial and final version of the robot based on existing needs, the addition of gearboxes due to the low torque of motors, and flange transformations to connect the gearbox to the robot's base were also discussed. In the following, by simulating the robot in MATLAB software, the integrity of the inverse kinematic equation of the robot was investigated. In the other part, the design of the kinematic control in the joint space was discussed and the results were plotted in the graphs for a z-direction. By designing a suitable robot controller, tracing the desired path and comparing its results with other controllers become possible. By designing a conveyor for the robot and equipping it with a camera, detecting the objects that the robot moves them become possible with image processing. For the purpose of picking and placing the objects, the robot's end effector is equipped with a controlled suction.  The results, through which the paths crossed, showed the designed PID controller for the robot was working correctly and the desired path was followed with small error.

M.r Kalhori, Sh. Irani, M. Soleimani, E. Arefian, F. Kouhkan,
Volume 22, Issue 1 (Winter 2018)
Abstract

Aims: Glioblastoma multiforme is a type of brain cancers that do not respond well to treatment. The poor prognosis of this disease is due to the presence of radiation resistance and chemotherapy. The purpose of the present study was to produce miR-579 precursor carriers and investigate the effect of increased expression of miR-579 on the expression of BAX and CDKN1A genes in the glioblastoma cell line.
Materials and Methods: In this experimental study, in order to produce recombinant lentiviral vectors, a gene containing the miR-579 precursor sequence was cloned into the plasmid. The recombinant structure was transmitted to the cells of HEK293T with and pMD2 plasmids. Viral particles were concentrated using Ultra Centrifuge. Viral titration was calculated by flow cytometry. The viral particles produced were transferred to the A-172 cell line. Finally, by using Real-Time PCR, changes in expression levels of miR-579 and BAX and CDKN1A genes were investigated.
Findings: The presence of miR-579 gene precursor in the plasmid was confirmed by colony PCR and sequencing methods. The study showed that the level of miR-579 expression in infected cells with the recombinant virus was found to be up-regulated compared to the control group. miR-579 increased the BAX gene expression by three times. But, there was no significant change in the expression of CDKN1A gene expression.
Conclusion: Increased expression of miR-579 in the A-172 cell line could increase the expression of BAX gene. However, the CDKN1A gene expression does not change significantly.
 


Volume 23, Issue 1 (Spring 2023 2023)
Abstract

Aim and Introduction 
The poverty is not affected only by income level. Some variables such as lack of access to welfare and health facilities, deprivation of education, physical weakness and vulnerability to diseases can be influential factors in poverty. Accordingly, indexes such as the poverty line, the percentage of poor people, and the intensity of poverty, which are used to study of the poverty in the society, do not fully represent the situation of poverty dimensions. Therefore, for measuring poverty in different dimensions, Oxford Poverty and Human Development Initiative in collaboration with United Nations Development Programme introduced the Multidimensional Poverty Index in 2010. This index includes deprivations such as low levels of health, lack of education, inadequate living standards, disability, low quality work, threats of violence, and living in areas with hazardous environments that poor people face in their daily lives. Several researches have been conducted on multidimensional poverty at the national and international levels, which have estimated the multidimensional poverty index using the Alkire-Foster methodological framework. At the same time, the multidimensional poverty of children has been neglected at the national level. This paper aims to study of multidimensional poverty among Iranian children based on the Alkire-Foster methodological framework. The multidimensional poverty of under five children using Multiple Indicator Demographic and Health Survey data in four dimensions of "living standards", "health", "support" and "development" has been measured.
Methodology
The Alkire-Foster methodology has been used for measuring the multidimensional poverty index. For measuring the children multidimensional poverty index (MPI) in Iran, data of the Multiple Indicator Demographic and Health Survey has been used. This survey covers the latest available data on various sociodemographic and health subjects of children, women and men. A comprehensive and new framework for measuring child poverty in Iran has been provided using the indicators of child mortality, cooking fuel, drinking water, sanitation discharge and housing from the global framework. The other indicators such as vaccination index and insufficient care has been extracted from other researches.
Findings
The results show that MPI of children in Iran is equal to 0.002. The incidence of multidimensional poverty is 0.5% and the intensity of child poverty is 38.6%. In general, the results show that girls compared to boys experience more multidimensional poverty and as mothers' education levels increase, children experience less multidimensional poverty. Children who live in large households (5 people or more) experience more multidimensional poverty compared to children who live in small households. Children in developed provinces experience multidimensional poverty less than other children and finally, children under five in the first economic quintile (the lowest economic level of the society) have the highest multidimensional poverty among all households in Iran.
Among children under five whose mothers have primary education, "health" dimension plays the most important role in measuring the multidimensional poverty index. In less developed provinces, the most important factor in mesearunig multidimensional poverty among children under five is "child development" dimension. Also, in households that have a low level of economic and social status (based on economic quintile variable), “child development " and "living standards” are important respectively.
Discussion and Conclusion
The purpose of presenting the Child multidimensional poverty index is to provide understandable and important statistics for clarify level and form of multidimensional poverty. The findings of this study, which was conducted for the first time in Iran, show that although value of the child multidimensional poverty index based on "living standards”, "health", "support" and "child development" is not a large number, however children in social and demographic groups have had encounters with different levels of multidimensional poverty. Considering that the growth and development of the children in the appropriate context is the basis for formation of a healthy and stable family and developed society, it is necessary to make policies in order to reduce the multidimensional poverty of children.

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