Portulaca cypria Danin, P. granulatostellulata (Poelln.) Ricceri & Arrigoni, P. papillatostellulata (Danin & H. G. Baker) Danin (Portulacaceae Juss.) – new for the Ukrainian flora taxa from the territory of Transcarpathia

2019 ◽  
Vol 11 (1) ◽  
pp. 87-92
Author(s):  
O Bulakh ◽  
V Protopopova ◽  
M Shevera
Keyword(s):  
Smooth Surface ◽  
Portulaca Oleracea ◽  
Scanning Microscope ◽  
Surface Ultrastructure ◽  
Seed Surface ◽  
Degree Of Naturalization

The results of studying of seeds of the Portulaca oleracea L. (Portulacaceae Juss.) from Transcarpathia (Ukraine) are presented in the publication. The seed surface ultrastructure of taxa of the P. oleracea-aggr. based on the results of micromorphological studies with using electronic scanning microscope was described. The general for the representative of the genus (e.g. globous, ovate or almost reniform shaped of seeds; dark) and specify for the morphological types (star-shaped, isodiametric or elongate cells of seed surface with central part and long or short rays; smooth surface of seed or with knobs (from 0,03 mm in diameter) or papillae (0,01–0,02 mm in diameter), etc.) peculiarity are determined. The original figures of seed surface ultrastructure of the studied morphological types and key for its determination are prepared. As a results of investigation the new for the Ukrainian flora taxa, P. cypria Danin, P. granulatostellulata (Poelln.) Ricceri & Arrigoni and P. papillatostellulata (Danin & H.G. Baker) Danin, from Transcarpathia are presented. All studied species are: kenophytes according time of immigration; xenophytes, according way of distribution; and ephemerophytes, according degree of naturalization. The map of distribution of the taxa in the region is presented.

Portulaca oleracea aggregate (Portulacaceae) from the Chernivtsi Region (Ukraine)

2020 ◽  
Vol 12 (2) ◽  
pp. 251-262
Author(s):  
Olena Bulakh ◽  
Olena Volutsa ◽  
Alla Tokaryuk ◽  
Vasyl Budzhak ◽  
Ksenia Korzhan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Smooth Surface ◽  
Seed Morphology ◽  
Portulaca Oleracea ◽  
Scanning Microscope ◽  
Surface Ultrastructure ◽  
Seed Surface ◽  
Scanning Electron ◽  
Brown Color

At the results of investigation of micromorphology features of seed surface of the Portulaca oleracea aggr. (Portulacaceae Juss.) from Chernivtsi Region (Ukraine) six morphotypes of this taxa were recorded. Some peculiarities of the seed morphology of Portulaca L., and features of the ultrastructure of seed surface of the P. oleracea aggr. morphotypes, based on the results of micromorphological studies with using electronic scanning microscope was described. The general for the representative of the genus (e.g. globous, ovate or almost reniform shaped of seeds; black or dark brown color) and specify for the morphological types (star-shaped, isodiametric or elongate cells of seed surface with central part and long or short rays; smooth surface of seed or with knobs (from 0,03 mm in diameter) or papillae (0,01–0,02 mm), etc.) peculiarities are determined. The original scanning electron microscopy (SEM) photographs of seed surface ultrastructure of the studied morphological types and key fragment for its determination are suggested. According to our investigation six morphotypes of Portulaca oleracea aggr. are presented in Chernivtsi Region. Some of them are new for studied territory (P. granulatostellulata (Poelln.) Ricceri & Arrigoni, P. papillatostellulata (Danin & H.G. Baker) Danin), and other (Portulaca nitida (Danin & H.G. Baker) Ricceri & Arrigoni, P. trituberculata Danin, Domina & Raimondo, P. tuberculata (Danin & H.G. Baker) Danin) – new floristic records for Ukraine, and one of them (P. oleracea) – was known before also. The maps of distribution of this morphotypes in the region are presented. At the results of morphotypes distribution the most common is P. granulatostellulata and P. oleracea – rare in studied region like as in Europe also.

Surface Ultrastructure of Gram (−) Bacteria: I. Discrimination Between Gram (+) and Gram (−) Cells by Electron Microscopy

1974 ◽  
Vol 32 ◽  
pp. 176-177
Author(s):  
I. L. Uydess
Keyword(s):  
Electron Microscopy ◽  
Surface Topography ◽  
Smooth Surface ◽  
Osmium Tetroxide ◽  
Staining Technique ◽  
Negative Staining ◽  
Surface Ultrastructure

A modified negative staining technique (Osmium Tetroxide-Phosphotungstate procedure; OTPT) allows a detailed visualization and differentiation of the surface topography of Gram (+) and Gram (−) bacteria. All of the Gram (−) organisms studied exhibited a highly convoluted surface distinct from the apparently smooth surface of Gram (+) cells.

A contribution to taxonomy of Turkish Linum based on seed surface patterns

Biologia ◽  
2009 ◽  
Vol 64 (4) ◽  
Author(s):  
Tamer Özcan ◽  
Elçin Zorlu
Keyword(s):  
Seed Coat ◽  
Smooth Surface ◽  
Surface Textures ◽  
Surface Features ◽  
Seed Surface ◽  
Surface Patterns ◽  
Surface Microstructures

AbstractSeed samples of eighteen taxa from four sections in Linum were examined for diagnostic and taxonomic utility of the surface microstructures. Considerably different patterns were distinguished at specific and infraspecific levels. Similar sculpturings in closely related taxa and some common surface features for sectional groupings were observed. Smooth surface textures in sect. Linastrum, granulate-ruminate in sect. Dasylinum and rugulose structure in sect. Linum were typical characteristics. Sect. Syllinum exhibited miscellaneous patterns. Seed coat sculptures may be utilized as additional consistent parameters in the infrageneric delimitations and taxonomical association of Linum.

Atomic Force Microscopy and Scanning Electron Microscopy Reveal Genome–dependent Ultrastructure of Seed Surface

2001 ◽  
Vol 7 (6) ◽  
pp. 526-529
Author(s):  
T. Guha ◽  
R. Bhar ◽  
V. Ganesan ◽  
A. Sen ◽  
R.L. Brahmachary
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Contact Mode ◽  
Surface Ultrastructure ◽  
Force Microscopy ◽  
Seed Surface ◽  
Atomic Force ◽  
Different Strains ◽  
Scanning Electron

AbstractBoth scanning electron microscopy (SEM) and contact mode imaging via atomic force microscopy (AFM) have been utilized to elucidate the ultrastructure of mung bean seed surfaces. The results indicate: 1) that AFM is useful in the examination of seed surface ultrastructure ex-vaccuo without the need for additional complex preparative procedures; and 2) that both the cotyledon and seed coat of different strains of mung beans bear specific ultrastructural details unique to each strain. To our knowledge, these are the first AFM images of seed surfaces.

Effect of Contraceptive Steroids on the Endometrium of Guinea Pig: SEM study

1977 ◽  
Vol 35 ◽  
pp. 668-669
Author(s):  
Mai M. Said ◽  
Ramesh K. Nayak ◽  
Randall E. McCoy
Keyword(s):  
Guinea Pig ◽  
Reproductive Tract ◽  
Three Dimensional ◽  
Female Reproductive Tract ◽  
Human Female ◽  
Surface Ultrastructure ◽  
Transmission Electron ◽  
Sem Study ◽  
Uterine Mucosa ◽  
Group 1

Burgos and Wislocki described changes in the mucosa of the guinea pig uterus, cervix and vagina during the estrous cycle investigated by transmission electron microscopy. More recently, Moghissi and Reame reported the effects of progestational agents on the human female reproductive tract. They found drooping and shortening of cilia in norgestrel and norethindrone- treated endometria. To the best of our knowledge, no studies concerning the effects of mestranol and norethindrone given concurrently on the three-dimensional surface features on the uterine mucosa of the guinea pig have been reported. The purpose of this study was to determine the effect of mestranol and norethindrone on surface ultrastructure of guinea pig uterus by SEM.Seventy eight animals were used in this study. They were allocated into two groups. Group 1 (20 animals) was injected intramuscularly 0.1 ml vegetable oil and served as controls.

Closing the GAP—A 5Å Scanning Microscope

1969 ◽  
Vol 27 ◽  
pp. 6-7
Author(s):  
A. V. Crewe
Keyword(s):  
Normal Form ◽  
The Other ◽  
Resolving Power ◽  
Scanning Microscope ◽  
Conventional Microscope ◽  
Other Hand ◽  
Closing The Gap ◽  
Thermal Sources ◽  
Better Than ◽  
Transmission Microscope

We have become accustomed to differentiating between the scanning microscope and the conventional transmission microscope according to the resolving power which the two instruments offer. The conventional microscope is capable of a point resolution of a few angstroms and line resolutions of periodic objects of about 1Å. On the other hand, the scanning microscope, in its normal form, is not ordinarily capable of a point resolution better than 100Å. Upon examining reasons for the 100Å limitation, it becomes clear that this is based more on tradition than reason, and in particular, it is a condition imposed upon the microscope by adherence to thermal sources of electrons.

A New Image Processing Technique for STEM

1974 ◽  
Vol 32 ◽  
pp. 432-433
Author(s):  
Yasushi Kokubo ◽  
Hirotami Koike ◽  
Teruo Someya
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Scanning Electron Microscopy ◽  
Elastic Scattering ◽  
Field Emission ◽  
Processing Technique ◽  
Image Processing Technique ◽  
Energy Analyzer ◽  
Scanning Microscope ◽  
Scanning Electron

One of the advantages of scanning electron microscopy is the capability for processing the image contrast, i.e., the image processing technique. Crewe et al were the first to apply this technique to a field emission scanning microscope and show images of individual atoms. They obtained a contrast which depended exclusively on the atomic numbers of specimen elements (Zcontrast), by displaying the images treated with the intensity ratio of elastically scattered to inelastically scattered electrons. The elastic scattering electrons were extracted by a solid detector and inelastic scattering electrons by an energy analyzer. We noted, however, that there is a possibility of the same contrast being obtained only by using an annular-type solid detector consisting of multiple concentric detector elements.

A High Resolution Scanning Microscope

1968 ◽  
Vol 26 ◽  
pp. 356-357
Author(s):  
A. V. Crewe ◽  
J. Wall ◽  
L. M. Welter
Keyword(s):  
High Resolution ◽  
Field Emission ◽  
Spherical Aberration ◽  
Focal Length ◽  
Spot Size ◽  
Emission Source ◽  
Field Of View ◽  
Scanning Microscope ◽  
Magnetic Lens ◽  
High Quality

A scanning microscope using a field emission source has been described elsewhere. This microscope has now been improved by replacing the single magnetic lens with a high quality lens of the type described by Ruska. This lens has a focal length of 1 mm and a spherical aberration coefficient of 0.5 mm. The final spot size, and therefore the microscope resolution, is limited by the aberration of this lens to about 6 Å.The lens has been constructed very carefully, maintaining a tolerance of + 1 μ on all critical surfaces. The gun is prealigned on the lens to form a compact unit. The only mechanical adjustments are those which control the specimen and the tip positions. The microscope can be used in two modes. With the lens off and the gun focused on the specimen, the resolution is 250 Å over an undistorted field of view of 2 mm. With the lens on,the resolution is 20 Å or better over a field of view of 40 microns. The magnification can be accurately varied by attenuating the raster current.

The Potentials of Scanning Microscopy

1968 ◽  
Vol 26 ◽  
pp. 352-353
Author(s):  
A. V. Crewe
Keyword(s):  
Salient Feature ◽  
Secondary Emission ◽  
Resolving Power ◽  
X Rays ◽  
Scanning Microscope ◽  
Forming Process ◽  
Additional Tool ◽  
Detection Systems ◽  
Conventional Microscope ◽  
Present Information

If the resolving power of a scanning electron microscope can be improved until it is comparable to that of a conventional microscope, it would serve as a valuable additional tool in many investigations.The salient feature of scanning microscopes is that the image-forming process takes place before the electrons strike the specimen. This means that several different detection systems can be employed in order to present information about the specimen. In our own particular work we have concentrated on the use of energy loss information in the beam which is transmitted through the specimen, but there are also numerous other possibilities (such as secondary emission, generation of X-rays, and cathode luminescence).Another difference between the pictures one would obtain from the scanning microscope and those obtained from a conventional microscope is that the diffraction phenomena are totally different. The only diffraction phenomena which would be seen in the scanning microscope are those which exist in the beam itself, and not those produced by the specimen.

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