Localisation of aluminium in root apex cells of two Australian perennial grasses by X-ray microanalysis

1998 ◽  
Vol 25 (4) ◽  
pp. 427 ◽  
Author(s):  
Simon A. Crawford ◽  
Alan T. Marshall ◽  
Sabine Wilkens
Keyword(s):  
Significant Positive Correlation ◽  
Root Apex ◽  
Root Cap ◽  
Perennial Grasses ◽  
Elemental Distribution ◽  
X Ray ◽  
Positive Correlation ◽  
Distribution Maps ◽  
Meristematic Cells ◽  
Root Apices

To determine if an increased aluminium (Al) sensitivity is the result of greater accumulation of Al in root apices, the quantity and distribution of Al in root apex cells of Danthonia linkii Kunth and Microlaena stipoides (Labill.) R.Br. was investigated by X-ray microanalysis. Seedlings were grown in nutrient solution with 0, 185 and 370 µM total Al for 24 h after which the terminal 5 mm of the roots were excised, rapidly frozen and embedded using freeze-substitution. Elemental distribution maps of root apices showed that Al had accumulated in the nuclei of root cap and meristematic cells in Al-stressed roots of D. linkii but not in M. stipoides. Al appeared to be co-localised with phosphorous (P) in the nuclei of these cells. Quantitation of Al revealed that Al-stressed root apex cells of D. linkiiaccumulated significantly more Al than M. stipoides. Exposure of D. linkii roots to Al resulted in substantial increases in the P content of root apex cells, and a significant positive correlation was found between Al and P in both root cap and meristematic cells. Analysis of intracellular structures showed that the majority of Al had accumulated in the nuclei of cells. A significant positive correlation was found between Al and P in the nuclei, but not in the cytoplasm or cell walls. No positive correlation was found between Al and P in root apex cells of M. stipoides.

scholarly journals Micro-Fabric Analyzer (MFA): A New Semiautomated ArcGIS-Based Edge Detector for Quantitative Microstructural Analysis of Rock Thin-Sections

2021 ◽  
Vol 10 (2) ◽  
pp. 51 ◽  
Author(s):  
Roberto Visalli ◽  
Gaetano Ortolano ◽  
Gaston Godard ◽  
Rosolino Cirrincione
Keyword(s):  
Physical Properties ◽  
Electron Backscatter Diffraction ◽  
Microstructural Analysis ◽  
Image Features ◽  
Elemental Distribution ◽  
Edge Detector ◽  
Sandstone Sample ◽  
Thin Sections ◽  
X Ray ◽  
Distribution Maps

Micro-Fabric Analyzer (MFA) is a new GIS-based tool for the quantitative extrapolation of rock microstructural features that takes advantage both of the characteristics of the X-ray images and the optical image features. Most of the previously developed edge mineral grain detectors are uniquely based on the physical properties of the X-ray-, electron-, or optical-derived images; not permitting the exploitation of the specific physical properties of each image type at the same time. More advanced techniques, such as 3D microtomography, permit the reconstruction of tridimensional models of mineral fabric arrays, even though adjacent mineral grain boundaries with the same atomic density are often not detectable. Only electron backscatter diffraction (EBSD) allows providing high-performing grain boundary detection that is crystallographically differentiated per mineral phase, even though it is relatively expensive and can be executed only in duly equipped microanalytical laboratories by suitably trained users. Instead, the MFA toolbox allows quantifying fabric parameters subdivided per mineral type starting from a crossed-polarizers high-resolution RGB image, which is useful for identifying the edges of the individual grains characterizing rock fabrics. Then, this image is integrated with a set of micro-X-ray maps, which are useful for the quantitative extrapolation of elemental distribution maps. In addition, all this is achieved by means of low-cost and easy-to-use equipment. We applied the tool on amphibolite, mylonitic-paragneiss, and -tonalite samples to extrapolate the particle fabric on different metamorphic rock types, as well as on the same sandstone sample used for another edge detector, which is useful for comparing the obtained results.

scholarly journals Morphoanatomic changes in shoot and root apices of banana Williams (AAA, Musa sp.) cultured on different N6- benzyladenine concentrations

1969 ◽  
Vol 92 (1-2) ◽  
pp. 53-72
Author(s):  
Maribel Ramírez-Villalobos ◽  
Helga Lindorf ◽  
Eva De García
Keyword(s):  
Lateral Roots ◽  
Root Apex ◽  
Transitional Zone ◽  
Root Cap ◽  
Anatomic Structure ◽  
Musa Sp ◽  
Tunica Layer ◽  
Vitro Development ◽  
Root Apices

Structural evidence about the in vitro growth of the shoot apex (SA) and root apex (RA) of banana is for the most part lacking.This paper presents an analysis of the morphoanatomic events that occur in the in vitro development of the SA, RA and explants of banana Williams cultured under different N6-benzyladenine (BA) concentrations. We examined the SA of explants (8 mm X 1.5 mm, shoot tip with part of rhizome) grown on 0, 2.5 and 5 mg /L of BA for 0, 3, 6, 9 and 12 d, and also the first emergent root (1 to 1.5 cm long) from these explants. Samples were sectioned (10 to 12 µm) and stained with safranin-fast green. The SA showed a dome shape with tunica-corpus organization (a single tunica layer). SA diameters were larger for explants growing in BA (93.75 to 142.05 µm) than in those growing without the cytokinin (73.87 to 85.83 µm), except for the diameter on the sixth day (127.84 µm). The noncultured initial explant without culture reached a diameter of 164.78 µm. The SA showed a cambium-like transitional zone in explants cultured with 2.5 mg/L of BA on the ninth day. This concentration also induced the highest number of shoots per explant (2.19) in 35 days. RA growing in media without BA showed protoderm, ground meristem, procambium, initial cells and root cap whereas with BA procambium, fundamental meristem and root cap (compressed) were distinguished. Benzyladenine decreased the number and length of the roots, inhibited the formation of lateral roots, increased the time for root emergence and caused distortion in their anatomic structure.

scholarly journals Max Ernst’s Woman, Old Man, and Flower (1923–24): Four Paintings in One Revealed by Technical Imaging

Heritage ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 2224-2236
Author(s):  
Ana Martins ◽  
Ellen Davis ◽  
Talia Kwartler
Keyword(s):  
Transitional Period ◽  
Insertion Mutation ◽  
Elemental Distribution ◽  
Technical Literature ◽  
Intermediate Composition ◽  
X Ray ◽  
Distribution Maps ◽  
Final Composition

Examining the painting Woman, Old Man, and Flower (1923–24) by Max Ernst with macro-X-ray fluorescence scanning (MA-XRF), X-ray radiography (XRR) as well as photography under ultraviolet (UVF), infrared reflected (IRR) and transmitted (IRT) illumination revealed the existence and sequence of three distinct paintings concealed under the final composition. The study confirmed a known and previously documented intermediate composition and uncovered two additional states: a very first state exposed by XRR, and a third state revealed in the elemental distribution maps obtained by MA-XRF. The complimentary images document the insertion, mutation, and concealing of several human and anthropomorphic subjects across the four layers, expanding our understanding of the painting and of Ernst’s collage-like pictorial development. In addition, a list of pigments is proposed based on the elemental information provided by MA-XRF, contributing to the technical literature devoted to the materials of Ernst’s paintings during the transitional period between Dada and Surrealism.

Changes in Waterlogged Medieval Window Glass

1988 ◽  
Vol 125 ◽  
Author(s):  
Helen I. Alten
Keyword(s):  
Cross Sections ◽  
Window Glass ◽  
Elemental Distribution ◽  
Air Drying ◽  
X Ray ◽  
Distribution Maps ◽  
Physical Changes

ABSTRACTSamples of wet 13th-14th c. Grisaille window glass, visually sorted according to their extent of corrosion, were examined for physical changes while air-drying and solvent-drying. Polished cross-sections of the samples were examined with a JEOL-35CF SEM with a LINK AN 10,000 dispersive x-ray analyzer. Elemental distribution maps showed distinct alterations in the positioning of elements according to the corroded nature of the glass.

scholarly journals Dual Energy CT Evaluation of the Severity of Pulmonary Thromboembolism: Correlation of Pulmonary Perfusion Score with CT

2020 ◽  
Vol 17 (3) ◽  
Author(s):  
Selen Bayraktaroglu ◽  
Akın Cinkooglu ◽  
Recep Savas ◽  
Naim Ceylan ◽  
Mustafa Bozdağ ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Significant Positive Correlation ◽  
Pulmonary Thromboembolism ◽  
Main Pulmonary Artery ◽  
Dual Energy ◽  
Gas Analysis ◽  
Dual Energy Ct ◽  
Positive Correlation ◽  
Distribution Maps ◽  
Arterial Blood

Background: Pulmonary thromboembolism (PTE) is an important cause of morbidity and mortality in hospitalized patients and computed tomographic angiography (CTA) has become the gold standard diagnostic examination for suspected PTE. Dual energy computed tomography (DECT) not only detects thromboembolic filling defects but also provides functional perfusion information by generating iodine distribution maps. Objectives: The objective of the study is to determine the value of perfusion defect score (P score) in detection of the severity of acute PTE and to correlate it with pulmonary obstruction score (Qanadli score), other CTA parameters and clinical findings. Patients and Methods: Fifty five patients, with acute PTE who underwent DECT were reviewed. We calculated P score, Qanadli score, ratio of the right ventricle diameter to the left ventricle (RV/LV ratio) and the main pulmonary artery (PA) diameter by using the dual energy CTA images. The correlation between CTA parameters and clinical- echocardiographic data was investigated. Results: Correlation analysis showed a significant positive correlation between the P score and Qanadli score (r = 0.748, P < 0.001). There was also a significant positive correlation between P score and RV/LV ratio (r = 0.432, P = 0.001) and between Qanadli score and RV/LV ratio (r = 0.424 P = 0.001). Echocardiographic data was present in 39 patients (70.9 %). P score was significantly higher in patients with RV dilatation (P = 0.022) and RV dysfunction (P = 0.001) on echocardiography. Likewise, similar interaction was present between Qanadli score and RV dilatation (P = 0.023) and RV dysfunction (P = 0.003). No correlation was present between P score and blood gas analysis [partial pressure of oxygen in arterial blood (PaO2), partial pressure of arterial carbon dioxide (PaCO2),(PaO2)/fraction of inspired oxygen (FiO2), oxygen saturation] and hemodynamic data (blood pressure and pulse). Conclusion: P score is seen as a good adjunctive tool to other CTA parameters and echocardiography in detection of PTE severity. Addition of perfusion changes to clinical risk assessment will help in the management of patients.

DEVELOPMENTAL STUDIES ON EUPHORBIA ESULA L.: APICES OF LONG AND SHORT ROOTS

1964 ◽  
Vol 42 (12) ◽  
pp. 1615-1628 ◽  
Author(s):  
M. V. S. Raju ◽  
T. A. Steeves ◽  
J. M. Naylor
Keyword(s):  
Cell Division ◽  
Root Apex ◽  
Root Cap ◽  
Field Conditions ◽  
Euphorbia Esula ◽  
Quiescent Center ◽  
Developmental Studies ◽  
Short Root ◽  
Root Apices ◽  
Root Axis

In both indeterminate long roots and determinate short roots of Euphorbia esula L., the promeristem usually consists of three meristematic layers. One of these represents the stelar pole, the second is continuous with the cortex, and the most distal appears to initiate the root cap – epidermis complex. Variations in this pattern are noted. Autoradiographs of apices of roots supplied with thymidine-H3 under field conditions demonstrate the existence of a region of low nuclear incorporation during a 24 or 48 hour period at the summit of the root axis in long roots. This region corresponds to the quiescent center described by previous authors. Short root apices consistently lack such a region. The pattern of nuclear incorporation of thymidine-H3 suggests that cell division is infrequent or absent in the center of the apex of long roots but not of short roots. Quiescence is thus a phenomenon which is superimposed upon the organization of the root apex in this species, and its presence or absence seems to be related to the developmental potentiality of the root. In many long roots the size of this quiescent region exceeds that of the region which may reasonably be designated the promeristem.

Changes in Waterlogged Medieval Window Glass

1988 ◽  
Vol 123 ◽  
Author(s):  
Helen I. Alten
Keyword(s):  
Cross Sections ◽  
Window Glass ◽  
Elemental Distribution ◽  
Air Drying ◽  
X Ray ◽  
Distribution Maps ◽  
Physical Changes

AbstractSamples of wet 13th-14th c. Grisaille window glass, visually sorted according to their extent of corrosion, were examined for physical changes while air-drying and solvent-drying. Polished cross-sections of the samples were examined with a JEOL-35CF SEM with a LINK AN 10,000 dispersive x-ray analyzer. Elemental distribution maps showed distinct alterations in the positioning of elements according to the corroded nature of the glass.

X-Ray absorption edge elemental imaging of B. thuringienis

1989 ◽  
Vol 47 ◽  
pp. 212-213
Author(s):  
R. L. Stears
Keyword(s):  
Absorption Edge ◽  
Elemental Distribution ◽  
X Rays ◽  
Differential Absorption ◽  
Synchrotron Source ◽  
High Brightness ◽  
X Ray ◽  
Elemental Imaging ◽  
Cellular Integrity ◽  
X Ray Absorption

Because of the nature of the bacterial endospore, little work has been done on analyzing their elemental distribution and composition in the intact, living, hydrated state. The majority of the qualitative analysis entailed intensive disruption and processing of the endospores, which effects their cellular integrity and composition.Absorption edge imaging permits elemental analysis of hydrated, unstained specimens at high resolution. By taking advantage of differential absorption of x-ray photons in regions of varying elemental composition, and using a high brightness, tuneable synchrotron source to obtain monochromatic x-rays, contact x-ray micrographs can be made of unfixed, intact endospores that reveal sites of elemental localization. This study presents new data demonstrating the application of x-ray absorption edge imaging to produce elemental information about nitrogen (N) and calcium (Ca) localization using Bacillus thuringiensis as the test specimen.

Preparation of cultured astrocytes for x-ray microanalysis

1989 ◽  
Vol 47 ◽  
pp. 988-989
Author(s):  
N.K.R. Smith ◽  
K.E. Hunter ◽  
P. Mobley ◽  
L.P. Felpel
Keyword(s):  
Cultured Cells ◽  
Elemental Content ◽  
Elemental Distribution ◽  
Sprague Dawley ◽  
X Ray ◽  
Cultured Astrocytes ◽  
Freeze Dried ◽  
Ultimate Objective

Electron probe energy dispersive x-ray microanalysis (XRMA) offers a powerful tool for the determination of intracellular elemental content of biological tissue. However, preparation of the tissue specimen , particularly excitable central nervous system (CNS) tissue , for XRMA is rather difficult, as dissection of a sample from the intact organism frequently results in artefacts in elemental distribution. To circumvent the problems inherent in the in vivo preparation, we turned to an in vitro preparation of astrocytes grown in tissue culture. However, preparations of in vitro samples offer a new and unique set of problems. Generally, cultured cells, growing in monolayer, must be harvested by either mechanical or enzymatic procedures, resulting in variable degrees of damage to the cells and compromised intracel1ular elemental distribution. The ultimate objective is to process and analyze unperturbed cells. With the objective of sparing others from some of the same efforts, we are reporting the considerable difficulties we have encountered in attempting to prepare astrocytes for XRMA.Tissue cultures of astrocytes from newborn C57 mice or Sprague Dawley rats were prepared and cultured by standard techniques, usually in T25 flasks, except as noted differently on Cytodex beads or on gelatin. After different preparative procedures, all samples were frozen on brass pins in liquid propane, stored in liquid nitrogen, cryosectioned (0.1 μm), freeze dried, and microanalyzed as previously reported.

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