Saravanan Chandran

Investigations on the antiretroviral activity of carbon nanotubes using computational molecular approach.

Carbon nanotubes are the interesting class of materials with wide range of applications. They have excellent physical, chemical and electrical properties. Numerous reports were made on the antiviral activities of carbon nanotubes. However the mechanism of antiviral action is still in infancy. Herein we report, our recent novel findings on the molecular interactions of carbon nanotubes with the three key target proteins of HIV using computational chemistry approach. Armchair, chiral and zigzag CNTs were modeled and used as ligands for the interaction studies. The structure of the key proteins involved in HIV mediated infection namely HIV- Vpr, Nef and Gag proteins were collected from the PDB database. The docking studies were performed to quantify the interaction of the CNT with the three different disease targets. Results showed that the carbon nanotubes had high binding affinity to these proteins which confirms the antagonistic molecular interaction of carbon nanotubes to the disease targets. The modeled armchair carbon nanotubes had the binding affinities of -12.4 Kcal/mole, -20 Kcal/mole and -11.7 Kcal/mole with the Vpr, Nef and Gag proteins of HIV. Chiral CNTs also had the maximum affinity of -16.4 Kcal/mole to Nef. The binding affinity of chiral CNTs to Vpr and Gag was found to be -10.9 Kcal/mole and -10.3 Kcal/mole respectively. The zigzag CNTs had the binding affinity of -11.1 Kcal/mole with Vpr, -18.3 Kcal/mole with Nef and -10.9 with Gag respectively. The strong molecular interactions suggest the efficacy of CNTs for targeting the HIV mediated retroviral infections.

Screening of photosynthetic pigments for herbicidal activity with a new computational molecular approach.

There is an immense interest among the researchers to identify new herbicides which are effective against the herbs without affecting the environment. In this work, photosynthetic pigments are used as the ligands to predict their herbicidal activity. The enzyme 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase is a good target for the herbicides. Homology modeling of the target enzyme is done using Modeler 9.11 and the model is validated. Docking studies were performed with AutoDock Vina algorithm to predict the binding of the natural pigments such as β-carotene, chlorophyll a, chlorophyll b, phycoerythrin and phycocyanin to the target. β-carotene, phycoerythrin and phycocyanin have higher binding energies indicating the herbicidal activity of the pigments. This work reports a procedure to screen herbicides with computational molecular approach. These pigments will serve as potential bioherbicides in the future.

An Approach for Designing an Optimized Reversible Parallel Multiplier by Reversible Gates

In today’s electrical or electronic designing, power dissipation becomes dominant. The promising alternative to these technologies is the reversible computing. Because for irreversible circuits, information is lost and it dissipates energy as heat. The dissipated energy is proportional to the number of bits lost during computation. In case of reversible circuits, they do not dissipate energy in a large amount as irreversible circuits. So information is not lost in reversible circuits during the execution of operation. Thus generation of unique outputs from the particular inputs and reconstruction of inputs from the particular outputs can be achievable. So in the view point of designing issues, reversible logic is a promising field of research that finds applications in low power computing, quantum computing, optical computing and other emerging computing technologies, bioinformatics and nanotechnology-based systems. Here, an approach for the designing of optimized reversible parallel multiplier (ORPM) by reversible gates has been followed. In this regard, this paper represents a new partial reversible gate RPPG for partial product generation for the designing of ORPM. Also, two designing methods are proposed to design ORPM and a comparison is also made between these two methods and the existing reversible multiplier circuits reported in the literature in perspective of the number of reversible gates, constant input, garbage output and total logical calculation.

Comparative study of camshift and KLT algorithms for real time face detection and tracking applications

Face detection and tracking is one of the emerging research areas in the image analysis and computer vision systems. This face detection and tracking helps local security forces to investigate crime incidents. This paper describes a face tracking framework that is capable of tracking a face in real time rapidly frame by frame. Camshift algorithm and KLT algorithm implemented and a comparison study between these two algorithms has been described in this paper. A real time video is experimented using these two algorithms for face detection and tracking. The experimental results show that the KLT algorithm performance is better than the Camshift algorithm in detecting the face and tracking the face. In this article it has been shown how the KLT algorithm proved to be better tracking algorithm than Camshift algorithm.

Analysis of application of arithmetic coding on dct and dct-dwt hybrid transforms of images for compression

The main aim of image compression is to represent the image at minimum amount of bytes. This paper presents a new algorithm that reduces number of bytes required to represent images. The proposed system divides the color image into RGB components, CMY components, YCbCr components separately and DCT and DWT are applied to each component and arithmetic coding is applied to the resultant and then their compression ratios are calculated. The results of DCT based arithmetic encoder and DCT-DWT hybrid arithmetic encoder is compared. It is observed that DCT-DWT hybrid arithmetic encoder approach outperforms DCT-based arithmetic encoder approach. It is also observed that the performance of the DCT-DWT hybrid arithmetic encoder based image compression system is best when the YCbCr components are evaluated. RGB and CMY component based compression provides similar results. This approach is also compared with Colour image compression algorithm based on the DCT transform using difference lookup table.

Offline routing and wavelength assignment for identification of regeneration sites in translucent WDM optical networks

The enormous data carrying capacity and speed of optical WDM networks, have made it an obvious choice for voluminous and high speed data communication. The optical signal can only propagate up to a certain distance (optical reach) retaining its characteristics. Before its quality starts to degrade below a threshold level, it needs to be re-amplified, re-shaped and re-timed using a 3R-regenerator. In this paper, we propose an offline scheme of Routing and Wavelength Assignment (RWA) of connection requests to reduce the number of regeneration sites in a translucent optical network to the extent possible. We compare the performance by of our algorithm with that of an Integer Linear Program (ILP) formulation. We compare the number of regeneration sites computed and channel capacity required for satisfying a given traffic matrix. Performance comparisons show that our algorithm RWA-MRS (RWA to Minimize Regeneration Sites) is able to provide near optimal solution in polynomial time.

An Approach for Designing of Sequence Generator by Counter and Multiplexer of Reversible Gates

In recent years, reversible logic is playing an essential role for getting the satisfied outcome in the digital world of designing, especially where the low power application is needed. In this paper a new reversible gate has been proposed. Furthermore, different types of multiplexer have been designed. Also a positive edge triggered T flip flop has been realized by this proposed gate. Different types of counter also have been implemented here using this T flip flop. Afterwards this paper represents an approach for designing a sequence generator by these counter and multiplexer (SGCAM) of this proposed reversible gate. Sequence generator circuit generates a desired sequence of bits and can be used as a code generator, random bit generator or a prescribed period generator. These types of generator circuits can be used for various type of coding technique particularly required in digital communication.