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Synthesis and in Vitro/in Vivo Evaluation of Bioprinted and Core-Shell Systems Containing Proteoglycan Nanoparticle and Growth Factor for Skin Tissue Regeneration
, Ph.D. Dissertation Sharif University of Technology ; Simchi, Abdolreza (Supervisor) ; Shokrgozar, Mohammad Ali (Supervisor) ; Tamjid, Elnaz (Co-Supervisor)
Abstract
Tissue engineering has the potential to revolutionize our health care system. Conceptually, lost or malfunctioning tissues will be replaced by man-made biological substitutes to restore, maintain, or improve function. Tissue engineering has already shown great promise to contribute to treatments of a myriad of diseases including osteoarthritis, cancer, diabetes, skin burns, cardiovascular conditions and various traumatic injuries. Tissue engineering is a highly multidisciplinary discipline that demands integration of knowledge, tools and skills from biology, chemistry, engineering and medicine. Integrating nano- and microtechnologies into clinically sized implants represents a major...
Fabrication and Optimizing a Bilayer Scaffold with the Ability to Release Growth Factors in Aim to Treating Injuries in Tissue Engineering
, M.Sc. Thesis Sharif University of Technology ; Shamloo, Amir (Supervisor) ; Hosseini, Vahid (Supervisor)
Abstract
Skin, as the largest organ of the body and the first protector against external injuries, plays an important role in maintaining human health. Therefore, providing a method for complete treatment of skin lesions is very important. In the last century, tissue engineering approaches, with the introduction of skin scaffolds, have been instrumental in the process of skin tissue regeneration and treatment. The aim of the present study is to construct an optimal bilayer scaffold to mimic the two outer layer of the skin (epidermis and dermis). Besides, the effects of placenta extract on acceleration of wound healing was investigated by an in-vivo test. both layer of scaffold are porous hydrogels,...
Design and Optimization of Hydrofiber Dressings Containing Borosilicate Bioactive Glass Doped with Zinc for Wound Healing
,
M.Sc. Thesis
Sharif University of Technology
;
Mashayekhan, Shohreh
(Supervisor)
;
Karimi, Afzal
(Supervisor)
Abstract
Wound healing is a complex and regular process. It makes more challenge when the volume of wound exudate becomes uncontrollable. To solve this problem, hydrofiber wound dressings which contain carboxymethyl cellulose fibers are being used. Fast absorption and keeping the moisture in balance specially in chronic wounds, is one of the major features of hydrofiber wound dressings. In this research, which was conducted with the aim of investigating the synergy effect of active glasses and Hydrofiber commercial wound dressing for the healing of skin wounds, especially chronic wounds, the sol-gel method has been used to synthesize bioactive glasses based on borosilicate, replacing a part of CaO...
Determination of Pressure Drop Due to Skin Effect In Various Times and Simulation Under Steady/Transient Condition and Sensitivity Analysis On the Effective Parameters
, M.Sc. Thesis Sharif University of Technology ; Jamshidi, Saeed (Supervisor)
Abstract
Any factor that causes an additional pressure drop to the reservoir is called damage. Damages due to drilling, well completion and production can cause additional pressure drop to formation. In this study, damage caused by mechanical damage, well deviation from vertical (angled well), partially completed well and horizontal well and formation damage behavior during the occurrence of water and gas coning phenomenon have been investigated by simulation and the results have been verified with the analytical models available for calculating the formation skin factor. Also, by studying and examining the data and the results obtained from the simulation of the horizontal well skin factor in a data...
Compact closed form model for skin and proximity effect in multiwall carbon nanotube bundles as GSI interconnects
, Article IEEE Transactions on Electron Devices ; Vol. 61, issue. 8 , July , 2014 , p. 2899-2904 ; Sarvari, R ; Sharif University of Technology
Abstract
Closed form model for skin and proximity effect is necessary for GSI interconnects. In this paper, exact formulation for current distribution inside multiwall carbon nanotube (MWCNT) bundles is derived using multiconductor transmission line model. The current distribution is different from copper wires and it is geometry dependent because of kinetic inductance and quantum capacitance. This current distribution is used to compute and formulate high frequency resistance of MWCNT bundles
Series solution for heat transfer of continuous stretching sheet immersed in a micropolar fluid in the existence of radiation
, Article International Journal of Numerical Methods for Heat and Fluid Flow ; Volume 23, Issue 2 , 2013 , Pages 289-304 ; 09615539 (ISSN) ; Kimiaeifar, A ; Bagheri, D ; Sharif University of Technology
2013
Abstract
Purpose - The purpose of this paper is to study a two-dimensional steady convective flow of a micropolar fluid over a stretching sheet in the presence of radiation with constant temperature. Design/methodology/approach - The corresponding momentum, microrotation and energy equations are analytically solved using homotopy analysis method (HAM). Findings - To validate the method, investigate the accuracy and convergence of the results, a comparison with existing numerical and experimental results is done for several cases. Finally, by using the obtained analytical solution, for the skin-friction coefficient and the local Nusselt number as well as the temperature, velocity and angular velocity,...
Accurate numerical model for surface scattering, grain boundary scattering, and anomalous skin effect of copper wires
, Article Proceedings - Winter Simulation Conference ; January , 2013 , Pages 209-210 ; 08917736 (ISSN) ; 9781467348416 (ISBN) ; Sarvari, R ; Akbarzadeh, A ; Rostami, M ; Sharif University of Technology
2013
Abstract
In this paper we have studied both DC size effect and anomalous skin effect caused by surface and grain boundary scattering on the resistivity of Cu thin films by a Monte Carlo method. Contribution of each scattering mechanism and the interaction between them are analyzed separately. A simple and fast numerical recursive method is also introduced to guess the structure of electric field and distribution of current inside the thin film to evaluate the surface resistance instead of complicated analytical formulas
Electrospinning of nanodiamond-modified polysaccharide nanofibers with physico-mechanical properties close to natural skins
, Article Marine Drugs ; Volume 14, Issue 7 , 2016 ; 16603397 (ISSN) ; Mahmoudi, N ; Rezaie Anaran, F ; Simchi, A ; Sharif University of Technology
MDPI AG
Abstract
Electrospinning of biopolymers has gained significant interest for the fabrication of fibrous mats for potential applications in tissue engineering, particularly for wound dressing and skin regeneration. In this study, for the first time, we report successful electrospinning of chitosan-based biopolymers containing bacterial cellulous (33 wt %) and medical grade nanodiamonds (MND) (3 nm; up to 3 wt %). Morphological studies by scanning electron microscopy showed that long and uniform fibers with controllable diameters from 80 to 170 nm were prepared. Introducing diamond nanoparticles facilitated the electrospinning process with a decrease in the size of fibers. Fourier transform infrared...
Real-time multiple face detection and tracking
, Article 2009 14th International CSI Computer Conference, CSICC 2009, 20 October 2009 through 21 October 2009 ; 2009 , Pages 379-384 ; 9781424442621 (ISBN) ; Fotouhi, M ; Kasaei, S ; Sharif University of Technology
Abstract
In recent years, processing the images that contain human faces has been a growing research interest because of establishment and development of automatic methods especially in security applications, compression, and perceptual user interface. In this paper, a new method has been proposed for multiple face detection and tracking in video frames. The proposed method uses skin color, edge and shape information, face detection, and dynamic movement analysis of faces for more accurate real-time multiple face detection and tracking purposes. One of the main advantages of the proposed method is its robustness against usual challenges in face tracking such as scaling, rotation, scene changes, fast...
New method for assessing the utility harmonic impedance based on fuzzy logic
, Article IET Generation, Transmission and Distribution ; Volume 11, Issue 10 , 2017 , Pages 2448-2456 ; 17518687 (ISSN) ; Mokhtari, H ; Sharif University of Technology
Abstract
This study proposes a novel non-invasive method for estimating the utility harmonic impedance. Since the major concern about non-invasive methods is the dependency of the accuracy of the results on background harmonic fluctuations, proper measured samples are selected using a three-point data selection technique to increase the method accuracy. Then, a new non-invasive method for the evaluation of the utility harmonic impedance at a point of common coupling (PCC) based on fuzzy logic is presented. In the proposed method, fuzzy logic is applied to the constrained recursive least squares algorithm (CRLS) by designing a set of fuzzy if-then rules. Due to the changes in the quantities at a...
Application of a mathematical method in calculation of the skin variation during a real field acidizing operation
, Article Chemical Engineering Science ; Volume 192 , 2018 , Pages 829-839 ; 00092509 (ISSN) ; Jamshidi, S ; Jahangiri, H. R ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The efficiency of an acidizing operation is usually assessed through ordinary well testing methods. These methods are performed only after the acidizing operation, and it is difficult to monitor and evaluate real-time efficiency of acidizing operation. Understanding the performance of the acidizing during the service, by analysis of the acidizing data is a viable approach to this costly and challenging process. The estimation of the skin changes needs an appropriate mathematical method that can handle the main aspects of an acidizing operation. It is tedious to model a real acidizing operation due to the heterogeneity of the reservoir, an unknown reaction rate of acid in reservoir condition,...
Neuro-Skins: Dynamics, plasticity and effect of neuron type and cell size on their response
, Article Neural Processing Letters ; 2018 , Pages 1-23 ; 13704621 (ISSN) ; Shafiei Dizaji, M ; Sharif University of Technology
Springer New York LLC
2018
Abstract
We are introducing a new type of membrane, called neuro-skin or neuro-membrane. It is comprised of neurons embedded in a plastic membrane. The skin is smart and adaptive and is capable of providing desirable response to inputs intelligently. This way, the neuro-skin can be considered as a new type of neural network with adaptivity and learning capabilities. However, in this paper, only the response of neuro-skins to a dynamic input is studied. The membrane is modelled by nonlinear dynamic finite elements. Each finite element is considered as a cell of the neuro-skin which has a neuron. The neuron is the intelligent nucleus of the element. So, the finite elements are called finite...
Neuro-Skins: Dynamics, Plasticity and effect of neuron type and cell size on their response
, Article Neural Processing Letters ; Volume 49, Issue 1 , 2019 , Pages 19-41 ; 13704621 (ISSN) ; Shafiei Dizaji, M ; Sharif University of Technology
Springer New York LLC
2019
Abstract
We are introducing a new type of membrane, called neuro-skin or neuro-membrane. It is comprised of neurons embedded in a plastic membrane. The skin is smart and adaptive and is capable of providing desirable response to inputs intelligently. This way, the neuro-skin can be considered as a new type of neural network with adaptivity and learning capabilities. However, in this paper, only the response of neuro-skins to a dynamic input is studied. The membrane is modelled by nonlinear dynamic finite elements. Each finite element is considered as a cell of the neuro-skin which has a neuron. The neuron is the intelligent nucleus of the element. So, the finite elements are called finite...
Low cost flexible pressure sensor using laser scribed GO/RGO periodic structure for electronic skin applications
, Article Superlattices and Microstructures ; Volume 140 , 2020 ; Mohammadpour, R ; Asadian, E ; Paryavi, M ; Rafii Tabar, H ; Sasanpour, P ; Sharif University of Technology
Academic Press
2020
Abstract
Considering electronic skin applications, a pressure sensor based on periodic structure of graphene oxide-reduced graphene oxide (GO-rGO) has been designed and fabricated based on a low cost direct laser writing technique by utilizing the laser diode of DVD drive's pickup head. The optimization of sensor structure has been performed using computational modelling through Finite Element Method (FEM) in the COMSOL environment. The optimized structure is fabricated based on the deposition of thin layer of GO on the surface of Kapton and the pattering is performed by laser irradiation. The fabricated sensor structure has been characterized structurally and functionally. The results show that the...
Heat transfer enhancement of ferrofluid flow within a wavy channel by applying a non-uniform magnetic field
, Article Journal of Thermal Analysis and Calorimetry ; Volume 139, Issue 5 , 2020 , Pages 3331-3343 ; Biglarian, M ; Rabienataj Darzi, A. A ; Farhadi, M ; Hassanzadeh Afrouzi, H ; Toghraie, D ; Sharif University of Technology
Springer Netherlands
2020
Abstract
This paper presents the effects of a non-uniform magnetic field on the hydrodynamic and thermal behavior of ferrofluid flow in a wavy channel by 3D numerical simulation. The wavy surfaces at the top and bottom of the channel are heated by constant heat fluxes. Moreover, the sidewalls are adiabatic. In the wavy section, in the perpendicular direction of the main flow, the magnetic field that linearly varies along the direction of the main flow is applied. The mathematical model that is consistent with the principles of ferrohydrodynamics and magnetohydrodynamics is used for the problem formulation. The results indicate that the wavy wall enhances the heat transfer rate on the bottom of the...
Data-driven approach for evaluation of formation damage during the injection process
, Article Journal of Petroleum Exploration and Production Technology ; Volume 10, Issue 2 , 2020 , Pages 699-710 ; Jahangiri, H. R ; Shahrabadi, A ; Sharif University of Technology
Springer
2020
Abstract
Waterflooding is among the most common oil recovery methods which is implemented in the most of oil-producing countries. The goal of a waterflooding operation is pushing the low-pressure remained oil of reservoir toward the producer wells to enhance the oil recovery factor. One of the important objects of a waterflooding operation management is understanding the quality of connection between the injectors and the producers of the reservoir. Capacitance resistance model (CRM) is a data-driven method which can estimate the production rate of each producer and the connectivity factor between each pair of wells, by history matching of the injection and production data. The estimated connectivity...
Multi-view face detection and recognition under varying illumination conditions by designing an illumination effect cancelling filter
, Article 12th AES Symposium on New Trends in Audio and Video, NTAV 2008, Joined with the 12th IEEE Conference on Signal Processing: Algorithms, Architectures, Arrangements, and Applications, SPA 2008, Poznan, 25 September 2008 through 27 September 2008 ; 2008 , Pages 27-32 ; 9781457716607 (ISBN) ; Fatemizadeh, E ; Sharif University of Technology
2008
Abstract
This paper presents a novel approach for detection and recognition of multi-view faces whose location is unknown and the illumination conditions are varying. The detection of faces is accomplished after canceling the effect of the various illumination conditions by using a proposed filter. Because of the independency of the approach to skin color of face, the persons with every kind of skin colors are detected even in completely dark environments. Next, the detected faces are recognized. It is a well known technique to combine the feature based methods with the template based methods in face recognition. Our experiments show that we can combine some proposed aspects of the feature based...
A contourlet-based face detection method in color images
, Article 3rd IEEE International Conference on Signal Image Technologies and Internet Based Systems, SITIS'07, Jiangong Jinjiang, Shanghai, 16 December 2007 through 18 December 2007 ; 2007 , Pages 727-732 ; 9780769531229 (ISBN) ; Jamzad, M ; Sharif University of Technology
2007
Abstract
The first step of any face processing system is detecting the location in images where faces are present. In this paper we present an upright frontal face detection system based on the multi-resolution analysis of the face. In this method firstly, skin-color information is used to detect skin pixels in color images; then, the skin-region blocks are decomposed into frequency sub-bands using contourlet transform. Features extracted from sub-bands are used to detect face in each block. A multi-layer perceptrone (MLP) neural network was trained to do this classification. To decrease false positive detection we use eyes and lips template matching. These templates achieved by averaging...
Modification of bacterial cellulose/keratin nanofibrous mats by a tragacanth gum-conjugated hydrogel for wound healing
, Article International Journal of Biological Macromolecules ; Volume 134 , 2019 , Pages 280-289 ; 01418130 (ISSN) ; Tamjid, E ; Eslahi, N ; Simchi, A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
To enhance physicomechanical properties and bioactivity of fibrous membranes for wound dressing and tissue engineering applications, novel composite scaffolds consisting of fibrous mats and thermosensitive hydrogel particles were prepared by concurrent electrospinning and electrospraying technique. The composite scaffolds were composed of keratin/bacterial cellulose fibers (150 ± 43 nm) which are hybridized with hydrogel particles (500 nm to 2 μm) based on nonionic triblock copolymers conjugated with Tragacanth gum (TG). FTIR and H-NMR studies indicated ester reactions between carboxylated copolymers and TG through carbodiimide crosslinker chemistry. The hydrogel particles were uniformly...
Natural compounds for skin tissue engineering by electrospinning of nylon-Beta vulgaris
, Article ASAIO Journal ; Volume 64, Issue 2 , 2018 , Pages 261-269 ; 10582916 (ISSN) ; Mahmoudifard, M ; Kehtari, M ; Babaie, A ; Hamedi, S ; Mirzaei, S ; Soleimani, M ; Hosseinzadeh, S ; Sharif University of Technology
Lippincott Williams and Wilkins
2018
Abstract
Natural compounds containing polysaccharide ingredients have been employed as candidates for treatment of skin tissue. Herein, for the first time, electrospinning setup was proposed to fabricate an efficient composite nanofibrous structure of Beta vulgaris (obtained from Beet [Chenopodiaceae or Amaranthaceae]) belonged to polysaccharides and an elastic polymer named nylon 66 for skin tissue engineering. Both prepared scaffolds including noncomposite and composite types were studied by Scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, mechanical assay, and contact angle. Scanning electron microscope examinations have approved the uniform and homogeneous...