Do lipases and amylases of an endangered Indian carp Hypselobarbus pulchellus play a role in visceral fat dynamics; evidence of in vitro macromolecular interactions.

Fat depots or triglycerides are hydrolysed by the action of lipases in fish to be used for energy and/or for growth and reproduction. In herbivores fishes, de novo synthesis of lipids from non- lipid substrates (glucose) leads to fat deposits and/or fatty infiltration in organs especially on ovaries limiting its normal functions. This study was aimed to understand lipases from the digestive tract (DT) of adult Hypselobarbus pulchellus of different sizes, their partial purification, characterisation and their isozymes. In-vitro hydrolysis study on interaction of carbohydrate with proteins was evaluated to establish specific protein selection that combat undue glucose release. Results of the study identified four lipase isoenzymes of ~ mol. wt 19.88, 24.29, 32.86, 54.56 kDa with optimal pH of 3.5 and 8, pH stability between pH 5.5-10; optimal temperature at 35 °C and heat stability between 35 and 45 °C. Characterisation studies indicated presence of thiol group in their active site and Ca, Na and Zn ions activated lipase activity. Rice bran as carbohydrate source when used along with azolla (plant protein) and fish meal (animal protein) may combat undue release of excess glucose that leads to visceral fat formation in H. pulchellus as assessed from in vitro studies.

On-chip cooling by superlattice-based thin-film thermoelectrics.

There is a significant need for site-specific and on-demand cooling in electronic, optoelectronic and bioanalytical devices, where cooling is currently achieved by the use of bulky and/or over-designed system-level solutions. Thermoelectric devices can address these limitations while also enabling energy-efficient solutions, and significant progress has been made in the development of nanostructured thermoelectric materials with enhanced figures-of-merit. However, fully functional practical thermoelectric coolers have not been made from these nanomaterials due to the enormous difficulties in integrating nanoscale materials into microscale devices and packaged macroscale systems. Here, we show the integration of thermoelectric coolers fabricated from nanostructured Bi2Te3-based thin-film superlattices into state-of-the-art electronic packages. We report cooling of as much as 15 degrees C at the targeted region on a silicon chip with a high ( approximately 1,300 W cm-2) heat flux. This is the first demonstration of viable chip-scale refrigeration technology and has the potential to enable a wide range of currently thermally limited applications.