Super-Thin Serial Sectioning for High-Resolution 3-D Reconstruction of Cellular Structures

We are developing techniques for obtaining the thinnest possible serial sections of biological specimens. Our goal is to produce not just an occasional very thin section but large numbers of 5-15 nm serial sections suitable for 3-D reconstruction. We have worked out conditions that allow us routinely to cut serial sections ˜15 nm thick, and have achieved ribbons of sections with an average thickness of only 11 nm.We have worked with the Leica Ultracut S and Ultracut UCT microtomes, which have proven to be exceptionally stable instruments, capable of very regular advance between cutting strokes. The resulting low variability in section thickness is essential for serial sections thinner than 15 nm. However, these machines have an inherent forward drift that increases the thickness of sections cut soon after a block has been mounted and prepared for cutting. This drift is initially 50-100 nm/min, but decreases to only 10-20 nm/min if the microtome is allowed to cycle for 0.5—1.5 hours.

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Internal compartmentation of the mitochondrion: An HVEM tomographic study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125063 ◽

1992 ◽

Vol 50 (1) ◽

pp. 932-933

Author(s):

Michael Marko ◽

Ardean Leith ◽

Bruce McEwen ◽

Joachim Frank ◽

Carmen Mannella

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Thin Section ◽

Serial Sectioning ◽

Inner Membrane ◽

Considerable Uncertainty ◽

Outer Membranes ◽

Thin Section Electron Microscopy ◽

Section Electron ◽

Section Electron Microscopy

Much of what is known about the internal organization of the mitochondrion has been inferred from thin-section electron microscopy. This work has shown this organelle to have two membranes (outer and inner) and a matrix (the area bounded by the inner membrane), but there is considerable uncertainty about the 3D shape of the cristae (the infoldings of the inner membrane) and the nature of the contacts between the inner and outer membranes. Attempts to reconstruct the mitochondrion’s interior by serial sectioning have failed because the required resolution (5-10 nm) cannot be practically achieved in the z-direction. The only 3D views provided until now have come from high-resolution SEM of freeze-cleaved and metal-shadowed mitochondria.

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The ultrastructure of the double membrane-bound bodies and endoplasmic reticulum in serial sections of wheat spot mosaic-affected wheat plants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161023 ◽

1990 ◽

Vol 48 (3) ◽

pp. 694-695

Author(s):

M. H. Chen ◽

C. Hiruki

Keyword(s):

Endoplasmic Reticulum ◽

High Resolution ◽

Membrane Structure ◽

Mosaic Disease ◽

Serial Sections ◽

Thin Sections ◽

Double Membrane ◽

Southern Alberta ◽

Membrane Bound ◽

Scanning Em

Wheat spot mosaic disease was first discovered in southern Alberta, Canada, in 1956. A hitherto unidentified disease-causing agent, transmitted by the eriophyid mite, caused chlorosis, stunting and finally severe necrosis resulting in the death of the affected plants. Double membrane-bound bodies (DMBB), 0.1-0.2 μm in diameter were found to be associated with the disease.Young tissues of leaf and root from 4-wk-old infected wheat plants were fixed, dehydrated, and embedded in Spurr’s resin. Serial sections were collected on slot copper grids and stained. The thin sections were then examined with a Hitachi H-7000 TEM at 75 kV. The membrane structure of the DMBBs was studied by numbering them individually and tracing along the sections to see any physical connection with endoplasmic reticulum (ER) membranes. For high resolution scanning EM, a modification of Tanaka’s method was used. The specimens were examined with a Hitachi Model S-570 SEM in its high resolution mode at 20 kV.

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A metal- coating Chamber for High-Resolution Cryo-SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180847 ◽

1990 ◽

Vol 48 (1) ◽

pp. 418-419

Author(s):

John G. Sheehan

Keyword(s):

High Resolution ◽

Colloidal Suspensions ◽

Metal Coating ◽

Colloidal Interactions ◽

Amorphous Ice ◽

High Vapor ◽

Particulate Coatings ◽

20 Nm ◽

Film Nucleation ◽

Coating Chamber

Improvements in particulate coatings for printable paper require understanding mechanisms of colloidal interactions in paper coating suspensions. One way to deduce colloidal interactions is to mage particle spacings and orientations at high resolution with cryo-SEM. Recent improvements in cryo-SEM technique have increased resolution enough to image particles in coating paints,vhich are sometimes smaller than 100 nm. In this report, a metal-coating chamber is described for preparation of colloidal suspensions for cryo-SEM at resolution down to 20 nm. It was found that etching is not necessary to achieve this resolution.A 120 K cryo-SEM sample will remain in an SEM for hours without noticeable condensation of imorphous ice. This is due to the high vapor pressure of vapor-condensed amorphous ice, measured by Kouchi. However, clean vacuum is required to coat samples with the thinnest possible continuous metal films which are required for high magnification SEM. Vapor contaminants, especially hrydrocarbons, are known to interfere with thin-film nucleation and growth so that more metal is needed to form continuous films, and resolution is decreased. That is why the metal-coating chamber in fig. 1 is designed for the cleanest possible vacuum. Feedthroughs for the manipulator md the shutter, which are operated during metal coating, are sealed with leak-proof stainless-steel Dellows. The transfer rod slides through a baseplate feedthrough that is double o-ring sealed.

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Computed Tomographic Discography in the Evaluation of Extreme Lateral Disc Herniation

Neurosurgery ◽

10.1097/00006123-198403000-00018 ◽

1984 ◽

Vol 14 (3) ◽

pp. 350-352 ◽

Cited By ~ 1

Author(s):

J. C. Angtuaco Edgardo ◽

C. Holder John ◽

C. Boop Warren ◽

F. Binet Eugene

Keyword(s):

Lumbar Spine ◽

High Resolution ◽

Contrast Enhancement ◽

Thin Section ◽

Preoperative Evaluation ◽

Intervertebral Discs ◽

Ct Scans ◽

Computed Tomographic ◽

Disc Herniations ◽

Lateral Disc Herniation

Abstract Thin section, high resolution computed tomographic (CT) scans of the lumbar spine produce images that can show herniated intervertebral discs without intravenous or intrathecal contrast enhancement. With this technique, the diagnosis of posterolateral and midline herniation has been greatly facilitated. This communication reports the use of CT discography in the preoperative evaluation of two patients who were shown at discography and proven at operation to have extreme lateral disc herniations.

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Cryogenic vitrification and 3D serial sectioning using high resolution cryo-FIB SEM technology for brine-filled grain boundaries in halite: first results

Geofluids ◽

10.1111/j.1468-8123.2007.00205.x ◽

2008 ◽

Vol 8 (1) ◽

pp. 60-72 ◽

Cited By ~ 41

Author(s):

G. DESBOIS ◽

J. L. URAI ◽

C. BURKHARDT ◽

M. R. DRURY ◽

M. HAYLES ◽

...

Keyword(s):

High Resolution ◽

Grain Boundaries ◽

Serial Sectioning ◽

First Results

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Influence of Interfacial Copper on the Ti-SiO2 Reaction During Nitridation of Cu-Ti Films

MRS Proceedings ◽

10.1557/proc-398-631 ◽

1995 ◽

Vol 398 ◽

Author(s):

Daniel Adams ◽

T.L. Alford ◽

N.D. Theodore ◽

T. Laursen ◽

S.W. Russell ◽

...

Keyword(s):

Free Surface ◽

High Resolution ◽

Consumption Rate ◽

Catalytic Effect ◽

Energy Dispersive ◽

Ti Alloy ◽

Alloy Films ◽

X Ray ◽

20 Nm ◽

Ti Films

ABSTRACTCu(90 nm)/Ti(20 nm) bilayers and Cu(Ti 27 at.%) alloy films were deposited on SiO2 and annealed in an NH3 ambient at temperatures 400–700° C for 30 min. During annealing Ti segregated to both the free surface and the alloy/SiO2 interface. At the surface Ti reacted with NH3 to form TiN, whereas at the interface the Ti reacted with the SiO2 to form a TiO/Ti5Si3 structure. High resolution energy dispersive x-ray analysis revealed the presence of interfacial Cu between the Ti-silicide and Ti-oxide layers at temperatures greater than 450°C. Using Cu-Ti alloy films enhanced the Si02 consumption rate by a factor of 3-4 compared to that of pure Ti. It is suggested that the interfacial Cu is responsible for the increased rate. It is plausible that an interfacial Cu2O component has a catalytic effect on the Ti- SiO2 reaction.

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High resolution simulations of energy absorption in dynamically loaded cellular structures

Shock Waves ◽

10.1007/s00193-016-0651-2 ◽

2016 ◽

Vol 27 (2) ◽

pp. 221-236 ◽

Cited By ~ 3

Author(s):

R. E. Winter ◽

M. Cotton ◽

E. J. Harris ◽

D. E. Eakins ◽

G. McShane

Keyword(s):

High Resolution ◽

Energy Absorption ◽

Cellular Structures ◽

Dynamically Loaded

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Two-Scale Topology Optimization With Parameterized Cellular Structures

10.1115/detc2021-71980 ◽

2021 ◽

Author(s):

Sina Rastegarzadeh ◽

Jun Wang ◽

Jida Huang

Keyword(s):

Topology Optimization ◽

High Resolution ◽

Structural Optimization ◽

Optimization Problem ◽

Material Design ◽

Homogenization Method ◽

Elasticity Tensor ◽

Structure Design ◽

Cellular Structures ◽

Mapping Technique

Abstract Advances in additive manufacturing enable the fabrication of complex structures with intricate geometric details. It also escalates the potential for high-resolution structure design. However, the increasingly finer design brings computational challenges for structural optimization approaches such as topology optimization (TO) since the number of variables to optimize increases with the resolutions. To address this issue, two-scale TO paves an avenue for high-resolution structural design. The design domain is first discretized to a coarse scale, and the material property distribution is optimized, then using micro-structures to fill each property field. In this paper, instead of finding optimal properties of two scales separately, we reformulate the two-scale TO problem and optimize the design variables concurrently in both scales. By introducing parameterized periodic cellular structures, the minimal surface level-parameter is defined as the material design parameter and is implemented directly in the optimization problem. A numerical homogenization method is employed to calculate the elasticity tensor of the cellular materials. The stiffness matrices of the cellular structures derived as a function of the level parameters, using the homogenization results. An additional constraint on the level parameter is introduced in the structural optimization framework to enhance adjacent cellulars interfaces’ compatibility. Based on the parameterized micro-structure, the optimization problem is solved concurrently with an iterative solver. The reliability of the proposed approach has been validated with different engineering design cases. Numerical results show a noticeable increase in structure stiffness using the level parameter directly in the optimization problem than the state-of-art mapping technique.

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