An adaptive approach for information dissemination in Vehicular Ad hoc Networks

Vehicular Ad hoc Networks (VANETs) appeared as a subclass of MANETs for inter-vehicle communication. However, VANETs have a relatively more dynamic nature as compared to MANETs concerning the network topology. The design and implementation of an efficient and scalable algorithm for information dissemination in VANETs constitutes a major issue that should be tackled. Indeed, in this dynamic environment, an increasing number of redundant broadcast messages will increase resource utilization, which would indirectly affect the network performance. In the past few years, several statistical-based broadcasting schemes, such as counter-based protocol, for information dissemination have been proposed in the context of MANETs. These schemes are based on various threshold parameters to help nodes to decide whether to rebroadcast or discard received messages. However, in dynamic networks, such as in VANETs, it is difficult even impossible to determine a priori these threshold values. Dynamically changing these values, to minimize the number of redundantly received messages while maintaining good latency and reachability, is a complex issue in the absence of centralized controllers or constant threshold parameters. This paper presents a decentralized and adaptive approach for information dissemination (AID) in VANETs. Simulations are conducted and results are presented to show that adaptive approaches have a better performance over statistical-based approaches.     

Green Nanoarchitectonics of Cu/Fe3O4 Nanoparticles Using Helleborus niger Extract Towards an Efficient Nanocatalyst,Antioxidant and Anti-lung Cancer Agent

Biogenic nanoarchitectured magnetic materials have drawn serious attention throughout the last decade. We have attempted the Helleborus niger flower extract functionalized and templated biogenic synthesis of Cu nanoparticles supported Fe₃O₄ as a likewise novel material. The plant phytomolecules were deployed as a non-toxic sustainable reductant and an outstanding capping agent to stabilize the synthesized NPs. The synthesized Cu/H.niger@Fe₃O₄ nanocomposite was undergone comprehensive characterizations through Fourier transformed infrared spectroscopy (FT-IR), electron microscopy (SEM and TEM), energy dispersive X-ray spectroscopy (EDX), elemental mapping, vibrating sample magnetometer (VSM), X-ray diffraction (XRD) and inductively coupled plasma (ICP) techniques. The material was catalytically explored in the synthesis of diverse pyrano[3,2-c]chromene derivatives by coupling 4-hydroxycoumarin, malononitrile and a range of aldehydes in hot water when it afforded excellent yields. Based on its core magnetism, the catalyst was easily recovered using a magnet and reused for 8 successive times without considerable loss in catalytic activity. After the chemical application, the synthesized Cu/H.niger@Fe₃O₄ nanocomposite was engaged in biological assays like study of anti-oxidant properties by DPPH mediated free radical scavenging test using BHT as a reference molecule. Thereafter, on having a significant IC₅₀ value in radical scavenging assay, we extended the bio-application of the desired nanocomposite in anticancer study of A549 and H358 human lung cell lines in-vitro through MTT assay. The cell viability of malignant lung cell line reduced dose-dependently in the presence of desired nanocomposite. So, these results suggest that synthesized Cu/H.niger@Fe₃O₄ as a chemotherapeutic nanomaterial have a suitable anticancer activity against lung cell lines.

     

Synthesis and Characterization of Some Complexes Derived from Isatin Dye Ligand and Study of their Biological Potency and Anticorrosive Behavior on Aluminum Metal in Acidic Medium

Divalent Mn, Ni, Zn, and trivalent La complexes of H₃L ligand [N’,2-bis((Z)-2-oxoindolin-3-ylidene)hydrazine-1 carbohydrazide] were synthesized and characterized via diverse spectroscopic methods (FT-IR, NMR, electronic, PXRD, and GC-MS), molar conductance and magnetic susceptibility measurements. The different ways of binding for the H₃L ligand with metal ions were inferred, as the H₃L ligand acted in mono-negative N²O tridentate, mono-negative N²O³ pentadentate, bi-negative N²O³ pentadentate, and tri-negative N²O³ pentadentate manners in coordination to Mn²⁺, Zn²⁺, La³⁺, and Ni²⁺ metal ions, respectively. DFT modeling was performed using the DMOL³/material studio software, and some of the experimental outcomes were interpreted and authenticated. Electrochemical performance of Mn²⁺ ions in the existence and absence of H₃L ligand was considered via cyclic voltammetry. The corrosion effectiveness of the H₃L ligand (inhibitor) to aluminum metal was evaluated, and the molecular dynamic (MD) simulations for adsorption of the H₃L inhibitor on Al surface were performed via FORCITE quench code. The isolated compounds were inspected for their antimicrobial (against C. albicans fungi, G⁺ bacteria S. aureus and B. subtilis, and G^? bacteria P. aeruginosa and E. coli), cytotoxic, and antioxidant (ABTS, and SOD) activities. A molecular docking study was performed to give the favorable binding sites for the ligand to E. coli, and S. aureus proteins.