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Total 52 records

    Solving MEC model of haplotype reconstruction using information fusion, single greedy and parallel clustering approaches

    , Article 6th IEEE/ACS International Conference on Computer Systems and Applications, AICCSA 2008, Doha, 31 March 2008 through 4 April 2008 ; 2008 , Pages 15-19 ; 9781424419685 (ISBN) Asgarian, E ; Moeinzadeh, M. H ; Sharifian-R, S ; Najafi-A, A ; Ramezani, A ; Habibi, J ; Mohammadzadeh, J ; Sharif University of Technology
    2008
    Abstract
    Haplotype information has become increasingly important in analyzing fine-scale molecular genetics data, Due to the mutated form in human genome; SNPs (Single Nucleotide Polymorphism) are responsible for some genetic diseases. As a consequence, obtaining all SNPs from human populations is one of the primary goals of studies in human genomics. In this paper, a data fusion method based on multiple parallel classifiers for reconstruction of haplotypes from a given sample Single Nucleotide Polymorphism (SNP) is proposed. First, we design a single greedy algorithm for solving haplotype reconstructions. [2] is used as an efficient approach to be combined with first classification method. The... 

    The performances of the chi-square test and complexity measures for signal recognition in biological sequences

    , Article Journal of Theoretical Biology ; Volume 251, Issue 2 , 2008 , Pages 380-387 ; 00225193 (ISSN) Pirhaji, L ; Kargar, M ; Sheari, A ; Poormohammadi, H ; Sadeghi, M ; Pezeshk, H ; Eslahchi, C ; Sharif University of Technology
    2008
    Abstract
    With large amounts of experimental data, modern molecular biology needs appropriate methods to deal with biological sequences. In this work, we apply a statistical method (Pearson's chi-square test) to recognize the signals appear in the whole genome of the Escherichia coli. To show the effectiveness of the method, we compare the Pearson's chi-square test with linguistic complexity on the complete genome of E. coli. The results suggest that Pearson's chi-square test is an efficient method for distinguishing genes (coding regions) form pseudogenes (noncoding regions). On the other hand, the performance of the linguistic complexity is much lower than the chi-square test method. We also use the... 

    Inferring Signaling Pathways from RNAi Data Using Machine Learning

    , M.Sc. Thesis Sharif University of Technology Mazloomian, Alborz (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    One of the standing problems in Molecular Biology and Bioinformatics is uncovering signaling pathways. Discovering the causes of many cancer-like diseases and developing better treatments for them, requires a better understanding of the behavior of cellular processes. Understanding signaling pathways can help to realize cellular processes. Due to the fast increase of possible signaling pathways when the number of components increases, the problem seems to have an inherent complexity. One of the recent methods for generating data relating to such networks is RNA interference technique. In this thesis we use data which are provided by this method. We propose two methods to infer signaling... 

    History matching of naturally fractured reservoirs based on the recovery curve method

    , Article Journal of Petroleum Science and Engineering ; Vol. 126, issue , February , 2015 , p. 211-221 ; ISSN: 09204105 Ghaedi, M ; Masihi, M ; Heinemann, Z. E ; Ghazanfari, M. H ; Sharif University of Technology
    Abstract
    The discrete fracture network (DFN) and Multiple-Continua concept are among the most widely used methods to model naturally fractured reservoirs. Each faces specific limitations. The recently introduced recovery curve method (RCM) is believed to be a compromise between these two current methods. In this method the recovery curves are used to determine the amount of mass exchanges between the matrix and fracture mediums. Two recovery curves are assigned for each simulation cell, one curve for gas displacement in the presence of the gravity drainage mechanism, and another for water displacement in the case of the occurrence of the imbibition mechanism. These curves describe matrix-fracture... 

    Substrate oscillations boost recombinant protein release from Escherichia coli

    , Article Bioprocess and Biosystems Engineering ; Volume 37, Issue 5 , May , 2014 , Pages 881-890 ; ISSN: 16157591 Jazini, M ; Herwig, C ; Sharif University of Technology
    Abstract
    Intracellular production of recombinant proteins in prokaryotes necessitates subsequent disruption of cells for protein recovery. Since the cell disruption and subsequent purification steps largely contribute to the total production cost, scalable tools for protein release into the extracellular space is of utmost importance. Although there are several ways for enhancing protein release, changing culture conditions is rather a simple and scalable approach compared to, for example, molecular cell design. This contribution aimed at quantitatively studying process technological means to boost protein release of a periplasmatic recombinant protein (alkaline phosphatase) from E. coli.... 

    Comparison of deformation analysis of a biological cell under an injection force using analytical, experimental and finite element methods and Artificial Neural Network

    , Article ASME 2011 International Mechanical Engineering Congress and Exposition, IMECE 2011 ; Volume 2 , 2011 , Pages 499-507 ; 9780791854884 (ISBN) Sarvi, M. N ; Ahmadian, M. T ; ASME ; Sharif University of Technology
    Abstract
    Biological cell injection is a sensitive and important work which is implemented in injection of foreign materials into individual cells. Microinjection is significantly developed in the field of drug discovery and genetics so predicting the behavior of cell in microinjection is remarkably important because a tiny excessive manipulation force can destroy the tissue of the biological cell. There are a few analytical methods available to simulate the cell injection, hence the numerical methods such as FEM are suitable to be used to model the microinjection. In this study, a new spherical super element is presented to model the biological cells and deformation of a specific cell under an... 

    History matching of naturally fractured reservoirs based on the recovery curve method

    , Article Journal of Petroleum Science and Engineering ; Volume 126 , 2015 , Pages 211-221 ; 09204105 (ISSN) Ghaedi, M ; Masihi, M ; Heinemann, Z. E ; Ghazanfari, M. H ; Sharif University of Technology
    Abstract
    The discrete fracture network (DFN) and Multiple-Continua concept are among the most widely used methods to model naturally fractured reservoirs. Each faces specific limitations. The recently introduced recovery curve method (RCM) is believed to be a compromise between these two current methods. In this method the recovery curves are used to determine the amount of mass exchanges between the matrix and fracture mediums. Two recovery curves are assigned for each simulation cell, one curve for gas displacement in the presence of the gravity drainage mechanism, and another for water displacement in the case of the occurrence of the imbibition mechanism. These curves describe matrix-fracture... 

    Toward chemical perfection of graphene-based gene carrier via ugi multicomponent assembly process

    , Article Biomacromolecules ; Volume 17, Issue 9 , 2016 , Pages 2963-2971 ; 15257797 (ISSN) Rezaei, A ; Akhavan, O ; Hashemi, E ; Shamsara, M ; Sharif University of Technology
    American Chemical Society 
    Abstract
    The graphene-based materials with unique, versatile, and tunable properties have brought new opportunities for the leading edge of advanced nanobiotechnology. In this regard, the use of graphene in gene delivery applications is still at early stages. In this study, we successfully designed a new complex of carboxylated-graphene (G-COOH) with ethidium bromide (EtBr) and used it as a nanovector for efficient gene delivery into the AGS cells. G-COOH, with carboxyl functions on its surface, in the presence of EtBr, formaldehyde, and cyclohexylisocyanide were participated in Ugi four component reaction to fabricate a stable amphiphilic graphene-EtBr (AG-EtBr) composite. The coupling reaction was... 

    Simulation of softening kinetics and microstructural events in aluminum alloy subjected to single and multi-pass rolling operations

    , Article Applied Mathematical Modelling ; Volume 40, Issue 17-18 , 2016 , Pages 7571-7582 ; 0307904X (ISSN) Shabaniverki, S ; Serajzadeh, S ; Sharif University of Technology
    Elsevier Inc 
    Abstract
    In this study, a multi-scale model is proposed to assess softening kinetics and microstructural changes during isothermal annealing within an aluminum alloy. In the first stage, an elastic-plastic finite element analysis is performed for computing the distributions of effective plastic strain and stress while the stored energy after cold rolling is defined based on the predicted data and then utilized for generation of the initial conditions in the microstructural analysis. In the next stage, an algorithm based on cellular automata coupled with a first order rate equation is used to determine the progress of softening behavior at elevated temperatures while both recrystallization and... 

    Development of a novel nano-sized anti-VEGFA nanobody with enhanced physicochemical and pharmacokinetic properties

    , Article Artificial Cells, Nanomedicine and Biotechnology ; 2017 , Pages 1-13 ; 21691401 (ISSN) Khodabakhsh, F ; Norouzian, D ; Vaziri, B ; Ahangari Cohan, R ; Sardari, S ; Mahboudi, F ; Behdani, M ; Mansouri, K ; Mehdizadeh, A ; Sharif University of Technology
    Abstract
    Since physiological and pathological processes occur at nano-environments, nanotechnology has considered as an efficient tool for designing of next generation specific biomolecules with enhanced pharmacodynamic and pharmacodynamic properties. In the current investigation, by control of the size and hydrodynamic volume at the nanoscale, for the first time, physicochemical and pharmacokinetic properties of an anti-VEGFA nanobody was remarkably improved by attachment of a Proline-Alanine-Serine (PAS) rich sequence. The results elucidated unexpected impressive effects of PAS sequence on physicochemical properties especially on size, hydrodynamics radius, and even solubility of nanobody. CD... 

    Development of a novel nano-sized anti-VEGFA nanobody with enhanced physicochemical and pharmacokinetic properties

    , Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 46, Issue 7 , 2018 , Pages 1402-1414 ; 21691401 (ISSN) Khodabakhsh, F ; Norouzian, D ; Vaziri, B ; Ahangari Cohan, R ; Sardari, S ; Mahboudi, F ; Behdani, M ; Mansouri, K ; Mehdizadeh, A ; Sharif University of Technology
    Abstract
    Since physiological and pathological processes occur at nano-environments, nanotechnology has considered as an efficient tool for designing of next generation specific biomolecules with enhanced pharmacodynamic and pharmacodynamic properties. In the current investigation, by control of the size and hydrodynamic volume at the nanoscale, for the first time, physicochemical and pharmacokinetic properties of an anti-VEGFA nanobody was remarkably improved by attachment of a Proline-Alanine-Serine (PAS) rich sequence. The results elucidated unexpected impressive effects of PAS sequence on physicochemical properties especially on size, hydrodynamics radius, and even solubility of nanobody. CD... 

    A clustering-based algorithm for de novo motif discovery in DNA sequences

    , Article 2017 24th Iranian Conference on Biomedical Engineering and 2017 2nd International Iranian Conference on Biomedical Engineering, ICBME 2017, 30 November 2017 through 1 December 2017 ; 2018 ; 9781538636091 (ISBN) Ebrahim Abadi, M. H ; Fatemizadeh, E ; Sharif University of Technology
    Abstract
    Motif discovery is a challenging problem in molecular biology and has been attracting researcher's attention for years. Different kind of data and computational methods have been used to unravel this problem, but there is still room for improvement. In this study, our goal was to develop a method with the ability to identify all the TFBS signals, including known and unknown, inside the input set of sequences. We developed a clustering method specialized as part of our algorithm which outperforms other existing clustering methods such as DNACLUST and CD-HIT-EST in clustering short sequences. A scoring system was needed to determine how much a cluster is close to being a real motif. Multiple...