31 research outputs found
Phase evolution of EBPVD coated ceria-zirconia nanostructure and its impact on high temperature oxidation of AISI 304.
The present work focusses on the effect of nanocrystalline xCeO2 – (1-x)ZrO2 (x = 1, 0.75, 0.5, 0.25 and 0 in wt% abbreviated as C100, C75Z25, C50Z50, C25Z75 and Z100) coated by electron beam physical vapour deposition (EBPVD) on AISI 304 and its implication on the high-temperature oxidation protection. The oxidation kinetics indicate that the samples C100, C75Z25 and C50Z50 show 3–4 orders better oxidation protection than uncoated AISI 304. Coating morphology and composition play an important role in developing superior nanostructures against high temperature oxidation. The development of ceria-zirconia coating helps in the realization of structural materials for elevated temperature application
Study of the small heat shock proteins in the normal and wooden breast chicken muscles
A new myopathy called “wooden breast” affecting Pectoralis major muscles of broilers was described by researchers in Finland and other countries and it has affected the economy of the poultry industry in the last few years. The exact mechanisms behind this myopathy are yet to be discovered. This study focused on establishing any relationship between this new myodegeneration disorder “wooden breast” and small heat shock proteins. The primary aim of this work was to study the 3 important small heat shock proteins such as HSP20, HSP27 and αβ-crystallin in wooden breast and normal breast fillets by means of immunoblot technique. Six random fillet samples identified as wooden breast and six normal breast muscle samples were selected for this study.
The presence of small heat shock protein HSP27 was comparatively higher in wooden breast muscles in both the myofibrillar fraction (p-value = 0. 02) and sarcoplasmic muscle fraction (p-value = 0. 01) than their presence in the normal breast muscles. Stress suffered by the birds belonging to the wooden breast condition is suggested to upregulate the heat shock proteins to antagonize against protein misfolding, protein denaturation and for protection of myofibrillar and structural proteins.
As an outcome of the study, a proposal can be made about the possible mechanism behind the wooden breast to be ischemia and heat stress causing the upregulation of heat shock proteins, which was supported by the presence of HSP27 in both the myofibrillar and the sarcoplasmic muscle fraction. The presence of a relative higher amount of HSP27 in wooden breast muscles suggests that they defend against the stress suffered by the bird. Detecting the exact time point of onset of stress and factors causing the stress might unravel more information about this disorder, and studying the presence of small heat shock proteins at different time points post slaughter till the start of rigor mortis might provide additional details behind this muscle disorder
