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Carbon nanotubes in cancer therapy: A more precise look at the role of carbon nanotube-polymer interactions
, Article Chemical Society Reviews ; Volume 42, Issue 12 , Feb , 2013 , Pages 5231-5256 ; 03060012 (ISSN) ; Soleyman, R ; Beiranvand, Z ; Madani, F ; Sharif University of Technology
2013
Abstract
Despite the great potential of carbon nanotubes (CNTs) in various areas of biomedicine, concerns regarding their carcinogenicity, inefficient dispersion in aqueous solutions and biological activity in vivo still remain. One important and feasible route to overcome these barriers is modification of CNTs with polymers, which are widely studied and play a vital role in biological and biomedical fields, especially in drug delivery. This comprehensive review focuses on the achievements of our and other groups in currently used methods to functionalize the surface of CNTs with polymers to produce anticancer drug delivery systems. We have intensively studied covalent and noncovalent interactions...
Graphene: Promises, facts, opportunities, and challenges in nanomedicine
, Article Chemical Reviews ; Volume 113, Issue 5 , 2013 , Pages 3407-3424 ; 00092665 (ISSN) ; Laurent, S ; Chen, W ; Akhavan, O ; Imani, M ; Ashkarran, A. A ; Mahmoudi, M ; Sharif University of Technology
2013
Abstract
Graphene, a two-dimensional (2D) sheet of sp2-hybridized carbon atoms packed into a honeycomb lattice, has led to an explosion of interest in the field of materials science, physics, chemistry, and biotechnology since the few-layers graphene (FLG) flakes were isolated from graphite in 2004. For an extended search, derivatives of nanomedicine such as biosensing, biomedical, antibacterial, diagnosis, cancer and photothermal therapy, drug delivery, stem cell, tissue engineering, imaging, protein interaction, DNA, RNA, toxicity, and so on were also added. Since carbon nanotubes are normally described as rolled-up cylinders of graphene sheets and the controllable synthesis of nanotubes is well...
Polymeric mixed matrix membranes containing zeolites as a filler for gas separation applications: A review
, Article Journal of Industrial and Engineering Chemistry ; Volume 19, Issue 2 , 2013 , Pages 375-393 ; 1226086X (ISSN) ; Esmaeili, N ; Asadollahi, M ; Sharif University of Technology
2013
Abstract
Polymeric membrane technology has received extensive attention in the field of gas separation, recently. However, the tradeoff between permeability and selectivity is one of the biggest problems faced by pure polymer membranes, which greatly limits their further application in the chemical and petrochemical industries. To enhance gas separation performances, recent works have focused on improving polymeric membranes selectivity and permeability by fabricating mixed matrix membranes (MMMs). Inorganic zeolite materials distributed in the organic polymer matrix enhance the separation performance of the membranes well beyond the intrinsic properties of the polymer matrix. This concept combines...
Conductive polymer-based microextraction methods: A review
, Article Analytica Chimica Acta ; Volume 767, Issue 1 , March , 2013 , Pages 1-13 ; 00032670 (ISSN) ; Ayazi, Z ; Naderi, M ; Sharif University of Technology
2013
Abstract
Conductive polymers (CPs) are classified as materials which exhibit highly reversible redox behavior and the unusual combined properties of metal and plastics. CPs, due to their multifunctionality, ease of synthesis and their stability, have attracted more attentions in different fields of research, including sample preparation. CPs along with several commercial hydrophilic sorbents, are alternative to the commercially available hydrophobic sorbents which despite their high specific surface areas, have poor interactions and retentions in the extraction of polar compounds. This review covers a general overview regarding the recent progress and new applications of CPs toward their synthesis...
A decision tool for accelerated bridge construction
, Article PCI Journal ; Volume 58, Issue 2 , 2013 , Pages 48-63 ; 08879672 (ISSN) ; Emami, S ; Doolen, T. L ; Tang, B ; Sharif University of Technology
2013
Abstract
Accelerated bridge construction is recognized as an important method for bridge owners to accelerate the delivery of highway bridge projects. While the potential advantages of accelerated bridge construction are recognized, it is difficult for transportation specialists to quantify the risks and benefits of using accelerated bridge construction compared with conventional construction for specific bridge replacement or rehabilitation projects. A tool set, based on the analytic hierarchy process, is prepared for transportation specialists and decision makers to determine whether accelerated bridge construction is more effective than traditional construction for a given bridge replacement or...
A replenishment policy for perishable products with non-linear holding cost under stochastic supply lead time
, Article International Journal of Advanced Manufacturing Technology ; Volume 64, Issue 5-8 , 2013 , Pages 1087-1098 ; 02683768 (ISSN) ; Baboli, A ; Akbari Jokar, M. R ; Sharif University of Technology
2013
Abstract
The development and application of inventory models for deteriorating items is one of the main concerns of subject matter experts. The inventory models developed in this field have focused mainly on supply chains under the assumption of constant lead time. In this study, we develop an inventory model for a main class of deteriorating items, namely perishable products, under stochastic lead time assumption. The inventory system is modeled as a continuous review system (r, Q). Demand rate per unit time is assumed to be constant over an infinite planning horizon and the shortages could be backordered completely. For modeling the deterioration process, a non-linear holding cost is considered....
A hybrid method of fuzzy simulation and genetic algorithm to optimize constrained inventory control systems with stochastic replenishments and fuzzy demand
, Article Information Sciences ; Volume 220 , 2013 , Pages 425-441 ; 00200255 (ISSN) ; Niaki, S. T. A ; Aryanezhad, M. B ; Shafii, N ; Sharif University of Technology
2013
Abstract
Multi-periodic inventory control problems are mainly studied by employing one of two assumptions. First, the continuous review, where depending on the inventory level, orders can happen at any time, and next the periodic review, where orders can only be placed at the beginning of each period. In this paper, we relax these assumptions and assume the times between two replenishments are independent random variables. For the problem at hand, the decision variables (the maximum inventory of several products) are of integer-type and there is a single space-constraint. While demands are treated as fuzzy numbers, a combination of back-order and lost-sales is considered for the shortages. We...
Low back pain and postural sway during quiet standing with and without sensory manipulation: A systematic review
, Article Gait and Posture ; Volume 37, Issue 1 , 2013 , Pages 12-22 ; 09666362 (ISSN) ; Coenen, P ; Parnianpour, M ; Kiers, H ; van Dieen, J. H ; Sharif University of Technology
2013
Abstract
A previous review concluded that postural sway is increased in patients with low back pain (LBP). However, more detailed analysis of the literature shows that postural deficit may be dependent on experimental conditions in which patients with LBP have been assessed. The research question to be answered in this review was: " Is there any difference in postural sway between subjects with and without LBP across several sensory manipulation conditions?" A literature search in Pubmed, Scopus, Embase and PsychInfo was performed followed by hand search and contact with authors. Studies investigating postural sway during bipedal stance without applying external forces in patients with specific and...
Position control of shape memory alloy actuator based on the generalized Prandtl-Ishlinskii inverse model
, Article Mechatronics ; Volume 22, Issue 7 , 2012 , Pages 945-957 ; 09574158 (ISSN) ; Zakerzadeh, M. R ; Sharif University of Technology
2012
Abstract
Hysteresis and significant nonlinearities in the behavior of Shape Memory Alloy (SMA) actuators encumber effective utilization of these actuator. Due to these effects, the position control of SMA actuators has been a great challenge in recent years. Literature review of the research conducted in this area shows that using the inverse of the phenomenological hysteresis models can compensate the hysteresis of these actuators effectively. But, inverting some of these models, such as Preisach model, is numerically a complex task. However, the generalized Prandtl-Ishlinskii model is analytically invertible, and therefore can be implemented conveniently as a feedforward controller for compensating...
A framework to review performance prism
, Article International Journal of Operations and Production Management ; Volume 32, Issue 10 , 2012 , Pages 1124-1146 ; 01443577 (ISSN) ; Etebari, M ; Emami, S ; Sharif University of Technology
2012
Abstract
Purpose: The purpose of this paper is to develop an exclusive review framework for the Performance Prism. Design/methodology/approach: An extensive literature survey on performance measurement is used to identify the main aspects of the review in such systems. Various dimensions related to the characteristics of Performance Prism are explored. All the findings are then rationally put together to develop the proposed conceptual framework. Findings: The paper presents a conceptual model to review performance measurement systems (PMS) which are designed based on Performance Prism. The presented framework categorizes review processes and tools into two main categories; Business Performance...
Towards greater mechanical, thermal and chemical stability in solid-phase microextraction
, Article TrAC - Trends in Analytical Chemistry ; Volume 34 , 2012 , Pages 126-138 ; 01659936 (ISSN) ; Piri-Moghadam, H ; Naderi, M ; Sharif University of Technology
Abstract
Solid-phase microextraction (SPME) is a fast, solvent-free technique, which, since its introduction in the 1990s, has been increasingly applied to sample preparation in analytical chemistry. Conventional SPME fibers are fabricated by making a physical bond between the usual silica substrate and the polymeric coatings. However, some applications are limited, as the lifetime and the stability of conventional SPME fibers cannot meet the demands of analyzing relatively non-volatile compounds with more polar moieties. There have been attempts to analyze less volatile compounds by increasing the thermal, physical and chemical stability of the fibers. In this review, we present some new...
Is independent component analysis appropriate for multivariate resolution in analytical chemistry?
, Article TrAC - Trends in Analytical Chemistry ; Volume 31 , 2012 , Pages 134-143 ; 01659936 (ISSN) ; Jalali Heravi, M ; Tauler, R ; Sharif University of Technology
2012
Abstract
In this article, we examine Independent Component Analysis (ICA) and the concept of Mutual information (MI) as a quantitative measure of independence from the point of view of analytical chemistry. We compare results obtained by different ICA methods with results obtained by Multivariate Curve Resolution Alternating Least Squares (MCR-ALS). These results have shown that, when non-negativity constraints are applied, values of MI increase considerably and the resolved components cannot anymore be considered to be independent (i.e. they can only be considered to be the " least dependent" components). MI values of profiles resolved by MCR-ALS and ICA did not differ significantly when...
Ranking of technology transfer barriers in developing countries; case study of Iran's biotechnology industry
, Article IEEE International Conference on Industrial Engineering and Engineering Management, 6 December 2011 through 9 December 2011, Singapore ; 2011 , Pages 1602-1606 ; 21573611 (ISSN) ; 9781457707391 (ISBN) ; Rashvanlouei, K. Y ; Ismail, K ; Sharif University of Technology
Abstract
In this paper, first we shall define a list of technology transfer barriers in the biotechnology field through interviews and literature reviews. Next, we shall categorize them into four major categories of technology, and at last introduce all of the hypotheses on the existence of relationship between each part of technology and failure in the technology transfer process. Questionnaires consisting of two parts were created and handed out to all of the specialists and biotechnology idea-holders in the Iranian National Research center of Biotechnology, Lidco Co, Iran Pastor Institute, Biotechnology Department of University of Tehran, etc. Going on, we've evaluated the factors' validity...
Protein-nanoparticle interactions: Opportunities and challenges
, Article Chemical Reviews ; Volume 111, Issue 9 , June , 2011 , Pages 5610-5637 ; 00092665 (ISSN) ; Lynch, I ; Ejtehadi, M. R ; Monopoli, M. P ; Bombelli, F. B ; Laurent, S ; Sharif University of Technology
2011
Abstract
The significant role of protein nanoparticle interactions in nanomedicine and nanotoxicity is emerging recently through the identification of the nanoparticles (NP) protein (biomolecule) corona. The dynamic layer of proteins and/or other biomolecules adsorbed to the nanoparticle surface determines how a NP interacts with living systems and thereby modifies the cellular responses to the NP. Ehrenberg and co-workers used cultured endothelium cells as a model for vascular transport of polystyrene NP with various functional groups, which showed that the capacity of the various NP surfaces to adsorb proteins was indicative of their tendency to associate with cells. The quantification of the...
A parameter-tuned genetic algorithm to optimize two-echelon continuous review inventory systems
, Article Expert Systems with Applications ; Volume 38, Issue 9 , September , 2011 , Pages 11708-11714 ; 09574174 (ISSN) ; Niaki, S. T. A ; Tokhmehchi, N ; Sharif University of Technology
2011
Abstract
This paper deals with a two-echelon inventory system for a non-repairable item where the system consists of one warehouse and m identical retailers and uses continuous-review (R, Q) ordering policy. To find an effective stocking policy for this system, a mathematical model with the objective of minimizing the total annual inventory investment subject to constraints on the average annual order frequency, expected number of backorders, and budget is formulated. The mathematical model of the problem at hand is shown to be nonlinear integer-programming and hence a parameter-tuned genetic algorithm is proposed to solve it efficiently. A numerical example is provided at the end to illustrate the...
Recent trends in application of multivariate curve resolution approaches for improving gas chromatography-mass spectrometry analysis of essential oils
, Article Talanta ; Volume 85, Issue 2 , 2011 , Pages 835-849 ; 00399140 (ISSN) ; Parastar, H ; Sharif University of Technology
2011
Abstract
Essential oils (EOs) are valuable natural products that are popular nowadays in the world due to their effects on the health conditions of human beings and their role in preventing and curing diseases. In addition, EOs have a broad range of applications in foods, perfumes, cosmetics and human nutrition. Among different techniques for analysis of EOs, gas chromatography-mass spectrometry (GC-MS) is the most important one in recent years. However, there are some fundamental problems in GC-MS analysis including baseline drift, spectral background, noise, low S/N (signal to noise) ratio, changes in the peak shapes and co-elution. Multivariate curve resolution (MCR) approaches cope with ongoing...
Experimental investigation of air-water, two-phase flow regimes in vertical mini pipe
, Article Scientia Iranica ; Volume 18, Issue 4 B , August , 2011 , Pages 923-929 ; 10263098 (ISSN) ; Saidi, M. H ; Nouri Gheimasi, A ; Ghanbarzadeh, S ; Sharif University of Technology
2011
Abstract
In this study, the flow patterns of air-water, two-phase flows have been investigated experimentally in a vertical mini pipe. The flow regimes were observed by a high speed video recorder in pipes with diameters of 2,3 and 4 mm and length 27, 31 and 25 cm, respectively. The comprehensive visualization of air-water, two-phase flow in a vertical mini pipe has been performed to realize the physics of such a two-phase flow. Different flow patterns of air-water flow were observed simultaneously in the mini pipe at different values of air and water flow rates. Consequently, the flow pattern map was proposed for flow in the mini-pipe, in terms of superficial velocities of liquid and gas phases. The...
Determination of the economical policy of a three-echelon inventory system with (R, Q) ordering policy and information sharing
, Article International Journal of Advanced Manufacturing Technology ; Volume 55, Issue 5-8 , 2011 , Pages 831-841 ; 02683768 (ISSN) ; Sajadifar, S. M ; Haji, R ; Sharif University of Technology
2011
Abstract
In this work, we consider a three-echelon serial inventory system with two warehouses (suppliers) and one retailer with information exchange. The retailer applies continuous review (R, Q) policy. The warehouses have online information on the inventory position and demand activities of the retailer. We present a new ordering policy to share information among inventory echelons. The warehouse I and II start with m 1 and m 2 initial batches of the same order size of the retailer, respectively. The warehouse I places an order to an outside source immediately after the retailer's inventory position reaches an amount equal to the retailer's order point plus a fixed value s 1, and the warehouse II...
Development of a continuous kinetic model for visbreaking reactions
, Article Scientia Iranica ; Volume 18, Issue 3 C , 2011 , Pages 465-469 ; 10263098 (ISSN) ; Khosravani, L ; Khorasheh, F ; Sharif University of Technology
2011
Abstract
In this study the kinetic modeling of visbreaking reactions for a number of vacuum residue feeds was investigated using available experimental data from the literature. A continuous lumping model was developed for kinetic analysis of visbreaking reactions. The normalized boiling point was used to describe each feed as a continuous mixture and the concentration distribution of the mixture would change under reaction conditions. A continuous model with five adjustable parameters was used to describe visbreaking reactions, and these parameters were optimized for each feed for reaction temperatures in the range of 400-430 C using available experimental data. The model was able to accurately...
Computer modeling of drug distribution after intravitreal administration
, Article World Academy of Science, Engineering and Technology ; Volume 77 , 2011 , Pages 706-716 ; 2010376X (ISSN) ; Abdekhodaie, M. J ; Cheng, Y. L ; Saadatmand, M ; Sharif University of Technology
2011
Abstract
Intravitreal injection (IVI) is the most common treatment for eye posterior segment diseases such as endopthalmitis, retinitis, age-related macular degeneration, diabetic retinopathy, uveitis, and retinal detachment. Most of the drugs used to treat vitreoretinal diseases, have a narrow concentration range in which they are effective, and may be toxic at higher concentrations. Therefore, it is critical to know the drug distribution within the eye following intravitreal injection. Having knowledge of drug distribution, ophthalmologists can decide on drug injection frequency while minimizing damage to tissues. The goal of this study was to develop a computer model to predict intraocular...