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Diagnostic Value of Dental Pulp Stones in the Early Diagnosis of Ischemic Heart Diseases

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Health 2015年第3期7卷 336-345页

作者： Fatemeh Ezoddini-Ardakani seyedeh Mahdieh Nemayandeh seyed Mahmood Sadrbafghi Sedigheh Hajihashemi Mahmood Emami Forouzandeh Ghasemi Kahtouei Leila Hadiani Mohammad hossein Ahmadieh Maliheh Moeini seyed hossein razavi Sajad Besharati Oral and Maxillofacial Radiology Department Faculty of Dentistry Shahid Sadoughi University of Medical Sci-ences Yazd Iran Yazd Cardiovascular Research Center Shahid Sadoughi University of Medical Sciences Yazd Iran Shahid Beheshti University of Medical Sciences Tehran Iran

Background: Pulp stones are calcified masses formed in the primary and permanent dentitions. The ischemic cardiovascular disorders (CVD) can be the first health problem of the world. It seems that there is a relationship between pulp stones and cardiovascular diseases to determine the diagnostic value of panoramic dental radiographs as non-invasive test for the early detection of CVD. Methods and Materials: The subjects of the study came from patients presenting to Dental Radiology Department of Dental School in Yazd who aged 30 - 64 years, had 8 natural teeth. They were referred to the Cardiovascular Center of Afshar Hospital in Yazd for cardiovascular evaluation. To set the cut-off point, the ratio of teeth with pulp stones to the total number of teeth for each person was calculated and also ABI for diagnosing IHD via ROC curve was used. Results: Only 3.8% of patients without pulp stone were affected by ischemic heart disease (IHD). About Sixty seven percent (67.3%) of individuals had at least one tooth with pulp stone. In individuals without IHD, 5% of the teeth showed pulp stone while this rate was 45% (9 times) in CVD patients. The number of patients for whom the ratio of teeth with pulp stone to total number of teeth was 0.2 or more, was 138.7 times greater than the other. Conclusion: The dentists, who order panoramic radiographs for the treatment of patients, exactly study those teeth for the presence of pulp stones. The ratio of teeth with pulp stone to total teeth equal 0.2 or more was a good tool for early detection of CVD.

关键词： Pulp Stone Cardiovascular Disease Panoramic Radiography

Comprehensive power swing detection by current signal modeling and prediction using the GMDH method

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Protection and Control of Modern Power Systems 2021年第1期6卷 204-214页

作者： seyed Amir hosseini Behrooz Taheri hossein Askarian Abyaneh Farzad razavi Department of Electrical Engineering Golpayegan University of TechnologyIsfahanIran Faculty of Electrical Biomedical and Mechatronics EngineeringQazvin BranchIslamic Azad UniversityQazvinIran Department of Electrical Engineering Amirkabir University of TechnologyTehranIran

Power swing is an undesirable variation in power flow. This can be caused by large disturbances in demand load, switching, disconnection or reclosing lines. This phenomenon may enter the zones of distance relays and cause relay malfunction leading to the disconnection of healthy lines and undermining network reliability. Accordingly, this paper presents a new power swing detection method based on the prediction of current signal with a GMDH (Group Method of Data Handling) artificial neural network. The main advantage of the proposed method over its counterparts is the immunity to noise effect in signals. In addition, the proposed method can detect stable, unstable, and multi-mode power swings and is capable of distinguishing them from the variety of permanent faults occurring simultaneously. The method is tested for different types of power swings and simultaneous faults using DIgSILENT and MATLAB, and compared with some latest power swing detection methods. The results demonstrate the superiority of the proposed method in terms of response time, the ability to detect power swings of different varieties, and the ability to detect different faults that may occur simultaneously with power swings.

关键词： Power swing Distance relay Power system protection GMDH

Numerical and Performance Analysis of one row Transonic Rotor with Sweep and Lean angle

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Journal of Thermal Science 2014年第5期23卷 438-445页

作者： seyed Reza razavi Masoud Boroom Aerospace Engineering Department AmirKabir University of Technology

In this study,aerodynamic behaviors of swept and leaned blades were *** and tangential blade curvatures impacts on compressor's operating parameters were analyzed separately.A commercial CFD program which solves the Reynolds-averaged Navier-Stokes equations was used to find out the mentioned impact and the complicated flow field of transonic *** CFD method that was used for solving flow field's equation was validated by experimental data of NASA Rotor *** results showed that the compressor with curved rotors had higher efficiency,rotor pressure ratio and stable operating range compared to the compressor with un-curved *** curved rotors mostly had higher impact on the overall stable operating range compared to the other operating *** range involves choking point and stall point that were changed separately by using of bended *** finding the detailed impact of sweep and lean angle on transonic blades,various forms of lean and sweep angles were exerted to basic *** was found that sweep angles increased overall operating range up to 30%,efficiency up to 2%and pressure ratio up to 1%.Leaning the blades increased the safe operating range,the pressure ratio and efficiency by 14%,4%and 2%respectively.

关键词： compressor performance efficiency stable operational range surge improvement swept Rotor leaned rotor

Correlation of the mean activity coefficient of aqueous electrolyte solutions using an equation of state

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Chinese Journal of Chemical Engineering 2016年第10期24卷 1456-1463页

作者： seyed hossein Mazloumi Chemical Engineering Department Faculty of EngineeringFerdowsi University of Mashhad

Accurate calculation of thermodynamic properties of electrolyte solution is essential in the design and optimization of many processes in chemical industries. A new electrolyte equation of state is developed for aqueous electrolyte solutions. The Carnahan-Starling repulsive model and an attractive term based on square-well potential are adopted to represent the short range interaction of ionic and molecular species in the new electrolyte EOS. The long range interaction of ionic species is expressed by a simplified version of Mean Spherical Approximation theory （MSA）. The new equation of state also contains a Born term for charging free energy of ions. Three adjustable parameters of new eEOS per each electrolyte solution are size parameter, square-well potential depth and square-well potential interaction range. The new eEOS is applied for correlation of mean activity coefficient and prediction of osmotic coefficient of various strong aqueous electrolyte solutions at 25℃ and 0.1 MPa. In addition, the extension of the new eEOS for correlation of mean activity coefficient and solution density of a few aqueous electrolytes at temperature range of 0 to 100℃ is carried out.

关键词： Aqueous electrolyte solution Electrolyte equation of state Activity coefficient Osmotic coefficient Solution density

Effect of residual structural strain caused by the addition of Co3O4 nanoparticles on the structural, hardness and magnetic properties of an Al/Co3O4 nanocomposite produced by powder metallurgy

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 384-390页

作者： seyed Rahim Kiahosseini hossein Ahmadian Department of Engineering Damghan Branch Islamic Azad University

Al composites are of interest due to their appropriate ratio of strength to *** our research,an Al/Co3O4 nanocomposite was generated using a sintering *** powders of Al with various Co3O4 nanoparticle contents(0 wt%,0.5 wt%,1.0 wt%,1.5 wt%,2.0 wt%,and2.5 wt%)were first blended using planetary milling for 30 min,and compressed in a cylindrical steel mold with a diameter of 1 cm and a height of5 cm at a pressure of 80 *** samples were evaluated with X-ray diffractometry(XRD),scanning electron microscopy(SEM),Vickers hardness,and a vibrating sample magnetometer(VSM).Although the crystallite size of the Al particles remained constant at 7–10 nm,the accumulation of nanoparticles in the Al particle interspace increased the structural tensile strain from 0.0045 to 0.0063,the hardness from HV 28 to HV 52 and the magnetic saturation from 0.044 to 0.404 emu/g with an increase in Co3O4 nanoparticle content from 0 wt%to 2.5 wt%.

关键词： Residual strain Vickers hardness vibrating sample magnetometer scanning electron microscopy

Enhanced microstructural and mechanical properties of Stellite/WC nanocomposite on Inconel 718 deposited through vibration-assisted laser cladding

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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 327-334页

作者： hossein hosseini-Tayeb seyed Mahdi Rafiaei Daneshpajoohan Pishro Higher Education Institute IsfahanIran Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayeganIsfahanIran

Stellite-21/WC nanopowders were deposited on Inconel through vibration-assisted laser cladding with different laser *** and scanning electron microscopy,hardness measurements,and wear characterizations were employed to understand the microstructural and mechanical behaviors of the *** showed that varying the cooling rate exerted remarkable effects on the microstructure of the as-cladded ***,increasing the laser power from 150 W to 250 W increased the heat input and the *** was affected by the scanning rate and powder feeding rate at a high laser power of 250 *** WC nanoparticles were added as reinforcement,the dilution magnitude intensified while the hardness value increased from HV 350 to HV *** wear characterizations indicated that the composites containing 3 wt%WC nanoparticles possessed the highest wear resistance.

关键词： Stellite WC nanoparticles mechanical properties laser cladding

Effects of turmeric(Curcuma longa)and its constituent(curcumin)on the metabolic syndrome:An updated review

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Journal of Integrative Medicine 2022年第3期20卷 193-203页

作者： Zeinab Vafaeipour Bibi Marjan razavi hossein hosseinzadeh Student Research Committee Mashhad University of Medical SciencesMashhad ***Iran Department of Pharmacodynamics and Toxicology School of PharmacyMashhad University of Medical SciencesMashhad ***Iran Targeted Drug Delivery Research Center Pharmaceutical Technology InstituteMashhad University of Medical SciencesMashhad ***Iran Pharmaceutical Research Center Pharmaceutical Technology InstituteMashhad University of Medical SciencesMashhad ***Iran

Metabolic syndrome(MS)involves people with the following risk factors:obesity,hypertension,high glucose level and *** can increase the risk of heart disease,stroke and type 2 diabetes *** prevalence of MS in the world’s adult population is about 20%–25%.Today,there is much care to use medicinal ***(Curcuma longa)as well as curcumin which is derived from the rhizome of the plant,has been shown beneficial effects on different components of ***,the purpose of this manuscript was to introduce different in vitro,in vivo and human studies regarding the effect of turmeric and its constituent on ***,different mechanisms of action by which this plant overcomes MS have been *** on studies,turmeric and its bioactive component,curcumin,due to their anti-inflammatory and antioxidant properties,have antidiabetic effects through increasing insulin release,antihyperlipidemic effects by increasing fatty acid uptake,anti-obesity effects by decreasing lipogenesis,and antihypertensive effects by increasing nitric *** to several in vivo,in vitro and human studies,it can be concluded that turmeric or curcumin has important values as a complementary therapy in ***,more clinical trials should be done to confirm these effects.

关键词： Turmeric Curcuma longa Curcumin Metabolic syndrome Diabetes Hyperlipidemia

Computational analysis of neutronic effects of ThO_2 rods loaded in CANDU 6 fuel assemblies

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Nuclear Science and Techniques 2016年第4期27卷 14-20页

作者： seyed Mohammad Mirvakili Zohreh Gholamzadeh seyed Amir hossein Feghhi Reactor Research School Nuclear Science and Technology Research Institute Department of Radiation Application Shahid Beheshti UniversityG.C

Thorium as a suitable fertile with higher natural resources in comparison with uranium resources has been remarkably considered by different nuclear energy user countries in the last decades. Its prominent features such as suitable possibility for power flattening of a nuclear reactor, applicable breeder blanket to produce^(233)U fissile as well as neutron leakage prevention from a nuclear core has caused its application as power flatter, breeder material or other aimed utilizations be evaluated by the researches. In the present study, neutronics of a modeled CANDU 6loaded with Th O_2 and UO_2fuel rods have been computationally studied. The study aimed at reprocessing of burned Th O_2 seeds at CANDU 6 reactor to recover the total produced uranium, which is to be going under another compound fuel cycle. The obtained results showed all the core reactivity coefficients are sufficiently negative. The modeled core 949 GWd burn-up concluding in 99.99 %depletion of^(235)U initial loads. 18.38 kg of^(233) U was produced in the burnt Th O_2 fuel after 1-year burn-up time. In addition, 31.84 kg of^(239) Pu was produced in the UO_2 spent fuel rods after the burn-up time. After a proposed cooling time, about 50.01 kg of^(233)U will be available in the spent Th O_2 fuel.

关键词： CANDU堆中子泄漏燃料组件稳定杆计算核反应堆燃烧时间自然资源

Design feasibility of gamma camera without collimator based on specific arrangement of the detectors

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Nuclear Science and Techniques 2016年第4期27卷 120-126页

作者： hossein Akbari-Lalimi seyed Ali Shafiei Geriatric Care Research Center Rafsanjan University of Medical Sciences Department of Medical Physics Mashhad University of Medical Sciences Department of Physiology and Pharmacology School of Medicine Qom University of Medical Sciences

In gamma camera and single-photon emission computerized tomography, the collimator removes most photons. Here, a gamma camera without collimator utilizes a specific arrangement of detectors. Instead of bending beams(like a lens) or directing beams(by parallel hole collimator), changes are created in detectors' field of view(FOV), so that each detector's FOV looks different from others. Simulation proved this theory, with 98 detectors(2 cm 9 1.41 cm) arranged in a zigzag manner for Monte Carlo simulation. A radioactive source with energy of140 ke V was situated on the detectors' faces. Sixty projections, each 3(0 –179) apart, were simulated by Monte Carlo N-Particle(MCNP) 4C code, rotating detectors around a radioactive point. The band containing the radioactive source is clearly visible in each *** obtained after simulation in different projections were reconstructed, and point source location emerged correctly. Simulation of gamma camera with zigzag arrangement of detectors and MCNP-4C code demonstrated that one could string the space and determine radioactive source by image reconstruction without using collimators, solely through these special detectors' distribution.

关键词：探测器准直器 γ相机蒙特卡洛模拟计算机断层扫描单光子发射设计布置