North Eastern Hill University

About: North Eastern Hill University is a education organization based out in Shillong, Meghalaya, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 2318 authors who have published 4476 publications receiving 48894 citations.

Useful theorem on vanishing threshold contribution to sin2 theta W in a class of grand unified theories.

Abstract: Superheavy particles near the unification threshold introduce modifications to precise grand-unified-theory (GUT) predictions. We establish a very useful and general theorem valid in a class of models possessing the custodial symmetry SU(2${)}_{\mathit{L}}$\ifmmode\times\else\texttimes\fi{}SU(2${)}_{\mathit{R}}$\ifmmode\times\else\texttimes\fi{}SU(4${)}_{\mathit{C}}$\ifmmode\times\else\texttimes\fi{}P at the highest intermediate scale, according to which the one-loop GUT-threshold contribution to ${\mathrm{sin}}^{2}$${\mathrm{\ensuremath{\theta}}}_{\mathit{W}}$ by every class of superheavy particles (gauge bosons, Higgs scalars, and additional fermions) vanishes. The result also applies with supersymmetry, infinite towers, or higher-dimensional operators, and is independent of other intermediate symmetries at lower scales.

Cyanobacterial pigments and their fluorescence characteristics: applications in research and industry

Abstract: Cyanobacteria are the photoautotrophic prokaryote which poses varieties of pigments. The pigments which exhibit different colors are chlorophylls (Chls a, b, d, and f), carotenoids (β-carotene, lutein, lycopene, astaxanthin, fucoxanthin), phycobiliproteins (phycoerythrin, phycocyanin, and allophycocyanin), and scytonemin. The uses of these colorful pigments in food and cosmetic industries have been enhanced due to harmful and carcinogenic effects of synthetic dyes on humans and the environment. Lutein, fucoxanthin, and phycocyanin have medicinal importance as these pigments are exploited for treatments of eye cataract, cardiovascular and renal diseases, and chemotherapy of cancerous cells; β-carotene acts as an antioxidant and is required for the biosynthesis of rhodopsin (retina) and vitamins. Scytonemin absorbs damaging ultraviolet radiation; hence, it can be utilized as photo-protectant. Phycobilins’ fluorescence is exploited as chemical tags in the research field. Therefore cyanobacteria are the natural source of color and medicine which have high demand in the global market. This chapter primarily focuses on the characterization of cyanobacterial pigments and their industrial applications. It also elucidates the use of genetic engineering and systems biology approaches to augment the production of cyanobacterial pigments for their promising applications in research, food, cosmetics, and pharmaceuticals industries.

Synthesis and characterization of manganese(IV) and ruthenium(III) complexes derived from bis (2-hydroxy-1-naphthaldehyde)oxaloyldihydrazone

Abstract: Bis(2-hydroxy-1-naphthaldehyde)oxaloyldihydrazone(naohH4) interacts with manganese(II) acetate in methanol followed by addition of KOH giving [MnIV(naoh)(H2O)2]. Activated ruthenium(III) chloride reacts with naohH4 in methanol yielding [RuIII(naohH4)Cl(H2O)Cl2]. The replacement of aquo by heterocyclic nitrogen donor in these complexes has been observed when the reaction is carried out in presence of heterocyclic nitrogen donors such as pyridine(py), 3-picoline(3-pic) or 4-picoline(4-pic). The molar conductance values in DMF for these complexes suggest non-electrolytic nature. Magnetic moment values suggest +4 oxidation state for manganese in its complexes, however, ruthenium(III) complexes are paramagnetic with one unpaired electron. Electronic spectral studies suggest six coordinate metal ions. IR spectra reveal that naohH4 coordinates in enol-form and keto-form to manganese and ruthenium, respectively. ESR and cyclic voltammetric studies of the complexes have also been reported.