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Named Entity Recognition (NER) also known as entity extraction plays an important role in identifying and classifying the named entities into different categories like name of person, place, organization, things, quantity, monetary value etc. that appear in a document. NER has applications in various Natural Language Processing (NLP) tasks such as information retrieval, question answering system, Machine Translation, Sentiment Analysis. NER systems can be developed using rule based, machine learning or hybrid approach. Now Deep learning is being used to develop efficient NER as these models are capable of learning patterns easily and efficiently. Quite a large number of work has been done in English compared to the work done for Indian Languages. The focus of this paper is to highlight the challenges in building an efficient NER for one of the south Indian language namely Malayalam. The different issues that we need to address in order to develop an efficient NER for Malayalam is presented.

Levamisole is an imidothiazole derivative with a wide variety of applications in medical field. It has long been used as an anti-helminthic where its primary action is through the opening of acetyl choline receptor channels. It is widely used as an immunomodulatory drug through its action on dentritic cells and by enhancing the release of cytokines like interleukins 12 and 10. The antioxidant action of levamisole is by the enhancing effect on the major cellular redox systems like glutathione, enzymes like superoxide dismutase, catalase and also possible effects on glutathione related enzymes. On the other hand, the anti-inflammatory action is by the inhibition of TNF-alpha (tumor necrosis factor) and interleukin 6. Anti-neoplastic action of levamisole is by two ways that is, through its apoptotic action causing cell cycle inhibition and increased endothelial cell adhesion and the second action is through its anti-angiogenic property. This article enlightens upon the various mechanisms of action of levamisole at molecular level describing its diverse uses as an anti-helminthic, immunomodulatory, anti-neoplastic, anti-inflammatory and antioxidant drug.

In this work, we report the synthesis of two receptors for fluoride ions based on acyl hydrazone, such as N'-[(1Z)-1-(4-fluorophenyl)ethylidene]benzohydrazide (R1) and N'-[(1Z)-1-(2-hydroxyphenyl)ethylidene]benzohydrazide (R2). The receptors R1 and R2 were synthesized from the corresponding ketones and benzoic acid hydrazide and characterized spectroscopically by UV-visible, IR and 1HNMR techniques. The response of R1 and R2 towards different anions was studied colourimetrically in acetonitrile. The receptors exhibited a specific response towards fluoride ions. Further studies of 1:1 composition of receptors, R1/R2:fluoride ions by different spectroscopic techniques such as UV-Visible, IR and 1HNMR spectroscopy indicated the participation of -NH proton of the receptors in the sensing action through the hydrogen bonding. To understand the mechanism, Time-Dependent Density Functional Theory (TD-DFT) studies were done using the CAM-B3LYP/6311G++ (3df,2p) with Grimme's D3BJ empirical dispersion basis set. The studies supported the role of hydrogen bonding interaction of -NH and-OH protons of the receptors with the fluoride ions.