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    A novel metabolic disorder in the degradation pathway of endogenous methanol due to a mutation in the gene of alcohol dehydrogenase

    , Article Clinical Biochemistry ; Volume 90 , 2021 , Pages 66-72 ; 00099120 (ISSN) Razzaghy Azar, M ; Nourbakhsh, M ; Vafadar, M ; Nourbakhsh, M ; Talebi, S ; Sharifi Zarchi, A ; Salehi Siavashani, E ; Garshasbi, M ; Sharif University of Technology
    Elsevier Inc  2021
    Abstract
    Background: A small amount of methanol is produced endogenously in the human body but it is efficiently metabolized by alcohol dehydrogenase (ADH) and other enzymes, and the products eliminated without harm. In this study, we present a new entity of inborn error of methanol metabolism due to a mutation in the ADH1C gene coding for the γ subunit that is part of several ADH isoenzymes. Results: This disorder was discovered in an 11.58-year-old boy. During one 9-month hospital admission, he had periods of 1–4 days during which he was comatose, and between these periods he was sometimes verbose and euphoric, and had ataxia, dysarthria. Following hemodialysis treatments, he became conscious and... 

    A latency-tolerant MAC protocol for underwater acoustic sensor networks

    , Article ICCAS 2010 - International Conference on Control, Automation and Systems, 27 October 2010 through 30 October 2010, Gyeonggi-do ; 2010 , Pages 849-854 ; 9781424474530 (ISBN) Azar, Z ; Manzuri, M. T ; Sharif University of Technology
    2010
    Abstract
    Wireless networks with the shared media require Medium Access Control (MAC) protocol that provides contention resolution mechanism. The design of MAC protocol in underwater sensor networks is a challenging issue because of limited energy source and high propagation delay. The most important goal of the MAC design for underwater sensor networks is to resolve data packet collision efficiently with respect to energy consumption. So, selection of MAC protocol is an important task because it has significant impact on the system efficiency. A suitable MAC protocol must consider some factors such as fairness, energy consumption, latency and throughput based on various applications. The bandwidth in... 

    Robust-fuzzy model for supplier selection under uncertainty: an application to the automobile industry

    , Article Scientia Iranica ; Volume 25, Issue 4 , 2018 , Pages 2297-2311 ; 10263098 (ISSN) Rabieh, M ; Modarres, M ; Azar, A ; Sharif University of Technology
    Sharif University of Technology  2018
    Abstract
    This paper proposes an innovative robust-fuzzy method for multi-objective, multi-period supplier selection problem under multiple uncertainties. This approach integrates robust optimization and fuzzy programming. Uncertain parameters are modeled as random variables that take value within a symmetrical interval. However, due to the complexity or ambiguity of some real world problems and especially the nature of some of the available input data, the length of interval is also highly uncertain. This ambiguity motivated us to present a new approach, which could be applicable to multiple uncertainties conditions. Thus, in our approach, the half-length of these intervals is also represented by... 

    Compound triple jets film cooling improvements via velocity and density ratios: Large eddy simulation

    , Article Journal of Fluids Engineering, Transactions of the ASME ; Volume 133, Issue 3 , Mar , 2011 ; 00982202 (ISSN) Farhadi Azar, R ; Ramezanizadeh, M ; Taeibi Rahni, M ; Salimi, M ; Sharif University of Technology
    2011
    Abstract
    The flow hydrodynamic effects and film cooling effectiveness placing two small coolant ports just upstream the main jet (combined triple jets) were numerically investigated. Cross sections of all jets are rectangular and they are inclined normally into the hot cross-flow. The finite volume method and the SIMPLE algorithm on a multiblock nonuniform staggered grid were applied. The large-eddy simulation approach with three different subgrid scale models was used. The obtained results showed that this flow configuration reduces the mixing between the freestream and the coolant jets and hence provides considerable improvements in film cooling effectiveness (both centerline and spanwise averaged... 

    Film cooling effectiveness enhancement applying another jet in the upstream neighbor of the main jet-using LES approach

    , Article Journal of Applied Fluid Mechanics ; Volume 9, Issue 1 , 2016 , Pages 33-42 ; 17353572 (ISSN) Salimi, M. R ; Ramezanizadeh, M ; Taeibi Rahni, M ; Farhadi Azar, R ; Sharif University of Technology
    Isfahan University of Technology  2016
    Abstract
    Flow hydrodynamic effects and film cooling effectiveness of placing a coolant port (upstream jet) just upstream of the main cooling jet were numerically investigated. The upstream jet was added such that the total cooling cross section (cross sections of the main and upstream jets) remains constant, in comparison to the case of ordinary cooling jet. The finite volume method and the unsteady SIMPLE algorithm on a multi- block non-uniform staggered grid arrangement were applied. The large eddy simulation (LES) approach with the one equation subgrid scale model was used. The jet to cross flow velocity ratio (for both of the main and the upstream jets) is 0.5 and the cross flow Reynolds number... 

    P-V-L Deep: A big data analytics solution for now-casting in monetary policy

    , Article Journal of Information Technology Management ; Volume 12, Issue 4 , 2021 , Pages 22-62 ; 20085893 (ISSN) Sarduie, M. H ; Kazemi, M. A ; Alborzi, M ; Azar, A ; Kermanshah, A ; Sharif University of Technology
    University of Tehran  2021
    Abstract
    The development of new technologies has confronted the entire domain of science and industry with issues of big data's scalability as well as its integration with the purpose of forecasting analytics in its life cycle. In predictive analytics, the forecast of near-future and recent past - or in other words, the now-casting - is the continuous study of real-time events and constantly updated where it considers eventuality. So, it is necessary to consider the highly data-driven technologies and to use new methods of analysis, like machine learning and visualization tools, with the ability of interaction and connection to different data resources with varieties of data regarding the type of big... 

    Integrated seismic attributes to characterize a widely distributed carbonate clastic deposit system in khuzestan province, SW Iran

    , Article Journal of Geophysics and Engineering ; Volume 6, Issue 2 , 2009 , Pages 162-171 ; 17422132 (ISSN) Hassanzadeh Azar, J ; Nabi Bidhendi, M ; Javaherian, A ; Pishvaie, M. R ; Sharif University of Technology
    2009
    Abstract
    Integrated seismic attributes, coherency, acoustic impedance (AI), lambda-rho (λρ) and mu-rho (μρ), were used to delineate and to characterize a complex regional channel deposition system in a carbonate reservoir interval in the upper part of the Sarvak Formation. The study area incorporates three adjacent oil fields in SW Iran (Khuzestan Province) covered by three individual 3D seismic surveys having a total area of about 2800 km 2. We generated a regional horizon-based coherency cube using these three seismic surveys. This revealed a carbonate clastic deposition channelling system over the entire study area. We characterized this channel deposition system in agreement with regional... 

    An approach to defining tortuosity and cementation factor in carbonate reservoir rocks

    , Article Journal of Petroleum Science and Engineering ; Volume 60, Issue 2 , 2008 , Pages 125-131 ; 09204105 (ISSN) Hassanzadeh Azar, J ; Javaherian, A ; Pishvaie, M. R ; Nabi Bidhendi, M ; Sharif University of Technology
    2008
    Abstract
    Tortuosity and cementation factor are two critical parameters that significantly affect estimates of reservoir properties. Tortuosity factor can be used to estimate permeability using the Carman-Kozeny equation and is an important parameter for formation resistivity factor calculation using a modified version of Archie's formula. It is also used to predict water saturation of reservoir rocks. Tortuosity as an input parameter in Biot's equation can be used to estimate velocity dispersion. In this work, based on the Generalized Archie Equation Curve Fitting (GAECF), tortuosity and cementation factor are determined for selected intervals in a carbonate reservoir. Formation resistivity factor... 

    Interplay between geometrical structure and electronic properties in rippled free-standing graphene

    , Article Physical Review B - Condensed Matter and Materials Physics ; Volume 83, Issue 16 , 2011 ; 10980121 (ISSN) Partovi Azar, P ; Nafari, N ; Tabar, M. R. R ; Sharif University of Technology
    2011
    Abstract
    It has been argued that the electron-hole puddles formed on graphene are mostly due to substrate-induced charged impurities. Here, using first-principles ab initio calculations, we show that the existence of ripples and electron-hole puddles is indeed an intrinsic property of graphene at finite temperatures. We found a relatively large correlation between the electronic charge density distribution on the surface of graphene and its local geometrical properties, such as local mean curvature and average bond length. We show that the electron and hole puddles appear in places where curvatures are large and small, respectively. We also determined the average sizes of the observed electron-hole... 

    Surface/edge functionalized boron nitride quantum dots: Spectroscopic fingerprint of bandgap modification by chemical functionalization

    , Article Ceramics International ; Volume 46, Issue 1 , 2020 , Pages 978-985 Angizi, S ; Shayeganfar, F ; Hasanzadeh Azar, M ; Simchi, A ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    Promising properties of boron nitride nanomaterials such as their chemical, thermal, and mechanical stability have made them suitable materials in a various range of applications. However, their low electrical conductivity and wide bandgap, particularly in the case of boron nitride quantum dots (BNQDs), have given rise to severe limitations. Efforts on bandgap engineering through doping and surface functionalization have gained little success due to their high thermodynamic stability and inertness. Herein, we present a novel approach to functionalize BNQDs by hydroxyl, methyl, and amine functional groups aiming to adjust the electronic structure. The successful exfoliation is demonstrated by... 

    Analytical investigation of composite sandwich beams filled with shape memory polymer corrugated core

    , Article Meccanica ; Volume 54, Issue 10 , 2019 , Pages 1647-1661 ; 00256455 (ISSN) Akbari Azar, S ; Baghani, M ; Zakerzadeh, M. R ; Shahsavari, H ; Sohrabpour, S ; Sharif University of Technology
    Springer Netherlands  2019
    Abstract
    Shape memory polymers (SMPs) are a class of smart materials which can recover their shape even after many shape changes in application of an external stimulus. In this paper, flexural behavior of a composite beam, constructed of a corrugated part filled with SMPs, is studied. This composite beam is applicable in sensor and actuator applications. Since the corrugated profiles display higher stiffness-to-mass ratio in the transverse to the corrugation direction, the beams with a corrugated part along the transverse direction are stiffer than ones with a corrugated part along the length. Employing a developed constitutive model for SMPs and the Euler–Bernoulli beam theory, the behavior of the... 

    Self-assembly, stability, and photoresponse of PbS quantum dot films capped with mixed halide perovskite ligands

    , Article Materials Research Bulletin ; Volume 147 , 2022 ; 00255408 (ISSN) Aynehband, S ; Mohammadi, M ; Poushimin, R ; Azar, M. H ; Nunzi, J. M ; Simchi, A ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    The type of passivating ligands and the ligand exchange method influence the quality of lead sulfide quantum dot films. This imparts on the efficiency of optoelectronic devices. To get a compact arrangement of the nanocrystals in a thin film (⁓100 nm) via self-assembling, we used organic-inorganic perovskites with mixed halides for the solid-state exchange of oleic acid ligands on PbS QDs (⁓ 4 nm). Formamidinium lead halides FAPbIxBr3-x (x= 3,2,1,0) were used. X-ray spectroscopy shows that successful replacement of oleic acid with FA happens by short immersion of the films (2 min) in the solution. Transmission electron microscopy shows that nano-scale cracks, short-range ordering, and fusion... 

    An intelligent model of transparent governance in policymaker organizations with the approach of good governance

    , Article Journal of Information Technology Management ; Volume 12, Issue 1 , 2020 , Pages 43-66 Sepehrnia, R ; Alborzi, M ; Kermanshah, A ; Azar, A ; Sepehrnia, R ; Sharif University of Technology
    University of Tehran  2020
    Abstract
    The new paradigm of good governance has an emphasis on international transparency, and this in this study takes into account the actual impacts of organizational intelligence in policymaker organizations. This study primarily aims to design an intelligent model of transparent governance in policymaker organizations with the approach of good governance. The study is a fundamental research in terms of objectives. In the qualitative section, data collection was done through Delphi interview questions, and the statistical population was senior managers, specialists, and policymakers with targeted sampling. In the quantitative part, the population was mid-level managers and organizational... 

    Elevated-temperature behaviour of LiNi0.5Co0.2Mn0.3O2 cathode modified with rGO-SiO2 composite coating

    , Article Journal of Alloys and Compounds ; Volume 843 , 2020 Razmjoo Khollari, M. A ; Khalili Azar, M ; Esmaeili, M ; Tanhaei, M ; Dolati, A ; Hosseini H, S. M ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    An intense decrease in cycling performance and safety is a challenge for elevated temperature application of LiNi0.5Co0.2Mn0.3O2 (NCM) cathode material. In this paper, effect of two types of nano-coatings on improvement of elevated temperature performance of NCM cathode material has been investigated. One of the coatings contains SiO2 nanoparticles and the other one contains composite of reduced graphene oxide and SiO2 nanoparticles (rGO-SiO2). The coatings were fabricated by a facile wet chemical method. The SiO2 coated cathode material showed an excellent elevated temperature cycling stability, however, a decrease in discharge capacity and rate capability of this sample was observed. On... 

    Symmetric and asymmetric bimanual coordination and freezing of gait in Parkinsonian patients in drug phases

    , Article Annals of the New York Academy of Sciences ; Volume 1511, Issue 1 , 2022 , Pages 244-261 ; 00778923 (ISSN) Fathipour Azar, Z ; Azad, A ; Akbarfahimi, M ; Behzadipour, S ; Taghizadeh, G ; Sharif University of Technology
    John Wiley and Sons Inc  2022
    Abstract
    Freezing of gait (FOG) is a debilitating symptom in patients with Parkinson's disease (PD), which may be associated with motor control impairments in tasks other than gait. This study aimed to examine whether symmetric and asymmetric bimanual coordination is impaired in PD with FOG (PD +FOG) patients and whether dual-task and drug phases may affect bimanual coordination in these patients. Twenty PD +FOG patients, 20 PD patients without FOG (PD –FOG) performed symmetric and asymmetric functional bimanual tasks (reach to and pick up a box and open a drawer to press a pushbutton inside it, respectively) under single-task and dual-task conditions. PD patients were evaluated during on- and... 

    Semi-empirical modelling of hydraulic conductivity of clayey soils exposed to deionized and saline environments

    , Article Journal of Contaminant Hydrology ; Volume 249 , 2022 ; 01697722 (ISSN) Hedayati Azar, A ; Sadeghi, H ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Clay liners are widely used as porous membrane barriers to control solute transport and to prevent the leakage of leachate both in horizontal and vertical flow scenarios, such as the isolated base and ramps of sanitary landfills. Despite the primary importance of saturated hydraulic conductivity in a reliable simulation of fluid flow through clay barriers, there is no model to predict hydraulic conductivity of clayey soils permeated with saline aqueous solutions because most of the current models were developed for pure water. Therefore, the main motivation behind this study is to derive semi-empirical models for simulating the hydraulic conductivity of clayey soils in the presence of... 

    Theoretical and numerical study of contaminant transport in clayey barriers using a revised numerical model considering the dependency of membrane efficiency and hydraulic conductivity on solute concentration

    , Article Heliyon ; Volume 9, Issue 5 , 2023 ; 24058440 (ISSN) Sadeghi, H ; Hedayati Azar, A ; Sharif University of Technology
    Elsevier Ltd  2023
    Abstract
    Solid waste is often buried in landfills isolated with a bentonite-based clay barrier to guarantee the high quality of groundwater. As the efficiency of clay barriers is highly dependent on solute concentration, this study aims to modify membrane efficiency, effective diffusion, and hydraulic conductivity of bentonite-based clayey barriers exposed to saline environments for numerical investigation of solute transport in such barriers. Therefore, the theoretical equations were modified as a function of solute concentration instead of constant values. First, a model was extended for membrane efficiency as a function of void ratio and solute concentration. Second, an apparent tortuosity model... 

    Synergistic role of carbon nanotube and SiCn reinforcements on mechanical properties and corrosion behavior of Cu-based nanocomposite developed by flake powder metallurgy and spark plasma sintering process

    , Article Materials Science and Engineering A ; Volume 786 , 2020 Akbarpour, M. R ; Mousa Mirabad, H ; Khalili Azar, M ; Kakaei, K ; Kim, H .S ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    Hybrid-reinforced metals are novel composite materials in which nano-phases including nanoparticles and nanotubes/nanosheets are used simultaneously to reinforce metals or alloys to enhance physical, mechanical, wear and other properties. In this research, Cu/(CNT-SiC) hybrid nanocomposite was synthesized using flake powder metallurgy and spark plasma sintering method and the effects of hybrid reinforcements on microstructural, wear and corrosion properties of the developed material were investigated and compared with those of copper. Microstructural characterization showed reduction of average grain size from 419 to 307 nm and increase of low angle grain boundaries with the introduction and... 

    Effect of silica encapsulation on the stability and photoluminescence emission of FAPbI3 nanocrystals for white-light-emitting perovskite diodes

    , Article Journal of Alloys and Compounds ; Volume 907 , 2022 ; 09258388 (ISSN) Hasanzadeh Azar, M ; Mohammadi, M ; Tabatabaei Rezaei, N ; Aynehband, S ; Simchi, A ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    The α-FAPbI3 perovskite nanocrystals exhibit interesting optical properties, which make them attractive for versatile optoelectronic applications; however, the spontaneous phase transformation to the non-perovskite phase (δ-FAPbI3) in humid conditions requires a new strategy to improve the phase stability of the material. We employed 3-Aminopropyl triethoxysilane (APTES)-assisted reprecipitation and sol-gel methods at ambient temperature to prepare stable α-FAPbI3 nanocrystals embedded in a silica matrix. Transmission electron microscopy (TEM) and X-ray diffraction analysis determined that ultrafine perovskite nanocrystals (11.5 ± 3 nm) were uniformly distributed in a silica matrix.... 

    L-sorbose production by gluconobacter oxydans using submerged fermentation in a bench scale fermenter

    , Article Applied Food Biotechnology ; Volume 7, Issue 1 , 2020 , Pages 41-48 Alizad Derakhshi Azar, S ; Alemzadeh, I ; Sharif University of Technology
    National Nutrition and Food Technology Research Institute  2020
    Abstract
    Background and objective: L-Sorbose, as a precursor of ascorbic acid, can be biologically produced using Gluconobacter oxydans. The aim of this study was to optimize production of L-Sorbose by controlling concentration of the substrates and starter cultures. Material and methods: In this study, effects of three various fermentation parameters on the concentration of L-sorbose were assessed using fermenter (28°C, 1.4 vvm) and response surface methodology. These parameters included quantities of D-sorbitol (120-180 g lDw-1) (Deionized water) and yeast extract (6-18 g lDw-1) and inoculum/substrate ratios (5-10%). Results and conclusion: Results showed that the fitted model with high values of...