A study of Cs-137 spatial distribution in soil thin sections by digital autoradiography and microscopy

2014 ◽  
Vol 142 ◽  
pp. 94-100 ◽  
Author(s):  
E.M. Korobova ◽  
N.N. Dogadkin ◽  
A.A. Shiryaev ◽  
V.P. Kolotov ◽  
N.N. Kononkova ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Thin Sections ◽  
Digital Autoradiography

scholarly journals Spatial control of carbon dynamics in soil by microbial decomposer communities

2020 ◽  
Author(s):  
Holger Pagel ◽  
Björn Kriesche ◽  
Marie Uksa ◽  
Christian Poll ◽  
Ellen Kandeler ◽  
...  
Keyword(s):  
Organic Matter ◽  
Spatial Distribution ◽  
Soil Organic Matter ◽  
Distribution Patterns ◽  
Microbial Succession ◽  
Thin Sections ◽  
Spatial Control ◽  
Soil Organic Matter Turnover ◽  
Microbial Decomposer ◽  
Modelling Approach

<p>Trait-based models have improved the understanding and prediction of soil organic matter dynamics in terrestrial ecosystems. Microscopic observations and pore scale models are now increasingly used to quantify and elucidate the effects of soil heterogeneity on microbial processes. Combining both approaches provides a promising way to accurately capture spatial microbial-physicochemical interactions and to predict overall system behavior. The present study aims to quantify controls on carbon (C) turnover in soil due to the mm-scale spatial distribution of microbial decomposer communities in soil. A new spatially explicit trait-based model (SpatC) has been developed that captures the combined dynamics of microbes and soil organic matter (SOM) by taking into account microbial life-history traits and SOM accessibility. Samples of spatial distributions of microbes at µm-scale resolution were generated using a spatial statistical model based on Log Gaussian Cox Processes which was originally used to analyze distributions of bacterial cells in soil thin sections. These µm-scale distribution patterns were then aggregated to derive distributions of microorganisms at mm-scale. We performed Monte-Carlo simulations with microbial distributions that differ in mm-scale spatial heterogeneity and functional community composition (oligotrophs, copiotrophs and copiotrophic cheaters). Our modelling approach revealed that the spatial distribution of soil microorganisms triggers spatiotemporal patterns of C utilization and microbial succession. Only strong spatial clustering of decomposer communities induces a diffusion limitation of the substrate supply on the microhabitat scale, which significantly reduces the total decomposition of C compounds and the overall microbial growth. However, decomposer communities act as functionally redundant microbial guilds with only slight changes in C utilization. The combined statistical and process-based modelling approach derives distribution patterns of microorganisms at the mm-scale from microbial biogeography at microhabitat scale (µm) and quantifies the emergent macroscopic (cm) microbial and C dynamics. Thus, it effectively links observable process dynamics to the spatial control by microbial communities. Our study highlights a powerful approach that can provide further insights into the biological control of soil organic matter turnover.</p>

Mapping 241Am Spatial Distribution Within Anatomical Bone Structures Using Digital Autoradiography

2019 ◽  
Vol 117 (2) ◽  
pp. 179-186 ◽  
Author(s):  
George Tabatadze ◽  
Brian W. Miller ◽  
Sergei Y. Tolmachev
Keyword(s):  
Spatial Distribution ◽  
Digital Autoradiography ◽  
Bone Structures

scholarly journals Mapping c-axis fabrics to study physical processes in ice

1995 ◽  
Vol 41 (137) ◽  
pp. 197-203 ◽  
Author(s):  
R. B. Alley ◽  
A.J. Gow ◽  
D.A. Meese
Keyword(s):  
Grain Size ◽  
Spatial Distribution ◽  
Ice Core ◽  
West Antarctica ◽  
Physical Processes ◽  
Thin Sections ◽  
Additional Information ◽  
Average Grain Size ◽  
Scatter Plots

AbstractMapping the spatial distribution of c-axis orientations in ice thin sections is not much more difficult than preparing c-axis scatter plots but can reveal additional information about processes responsible for the observed fabric and texture of the ice. Distributions of angles between c axes of neighboring grains from the Byrd Station (West Antarctica) ice core suggest that polygonization causes average grain-size to stabilize below 400 m depth.

scholarly journals Mapping c-axis fabrics to study physical processes in ice

1995 ◽  
Vol 41 (137) ◽  
pp. 197-203 ◽  
Author(s):  
R. B. Alley ◽  
A.J. Gow ◽  
D.A. Meese
Keyword(s):  
Grain Size ◽  
Spatial Distribution ◽  
Ice Core ◽  
West Antarctica ◽  
Physical Processes ◽  
Thin Sections ◽  
Additional Information ◽  
Average Grain Size ◽  
Scatter Plots

AbstractMapping the spatial distribution ofc-axis orientations in ice thin sections is not much more difficult than preparingc-axis scatter plots but can reveal additional information about processes responsible for the observed fabric and texture of the ice. Distributions of angles betweencaxes of neighboring grains from the Byrd Station (West Antarctica) ice core suggest that polygonization causes average grain-size to stabilize below 400 m depth.

Spatial distribution prediction of pre-Sinian volcanic and metamorphic rocks in Xinhenan-Sandaoqiao area, Northern Tarim Basin

2021 ◽  
pp. 1-49
Author(s):  
Pengyuan Han ◽  
Xindong Diao ◽  
Wenlong Ding ◽  
Liyuan Zang ◽  
Qingxiu Meng ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Distribution Pattern ◽  
Seismic Reflection ◽  
Metamorphic Rock ◽  
Oil And Gas ◽  
Thermal Contact ◽  
Intrusive Rock ◽  
Metamorphic Rocks ◽  
Thin Sections ◽  
Reflection Characteristics

The main type of oil and gas reservoir in the Xinhenan-Sandaoqiao area is buried hills. The distribution pattern and scale of reservoirs are obviously controlled by pre-Sinian basement strata. However, the lithologic combination and spatial distribution pattern of pre-Sinian basement in this area are still unclear. In this paper, the spatial distribution of pre-Sinian basement volcanic and metamorphic rocks is studied by using the method of multifactor comprehensive analysis. Firstly, the lithology and lithologic combination of igneous and metamorphic rocks are determined according to cores and thin sections. Guided by the seismic reflection characteristics of different lithologic combinations, different lithologic combinations are identified on the profile by combining the seismic reflection characteristics of single well and multiwell. Secondly, using cluster analysis technology, three seismic attributes sensitive to lithology are selected from 10 attributes, crossplots of three seismic attribute values are constructed, and the distribution range of attribute values corresponding to different lithologic combinations is defined for plane lithologic identification. Finally, the plane lithology distribution of the surface layer of pre-Sinian basement is described by combining plane and profile. Six distribution types were identified: deep metamorphic bedrock area in Kuqu depression, dynamic mixed metamorphic rock and intermediate-acidic intrusive rock area, metamorphic bedrock in thrust napple slopes area, thermal contact metamorphic rock area, intermediate-acidic intrusive rock area, dynamic metamorphic rock area and gneiss area in faulted uplift core.

scholarly journals Mapping 238U decay chain equilibrium state in thin sections of geo-materials by digital autoradiography and microprobe analysis

2018 ◽  
Vol 140 ◽  
pp. 228-237 ◽  
Author(s):  
Axel Angileri ◽  
Paul Sardini ◽  
Jérôme Donnard ◽  
Samuel Duval ◽  
Hugo Lefeuvre ◽  
...  
Keyword(s):  
Equilibrium State ◽  
Microprobe Analysis ◽  
Decay Chain ◽  
Thin Sections ◽  
Digital Autoradiography

Ultrastructure of the Parotid Gland of the Nine-Banded Armadillo

1977 ◽  
Vol 35 ◽  
pp. 640-641
Author(s):  
J. R. Ruby
Keyword(s):  
Endoplasmic Reticulum ◽  
Parotid Gland ◽  
Periodic Acid ◽  
Acinar Cells ◽  
Duct System ◽  
Parotid Glands ◽  
Dasypus Novemcinctus ◽  
Anterior Portion ◽  
Periodic Acid Schiff ◽  
Thin Sections

Parotid glands were obtained from five adult (four male and one female) armadillos (Dasypus novemcinctus) which were perfusion-fixed. The glands were located in a position similar to that of most mammals. They extended interiorly to the anterior portion of the submandibular gland.In the light microscope, it was noted that the acini were relatively small and stained strongly positive with the periodic acid-Schiff (PAS) and alcian blue techniques, confirming the earlier results of Shackleford (1). Based on these qualities and other structural criteria, these cells have been classified as seromucous (2). The duct system was well developed. There were numerous intercalated ducts and intralobular striated ducts. The striated duct cells contained large amounts of PAS-positive substance.Thin sections revealed that the acinar cells were pyramidal in shape and contained a basally placed, slightly flattened nucleus (Fig. 1). The rough endoplasmic reticulum was also at the base of the cell.

Three-Dimensional Reconstruction Using Stereo Pairs from Serial Thick Sections

1977 ◽  
Vol 35 ◽  
pp. 562-563
Author(s):  
Robert Glaeser ◽  
Thomas Bauer ◽  
David Grano
Keyword(s):  
Three Dimensional ◽  
Dimensional Structure ◽  
Serial Sections ◽  
Thin Sections ◽  
3 Dimensional ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Dimensional Reconstruction ◽  
Stereo Imagery ◽  
Whole Mounts

In transmission electron microscopy, the 3-dimensional structure of an object is usually obtained in one of two ways. For objects which can be included in one specimen, as for example with elements included in freeze- dried whole mounts and examined with a high voltage microscope, stereo pairs can be obtained which exhibit the 3-D structure of the element. For objects which can not be included in one specimen, the 3-D shape is obtained by reconstruction from serial sections. However, without stereo imagery, only detail which remains constant within the thickness of the section can be used in the reconstruction; consequently, the choice is between a low resolution reconstruction using a few thick sections and a better resolution reconstruction using many thin sections, generally a tedious chore. This paper describes an approach to 3-D reconstruction which uses stereo images of serial thick sections to reconstruct an object including detail which changes within the depth of an individual thick section.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

Lead aspartate: a new en bloc stain for electron microscopy

1978 ◽  
Vol 36 (2) ◽  
pp. 34-35
Author(s):  
J.R. Walton
Keyword(s):  
Electron Microscopy ◽  
Calcium Ion ◽  
Enzyme Reaction ◽  
Lead Citrate ◽  
Reaction Products ◽  
En Bloc ◽  
Thin Sections ◽  
Lead Salts ◽  
Thin Sectioning ◽  
High Alkalinity

In electron microscopy, lead is the metal most widely used for enhancing specimen contrast. Lead citrate requires a pH of 12 to stain thin sections of epoxy-embedded material rapidly and intensively. However, this high alkalinity tends to leach out enzyme reaction products, making lead citrate unsuitable for many cytochemical studies. Substitution of the chelator aspartate for citrate allows staining to be carried out at pH 6 or 7 without apparent effect on cytochemical products. Moreover, due to the low, controlled level of free lead ions, contamination-free staining can be carried out en bloc, prior to dehydration and embedding. En bloc use of lead aspartate permits the grid-staining step to be bypassed, allowing samples to be examined immediately after thin-sectioning.Procedures. To prevent precipitation of lead salts, double- or glass-distilled H20 used in the stain and rinses should be boiled to drive off carbon dioxide and glassware should be carefully rinsed to remove any persisting traces of calcium ion.

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