Loading...
Search for:
diseases
0.018 seconds
Total 541 records
Scaffold Design and Fabrication for Retinal Tissue Engineering
, M.Sc. Thesis Sharif University of Technology ; Mashayekhan, Shohreh (Supervisor)
Abstract
The retina, a photosensitive area in the central nervous system, is delicate and intricate. It is susceptible to degenerative disorders such as age-related macular degeneration (AMD), retinitis pigmentosa (RP), Stargardt disease (SD), and glaucoma. These diseases can lead to severe vision loss and ultimately irreversible blindness by causing destruction or dysfunction of different types of retinal cells. Unfortunately, there are no proven treatment strategies to cure or reverse these degenerative disorders. However, cell transplantation therapies may be an alternative to replace distorted cells and improve an individual's vision. Recent clinical outcomes show that transplanted cells in the...
Design and Efficient Implementation of ECG-based Detection Algorithm for Dangerous Myocardial Problems
, M.Sc. Thesis Sharif University of Technology ; Hashemi, Matin (Supervisor) ; Vosooghi Vahdat, Bizhan (Co-Advisor)
Abstract
Cardiovascular diseases are the first leading cause of death in the world also in IRAN. Early detection of such problems can decrease the costs also can help to cure the patient but it needs continuous monitoring and automated classification of hearbeats. Mobile devices and wearable gadgets are good solutions which can help patients before visiting the doctor.In this research, an algorithm is introduced which with the help of ECG signal detects dangerous myocardial problems. Our approach is using deep learning method which were not considered much before. In the proposed algorithm ECG signal is processed in order to get features and with dimensionality reduction, input of the network gets...
Design and Efficient Implementation of Deep Learning Algorithm for ECG Classification
, M.Sc. Thesis Sharif University of Technology ; Hashemi, Matin (Supervisor)
Abstract
Cardiovascular diseases are the leading cause of death globally so early diagnosis of them is important. Many researchers focused on this field. First signs of cardiac diseases appear in the electrocardiogram signal. This signal represents the electrical activity of the heart so it’s primarily used for the detection and classification of cardiac arrhythmias. Permanent monitoring of this signal is not possible for specialists so we should do this by means of Artificial Intelligence. In this thesis, we use recurrent neural networks to classify electrocardiogram’s arrhythmias. This deep learning method, use two sources of data to learn from. The first part of data is global for everyone and the...
Improving the Performance of an Activity Recognition System Using Meaningful Data Augmentation and Deep Learning Methods
, M.Sc. Thesis Sharif University of Technology ; Behzadipour, Saeed (Supervisor)
Abstract
Researchers working at Mowafaghian Rehabilitation Research Center have decided to develop a telerehabilitation system named SEPANTA, especially designed for activity recognition of Parkinson's Disease patients. In this regard, the system uses 34 mobility exercises, including 20 LSVT-BIG activities (especially designed for PD patients) and 14 functional daily activities. Human Activity Recognition (HAR) systems faces various challenges e.g., intra-class variabilities, meaning differences in an activity performance by different persons or a person. Data augmentation and utilizing deep learning models are the most common solutions for the risen challenges. However, deep structures require an...
Diagnosis of COVID-19 Using Deep Learning Techniques
, M.Sc. Thesis Sharif University of Technology ; Hemmatyar, Ali Mohammad Afshin (Supervisor)
Abstract
In the last few years, the most important problem to find a solution for the COVID-19 disease, and tests show that many factors are effective in the health and recovery of people with this disease. Therefore, scientists all over the world are looking to prevent the spread of this disease by identifying the effective factors in the recovery of corona patients and finding solutions for their health. The proposed algorithm is hybrid deep learning model CNN+GRU and appeal them to the laboratory test data from hospital. In this research, the goal is to be able to diagnose this disease in time with routine laboratory test, which consist of three main stages. In the first stage: initial...
A Data-Driven Optimization Methodology to Improve Unmatched Pairs Assignment in Kidney Exchange Problem
, M.Sc. Thesis Sharif University of Technology ; Najafi, Mahdi (Supervisor) ; Rafiee, Majid (Supervisor)
Abstract
One of the most common and effective ways to treat end-stage renal disease is the use of kidney exchange techniques. However, the main problem with this treatment is the presence of many barriers to allocating kidney pairs to each other, which reduces the success of kidney transplants. Among different types of kidney transplantation methods, the present study utilizes kidney transplantation cycles to develop the allocation of unmatched pairs in kidney transplantation using a data-driven optimization technique. In this study, HLA patients were considered as simulated and also a two-objective model in the kidney exchange network was designed to maximize the probability of kidney...
A Mathematical Model to Organize Transplants in a Kidney Exchange Program with Uncertain Failures
, M.Sc. Thesis Sharif University of Technology ; Najafi, Mehdi (Supervisor) ; Shadrokh, Shahram (Supervisor)
Abstract
Kidney transplants are vital for patients with end-stage kidney disease. Therefore, it is essential to allocate kidneys to patients efficiently. Kidney Exchange Programs allow patients with incompatible donors to exchange donors and receive a suitable kidney. In practice, these exchanges occur within cyclic or chain-like structures. Planned transplants may be canceled before the transplant takes place, for a variety of reasons. Failure of one transplant in a cycle or chain can result in the failure of all transplants in that cycle or chain, which can lead to drastic inefficiency in the exchange program.In this thesis, we study kidney exchange programs under uncertainty. We consider...
A Comprehensive Approach for the Validation of Lumbar Spine Finite Element Models Investigating Post-Fusion Adjacent Segment Effects
, M.Sc. Thesis Sharif University of Technology ; Arjomand, Navid (Supervisor)
Abstract
Spinal fusion surgery is usually followed by accelerated degenerative changes in the unfused segments above and below the treated segment(s), i.e., adjacent segment disease (ASD). While a number of risk factors for ASD have been suggested, its exact pathogenesis remains to be identified. Finite element (FE) models are indispensable tools to investigate mechanical effects of fusion surgeries on post-fusion changes in the adjacent segment kinematics and kinetics. Existing modeling studies validate only their intact FE model against in vitro data and subsequently simulate post-fusion in vivo conditions. The present study provides a novel approach for the comprehensive validation of a lumbar...
Differences of the Brain’s Surprise Response Due to the Habituation Effect in Neurodegenerative Patients and Healthy People
, M.Sc. Thesis Sharif University of Technology ; Karbalaei Aghajan, Hamid (Supervisor)
Abstract
The brain is constantly placed in stochastic environments. This leads to the brain developing a probabilistic model for the environment. However, sometimes unexpected events occur that lead to surprise and a need for updating the probabilistic model. It can be concluded from this argument that reduction in brian’s surprise is a sign of learning. On the other hand, a probability distribution obtained from a probabilistic model contains an amount of uncertainty. Reducing this uncertainty can also be considered a sign of learning. Surprise and uncertainty can be obtained from a probability distribution using information theory concepts. Another important issue in learning is habituation, which...
Preparation of Hemodialysis Membrane on the Basis of Polysulfone
, M.Sc. Thesis Sharif University of Technology ; Moosavi, Ali (Supervisor) ; Abd Khodaei, Mohammad Jafar (Supervisor)
Abstract
In Hemodialysis, membrane dialyser and commonly hollow fibers are used to treat patients who suffer from end stage renal failure. When blood flows into membrane, it loses uremic toxins such as urea and creatinine. On the other hand, some of the vital proteins of blood pass through the membrane or they are adsorbed on the membrane surface. The more hydrophilicity of the membrane, the less adsorption of proteins is. In this study, to achieve high hydrophilicity and low adsorption of proteins on the polysulfone membrane surface, the presence of hydrophilic nano-particles SBA-15 in membrane composition is investigated. The nano-particles with mass percentages 0.25%, 0.5 % and 1 % to one mass of...
Simulation, Design and fabrication of Kidney on a Chip
, Ph.D. Dissertation Sharif University of Technology ; Saeedi, Mohammad Saeed (Supervisor) ; Firoozabadi, Bahar (Supervisor) ; Mosadegh, Bobak ($item.subfieldsMap.e)
Abstract
Renal diseases and consequently kidney failure is one of the important death factors around the world in recent years. It causes hundreds of thousands die every year and is in progress. Researchers believe that increasing chemical and nonchemical materials density in the blood which is the air pollution, use of tobacco and other parameters cause renal cells misfunction in urine filtration and regulation of blood pressure. The goal of this work is design and fabrication of a microfluidic device which provides different cell types to be cultured and imposed pressure. To do this, a high throughput microfluidic device is needed to mimic kidney biologically. Having such a device helps to analyze...
Evaluating the Effect of Innovation on Burden of Disease in Different Countries
, M.Sc. Thesis Sharif University of Technology ; Miremadi, Iman (Supervisor) ; Saleh Farazi, Mohammad (Co-Supervisor)
Abstract
In this comprehensive study, we explore the influence of general health innovation outputs on the burden of diseases across 70 nations spanning two decades, from 2000 to 2019, marking the first investigation of its kind. Our investigation takes into account associations among health-related patents, scholarly publications pertaining to health, and disability-adjusted life years (DALYs), a measure used to assess overall disease burden. Employing a robust fixed effect panel data model, our findings illuminate the notable impact health-related publications exert in mitigating disease burden universally across all countries examined. However, we did not find a similar association between patent...
Investigation of cervical spine curvature in females with postural neck pain
, Article Journal of Zanjan University of Medical Sciences and Health Services ; Volume 25, Issue 110 , 2017 , Pages 110-119 ; 16069366 (ISSN) ; Maroufi, N ; Ahmadi, A ; Behtash, H ; Hazhir Sahneh, S ; Parnianpour, M ; Sharif University of Technology
Zanjan University of Medical Sciences and Health Services
2017
Abstract
Background and Objective: Changes in the cervical spine curvature leads to increased shear force and compression stress on cervical spine and axial loading in different cervical segments. The objective of this study was to compare the general and segmental curvature in the upper and lower cervical spine of women with postural neck pain and Forward Head Posture (FHP), women without neck pain but with FHP and healthy women. Material and Methods: 45 women were divided into three groups: 15 women with postural neck pain and FHP, 15 women without neck pain but with FHP and 15 healthy women. Photography was used to assess neck posture while cervical spine curvature was measured using fluoroscopy...
Fsi simulation of a healthy coronary bifurcation for studying the mechanical stimuli of endothelial cells under different physiological conditions
, Article Journal of Mechanics in Medicine and Biology ; Volume 15, Issue 5 , October , 2015 ; 02195194 (ISSN) ; Saidi, M. S ; Firoozabadi, B ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2015
Abstract
Atherosclerosis is a world-spread and well-known disease. This disease strongly relates to the endothelial cells (ECs) function. Normally, the endothelial cells align in the flow direction in the atheroprotected sites; however, in the case of atheroprone sites these cells orient randomly. The mechanical stimuli such as wall shear stress and strains could determine the morphology and function of the endothelial cells. In the present study, we numerically simulated the left main coronary artery (LCA) and its branches to left anterior descending (LAD) and left circumflex coronary (LCX) artery using fluid-structure interaction (FSI) modeling. The results were presented as longitudinal and...
Design performance characteristics of a social robot companion "Arash" for pediatric hospitals
, Article International Journal of Humanoid Robotics ; Volume 15, Issue 5 , 2018 ; 02198436 (ISSN) ; Shariati, A ; Alemi, M ; Amoozandeh Nobaveh, A ; Khamooshi, M ; Mozaffari, B ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2018
Abstract
This paper presents the design process and construction of a mobile social robot companion "Arash" for educational and therapeutic intervention for children with chronic diseases; one which is based on their interests and needs. This study concentrates on children with cancer who suffer from physical pain caused by both the disease and its treatment. Moreover, cancer treatment causes emotional distress, which can reduce the efficiency of medications. Using social robots to interact with ill children in a hospital environment could decrease their distress, thereby improving the efficiency of the treatment. Arash is a 15 degrees-of-freedom cost effective humanoid mobile robot companion,...
Towards an automatic diagnosis system for lumbar disc herniation: the significance of local subset feature selection
, Article Biomedical Engineering - Applications, Basis and Communications ; 2018 ; 10162372 (ISSN) ; Fayaz, F ; Nikravan, M ; Ahmadi, F ; Dolatabad, M. R ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2018
Abstract
Herniation in the lumbar area is one of the most common diseases which results in lower back pain (LBP) causing discomfort and inconvenience in the patients' daily lives. A computer aided diagnosis (CAD) system can be of immense benefit as it generates diagnostic results within a short time while increasing precision of diagnosis and eliminating human errors. We have proposed a new method for automatic diagnosis of lumbar disc herniation based on clinical MRI data. We use T2-W sagittal and myelograph images. The presented method has been applied on 30 clinical cases, each containing 7 discs (210 lumbar discs) for the herniation diagnosis. We employ Otsu thresholding method to extract the...
Toward a computer aided diagnosis system for lumbar disc herniation disease based on MR images analysis
, Article Biomedical Engineering - Applications, Basis and Communications ; Volume 28, Issue 6 , 2016 ; 10162372 (ISSN) ; Ebrahimzadeh, E ; Izadi, M. R ; Mikaeili, M ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
Abstract
Lumbar disc diseases are the commonest complaint of Lower Back Pain (LBP). In this paper, a new method for automatic diagnosis of lumbar disc herniation is proposed which is based on clinical Magnetic Resonance Images (MRI) data. We use T2-W sagittal and myelograph images. Our method uses Otsu thresholding method to extract the spinal cord from MR images of Lumbar disc. In the next step, a third-order polynomial is aligned on the extracted spinal cords, and in the end of preprocessing step all the T2-W sagittal images are prepared for extracting disc boundary and labeling. After labeling and extracting a ROI for each disc, intensity and shape features are used for classification. The...
Differentiation of inflammatory papulosquamous skin diseases based on skin biophysical and ultrasonographic properties: A decision tree model
, Article Indian Journal of Dermatology, Venereology and Leprology ; Volume 86, Issue 6 , 2020 , Pages 752- ; Yazdani, K ; Ahmad Nasrollahi, S ; Nazari, M ; Darooei, R ; Firooz, A ; Sharif University of Technology
Wolters Kluwer Medknow Publications
2020
Abstract
The biophysical and ultrasonographic properties of the skin change in papulosquamous diseases. Aims: To identify biophysical and ultrasonographic properties for the differentiation of five main groups of papulosquamous skin diseases. Methods: Fifteen biophysical and ultrasonographic parameters were measured by multiprobe adapter system and high-frequency ultrasonography in active lesions and normal control skin in patients with chronic eczema, psoriasis, lichen planus, pityriasis rosea and parapsoriasis/mycosis fungoides. Using histological diagnosis as a gold standard, a decision tree analysis was performed based on the mean percentage changes of these parameters [(lesion-control/control)...
Specific picomolar detection of a breast cancer biomarker her-2/neu protein in serum: electrocatalytically amplified electroanalysis by the aptamer/peg-modified electrode
, Article ChemElectroChem ; Volume 4, Issue 4 , 2017 , Pages 872-879 ; 21960216 (ISSN) ; Kékedy Nagy, L ; Ferapontova, E. E ; Sharif University of Technology
Wiley-VCH Verlag
2017
Abstract
Specific and sensitive electroanalysis of blood-circulating protein cancer biomarkers is often complicated by interference from serum proteins nonspecifically adsorbing at the biosensing interface and masking specific reactions of interest. Here, we have developed an electrocatalytically amplified assay for specific and sensitive analysis of human epidermal growth factor receptor-2 (HER-2/neu, a protein cancer biomarker over-expressed in breast cancers) that allows us to avoid both the interference from bovine serum albumin (BSA) and electrocatalytic amplification of the signal stemming from the specific aptamer−HER-2/neu binding. A HER-2/neu-specific thiolated aptamer sequence was...
Curcumin-Loaded Starch Micro/Nano particles for biomedical application: the effects of preparation parameters on release profile
, Article Starch/Staerke ; Volume 71, Issue 5-6 , 2019 ; 00389056 (ISSN) ; Zahedifar, P ; Bagheri, R ; Solouk, A ; Sharif University of Technology
Wiley-VCH Verlag
2019
Abstract
Although curcumin is highly cytotoxic against cancer cells, its hydrophobicity and fast degradation at physiological pH limit its effective practical application. To prevent such limitations, inexpensive curcumin-loaded starch particles are synthesized in this research. Particles are prepared by water-in-oil (W/O) miniemulsion technique and an adsorption method is used for curcumin loading. Also, encapsulation efficiency (%EE) is improved by using pluronic F-127 in the drug solution. Particles are characterized, swelling studies are performed, and MTT assays against human adipose mesenchymal stem cells (hAMSCs) and MG-63 cells are utilized for investigations. Results indicate that...