An Inverse Relation Between Cell Density and the Number of Microvilli in Cultures of BHK 21 Hamster Fibroblasts

1970 ◽  
Vol 7 (3) ◽  
pp. 695-709
Author(s):  
C. H. O'NEILL ◽  
E. A. C. FOLLETT
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Monolayer Culture ◽  
Cell Contact ◽  
Inverse Relation ◽  
Culture Density ◽  
Microscope Technique ◽  
The Relationship ◽  
Number Of Cells ◽  
Scanning Electron

The relationship between culture density and the number of microvilli on the cell surface has been studied using BHK21 cells in established monolayer culture. The number of microvilli can be estimated quantitatively by a scanning electron-microscope technique. It can be increased by applying specific antiserum, but whether antibody is applied or not a significant number of cells regularly bear microvilli. This number is characteristic of the culture density. In sparse cultures above a certain minimum density it is relatively high, and in confluent cultures it is much reduced. These results indicate that microvilli may be inhibited by cell contact.

The Effect of Surface Finish on Zinc Whisker Growth

2012 ◽  
Vol 472-475 ◽  
pp. 2756-2759
Author(s):  
Wen Cui ◽  
Shao Jun Qi
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Surface Finish ◽  
Whisker Growth ◽  
Experimental Conditions ◽  
Steel Substrates ◽  
The Relationship ◽  
Rough Surface Finish ◽  
Scanning Electron ◽  
Effect Of Surface

To understand the relationship between surface finish and zinc whisker growth, this study investigated the growth of whiskers on two mild steel substrates of different surface finish by Field Emission Gun Scanning Electron Microscope (FEG SEM). Results show that, under the same experimental conditions, deposits on substrates with a mirror finish grew less whiskers and nodules than substrates with a rough surface finish.

scholarly journals Biometrics of the sporangia and spores of the Parablechnum cordatum complex (Blechnaceae, Polypodiopsida)

2021 ◽  
Vol 45 ◽  
pp. e73655
Author(s):  
Aleksandra Patrjcia Wal ◽  
Sonia Molino ◽  
Antonio Murciano ◽  
Carmen Prada ◽  
José María Gabriel y Galán
Keyword(s):  
Electron Microscope ◽  
Discriminant Analysis ◽  
Scanning Electron Microscope ◽  
Analysis Of Variance ◽  
Pacific Region ◽  
Taxonomic Significance ◽  
Biometric Analysis ◽  
Equatorial Diameter ◽  
Number Of Cells ◽  
Scanning Electron

Parablechnum is the most diverse genus of Blechnaceae (ca. 65 species), with a pantropical distribution and two centers of diversity, in America and in the Austro-Pacific region. The species are dimorphic, with often erect rhizomes and rhizomatic scales, 1-pinnate fronds, with truncate blade at base, conform apex and stalked pinnae. This group presents many taxonomic problems, needing more detailed studies to resolve these conflicts of separation between species. This work deals with the American complex of P. cordatum in which the species P. cordatum, P. schiedeanum, P. chilense, P. falciforme and Blechnum varians are included. A biometric analysis of sporangia and spores, important taxonomic structures in the distinction of ferns, has been carried out. The data were subjected to a one-way analysis of variance and a discriminant analysis. In addition, the spores were observed under a scanning electron microscope to study their ornamentation. Of the characters we have studied thickness of the arcus, number of cells in the arcus, number of cells in the hypostome and major equatorial diameter of the spore have statisticalParablechnum is the most diverse genus of Blechnaceae (ca. 65 species), with a pantropical distribution and two centers of diversity, in America and in the Austro-Pacific region. The species are dimorphic, with often erect rhizomes and rhizomatic scales, 1-pinnate fronds, with truncate blade at base, conform apex and stalked pinnae. This group presents many taxonomic problems, needing more detailed studies to resolve these conflicts of separation between species. This work deals with the American complex of P. cordatum in which the species P. cordatum, P. schiedeanum, P. chilense, P. falciforme and Blechnum varians are included. A biometric analysis of sporangia and spores, important taxonomic structures in the distinction of ferns, has been carried out. The data were subjected to a one-way analysis of variance and a discriminant analysis. In addition, the spores were observed under a scanning electron microscope to study their ornamentation. Of the characters we have studied thickness of the arcus, number of cells in the arcus, number of cells in the hypostome and major equatorial diameter of the spore have statistically supported taxonomic significance and are therefore useful for species separation.  

scholarly journals Palyno-morphology of Hedera L. (The ivy genus, araliaceae) and their systematics implications

Genetika ◽  
2021 ◽  
Vol 53 (2) ◽  
pp. 851-865
Author(s):  
Fahimeh Fallah ◽  
Farrokh Ghahremaninejad
Keyword(s):  
Grain Size ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Pollen Grains ◽  
Pollen Grain ◽  
Hedera Helix ◽  
Transmission Electron ◽  
Pollen Grain Size ◽  
The Relationship ◽  
Scanning Electron

The palynomorphological characteristics of 5 species belonging to Hedera of the Araliaceae family were studied in detail. These plant species were collected from various phytogeographical regions of Iran and Hungary. The palynological investigation was accomplished using Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM). Pollen grains of the species are reticulate, prolate, sub-prolate, tricolporate, isopolar, radially symmetrical, and monad. The largest pollen grain was in the Hedera colchica species (72.24?1.6 ?m) and the smallest pollen grain was in Hedera helix (28.63?2.1 ?m). The research carried out by the TEM showed that the species were different in terms of exine thickness, tectum thickness, foot layer thickness, the diameter and length of the Columella, the thickness and shape of the Caput, the tectum to foot layer )T/F( ratio, the absence or presence of the Endexine and the thickness of the Intine layers. The main purpose of this study was the importance of the relationship between pollen grain size and the number of chromosomes and ploidy level in Hedera species.

scholarly journals A high-yield technique for preparing cells fixed in suspension for scanning electron microscopy.

1975 ◽  
Vol 67 (2) ◽  
pp. 476-480 ◽  
Author(s):  
S K Sanders ◽  
E L Alexander ◽  
R C Braylan
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Quantitative Comparison ◽  
High Yield ◽  
Live Cells ◽  
A Cell ◽  
Number Of Cells ◽  
Scanning Electron

Human leukocytes fixed in suspension were allowed to settle onto poly-L-lysine-coated glass coverslips and prepared for observation with the scanning electron microscope (SEM). The coverslips were dehydrated in ethanol, critical point dried with CO2, and coated with gold-palladium. With the aid of a locator grid, several fields were photographed with light microscopy after the cells had settled onto the poly-L-lysine-coated coverslips and again after completion of the processing before SEM observation. Quantitative comparison of the number of cells present after settling with the number retained for final viewing with the SEM revealed a cell yield approaching 100%. This simple, reproducible, high-yield technique for processing cells fixed in suspension for SEM prevents changes in surface architecture induced by collecting live cells onto various substrates before fixation and also avoids potentially selective cell losses. Such a technique should allow quantitative correlations between SEM and other morphological and functional parameters.

Fabrication of Microchannels on SiC Substrate by Femtosecond Laser

2012 ◽  
Vol 557-559 ◽  
pp. 1322-1325 ◽  
Author(s):  
Yi He Li ◽  
Hua Xiao ◽  
Gong Yi Li ◽  
Jian Feng ◽  
Xiao Dong Li
Keyword(s):  
Silicon Carbide ◽  
Electron Microscope ◽  
Laser Pulse ◽  
Scanning Electron Microscope ◽  
Femtosecond Laser ◽  
Optical Microscope ◽  
Pdms Stamp ◽  
The Relationship ◽  
Scanning Electron ◽  
Micro Patterns

A novel femtosecond laser directly writing method was utilized to fabricate microchannels on silicon carbide (SiC) substrate. The micro patterns were transferred to a Polydimethylsiloxane (PDMS) stamp, characterized by both optical microscope and scanning electron microscope (SEM). The relationship between size (depth and width) of channels and power of laser pulse were discussed in detail.

scholarly journals Scanning electron microscope studies of Avena coleoptiles during primary leaf emergence

2014 ◽  
Vol 57 (4) ◽  
pp. 431-445 ◽  
Author(s):  
Norman R. Dollahon ◽  
Andrew B. Maksymowych ◽  
Maria Galanti ◽  
Joseph A. Orkwiszewski
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Vascular Tissue ◽  
Guard Cells ◽  
Primary Leaf ◽  
Scanning Electron Microscope Study ◽  
Leaf Emergence ◽  
The Relationship ◽  
Scanning Electron

A scanning electron microscope study of the fine structure of coleoptiles of <em>Avena sativa</em> L. cv. Clintford has revealed information about the relationship between aspects of coleoptilar structure and the emergence of the primary leaf. Stomata are located on the lateral sides of the coleoptile and arch across the apex. The location of the stomata and associated vascular tissue may play a role in the splitting of the coleoptile pore and influence the manner in which the primary leaf emerges. Details of the surface fine structure of the coleoptile pore, its associated cells, stomata and guard cells are presented.

A Simple Light-Microscope Technique for the Examination of Cell Surfaces

1973 ◽  
Vol 13 (1) ◽  
pp. 317-319
Author(s):  
A. ROSS ◽  
I. P. GORMLEY
Keyword(s):  
Heavy Metal ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Microscopy ◽  
Light Microscope ◽  
Simple Technique ◽  
Cell Surfaces ◽  
Microscope Technique ◽  
Scanning Electron

A simple technique for the examination of cell surfaces by shadowing them with a heavy metal and examining by light microscopy has been described. Stained preparations can be examined and photographed initially prior to investigation by this technique. It is suggested that this technique could be used instead of the scanning electron microscope or replica techniques where the limited resolution of the light microscope is sufficient.

Ultrastructure of conidiogenesis in Scopulariopsis brevicaulis

1971 ◽  
Vol 49 (5) ◽  
pp. 745-755 ◽  
Author(s):  
Garry T. Cole ◽  
H. C. Aldrich
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Scopulariopsis Brevicaulis ◽  
Freeze Etching ◽  
Cytological Changes ◽  
Relationship Of ◽  
The Relationship ◽  
Fungi Imperfecti ◽  
Scanning Electron

An ultrastructural study of conidia and conidiogenous cells of Scopulariopsis brevicaulis (Sacc.) Bain. in various stages of development is presented using transmission and scanning electron microscope and freeze-etching techniques. Septa between both fertile and vegetative cells are examined. The development of the double septum is outlined and mechanisms are suggested to explain conidium secession. Cytological changes which occur in the developing conidium initial are illustrated and their possible association with wall synthesis and deposition is noted. Change in the orientation of rodlets occurs on the walls of frozen-etched conidia at different stages of formation. The relationship of this phenomenon to conidium development is discussed. Description of the nature of wall relations during conidium ontogeny is stressed because of its importance in a classification of Fungi Imperfecti based on developmental characters of the reproductive cells. A diagrammatic interpretation of the sequence of formation of wall layers of the developing conidium is presented.

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