scispace - formally typeset
Search or ask a question
Author

Rajendiran Rajesh

Other affiliations: VIT University
Bio: Rajendiran Rajesh is an academic researcher from National Chung Cheng University. The author has contributed to research in topics: Catalysis & Tissue engineering. The author has an hindex of 15, co-authored 70 publications receiving 658 citations. Previous affiliations of Rajendiran Rajesh include VIT University.


Papers
More filters
01 Jan 2009
TL;DR: It is suggested that AODV routing protocol can be used under high mobility since it outperforms DSDV, TORA and DSR protocols.
Abstract: ††† Summary Ad Hoc Networks are multi - hop wireless networks with dynamically changing network connectivity owing to mobility. The protocol suite includes several routing protocols specifically designed for ad-hoc routing. The conventional routing protocols such as shortest-path routing algorithms are not particularly well suited for operation in ad-hoc networking environment. The most widely used ad hoc routing protocols are Ad-hoc On-Demand Distance Vector Routing (AODV), Destination Sequenced Distance Vector (DSDV), Dynamic Source Routing (DSR) and Temporally - Ordered Routing Algorithm (TORA). In this paper, the three random based mobility models such as Random waypoint, Random walk and Random Directions were implemented. The two different parameter constraints like packet-delivery fraction and End-toend packet delivery delay are compared with respect to mobility speed, Traffic and Network size. The simulation results shows that the AODV protocols in Random Waypoint mobility model performs better than DSDV, TORA and DSR in Random walk and random Direction mobility model. . Based on the observations, it is to suggest that AODV routing protocol can be used under high mobility since it outperforms DSDV, TORA and DSR protocols.

105 citations

Journal ArticleDOI
TL;DR: In this paper, the isolated HAP has been characterized using thermo gravimetric analysis (TG) and differential thermal analysis (DTA), Fourier Transformed Infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission electron microscope (FE-SEM), and energy dispersive x-ray (EDX).
Abstract: Natural hydroxyapatite (HAP) is isolated from waste chicken bone by thermal calcinations at different temperatures in the range of 200 °C to 1000 °C. The isolated HAP has been characterized using thermo gravimetric analysis (TG) and differential thermal analysis (DTA), Fourier Transformed Infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission electron microscope (FE-SEM), and energy dispersive X-ray (EDX). The XRD results showed that the enhanced crystallinity of HAP phase by thermal calcination above 600 °C and the crystal size has been found to increase with increasing temperature of thermal calcinations due to agglomeration. Value addition for the waste chicken bone is given by the isolation of useful bioceramics (HAP) and the optimum temperature for the thermal calcination is found to be 600 °C. The isolated HAP has been characterized as carbonated HAP of B type with the hexagonal structure. These results will not only make the chicken bone as an important bioresource for the HAP but wi...

64 citations

Journal ArticleDOI
TL;DR: Results indicate that this tricomponent scaffold with an oxidized multiwalled carbon nanotube (fMWCNT)–alginate–hydroxyapatite with the required porosity could be a promising candidate for bone tissue engineering.
Abstract: In recent times, tricomponent scaffolds prepared from naturally occurring polysaccharides, hydroxyapatite, and reinforcing materials have been gaining increased attention in the field of bone tissue engineering. In the current work, a tricomponent scaffold with an oxidized multiwalled carbon nanotube (fMWCNT)-alginate-hydroxyapatite with the required porosity was prepared for the first time by a freeze-drying method and characterized using analytical techniques. The hydroxyapatite for the scaffold was isolated from chicken bones by thermal calcination at 800°C. The Fourier transform infrared spectra and X-ray diffraction data confirmed ionic interactions and formation of the fMWCNT-alginate-hydroxyapatite scaffold. Interconnected porosity with a pore size of 130-170 µm was evident from field emission scanning electron microscopy. The total porosity calculated using the liquid displacement method was found to be 93.85%. In vitro biocompatibility and cell proliferation on the scaffold was checked using an MG-63 cell line by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and cell attachment by Hoechst stain assay. In vitro studies showed better cell proliferation, cell differentiation, and cell attachment on the prepared scaffold. These results indicate that this scaffold could be a promising candidate for bone tissue engineering.

45 citations

Journal ArticleDOI
TL;DR: Experimental results revealed that CRM197-ApoE-RA-PAAM-CH-PLGA NPs can be a promising formulation to deliver RA to Aβ-insulted neurons in the pharmacotherapy of Alzheimer's disease.

39 citations

Journal ArticleDOI
TL;DR: The prepared tricomponent scaffolds could be used as promising biomaterials in tissue engineering and exhibited higher biocompatibility, mineralization and cell attachment.
Abstract: Regenerative medicine witnessed a paradigm shift from synthetic implants and tissue grafts to a tissue engineering approach that incorporates biodegradable, bioceramic composite scaffolds with biological cells. A combination of carbon nanomaterials and hydroxyapatite (HAP) with polysaccharides holds a great potential in bone tissue engineering. In the present study, new porous tricomponent scaffolds, graphene oxide (GO)–gellan–HAP, GO–alginate–HAP and GO–amylopectin–HAP were prepared by freeze drying method. The ionic interactions between the individual components in the formation of the composites were confirmed by FTIR and XRD. The porous morphology of scaffolds was confirmed by FE-SEM images. Osteoconductivity and biocompatibility of scaffolds on MG 63 cell line were confirmed by in vitro MTT assay. The increased mineralization could be visualized by alkaline phosphatase (ALP) activity. Among the scaffolds, the GO–amylopectin–HAP exhibited higher biocompatibility, mineralization and cell attachment. The compressive strength values were determined and found to be 466.8 ± 19 for GO–gellan–HAP, 171 ± 17 for GO–alginate–HAP and 161 ± 4 for GO–amylopectin–HAP scaffolds. The higher biocompatibility, mineralization and cell attachment and lower compressive strength for GO–amylopectin–HAP was attributed to higher pore size and porosity. These results indicated that the prepared tricomponent scaffolds could be used as promising biomaterials in tissue engineering.

39 citations


Cited by
More filters
13 Jul 2017
TL;DR: It is demonstrated that cryo-EM allows atomic characterization of amyloid filaments from patient-derived material, and pave the way for investigation of a range of neurodegenerative diseases.
Abstract: Alzheimer’s disease is the most common neurodegenerative disease, and there are no mechanism-based therapies. The disease is defined by the presence of abundant neurofibrillary lesions and neuritic plaques in the cerebral cortex. Neurofibrillary lesions comprise paired helical and straight tau filaments, whereas tau filaments with different morphologies characterize other neurodegenerative diseases. No high-resolution structures of tau filaments are available. Here we present cryo-electron microscopy (cryo-EM) maps at 3.4–3.5 A resolution and corresponding atomic models of paired helical and straight filaments from the brain of an individual with Alzheimer’s disease. Filament cores are made of two identical protofilaments comprising residues 306–378 of tau protein, which adopt a combined cross-β/β-helix structure and define the seed for tau aggregation. Paired helical and straight filaments differ in their inter-protofilament packing, showing that they are ultrastructural polymorphs. These findings demonstrate that cryo-EM allows atomic characterization of amyloid filaments from patient-derived material, and pave the way for investigation of a range of neurodegenerative diseases. High-resolution structures of tau filaments shed light on the ultrastructure of neurofibrillary lesions in Alzheimer’s disease. Alzheimer's disease is defined by the presence of abundant neurofibrillary lesions and neuritic plaques in the cerebral cortex. The lesions are made of paired helical and straight tau filaments (PHFs and SFs, respectively). Different tau filaments characterize other neurodegenerative diseases, suggesting that molecular conformers of aggregated tau underlie human tauopathies. No high-resolution structures of tau filaments are currently available. Here, Sjors Scheres and colleagues present cryo-electron microscopy (cryo-EM) maps at 3.5 A resolution and corresponding atomic models of PHFs and SFs from the brain of an individual with Alzheimer's disease. Their results show that cryo-EM enables atomic characterization of amyloid filaments from patient-derived material and could be used to study a range of neurodegenerative diseases.

652 citations

01 Aug 2010
TL;DR: These analyses show that optimal hES cell substrates are generated from monomers with high acrylate content, have a moderate wettability, and employ integrin αvβ3 and αv β5 engagement with adsorbed vitronectin to promote colony formation.
Abstract: Structure–property relationships between material properties and stem cell behaviour are investigated using high-throughput methods. The data identify the optimal substrates within a range of different polymeric surfaces to support the growth and self-renewal of human embryonic stem cells from fully dissociated single cells.

468 citations

Journal ArticleDOI
TL;DR: This review elucidate FGNs-bioorganism interactions and summarize recent advancements on designing FGN-based two-dimensional and three-dimensional architectures as multifunctional biological platforms.
Abstract: Functional graphene nanomaterials (FGNs) are fast emerging materials with extremely unique physical and chemical properties and physiological ability to interfere and/or interact with bioorganisms; as a result, FGNs present manifold possibilities for diverse biological applications. Beyond their use in drug/gene delivery, phototherapy, and bioimaging, recent studies have revealed that FGNs can significantly promote interfacial biointeractions, in particular, with proteins, mammalian cells/stem cells, and microbials. FGNs can adsorb and concentrate nutrition factors including proteins from physiological media. This accelerates the formation of extracellular matrix, which eventually promotes cell colonization by providing a more beneficial microenvironment for cell adhesion and growth. Furthermore, FGNs can also interact with cocultured cells by physical or chemical stimulation, which significantly mediate their cellular signaling and biological performance. In this review, we elucidate FGNs–bioorganism int...

405 citations

24 Feb 2007
TL;DR: In this article, the synthesis and detailed characterization of graphite thin films produced by thermal decomposition of the (0001) face of a 6H-SiC wafer, demonstrating the successful growth of single crystalline films down to approximately one graphene layer.
Abstract: This paper reports the synthesis and detailed characterization of graphite thin films produced by thermal decomposition of the (0001) face of a 6H-SiC wafer, demonstrating the successful growth of single crystalline films down to approximately one graphene layer. The growth and characterization were carried out in ultrahigh vacuum (UHV) conditions. The growth process and sample quality were monitored by low-energy electron diffraction, and the thickness of the sample was determined by core level x-ray photoelectron spectroscopy. High-resolution angle-resolved photoemission spectroscopy shows constant energy map patterns, which are very sharp and fully momentum-resolved, but nonetheless not resolution limited. We discuss the implications of this observation in connection with scanning electron microscopy data, as well as with previous studies.

345 citations

Journal ArticleDOI
TL;DR: This paper surveys the various ICIC avoidance schemes in the downlink of OFDMA-based cellular networks and introduces new parameterized classifications and makes use of these classifications to categorize and review various static and dynamic ICIC schemes.
Abstract: Orthogonal Frequency Division Multiplexing Access (OFDMA) has been increasingly deployed in various emerging and evolving cellular systems to reduce interference and improve overall system performance. However, in these systems Inter-Cell Interference (ICI) still poses a real challenge that limits the system performance, especially for users located at the cell edge. Inter-cell interference coordination (ICIC) has been investigated as an approach to alleviate the impact of interference and improve performance in OFDMA-based systems. A common ICIC technique is interference avoidance in which the allocation of the various system resources (e.g., time, frequency, and power) to users is controlled to ensure that the ICI remains within acceptable limits. This paper surveys the various ICIC avoidance schemes in the downlink of OFDMA-based cellular networks. In particular, the paper introduces new parameterized classifications and makes use of these classifications to categorize and review various static (frequency reuse-based) and dynamic (cell coordination-based) ICIC schemes.

339 citations