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Shobana S.,Rajas International Institute of Technology for Women
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2014

Coordinating behavior of novel N2O type mixed ligand complexes (1-6) have been synthesized from substituted fluoropyrimidine [5-Fluorouracil (5-FU; A)] with biopotent imidazole enzyme constituents (B) viz., imidazole(him) and benzimidazole(bim) in the presence of Ni(II), Cu(II) and Zn(II) ions. Synthesized complexes were characterized by chemical analysis, spectral studies, magnetic moment and conductivity measurements. The results of chemical analysis and the observed low molar conductance values propose their stoichiometry to be 1:1:1 (M:A:B) with non-electrolytic nature. From the spectral data, it is inferred that the ligands A & B coordinate with M(II) ions in bi and monodentate approach through C(4)O, N(3) and imidazole ring N(3) atoms respectively. The thermogravimetric analysis shows the dehydration, decomposition and thermal stability of mixed ligand complexes. XRD and SEM patterns show sharp crystalline peaks with homogeneous morphology. In vitro antimicrobial activities of free ligands (A & B) and their metal complexes were screened against some pathogenic strains by well diffusion technique. Absorption and gel electrophoresis experiments on the interaction of mixed ligand complexes with DNA suggest that all the complexes can bind as well as cleave the DNA by intercalation between chromophores and DNA base pairs. In addition, in vitro antioxidant activities were tested by DPPH free radical scavenging model. © 2014 Elsevier B.V. All rights reserved.


Shobana S.,Rajas International Institute of Technology for Women | Mitu L.,University of Pitesti
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2015

Some biologically active mixed ligand complexes (1-9) have been synthesized from 5-Fluorouracil (5-FU; A) and amino acids (B) such as glycine (gly), l-alanine (ala) and l-valine (val) with Ni(II), Cu(II) and Zn(II) ions. The synthesized mixed ligand complexes (1-9) were characterized by various physico-chemical, spectral, thermal and morphological studies. 5-Fluorouracil and its mixed ligand complexes have been tested for their in vitro biological activities against some pathogenic bacterial and fungal species by the agar well diffusion method. The in vitro antioxidant activities of 5-Fluorouracil and its complexes have also been investigated by using the DPPH assay method. The results demonstrate that Cu(II) mixed ligand complexes (4-6) exhibit potent biological as well as antioxidant activities compared to 5-Fluorouracil and Ni(II) (1-3) and Zn(II) (7-9) mixed ligand complexes. Further, the cleaving activities of CT DNA under aerobic conditions show moderate activity with the synthesized Cu(II) and Ni(II) mixed ligand complexes (1-6) while no activity is seen with Zn(II) complexes (7-9). Binding studies of CT DNA with these complexes show a decrease in intensity of the charge transfer band to the extent of 5-15% along with a minor red shift. The free energy change values (Δ‡G) calculated from intrinsic binding constants indicate that the interaction between mixed ligand complex and DNA is spontaneous. © 2014 Elsevier B.V. All rights reserved.


Joselin Retna Kumar G.,Sathyabama University | Shaji K.S.,Rajas International Institute of Technology for Women
Journal of Computer Science | Year: 2014

This study proposes an efficient channel-estimation scheme for Multiband (MB) Orthogonal Frequency Division Multiplexing (OFDM)-based Ultra Wide Band (UWB) communication systems. One of the challenges in wireless system is the frequency selective fading caused due to multipath channel between the transmitter and receiver. The signal bandwidth in broad band cellular wireless systems typically exceeds the coherence bandwidth of the multipath channel. To overcome such a multipath fading environment with low complexity and to increase the performance, UWB OFDM system is used. To practically realize MB-OFDM UWB, one needs to cope with numerous design challenges, particularly in receiver designs such as symbol timing, Carrier Frequency Offset (CFO) and sampling frequency offset compensation, as well as Channel Frequency Response (CFR) estimation. A channel estimation scheme using a Takagi-Sugeno (T-S) fuzzy based neural network under the time varying velocity of the mobile station in a UWB OFDM system is proposed in this study. In our proposal, by utilizing the learning capability of Adaptive Neuro-Fuzzy Inference System (ANFIS), the ANFIS is trained with correct channel state information then the trained network is used as a channel estimator. To validate the performance of our proposed method, simulation results are given and found that it gives more accurate prediction of channel coefficients as compared with fuzzy channel estimator under various highly noisy multipath channel conditions. © 2014 Science Publications.


Premi M.S.G.,Sathyabama University | Shaji K.S.,Rajas International Institute of Technology for Women
2nd International Conference on Communication Software and Networks, ICCSN 2010 | Year: 2010

In recent days the advancement in the wireless communication is with that of wireless sensor networks. In Wireless Sensor Networks (WSNs) the data are collected from many sensor nodes by the base station which is the goal of the network. In this type of WSNs, the major constraints are low energy, limited bandwidth and less memory. With these constraints in mind we propose a method to reduce the energy consumption with maximum data collection. In this new method we use multiple mobile sinks (MMS) instead of a single mobile sink. Here we have considered three scenarios. In the first scenario, all nodes are interested to send data to only one sink. In the second and third scenario all nodes are interested to send the data to any other mobile sink among the selected group of mobile sinks. We have simulated using MATLAB and the simulated results show that the update energy cost is reduced when two or more number of sinks are used. © 2010 IEEE.


Prabakaran N.,Sathyabama University | Shaji K.S.,Rajas International Institute of Technology for Women
International Conference on Signal Processing, Image Processing and Pattern Recognition 2013, ICSIPR 2013 | Year: 2013

In this paper, we analyze the error rate performance (BER & PER) of uplink coded 2×2 multiple-input multiple-output orthogonal frequency division multiple access (MIMO OFDMA) systems under AWGN fading channel conditions. The IEEE 802.16 standard, commonly known as WiMAX, is the latest technology that has promised to offer broadband wireless access over long distance. Since 2001 WiMAX has evolved from 802.16 to 802.16d for fixed wireless access and to the new IEEE 802.16e standard with mobility support. In WiMAX, multiple input multiple-output (MIMO) antenna technologies play an essential role in meeting the 4G requirements. The application of MIMO technologies is one of the most crucial distinctions between 3G and 4G. A large family of MIMO techniques has been developed for various links and with various amounts of available channel state information in IEEE 802.16e/m. In this paper, the performance of uplink STC (Space Time Coding) PUSC with Matrix B under ITU OIP-B outdoor-to-indoor pedestrian channels with the velocity of 3Km/h for various subcarrier modulation systems. The outputs have been generated averaging over 1000 frames on MIMO channel. © 2013 IEEE.


Godwin Premi M.S.,Sathyabama University | Shaji K.S.,Rajas International Institute of Technology for Women
European Journal of Scientific Research | Year: 2012

In all the fields of communication, network security is taken into consideration whenever the data needs protection, authentication and confidentiality. To avoid fraudulent access and unauthorized hearing or inclusion many encryption and authentication methods are proposed. Here we proposed a simple symmetric ciphering with authentication (SSCA) algorithm to secure the routing information and to verify the authenticity of the node. Once the route is protected and nodes' authenticity is verified then automatically the path for the inclusion of unauthorized data will be closed. We employed this new approach in the multiple mobile sinks (MMS) routing for large wireless sensor networks. We have simulated using MATLAB and from the simulated results we show that the unauthorized data inclusion is avoided with the low energy spent. © 2012 EuroJournals Publishing, Inc.


Ganesan V.,Sathyabama University | Shaji K.S.,Rajas International Institute of Technology for Women
Proceedings of the IEEE International Caracas Conference on Devices, Circuits and Systems, ICCDCS | Year: 2014

This paper enumerates the design of high speed Positive & Negative edge triggered D flip flops using AlGaAs/GaAs MODFET. This Flip Flops having less number of transistors. It can be efficiently used in VLSI ICs. The verification is done using simulation the proposed Flip Flops appear to have better speed of operation. It is simple and suitable to SPICE simulation of hybrid digital ICs. © 2014 IEEE.


Jeya Shobana S.,Rajas International Institute of Technology for Women | Paramasivan B.,National Engineering College
International Journal of Multimedia and Ubiquitous Engineering | Year: 2015

Congestion in Wireless Sensor Networks (WSN) get worse when there are multiple and random flows of data in which some have superior significance over the others requiring fidelity in terms of packet delivery, QoS, energy efficiency and throughput. In node-level, congestion leads to impairment of packets that obviously reduces the QoS. In this paper, we present a Cluster based congestion control with Rate Adjustment based on Priority (CRAP) protocol, which self-organizes the sensor nodes into clusters. These clusters monitor congestion in a proactive manner within its confined range which exchanges information among them and adjusts the traffic rate when one cluster has high priority flow over the other. This rate adjustment is based on the exchange of traffic rate estimate among the clusters that reduces packet re-transmissions and energy loss. Our simulation expedites system wide rate control resulting in good throughput, very low packet loss probability and delay that deals with multiple, random flows of data. © 2015 SERSC.


Jeya Shobana S.,Rajas International Institute of Technology for Women | Paramasivan B.,National Engineering College
International Journal of Communication Networks and Information Security | Year: 2015

Wireless Sensor Networks (WSNs) have been a current trend in the research field and has many issues when there are multiple mobile sinks. Data dissemination gets critical as their locations have to be repeatedly updated and results in huge consumption of the restricted battery supply in sensor nodes. In this paper, we propose GCCP - NS, a grid based congestion control protocol with N-sinks that solves the data dissemination problem leading to congestion. We construct a dual level grid structure to trail the locations of all the source nodes that reports the information to the mobile sinks by monitoring the network in a hierarchical manner. As an added advantage, it aids in data dissemination based on query flooding from the mobile sinks using quorum based method within each cell in the grid and avoids congestion in an effective manner. Simulation results show that our proposed protocol outperforms the other schemes in terms of packet delivery ratio, energy expenditure and throughput.


Jeyalakshmi Kala K.L.,Rajas International Institute of Technology for Women | Chandran M.,Vivekananda College
International Journal of Pharma and Bio Sciences | Year: 2014

Crabs are a good source of protein, carbohydrates and various minerals. Therefore, determining of the proximate and mineral elements of crab species has a great importance due to the good effect on human health. In the present study proximate and minerals composition of the crabs collected from the marine, estuarine, freshwater and terrestrial environments were analysed. The study reveals the higher protein content was observed in the marine crabs Portunus pelagicus (23.23±0.22) and lowest protein level (13.23±0.02) was recorded in Cardisoma carnifex crabs. In the body meat minimum carbohydrate content (1.1±0.02%) was recorded in Barytelphusa cunicularis crabs and maximum (1.32±0.01%) value were recorded in the land crab C. carnifex. Particularly, marine and estuarine crabs posses higher protein content than the land and fresh water crabs. However, the findings of minerals of calcium, magnesium, sodium and potassium composition of estuarine and marine crabs particularly is more but the content of iron and copper content was high fresh water and terrestrial crab species. It can then be inferred that the crabs could be employed as a supplement of protein and mineral matter so as to balance human nutrition. Hence the consumption of marine crabs would help to prevent nutritional deficiencies in the future. It could be safely presumed that P. pelagicus is a good source of protein and recommended as an ideal food item.

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