Shiv Nadar University

About: Shiv Nadar University is a education organization based out in Dadri, Uttar Pradesh, India. It is known for research contribution in the topics: Population & Graphene. The organization has 1015 authors who have published 1924 publications receiving 18420 citations.

A manual of diseases of tropical acacias in Australia, South-East Asia and India

Abstract: This manual provides methods for the development and evaluation of criteria and indicators (C&I) which can then be used to assess the sustainability of forest management. The manual is written primarily for researchers, people or groups interested in evaluating C&I for assessments of forests in new areas, or as a reference for readers wanting to know how CIFOR's Generic Template was produced. The methods presented are aimed at the development of sets of C&I for natural forest at the forest management unit level, especially in the tropics. Following an introductory chapter focusing on the overall purpose, specific objectives, and the C&I development process, three chapters explain how to prepare for C&I testing, how to conduct a test, and how to analyse the results. Subsequent chapters explain the conceptual basis of C&I development, with three case studies offered as examples, and suggested additional reading materials. Specific forms and tools that have been used in the course of CIFOR's testing are also presented, with examples of ways to present the results. The final chapter provides possible baseline sets of C&I, available to users for evaluation and testing in their own contexts.

Graphene Oxide-Coated Surface: Inhibition of Bacterial Biofilm Formation due to Specific Surface–Interface Interactions

Abstract: Graphene oxide (GO) is a promising and remarkable nanomaterial that exhibits antimicrobial activity due to its specific surface–interface interactions. In the present work, for the first time, we have reported the antibacterial activity of GO-coated surfaces prepared by two different methods (Hummers’ and improved, i.e., GOH and GOI) against bacterial biofilm formation. The bacterial toxicity of the deposited GO-coated surfaces was investigated for both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) models of bacteria. The mechanism of inhibition is different on the coated surface than that in suspension, as determined by measurement of the percentage inhibition of biofilm formation, Ellman’s assay, and colony forming unit (CFU) studies. The difference in the nature, degree of oxidative functionalities, and size of the synthesized GO nanoparticles mitigates biofilm formation. To better understand the antimicrobial mechanism of GO when coated on surfaces, we were able to demonst...

Cardanol benzoxazines – interplay of oxazine functionality (mono to tetra) and properties

Abstract: Cardanol, a sustainable origin phenol, was utilized as a reactive diluent to mediate solventless Mannich-type condensation reaction with para-formaldehyde and primary aromatic amines to form a homologous series of benzoxazine (Bz) monomers namely C-a, C-ddm, C-trisapm and C-tetraapm which differ in their degree of oxazine functionality as mono-, di-, tri- and tetra-oxazine respectively. A strong correlation is reflected between the number of oxazine rings in the monomer and the polymerization behavior, thermo-mechanical transitions, and properties of the polybenzoxazine synthesized. The monomer structure was confirmed by FTIR, 1H-, 13C-NMR spectroscopy and mass spectrometry. The curing, rheological, thermo-mechanical and thermal properties were determined using DSC, FTIR, rheometer, DMTA, LSS and TGA studies. The curing characteristic due to ROP of Bz monomers was supported both by DSC and FTIR studies. The presence of neighboring oxazine group in monomers (C-a to C-tetraapm) strongly attenuates the curing temperature (Ti = 225–140 °C), enhances Tg, thermal stability, and mechanical properties. Interestingly, DFT calculations also supported the lowest curing temperature for highest oxazine functionality monomer (C-tetraapm). The interplay between the degree of oxazine functionality in the monomer; extent of H-bonding and crosslink density values in sustainable origin synthesized polybenzoxazines is suggested. The thermoset showed an increasing trend (PC-a < PC-ddm < PC-trisapm < PC-tetraapm) in Tg (58–109 °C), thermal stability (355–391 °C), char yield (13–37%), LOI (23–31) and storage modulus (3.6–66.5 MPa) values. The monomers are liquid to semi-viscous paste at room temperature and showed potential for solventless processing in adhesive applications.

Fully Dynamic Maximal Matching in O (log n) Update Time

Abstract: We present an algorithm for maintaining maximal matching in a graph under addition and deletion of edges. Our data structure is randomized that takes $O( \log n)$ expected amortized time for each edge update where $n$ is the number of vertices in the graph. While there is a trivial $O(n)$ algorithm for edge update, the previous best known result for this problem was due to Ivkovi\'c and Llyod\cite{llyod}. For a graph with $n$ vertices and $m$ edges, they give an $O( {(n+ m)}^{0.7072})$ update time algorithm which is sub linear only for a sparse graph. %To the best of our knowledge this %is the first polylog update time for maximal matching that implies an % exponential improvement from the previous results. For the related problem of maximum matching, Onak and Rubinfeld \cite{onak} designed a randomized data structure that achieves $O(\log^2 n)$ expected amortized time for each update for maintaining a $c$-approximate maximum matching for some large constant $c$. In contrast, we can maintain a factor two approximate maximum matching in $O(\log n )$ expected amortized time per update as a direct corollary of the maximal matching scheme. This in turn also implies a two approximate vertex cover maintenance scheme that takes $O(\log n )$expected amortized time per update.