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Prevalence of flat foot and hallux valgus deformity among primary school female students in Kiar city of Chaharmahal and Bakhtiari
Sedighe Sadat Mirbagheri,Reza Vahab Kashani,Fateme Mehraban
Pajouhan Scientific Journal , 2013,
Abstract: Introduction: Foot deformities are common among complaints of patients referred to the orthopedic centers. Most of naturally occurring lower limb deformities in children, which are rather common, would be corrected with further normal growth. However, a small percentage of these problems remain unresolved and may cause complications in the future. The main aim of this study is determination of prevalence of flat foot and hallux valgus deformity among primary school female students in Kiar city of Chaharmahal and BakhtiariMaterial and Methods: This is a cross sectional study. Foot posture index (FPI 6) test evaluate for 345 students in age range 7- 11 years and two groups of 7 to 9 years and 11 to 10 years. Also prevalence of hallux valgus among 345 students evaluated.Results: 7.8 % of studied subjects had flat foot deformity. Among 345 students, 12 (6.6%) students in range of age 7 -9 years and 15 (9.3 %) students in range of 10-11 had flat foot deformity. Also prevalence of hallux valgus was 16.5%.Conclusion: These findings point to the importance of proper physical examination, early diagnosis and on-time treatment of foot deformities such as flat foot and hallux valgus deformity in children.
Attitude Control of a Flexible Satellite by Using Robust Control Design Methods  [PDF]
Reza Mohsenipour, Hossein Nemati, Mehrzad Nasirian, Abdolreza Kashani Nia
Intelligent Control and Automation (ICA) , 2013, DOI: 10.4236/ica.2013.43037
Abstract:

The increase of satellite’s dimensions has caused flexibility and formation of uncertainty in their model. This is because of space missions being more complex and using light moving structures in satellites. Satellites are also encountered with various circumferential disturbance torques. This uncertainty in model and disturbance torques will cause undesirable performance of satellites’ attitude control system. So, for attitude control of these satellites, those methods should be used which are robust to uncertainty of the plant’s model and can reject the effects of disturbances and the measurement noise. One of these methods is the robust control design method. But, because of pole’s place of these satellite’s dynamics equations, the designing procedure of robust control will face difficulties. In this paper, by using an internal feedback as a novel idea, the satellite’s dynamics equations are changed in such a way that the poles will be placed in proper locations. Then, for these new equations, by regarding the effects of flexibility as uncertainty and considering the uncertainty in inertia matrix of satellite, an Hcontroller has been designed and for better performance, a μ-controller has been improved. Afterwards, these two controllers are analyzed and compared for the original dynamic equations, not for the modified ones. Also, for comparison, a classic controller has been also designed for the original plant and eventually all these three controllers are compared with each other.

HYDATID CYST PRESENTING AS A THYROID NODULE:REPORT OF THREE CASES
Mohammad-Hassan Bastanhagh,Vahab Fatourechi,Reza Rajabian
Acta Medica Iranica , 1995,
Abstract: Hydatid cyst of the thyroid gland is rare, even in areas where echinococcosis is endemic. We report two cases of hydatid cyst of the thyroid gland and one case of a hydatid cyst in the soft tissues of the neck, in the latter, the cyst was superimposed on the thyroid gland and presented as a thyroid nodule. In one patient, fune needle aspiration biopsy produced severe anaphylaxis. In view of the rare occurrence of hydatid disease of the thyroid gland, fune needle aspiration biopsy of thyroid nodules can be performed routinely in areas enderric for echinococcosis but should be avoided if hydatid disease is strongly suspected.
A New Dual-Band Microstrip Antenna with U-Shaped Slot
Javad Ghalibafan;Amir Reza Attari;Farrokh Hojjat-Kashani
PIER C , 2010, DOI: 10.2528/PIERC10012706
Abstract: In this paper, we present a new dual band planar antenna. The proposed antenna consists of a microstrip patch with a U-shaped slot that is fed by a broadband electromagnetic coupling probe, known as L-probe. Radiation characteristics of the antenna and different methods for control of the resonant frequencies are investigated.
Analysis of Capasitively Coupled Microstrip-Ring Resonator Based on Spectral Domain Method
Reza Rezaiesarlak;Farrokh Hojjat-Kashani;Esfandiar Mehrshahi
PIER Letters , 2008, DOI: 10.2528/PIERL08012504
Abstract: In this paper, full-wave analysis of a microstrip-ring resonator capacitively coupled to Microstrip transmission line is presented. The method of the analysis is based on spectral domain in rectangular coordinate system. Since this coordinate system is not compatible with ring structure, triangular basis functions have been utilized for the current distributions on the ring surface. Applying Galerkin's method in spectral domain, the resonant frequencies of the structure and current distributions on the conductors are calculated and the effects of various parameters are studied. To verify the method of analysis, our results are compared with others and the accuracy of the method has been confirmed.
Full Wave Analysis of Two Layered Orthogonal Microstrip Transmission Lines Based on Spectral Domain Method
Reza Rezaiesarlak;Farrokh Hojjat-Kashani;Esfandiar Mehrshahi
PIER C , 2008, DOI: 10.2528/PIERC08012901
Abstract: In this paper, using moment method in the spectral domain, full wave analysis of two orthogonal microstrip transmission lines in two layered PCB board is presented. First, using 1-dimensional spectral domain method, the propagation constants and the currents on each line are obtained, without considering of the other line. Then, using Galerkine's method in 2 dimensional spectral domain, the scattering parameters of the structure are calculated. The results of our analysis are compared by the quasi-TEM approach. Comparisons show good agreement between our results and quasi-TEM approach.
A Broadband Quadrature Hybrid Using Improved Wideband Schiffman Phase Shifter
Eslam Jafari;Farrokh Hojjat-Kashani;Reza Rezaiesarlak
PIER C , 2009, DOI: 10.2528/PIERC09112101
Abstract: In this paper, a broadband quadrature hybrid is presented. The hybrid comprises a Wilkinson divider, followed by an improved Schiffman phase shifter. An improved wideband Schiffman phase shifter on a single layer printed circuit board is accompanied by a lumped capacitor between two coupled lines. Lumped capacitor is in parallel with the odd-mode capacitance of the two coupled lines, hence, the odd-mode capacitance is increased and consequently the odd-mode impedance is decreased. Therefore, by this method we can control the ratio of the even mode impedance to the odd mode impedance which is critical in Schiffman phase shifter design. Compared with the cascading Microstrip multi-section coupled lines, our proposed single layer phase shifter is smaller in size. Also, the proposed phase shifter has the greater bandwidth compared to the patterned ground plane Schiffman phase shifter and its realization is simpler because of its single layer structure. As an example, a Schiffman phase shifter at frequency =650 MHz is designed and simulated. With the proposed phase shifter a 90°hybrid is designed, simulated, fabricated and measured. Exprimental results show that the amplitude and phase imbalance between two paths at worth case are within 0.75 dB and 5°, respectively, over the frequency band from 362 MHz to 891 MHz, or around 84% bandwidth. The measured return loss is better than -10.8 dB over the operating frequency band.
Benzene-1,3-diammonium bis(pyridine-2,6-dicarboxylato-κ3O2,N,O6)cobaltate(II) pentahydrate
Hoda Pasdar,Saghi Sadat Kashani,Reza Ghiasi,Hossein Aghabozorg
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811009858
Abstract: In the title compound, (C6H10N2)[Co(C7H3NO4)2]·5H2O, the CoII ion is six-coordinated in an N2O4 environment by two pyridine-2,6-dicarboxylate (pydc) ligands, having a distorted octahedral geometry. The crystal packing is stabilized by intermolecular N—H...O, O—H...O and weak C—H...O hydrogen bonds. There are also π–π interactions between the pyridine rings of the pydc ligands and between the pydc ligands and the benzene-1,3-diammonium cations, with centroid–centroid distances of 3.4575 (15) and 3.7521 (15) .
Apoptosis of Rat Adipose-Derived Stem Cells during Transdifferentiation to Schwann-Like Cell
Zolikha Golipoor,Iraj Ragerdi Kashani,Mohammad Akbari,Reza Mahmoudi
Iranian Journal of Medical Sciences , 2010,
Abstract: Background: Adipose-derived stem cells (ADSCs) are a populationof pluripotent cells used for tissue engineering purposes.The main purpose of the present study was to transdifferentiatethe ADSCs to Schwann-like cells and to determine the intensityof apoptosis in ADSCs during the transdifferentiation process.Methods: ADSCs were isolated from the inguinal adiposetissue of adult rats and the identity of the undifferentiatedADSCs was confirmed by the detection of specific cells surfacemarkers. The ADSCs were transdifferentiated by sequentialadministration of beta mercaptoethanol, all-trans retinoicacid and a mixture of forskolin, beta fibroblast growth factor,platelet derived growth factor and hergulin. The immunocytochemicalproperties of transdifferentiated Schwann-like cellswere examined at specified time point. RT-PCR was used toinvestigate the gene expression of the undifferentiated andtransdifferentiated ADSCs. Cell apoptosis was assessed withannexin/propidium iodide staining and 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay.Results: Expression of Schwann cell marker S100 was determinedby immunocytochemical staining. RT-PCR analysesrevealed that the induced ADSCs exhibited Schwann cellspecificmarkers such as S-100, P75, and glial fibrillary acidicprotein on the 14th day. MTT assay and flow cytometry studiesshowed that of the total ADSCs in the differentiation medium,50% of the cells died by apoptosis, but the remainingcell population remained strongly attached to the substrate andcontinued to differentiate.Conclusion: ADSCs could differentiate to Schwann-like cells interms of morphology and phenotype. An increased cell death ratewas noted and the principle mode of cell death was apoptosis.Iran J Med Sci 2010; 35(2): 129-136.
The Effect of Posture Training Support Orthosis on Static Balance in Elderly Patients with Spinal Hyperkyphosis
Fatemeh Azadinia,Mojtaba Kamyab,Hamid Behtash,Reza Vaheb Kashani
Jundishapur Scientific Medical Journal , 2012,
Abstract: Background & Objective: Falls in the elderly are common and are associated with appreciable morbidity and mortality. Hyperkyphosis is a risk factor for balance impairment and postural instability. Increased forward curvature of the spine displaces the center of mass anteriorly out of the limits of stability, and thus increases the likelihood of loss of balance and predisposes persons to fall. The orthoses are an option for decreasing the risk of falling in elderly population; however, the quantitative evidence to support their application is not convincing. The purpose of this study is to analyze the effects of posture training support orthosis on static balance of elderly people with spinal hyperkyphosis.Subjects and Methods: Eighteen elderly people with the mean age of 65.96 ± 4.4 who had thoracic kyphosis of ≥ 50 (cobb angle) were enrolled in the study. Subjects were randomly allocated into either posture training support (PTS) orthosis or control group. Patients were randomly subjected to computerized dynamic posturography, which contained sensory organization tests and limits of stability. The tests for each person was conducted in two conditions: while wearing and without wearing the orthosis, and the order of testing for each patient was randomized.Results:Wearing PTS orthosis significantly increased balance score (p<0.0001), directional control (p=0.023) and reaction time(p=0.045). In addition, significant difference in balance score (p<0.0001) and directional control (p=0.041) was observed between two groups (PTS orthosis and control group).Conclusion:The PTS orthosis improves balance in elderly people with spinal hyperkyphosis. Improved balance could reduce the risk of falls and direct and indirect costs of falls and related fractures.
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