scholarly journals Macroscopic and microscopic study of integuments on ostrich (Struthio camelus) foot

2016 ◽  
Vol 60 (2) ◽  
pp. 219-226 ◽  
Author(s):  
Rui Zhang ◽  
Songsong Ma ◽  
Xiujuan Li ◽  
Gang Luo ◽  
Shuliang Xue ◽  
...  

Abstract Introduction: Ostrich characteristics include fast running, of which the probable enablers have been studied. Yet little research has taken place on one anatomical feature. It is mainly the special integuments on the ostrich foot which facilitate fast running on sand, because as point of direct sand contact they bear the whole weight and provide all the forward force. This study elucidates aspects of the integuments. Material and Methods: A stereo microscope, scanning electron microscope (SEM), and confocal scanning laser microscope were used to observe these integuments. Their surface structure was shown accurately in photographs. An SEM equipped with energy dispersive spectroscopy was used to check element contents of the upper and bottom areas and those on the lateral area of the 3rd toe. Results: The content of some chemical elements on the upper area (Mg 2.04%, Si 0.18%, P 1.97%, Ca 0.59%, and S 0.69%) was higher than that of the bottom area (Mg 0.14%, Si 0.09%, P 0.10%, Ca 0.28%, and S 0.90%). Zinc was the particular element on the upper area, while sodium, chlorine, and potassium were the specific elements on the bottom area. The parts which must withstand different frictions contained different chemical compounds. Conclusion: The microscopic plane with layer-like structure and stripes may contribute to the wear-resistance of the papillae. The polygonal and prism structures are helpful to fix papillae in a firmer way.

Author(s):  
John C. Russ

Three-dimensional (3D) images consisting of arrays of voxels can now be routinely obtained from several different types of microscopes. These include both the transmission and emission modes of the confocal scanning laser microscope (but not its most common reflection mode), the secondary ion mass spectrometer, and computed tomography using electrons, X-rays or other signals. Compared to the traditional use of serial sectioning (which includes sequential polishing of hard materials), these newer techniques eliminate difficulties of alignment of slices, and maintain uniform resolution in the depth direction. However, the resolution in the z-direction may be different from that within each image plane, which makes the voxels non-cubic and creates some difficulties for subsequent analysis.


Author(s):  
JS Deitch ◽  
KL Smith ◽  
JW Swann ◽  
JN Turner

Neurons labeled with horseradish peroxidase and reacted with diaminobenzidine (DAB) can be imaged using a confocal scanning laser microscope (CSLM) in the reflection mode. In contrast to fluorescent markers, the DAB reaction product is thought to be stable and can be observed by both light and electron microscopy. We have investigated the sensitivity of the DAB reaction product to laser irradiation, and present the spectrophotometric properties of DAB before and after exposure in the CSLM.Pyramidal neurons in slices of rat hippocampus were injected with biocytin (a biotin-lysine complex), fixed overnight in 4% paraformaldehyde, and vibratome sectioned at 75 μm. Biocytin was detected with avidin-HRP (1:200) in 0.5% Triton X-100, incubated in DAB (0.5 mg/ml) with or without 0.04% nickel ammonium sulfate (Ni), dehydrated, and imaged in a Bio Rad MRC-500 CSLM with an argon ion laser (488 and 514 nm). Spectrophotometric measurements of the soma were made on a Zeiss microspectrophotometer, as a function of laser exposure (100-1000 scans) and staining protocol.


2016 ◽  
Vol 3 ◽  
pp. 184954351667080 ◽  
Author(s):  
Ritu Malik ◽  
Ketan Pancholi ◽  
Andreas Melzer

Liposome–microbubble conjugates are considered as better targeted drug delivery vehicles compared to microbubbles alone. The microbubble in the integrated drug delivery system delivers the drug intracellularly on the target, whereas the liposome component allows loading of high drug dose and extravasation through leaky vasculature. In this work, a new high yielding microbubble production method was used to prepare microbubbles for formulation of the liposome-conjugated drug delivery system. In formulation process, the prepared liposome of 200 nm diameter was attached to the microbubble surface using the avidin–biotin interaction. The analysis of the confocal scanning laser microscope images showed that approximately 8 × 108 microbubbles per millilitre (range: 2–7 μm, mean size 5 ± 0.5 μm) can be efficiently conjugated to the liposomes. The method of conjugation was found to be effective in attaching liposome to microbubbles.


Nephron ◽  
1995 ◽  
Vol 70 (2) ◽  
pp. 171-179 ◽  
Author(s):  
Toru Hyodo ◽  
Ikuo Miyagawa ◽  
Akihiro Iino ◽  
Koji Ono ◽  
Tsutomu Kuomi ◽  
...  

2010 ◽  
Vol 654-656 ◽  
pp. 715-718 ◽  
Author(s):  
Itsuya Sato ◽  
Seiji Miura ◽  
Tetsuo Mohri

A commercial Mg alloy, AZ31B, has been used widely. In the texture of AZ31B sheet, each grain has its c-axis almost parallel to the sheet normal. Therefore, at the bending process of the sheet, basal slip system can not accommodate an in-plane plastic strain which is perpendicular to the c-axis of each grain. It is known that {10―,12} twin can be formed by applying an extension strain parallel to the c-axis, which is equivalent to the a-axis compression strain. So in the bending deformation of the AZ31B sheet with a texture microstructure, it is expected that {10―,12} twinning occurs. In this study, an in-situ bending test of AZ31B sheet with a texture was conducted under a confocal scanning laser microscope to observe twinning by applying compression stress along a direction almost perpendicular to the c-axis of grains. In addition, EBSD techniques were used for the analysis of crystal orientations. The process of twin development observed by the in-situ bending test can be summarized as follows; with the increase of the deformation strain, the total area of twins increases. However, it is noted that the growth of twins is apparent while the number of twins is almost constant during plastic bending deformmation. EBSD analysis suggested that twinning behavior obey Schmid’s law even in the polycrystal.


2009 ◽  
Vol 283-286 ◽  
pp. 425-431 ◽  
Author(s):  
Laura M. Fernandez Diaz ◽  
Jing Zhu ◽  
Gordon R. Holcomb ◽  
Paul D. Jablonski ◽  
David E. Alman ◽  
...  

It is known that additions of reactive elements such as Ce, La or Y improve the properties of protective oxide-scales on Ni and Fe based alloys [ - ] by increasing oxide adhesion, decreasing the transient time until a continuous Cr2O3 layer is formed and decreasing the parabolic rate constant. Nevertheless, the precise roles played by these reactive elements to improve scales and the precise mechanisms by which they are incorporated into the scale during the surface treatment processes are unknown. Although they are believed to be associated with transport properties in the scale, it is not clear how this occurs or why it improves oxidation resistance. This project is aimed to gain understanding of the scale evolution in Fe-22 wt.% Cr alloys at 800 oC in dry air during the transient stage after 15 minutes of oxidation. The effect of La (120 and 290 ppm) and Ce (270 and 610 ppm) additions added during melt-stage processing are investigated. The surface oxidation process was imaged in-situ through a Confocal Scanning Laser Microscope (CSLM) and the results were correlated with post-experiment characterization through FEG-SEM and FIB-SEM combined with 3D reconstruction. The roles of rare-earth oxide particles on nucleation of Cr2O3 and blockage of short-circuit diffusion paths in the oxide scale and underlying metal are discussed.


Sign in / Sign up

Export Citation Format

Share Document