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    Evaluation of the ankylosing spondylitis transcriptome for oxidative phosphorylation pathway: the shared pathway with neurodegenerative diseases

    , Article Iranian journal of allergy, asthma, and immunology ; Volume 20, Issue 5 , 2021 , Pages 563-573 ; 17355249 (ISSN) Lari, A ; Gholami Pourbadie, H ; Sharifi Zarchi, A ; Aslani, S ; Nejatbakhsh Samimi, L ; Jamshidi, A ; Mahmoudi, M ; Sharif University of Technology
    NLM (Medline)  2021
    Abstract
    Ankylosing spondylitis (AS) is a systemic inflammatory disorder of joints and entheses. Recent studies have reported an increased prevalence of dementia in AS patients. However, data for exploring the association between dementia and AS remain uncertain. In this study, enriched pathways and differentially expressed genes (DEGs) were identified in whole blood transcription data of AS patients obtained from the gene expression omnibus (GEO) database; using gene set enrichment analysis (GSEA) and differential expression analysis. Four pathways, including oxidative phosphorylation, Alzheimer's, Parkinson's, and Huntington's diseases were significantly enriched in AS patients compared to the... 

    Estimating aqueous nanofluids viscosity via GEP modeling: Correlation development and data assessment

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 41, Issue 1 , 2022 , Pages 266-283 ; 10219986 (ISSN) Mahdaviara, M ; Rostami, A ; Shahbazi, K ; Shokrollahi, A ; Ghazanfari, M. H ; Sharif University of Technology
    Iranian Institute of Research and Development in Chemical Industries  2022
    Abstract
    This paper focuses on developing a new method that represents user-accessible correlation for the estimation of water-based nanofluids viscosity. For this, an evolutionary algorithm, namely Gene Expression Programming (GEP), was adapted based on a wide selection of literature published databanks including 819 water-based nanofluids viscosity points. The developed model utilized the base fluid viscosity as well as volume fraction and size of the nanoparticles as the inputs of the model. Several statistical parameters integrated with graphical plots were employed in order to assess the accuracy of the proposed GEP-based model. Results of the evaluation demonstrate fairly enough accuracy of the... 

    Detection and Estimation of Key Parameters in Traffic Models Using Data Mining Tools

    , M.Sc. Thesis Sharif University of Technology Moadab, Amir Hossein (Author) ; Khedmati, Majid (Supervisor)
    Abstract
    Nowadays, investigating the factors affecting traffic models from different aspects such as metropolitan planning according to the present conditions can help high-level decision-makers and also, at the micro-level, help the travelers to make appropriate decisions for scheduling affairs, route selection, and vehicle type selection. Given the importance of this topic, a framework will be presented in this study that will evaluate the impact of some identified factors such as travel distance, climate, and urban events, and then all these factors will be presented in mathematical formulas. In the end, based on the model, the travel time will be predicted. In this framework, gene expression... 

    CytoGTA: a cytoscape plugin for identifying discriminative subnetwork markers using a game theoretic approach

    , Article PLoS ONE ; Volume 12, Issue 10 , 2017 ; 19326203 (ISSN) Farahmand, S ; Foroughmand Araabi, M. H ; Goliaei, S ; Razaghi Moghadam, Z ; Sharif University of Technology
    Abstract
    In recent years, analyzing genome-wide expression profiles to find genetic markers has received much attention as a challenging field of research aiming at unveiling biological mechanisms behind complex disorders. The identification of reliable and reproducible markers has lately been achieved by integrating genome-scale functional relationships and transcriptome datasets, and a number of algorithms have been developed to support this strategy. In this paper, we present a promising and easily applicable tool to accomplish this goal, namely CytoGTA, which is a Cytoscape plug-in that relies on an optimistic game theoretic approach (GTA) for identifying subnetwork markers. Given transcriptomic... 

    Exploration of Existing Patterns in Copy Number Variations of Genetic Diseases and Disorders

    , Ph.D. Dissertation Sharif University of Technology Rahaie, Zahra (Author) ; Rabiee, Hamid Reza (Supervisor)
    Abstract
    One of the main sources of genetic variations are structural variations, including the widespread Copy Number Variations (CNVs). CNVs include two types, copy of genetic material (duplication) and loss of part of genetic sequence (deletion) and typically range from one kilobase pairs (Kbp) to several megabase pairs (Mbp) in size. Most of the copy number variations are occured in in healthy people; however, these variants can also contribute to numerous diseases through several genetic mechanisms (e.g. change gene dosage through insertions, duplications or deletions). The CNV study can provide greater insight into the etiology of disease phenotypes. Nowadays, with the huge amount of investment... 

    Inference of gene regulatory networks by extended Kalman filtering using gene expression time seriesdata

    , Article BIOINFORMATICS 2012 - Proceedings of the International Conference on Bioinformatics Models, Methods and Algorithms ; 2012 , Pages 150-155 ; 9789898425904 (ISBN) Fouladi, R ; Fatemizadeh, E ; Arab, S. S ; Sharif University of Technology
    2012
    Abstract
    In this paper, the Extended Kalman filtering (EKF) approach has been used to infer gene regulatory networks using time-series gene expression data. Gene expression values are considered stochastic processes and the gene regulatory network, a dynamical nonlinear stochastic model. Using these values and a modified Kalman filtering approach, the model's parameters and consequently the interactions amongst genes are predicted. In this paper, each gene-gene interaction is modeled using a linear term, a nonlinear one, and a constant term. The linear and nonlinear term coefficients are included in the state vector together with the gene expressions' true values. Through the extended Kalman... 

    Development and in vitro evaluation of photocurable GelMA/PEGDA hybrid hydrogel for corneal stromal cells delivery

    , Article Materials Today Communications ; Volume 27 , 2021 ; 23524928 (ISSN) Mahdavi, S. S ; Abdekhodaie, M. J ; Mashayekhan, S ; Baradaran Rafii, A ; Kim, K ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Gelatin methacrylate (GelMA) was proved to be a promising bioink for corneal stromal cell delivery. However, GelMA has low mechanical properties which makes it difficult to be suturable and handled for clinical applicattion. In this study, three different ratios of 12.5 % GelMA and 10 % PEGDA were investigated for corneal stromal cells delivery. The mixture containing 75 % GelMA and 25 % PEGDA (75G25P) was found to have reasonable cell viability and suturing strength. Moreover, collagen nanofibers were incorporated into 75G25P hydrogel to improve the mechanical and biomimetic properties of the construct (75G25P-E). A hybrid structure was obtained by injecting the optimized bioink on the... 

    Utilization of gene expression programming for modeling of mechanical performance of titanium/carbonated hydroxyapatite nanobiocomposites: The combination of artificial intelligence and material science

    , Article International Journal of Engineering, Transactions A: Basics ; Volume 34, Issue 4 , 2021 , Pages 948-955 ; 17281431 (ISSN) Shojaei, M. R ; Khayati, G. R ; Hasani, A ; Sharif University of Technology
    Materials and Energy Research Center  2021
    Abstract
    Titanium carbonated hydroxyapatite (Ti/CHA) nanobiocomposites have extensive biological applications due to the excellent biocompatibility and similar characteristics to the human bone. Ti/CHA nanobiocomposite has good biological properties but it suffer from diverse characteristics especially in hardness, Young's modulus, apparent porosity and relative density. This investigation is an attempt to propose the predictive models using gene expression programming (GEP) to estimate these characteristics. In this regards, GEP is used to model and compare the effect of practical variables including pressure, Ti/CHA contents and sintering temperature on their monitored properties. To achieve this... 

    Using Transductive Learning Classification in Bioinformatics

    , M.Sc. Thesis Sharif University of Technology Tajari, Hossein (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    Classification is one of the most important problems in machine learning area. Reliable and successful classification is essential for diagnosing patients for further treatment. In many applications such as bioinformatics unlabeled data is abundant and available. However labeling data is much more difficult and expensive to obtain. This dissertation presents a novel transductive approach for the development of robust microarray data classification. The transduction problem is to estimate the value of classification function at the given points in the working set. This contrasts with the standard inductive learning problem of estimating the classification method at all possible values and... 

    Identification of the Set of Single Nucleotide Variants in Genome Responsible for the Differentiation of Expression of Genes

    , M.Sc. Thesis Sharif University of Technology Khatami, Mahshid (Author) ; Rabiee, Hamid Reza (Supervisor) ; Beigi, Hamid (Supervisor)
    Abstract
    Single nucleotide polymorphs, There are changes caused by a mutation in a nucleotide in the Dena sequence. Mononucleotide polymorphisms are the most common type of genetic variation. Some of these changes have little or no effect on cells, while others cause significant changes in the expression of cell genes that can lead to disease or resistance to certain diseases. Because of the importance of these changes and their effect on cell function, the relationships between these changes are also important. Over the past decade, thousands of single disease-related mononucleotide polymorphisms have been identified in genome-related studies. Studies in this field have shown that the expression of... 

    Using the group method for the synthesis of copper/ZrO2 nanocomposites to achieve high wear resistance by ball milling and spark plasma sintering

    , Article Ceramics International ; Volume 48, Issue 12 , 2022 , Pages 17576-17588 ; 02728842 (ISSN) Shojaei, M ; Hasani, A ; Amiri, Z ; Khayati, G. R ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    The use of ZrO2 nanoparticles is common in the Cu matrix to manufacture Cu/ZrO2 nanocomposites. Many approaches and parameters produce Cu/ZrO2 nanocomposites with an appropriate wear rate and other properties. Hence, proposing an accurate and reliable model was imperative. The main goal of this paper is to find out the best models among the ant colony optimization (ACO), gene expression programming (GEP), artificial bee colony (ABC), and gray wolf optimization algorithm (GWOA) to predict the wear rate of/ZrO2 nanocomposites. To the best of our knowledge, this is the first research that predicts Cu/ZrO2 nanocomposites wear rate using group modeling. To develop models, 105 data were collected... 

    Fuzzy support vector machine: An efficient rule-based classification technique for microarrays

    , Article BMC Bioinformatics ; Volume 14, Issue SUPPL13 , 2013 ; 14712105 (ISSN) Hajiloo, M ; Rabiee, H. R ; Anooshahpour, M ; Sharif University of Technology
    2013
    Abstract
    Background: The abundance of gene expression microarray data has led to the development of machine learning algorithms applicable for tackling disease diagnosis, disease prognosis, and treatment selection problems. However, these algorithms often produce classifiers with weaknesses in terms of accuracy, robustness, and interpretability. This paper introduces fuzzy support vector machine which is a learning algorithm based on combination of fuzzy classifiers and kernel machines for microarray classification.Results: Experimental results on public leukemia, prostate, and colon cancer datasets show that fuzzy support vector machine applied in combination with filter or wrapper feature selection... 

    Analysis of Gene Expression Data in Bioinformatics Data Sets Using Machine Learning Approaches

    , M.Sc. Thesis Sharif University of Technology Bagherian, Misagh (Author) ; Beigy, Hamid (Supervisor)
    Abstract
    As a robust and accurate classification of tumors is necessary for successful treatment of cancer, classification of DNA microarray data has been widely used in successful diagnosis of cancers and some other biological diseases. But the main challenge in classification of microarray data is the extreme asymmetry between the dimensionality of features (usually thousands or even tens of thousands of genes) and that of tissues (few hundreds of samples). Because of such curse of dimensionality, a class prediction model could be very successful in classifying one type of dataset but may fail to perform well in some other ones. Overfitting is another problem that prevents conventional learning... 

    A Semi-Supervised Algorithms for Clustering Microarray Data

    , M.Sc. Thesis Sharif University of Technology Eslamzadeh, Habibollah (Author) ; Mahdavi Amiri, Nezamoddin (Supervisor) ; Madadkar Sobhani, Armin (Supervisor)
    Abstract
    Microarray which is also known as Biochip is a flat substrate of glass with the size of 1 ×1 cm on which a numerous number of biosensors are placed in an array format. Microarray DNAs are used to measure expression level of thousands of genes. Repeating these experiments in different conditions can result in patterns of expression. After preparation, the florescent sample is hybridized with the sensors of microarray surface and fluoresce intensities of the spots are measured by a special camera called CCD. The obtained pictures are examined by a computer and the spot lights converted into numerical data by image processing algorithms. Putting these numbers into matrices of size m×n is... 

    Bayesian Filtering Approach to Improve Gene Regulatory Networks Inference Using Gene Expression Time Series

    , M.Sc. Thesis Sharif University of Technology Fouladi, Ramouna (Author) ; Fatemizadeh, Emadoddin (Supervisor) ; Arab, Shahriar (Co-Advisor)
    Abstract
    Gene regulatory modeling in different species is one of the main aims of Bioinformatics. Regarding the limitations of the data available and the perspectives which should be taken into account for modeling such networks, proposed methods up to now have not yet been successful in yielding a comprehensive model. In one of the recent researches, the Gene regulation process is considered as a nonlinear dynamic stochastic process and described by state space equations. Afterwards, in order for the unknown parameters to be estimated, Extended Kalman Filtering is used. In this thesis, first of all, Gene complexes are taken into consideration instead of genes and afterwards, Extended Kalman... 

    Distributed Processing of Next Generation Sequencing Data Set

    , M.Sc. Thesis Sharif University of Technology Hadadian Nejad Yousefi, Mostafa (Author) ; Goudarzi, Maziar (Supervisor) ; Motahari, Abolfazl (Supervisor)
    Abstract
    DNA analysis plays a significant role in fields such as pharmacy, agriculture, genealogy, and forensics. Next generation sequencing datasets cover a gene several times due to a large number of readings. Therefore, the initial data volume is several times the amount of memory required to store the DNA strand. First, the DNA sequence of a sample should be made using the primary data, and then the difference should be found by comparing the sample DNA sequence with the reference DNA sequence. By finding these differences, one can extract the characteristics of the tested species. The extracted properties are precious for genetics researchers. For example, they can produce drugs that are... 

    Identifying Core Genes in Estimation of Missing Gene Expressions

    , M.Sc. Thesis Sharif University of Technology Darvish Shafighi, Shadi (Author) ; Motahari, Abolfazl (Supervisor)
    Abstract
    Characterizing cellular states in response to various disease conditions is an important issue which is addressed by different methods such as Large-scale gene expression profiling. One of the most important challenges in front of bioinformaticians is the loss of data because expression profiling is still very expensive. It is understood that profiling a group of selected genes could be enough for understanding all of the gene expression profile.In this research, we propose a fast method for estimation of the missing values inlow-rank matrices. We consider the highly correlated expression profiles as a low-rank matrix. Then, we used this new method in a proposed algorithm which will select... 

    Analysis of Genes Regulating Beta Cells Cell Cycle

    , M.Sc. Thesis Sharif University of Technology Saraei, Tannaz (Author) ; Motahari, Abolfazl (Supervisor)
    Abstract
    Diabetes mellitus is a group of disorders where the level of blood sugar remains high for a long period of time. This increase may be due to either reduced insulin secretion from the pancreatic gland, or insulin resistance, or both. Another key reason is the destruction of beta cells due to functional defect in the body’s immune system. Current treatments include controlling diet, insulin injection and pancreatic transplantation, all of which are temporary. For this reason, finding genetic factors participating in the progression of the disease and adapting treatments to these factors are under intensive studies.In this thesis, available information resources including genomic, biological... 

    Identification of Driver Genes in Glioblastoma Based on Single-Cell Gene Expression Data Utilizing the Concept of Pseudotime and Phylogenetic Analysis

    , M.Sc. Thesis Sharif University of Technology Mirza Abolhassani, Fatemeh (Author) ; Foroughmand Aarabi, Mohammad Hadi (Supervisor) ; Kavousi, Kaveh (Co-Supervisor) ; Zare Mirakabad, Fatemeh (Co-Supervisor)
    Abstract
    Genetic heterogeneity within a tumor, which occurs during cancer evolution, is one of the reasons for treatment failure and increased chances of drug resistance. Cancer cells initially derive from a mutated progenitor cell, resulting in shared mutated genes. Throughout the course of tumor formation and progression, the occurrence of new mutations is possible, leading to the generation of cancer cells with various mutated genes. An appropriate approach is to identify the sequence of mutations that have occurred in the tumor, which can be inferred from single-cell sequencing data. Singlecell data provides valuable information about branching events in the evolution of a cancerous tumor. In... 

    Deep feature extraction of single-cell transcriptomes by generative adversarial network

    , Article Bioinformatics ; Volume 37, Issue 10 , 2021 , Pages 1345-1351 ; 13674803 (ISSN) Bahrami, M ; Maitra, M ; Nagy, C ; Turecki, G ; Rabiee, H. R ; Li, Y ; Sharif University of Technology
    Oxford University Press  2021
    Abstract
    Motivation: Single-cell RNA-sequencing (scRNA-seq) offers the opportunity to dissect heterogeneous cellular compositions and interrogate the cell-type-specific gene expression patterns across diverse conditions. However, batch effects such as laboratory conditions and individual-variability hinder their usage in cross-condition designs. Results: Here, we present a single-cell Generative Adversarial Network (scGAN) to simultaneously acquire patterns from raw data while minimizing the confounding effect driven by technical artifacts or other factors inherent to the data. Specifically, scGAN models the data likelihood of the raw scRNA-seq counts by projecting each cell onto a latent embedding....