Aluminium Distribution in Freeze-Dried Roots of Cabbage, Lettuce and Kikuyu Grass by Energy-Dispersive X-Ray Analysis

1980 ◽  
Vol 7 (1) ◽  
pp. 101 ◽  
Author(s):  
DO Huett ◽  
RC Menary

The aluminium distribution in transverse sections of fractured and freeze-dried roots of cabbage, lettuce and kikuyu grass was studied by energy-dispersive X-ray analysis. The mean ratios of the integrated counts corresponding to Kα emission spectra for aluminium, phosphorus and silicon were recorded between aluminium and control treatments over three experiments. Peak-to-back- ground ratios (PA/B) were calculated and the aluminium ratios corrected for variations in the corresponding total silicon ratios. Aluminium was found to be uniformly distributed along roots of the three species. The highest peaks (PA) and peak-to-background ratios, suggesting higher concentrations, were recorded in the epidermis followed by the cortex. Aluminium was recorded in the stele of all species and in the protoplasm of cortical cells, with smaller amounts in the protoplasm of xylem parenchyma cells for lettuce and kikuyu grass. The distribution of aluminium supports the hypothesis that its entry to the stele can be achieved by transport both into meristematic cells and the symplasm via the cortex and hence bypassing the barrier at the endodermis. The latter evidence was supported by the presence of aluminium in the radial wall (and cytoplasm) of the endodermis for each species. There was a poor correlation between the distribution of aluminium and phosphorus.

1979 ◽  
Vol 42 (04) ◽  
pp. 1073-1114 ◽  

SummaryIn collaborative experiments in 199 laboratories, nine commercial thromboplastins, four thromboplastins held by the National Institute for Biological Standards and Control (NIBS & C), London and the British Comparative Thromboplastin were tested on fresh normal and coumarin plasmas, and on three series of freeze-dried plasmas. One of these was made from coumarin plasmas and the other two were prepared from normal plasmas; in each series, one plasma was normal and the other two represented different degrees of coumarin defect.Each thromboplastin was calibrated against NIBS&C rabbit brain 70/178, from the slope of the line joining the origin to the point of intersection of the mean ratios of coumarin/normal prothrombin times when the ratios obtained with the two thromboplastins on the same fresh plasmas were plotted against each other. From previous evidence, the slopes were calculated which would have been obtained against the NIBS&C “research standard” thromboplastin 67/40, and termed the “calibration constant” of each thromboplastin. Values obtained from the freeze-dried coumarin plasmas gave generally similar results to those from fresh plasmas for all thromboplastins, whereas values from the artificial plasmas agreed with those from fresh plasmas only when similar thromboplastins were being compared.Taking into account the slopes of the calibration lines and the variation between laboratories, precision in obtaining a patient’s prothrombin time was similar for all thromboplastins.


1986 ◽  
Vol 83 (1) ◽  
pp. 77-87 ◽  
Author(s):  
M.D. Kendall ◽  
A. Warley

Mast cell granules were examined by fully quantitative X-ray microanalysis of 20 cells in freeze-dried cryosections. The mast cells were situated mainly in the connective tissue of the thymic capsule of five adult male Carworth Sprague Europe rats. In addition 30 red blood cells were analysed from the same sections. Nineteen of the mast cells had granules rich in S and K. One cell had smaller granules, and in this cell the granules contained high [Ca] and [P] instead of high [S] and [K]. In the majority of cells (13) the S:K ratio was highly correlated and less than 2.2, whereas in the remaining six cells the individual granule ratios were very variable in any one cell and much higher. The mean granule [K] (994 +/− 57 mmol kg-1 dry wt) was about four times the mean cytoplasmic level of 227 +/− 81 mmol kg-1 dry wt. The existence of this difference in concentration between the granules and the cytoplasm suggests that the K in the granules must be bound. The relationship between the [K] and [S] is discussed with regard to the possible binding of heparin and amines in the granules.


2016 ◽  
Vol 59 (2) ◽  
pp. 198-201
Author(s):  
V. P. Gavrilenko ◽  
A. V. Zablotskii ◽  
S. A. Korneichuk ◽  
A. Yu. Kuzin ◽  
T. A. Kupriyanova ◽  
...  

1980 ◽  
Vol 112 (6) ◽  
pp. 609-614 ◽  
Author(s):  
W. J. Turnock ◽  
G. H. Gerber ◽  
D. U. Sabourin

AbstractSamples of the bodies and elytra of Entomoscelis americana Brown were analyzed separately by X-ray energy-dispersive spectroscopy. Discriminant analysis revealed that the chemoprints of the bodies of newly-emerged beetles (1 wk old) were distinct from those of post-aestivation beetles (9- to 10-wk old). However, the chemoprints of the elytra of newly-emerged and post-aestivation beetles were not as different as those of the bodies as demonstrated by the overlap in the plot of the first two canonical variables. The variances of the mean difference of individual variables between newly-emerged and post-aestivation groups generally were smaller for elytra than for bodies. This suggests that the chemoprints of the elytra of E. americana are more stable than those of the bodies and consequently the elytra should be more suitable than the bodies in insect dispersal studies utilizing the X-ray energy-dispersive spectroscopy technique.


1971 ◽  
Vol 15 ◽  
pp. 197-208
Author(s):  
Hubert K. Chow

Energy dispersive x-ray analysis has become an extremely useful analytical tool. The technique provides for the direct observation of x-ray emission spectra, eliminating the need for a dispersive crystal. The purpose of this reported investigation was to study the use of the technique with a simple pulse height analyzing system and to develop a routine method for correcting Interferences due to adjacent element spectral overlap and matrix effects.The analyzing system consists of a radioisotope source, a lithium drifted silicon detector, a preamplifier, an amplifier, two single channel analyzers and two digital ratemeters. In order to obtain results suitable for quantative measurement, a two-step empirical method was employed for the correction of peak overlapping and matrix effects. If two peaks in a spectrum overlap at their tails, one can set up a channel width of the analyzer to a region where there are no overlapping pulses. It is then possible to calibrate the ratio of the intensity obtained from this channel to that obtained from the whole peak in its pure state, i.e. without the appearance of a neighbor peak. The actual intensity of the peak in the overlapping spectrum is, therefore, the observed counts multiplied by the ratio. The next step is the correction of matrix effect by means of conventional empirical methods using standard samples. Two types of the samples, Zn-Cu powder mixtures and Ee-Cu in aqueous solutions, were studied to illustrate this method. The usefulness of applying the analyzing system and technique to industrial measurements, either on-line or batch, will also be discussed.


1983 ◽  
Vol 63 (4) ◽  
pp. 1071-1074 ◽  
Author(s):  
J. CHONG ◽  
S. T. ALI-KHAN ◽  
B. B. CHUBEY ◽  
G. H. GUBBELS

An energy dispersive X-ray (EDX) analytical method was used to study the freeze-dried powder of seeds of field peas (Pisum sativum L.) with good and poor cooking quality. EDX analysis of the electron-dense particles in the freeze-dried powder revealed the presence of high concentrations of Mg, P, and K, suggesting that the particles were protein bodies. Seeds with different cooking quality were compared with respect to the ratios of these elements in the dense particles. Statistical analysis indicated a significant correlation between these ratios and cooking quality.Key words: Pisum sativum, protein bodies, elemental analysis


1978 ◽  
Vol 56 (19) ◽  
pp. 2408-2414 ◽  
Author(s):  
J. N. A. Lott ◽  
J. S. Greenwood ◽  
C. M. Vollmer

This study was undertaken to discover what elemental losses, if any, were occurring from globoid crystals in seed protein bodies during glutaraldehyde – osmium tetroxide fixation. Unfixed cotyledon and radicle tissue of Cucurbita maxima seed, or tissue after glutaral–dehyde–OsO4 treatment, was quick frozen in liquid N2, ground with a cold mortar and pestle, and low-temperature freeze-dried. Globoid crystals in the freeze-dried powder were subjected to energy dispersive x-ray (EDX) analysis. OsO4 fixation resulted in a major loss of P, Mg, and K from cotyledon globoid crystals and a major loss of P, Mg, K, and Ca from radicle globoid crystals. Despite the loss of elements, the OsO4-fixed globoid crystals were still electron dense. When globoid crystals from glutaraldehyde-fixed, dehydrated, and embedded cotyledon tissue were compared with globoid crystals from glutaraldehyde–OsO4-fixed, dehydrated, and embedded tissue, some extraction was found. The degree of extraction varied from complete loss of P, K, and Mg to loss of K only.Effects of glutaraldehyde–OsO4 fixation upon elemental composition of globoid crystals in several other species was also determined. Brazil nut (Bertholletia excelsa) radicle tissue or cotyledon tissue from walnut (Juglans regia), hazelnut (Corylus avellana), sunflower (Helianthus annuus), golden everlasting daisy (Helichrysum bracteatum), cashew (Anacardium occidentale), pistachio (Pistacia vera), and the Western Australian red-capped gum (Eucalyptus erythrocorys) were fixed either in glutaraldehyde or in glutaraldehyde–OsO4. In these species, EDX analysis of globoid crystal sections showed that OsO4 fixation results in major loss of Mg, K, and Ca. Generally, phosphorus levels were reduced from control values as well. When carrying out EDX analysis studies of globoid crystals, we recommend (1) avoiding any use of OsO4, (2) keeping all fixation, washing, and dehydration times as short as possible, and (3) checking all observations with freeze-dried powders.


Author(s):  
Yusuf I. Koleleni ◽  
Seriver Tafisa

Wavelength dispersive x-ray fluorescence (WDXRF) spectrometer was used to analyze heavy metal concentration in soils and vegetables. The soil and vegetable samples were randomly collected from Minjingu village of Manyara region in Tanzania. The results indicate the soils to be contaminated with heavy metals with mean concentrations of 53±0.4 For Mn, 40±0.2 for Sr, 2059±4.2 for Fe, 760±2.7 for Al, 12±0.3 for Cs and 4±0.04 for Ni in mg/kg which was above the Maximum Tolerable Limits (MTLs). Except Cl was below MDL. While vegetables recorded the mean concentrations of 60±1.2 for Mn, 68±0.1 for Sr, 620±2.36 for Fe, 284±1,13 for Al, 56±0.5 for Cs, 13±0.1 for Ni and 714±0.7 for Cl in mg/kg. The reference and experimental results of soil and vegetables revealed that the optimized machine has given the best results, where the experimental data was very close to the reference values The reference material of soil 7 and International Atomic Energy Agency (IAEA) 395 for vegetables shows the deviation of less than 2%.The Minimum Detection Limit (MDL) for vegetables and soil of the WDXRF spectrometer was obtained under low back ground for different matrix effects. There were high correlation coefficient of heavy metals in soils and vegetables at 99% level. The findings indicate that Minjingu soils and grown vegetables were highly contaminated with heavy metals mainly from soils and polluted air, at levels able to pose detrimental health effects to the consumers. Thus need of regular monitoring of the grown vegetables around phosphate mines is recommended.


Sign in / Sign up

Export Citation Format

Share Document