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Early initiation of antiretroviral treatment: Challenges in the Middle East and North Africa

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World Journal of Virology 2015年第2期4卷 134-141页

作者： Sara Sardashti Mehrnoosh Samaei Mona Mohammadi Firouzeh seyed Ali Mirshahvalad Fatemeh Golsoorat Pahlaviani seyed ahmad seyed alinaghi Iranian Research Center for HIV/AIDS Iranian Institute for Reduction of High Risk BehaviorsTehran University of Medical Sciences

New World Health Organization guidelines recommend the initiation of antiretroviral treatment(ART) for asymptomatic patients with CD4+ T-cell counts of ≤ 500 cells/mm3. Substantial reduction of human immunodeficiency virus(HIV) transmission is addressed as a major public health outcome of this new approach. Middle East and North Africa(MENA), known as the area of controversies in terms of availability of comprehensive data, has shown concentrated epidemics among most of it's at risk population groups. Serious challenges impede the applicability of new guidelines in the MENA Region. Insufficient resources restrict ART coverage to less than 14%, while only one fourth of the countries had reportable data on patients' CD4 counts at the time of diagnosis. Clinical guidelines need to be significantly modified to reach practical utility, and surveillance systems have not yet been developed in many countries of MENA. Based on available evidence in several countries people who inject drugs and men who have sex with men are increasingly vulnerable to HIV and viral hepatitis, while their sexual partners- either female sex workers or women in monogamous relationships with high-risk men- are potential bridging populations that are not appropriately addressed by regional programs. Research to monitor the response to ART among the mentioned groups are seriously lacking, while drug resistant HIV strains and limited information on adherence patterns to treatment regimens require urgent recognition by health policymakers. Commitment to defined goals in the fight against HIV, development of innovative methods to improve registration and reporting systems, monitoring and evaluation of current programs followed by costeffective modifications are proposed as effective steps to be acknowledged by National AIDS Programs of the countries of MENA Region.

关键词： Antiretroviral agents HIV CD4 counts Coinfections Regional health planning

New insights on the role of chondroitin sulfate proteoglycans in neural stem cell–mediated repair in spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1699-1700页

作者： seyed Mojtaba Hosseini Soheila Karimi-Abdolrezaee Department of Physiology and Pathophysiology Spinal Cord Research CentreRady Faculty of Health SciencesUniversity of ManitobaWinnipegMBCanada Manitoba Multiple Sclerosis Research Center WinnipegMBCanada Children Hospital Research Institute of Manitoba WinnipegMBCanada

Extensive neurodegeneration is a hallmark of traumatic spinal cord injury (SCI) that underlies permanent sensorimotor and autonomic impairments (Alizadeh et al.,2019).Following the primary impact,the spinal cord undergoes a cascade of secondary injury mechanisms that are driven by disruption of the blood-spinal cord ba rrier,vascula r inju ry,glial reactivity,neu roinfla mmation,oxidative stress,lipid peroxidation,and glutamate excitotoxicity that culminate in neuronal and oligodendroglial cell death,demyelination,and axonal damage(Alizadeh et al.,2019).To achieve a meaningful functional recovery after SCI,regeneration of new neurons and oligodendrocytes and their successful growth and integration within the neural network are critical steps for reconstructing the damaged spinal cord tissue (Fischer et al.,2020).

关键词： peroxidation Fischer injury

Hydrodynamic modeling strategy for dense to dilute gas-solid fluidized beds

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Particuology 2017年第2期15卷 105-116页

作者： seyed ahmad Kia Javad Aminian Faculty of Mechanical and Energy Engineering Shahid Beheshti University A.C. Tehran Iran

When investigating the hydrodynamic behavior of gas–solid flow systems, there are several options for the drag function, viscosity model, and other parameters. The low accuracy obtained with a random trial and error modeling strategy has led researchers to develop new drag models that are fine-tuned for their specific studies. However, besides the drag functions, an appropriate viscosity model together with radial distribution function have a great impact on the hydrodynamic modeling of fluidized beds. In this study, a detailed validation and verification task is conducted using three different experimental datasets to derive a modeling strategy for predicting hydrodynamic behavior in dense to dilute flow regimes of various fluidized beds. For this purpose, the steady-state Reynolds-averaged Navier–Stokes equations are solved in a finite volume scheme using the twoPhaseEulerFoam solver in the OpenFOAM 2.1.1 software. A comparative study of different drag and viscosity models enables an optimal modeling strategy to be determined for the accurate prediction of the bed pressure drop, bed expansion ratio, time-averaged solid hold-up, and bed height in various dense and dilute flow regimes. Our results show that the modeling strategy prescribed in this study is widely applicable for identifying the hydrodynamic characteristics of various gas–solid fluidized beds with different operating conditions.

关键词： Modeling strategy Hydrodynamic behavior Fluidized bed OpenFOAM Drag-viscosity model

An investigation on prevalent strategies for XFEM-based numerical modeling of crack growth in porous media

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 914-936页

作者： Mohammad REZANEZHAD seyed ahmad LAJEVARDI Sadegh KARIMPOULI Mining Engineering Group Faculty of EngineeringUniversity of ZanjanZanjan45371-38791Iran Materials Engineering Group Faculty of EngineeringUniversity of ZanjanZanjan45371-38791Iran

Crack growth modeling has always been one of the major challenges in fracture *** all numerical methods,the extended finite element method(XFEM)has recently attracted much attention due to its ability to estimate the discontinuous deformation ***,XFEM modeling does not directly lead to reliable results,and choosing a strategy of implementation is inevitable,especially in porous *** this study,two prevalent XFEM strategies are evaluated:a)applying reduced Young’s modulus to pores and b)using different partitions to the model and enriching each part *** mention the advantages and limitations of each strategy via both analytical and experimental ***,the crack growth is modeled in a natural porous media(Fontainebleau sandstone).Our investigations proved that although both strategies can identically predict the stress distribution in the sample,the first strategy simulates only the initial crack propagation,while the second strategy could model multiple cracks *** strategies are reliable and highly accurate in calculating the stress intensity factor,but the second strategy can compute a more reliable reaction *** tests showed that the second strategy is a more accurate strategy in predicting the preferred crack growth path and determining the maximum strength of the sample.

关键词： numerical modeling extended finite element method porous media crack growth stress intensity factor

Complete Moment Convergence for the Dependent Linear Processes with Random Coefficients

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Acta Mathematica Sinica,English Series 2019年第8期35卷 1321-1333页

作者： seyed Mohammad HOSSEINI ahmad NEZAKATI Faculty of Mathematical Sciences Shahrood University of Technology

In this paper, we investigate the complete moment convergence for dependent linear processes with random coefficients to form Xt =∑j^∞=∞ Aj∈t-j,where {∈n, n ∈ Z} is a sequence of END stochastically dominated random variables and {An,n ∈ Z} is a sequence of random varibles. As applications, the convergence rate, Marcinkiewicz-Zvgmund strong law and strong law of large numbers for this linear process are established.

关键词： Complete moment convergence ext ended negatively dependen t random variables linear processes random coefficients

Effect of ultrasonic irradiation on rheological properties of asphaltenic crude oils

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Petroleum Science 2012年第1期9卷 82-88页

作者： MOUSAVI seyed Mohammadreza RAMAZANI ahmad NAJAFI Iman DAVACHI seyed Mohammad Ultrasonic Research Group Chemical and Petroleum Engineering Department Sharif University of TechnologyAzadi Ave. Tehran Iran Chemical and Petroleum Engineering Department Sharif University of TechnologyAzadi Ave. Tehran Iran Ultrasonic Research Group Chemical and Petroleum Engineering Department Sharif University of Technology Azadi Ave. Tehran Iran Chemical and Petroleum Engineering Department Sharif University of Technology Azadi Ave. Tehran Iran

In this work, the rheological changes of several crude oil samples exposed to ultrasonic waves for different time intervals in addition to the effect of temperature on viscosity behavior of heavy crude oils were investigated using a series of steady shear flow and oscillatory tests. The colloidal structural evolutions of flocs in oil samples were illustrated by analysis of the size distribution of flocculated asphaltene particles （confocal microscopy tests）. The rheological investigations indicate that the ultrasonic irradiation dissolved heavy components in crude oil. After ultrasonic treatment, the Kouh-e-Mond crude oil was found to be pseudoplastic. In addition, confocal microscopy confirms that there was an optimum duration for ultrasonic irradiation, at which the viscosity and flocculation rate of asphaltenic crude oils reduced to the minimum values. The optimum was found to be approximately 40 min for the Kouh-e-Mond crude oil. Experimental results illustrate that the ultrasonic irradiation could disaggregate heavy colloid components in crude oil, and breakdown of asphaltene molecules would only occur in a specific time interval of irradiation. Also according to the temperature sweep test, the oil temperature rise caused by ultrasonic irradiation was not the main reason for theological changes of the crude oil and this alteration may be due to physical and chemical phenomena induced by sonication in crude oil.

关键词： Asphaltene ultrasonic technology pseudoplastic property viscoelastic property yield stress,flocculation time

Numerical Modelling Investigation of Wave Interaction on Composite Berm Breakwater

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China Ocean Engineering 2021年第5期35卷 631-645页

作者： seyed Morteza MARASHIAN Mehdi ADJAMI ahmad Rezaee MAZYAK Water and Environmental Engineering Department Faculty of Civil EngineeringShahrood University of TechnologyShahroodIran Faculty of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The breakwaters have experienced many changes during their construction *** changes have been considered to improve their performance,depending on their environmental conditions and *** modelling was conducted using FLOW-3 D *** this study,the wave overtopping from composite berm breakwater as new conceptual structure and the pressure imposed on the composite berm breakwater are considered and *** results show a decrease of 84.01,70.88 and 61.42 percent of the wave overtopping in the composite berm breakwater,in comparison to the rubble mound breakwater,horizontally caisson breakwater and caisson breakwater,***,the pressure applied to the composite berm breakwater with the pressure applied to the horizontally caisson breakwater was compared and *** berm breakwater compared with horizontally caisson breakwater in P1,the amount of the obtained pressure decreased by 52.09%,in P2 the amount of the obtained pressure decreased by 63.07%,in P3 decreased by 76.09%and in Pu,this pressure reduced by53.92%.For the composite berm breakwater,the impact of three types of berms,homogenous berm(Type 1),a berm consisting of armor-filter(Type 2)and multi-layer berm(Type 3)with the aim of optimizing the hydraulic responses and wave interaction on the caisson of the breakwater was examined and *** total,Type 3 will be recommended with a significant reduction in the overtopping values and maximum pressure.

关键词： composite berm breakwater wave interaction berm breakwater wave overtopping pressure rubble mound breakwater horizontally caisson breakwater caisson breakwater

Stratigraphical Study of the Taft Formation in the Bohruk Area from Yazd Block, Central Iran

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Journal of Earth Science 2015年第5期26卷 729-739页

作者： seyed ahmad Babazadeh Taiebeh Esmaeili Dehej Department of Science Payame Noor University

The Taft Formation is exposed at the Bohruk area from Yazd Block in central Iran with 136 m thickness comprising three informal members which are named, in ascending stratigraphical order named Lower, Middle and Upper members. The Lower and Upper members consist of bioclastic carbonate rocks, whereas the Middle Member contains two sub-members： carbonate and siliciclastic carbonate rocks. Four patterns of facies are recognized on the basis of field observation and microscopic study. They are grainstone facies, siliciclastic-carbonate facies, intermediate facies（grainstone-wackestone/packstone facies） and foraminiferal-clastic wackestone/packstone facies. Based on the facies associations, three facies belts are presented for the first time. Therefore, this formation was deposited on a shallow carbonate platform from the inner platform to rimmed platform. The main fauna of the Taft Formation include Istriloculina eliptica（Iovcheva）, Palorbitolina lenticularis（Blumenbach）, Charentia cuvillieri Neumann, Everticyclammina hedbergi（Maync）, Pseudocyclammina litus（Yokoyama）, Melathrokerion valserinensis Bronnimann ＆ Conrad, Nautiloculina oolithica Mohler, Glomospira urgoniana Arnaud Vanneau, Dicyclina schlumbergeri MunierChalmas, Derventina filipescui Neagu, Praechrysalidina infracretacea Luperto-Sinni, Pseudochoffatella cuvillieri Deloffre, Paracoskinolina sp., Textularia sp., and Lenticulina sp. Based on the foraminiferal distribution throughout the Taft Formation, two biozones like Istriloculina ellipticaPalorbitolina lenticularis zone and Glomospira urgoniana-Dicyclina schlumbergeri zone are recognized they and range from the Late Barremian to Early Albian in age.

关键词： Stratigraphy Taft Formation Central Iran Yazd Block Lower Cretaceous

Microstructure Modification of Powder Compact of Al-Zn-Mg Nanostructured Alloy by a Semisolid Thermomechanical Processing

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 39-45页

作者： Mohsen Hajizamani Mostafa Alizadeh seyed ahmad Jenabali-Jahromi Department of Metals Institute of Science and High Technology and Environmental SciencesGraduate University of Advanced Technology Department of Materials Science and Engineering School of EngineeringShiraz University

A thermomechanical process （TMP） consisting of three cycles of cold pressing at 154 MPa and liquid-phase sintering at 600 ℃ for 30 min in each cycle was applied to modify the microstructure of nanostructured A1-Zn-Mg alloy. The alloy powders were produced by mechanical alloying. Also, solid-state sintering at 550℃ for 90 min was done to compare the results with those obtained from the TMP. The powders and the thermomechanically （TM） processed samples were analyzed by XRD to reveal the present phases in addition to calculating the crystallite size changes by the Wil- liamson-Hall method. Moreover, scanning electron microscope was employed to observe the morphology of the powder and the microstructures of the sintered and the TM processed samples. The results revealed that the TMP affected the microstructure noticeably as well as the microhardness by removing the continuous grain boundary porosities and uniform distribution of the intermetallic phase particles as well as obtaining a near globular microstructure after the second cycle. Also, the average grain sizes in the first and the second cycles of the TMP were lower than those of the sintered sample. Furthermore, nanocrystalline grains were stable up to the second cycle of the TMP.

关键词： Thermomechanical processing AI-Zn-Mg alloy Intermetallics Sintering Grain growth