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    Silver nanoparticles with gelatin nanoshells: Photochemical facile green synthesis and their antimicrobial activity

    , Article Journal of Nanoparticle Research ; Volume 13, Issue 10 , October , 2011 , Pages 4647-4658 ; 13880764 (ISSN) Pourjavadi, A ; Soleyman, R ; Sharif University of Technology
    In the current study, a facile green synthesis of silver-gelatin core-shell nanostructures (spherical, spherical/cubic hybrid, and cubic, DLS diameter: 4.1-6.9 nm) is reported via the wet chemical synthesis procedure. Sunlight-UV as an available reducing agent cause mild reduction of silver ions into the silver nanoparticles (Ag-NPs). Gelatin protein, as an effective capping/shaping agent, was used in the reaction to self-assemble silver nanostructures. The formation of silver nanostructures and their self-assembly pattern was confirmed by SEM, AFM, and TEM techniques. Further investigations were carried out using zeta-potential, UV-Vis, FTIR, GPC, and TGA/DTG/DTA data. The prepared Ag-NPs... 

    Potential of Calendula alata for phytoremediation of stable cesium and lead from solutions

    , Article Environmental Monitoring and Assessment ; Volume 181, Issue 1-4 , Oct , 2011 , Pages 63-68 ; 01676369 (ISSN) Borghei, M ; Arjmandi, R ; Moogouei, R ; Sharif University of Technology
    Calendula alata plants were tested for their potential to remove stable cesium and lead from solutions in a 15-day period. The plants were grown hydroponically and placed in solutions containing CsCl and Pb(C 2H 3O 2)2 at different concentrations (0.6, 2 and 5 mg l-1). When plants were incubated in CsCl solutions 46.84 ± 2.12%, 41.35 ± 1.59%, and 52.06 ± 1.02% cesium was found to be remediated after 15 days. Moreover, more than 99% lead was removed from the Pb(C 2H 3O 2)2solution in all three concentrations after 15 days during the same period. When both CsCl and Pb(C 2H 3O 2)2were supplemented together in the solution, 9.92 ± 1.22%, 45.56 ± 3.52%, and 46.16 ± 1.48% cesium and 95.30 ± 0.72%,... 

    Phytoremediation of stable Cs from solutions by Calendula alata, Amaranthus chlorostachys and Chenopodium album

    , Article Ecotoxicology and Environmental Safety ; Volume 74, Issue 7 , October , 2011 , Pages 2036-2039 ; 01476513 (ISSN) Moogouei, R ; Borghei, M ; Arjmandi, R ; Sharif University of Technology
    Uptake rate of 133Cs, at three different concentrations of CsCl, by Calendula alata, Amaranthus chlorostachys and Chenopodium album plants grown outdoors was studied. These plants grow abundantly in semi-arid regions and their varieties exist in many parts of the world. When exposed to lowest Cs concentration 68 percent Cs was remediated by Chenopodium album. 133Cs accumulation in shoots of Amaranthus chlorostachys reached its highest value of 2146.2mgkg -1 at a 133Cs supply level of 3.95mgl -1 of feed solution. The highest concentration ratio value was 4.89 for Amaranthus chlorostachys, whereas for the other tests it ranged from 0.74 to 3.33. Furthermore uptake of 133Cs by all three species... 

    Analysis of Iranian rosemary essential oil: Application of gas chromatography-mass spectrometry combined with chemometrics

    , Article Journal of Chromatography A ; Volume 1218, Issue 18 , May , 2011 , Pages 2569-2576 ; 00219673 (ISSN) Jalali Heravi, M ; Moazeni, R. S ; Sereshti, H ; Sharif University of Technology
    This paper focuses on characterization of the components of Iranian rosemary essential oil using gas chromatography-mass spectrometry (GC-MS). Multivariate curve resolution (MCR) approach was used to overcome the problem of background, baseline offset and overlapping/embedded peaks in GC-MS. The analysis of GC-MS data revealed that sixty eight components exist in the rosemary essential oil. However, with the help of MCR this number was extended to ninety nine components with concentrations higher than 0.01%, which accounts for 98.23% of the total relative content of the rosemary essential oil. The most important constituents of the Iranian rosemary are 1,8-cineole (23.47%), α-pinene... 

    Real-time simulation of the nonlinear visco-elastic deformations of soft tissues

    , Article International Journal of Computer Assisted Radiology and Surgery ; Volume 6, Issue 3 , 2011 , Pages 297-307 ; 18616410 (ISSN) Basafa, E ; Farahmand, F ; Sharif University of Technology
    Purpose: Mass-spring-damper (MSD) models are often used for real-time surgery simulation due to their fast response and fairly realistic deformation replication. An improved real time simulation model of soft tissue deformation due to a laparoscopic surgical indenter was developed and tested. Method: The mechanical realization of conventional MSD models was improved using nonlinear springs and nodal dampers, while their high computational efficiency was maintained using an adapted implicit integration algorithm. New practical algorithms for model parameter tuning, collision detection, and simulation were incorporated. Results: The model was able to replicate complex biological soft tissue... 

    Compound Hertzian chain model for copper-carbon nanocomposites' absorption spectrum

    , Article Micro and Nano Letters ; Volume 6, Issue 4 , 2011 , Pages 277-279 ; 17500443 (ISSN) Kokabi, A ; Hosseini, M ; Saeedi, S ; Moftakharzadeh, A ; Vesaghi, M. A ; Fardmanesh, M ; Sharif University of Technology
    The infrared range optical absorption mechanism of carbon-copper composite thin layer coated on the diamond-like carbon buffer layer has been investigated. By consideration of weak interactions between copper nanoparticles in their network, optical absorption is modelled using their coherent dipole behaviour induced by the electromagnetic radiation. The copper nanoparticles in the bulk of carbon are assumed as a chain of plasmonic dipoles, which have coupling resonance. Considering nearest neighbour interactions for this metallic nanoparticles, surface plasmon resonance frequency (ω 0) and coupled plasmon resonance frequency (ω 1) have been computed. The damping rate against wavelength is... 

    A study of Acidithiobacillus Ferrooxidans DSMZ 583 Adaptation to Heavy Metals

    , Article Iranian Journal of Biotechnology ; Volume 9, Issue 2 , 2011 , Pages 133-144 ; 17283043 (ISSN) Yaghmaei, S ; Ghobadi, Z ; Sharif University of Technology
    In this study the ability of Acidithiobacillus ferrooxi-dans, with regard to the biorecovery of heavy metals in shake flask has been investigated. Adaptation experiments with the single metal ions Ni, Co, V, Mo, W and a mixture of the first four metal ions in the medium was developed through serial sub-culturing. Adaptation showed that A. ferrooxidans could tolerate up to 2.3 g/l Ni, 1.4 g/l Co, 1.4 g/l V, 0.045 g/l Mo and 0.005 g/l W, singly. In the presence of multi-metals considering a mixture of Ni-Co-V-Mo, the bacteria was able to tolerate up to 1.5 g/l Ni, 0.8 g/l Co, 0.8 g/l V and 0.05 g/l Mo in steps of 50-100 mg/l for Ni, Co and V, while for Mo and W with increments in concentration... 

    Design and Synthesis of Novel Polyglycerol Hybrid Nanomaterials for Potential Applications in Drug Delivery Systems

    , Article Macromolecular Bioscience ; Volume 11, Issue 3 , NOV , 2011 , Pages 383-390 ; 16165187 (ISSN) Zarrabi, A ; Adeli, M ; Vossoughi, M ; Shokrgozar, M. A ; Sharif University of Technology
    The synthesis of a new drug delivery system based on hybrid nanomaterials containing a β-CD core and hyperbranched PG is described. Conjugating PG branches onto β-CD not only increases its water solubility but also affects its host/guest properties deeply. It can form molecular inclusion complexes with small hydrophobic guest molecules such as ferrocene or FITC with reasonable release. In addition, the achievable payloads are significantly higher as for carriers such as hyperbranched PGs. Short-term in vitro cytotoxicity and hemocompatibility tests on L929 cell lines show that the hybrid nanomaterial is highly biocompatible. Due to their outstanding properties, β-CD-g-PG hybrid nanomaterials... 

    Recent progress in inorganic and composite coatings with bactericidal capability for orthopaedic applications

    , Article Nanomedicine: Nanotechnology, Biology, and Medicine ; Volume 7, Issue 1 , Feb , 2011 , Pages 22-39 ; 15499634 (ISSN) Simchi, A ; Tamjid, E ; Pishbin, F ; Boccaccini, A. R ; Sharif University of Technology
    This review covers the most recent developments of inorganic and organic-inorganic composite coatings for orthopedic implants, providing the interface with living tissue and with potential for drug delivery to combat infections. Conventional systemic delivery of drugs is an inefficient procedure that may cause toxicity and may require a patient's hospitalization for monitoring. Local delivery of antibiotics and other bioactive molecules maximizes their effect where they are required, reduces potential systemic toxicity and increases timeliness and cost efficiency. In addition, local delivery has broad applications in combating infection-related diseases. Polymeric coatings may present some... 

    Preparation and biological evaluation of radiolabeled-folate embedded superparamagnetic nanoparticles in wild-type rats

    , Article Journal of Radioanalytical and Nuclear Chemistry ; Volume 287, Issue 1 , January , 2011 , Pages 119-127 ; 02365731 (ISSN) Jalilian, A. R ; Hosseini Salekdeh, S. L ; Mahmoudi, M ; Yousefnia, H ; Majdabadi, A ; Pouladian, M ; Sharif University of Technology
    In this study, superparamagnetic iron oxide nanoparticles (SPION) embedded by folic acid (SPION-folate) were prepared by a modified co-precipitation method. The structure, size, morphology, magnetic property and relaxivity of the SPION-folate were characterized systematically by means of XRD, VSM, HRSEM and TEM and the interaction between folate and iron oxide (Fe3O 4) was characterized by FT-IR. The particle size was shown to be ≈5-10 nm. To ensure biocompatibility, the interaction of these SPION with mouse connective tissue cells (adhesive) was investigated using an MTT assay. Consequently, gallium-67 labeled nanoparticles ([67Ga]-SPION-folate) were prepared using 67Ga with a high labeling... 

    Superparamagnetic iron oxide nanoparticles (SPIONs): Development, surface modification and applications in chemotherapy

    , Article Advanced Drug Delivery Reviews ; Volume 63, Issue 1-2 , January–February , 2011 , Pages 24-46 ; 0169409X (ISSN) Mahmoudi, M ; Sant, S ; Wang, B ; Laurent, S ; Sen, T ; Sharif University of Technology
    At present, nanoparticles are used for various biomedical applications where they facilitate laboratory diagnostics and therapeutics. More specifically for drug delivery purposes, the use of nanoparticles is attracting increasing attention due to their unique capabilities and their negligible side effects not only in cancer therapy but also in the treatment of other ailments. Among all types of nanoparticles, biocompatible superparamagnetic iron oxide nanoparticles (SPIONs) with proper surface architecture and conjugated targeting ligands/proteins have attracted a great deal of attention for drug delivery applications. This review covers recent advances in the development of SPIONs together... 

    Interactive optimization of biosurfactant production by Paenibacillus alvei ARN63 isolated from an Iranian oil well

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 82, Issue 1 , 2011 , Pages 33-39 ; 09277765 (ISSN) Najafi, A. R ; Rahimpour, M. R ; Jahanmiri, A. H ; Roostaazad, R ; Arabian, D ; Soleimani, M ; Jamshidnejad, Z ; Sharif University of Technology
    The potential of an indigenous bacterial strain isolated from an Iranian oil field for the production of biosurfactant was investigated in this study. After isolation, the bacterium was characterized to be Paenibacillus alvei by biochemical tests and 16S ribotyping. The biosurfactant, which was produced by this bacterium, was able to lower the surface tension of media to 35. mN/m. Accordingly, thin layer chromatography (TLC) and FT-IR has been carried out to determine compositional analysis of the produced biosurfactant. After all the tests related to characterization of the biosurfactant produced by the isolated bacterium, it was characterized as lipopeptide derivative. The combination of... 

    The role of co-solvents in improving the direct transesterification of wet microalgal biomass under supercritical condition

    , Article Bioresource Technology ; Volume 193 , October , 2015 , Pages 90-96 ; 09608524 (ISSN) Abedini Najafabadi, H ; Vossoughi, M ; Pazuki, G ; Sharif University of Technology
    Elsevier Ltd  2015
    In this research, direct conversion of wet algal biomass into biodiesel using supercritical methanol was studied. In this process, microalgal lipids simultaneously was extracted and converted to biodiesel under high pressure and temperature conditions without using any catalyst. Several experiments have been performed to optimize the methanol amount and it has been revealed that the best performance was achieved by using methanol/wet biomass ratio of 8:1. The effect of using various co-solvents in increasing the efficiency of the supercritical process was investigated. It has been shown that hexane was the most effective co-solvent and its optimal ratio respect to wet biomass was 6:1. The... 

    Nanomedicine applications in orthopedic medicine: State of the art

    , Article International Journal of Nanomedicine ; Volume 10 , 2015 , Pages 6039-6054 ; 11769114 (ISSN) Mazaheri, M ; Eslahi, N ; Ordikhani, F ; Tamjid, E ; Simchi, A ; Sharif University of Technology
    Dove Medical Press Ltd  2015
    The technological and clinical need for orthopedic replacement materials has led to significant advances in the field of nanomedicine, which embraces the breadth of nanotechnology from pharmacological agents and surface modification through to regulation and toxicology. A variety of nanostructures with unique chemical, physical, and biological properties have been engineered to improve the functionality and reliability of implantable medical devices. However, mimicking living bone tissue is still a challenge. The scope of this review is to highlight the most recent accomplishments and trends in designing nanomaterials and their applications in orthopedics with an outline on future directions... 

    Enhancement of fungal delignification of rice straw by Trichoderma viride sp. to improve its saccharification

    , Article Biochemical Engineering Journal ; Volume 101 , September , 2015 , Pages 77-84 ; 1369703X (ISSN) Ghorbani, F ; Karimi, M ; Biria, D ; Kariminia, H. R ; Jeihanipour, A ; Sharif University of Technology
    Elsevier  2015
    Fungal delignification can be considered as a feasible process to pre-treat lignocellulosic biomass in biofuel production, if its performance is improved in terms of efficiency thorough a few modifications. In this study, Trichoderma viride was utilized to investigate the effect of wet-milling, addition of surfactant (Tween 80) and optimization of operating factors such as temperature, biomass to liquid medium ratio and glucose concentration on biodelignification of rice straw. Next, the enzymatic hydrolysis of pretreated biomass was studied at various pretreatment times. Results revealed that the wet milling and addition of surfactant increases the lignin removal about 15% and 11%,... 

    Antibacterial silver nanoparticles in polyvinyl alcohol/sodium alginate blend produced by gamma irradiation

    , Article International Journal of Biological Macromolecules ; Volume 80 , 2015 , Pages 170-176 ; 01418130 (ISSN) Eghbalifam, N ; Frounchi, M ; Dadbin, S ; Sharif University of Technology
    Polyvinyl alcohol/sodium alginate/nano silver (PVA/SA/Ag) composite films were made by solution casting method. Gamma irradiation was used to synthesize silver nanoparticles in situ via reduction of silver nitrate without using harmful chemical agents for biomedical applications. UV-vis and XRD results demonstrated that spherical silver nanoparticles were produced even at low irradiation dose of 5. kGy. By increasing irradiation dose, more nanoparticles were synthesized while no PVA hydrogel was formed up to 15. kGy. Also the size of nanoparticles was reduced with increasing gamma dose evidenced by higher release rate of silver nanoparticles in lukewarm water and SEM images. Comparing SEM... 

    Effect of various carbon sources on biomass and lipid production of Chlorella vulgaris during nutrient sufficient and nitrogen starvation conditions

    , Article Bioresource Technology ; Volume 180 , 2015 , Pages 311-317 ; 09608524 (ISSN) Abedini Najafabadi, H ; Malekzadeh, M ; Jalilian, F ; Vossoughi, M ; Pazuki, G ; Sharif University of Technology
    In this research, a two-stage process consisting of cultivation in nutrient rich and nitrogen starvation conditions was employed to enhance lipid production in Chlorella vulgaris algal biomass. The effect of supplying different organic and inorganic carbon sources on cultivation behavior was investigated. During nutrient sufficient condition (stage I), the highest biomass productivity of 0.158. ±. 0.011. g/L/d was achieved by using sodium bicarbonate followed by 0.130. ±. 0.013, 0.111. ±. 0.005 and 0.098. ±. 0.003. g/L/d for sodium acetate, carbon dioxide and molasses, respectively. Cultivation under nitrogen starvation process (stage II) indicated that the lipid and fatty acid content... 

    Directional migration and differentiation of neural stem cells within three-dimensional microenvironments

    , Article Integrative Biology (United Kingdom) ; Volume 7, Issue 3 , Jan , 2015 , Pages 335-344 ; 17579694 (ISSN) Shamloo, A ; Heibatollahi, M ; Mofrad, M. R. K ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Harnessing neural stem cells to repair neuronal damage is a promising potential treatment for neuronal diseases. To enable future therapeutic efficacy, the survival, proliferation, migration and differentiation of neural stem/progenitor cells (NPCs) should be accurately studied and optimized in in vitro platforms before transplanting these cells into the body for treatment purposes. Such studies can determine the appropriate quantities of the biochemical and biomechanical factors needed to control and optimize NPC behavior in vivo. In this study, NPCs were cultured within a microfluidic device while being encapsulated within the collagen matrix. The migration and differentiation of NPCs were... 

    Resiliency of cortical neural networks against cascaded failures

    , Article NeuroReport ; Volume 26, Issue 12 , 2015 , Pages 718-722 ; 09594965 (ISSN) Jalili, M ; Sharif University of Technology
    Lippincott Williams and Wilkins  2015
    Network tools have been extensively applied to study the properties of brain functional and anatomical networks. In this paper, resiliency of Caenorhabditis elegans cortical networks against cascaded failures is studied. To this end, directed network formed by chemical connections and undirected network formed by electrical couplings through gap junctions are considered. Furthermore, two types of C. elegans networks are studied: the whole cortical network of the hermaphrodite type and the network of the posterior cortex in male C. elegans. The results show that resiliency of hermaphrodite and male networks is different. The male cortical network of chemical synapses shows extensively weaker... 

    Optimization of operating parameters for efficient photocatalytic inactivation of Escherichia coli based on a statistical design of experiments

    , Article Water Science and Technology ; Volume 71, Issue 6 , 2015 , Pages 823-831 ; 02731223 (ISSN) Feilizadeh, M ; Alemzadeh, I ; Delparish, A ; Karimi Estahbanati, M. R ; Soleimani, M ; Jangjou, Y ; Vosoughi, A ; Sharif University of Technology
    IWA Publishing  2015
    In this work, the individual and interaction effects of three key operating parameters of the photocatalytic disinfection process were evaluated and optimized using response surface methodology (RSM) for the first time. The chosen operating parameters were: reaction temperature, initial pH of the reaction mixture and TiO2 P-25 photocatalyst loading. Escherichia coli concentration, after 90 minutes irradiation of UV-A light, was selected as the response. Twenty sets of photocatalytic disinfection experiments were conducted by adjusting operating parameters at five levels using the central composite design. Based on the experimental data, a semi-empirical expression was established and applied...