Morphobiological aspects of Rhodnius brethesi Matta, 1919 (Hemiptera:Reduviidae) from the Upper and Middle Negro River, Amazon region of Brazil: I - scanning electron microscopy

The diamonds from the Painin garimpo, on the Tapajós River, in Itaituba, state of Pará, were mined in alluvial gravel in geological terrains dominated by the Barreirinha, Itaituba and Monte Alegre Paleozoic formations. 30 diamonds extracted from the concentrates of this garimpo were analyzed by stereomicroscopy, optical microscopy, x-ray diffraction, scanning electron microscopy with EDS and luminescence. The average weight of these specimens is 0.42 ct and the predominant forms are dodecahedral and octahedral, in addition to others such as ballas and bort. Surface figures, microstructures, luminescence, and various inclusions are recognized. The inclusions can be classified as syngenetic (periclase, diopside, among others) and epigenetic (eg minerals of crandallite group). Green covers were also observed. This study, however, was not able to solve the problem of the genesis of the diamond in the studied region, as happens to date with most secondary diamond deposits in the Amazon region (Tapajós, Tocantins and Tepequém-Maú), except for those related to kimberlite pipes of Mato Grosso Rondônia.

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Four new Pinnularia Ehrenberg (Bacillariophyta, Pinnulariaceae) species from Amazonian black water (Tupé Lake, Amazonas State, Brazil)

Phytotaxa ◽

10.11646/phytotaxa.158.2.3 ◽

2014 ◽

Vol 158 (2) ◽

pp. 154 ◽

Cited By ~ 5

Author(s):

Andreia Cavalcante Pereira ◽

Lezilda Carvalho Torgan ◽

Sergio Melo

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Sustainable Development ◽

Low Ph ◽

Taxonomic Study ◽

The Sustainable Development ◽

Black Water ◽

Negro River ◽

Amazonas State ◽

Scanning Electron

Tupé Lake belongs to one of the Sustainable Development Reserves in the Negro River Basin, Amazonas State, Brazil. It connects to the Negro river by a channel, so its level varies according to the floods of the river. The water has low pH (< 5), low conductivity (< 7.60 µS.cm-1) and high temperature (> 28.5ºC). During a taxonomic study of the genus Pinnularia, four new species are described: P. manausensis Pereira & Torgan, P. nelsonii Pereira & Torgan, P. tupensis Pereira, Melo & Torgan and P. walkerae Pereira & Torgan. The study was based on samples taken during October and December 2003 (low waters) and September 2008 (falling), including samples of plankton and sediment. The morphology of the species is compared to closely related (similar) taxa. Detailed valve structures of some species are documented with scanning electron microscopy.

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Pathogenesis of Human Hair Defects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005007x ◽

1974 ◽

Vol 32 ◽

pp. 12-13

Author(s):

P.S. Porter ◽

T. Aoyagi ◽

R. Matta

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Human Hair ◽

Standard Techniques ◽

Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

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Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080614 ◽

1977 ◽

Vol 35 ◽

pp. 638-639

Author(s):

P.J. Dailey

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Salivary Glands ◽

Secretory Vesicles ◽

The Past ◽

Transmission Electron ◽

Means Of Transmission ◽

Gromphadorhina Portentosa ◽

Scanning Electron ◽

Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

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Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081279 ◽

1978 ◽

Vol 36 (2) ◽

pp. 82-83 ◽

Cited By ~ 1

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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Spontaneous Cataract in Nude Athymic Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079991 ◽

1977 ◽

Vol 35 ◽

pp. 512-513

Author(s):

Ronald H. Bradley ◽

R. S. Berk ◽

L. D. Hazlett

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Nude Mouse ◽

Cellular Immunity ◽

Phosphate Buffer ◽

Osmium Tetroxide ◽

Athymic Mice ◽

Transmission Microscopy ◽

Mouse Lens ◽

Scanning Electron

The nude mouse is a hairless mutant (homozygous for the mutation nude, nu/nu), which is born lacking a thymus and possesses a severe defect in cellular immunity. Spontaneous unilateral cataractous lesions were noted (during ocular examination using a stereomicroscope at 40X) in 14 of a series of 60 animals (20%). This transmission and scanning microscopic study characterizes the morphology of this cataract and contrasts these data with normal nude mouse lens.All animals were sacrificed by an ether overdose. Eyes were enucleated and immersed in a mixed fixative (1% osmium tetroxide and 6% glutaraldehyde in Sorenson's phosphate buffer pH 7.4 at 0-4°C) for 3 hours, dehydrated in graded ethanols and embedded in Epon-Araldite for transmission microscopy. Specimens for scanning electron microscopy were fixed similarly, dehydrated in graded ethanols, then to graded changes of Freon 113 and ethanol to 100% Freon 113 and critically point dried in a Bomar critical point dryer using Freon 13 as the transition fluid.

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Scanning and Transmission Microscopy of Nematocyst Batteries in Epitheliomuscular Cells of Hydra

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066097 ◽

1971 ◽

Vol 29 ◽

pp. 410-411 ◽

Cited By ~ 1

Author(s):

Jane A. Westfall ◽

S. Yamataka ◽

Paul D. Enos

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Osmium Tetroxide ◽

External Surface ◽

Three Dimensional ◽

Surface Structures ◽

Transmission Microscopy ◽

Transmission Electron ◽

Freeze Dried ◽

Scanning Electron

Scanning electron microscopy (SEM) provides three dimensional details of external surface structures and supplements ultrastructural information provided by transmission electron microscopy (TEM). Animals composed of watery jellylike tissues such as hydras and other coelenterates have not been considered suitable for SEM studies because of the difficulty in preserving such organisms in a normal state. This study demonstrates 1) the successful use of SEM on such tissue, and 2) the unique arrangement of batteries of nematocysts within large epitheliomuscular cells on tentacles of Hydra littoralis.Whole specimens of Hydra were prepared for SEM (Figs. 1 and 2) by the fix, freeze-dry, coat technique of Small and Màrszalek. The specimens were fixed in osmium tetroxide and mercuric chloride, freeze-dried in vacuo on a prechilled 1 Kg brass block, and coated with gold-palladium. Tissues for TEM (Figs. 3 and 4) were fixed in glutaraldehyde followed by osmium tetroxide. Scanning micrographs were taken on a Cambridge Stereoscan Mark II A microscope at 10 KV and transmission micrographs were taken on an RCA EMU 3G microscope (Fig. 3) or on a Hitachi HU 11B microscope (Fig. 4).

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Microbulldozing and Microchiseling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062580 ◽

1969 ◽

Vol 27 ◽

pp. 134-135

Author(s):

J.N. Ramsey ◽

D.P. Cameron ◽

F.W. Schneider

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Material Handling ◽

Microprobe Analysis ◽

Foreign Matter ◽

Specific Location ◽

Potential Problems ◽

Knoop Indenter ◽

Scanning Electron ◽

Microhardness Tester

As computer components become smaller the analytical methods used to examine them and the material handling techniques must become more sensitive, and more sophisticated. We have used microbulldozing and microchiseling in conjunction with scanning electron microscopy, replica electron microscopy, and microprobe analysis for studying actual and potential problems with developmental and pilot line devices. Foreign matter, corrosion, etc, in specific locations are mechanically loosened from their substrates and removed by “extraction replication,” and examined in the appropriate instrument. The mechanical loosening is done in a controlled manner by using a microhardness tester—we use the attachment designed for our Reichert metallograph. The working tool is a pyramid shaped diamond (a Knoop indenter) which can be pushed into the specimen with a controlled pressure and in a specific location.

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A New Image Processing Technique for STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052171 ◽

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.

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Fibroblasts During Hypertrophic Scar Formation and Resolution

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072587 ◽

1973 ◽

Vol 31 ◽

pp. 428-429

Author(s):

C. W. Kischer

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Cell Proliferation ◽

Fine Structure ◽

Metabolic Activity ◽

Hypertrophic Scar ◽

Normal Skin ◽

Ground Substance ◽

Hypertrophic Scars ◽

Scanning Electron

The morphology of the fibroblasts changes markedly as the healing period from burn wounds progresses, through development of the hypertrophic scar, to resolution of the scar by a self-limiting process of maturation or therapeutic resolution. In addition, hypertrophic scars contain an increased cell proliferation largely made up of fibroblasts. This tremendous population of fibroblasts seems congruous with the abundance of collagen and ground substance. The fine structure of these cells should reflect some aspects of the metabolic activity necessary for production of the scar, and might presage the stage of maturation.A comparison of the fine structure of the fibroblasts from normal skin, different scar types, and granulation tissue has been made by transmission (TEM) and scanning electron microscopy (SEM).

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