scholarly journals High resolution scanning electron microscopy of isolated and in situ cytoskeletal elements.

1979 ◽  
Vol 83 (1) ◽  
pp. 249-254 ◽  
Author(s):  
W Ip ◽  
D A Fischman
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Intermediate Filaments ◽  
Actin Filaments ◽  
Critical Point Drying ◽  
Osmium Impregnation ◽  
Cytoskeletal Elements ◽  
Scanning Electron

Evidence is presented that cytoskeletal structures (actin filaments, intermediate filaments, and microtubules) can be resolved by scanning electron microscopy after osmium impregnation of biological material, using thiocarbohydrazide as a ligand, followed by critical-point drying. These different classes of filaments or tubules can be identified both as purified protein polymers and as structured organelles within cryofractured or detergent-extracted cells.

High-Resolution Resistance Mapping in SEM

2018 ◽  
Author(s):  
Grigore Moldovan ◽  
Wolfgang Joachimi ◽  
Guillaume Boetsch ◽  
Jörg Jatzkowski ◽  
Frank Altman
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Reference Structure ◽  
Total Resistance ◽  
Embedded Electronics ◽  
Improved Performance ◽  
Mapping Techniques ◽  
Scanning Electron

Abstract This work presents advanced resistance mapping techniques based on Scanning Electron Microscopy (SEM) with nanoprobing systems and the related embedded electronics. Focus is placed on recent advances to reduce noise and increase speed, such as integration of dedicated in situ electronics into the nanoprobing platform, as well as an important transition from current-sensitive to voltagesensitive amplification. We show that it is now possible to record resistance maps with a resistance sensitivity in the 10W range, even when the total resistance of the mapped structures is in the range of 100W. A reference structure is used to illustrate the improved performance, and a lowresistance failure case is presented as an example of analysis made possible by these developments.

High-Resolution Field Emission Scanning Electron Microscopy (FESEM) Imaging of Cellulose Microfibril Organization in Plant Primary Cell Walls

2017 ◽  
Vol 23 (5) ◽  
pp. 1048-1054 ◽  
Author(s):  
Yunzhen Zheng ◽  
Daniel J. Cosgrove ◽  
Gang Ning
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cell Wall ◽  
High Resolution ◽  
Field Emission ◽  
Cell Walls ◽  
Cellulose Microfibrils ◽  
Critical Point Drying ◽  
Sputter Coating ◽  
Scanning Electron

AbstractWe have used field emission scanning electron microscopy (FESEM) to study the high-resolution organization of cellulose microfibrils in onion epidermal cell walls. We frequently found that conventional “rule of thumb” conditions for imaging of biological samples did not yield high-resolution images of cellulose organization and often resulted in artifacts or distortions of cell wall structure. Here we detail our method of one-step fixation and dehydration with 100% ethanol, followed by critical point drying, ultrathin iridium (Ir) sputter coating (3 s), and FESEM imaging at a moderate accelerating voltage (10 kV) with an In-lens detector. We compare results obtained with our improved protocol with images obtained with samples processed by conventional aldehyde fixation, graded dehydration, sputter coating with Au, Au/Pd, or carbon, and low-voltage FESEM imaging. The results demonstrated that our protocol is simpler, causes little artifact, and is more suitable for high-resolution imaging of cell wall cellulose microfibrils whereas such imaging is very challenging by conventional methods.

High-resolution scanning electron microscopy of human metaphase chromosomes

1982 ◽  
Vol 56 (1) ◽  
pp. 409-422 ◽  
Author(s):  
C.J. Harrison ◽  
T.D. Allen ◽  
M. Britch ◽  
R. Harris
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Three Dimensional ◽  
Loop Model ◽  
Giemsa Banding ◽  
Metaphase Chromosomes ◽  
Osmium Impregnation ◽  
Chromosome Integrity ◽  
Scanning Electron

Human metaphase chromosomes, prepared for light microscopy were examined by scanning electron microscopy. Use of an osmium impregnation technique eliminated the need for sputter-coating and allowed high-resolution visualization of uncoated specimens. Chromosomes were of three-dimensional cylindrical profile, with well-defined chromatids and centromeres. Prior to Giemsa-banding a smooth surface morphology was observed. Relaxation of chromosome integrity by Giemsa-banding pretreatment allowed resolution of several orders of chromosome structure not previously demonstrated by scanning electron microscopy. The observed organization of the chromatin fibres allowed parallels to be drawn with the radial loop model of chromosome construction as described by Marsden and Laemmli.

Cryo-scanning Electron Microscopy of reovirus structure

1994 ◽  
Vol 52 ◽  
pp. 134-135
Author(s):  
Ya Chen ◽  
Victoria E. Centonze ◽  
Max L. Nibert ◽  
Gary Borisy
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Actin Filaments ◽  
Molecular Basis ◽  
Protein Components ◽  
Cryo Scanning Electron Microscopy ◽  
Scanning Electron

The introduction of the "in lens" type field emission gun has revolutionized SEM technology. Usingtest specimens, it has been shown that it is now possible to achieve nanometer resolution with the advantages of cryotechniques. Topographical views similar to replicas can also be obtained without having to remove biological material prior to microscopical inspection. Using these techniques we have been able to image the 5.5nm subunit repeat and the 37nm cross-over repeat of actin filaments in vitro and in situ and the 4nm repeat of tubulin subunits in both axonemal microtubules and in vitro polymerized microtubules. We are currently using cryo-SEM to study the reoviruses. Reoviruses are large,nonenveloped viruses with segmented RNA genomes. Understanding the molecular basis of reovirus pathogenesis requires characterization of the structure of reovirus particles and protein components through which they interact with cells early in infection. Recent cryo-TEM studies on reovirus characterized 3 particle forms - virions, ISVPs, and cores - at ≤ 3 nm resolution.

Scanning electron microscopy: a direct method of identifying pollen grains on moths (Noctuidae: Lepidoptera)

1978 ◽  
Vol 56 (9) ◽  
pp. 2050-2054 ◽  
Author(s):  
W. J. Turnock ◽  
J. Chong ◽  
B. Luit
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Direct Method ◽  
Pollen Grains ◽  
Scanning Electron Micrographs ◽  
Simple Method ◽  
Critical Point Drying ◽  
A Direct Method ◽  
Scanning Electron

A simple method of using scanning electron microscopy to observe pollen grains in situ on feral moths (Noctuidae) is described. This method does not require freeze drying, critical point drying, or any chemical fixation procedures to prepare the specimens for scanning. Pollen grains were found mainly on the proboscises of the moths and can be identified directly from the scanning electron micrographs, thus expediting the study of moth–plant relations.

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