Avinash C. Pandey

Bio: Avinash C. Pandey is an academic researcher from Allahabad University. The author has contributed to research in topics: Photoluminescence & Nanoparticle. The author has an hindex of 45, co-authored 301 publications receiving 7576 citations. Previous affiliations of Avinash C. Pandey include Jaypee Institute of Information Technology & Indian Council of Agricultural Research.

Nitric Oxide Ameliorates Zinc Oxide Nanoparticles Phytotoxicity in Wheat Seedlings: Implication of the Ascorbate-Glutathione Cycle.

Abstract: The present study investigates ameliorative effect of nitric oxide (NO) against zinc oxide nanoparticles (ZnONPs) phytotoxicity in wheat seedlings. ZnONPs exposure hampered growth of wheat seedlings which was coincided with reduced photosynthetic efficiency (Fv/Fm and qP) due to increased accumulation of zinc (Zn) in xylem and phloem saps. However, SNP supplementation has partially mitigated the ZnONPs-mediated toxicity by modulation of photosynthetic activity and Zn accumulation in xylem and phloem sap. Further, the results reveal that ZnONPs treatments enhanced level of hydrogen peroxide (H2O2) and hence lipid peroxidation (as malondialdehyde; MDA) due to severely inhibited activities of the ascorbate-glutatione cycle (AsA-GSH) enzymes: ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR) and dehydroascorbate reductase (DHAR), and its associated metabolites: reduced ascorbate and glutathione. In contrast to this, the addition of SNP together with ZnONPs maintained the cellular functioning of the AsA-GSH cycle properly, hence lesser damage was noticed in comparison to ZnONPs treatments alone. The protective effect of SNP against ZnONPs toxicity on fresh weight (growth) can be reversed by 2-(4carboxy-2-phenyl)-4,4,5,5-tetramethyl- imidazoline-1-oxyl-3-oxide, a NO scavenger, suggesting role of NO released from SNP in ameliorating ZnONPs toxicity. Overall the results of the present study have shown about implication of NO in the reducing ZnONPs toxicity through the regulation of accumulation of Zn, and functioning of the AsA-GSH cycle.

Parthenium leaf extract mediated synthesis of silver nanoparticles: a novel approach towards weed utilization

Abstract: In this paper we describe the synthesis of silver nanoparticles using Parthenium leaf extract. Transmission electron microscopy analysis of these particles shows that they are ~ 50 nm in range and assembled in very irregular shape of variable morphology. The most needed outcome of this work will be the development of value-added products from Parthenium for biomedical and nanotechnology based industries.

Twitter sentiment analysis using hybrid cuckoo search method

Abstract: A hybrid cuckoo search method (CSK) has been presented for Twitter sentiment analysis.CSK modifies the random initialization of population in cuckoo search (CS) by K-means to resolve the problem of random initialization.The proposed algorithm has outperformed five popular algorithms.The statistical analysis has been done to validate the performance of the proposed algorithm. Sentiment analysis is one of the prominent fields of data mining that deals with the identification and analysis of sentimental contents generally available at social media. Twitter is one of such social medias used by many users about some topics in the form of tweets. These tweets can be analyzed to find the viewpoints and sentiments of the users by using clustering-based methods. However, due to the subjective nature of the Twitter datasets, metaheuristic-based clustering methods outperforms the traditional methods for sentiment analysis. Therefore, this paper proposes a novel metaheuristic method (CSK) which is based on K-means and cuckoo search. The proposed method has been used to find the optimum cluster-heads from the sentimental contents of Twitter dataset. The efficacy of proposed method has been tested on different Twitter datasets and compared with particle swarm optimization, differential evolution, cuckoo search, improved cuckoo search, gauss-based cuckoo search, and two n-grams methods. Experimental results and statistical analysis validate that the proposed method outperforms the existing methods. The proposed method has theoretical implications for the future research to analyze the data generated through social networks/medias. This method has also very generalized practical implications for designing a system that can provide conclusive reviews on any social issues.

Biological approach of zinc oxide nanoparticles formation and its characterization

Abstract: Herein, we are reporting a novel biological approach for the formation of zinc oxide (ZnO) nanoparticles using Maddar (Calotropis procera) latex at room temperature. X-Ray diffraction (XRD) pattern reveals the formation of ZnO nanoparticles, which shows crystallinity. Transmission electron microscopy (TEM) suggested particles size and shape in the range of 5-40 nm. Scanning electron microscopy (SEM) image reveals that the particles are of spherical and granular nature. UV-Vis absorption shows characteristic absorption peak of ZnO nanoparticles. Photoluminescence (PL) studies were performed to emphasize its emission properties. This simple and cost-effective biological approach for the formation of ZnO NPs has a promising application in biosensing, electronics and photonics. Copyright © 2011 VBRI press.

The Theory of Island Biogeography

Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201