Cryo-scanning electron microscopy (CSEM) in the advancement of functional plant biology: energy dispersive X-ray microanalysis (CEDX) applications

2010 ◽  
Vol 37 (11) ◽  
pp. 1011 ◽  
Author(s):  
Margaret E. McCully ◽  
Martin J. Canny ◽  
Cheng X. Huang ◽  
Celia Miller ◽  
Frank Brink
Keyword(s):  
Single Cells ◽  
Energy Dispersive ◽  
Intercellular Spaces ◽  
Root Pressure ◽  
Solute Content ◽  
X Ray ◽  
Plant Parts ◽  
Specific Analysis ◽  
Vesicular Arbuscular

The capacity to make measurements of elemental concentrations at the level of single cells by energy dispersive X-ray microanalysis of cryo-fixed, inherently-hydrated plant parts (CEDX) is changing or extending our understanding of many plant functions. We include in this review a wide-ranging catalogue of studies that have used CEDX which provides access to the literature on elements measured, plants and tissues studied, techniques used, level of quantitation and the significant findings. These findings include new perspectives on the following areas: salt tolerance; xylem maturation and solute content, root pressure and embolism refilling; the contents of intercellular spaces; sequestration of toxic elements; biomineralisation with silicon; movement of tracer homologues of native cations; indirect localisation of molecules with a distinctive element component; transfer of nutrients from vesicular-arbuscular (VA) mycorrhizas; the role of mucilages in protection and in generating mechanical force. In an Appendix we discuss the procedures involved in CEDX: cryo-fixation, specimen planing, etching, elemental quantitation and mapping. Limitations on sample numbers, elements measurable, spatial resolution, sensitivity and threshold concentrations quantifiable are outlined. A brief discussion of the potential of emerging technologies for cell-specific analysis of cryo-fixed, hydrated specimens is included. In the Accessory Publication we list our standard protocol for CEDX.

scholarly journals Evaluation of Trace Elements in Thyroid Adenomas Using Energy Dispersive X-Ray Fluorescent Analysis

2021 ◽  
pp. 1-7
Author(s):  
Vladimir Zaichick ◽  
Keyword(s):  
Trace Elements ◽  
Exploratory Study ◽  
Thyroid Tissue ◽  
Energy Dispersive ◽  
Benign Tumors ◽  
Tissue Samples ◽  
X Ray ◽  
Fluorescent Analysis ◽  
Thyroid Adenomas

Thyroid adenomas (TA) are benign tumors, but there is a 20% possibility of malignant transformation. The distinguishing between the TA and thyroid cancer (TC) is tricky, therefore new TA biomarkers are needed. Furthermore, the role of trace elements (TE) in etiology and pathogenesis of TA is unclear. The aim of this exploratory study was to examine the content of bromine (Br), cooper (Cu), iron (Fe), rubidium (Rb), strontium (Sr), and zinc (Zn) in the normal and in adenomatous thyroid. Thyroid tissue levels of six TE were prospectively evaluated in 19 patients with TA and 105 healthy inhabitants. Measurements were performed using 109Cd radionuclide-induced energy-dispersive X-ray fluorescent analysis Tissue samples were divided into two portions. One was used for morphological study while the other was intended for TE analysis. It was found that contents of Br and Cu were significantly higher (25.8 and 4.16 times, respectively) and content of Sr were significantly lower (39%) in adenomatous thyroid in comparison with normal level. There are considerable changes in TE contents in the adenomatous thyroid.

Electron Energy-Loss and Energy Dispersive X-Ray Spectros-Copy Studies of Diffusion Bonded Cu-Al2O3 Interfaces

1997 ◽  
Vol 3 (S2) ◽  
pp. 993-994
Author(s):  
R. Hashimoto ◽  
E. S. K. Menon ◽  
M. Saunders ◽  
A. G. Fox
Keyword(s):  
Grain Boundary ◽  
Energy Loss ◽  
Electron Energy ◽  
Potential Role ◽  
Energy Dispersive ◽  
Commercial Alumina ◽  
X Ray ◽  
Metal Ceramic ◽  
Electron Energy Loss

The metal-ceramic interface between copper and alumina has been studied by TEM, Electron Energy-Loss Spectroscopy (EELS), and Energy Dispersive X-ray spectroscopy (EDX). of partic-ular interest is the potential role of silicon which is the major impurity in commercial alumina. This investigation focuses on the presence and distribution of silicon within the bulk alumina and at the diffusion bonded CU-AI2O3 interface using a Topcon 002B TEM equipped with an EDAX EDX detector and a Gatan Imaging Filter. The interface was created under vacuum by diffusion bonding of 100/xm copper foils (99.999% purity) pressed between polished alumina substrates (∼99.5% purity) for several hours at ∼90% of the melting temperature of the metal.An initial investigation of the bulk AI2O3 indicated that the majority of the Si occurred at the triple points. A typical example is shown in Fig. la. EDX spectra acquired with a 6nm probe from the center of the junction (Fig. lbi) and at the grain boundary indicate that the Si wets the grain boundary to a limited extent.

scholarly journals Potential Role of Hydroxyapatite Nanocrystalline for Early Diagnostics of Ovarian Cancer

Diagnostics ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1741
Author(s):  
Ruslana Chyzhma ◽  
Artem Piddubnyi ◽  
Sergey Danilchenko ◽  
Olha Kravtsova ◽  
Roman Moskalenko
Keyword(s):  
Ovarian Cancer ◽  
Potential Role ◽  
Ovarian Tumors ◽  
Energy Dispersive ◽  
Mineral Component ◽  
Early Diagnostics ◽  
Psammoma Bodies ◽  
X Ray ◽  
Malignant Neoplasia

Calcification is one of the clinical and morphological manifestations of ovarian tumors and it begins at the initial stages of carcinogenesis. Thus, this process can be used for the early diagnostics of some malignant ovarian tumors. We compared the results of ultrasound and histology and found that calcifications of a size less than 200 μm are not detected by ultrasound. These calcified structures are round fragile particles of different sizes. In the EDX (Energy-dispersive X-ray spectroscopy) spectra, the main lines were from Ca and P, and the ratio of these elements corresponds to hydroxyapatite. Thus, we established that hydroxyapatite is the main mineral component of ovarian psammoma bodies and could be used for early diagnostics of ovarian malignant neoplasia.

Microanalysis of precipitates in a ferritic steel

1978 ◽  
Vol 36 (1) ◽  
pp. 618-619
Author(s):  
J.M. Titchmarsh
Keyword(s):  
Ferritic Steel ◽  
Particle Identification ◽  
Energy Dispersive ◽  
Objective Lens ◽  
Ferritic Steels ◽  
Replica Technique ◽  
X Ray ◽  
Large Numbers ◽  
Scanning Transmission ◽  
Made In

The advances in recent years in the microanalytical capabilities of conventional TEM's fitted with probe forming lenses allow much more detailed investigations to be made of the microstructures of complex alloys, such as ferritic steels, than have been possible previously. In particular, the identification of individual precipitate particles with dimensions of a few tens of nanometers in alloys containing high densities of several chemically and crystallographically different precipitate types is feasible. The aim of the investigation described in this paper was to establish a method which allowed individual particle identification to be made in a few seconds so that large numbers of particles could be examined in a few hours.A Philips EM400 microscope, fitted with the scanning transmission (STEM) objective lens pole-pieces and an EDAX energy dispersive X-ray analyser, was used at 120 kV with a thermal W hairpin filament. The precipitates examined were extracted using a standard C replica technique from specimens of a 2¼Cr-lMo ferritic steel in a quenched and tempered condition.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

Energy Dispersive X-Ray Measurements of thin Metal Foils

1976 ◽  
Vol 34 ◽  
pp. 426-427
Author(s):  
J. Bentley ◽  
E. A. Kenik
Keyword(s):  
Materials Science ◽  
Energy Dispersive Spectrometer ◽  
Thin Foil ◽  
Thin Metal ◽  
Energy Dispersive ◽  
Thin Specimen ◽  
X Ray ◽  
Metal Foils ◽  
Small Probe ◽  
Scanning Transmission

Instruments combining a 100 kV transmission electron microscope (TEM) with scanning transmission (STEM), secondary electron (SEM) and x-ray energy dispersive spectrometer (EDS) attachments to give analytical capabilities are becoming increasingly available and useful. Some typical applications in the field of materials science which make use of the small probe size and thin specimen geometry are the chemical analysis of small precipitates contained within a thin foil and the measurement of chemical concentration profiles near microstructural features such as grain boundaries, point defect clusters, dislocations, or precipitates. Quantitative x-ray analysis of bulk samples using EDS on a conventional SEM is reasonably well established, but much less work has been performed on thin metal foils using the higher accelerating voltages available in TEM based instruments.

The role of silicon in forages: A quantitative X-Ray study

1987 ◽  
Vol 45 ◽  
pp. 416-417
Author(s):  
Janet H. Woodward ◽  
D. E. Akin
Keyword(s):  
Sodium Acetate ◽  
Dry Matter ◽  
Acetate Buffer ◽  
Plant Tissues ◽  
Sodium Acetate Buffer ◽  
X Ray ◽  
Dry Matter Digestibility ◽  
Percent Composition

Silicon (Si) is distributed throughout plant tissues, but its role in forages has not been clarified. Although Si has been suggested as an antiquality factor which limits the digestibility of structural carbohydrates, other research indicates that its presence in plants does not affect digestibility. We employed x-ray microanalysis to evaluate Si as an antiquality factor at specific sites of two cultivars of bermuda grass (Cynodon dactvlon (L.) Pers.). “Coastal” and “Tifton-78” were chosen for this study because previous work in our lab has shown that, although these two grasses are similar ultrastructurally, they differ in in vitro dry matter digestibility and in percent composition of Si.Two millimeter leaf sections of Tifton-7 8 (Tift-7 8) and Coastal (CBG) were incubated for 72 hr in 2.5% (w/v) cellulase in 0.05 M sodium acetate buffer, pH 5.0. For controls, sections were incubated in the sodium acetate buffer or were not treated.

Sign in / Sign up

Export Citation Format

Share Document