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Reliability of a patient survey assessing ＂Short Form Injury Questionnaire 7＂ in Iran

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Chinese Journal of Traumatology 2012年第3期15卷 145-147页

作者： mahdi sharif-Alhoseini Soheil Saadat Afarin Rahimi-movaghar Abbas motevalian masoumeh Amin-Esmaeili mitra Hefazi Vafa Rahimi-movaghar Sina Trauma and Surgery Research Center Tehran University of Medical Sciences Tehran 11365-3876 Iran Iranian Research Center for HIV/AIDS(IRCHA) Tehran University of Medical Sciences Tehran 11365-3876 Iran School of Public Health Tehran University of Medical Sciences Tehran 11365-3876 Iran

Objective： Injury is a major cause of morbidity and mortality in the world. The assessment of patterns and severity of injury in high-risk groups is crucial for planning and service development. On a large scale na- tional household survey, we estimated the annual incidence and the patterns of injury, the demographics of the injured people, as well as the service use for all injuries in Iran. The current study aims at assessing the reliability of the ques- tionnaire before carrying out a national survey. methods： In a pilot study using cluster random sam- pling approach, 73 people were interviewed. The interview- ers asked the participants to report all injuries occurred in them and the care provided during the previous 12 months, based on ＂Short Form Injury Questionnaire 7＂. About two weeks later, the interview was repeated by another interviewer. Results： In our test-retest reliability, Kappa score was good for three and moderate for four questions. The ques- tion on the injured organ had the highest test-retest reliabil- ity with a Kappa score of 0.84. Conclusions： The reliability of the questionnaire and the procedure of questioning are confirmed. The ques- tionnire is proper for utilization in large national surveies.

关键词： Injury severity score Reproducibility of results Iran

下丘脑-垂体-性腺轴抑制程度对中枢性性早熟女童成年预测身高的影响

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中国当代儿科杂志 2015年第10期17卷 1093-1097页

作者：陶月红曾碧荷沙里夫江苏省苏北人民医院儿科江苏扬州225001

目的研究促性腺激素释放激素类似物（Gn RHa）治疗过程中下丘脑-垂体-性腺轴（HPGA）抑制程度与中枢性性早熟（CPP）女童成年预测身高（PAH）的关系,以指导临床个体化调节GnRHa治疗剂量。方法收集75例CPP女童的临床资料,记录GnRHa治疗... 详细信息

目的研究促性腺激素释放激素类似物（Gn RHa）治疗过程中下丘脑-垂体-性腺轴（HPGA）抑制程度与中枢性性早熟（CPP）女童成年预测身高（PAH）的关系,以指导临床个体化调节GnRHa治疗剂量。方法收集75例CPP女童的临床资料,记录GnRHa治疗的不同时间点身高、骨龄（BA）、子宫卵巢容积及LH、FSH峰值、E2水平,计算各时间点PAH,分析PAH改善（ΔPAH=PAH-靶身高）的情况及其与HPGA抑制的关系,并采用阈值效应分析寻找ΔPAH的最佳HPGA抑制范围。结果 Gn RHa治疗后PAH较治疗初期有明显改善。ΔPAH与ΔBA呈负相关;治疗24月时ΔPAH与LH呈负相关。将子宫容积控制在2.3～3.0 m L之间,LH控制在0.8 IU/L以下,FSH控制在2.4 IU/L以下对延缓BA的增长及改善PAH有利。结论 GnRHa治疗能改善CPP女童的PAH。选择合适的Gn RHa治疗剂量,将子宫容积、LH、FSH控制在一定范围内,有利于延缓BA及改善PAH。

关键词：促性腺激素释放激素类似物中枢性性早熟下丘脑-垂体-性腺轴成年预测身高儿童

Effect of ECAP temperature on microstructure and mechanical properties of Al–Zn–mg–Cu alloy

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Progress in Natural Science:materials International 2016年第2期26卷 182-191页

作者： m.H.Shaeri m.Shaeri m.Ebrahimi m.T.Salehi S.H Seyyedein Department of metallurgy and materials Engineering Engineering Faculty Imam Khomeini International University Department of materials Science and Engineering Sharif University of Technology Department of mechanical Engineering University of Maragheh Department of metallurgy and materials Engineering Iran University of Science and Technology

The effect of equal channel angular pressing(ECAP) at different temperatures(room temperature, 120,150 and 180 °C) on microstructure and mechanical properties of Al-7075 solid solution alloy was investigated. microstructure of the specimens was examined using orientation imaging microscopy,transmission electron microscopy as well as X-ray diffractometer, and mechanical properties were measured by Vickers microhardness and tensile tests. microstructural investigations showed that after3 or 4 passes of ECAP, fi ne grains with average grain sizes in range of 300–1000 nm could be obtained at different ECAP temperatures. Increasing ECAP temperature from 120 to 180 °C caused a decrease in mechanical properties as a result of increasing grains and precipitates sizes, decreasing fraction of high angle boundaries and also transformation of η′ into η phase, while increasing ECAP temperature from RT to 120 °C leads to an increase in mechanical properties due to the formation of small η′ precipitates. So it can be concluded that ECAP process at 120 °C is the optimum process for attaining maximum mechanical properties. Quantitative estimates of various strengthening mechanisms revealed that the improvement of mechanical properties was mainly attributed to grain re fi nement strengthening, precipitation strengthening and dislocation strengthening.

关键词： Equal channel angular pressing microstructure Strengthening mechanisms mechanical properties

Experimental study on correlation between turbulence and sound in a subsonic wind tunnel

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Acta mechanica Sinica 2010年第4期26卷 531-539页

作者： m.D.manshadi K.Ghorbanian m.R.Soltani Department of Aerospace Engineering Sharif University of Technology

In this paper, the effects of turbulence on sound generation and velocity fluctuations due to pressure waves in a large subsonic wind tunnel are studied. A trip strip located at different positions in the contraction part or at one position in the diffuser of a large wind tunnel is used to investigate the aforementioned phenomenon, and the results indicate that the trip strip has significant effects on sound reduction. The lowest turbulence intensity and sound are obtained from a trip strip with a diameter of 0.91 mm located either at X/L = 0.79 or at X/L = 0.115 in the wide portion of the contraction. Furthermore, the effect of monopole, dipole and quadrupole sources of aerodynamic noise at different velocities is investigated, and it is demonstrated that the contribution of the monopole is dominant, while the shares due to the dipole and quadrupole remain less important. In addition, it is found that the sound waves have a modest impact on the measured longitudinal turbulence and are generated essentially by eddies.

关键词： Wind tunnel. Turbulence Sound Quadrupole term - Correlation

multidimensional modeling of the stenosed carotid artery: A novel CAD approach accompanied by an extensive lumped model

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Acta mechanica Sinica 2014年第2期30卷 259-273页

作者： A.Kashefi m.mahdinia B.Firoozabadi m.Amirkhosravi G.Ahmadi m.S.Saidi Department of mechanical Engineering Sharif University of Technology Department of mechanical Engineering University of California Berkeley Faculty of Engineering Department of Mechanical EngineeringSharif University of Technology Faculty of Engineering Department of Mechanical and Aeronautical EngineeringClarkson University

This study describes a multidimensional 3D/lumped parameter（LP） model which contains appropriate inflow/outflow boundary conditions in order to model the entire human arterial trees. A new extensive LP model of the entire arterial network（48 arteries） was developed including the effect of vessel diameter tapering and the parameterization of resistance, conductor and inductor variables. A computer aided-design（CAD） algorithm was proposed to effciently handle the coupling of two or more 3D models with the LP model, and substantially lessen the coupling processing time. Realistic boundary conditions and Navier-Stokes equations in healthy and stenosed models of carotid artery bifurcation（CAB） were used to investigate the unsteady Newtonian blood flow velocity distribution in the internal carotid artery（ICA）. The present simulation results agree well with previous experimental and numerical studies. The outcomes of a pure LP model and those of the coupled 3D healthy model were found to be nearly the same in both cases. Concerning the various analyzed 3D zones, the stenosis growth in the ICA was not found as a crucial factor in determining the absorbing boundary *** paper demonstrates the advantages of coupling local and systemic models to comprehend physiological diseases of the cardiovascular system.

关键词： Hemodynamic 3D/LP coupling CAD Realis-tic boundary conditions Carotid artery bifurcation Stenosis

Effect of equal channel angular pressing on aging treatment of Al-7075 alloy

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Progress in Natural Science:materials International 2015年第2期25卷 159-168页

作者： m.H.Shaeri m.Shaeri m.T.Salehi S.H.Seyyedein m.R.Abutalebi Department of metallurgy and materials Engineering Engineering Faculty Imam Khomeini International University Department of materials Science and Engineering Sharif University of Technology Department of metallurgy and materials Engineering Iran University of Science and Technology (IUST)

The effect of aging treatment on microstructure and mechanical properties of equal channel angular pressed Al-7075 alloy was *** Al-7075 alloy in the solid solution heat-treated condition was processed by equal channel angular pressing through route BCat both the room temperature and 120 1C. Only three passes of equal channel angular pressing was possible due to the low ductility of the alloy at both temperatures. Followed by equal channel angular pressing, the specimens have been aged at 120 1C for different aging times. mechanical properties were measured by Vickers microhardness and tensile tests and microstructural observations were undertaken using transmission electron microscopy, X-ray diffractometer as well as optical microscopy. microstructural investigations showed that ultrafine-grained materials with grain size in the range of 200–350 nm and 300–500 nm could be obtained after three passes of equal channel angular pressing at room temperature and 120 1C, respectively. Equal channel angular pressing of solid solution heat-treated Al-7075 alloy accelerates precipitation rate and subsequently leads to a significant decrease in aging time to attain maximum mechanical properties. Furthermore, it is possible to achieve maximum mechanical properties during equal channel angular pressing at 120 1C as a result of dynamic aging and formation of small η′ phase.

关键词： Equal channel angular pressing Grain refinement Aging treatment TEm mechanical properties

Steady Lateral Growth of Three-Dimensional Particle Laden Density Currents

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China Ocean Engineering 2018年第4期32卷 467-475页

作者： m.R.moossavi Hekmati m.Najafi N.Ashrafi khorasani Department of mechanical and Aerospace Engineering Science and Research Branch Islamic Azad University

In this paper the steady lateral growth of three-dimensional turbulent inclined turbidity current is investigated. To simulate the current, an experimental setup is developed to analyze the turbidity current for different regimes in the particle laden density currents environment. The Buckingham’s π theorem together with a dimensional analysis is implemented to derive the appropriate non-dimensional variables. The experimental results were normalized and plotted in the form of non-dimensional graphs from which a theoretical model is developed and analyzed. Based on the results obtained for the steady lateral growth, three different regimes, namely, inertia-viscous one as the first regime, buoyancy-viscous and gravity-viscous as the second and third regimes are distinguished within the *** these regimes, the force balance is between the driving and resisting forces. Namely, in the first regime, the force balance is between the inertia and viscous forces, in the second regime, the buoyancy and viscous forces, and in the third regime, gravity and viscous forces are balanced. The experimental results indicate that the lateral growth rate in the first regime is smaller than that in the second and third regimes due to the magnitude and type of the forces involved in those regimes. According to the graphical results, the three different lateral growth rates appear when the normalized current length is smaller than about 3, between about 3 and 10, and larger than about 10. In those regions,the slopes of the data are different with respect to one another.

关键词： turbidity current steady particle lateral growth turbulence supercritical initial conditions

Comparative analysis of different static mixers performance by CFD technique:An innovative mixer

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Chinese Journal of Chemical Engineering 2020年第3期28卷 672-684页

作者： m.m.Haddadi S.H.Hosseini D.Rashtchian martin Olazar Chemical and Petroleum Engineering Department Sharif University of TechnologyTehranIran Department of Chemical Engineering.Ilam University llam 69315-516Iran Department of Chemical Engineering University of the Basque Country(UPV/EHU)Sarriena s/nLeioaSpain

The flow and mixing behavior of two miscible liquids has been studied in an innovative static mixer by using CFD,with Reynolds numbers ranging from 20 to *** performance of the new mixer is compared with those of Kenics,SmX,and Komax static *** pressure drop ratio(Z-factor),coefficient of variation(CoV),and extensional efficiency(α)features have been used to evaluate power consumption,distributive mixing,and dispersive mixing performances,respectively,in all *** model is firstly validated based on experimental data measured for the pressure drop ratio and the coefficient of *** results are consistent with measured data and those obtained by available correlations in the *** new mixer shows a superior mixing performance compared to the other mixers.

关键词： CFD New static mixer Coefficient of variation Pressure drop ratio

New turbulence modeling for air/water stratified flow

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Journal of Ocean Engineering and Science 2020年第1期5卷 55-67页

作者： m.Ghafari m.B.Ghofrani Department of Energy Engineering Sharif University of TechnologyAzadi Ave.TehranIran

The prediction of interfacial turbulence characteristics is one of the still challenging of two-phase stratified *** evaluation of some important parameters such as interfacial heat transfer coefficient based on turbulence kinetic energy and turbulence dissipation rate in some models,intensifies the importance of turbulence flow correct *** gradient of velocity and turbulence kinetic energy at the interface of two-phase stratified flow leads to a major overestimation or underestimation of flow characteristics without any special *** of a source function of turbulence eddy frequency at the interface is one of the common solution employed in past *** this solution remedies some shortcomings of traditional methods in smooth stratified flow,its application in wavy stratified flow needs the other *** examination of turbulence characteristics near the free surface reveals that,in addition to turbulence eddy frequency,the other source function of turbulence kinetic energy should be considered near the free ***,a new source function of turbulence kinetic energy is proposed at the interface based on flow *** new method has been employed for Fabre et al.(1987)experiment designed for air/water stratified *** results of simulation have a good agreement with experimental data and turbulence characteristic can be captured near the free surface.

关键词： Stratified flow Turbulence model Turbulence kinetic energy Source function