Central University of Kerala

About: Central University of Kerala is a education organization based out in Kāsaragod, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 556 authors who have published 881 publications receiving 7474 citations.

Optical Properties of Metal, Semiconductor and Ceramic Nanostructures Grown by Liquid Phase-Pulsed Laser Ablation

Abstract: Low-dimensional nanomaterials with enhanced size effect properties such as surface plasmon resonance and quantum confinements offer an unprecedented physical phenomenon, reducing devices down to atomic scale. In the last few decades, research interest in nanostructured materials has aroused due to their unusual electronic, optical, magnetic and chemical properties which are different from their bulk counterpart. In recent years, great efforts have been made on the synthesis of colloidal nanoparticles because of their promising application in various fields such as drug delivery, imaging and diagnostics. In this chapter, we discuss the synthesis of metal, semiconductor and ceramic nanoparticles by liquid phase-pulsed laser ablation (LP-PLA) technique. The optical properties of gold and silver nanoparticles grown by LP-PLA method were discussed in detail in this chapter. This chapter also discusses the growth of surfactant-free highly luminescent, transparent, chemically pure and biocompatible zinc oxide (ZnO) nanoparticles by LP-PLA. The dependence of time of ablation, laser fluence, oxygen and nitrogen bubbling during ablation on the properties of the ZnO nanoparticles was investigated. The growth of ZnO nanoparticles by varying the pH of the media gives some inference on the stability of this colloidal solution and the formation of passivation layer on the surface of these particles. The luminescent properties of the europium-doped hydroxyapatite grown by LP-PLA technique were also discussed in this chapter. These luminescent nanoparticles find immense applications in biomedical imaging and cancer detections.

Rhizosphere impacts bacterial community structure in the tea ( <i>Camellia sinensis</i> (L.) <i>O</i> . <i>Kuntze</i> .) estates of Darjeeling, India

Abstract: India contributes 28% of the world's tea production, and the Darjeeling tea of India is a world-famous tea variety known for its unique quality, flavour and aroma. This study analyzed the spatial distribution of bacterial communities in the tea rhizosphere of six different tea estates at different altitudes. The organic carbon, total nitrogen and available phosphate were higher in the rhizosphere soils than the bulk soils, irrespective of the sites. Alpha and beta diversities were significantly (p < 0.05) higher in the bulk soil than in the rhizosphere. Among the identified phyla, the predominant ones were Proteobacteria, Actinobacteria and Acidobacteria. At the genus level, only four out of 23 predominant genera (>1% relative abundance) could be classified, viz., Candidatus Solibacter (5.36 ± 0.36%), Rhodoplanes (4.87 ± 0.3%), Candidatus Koribacter (2.3 ± 0.67%), Prevotella (1.49 ± 0.26%). The rhizosphere effect was prominent from the significant depletion of more ASVs (n = 39) compared to enrichment (n = 11). The functional genes also exhibit a similar trend with the enrichment of N2 fixation genes, disease suppression and Acetoin synthesis. Our study reports that the rhizobiome of tea is highly selective by reducing the alpha and beta diversity while enriching the significant functional genes.

Effect of anisotropy on nonlinear surface plasmon polaritons in anisotropic/metal/nonlinear slab waveguides

Abstract: The nonlinear surface plasmon polariton (SPP) supported by a linear/metal-nonlinear slab waveguide was studied analytically. The dispersion conditions were obtained from fundamental Maxwell’s equations to determine the propagation characteristics of the nonlinear SPPs supported by the waveguide. The mode profile of the nonlinear mode was studied to analyze the physics behind the observed propagation characteristics. After studying propagation characteristics of the mode, the linear layer was replaced with a layer containing a uniaxial material. The effect of optical anisotropy of the layer on the dispersion characteristics of the nonlinear SPPs was investigated to understand the possible tunability of the mode. It has been observed that the propagation characteristics of modes supported by the waveguide can be tuned with the help of an anisotropic medium. The guiding structure could find application in the tunable components in all-optical integrated chips.

Reproductive System in the Male Phase of a Parasitic Isopod (Crustacea) - Morphological, Histological and Ultrastructural Evidence for Sequential Protandrous Hermaphroditic Changes.

Abstract: This paper reports the protandric hermaphroditic changes in the reproductive system of the male-phased Norileca indica, a cymothoid that parasitizes the scombrid fish Rastrelliger kanagurta. Each part of N. indica's paired reproductive system lies on either side of the gut. This study considers the three successive size classes of the male phase - designated as M1, M2 and M3 - using light microscopy and ultrastructural methods. The testis comprises of three bulged sac-like lobes labelled t1, t2 and t3, all of which open into the ovary of their respective side. The vas deferens, which emerges as a posterior extension of the ovary, opens into the penis and the distal end of each oviduct leads to a sealed gonopore on their respective sides. Each testis lobe (t1/t2/t3) displays clusters of germ cells undergoing stage-specific differentiation. Spermatids undergoing sequential changes associated with spermiogenesis keep close proximity to somatic accessory cells. The characteristic histological changes associated with protandric hermaphroditism are visible in the ovaries of sequential size classes (M1, M2 and M3). In early M1, besides spermatophores, the ovary has abundant polymorphic nuclei; in the mid/late M1, the posterior ovary has abundant spermatophores, anterior displayed oogonia, previtellogenic oocytes and two distinct forms of follicle cells. In M2, the anterior ovary shows compactly arranged oocytes while the posterior region accommodates spermatophores - fewer, however, than during M1. The entire ovary during M3 is crowded with previtellogenic oocytes, which marginalize the spermatophore passage. The vas deferens of the smallest M1 lack spermatophores. As the size class progresses through late M1 into M2 and M3, the posterior vas deferens is filled with spermatophores, which closely associate with the glandular epithelial lining.

Emerging role of pioneer transcription factors in targeted ERα positive breast cancer

Abstract: Transcription factors (TFs) are modular protein groups that preferably bind to DNA sequences and guide genomic expression through transcription. Among these key regulators, “pioneer factors” are an emerging class of TFs that specifically interact with nucleosomal DNA and facilitate accessible genomic binding sites for the additional TFs. There is growing evidence of these specialized modulators in particular malignancies, as highlighted by agents’ clinical efficacy, specifically targeting nuclear hormone receptors. They have been implicated in multiple cancers more recently, with a high proportion inculpating on hormone influential cancers. Moreover, extended crosstalk and cooperation between ERα pioneering factors in estrogendependent breast cancer (BC) remain elucidated. This review discusses on the recent advances in our understanding of pioneer TFs in cancer, especially highlighting its potentiality to modulate chromatin condensation to permit ERα recruitment in BC cells. Through the study it was concluded that the highly prospected pioneer TFs in BC, including FOXA1, TLE1, PBX1, and GATA3, possess the potential therapeutic significance and further innovations in the field could yield targeted therapy in cancer treatment.