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A High Performance MRAM Cell Through Single Free-Layer Dual Fixed-Layer Magnetic Tunnel Junction
, Article IEEE Transactions on Magnetics ; Volume 58, Issue 12 , 2022 ; 00189464 (ISSN) ; Tabandeh, M ; Shouraki, S. B ; Patooghy, A ; Rajaei, R ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
As technology size scales down, magnetic tunnel junctions (MTJs) as a promising technology are becoming more and more sensitive to process variation, especially in oxide barrier thickness. Process variation particularly affects the cell resistance and the critical switching current for the smaller dimensions. This article proposes an MTJ cell with one free and two pinned layers, which highly improves the process variation robustness. By employing the spin transfer torque (STT)-spin-Hall effect (SHE) switching method, our proposed MTJ cell improves the switching speed and lowers the switching power consumption. Per simulations, an MRAM cell built with the proposed MTJ cell offers up to 36%...
Performance analysis of heterogeneous cellular caching networks with overlapping small cells
, Article IEEE Transactions on Vehicular Technology ; Volume 71, Issue 2 , 2022 , Pages 1941-1951 ; 00189545 (ISSN) ; Khalaj, B. H ; Xiao, M ; Skoglund, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
Caching at network edges has attracted more and more research interests recently for the purpose of alleviating the network traffic pressure especially in backhaul links and improving user experience. We study Heterogeneous Cellular Caching Networks (HCCNs) consisting of macro cells in which $N$ small cell base stations (SBSs) equipped with cache memory operate in conjunction with the macro cell base station (MBS). We provide closed-form expressions of the MBS and SBSs utilization factors and average user-experienced-delay in HCCNs with overlapping coverage regions, considering general traffic models for the request arrivals based on the Independent Reference Model (IRM) and renewal traffic...
Optimized kalman filter based on second momentum and triple rectangular for cell tracking on sequential microscopic images
, Article 22nd Iranian Conference on Biomedical Engineering, 25 November 2015 through 28 November 2015 ; 2015 , Pages 251-256 ; 9781467393515 (ISBN) ; Fatemizadeh, E ; Setarehdan, S. K ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
Cell dynamics and motion stages are very important issues in the biological cell investigation in this novel method, we propose a novel method based on Kalman filter and second momentum for tracking cells on Sequential Microscopic Images. In proposed manner at first, we select a cell and cut covering rectangle. in the next step, we predict rectangle center of the cell in Next frame based on a modeling of velocity-acceleration using Kalman filter. The rectangle with triple covering area of previous cell rectangle and predicting center by Kalman filter is considered as a searching area. So, if all objects in the search areas have second momentum error less than threshold, it is selected as a...
Overlapped cells separation algorithm based on morphological system using distance minimums in microscopic images
, Article 22nd Iranian Conference on Biomedical Engineering, 25 November 2015 through 28 November 2015 ; 2015 , Pages 263-268 ; 9781467393515 (ISBN) ; Fatemizadeh, E ; Setarehdan, S. K ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
It is important to distinguish overlapped cell for tracking and segmentation biological cells from images. In this research, a novel or comprehensive method is provided with morphological features of cell and minimum distance for overlapped cells separation (OCS). it's necessary to say that this algorithm is not based on type and number of Overlapped cells. In this presented method based on a distance chart. At first, every cell or rectangle of cell is separated of the original image. Also, multiplex cell is distinguished by using minimum perimeter polygon (MPP) method. Distance chart is achieved on the base of morphological procedure and Computing of cell boundary distance to Cell middle...
Collaboration alignment in distributed interference management in uplink cellular systems
, Article 2016 IEEE International Symposium on Information Theory, 10 July 2016 through 15 July 2016 ; Volume 2016-August , 2016 , Pages 1456-1460 ; 21578095 (ISSN) ; 9781509018062 (ISBN) ; Maddah Ali, M. A ; Shariatpanahi, S. P ; Khalaj, B. H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
We consider a cellular wireless system including several interfering multi-user multi-antenna uplink channels, where the base station of each cell has to locally recover the messages of its corresponding users. We use a linear Wyner model, where each base station experiences interference only from the users in the two neighboring cells. Each base station is connected to the two nearby base stations through a backhaul link. The objective is to achieve the maximum degrees of freedom per cell, with minimum aggregated load in the backhaul. We propose a successive cooperative alignment scheme, in which each base station forms backhaul messages by combining the previous received backhaul messages...
Chitosan-gelatin sheets as scaffolds for muscle tissue engineering
, Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 43, Issue 2 , Nov , 2015 , Pages 124-132 ; 21691401 (ISSN) ; Mashayekhan, S ; Nazaripouya, A ; Naji, M ; Hunkeler, D ; Rajabi Zeleti, S ; Sharifiaghdas, F ; Sharif University of Technology
Informa Healthcare
2015
Abstract
Hydrogels made of natural polymers [chitosan (CS) and gelatin (G)] have been prepared having mechanical properties similar to those of muscle tissues. In this study, the effect of polymer concentration and scaffold stiffness on the behavior of seeded muscle-derived cells (MDCs) on the CS-G hydrogel sheets has been evaluated. Both variables were found to be important in cell viability. Viability was assessed by observation of the cell morphology after 1 day as well as a 14-day MTT assay. The CS-G hydrogels were characterized using Fourier transform infrared (FTIR) analysis, which revealed evidences of strong intermolecular interactions between CS and G. Hydrogel samples with intermediate...
Continuum model of actin-myosin flow
, Article 2013 20th Iranian Conference on Biomedical Engineering, ICBME 2013 ; December , 2013 , Pages 98-102 ; Firoozabadi, B ; Saidi, M. S ; Sharif University of Technology
IEEE Computer Society
2013
Abstract
The front part of a cell is divided to two regions called lamellum and lamellipodium (lamellipodial). This part plays an essential role for cell migration. Indeed, there are many protein filaments called actin in lamellum and lamellipodium, which induce the cell motion with polymerization in the leading edge of the cell. The actin filaments adhere to the extracellular matrix (ECM) by means of focal adhesions and they have contact by myosin motor proteins. The myosin motor proteins cause actin retrograde and anterograde flow exerted contractile stress on them. The focal adhesions exert frictional stress on the actin filaments. In this work, we developed a two-dimensional continuum model of...
Using intra-line level pairing for graceful degradation support in PCMs
, Article Proceedings of IEEE Computer Society Annual Symposium on VLSI, ISVLSI, 8 July 2015 through 10 July 2015 ; Volume 07-10-July-2015 , 2015 , Pages 527-532 ; 21593469 (ISSN) ; 9781479987184 (ISBN) ; Sarbazi Azad, H ; Sharif University of Technology
IEEE Computer Society
2015
Abstract
In Phase-Change Memory (PCM), the number of writes a cell can take before wearing-out is limited and highly varied due to unbalanced write traffic and process variation. After the failure of weak cells and in presence of large number of failed lines, some techniques have been proposed to further prolong the lifetime of a PCM device by remapping failed lines to spares and salvage a PCM device with graceful degradation. Others rely on handling failures through inter-line pairing. Observations reveal that most of cells in a line are healthy when the line is marked as faulty by any of these proposals. To overcome this deficiency, we propose Intra-line Level Pairing(ILP), a technique that...
Investigation of a Novel Microfluidic Device for Label-Free Ferrohydrodynamic Cell Separation on a Rotating Disk
, Article IEEE Transactions on Biomedical Engineering ; Volume 67, Issue 2 , 2020 , Pages 372-378 ; Besanjideh, M ; Sharif University of Technology
IEEE Computer Society
2020
Abstract
Negative magnetophoresis is a novel and attractive method for continuous microparticle sorting inside a magnetic medium. In this method, diamagnetic particles are sorted based on their sizes using magnetic buoyancy force and without any labeling process. Although this method provides some attractive features, such as low-cost fabrication and ease of operation, there are some obstacles that adversely affect its performance, especially for biological applications. Most types of magnetic media, such as ferrofluids, are not biocompatible, and the time-consuming process of sample preparation can be threatening to the viability of the cells within the sample. Furthermore, in this method, both the...
Joint cell muting and user scheduling in multicell networks with temporal fairness
, Article Wireless Communications and Mobile Computing ; Volume 2018 , 2018 ; 15308669 (ISSN) ; Akar, N ; Khalaj, B. H ; Sharif University of Technology
Hindawi Limited
2018
Abstract
A semicentralized joint cell muting and user scheduling scheme for interference coordination in a multicell network is proposed under two different temporal fairness criteria. In the proposed scheme, at a decision instant, each base station (BS) in the multicell network employs a cell-level scheduler to nominate one user for each of its inner and outer sections and their available transmission rates to a network-level scheduler which then computes the potential overall transmission rate for each muting pattern. Subsequently, the network-level scheduler selects one pattern to unmute, out of all the available patterns. This decision is shared with all cell-level schedulers which then forward...
Fabrication of a highly ordered hierarchically designed porous nanocomposite via indirect 3D printing: Mechanical properties and in vitro cell responses
, Article Materials and Design ; Volume 88 , 2015 , Pages 924-931 ; 02641275 (ISSN) ; Simchi, A ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Design and development of biodegradable scaffolds with highly uniform and controlled internal structure that stimulate tissue regeneration are the focus of many studies. The aim of this work is to apply a modified three-dimensional (3D) printing process to fabricate polymer-matrix composites with controlled internal architecture. Computationally-designed plaster molds with various pore sizes in the range of 300-800. μm were prepared by employing 3D printing of a water-based binder. The molds were converted to ε-polycaprolactone (PCL) and PCL/bioactive glass (BG) composite scaffolds by solvent casting and freeze drying methods. Optical and electron microscopy studies revealed that the pore...
Curcumin-reduced graphene oxide sheets and their effects on human breast cancer cells
, Article Materials Science and Engineering C ; Volume 55 , 2015 , Pages 482-489 ; 09284931 (ISSN) ; Akhavan, O ; Sadrnezhaad, S. K ; Ahadian, M. M ; Shirolkar, M. M ; Wang, H. Q ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Curcumin (as a natural reductant material) was utilized for green reduction and functionalization of chemically exfoliated graphene oxide (GO) sheets. The π-π attachment of the curcumin molecules onto the curcumin-reduced graphene oxide (rGO) sheets was confirmed by Raman and Fourier transform infrared spectroscopies. Zeta potential of the GO sheets decreased from about - 40 mV to - 20 mV, after the green reduction and functionalization. The probable cytotoxicity of the curcumin-rGO sheets was studied through their interactions with two human breast cancer cell lines (MDA-MB-231 and SKBR3 cell lines) and a normal cell line (mouse fibroblast L929 cell line). The curcumin-rGO sheet with...
Effect of formulation factors on the bioactivity of glucose oxidase encapsulated chitosan-alginate microspheres: In vitro investigation and mathematical model prediction
, Article Chemical Engineering Science ; Volume 125 , March , 2015 , Pages 4-12 ; 00092509 (ISSN) ; Cheng, J ; Wu, X. Y ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Higher reactive oxygen species (ROS) levels in cancer cells than normal cells have long been recognized, which makes cancer cells more susceptible to excess ROS. Thus oxidation (also called pro-oxidant) therapy has been explored as new cancer therapy regimens. To produce additional ROS, e.g. H2O2 in situ within tumor, we encapsulated glucose oxidase in chitosan-coated alginate-calcium microspheres (GOX-MS) for locoregional treatment and demonstrated its efficacy against cancer cells in vitro and in vivo. Owing to the complex biological functions of ROS, the production rate and amount of H2O2 are critical to achieve therapeutic benefits without causing normal tissue toxicity. This work was...
ZnFe2O4 nanoparticles as radiosensitizers in radiotherapy of human prostate cancer cells
, Article Materials Science and Engineering C ; Volume 46 , January , 2015 , Pages 394-399 ; 09284931 (ISSN) ; Akhavan, O ; Khoei, S ; Shokri, A. A ; Hajikarimi, Z ; Khansari, N ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Nanoparticles of high-Z elements exhibit stronger photoelectric effects than soft tissues under gamma irradiation. Hence, they can be used as effective radiosensitizers for increasing the efficiency of current radiotherapy. In this work, superparamagnetic zinc ferrite spinel (ZnFe2O4) nanoparticles were synthesized by a hydrothermal reaction method and used as radiosensitizers in cancer therapy. The magnetic nanoparticles showed fast separation from solutions (e.g., ~ 1 min for 2 mg mL- 1 of the nanoparticles in ethanol) by applying an external magnetic field (~ 1 T). The ZnFe2O4 nanoparticles were applied in an in vitro radiotherapy of lymph node carcinoma of prostate cells (as high...
Paclitaxel molecularly imprinted polymer-PEG-folate nanoparticles for targeting anticancer delivery: Characterization and cellular cytotoxicity
, Article Materials Science and Engineering C ; Volume 62 , 2016 , Pages 626-633 ; 09284931 (ISSN) ; Darvishi, B ; Azizi Ishkuh, F ; Shahmoradi, E ; Mohammadi, A ; Javanbakht, M ; Dinarvand, R ; Atyabi, F ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
The aim of this work was to synthesize molecularly imprinted polymer-poly ethylene glycol-folic acid (MIP-PEG-FA) nanoparticles for use as a controlled release carrier for targeting delivery of paclitaxel (PTX) to cancer cells. MIP nanoparticles were synthesized by a mini-emulsion polymerization technique and then PEG-FA was conjugated to the surface of nanoparticles. Nanoparticles showed high drug loading and encapsulation efficiency, 15.6 ± 0.8 and 100%, respectively. The imprinting efficiency of MIPs was evaluated by binding experiments in human serum. Good selective binding and recognition were found in MIP nanoparticles. In vitro drug release studies showed that MIP-PEG-FA have a...
Fully-coupled mathematical modeling of actomyosin-cytosolic two-phase flow in a highly deformable moving Keratocyte cell
, Article Journal of Biomechanics ; 2017 ; 00219290 (ISSN) ; Firoozabadi, B ; Saidi, M. S ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Interaction between intracellular dynamics and extracellular matrix (ECM) generally occurred into very thin fragment of moving cell, namely lamellipodia, enables all movable cells to crawl on ECM. In fast-moving cells such as fish Keratocytes, Lamellipodia including most cell area finds a fan-like shape during migration, with a variety of aspect ratio function of fish type. In this work, our purpose is to present a novel and more complete two-dimensional continuum mathematical model of actomyosin-cytosolic two-phase flow of a self-deforming Keratocyte with circular spreaded to steady fan-like shape. In the new approach, in addition to the two-phase flow of the F-actin and cytosol, the...
Biodiesel production from Spirulina microalgae feedstock using direct transesterification near supercritical methanol condition
, Article Bioresource Technology ; Volume 239 , 2017 , Pages 378-386 ; 09608524 (ISSN) ; Karimi Sabet, J ; Ghotbi, C ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Microalgae as a candidate for production of biodiesel, possesses a hard cell wall that prevents intracellular lipids leaving out from the cells. Direct or in situ supercritical transesterification has the potential for destruction of microalgae hard cell wall and conversion of extracted lipids to biodiesel that consequently reduces the total energy consumption. Response surface methodology combined with central composite design was applied to investigate process parameters including: Temperature, Time, Methanol-to-dry algae, Hexane-to-dry algae, and Moisture content. Thirty-two experiments were designed and performed in a batch reactor, and biodiesel efficiency between 0.44% and 99.32% was...
A novel technique to extract the maximum power of photovoltaic array in partial shading conditions
, Article International Journal of Electrical Power and Energy Systems ; Volume 101 , 2018 , Pages 500-512 ; 01420615 (ISSN) ; Toulabi, M ; Dobakhshari, A. S ; Taghipour Broujeni, S ; Ranjbar, A. M ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Photovoltaic (PV) arrays are composed of PV cells which have a nonlinear power-voltage characteristic. To extract maximum amount of energy from a PV array, it is essential to track maximum power point (MPP). When all PV cells are subject to the same solar energy, MPP is found easily. However, in some ambient conditions, PV cells are partially or completely shadowed. Under partial shading conditions (PSCs), overall power-voltage curve will have several peaks. This paper presents a novel approach for MPP tracking, utilizing configuration of PV cells in series and parallel that may deliver maximum power in shading conditions. As such, instead of blindly searching for the global MPP among local...
Novel fluoridated silk fibroin/ TiO2 nanocomposite scaffolds for bone tissue engineering
, Article Materials Science and Engineering C ; Volume 82 , 2018 , Pages 265-276 ; 09284931 (ISSN) ; Madaah Hosseini, H. R ; Samadikuchaksaraei, A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
It is known that Fluoride ions strongly affect bone mineralization and formation. In the present study, the engineered bone tissue scaffolds are fabricated using silk fibroin (SF) and flouridated TiO2 nanoparticles. TiO2 nanoparticles are modified by fluoride ions, and different levels (0, 5, 10, 15 and 20 wt%) of the fluoridated TiO2 nanoparticles (TiO2-F) were subsequently added to the SF matrix through phase separation method to prepare silk fibroin/flouridated TiO2 nanocomposite scaffolds (SF/TiO2-F). Phase structure, functional groups, morphology and mechanical properties of the obtained scaffolds were evaluated by X-ray diffraction method (XRD), Fourier transform infrared spectroscopy...
Integrated system of multiple batches to evaluate the continuous performance of microbial cells in decolourization processes
, Article Journal of Environmental Chemical Engineering ; Volume 6, Issue 1 , February , 2018 , Pages 728-735 ; 22133437 (ISSN) ; Bagheri Lotfabad, T ; Heidarinasab, A ; Ebadipour, N ; Yaghmaei, S ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Azo dye degradation in wastewater treatment is a subject which has garnered the attention of many research studies. In this study, an innovative approach, namely, an integrated system of five batches (ISFB), was developed to investigate the capability of Saccharomyces cerevisiae ATCC 9763 for continuous degradation of methyl red as a representative azo dye. Toward this end, an expanded immobilized microbial bed (EIMB) reactor was established with a bed of encapsulated yeast cells in sodium alginate. EIMB reactor was run in two modes, single batch and ISFB. Moreover, durability of the microbial cells was evaluated by repeating the continuous decolourization eight sequential times in EIMB at...