Serial cytological assay of micronucleus induction: a new tool to predict human cancer radiosensitivity

The role of the propeptide sequence and a disulfide bridge between sites 1 and 122 in chymotrypsin has been examined by comparing enzyme activities of wild-type and mutant enzymes. The kinetic constants of mutants devoid of the Cys1-Cys122 disulfide-linked propeptide show that this linkage is not important either for activity or substrate specificity. However this linkage appears to be the major factor in keeping the zymogen stable against non-specific activation. A comparison of zymogen stabilities showed that the trypsinogen propeptide is ten times more effective than the chymotrypsinogen propeptide in preventing non-specific zymogen activation during heterologous expression and secretion from yeast. This feature can also be transferred in trans to chymotrypsinogen; i.e. the chymotrypsin trypsin propeptide chimera forms a stable zymogen.     

Optimisation and comparative study on the addition of shrimp protein hydrolysate and shrimp powder on physicochemical properties of extruded snack

The effect of an addition of shrimp protein hydrolysate and shrimp powder on the physicochemical properties of extruded snack was studied. Rice flour and cornflour were used as base materials, and extrusion was done using corotating twin‐screw extruder. A mixture response surface methodology was used to study the effect of ingredient mixture on the physical, functional and sensory properties of extrudates. Linear and quadratic mixture response regression model was fitted to the response variables, and it was evaluated using R² values. Based on the desirability function score, the optimum combination of ingredient was 47.75% rice flour, 38.64% cornflour, 5.95% hydrolysate and 7.67% shrimp protein powder. It was observed that an addition of shrimp hydrolysate more than 5% (7.5%) improved the crispiness. Sensory evaluation revealed that shrimp hydrolysate and shrimp powder can be used at 5–7.5% level for developing protein‐rich extruded products without affecting sensory characteristics.     

Influence of plasticizers and cryogenic grinding on the high‐cooling‐rate solidification behavior of PBT/PET blends

Two structurally different plasticizers (cyclic and linear) and the effect of cryogenic grinding on the solidification behavior at high cooling rates by a continuous cooling transformation approach of poly(butylene terephthalate)/poly(ethylene terephthalate), PBT/PET, blends are described. The solidification curve (density versus cooling rate) is confirmed as an effective tool to compare the differences in crystallization behavior under conditions mimicking processing. In comparison to the bulky cyclic plasticizer, the linear oligomeric one was found to have a more pronounced influence on the crystallization behavior. A 60/40 by weight PBT/PET blend shows a drop‐off of density at ～50 K/s. In the plasticized sample, the long‐range crystalline order appears up to a cooling rate of ～250K/s, making the blend comparable to pure PBT. Grinding the components before blending further improves crystallizability and synergy to the addition of the plasticizer. The results suggest the important role of local chain mobility in the solidification behavior at high cooling rates. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43083.     

Green Nanocomposites of Natural Rubber/ Olivine Nanosilica: Viscoelastic,Mechanical, Transport and Thermal Characterizations

Silicon - Nanosilica was synthesized from a low cost raw material, olivine by a more sustainable and cost effective method. The pure nanosilica obtained was amorphous in nature with a surface area...     

Development and optimization of fish‐fortified instant noodles using response surface methodology

Proper and sensible formulation of ingredients in noodles facilitates its calorie cut down thus making it healthier. Fish being a source of cheap and quality protein can serve in the fortification of noodles. Hence, a study was done to formulate and develop fish noodles from Nemipterus japonicus. D‐optimal mixture experimental design with 15 runs was formulated to optimise the different levels of ingredients for noodles. Influence of different ingredients, viz. fish mince, wheat and refined wheat flour (maida) and potato starch, on the physical, cooking and sensory properties of fish noodles was evaluated. The protein content of noodles increased with increase in the fish mince incorporation. Water absorption capacity (WAC) was found to be directly related to the potato starch concentration. Positive correlation was observed between noodle protein content and cooking time. Desirability function scores revealed a noodle combination of 45% fish mince, 47% wheat: maida (1:1) mix and 8% potato starch as optimum.     

Stress corrosion crack velocity and grain boundary precipitates in an Al-Zn-Mg alloy

The fracture kinetics of Al-5.5 Zn-2.5 Mg alloys submersed in 3 pct NaCl-H₂O solutions were varied by heat treatment. The steady state velocity, on a plot of velocity vs stress intensity, was compared with microstructure and it was found to be inversely proportional to the volume of MgZn₂ in the grain boundary. This behavior suggests that grain boundary precipitates can act as sacrificial anodes to retard intergranular stress corrosion cracking. Formerly Graduate Student at the University of Connecticut     

Exposure to enriched environment improves spatial learning performances and enhances cell density but not choline acetyltransferase activity in the hippocampus of ventral subicular-lesioned rats.

The authors demonstrated the efficacy of enriched housing conditions in promoting the behavioral recovery and neuronal survival following subicular lesion in rats. Chemical lesioning of the ventral subiculum impaired the spatial learning performances in rats. The lesion also induced a significant degree of neurodegeneration in the CA1 and CA3 areas of the hippocampus and entorhinal cortex. Exposure to enriched housing conditions improved the behavioral performance and partially attenuated the neurodegeneration in the hippocampus. The choline acetyl transferase (ChAT) activity in the hippocampus remained unchanged following ventral subicular lesion and also following exposure to an enriched environment. The study implicates the effectiveness of activity-dependent neuronal plasticity induced by environmental enrichment in adulthood following brain insult. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Doped oxides of cerium as inorganic colorants

The colour of inorganic colorants is based on metal ions such as cadmium, lead, chromium or cobalt, the majority of which are unfortunately potentially toxic. Thus, there is in a need to introduce alternative metal or metal oxides, which would be environmentally friendly and economically viable as a replacement for potentially toxic inorganic colorants. Rare earth-based colorants offer an additional opportunity for the development of optically pure colours. In this study, a replacement for potentially toxic colorants has been sought through the use of a rare earth metal ion, cerium. Appropriate doping of cerium oxides with molybdenum and iron gives an orange–red colorant. The conditions ideal for optimal colour have been standardised and the resultant colorant characterised through powder X-ray diffraction techniques, particle size measurement, etc. The colorants exhibit good hiding power and tinting strength.