scholarly journals External Morphology and Ultrastructure of Tegumental Glands of Aegla platensis (Crustacea, Anomura, Aeglidae) Pleopods: Might They Play A Role in Egg Attachment?

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Tainã Gonçalves Loureiro ◽  
Mauricio Pereira Almerão ◽  
Maria Cristina Faccioni-Heuser ◽  
Georgina Bond-Buckup ◽  
Paula Beatriz De Araujo
Keyword(s):  
Electron Microscopy ◽  
Distal Region ◽  
External Morphology ◽  
Secretory Cells ◽  
Egg Incubation ◽  
Transmission Electron ◽  
Microscopy Techniques ◽  
Female Abdomen ◽  
Attachment Process ◽  
Care Behavior

Egg incubation on the female abdomen is the parental care behavior observed in aeglids, in which eggs are kept adhered to maternal pleopods and maintained, cleaned and aerated. In A. platensis, egg attachment occurs with the aid of pleopodal setae, which are twisted around their axis in the distal region, forming the funiculus, and pleopodal glands, which are responsible for the production of the adhesive substance that seems to be involved in egg fixation to pleopodal setae. Those glands are acini formed by secretory cells arranged concentrically around a central duct, giving them a rosette appearance. Two types of secretory cells were observed, those that produce electron-lucid vesicles and those having electron-dense ones. Both kinds of vesicles are released in a duct whose opening pore is located on the pleopodal surface and constitute the adhesive substance that coats eggs and pleopodal setae, ensuring egg fixation to the female body and maternal care maintenance. This study investigates the internal and external morphology of Aegla platensis pleopods, to understand the egg attachment process and identify the structures involved in this phenomenon. Three microscopy techniques are used: scanning electron microscopy (SEM), transmission electron microscopy (TEM), and optical microscopy (OM).

Ultrastructural studies of the relationship between actin filaments and secretory granules

1990 ◽  
Vol 48 (3) ◽  
pp. 458-459
Author(s):  
Ellen Holm Nielsen
Keyword(s):  
Electron Microscopy ◽  
Colloidal Gold ◽  
Actin Filaments ◽  
Secretory Granules ◽  
Secretory Cells ◽  
Ultrastructural Studies ◽  
Transmission Electron ◽  
Granule Membrane ◽  
Ultrathin Sections ◽  
Lowicryl K4m

In secretory cells a dense and complex network of actin filaments is seen in the subplasmalemmal space attached to the cell membrane. During exocytosis this network is undergoing a rearrangement facilitating access of granules to plasma membrane in order that fusion of the membranes can take place. A filamentous network related to secretory granules has been reported, but its structural organization and composition have not been examined, although this network may be important for exocytosis.Samples of peritoneal mast cells were frozen at -70°C and thawed at 4°C in order to rupture the cells in such a gentle way that the granule membrane is still intact. Unruptured and ruptured cells were fixed in 2% paraformaldehyde and 0.075% glutaraldehyde, dehydrated in ethanol. For TEM (transmission electron microscopy) cells were embedded in Lowicryl K4M at -35°C and for SEM (scanning electron microscopy) they were placed on copper blocks, critical point dried and coated. For immunoelectron microscopy ultrathin sections were incubated with monoclonal anti-actin and colloidal gold labelled IgM. Ruptured cells were also placed on cover glasses, prefixed, and incubated with anti-actin and colloidal gold labelled IgM.

scholarly journals Ultrastructure of the adrenal gland of paca (Cuniculus paca, Linnaeus, 1766) in captivity

2021 ◽  
Vol 15 (3) ◽  
pp. 203-208
Author(s):  
Sérgio Pinter Garcia Filho ◽  
Leandro Luis Martins ◽  
Paulo Fernandes Marcusso ◽  
Tais Harumi de Castro Sasahara ◽  
Márcia Rita Fernandes Machado
Keyword(s):  
Electron Microscopy ◽  
Adrenal Gland ◽  
Adrenal Glands ◽  
Comparative Anatomy ◽  
The Body ◽  
Cortical Region ◽  
Lateral Incision ◽  
Transmission Electron ◽  
In Captivity ◽  
Microscopy Techniques

Lowland paca (Cuniculus paca, Linnaeus, 1766) is a medium-sized rodent that belongs to the Brazilian fauna. Yet little information on its morphology is found in the specialized literature. Thus, the objective of the work was to study the morphology of the adrenal gland of paca by means of microscopic ultrastructure analysis. The adrenal gland secretes specialized substances in the body which promote biological functions of great importance and will provide valuable information to studies in comparative anatomy. Two (2) adult lowland pacas were used, male and female. Soon after death, the animals were positioned in the supine position; their abdominal cavities were opened by pre-retro umbilical and lateral incision followed by folding of the abdominal walls to expose the glands. The adrenal glands were removed; fragments were collected, fixed and prepared for ultrastructure observations using scanning electron microscopy and transmission electron microscopy techniques. It was observed that the adrenal glands of the paca have divisions as well as the limits of the cortical and medullary region, as well as the subdivisions of the glomerulosa, fasciculated and reticulated areas of the cortical region as in other rodents. An ultrastructure of cells and their components also showed a lot of similarity to that already demonstrated in different rodents.

Paracrystalline bundles of large tubules, induced in vitro by Mebendazole in Cysticercus cellulosae

Parasitology ◽  
1981 ◽  
Vol 83 (3) ◽  
pp. 513-518 ◽  
Author(s):  
J. P. Laclette ◽  
Marie Therese Merchant ◽  
Kaethe Willms ◽  
L. Cañedo
Keyword(s):  
Electron Microscopy ◽  
Culture Medium ◽  
Morphological Changes ◽  
Bladder Wall ◽  
Secretory Cells ◽  
External Diameter ◽  
Nematode Larvae ◽  
Transmission Electron ◽  
Cysticercus Cellulosae

SUMMARYThe effect of the anthelmintic Mebendazole on Cysticercus cellulosae maintained in culture medium was studied by transmission electron microscopy. In addition to the well-known morphological changes induced by Mebendazole in other cestode and nematode larvae, it also induced the cytoplasmic appearance of paracrystalline bundles in the secretory cells of the bladder wall. These bundles were formed by groups of large parallel tubules arranged in a hexagonal-like pattern. The tubules, which had an external diameter of about 50 nm and a length that might exceed 5 μm, were surrounded by a matrix and a distance between neighbouring tubules of 80–120 nm centre to centre was estimated. The tubules were stable to colchicine and low temperature. The temporary appearance of bundles is described and some alternative explanations on their origin are advanced.

Stress Relaxation Behavior of GH4169 Alloy

2020 ◽  
Vol 1013 ◽  
pp. 52-58
Author(s):  
Xu Dong Lu ◽  
Song Yi Shi ◽  
Bo Wen ◽  
Ya Wei Zhang ◽  
Jin Hui Du
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Stress Relaxation ◽  
Initial Stress ◽  
Relaxation Behavior ◽  
Stress Relaxation Behavior ◽  
Transmission Electron ◽  
Microscopy Techniques ◽  
The Relationship ◽  
Gh4169 Alloy

The relaxation properties of GH4169 alloy were studied contrastively at temperatures ranging from 600 oC to 700 °C and initial stress ranging from 550 MPa to 850 MPa. The relationship between the microstructure and relaxation behavior was evaluated using transmission electron microscopy techniques. It was found that the relaxation limit and relaxation stability of the alloy decreased obviously with the increase of temperature. Further investigations show that the relaxation behavior is mainly depend on both precipitate characteristics and its interaction with dislocations. The alloy with higher strength lever has more excellent stress relaxation stability, because of the inhibition of a large number subgrains on dislocations motion.

The Starting Members of the Series Pr4n+2(C2)nBr5n+5 (n = 1, 2, 3)

2009 ◽  
Vol 64 (8) ◽  
pp. 922-928 ◽  
Author(s):  
Manuel Christian Schaloske ◽  
Hansjürgen Mattausch ◽  
Viola Duppel ◽  
Lorenz Kienle ◽  
Arndt Simon
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Single Crystals ◽  
Lattice Parameters ◽  
Space Group ◽  
X Ray ◽  
Transmission Electron ◽  
General Series ◽  
Microscopy Techniques

The compounds Pr6(C2)Br10, Pr10(C2)2Br15 and Pr14(C2)3Br20 were prepared from PrBr3 and the appropriate amounts of Pr and C and characterized by X-ray structure analyses of single crystals. All three compounds crystallize in space group P1 with lattice parameters a = 7.571(2), b = 9.004(2), c = 9.062(2) Å ,α = 108.57(3), β = 97.77(3), γ = 106.28(3)◦ for Pr6(C2)Br10; a = 9.098(2), b = 10.127(2), c = 10.965(2) A° , α = 70.38(3), β = 66.31(3), γ = 70.84(3)◦ for Pr10(C2)2Br15; a = 9.054(2), b = 10.935(2), c = 13.352(3) Å , α = 86.27(3), β = 72.57(3), γ = 66.88(3)◦ for Pr14(C2)3Br20. They are members of a general series Ln4n+2(C2)nBr5n+5 and isostructural with the corresponding iodides known for Ln = La, Ce, Pr. Pr6(C2)Br10 was further characterized via transmission electron microscopy techniques

Regenerated Middle Ear Mucosa after Tympanoplasty. Part I. Transmission Electron Microscopy

1986 ◽  
Vol 94 (3) ◽  
pp. 339-343 ◽  
Author(s):  
Roberto Gamoletti ◽  
Paola Poggi ◽  
Mario Sanna ◽  
Carlo Zini
Keyword(s):  
Electron Microscopy ◽  
Middle Ear ◽  
Goblet Cells ◽  
Secretory Cells ◽  
Canal Wall ◽  
Ciliated Cells ◽  
Middle Ear Mucosa ◽  
Morphologic Characteristics ◽  
Transmission Electron ◽  
Ultrastructural Appearance

The ultrastructural appearance of the regenerated middle ear mucosa—found at the second operation of staged intact canal wall tympanoplasty (ICWT) with mastoidectomy—has been evaluated with the transmission electron microscope. The regenerated epithelium showed all the morphologic characteristics of the normal middle ear mucosa: ciliated cells, noncillated cells, and secretory cells. All of these (Including goblet cells) have been found in the specimens. It is concluded that a normal middle ear mucosa regenerates to cover all denuded bone surfaces after the first operation of staged ICWT with mastoidectomy, when silicone rubber sheeting has been used to prevent adhesions and maintain an air-containing middle ear space.

The Creation and Annealing of Heavy Ion Damage in Silicon

1987 ◽  
Vol 93 ◽  
Author(s):  
L. M. Howe ◽  
M. H. Rainville
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Spatial Distribution ◽  
High Resolution ◽  
Heavy Ion ◽  
High Energy ◽  
Transmission Electron ◽  
Ion Damage ◽  
Deposited Energy ◽  
Microscopy Techniques

ABSTRACTHigh resolution transmission electron microscopy techniques have been used to obtain information on the contrast, spatial distribution, size and annealing behaviour of the damaged regions produced within individual collision cascades by heavy ion (As, Sb and Bi) bombardment (10–120 KeV) of silicon with 1.0 × 1011 – 6.0 × 1011 ions cm−2. The fraction of the theoretical cascade volume occupied by a heavily damaged region steadily increased as the average deposited energy density within the cascade increased. At high energy densities, the visible damage produced in the main cascade consisted of a single, isolated damaged region. With decreasing values of (i.e. increasing ion implant energies), there was an increasing tendency for multiple damaged regions to be produced within the main cascade.

scholarly journals Scanning Microscopy Techniques as an Assessment Tool of Materials and Interventions for the Protection of Built Cultural Heritage

Scanning ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-20 ◽  
Author(s):  
Antonia Moropoulou ◽  
Elisabetta Zendri ◽  
Pilar Ortiz ◽  
Ekaterini T. Delegou ◽  
Ioanna Ntoutsi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Assessment Tool ◽  
Scanning Microscopy ◽  
Spectroscopy Analysis ◽  
Built Heritage ◽  
Research Areas ◽  
Transmission Electron ◽  
Microscopy Techniques ◽  
Scanning Electron

Scanning microscopy techniques have emerged as powerful scientific tools for analysing materials of architectural or archaeological interest, since the commercialization of the first scanning electron microscopy instrumentation in the early 60s. This study is aimed at reviewing and highlighting the significance of several scanning microscopy techniques employed in the protection of built heritage. The diffusion of scanning electron microscopy with energy-dispersive X-ray spectroscopy analysis (SEM-EDX) is proven to be the widest among the available scanning microscopy techniques, while transmission electron microscopy (TEM) applications are steadily present in the field of built heritage protection. The building material characterization, the weathering mechanism investigation, and the development of compatible and performing conservation materials are some major research areas where the application of the aforementioned techniques is discussed. The range of techniques, along with aspects of instrumentation and sample preparation are, also, considered.

Role of Electron Microscopy in Semiconductor Electronic Defects Analysis

1985 ◽  
Vol 46 ◽  
Author(s):  
P. M. Petroff
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Transmission Electron ◽  
Semiconductor Electronic ◽  
Scanning Transmission ◽  
Electronic Defect ◽  
Defects Analysis ◽  
Microscopy Techniques ◽  
Electronic Defects

AbstractA review of the Transmission Electron Microscopy and Scanning Transmission Electron Microscopy techniques used for electronic defect identification is presented. The structural, chemical and STEM based spectroscopy methods for electronic defect analysis are discussed along with selected examples.

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