The analysis of charge transport mechanism in mixed ionic electronic conductor composite of Sr2TiCoO6double perovskite with yttria stabilized zirconia.

In this investigation, the ionic conduction mechanism in mixed ionic electronic conductors composites of Sr2TiCoO6/YSZ has been studied with the help of universal dynamic response. 3 mol% and 8 mol% yttria stabilized ZrO2have been mixed with Sr2TiCoO6(STC) double perovskite in 1:1 ratio to prepare STC/3YSZ and STC/8YSZ composites via solid-state reaction route. AC Impedance spectroscopy has been carried out to examine the charge transport mechanism, which has been modeled using the microstructural networks of resistors and capacitors. Grain boundaries are more resistive and capacitive compared to the bulk. Modulus spectroscopy analysis demonstrates the non-Debye character of conductivity relaxation with frequency. Complex frequency-dependent AC conductivity is found to obey Almond West power law and reveals that ion migration occurs through the correlated hopping mechanism. Further, the DC conductivity and relaxation time have been found to follow the Barton Nakajima and Namikawa relation, which is correlated with AC to DC conduction. The time-temperature superposition principle has been used to explain the conductivity scaling in the intermediate frequency range. At low temperatures, the ions are localized in the asymmetric potential well, while at high temperatures, hopping behavior starts dominating. Further Kramers-Kronig transformation connects the dielectric strength with conductivity relaxation and verifies the impedance data.

A study on steroidogenic elaborations of stroma and their regulation in response to ovarian hormones in goats.

Stromal tissue is an essential componenlt of the ovary not only for providing structural support but also for contributing to the early follicular growth with their bi-directional paracrine signaling. Estradiol is a major female hormone mainly secreted by the follicular cells in the ovary. To examine the relationship between 17ß-estradiol and the factors involved in androgen production in stromal cells, ovarian stromal cells were cultured in the graded concentrations (50 and 100 ng/mL) of 17ß-estradiol for varying time periods (24 and 48 h). The cells were processed for transmission electron microscopy to study the changes in steroidogenic functions of the cells. The effect of estradiol treatment was also evaluated on the quantity of androgen production and abundance of steroidogenic enzymes and proteins. The results indicated 17ß-estradiol increased androgen production in ovarian stromal cells. In addition to enhanced androstenedione and testosterone production, estradiol stimulation was also based on the marked increase in abundance of mRNA transcript of steroidogenic enzymes [Star (Steroidogenic Acute Regulatory Protein), Cyp11a1, Cyp17a1, and hsd3b1 (3ß-hydroxysteroid dehydrogenase)], as well as abundances of StAR and CYP11A1 protein. Thus, 17ß-estradiol enhanced steroidogenesis in ovarian stromal cells. This study provided a basis for further exploration of regulation of steroidogenesis in ovarian stromal cells and the feedback mechanisms in association with estradiol.

Seasonal effect in expression of AQP1, AQP3 and AQP5 in skin of Murrah buffaloes.

Aquaporins are transmembrane protein channels which are known to help the passage of water and solutes across the cell membranes. AQP1, AQP3 and AQP5 are isoforms of aquaporin known to aid in transepithelial water movement. AQP3 is also known to aid in glycerol transport. The present study was conducted to investigate the role of AQP1, AQP3 and AQP5 in thermoregulation of buffaloes by probing the expression of the genes in skin of buffaloes during different season viz. winter, spring and summer. The skin tissue samples were collected from the neck region of Murrah buffaloes (n = 12) and analyzed for gene expression by RT-PCR and immunolocalization. The physiological responses including respiration rate, rectal temperature and neck skin temperature observed during summer were significantly higher than winter and spring seasons. The study revealed the expression of AQP1, AQP3 and AQP5 genes in skin samples. The relative mRNA expressions of AQP1, AQP3 and AQP5 in skin relative to spring season were 1.41 ± 0.47, 1.95 ± 0.22 and 6.77 ± 1.02 folds during summer which were significantly higher than other seasons. The up-regulation of the expression of the studied AQPs were concomitant with the increase in physiological responses including skin temperature and sweating rate during summer. During summer season, AQP1 were mostly immunolocalized in the walls of skin blood capillaries, while AQP3 were observed mostly in the epidermal layer of the skin. The immunolocalization of AQP5 were mostly observed in the secretory glands of skin. The up-regulation of AQP1, AQP3 and AQP5 in skin during summer season indicates their role in thermoregulation of buffaloes.

An immunological approach of sperm sexing and different methods for identification of X- and Y-chromosome bearing sperm.

Separation of X- and Y-chromosome bearing sperm has been practiced for selection of desired sex of offspring to increase the profit in livestock industries. At present, fluorescence-activated cell sorter is the only successful method for separation of X- and Y-chromosome bearing sperm. This technology is based on the differences in DNA content between these two types of sperm and has been commercialized for bovine sperm. However, this technology still has problems in terms of high economic cost, sperm damage, and lower pregnancy rates compared to unsorted semen. Therefore, an inexpensive, convenient, and non-invasive approach for sperm sexing would be of benefit to agricultural sector. Within this perspective, immunological sperm sexing method is one of the attractive choices to separate X- and Y-chromosome bearing sperm. This article reviews the current knowledge about immunological approaches, viz., H-Y antigen, sex-specific antigens, and differentially expressed proteins for sperm sexing. Moreover, this review also highlighted the different methods for identification of X- and Y-sperm.