Government College

About: Government College is a based out in . It is known for research contribution in the topics: Population & Ring (chemistry). The organization has 4481 authors who have published 5986 publications receiving 57398 citations.

Design and analysis of triple notch ultrawideband antenna using single slotted electromagnetic bandgap inspired structure

Abstract: A microstrip line fed pentagonal printed ultra wideband (UWB) monopole antenna with partial ground plane having triple notches is proposed. The realized antenna has an operating bandwidth (VSWR ≤ 2) ranging from 3.1 GHz and continuing beyond 12 GHz. A novel mushroom-shaped slotted electromagnetic bandgap (EBG) inspired structure is used near the feedline to introduce triple notches at CBRS (3.5–3.7) GHz, WLAN (5.15–5.725) GHz and X-band downlink satellite communication (7.25–7.75) GHz frequencies. The band notch characteristics are demonstrated with current distribution and impedance analysis. Further, the proposed structure has stable radiation patterns, gain and group delay in the UWB range except the notch frequencies. Finally, a prototype of the proposed antenna is fabricated and measured results are in good agreement with the simulated results.

Security Challenges in Mobile Ad Hoc Networks - A Survey

Abstract: Mobile Ad-Hoc networks are a kind of temporary networks in which nodes are moving without any fixed infrastructure or centralized administration. Ad collection of nodes that is connected through a wireless medium forming rapidly changing topologies. The infrastructure less and the dynamic nature of these networks demands new set of networking strategies to be implemented in order to provide efficient end-to-end communication. Mobile ad hoc networks (MANETs) represent complex distributed systems that comprise wireless mobile nodes that can freely and dynamically self-organize into arbitrary and temporary network topologies. People and devices are allowed to seamlessly internetwork in areas with no pre communication infrastructure, e.g., disaster recovery environments. Routing in Mobile Ad-Hoc Networks is a challenging task due to its frequent changes in topologies. We discuss in this paper routing protocol, challenges and security of Ad-Hoc networks.

Total Syntheses of the Isomeric Aglain Natural Products Foveoglin A and Perviridisin B: Selective Excited-State Intramolecular Proton-Transfer Photocycloaddition.

Abstract: Selective excited-state intramolecular proton-transfer (ESIPT) photocycloaddition of 3-hydroxyflavones with trans, trans-1,4-diphenyl-1,3-butadiene is described Using this methodology, total syntheses of the natural products (±)-foveoglin A and (±)-perviridisin B were accomplished Enantioselective ESIPT photocycloaddition using TADDOLs as chiral hydrogen-bonding additives provided access to (+)-foveoglin A Mechanistic studies have revealed the possibility for a photoinduced electron-transfer (PET) pathway

Numerical simulation for fractional Jaulent–Miodek equation associated with energy-dependent Schrödinger potential using two novel techniques

Abstract: In present work, we investigate the numerical solution of time-fractional Jaulent–Miodek (JM) equations with the aid of two novel techniques namely, coupled fractional reduced differential transfor...

Niacin-mediated Gene Expression and Role of NiaR as a Transcriptional Repressor of niaX, nadC, and pnuC in Streptococcus pneumoniae.

Abstract: NAD (Nicotinamide Adenine Dinucleotide) biosynthesis is vital for bacterial physiology and plays an important role in cellular metabolism. A naturally occurring vitamin B complex, niacin (nicotinic acid), is a precursor of coenzymes NAD and NADP. Here, we study the impact of niacin on global gene expression of Streptococcus pneumoniae D39 and elucidate the role of NiaR as a transcriptional regulator of niaX, nadC, and pnuC. Transcriptome comparison of the D39 wild-type grown in chemically defined medium (CDM) with 0 to 10 mM niacin revealed elevated expression of various genes, including niaX, nadC, pnuC, fba, rex, gapN, pncB, gap, adhE, and adhB2 that are putatively involved in the transport and utilization of niacin. Niacin-dependent expression of these genes is confirmed by promoter lacZ-fusion studies. Moreover, the role of transcriptional regulator NiaR in the regulation of these genes is explored by DNA microarray analysis. Our transcriptomic comparison of D39 ΔniaR to D39 wild-type revealed that the transcriptional regulator NiaR acts as a transcriptional repressor of niaX, pnuC, and nadC. NiaR-dependent regulation of niaX, nadC, and pnuC is further confirmed by promoter lacZ-fusion studies. The putative operator site of NiaR (5'-TACWRGTGTMTWKACASYTRWAW-3') in the promoter regions of niaX, nadC, and pnuC is predicted and further confirmed by promoter mutational experiments.