Use of electron microscopy to characterize the surfaces of flocculent and nonflocculent yeast cells

The surfaces of flocculent and nonflocculent yeast cells have been examined by electron microscopy. Nonextractive preparative procedures for scanning electron microscopy allow comparison in which sharp or softened images of surface details (scars, etc.) are the criteria for relative abundance of flocculum material. Asexually flocculent budding-yeast cells cannot be distinguished from nonflocculent budding-yeast cells in scanning electron micrographs because the scar details of both are well resolved, being hard and sharp. On the other hand, flocculent fission-yeast cells are readily distinguished from nonflocculent cells because fission scars are mostly soft or obscured on flocculent cells, but sharp on nonflocculent cells. Sexually and asexually flocculent fission-yeast cells cannot be distinguished from one another as both are heavily clad in "mucilaginous" or "hairy" coverings. Examination of lightly extracted and heavily extracted flocculent fission-yeast cells by transmission electron microscopy provides micrographs consistent with the scanning electron micrographs.Key words: flocculation, budding yeast, fission yeast, scanning, transmission.

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Development of 200 kV Scanning-Transmission Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052067 ◽

1974 ◽

Vol 32 ◽

pp. 410-411

Author(s):

H. Koike ◽

S. Sakurai ◽

K. Ueno ◽

M. Watanabe

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Scanning Transmission Electron Microscope ◽

The Other ◽

Morphological Observation ◽

Magnetic Domains ◽

Transmission Electron ◽

Scanning Transmission ◽

Backscattered Electron ◽

Increasing Demand

In recent years, there has been increasing demand for higher voltage SEMs, in the field of surface observation, especially that of magnetic domains, dislocations, and electron channeling patterns by backscattered electron microscopy. On the other hand, the resolution of the CTEM has now reached 1 ∼ 2Å, and several reports have recently been made on the observation of atom images, indicating that the ultimate goal of morphological observation has beem nearly achieved.

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Pollen morphology of Sabinaria magnifica (Cryosophileae, Coryphoideae, Arecaceae)

Phytotaxa ◽

10.11646/phytotaxa.207.1.9 ◽

2015 ◽

Vol 207 (1) ◽

pp. 135 ◽

Cited By ~ 1

Author(s):

Giovanni Raul Bogota ◽

Carina Hoorn ◽

Wim Star ◽

Rob Langelaan ◽

Hannah Banks ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Light Microscopy ◽

Pollen Morphology ◽

Pollen Grains ◽

The Other ◽

Transmission Electron ◽

Palm Species ◽

Scanning Electron

Sabinaria magnifica is so far the only known species in the recently discovered tropical palm genus Sabinaria (Arecaceae). Here we present a complete description of the pollen morphology of this palm species based on light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). We also made SEM-based comparisons of Sabinaria with other genera within the tribe Cryosophileae. Pollen grains of Sabinaria magnifica resemble the other genera in the heteropolar, slightly asymmetric monads, and the monosulcate and tectate exine with perforate surface. Nevertheless, there are some clear differences with Thrinax, Chelyocarpus and Cryosophila in terms of aperture and exine. S. magnifica differs from its closest relative, Itaya amicorum, in the exine structure. This study shows that a combination of microscope techniques is essential for the identification of different genera within the Cryosophileae and may also be a necessary when working with other palynologically less distinct palm genera.

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An Inexpensive Approach for Bright-Field and Dark-Field Imaging by Scanning Transmission Electron Microscopy in Scanning Electron Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927613014049 ◽

2014 ◽

Vol 20 (1) ◽

pp. 124-132 ◽

Cited By ~ 6

Author(s):

Binay Patel ◽

Masashi Watanabe

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Lattice Spacing ◽

Dark Field ◽

Bright Field ◽

Specimen Holder ◽

Transmission Electron ◽

Scanning Transmission ◽

Scanning Electron

AbstractScanning transmission electron microscopy in scanning electron microscopy (STEM-in-SEM) is a convenient technique for soft materials characterization. Various specimen-holder geometries and detector arrangements have been used for bright-field (BF) STEM-in-SEM imaging. In this study, to further the characterization potential of STEM-IN-SEM, a new specimen holder has been developed to facilitate direct detection of BF signals and indirect detection of dark-field (DF) signals without the need for substantial instrument modification. DF imaging is conducted with the use of a gold (Au)-coated copper (Cu) plate attached to the specimen holder which directs highly scattered transmitted electrons to an off-axis yttrium-aluminum-garnet (YAG) detector. A hole in the copper plate allows for BF imaging with a transmission electron (TE) detector. The inclusion of an Au-coated Cu plate enhanced DF signal intensity. Experiments validating the acquisition of true DF signals revealed that atomic number (Z) contrast may be achieved for materials with large lattice spacing. However, materials with small lattice spacing still exhibit diffraction contrast effects in this approach. The calculated theoretical fine probe size is 1.8 nm. At 30 kV, in this indirect approach, DF spatial resolution is limited to 3.2 nm as confirmed experimentally.

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Scanning electron microscopy in diagnostic pathology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110738 ◽

1984 ◽

Vol 42 ◽

pp. 82-85

Author(s):

S. Siew

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

The Other ◽

Secondary Electrons ◽

Diagnostic Pathology ◽

Backscattered Electrons ◽

Transmission Electron ◽

Stereoscopic Rendering ◽

Scanning Electron

Scanning electron microscopy (SEM) is a newcomer into the field of microscopy but it has made tremendous strides in the two decades since its inception. In its evolution, it has progressed from an esoteric instrument to its application as a diagnostic tool. SEM has certain attributes which make it a desirable, if not essential, complement to the other, more established, modes of microscopy - light - (LM) and transmission electron microscopy (TEM). By means of its ability to collect secondary electrons generated from the surface of a specimen exposed to the electron beam, SEM registers a stereoscopic rendering of the field examined. This basic principle is comparable to that of direct vision, where the image is formed by the generation of secondary photons from an object exposed to a beam of light. Hence, the highly descriptive term “microvision” has been applied to SEM. SEM has the capacity to collect backscattered electrons (BEI).

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High-resolution scanning electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100127244 ◽

1987 ◽

Vol 45 ◽

pp. 530-533

Author(s):

T. Nagatani

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

High Resolution ◽

Field Emission ◽

Scanning Transmission Electron Microscope ◽

Objective Lens ◽

Second Development ◽

Transmission Electron ◽

Scanning Transmission ◽

Scanning Electron

Although the main development of scanning electron microscopy (SEM) has been accomplished mostly by the Cambridge group and it has not been changed so much for about two decades, it should be noted that there have been two important developments to pursuing high resolution of better than 1nm.Most notably, use of a field emission gun developed by Crewe et al for the scanning transmission electron microscope (STEM) to form a fine electron beam has been most effective in SEMs due to its high brightness and low energy spread. Thus, several models of field emission (FE) SEMs have been developed in the early ’70s and commercialized with a resolution of 2∼3nm at around 30kV.The second development is to use a highly excited objective lens. The specimen has to be set inside the pole-pieces (so-called “in-lens” type).

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STEM (Scanning Transmission Electron Microscopy) in a SEM (Scanning Electron Microscope) for Failure Analysis and Metrology

ISTFA 2002: Conference Proceedings from the 28th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2002p0077 ◽

2002 ◽

Author(s):

William E. Vanderlinde

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Material Structure ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Scanning Electron ◽

Thin Samples

Abstract Recent developments in transmission electron microscopy (TEM) sample preparation have greatly reduced the time and cost for preparing thin samples. In this paper, a method is demonstrated for viewing thin samples in transmission in an unmodified scanning electron microscope (SEM) using an easily constructed sample holder. Although not a substitute for true TEM analysis, this method allows for spatial resolution that is superior to typical SEM imaging and provides image contrast from material structure that is typical of TEM images. Furthermore, the method can produce extremely high resolution x-ray maps that are typically produced only by scanning transmission electron microscope (STEM) systems.

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Electron Tomography of HEK293T Cells Using Scanning Electron Microscope–Based Scanning Transmission Electron Microscopy

Microscopy and Microanalysis ◽

10.1017/s1431927612001158 ◽

2012 ◽

Vol 18 (5) ◽

pp. 1037-1042 ◽

Cited By ~ 1

Author(s):

Yun-Wen You ◽

Hsun-Yun Chang ◽

Hua-Yang Liao ◽

Wei-Lun Kao ◽

Guo-Ji Yen ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Scanning Transmission Electron Microscopy ◽

Electron Tomography ◽

Transmission Electron ◽

Scanning Transmission ◽

3D Volume ◽

Scanning Electron

AbstractBased on a scanning electron microscope operated at 30 kV with a homemade specimen holder and a multiangle solid-state detector behind the sample, low-kV scanning transmission electron microscopy (STEM) is presented with subsequent electron tomography for three-dimensional (3D) volume structure. Because of the low acceleration voltage, the stronger electron-atom scattering leads to a stronger contrast in the resulting image than standard TEM, especially for light elements. Furthermore, the low-kV STEM yields less radiation damage to the specimen, hence the structure can be preserved. In this work, two-dimensional STEM images of a 1-μm-thick cell section with projection angles between ±50° were collected, and the 3D volume structure was reconstructed using the simultaneous iterative reconstructive technique algorithm with the TomoJ plugin for ImageJ, which are both public domain software. Furthermore, the cross-sectional structure was obtained with the Volume Viewer plugin in ImageJ. Although the tilting angle is constrained and limits the resulting structural resolution, slicing the reconstructed volume generated the depth profile of the thick specimen with sufficient resolution to examine cellular uptake of Au nanoparticles, and the final position of these nanoparticles inside the cell was imaged.

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Spatial Resolution in Scanning Electron Microscopy and Scanning Transmission Electron Microscopy Without a Specimen Vacuum Chamber

Microscopy and Microanalysis ◽

10.1017/s1431927616011405 ◽

2016 ◽

Vol 22 (4) ◽

pp. 754-767 ◽

Cited By ~ 3

Author(s):

Kayla X. Nguyen ◽

Megan E. Holtz ◽

Justin Richmond-Decker ◽

David A. Muller

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Scanning Transmission Electron Microscopy ◽

Vacuum Chamber ◽

Operating Conditions ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Scanning Electron

AbstractA long-standing goal of electron microscopy has been the high-resolution characterization of specimens in their native environment. However, electron optics require high vacuum to maintain an unscattered and focused probe, a challenge for specimens requiring atmospheric or liquid environments. Here, we use an electron-transparent window at the base of a scanning electron microscope’s objective lens to separate column vacuum from the specimen, enabling imaging under ambient conditions, without a specimen vacuum chamber. We demonstrate in-air imaging of specimens at nanoscale resolution using backscattered scanning electron microscopy (airSEM) and scanning transmission electron microscopy. We explore resolution and contrast using Monte Carlo simulations and analytical models. We find that nanometer-scale resolution can be obtained at gas path lengths up to 400 μm, although contrast drops with increasing gas path length. As the electron-transparent window scatters considerably more than gas at our operating conditions, we observe that the densities and thicknesses of the electron-transparent window are the dominant limiting factors for image contrast at lower operating voltages. By enabling a variety of detector configurations, the airSEM is applicable to a wide range of environmental experiments including the imaging of hydrated biological specimens and in situ chemical and electrochemical processes.

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