scholarly journals Composite cuticle with heterogeneous layers in the leaf epidermis of Ficus elastica

2019 ◽  
Vol 49 (1) ◽  
Author(s):  
Ki Woo Kim
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Density ◽  
Leaf Epidermis ◽  
Leaf Cuticle ◽  
Transmission Electron

AbstractTwo distinct layers in terms of texture and electron density were observed in the leaf cuticle of Ficus elastica using transmission electron microscopy. As depicted in a model, an inner polysaccharide-rich layer and an outer cutin (or cutan)-rich layer may support the composite, heterogeneous concept of the leaf cuticle.

Effects Of Varying Salinity On Leaf Ultrastructure Of Potamogeton Pectinatus L

1999 ◽  
Vol 5 (S2) ◽  
pp. 1256-1257
Author(s):  
A.D. Barnabas ◽  
P. Bunsi ◽  
Y. Naidoo ◽  
W.J. Przybylowicz ◽  
J. Mesjasz-Przybylowicz
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Salinity ◽  
Ultrastructural Changes ◽  
Potamogeton Pectinatus ◽  
Leaf Epidermis ◽  
Leaf Ultrastructure ◽  
Low Salinity ◽  
Transmission Electron ◽  
Standard Procedures

Potamogeton pectinatus is a submerged halophyte which occurs in waters of low salinity (5% to 10%). Its upper salinity tolerance has been reported to be 19%. Reasons why P.pectinatus is unable to tolerate salinities in excess of 19%is important to our understanding of its biology. In the present study, leaf ultrastructure of plants growing at low salinity was compared with plants growing at high salinity in order to assess the effects of different salinities on the ultrastructure. Attention was focussed on ultrastructural changes occurring in the leaf epidermis, the main photosynthetic tissue.Plants were grown in seawater at two salinities : 5%(low salinity) and 20% (high salinity). Pieces of mature leaf blades from both treatments were harvested and prepared for Transmission Electron Microscopy (TEM) following standard procedures. The overall distribution and concentration of chlorine (CI) in the leaves was ascertained since this element is the most abundant anion in seawater and is important in considerations of salt tolerance in submerged halophytes.

Marginal bands in camel erythrocytes

1979 ◽  
Vol 36 (1) ◽  
pp. 97-107
Author(s):  
W.D. Cohen ◽  
N.B. Terwilliger
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Light Microscopy ◽  
Electron Density ◽  
Electron Micrographs ◽  
Iron Content ◽  
Phase Contrast ◽  
Transmission Electron ◽  
Marginal Band ◽  
Whole Mounts

The elliptical, anucleate erythrocytes of camels have been examined for the presence of marginal bands and their constituent microtubules. Lysis of erythrocytes under microtubule-stabilizing conditions readily revealed marginal bands in at least 3 % of the cells, as observed by phase-contrast and darkfield light microscopy. Microtubules plus a marginal band-encompassing network of material are visible in lysed cell whole mounts with transmission electron microscopy. Marginal band microtubules are also evident in electron micrographs of thin-sectioned camel erythrocytes identifiable as reticuloyctes on the basis of submaximal electron density (reduced haemoglobin iron content) and presence of polysomes. The results suggest that marginal bands may be involved in morphogenesis of camel erythrocytes but are not required for maintenance of their ellipticity after cells are fully differentiated.

scholarly journals Hemagglutination in gill capillaries of sheepshead, Archosargus probatocephalus (Perciformes: Sparidae), infected by a myxosporidean

2022 ◽  
Vol 31 (1) ◽  
Author(s):  
Carlos Azevedo ◽  
Graça Casal ◽  
Emerson Carlos Soares ◽  
Elsa Oliveira ◽  
Sónia Rocha ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Density ◽  
Intercellular Space ◽  
Experimental Studies ◽  
Parasite Development ◽  
Parasitic Infections ◽  
Physicochemical Processes ◽  
Transmission Electron ◽  
Close Proximity

Abstract During a survey Myxozoa, four specimens of the sheepshead (18 ± 1.5 cm and 59 ± 2.5 g) (Archosargus probatocephalus) were collected in the Ipioquinha river (Maceió/AL). Transmission electron microscopy observations revealed erythrocyte agglutinations in gill capillaries located near spherical cysts containing myxospores of the genus Henneguya. This hemagglutination partially or totally obstructed the gill capillaries. Erythrocytes occurred in close adherence to each other, with a closed intercellular space. A few lysed erythrocytes were observed among agglutinated cells. The reduced lumen of the capillaries was partially filled with amorphous dense homogenous material adhering to the erythrocytes. In addition, heterogeneous masses of irregular lower electron density were observed in the reduced channel of the capillary. The agglutinated erythrocytes appeared dense and homogenous, lacking cytoplasmic organelles. The nuclei had the appearance of normal condensed chromatin masses, generally without visible nucleoli. This occurrence of hemagglutination only in the capillaries located in close proximity to the developing myxozoan cysts suggests that parasite development may be a factor triggering erythrocyte agglutination. This is supported by previous experimental studies that showed a probable correlation between parasitic infections and hemagglutination. Nonetheless, further studies are necessary in order to better understand the physicochemical processes involved in this phenomenon.

scholarly journals EFFECT OF ANTIBACTERIAL PREPARATIONS ON VIBRIO CHOLERAE EL TOR BIOFILMS

2017 ◽  
pp. 8-15 ◽  
Author(s):  
N. A. Selyanskaya ◽  
S. V. Titova ◽  
S. N. Golovin ◽  
L. A. Egiazaryan ◽  
L. M. Verkina ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Microbial Communities ◽  
Vibrio Cholerae ◽  
Electron Density ◽  
Bacterial Cell ◽  
Transmission Electron ◽  
The Matrix ◽  
El Tor ◽  
Selection Of

Aim. Study the effect of antibacterial preparations on biofilms of Vibrio cholerae El Tor. Materials and methods. Sensitivity of V. cholerae El Tor (6 strains) to various concentrations of antibacterial preparations (doxycycline, tetracycline, levomycetin, rifampicin, gentamycin, ceftazidime) was determined (MD 4.2.2495-09). Transmission electron microscopy was used for visualization of the effect of preparations on biofilms. Results. The values of minimal inhibiting concentrations of antibacterial preparations against biofilms have increased by 5 - 100 times compared with plankton cultures. Certain smoothing of strands between the bacterial cell and substrate, alteration of vibrios’ form, reduction of electron density of the matrix with an increase of its transparency were observed during electron-microscopy of the effect of antibacterial preparations on the biofilm. Conclusion. Study of the effect of antibacterial preparations on biofilms could increase effectiveness of rational antibiotics therapy of infections by selection of preparations that disrupt functioning of microbial communities.

Techniques for Transmission Electron Microscopy of Fiber-Matrix Interfaces in Aluminum Alloy-Boron Composites by Ion Erosio

1971 ◽  
Vol 29 ◽  
pp. 204-205
Author(s):  
G. G. Shaw
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Aluminum Alloy ◽  
Electron Beam ◽  
Pure Aluminum ◽  
Ion Milling ◽  
Transmission Electron ◽  
Fiber Matrix ◽  
Ion Erosion ◽  
Row Of Fibers

The morphology and composition of the fiber-matrix interface can best be studied by transmission electron microscopy and electron diffraction. For some composites satisfactory samples can be prepared by electropolishing. For others such as aluminum alloy-boron composites ion erosion is necessary.When one wishes to examine a specimen with the electron beam perpendicular to the fiber, preparation is as follows: A 1/8 in. disk is cut from the sample with a cylindrical tool by spark machining. Thin slices, 5 mils thick, containing one row of fibers, are then, spark-machined from the disk. After spark machining, the slice is carefully polished with diamond paste until the row of fibers is exposed on each side, as shown in Figure 1.In the case where examination is desired with the electron beam parallel to the fiber, preparation is as follows: Experimental composites are usually 50 mils or less in thickness so an auxiliary holder is necessary during ion milling and for easy transfer to the electron microscope. This holder is pure aluminum sheet, 3 mils thick.

Direct Observation of Heat Exchanger Deposits by Cross Sectioning

1967 ◽  
Vol 25 ◽  
pp. 364-365
Author(s):  
R. W. Anderson ◽  
D. L. Senecal
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Heat Exchanger ◽  
Direct Observation ◽  
Cross Sections ◽  
Preparation Method ◽  
Specimen Preparation ◽  
Flowing Water ◽  
Transmission Electron ◽  
Deposit Layer

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

1974 ◽  
Vol 32 ◽  
pp. 514-515
Author(s):  
S. Fujishiro
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Tensile Strength ◽  
Mechanical Processing ◽  
Ray Method ◽  
X Ray ◽  
Transmission Electron ◽  
Water Quench ◽  
Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

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).

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