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Use of microfluidic organ-on-a-chip systems for the screening and development of phytopharmaceuticals and herbal drugs
, Article Phytopharmaceuticals and Herbal Drugs: Prospects and Safety Issues in the Delivery of Natural Products ; 2023 , Pages 323-339 ; 978-032399125-4 (ISBN); 978-032399369-2 (ISBN) ; Aldhaher, A ; Doseff, A. I ; Alavian, E ; Elnour, A. A. M ; Ashammakhi, N ; Sharif University of Technology
Elsevier
2023
Abstract
Natural products (NPs) and their derivatives constitute an important source of bioactive pharmaceutical compounds. Due to the increasing interest in NPs, finding new approaches for rapid screening of novel chemistries and evaluating their potential toxicity is of paramount significance. The extensive repertoire of NPs and derivatives and their presence as complex mixtures presents challenges at multiple levels, including the screening for the bioactive components and real-time detection of drugs effects. Recent advances in microfluidic approaches such as organ-on-a-chip, Herbochip, microfluidic biochip, and multiorgan-on-chip have been developed to facilitate the real-time detection of drug...
Three-dimensional bioprinting of functional skeletal muscle tissue using gelatin methacryloyl-alginate bioinks
, Article Micromachines ; Volume 10, Issue 10 , 2019 ; 2072666X (ISSN) ; Çelebi Saltik, B ; Barros, N ; Nasiri, R ; Banton, E ; Shamloo, A ; Ashammakhi, N ; Dokmeci, M. R ; Ahadian, S ; Sharif University of Technology
MDPI AG
2019
Abstract
Skeletal muscle tissue engineering aims to fabricate tissue constructs to replace or restore diseased or injured skeletal muscle tissues in the body. Several biomaterials and microscale technologies have been used in muscle tissue engineering. However, it is still challenging to mimic the function and structure of the native muscle tissues. Three-dimensional (3D) bioprinting is a powerful tool to mimic the hierarchical structure of native tissues. Here, 3D bioprinting was used to fabricate tissue constructs using gelatin methacryloyl (GelMA)-alginate bioinks. Mechanical and rheological properties of GelMA-alginate hydrogels were characterized. C2C12 myoblasts at the density 8 × 106 cells/mL...
Kidney-on-a-chip
, Article Principles of Human Organs-on-Chips ; 2023 , Pages 277-314 ; 978-012823536-2 (ISBN); 978-012823610-9 (ISBN) ; Mousavi, A ; Jafari, A ; Savoji, H ; Deliorman, M ; Sukumar, P ; Aldhaher, A ; Qasaimeh, M. A ; Ertas, Y. N ; Ashammakhi, N ; Sharif University of Technology
Elsevier
2023
Abstract
Kidney toxicity represents the most common adverse event resulting from drugs, and its assessment is critical for drug development. The application of two-dimensional (2D) in vitro and animal models to evaluate drug efficacy have their shortcomings due to the lack of representation of in vivo environment for the first, or the difference in drug pharmacokinetics and pharmacodynamics response between animals and human for the latter. In this regard, three-dimensional (3D) microfluidic culture platforms such as kidney-on-chip have shown great promise in recapitulating native tissues in vitro. In recent years, significant attempts have also been made in the modeling of kidney diseases to study...
Gut-on-a-chip: Current progress and future opportunities
, Article Biomaterials ; Volume 255 , 2020 ; Nasiri, R ; Barros, N. R. D ; Tebon, P ; Thakor, J ; Goudie, M ; Shamloo, A ; Martin, M. G ; Khademhosseni, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Organ-on-a-chip technology tries to mimic the complexity of native tissues in vitro. Important progress has recently been made in using this technology to study the gut with and without microbiota. These in vitro models can serve as an alternative to animal models for studying physiology, pathology, and pharmacology. While these models have greater physiological relevance than two-dimensional (2D) cell systems in vitro, endocrine and immunological functions in gut-on-a-chip models are still poorly represented. Furthermore, the construction of complex models, in which different cell types and structures interact, remains a challenge. Generally, gut-on-a-chip models have the potential to...
3D Bioprinting of oxygenated cell-laden gelatin methacryloyl constructs
, Article Advanced Healthcare Materials ; Volume 9, Issue 15 , 2020 ; Darabi, M. A ; Nasiri, R ; Sangabathuni, S ; Ertas, Y. N ; Alem, H ; Hosseini, V ; Shamloo, A ; Nasr, A. S ; Ahadian, S ; Dokmeci, M. R ; Khademhosseini, A ; Ashammakhi, N ; Sharif University of Technology
Wiley-VCH Verlag
2020
Abstract
Cell survival during the early stages of transplantation and before new blood vessels formation is a major challenge in translational applications of 3D bioprinted tissues. Supplementing oxygen (O2) to transplanted cells via an O2 generating source such as calcium peroxide (CPO) is an attractive approach to ensure cell viability. Calcium peroxide also produces calcium hydroxide that reduces the viscosity of bioinks, which is a limiting factor for bioprinting. Therefore, adapting this solution into 3D bioprinting is of significant importance. In this study, a gelatin methacryloyl (GelMA) bioink that is optimized in terms of pH and viscosity is developed. The improved rheological properties...
Brain-on-a-chip: Recent advances in design and techniques for microfluidic models of the brain in health and disease
, Article Biomaterials ; Volume 285 , 2022 ; 01429612 (ISSN) ; Shamloo, A ; Nasiri, R ; de Barros, N. R ; Wang, Z. Z ; Unluturk, B. D ; Libanori, A ; Ievglevskyi, O ; Diltemiz, S. E ; Sances, S ; Balasingham, I ; Seidlits, S. K ; Ashammakhi, N ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Recent advances in biomaterials, microfabrication, microfluidics, and cell biology have led to the development of organ-on-a-chip devices that can reproduce key functions of various organs. Such platforms promise to provide novel insights into various physiological events, including mechanisms of disease, and evaluate the effects of external interventions, such as drug administration. The neuroscience field is expected to benefit greatly from these innovative tools. Conventional ex vivo studies of the nervous system have been limited by the inability of cell culture to adequately mimic in vivo physiology. While animal models can be used, their relevance to human physiology is uncertain and...
Microfluidic-based approaches in targeted cell/particle separation based on physical properties: fundamentals and applications
, Article Small ; Volume 16, Issue 29 , 2020 ; Shamloo, A ; Ahadian, S ; Amirifar, L ; Akbari, J ; Goudie, M. J ; Lee, K ; Ashammakhi, N ; Dokmeci, M. R ; Di Carlo, D ; Khademhosseini, A ; Sharif University of Technology
Wiley-VCH Verlag
2020
Abstract
Cell separation is a key step in many biomedical research areas including biotechnology, cancer research, regenerative medicine, and drug discovery. While conventional cell sorting approaches have led to high-efficiency sorting by exploiting the cell's specific properties, microfluidics has shown great promise in cell separation by exploiting different physical principles and using different properties of the cells. In particular, label-free cell separation techniques are highly recommended to minimize cell damage and avoid costly and labor-intensive steps of labeling molecular signatures of cells. In general, microfluidic-based cell sorting approaches can separate cells using “intrinsic”...
Microengineered poly(HEMA) hydrogels for wearable contact lens biosensing
, Article Lab on a Chip ; Volume 20, Issue 22 , 2020 , Pages 4205-4214 ; Zhang, S ; Cui, Q ; Ni, J ; Wang, X ; Cheng, X ; Alem, H ; Tebon, P ; Xu, C ; Guo, C ; Nasiri, R ; Moreddu, R ; Yetisen, A. K ; Ahadian, S ; Ashammakhi, N ; Emaminejad, S ; Jucaud, V ; Dokmeci, M.R ; Khademhosseini, A ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Microchannels in hydrogels play an essential role in enabling a smart contact lens. However, microchannels have rarely been created in commercial hydrogel contact lenses due to their sensitivity to conventional microfabrication techniques. Here, we report the fabrication of microchannels in poly(2-hydroxyethyl methacrylate) (poly(HEMA)) hydrogels that are used in commercial contact lenses with a three-dimensional (3D) printed mold. We investigated the corresponding capillary flow behaviors in these microchannels. We observed different capillary flow regimes in these microchannels, depending on their hydration level. In particular, we found that a peristaltic pressure could reinstate flow in...
Recent activities in science and technology and the progress of women in physics in the last three years in Iran
, Article AIP Conference Proceedings, Stellenbosch ; Volume 1517 , 2013 , Pages 108-109 ; 0094243X (ISSN); 9780735411388 (ISBN) ; Azad, M. T ; Mahmoudi, N ; Izadipanah, N ; Eshghi, N ; Sharif University of Technology
2013
Abstract
For the 4th IUPAP International Conference of Women in Physics, we report on activities in science and engineering in Iran, and conditions for women in physics, in the three years since the 3rd IUPAP International Conference of Women in Physics was held in 2008. Iran has made prominent advancements and astonishing progress in laser technology, biotechnology, nanotechnology, genetics, computer software and hardware, and robotics. Iranian scientists have been very productive in several experimental fields, such as pharmaceutical, organic, and polymer chemistry. Conditions for women in physics have improved greatly in recent years. A project to improve the environment for learning physics, and...
Lead-free MAGeI3 as a suitable alternative for MAPbI3 in nanostructured perovskite solar cells: a simulation study
, Article Environmental Science and Pollution Research ; Volume 30, Issue 19 , 2023 , Pages 57032-57040 ; 09441344 (ISSN) ; Akhavan, O ; Rabiee, N ; Afshar, E. N ; Zare, E. N ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2023
Abstract
The lead is a heavy metal with hazardous impacts on environment and human life. Lead-free perovskite solar cells have attracted much attention in recent years, due to eco-friendly characteristics. Meanwhile, Pb-containing cells showed the highest efficiencies among the various types of cells. Hence, designing novel Pb-free solar cells with comparable or better performance than the Pb-containing ones is highly required. In this work, a lead-free methyl-ammonium-germanium-iodide (MAGeI3)-based perovskite solar cell with ITO/TiO2/MAGeI3/Spiro-OMeTAD/Ag multilayer nanostructure has been proposed and its main characteristics including open-circuit voltage (VOC) and power conversion efficiency (η)...
Ab initio study of electronic effects in the ZnO/TiO2 core/shell interface: Application in dye sensitized solar cells
, Article RSC Advances ; Vol. 4, issue. 1 , April , 2014 , p. 301-307 ; Nafari, N ; Taghavinia, N ; Sharif University of Technology
2014
Abstract
Core/shell structure of ZnO nanowires coated with a monolayer of TiO 2 is investigated using Density Functional Theory (DFT). The electronic states of the semiconductor is calculated and compared before and after coating of the TiO2 monolayer on a ZnO [101 0] surface. The effect of TiO2 coating induce surface states changes and shifts the conduction and valence band edges to higher energies. Our results, in qualitative agreement with the experimental work of Matt Law et al. (J. Phys. Chem. B, 110, 22652), show an increase in open circuit voltage and a decrease in short circuit current in ZnO/TiO2 core shell dye sensitized solar cells. Regarding the semiconductor density of states (DOS), TiO2...
Analyzing factors effective on the development of relationship commitment
, Article Proceedings of the 2012 International Conference on Artificial Intelligence, ICAI 2012, 16 July 2012 through 19 July 2012 ; Volume 1 , July , 2012 , Pages 398-404 ; 1601322186 (ISBN) ; 9781601322180 (ISBN) ; Lotfi, N ; Karami, N ; Sharif University of Technology
2012
Abstract
Due to the important role of commitment and trust in the relationship marketing, the factors which can directly result in a committed relationship along with the factors which can influence the commitment through influencing trust, according to the model of commitment and trust by (Morgan & Hunt, 1994) have been introduced and their level of importance has been investigated here. The article uses fuzzy cognitive maps (FCMs) in the proposed model to find the most important paths leading to relationship commitment. The FCM analyzes the responses of a group of 30 people including general practitioners in dentistry, managers of dental departments in some of the public clinics and hospitals who...
Morphological dependence of light backscattering from metallic back reflector films: Application in dye-sensitized solar cells
, Article Physica Status Solidi (A) Applications and Materials Science ; Volume 212, Issue 4 , January , 2015 , Pages 785-790 ; 18626300 (ISSN) ; Ghazyani, N ; Taghavinia, N ; Sharif University of Technology
Wiley-VCH Verlag
2015
Abstract
Conventionally, a film of TiO2 particles of 300 nm size is employed in Dye-sensitized solar cells (DSCs) as the back reflector film to enhance the light harvesting. Perfect reflectance of silver in visible and near infrared motivates to investigate its potential as the material for the light back reflector film in DSCs. In this study, light back reflector films consisting of 300 nm-sized silver particles, as well as vacuum evaporated silver flat film, were fabricated and compared to 300 nm-sized rutile-type TiO2 particulate reflector film to study their optical aspects. Conventional TiO2 rutile-type particulate film demonstrates slightly lower performance...
Monolithic dye sensitized solar cell with metal foil counter electrode
, Article Organic Electronics ; Volume 57 , June , 2018 , Pages 194-200 ; 15661199 (ISSN) ; Taghavinia, N ; Ghazyani, N ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Monolithic dye-sensitized solar cells are conventionally fabricated using carbon composite layer as the counter electrode. In the current research, the brittle carbon composite layer is replaced with a metal foil, aiming to decrease the device series resistance and using less catalyst material in counter electrode. This metallic structure has also an advantage of mechanical strength and decreases the fabrication complexity. The counter electrode is prepared by electrodepositing Cr film followed by electrodepositing Pt nanoparticles on a metal foil. As the porous spacer layer, different composite layers of SiO2, TiO2, and Al2O3 are investigated and the best results are obtained for TiO2...
A compact versatile microbial fuel cell from paper
, Article ASME 2013 11th Int. Conf. on Fuel Cell Science, Eng. and Technology Collocated with the ASME 2013 Heat Transfer Summer Conf. and the ASME 2013 7th Int. Conf. on Energy Sustainability, FUELCELL 2013 ; 2013 ; 9780791855522 (ISBN) ; Hashemi, N ; Hashemi, N ; Sharif University of Technology
2013
Abstract
Microbial fuel cells (MFCs) have been a potential green energy source for a long time but one of the problems is that either the technology must be used on a large scale or special equipment have been necessary to keep the fuel cells running such as syringe pumps. Paper-based microbial fuel cells do not need to have a syringe pump to run and can run entirely by themselves when placed in contact with the fluids that are necessary for it to run. Paper-based microbial fuel cells are also more compact than traditional MFCs since the device doesn't need any external equipment to run. The goal of this paper is to develop a microbial fuel cell that does not require a syringe pump to function. This...
Decentralized model predictive voltage control of islanded DC microgrids
, Article 11th Power Electronics, Drive Systems, and Technologies Conference, PEDSTC 2020, 4 February 2020 through 6 February 2020 ; 2020 ; Mahdian Dehkordi, N ; Sadati, N ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
This paper proposes a novel decentralized control approach for islanded direct-current (DC) microgrids (MGs) based on model predictive control (MPC) to regulate the distributed generation unit (DGU) output voltages, i.e. the voltages of the point of common coupling (PCC). A local controller is designed for each DGU, in the presence of uncertainties, disturbances, and unmodeled dynamics. First, a discrete-time state-space model of an MG is derived. Afterward, an MPC algorithm is designed to perform the PCC voltage control. The proposed MPC scheme ensures that the PCC voltages remain within an acceptable range. Several simulation studies have been conducted to illustrate the effectiveness of...
Intelligent optimal feed-back torque control of a 6DOF surgical rotary robot
, Article 11th Power Electronics, Drive Systems, and Technologies Conference, PEDSTC 2020, 4 February 2020 through 6 February 2020 ; 2020 ; Ebrahimi Toulkani, N ; Zhilakzadeh, N ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Sophisticated surgeons are widely indicating the use of surgical robots in order to reject human error, increase precision, and speed. Among well-known robotic mechanisms, parallel robots are broadly more investigated regarding their special characters as higher acceleration, speed, and accuracy, and less weight. Specific surgical procedures confine, and restrict their workspace, while controlling and validating the robots are complicated regarding to their complex dynamic. To this end, in this paper, a 6-DOF robot, with rotary manipulators, is designed and controlled. Addressing nonlinearity of parallel robots, an innovative methodology is formulated to robustly penalize the error of...
Semi-Real evaluation, and adaptive control of a 6DOF surgical robot
, Article 11th Power Electronics, Drive Systems, and Technologies Conference, PEDSTC 2020, 4 February 2020 through 6 February 2020 ; 2020 ; Ebrahimi Toulkani, N ; Zhilakzadeh, N ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Sophisticated surgeons are widely indicating the use of surgical robots in order to reject human error, increase precision, and speed. Among well-known robotic mechanisms, parallel robots are broadly more investigated regarding their special characters as higher acceleration, speed, and accuracy, and less weight. Specific surgical procedures confine and restrict their workspace, while controlling and validating the robots are complicated based on their complex dynamic. To this end, in this paper, a 6-DOF robot, with linear manipulators, is designed and controlled. Addressing the inherent nonlinearity of the robot mechanism, an adaptive PID manipulator is employed and validated with nonlinear...
Modeling superconductive fault current limiter using constructive neural networks
, Article 2007 IEEE International Symposium on Industrial Electronics, ISIE 2007, Caixanova - Vigo, 4 June 2007 through 7 June 2007 ; 2007 , Pages 2859-2863 ; 1424407559 (ISBN); 9781424407552 (ISBN) ; Sadati, N ; Hosseini, M. N ; Sharif University of Technology
2007
Abstract
Although so many advances have been proposed in the field of artificial intelligence and superconductivity, there are few reports on their combination. On the other hand, because of the nonlinear and multivariable characteristics of the superconductive elements and capabilities of neural networks in this field, it seems useful to apply the neural networks to model and control the superconductive phenomena or devices. In this paper, a new constructive neural network (CNN) trained by two different optimization algorithms; back-propagation and genetic algorithm, is proposed which models the behavior of the superconductive fault current limiters (SFCLs). Simulation results show that the proposed...
Satellite attitude tracking using optimal neuro-controller
, Article 2003 IEEE Aerospace Conference, Big Sky, MT, 8 March 2003 through 15 March 2003 ; Volume 6 , 2003 , Pages 2663-2669 ; 1095323X (ISSN); 078037651X (ISBN); 9780780376519 (ISBN) ; Sadati, N ; Tehrani, N. D ; Sharif University of Technology
2003
Abstract
In this paper, a new control strategy for optimal attitude tracking control of a multivariable satellite system has been presented. The approach is based on a Multilayer Perceptron Neural Network (MLPNN) and a classical PD Controller for its initial stabilization. It is shown how the network can be employed as a multivariable self-organizing and self-learning controller in conjunction with a PD controller for attitude control of a satellite. By using three thrusters and quaternion for kinematics representation, the attitude dynamics of the satellite has been presented. In contrast to the previous classical approaches, it is shown how this controller can be carried out in an on-line manner...