Comparative transmission electron microscopic studies on eosinophil of non ruminants

2016 ◽  
Author(s):  
S. Mehta ◽  
A. P. Minj
Keyword(s):  
Cell Organelles ◽  
Electron Microscopic ◽  
Double Membrane ◽  
Cytoplasmic Granules ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies ◽  
Membrane Bound ◽  
Cytoplasmic Processes ◽  
Apparently Healthy

Transmission electron microscopic studies of eosinophil of horse, dog, pig and rabbit were carried out on six apparently healthy animals of each species. Ultrastructurally the eosinophils appeared round to oval in shape with few, short and narrow cytoplasmic processes in horse, oval with numerous long and wide cytoplasmic processes in dog and round with thin and broad small cytoplasmic processes in pig. While in rabbit it was round to oval in shape with long cytoplasmic processes. The nucleus had two to three lobes in all the animals. In all the four species it was observed that the heterochromatin was concentrated towards the periphery. Granules were mostly oval in outline and more or less similar in shape and size in horse while in dog the granules were rounded in shape and medium sized. In pig the double membrane bound cytoplasmic granules were roughly rounded to oval in shape and distributed throughout the cytoplasm. The granules in rabbit were mostly oval in outline and more or less similar in dimension. Cell organelles were clearly visible in the cytoplasm of horse while poorly visible in dog, pig and rabbit.

Radial mass analysis of unstained STEM images of molluscan hemocyanins

1990 ◽  
Vol 48 (3) ◽  
pp. 810-811
Author(s):  
M.G. Hamilton ◽  
T.T. Herskovits ◽  
J.S. Wall
Keyword(s):  
Image Analysis ◽  
Hollow Cylinder ◽  
Electron Micrographs ◽  
Side View ◽  
Mass Analysis ◽  
Mass Measurements ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies

The hemocyanins of molluscs are aggregates of a cylindrical decameric subparticle that assembles into di-, tri-, tetra-, penta-, and larger multi-decameric particles with masses that are multiples of the 4.4 Md decamer. Electron micrographs of these hemocyanins typically show the particles with two profiles: circular representing the cylinder viewed from the end and rectangular representing the side-view of the hollow cylinder.The model proposed by Mellema and Klug from image analysis of a didecameric hemocyanin with the two decamers facing one another with collar (closed) ends outward fits the appearance of side-views of the negatively-stained cylinders. These authors also suggested that there might be caps at the ends. In one of a series of transmission electron microscopic studies of molluscan hemocyanins, Siezen and Van Bruggen supported the Mellema-Klug model, but stated that they had never observed a cap component. With STEM we have tested the end cap hypothesis by direct mass measurements across the end-views of unstained particles.

Synthesis of nanometer-sized particles of barium orthotitanate prepared through a modified reverse micellar route: Structural characterization, phase stability and dielectric properties

2004 ◽  
Vol 19 (10) ◽  
pp. 2905-2912 ◽  
Author(s):  
Tokeer Ahmad ◽  
Ashok K. Ganguli
Keyword(s):  
Martensitic Transition ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies ◽  
Size Of Particles ◽  
Reverse Micellar

Nanoparticles of barium orthotitanate (Ba2TiO4) was obtained using microemulsions (avoiding Ba-alkoxide). Powder x-ray diffraction studies of the powder after calcining at 800 °C resulted in a mixture of orthorhombic (70%) and monoclinic (30%) phases. The high-temperature orthorhombic form present at 800 °C was due to the small size of particles obtained by the reverse micellar route. Pure orthorhombic Ba2TiO4 was obtained on further sintering at 1000 °C with lattice parameters a = 6.101(2) Å, b =22.94(1) Å, c = 10.533(2) Å (space group, P21nb). The particle size obtained from x-ray line broadening studies and transmission electron microscopic studies was found to be 40–50 nm for the powder obtained after heating at 800 °C. Sintering at 1000 °C showed increase in grain size up to 150 nm. Our studies corroborate well with the presence of a martensitic transition in Ba2TiO4. The dielectric constant was found to be 40 for Ba2TiO4 (at 100 kHz) for samples sintered at 1000 °C. The dielectric loss obtained was low (0.06) at 100 kHz.

Sign in / Sign up

Export Citation Format

Share Document