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Full-Text Articles in Life Sciences
Diapause In The Earthworm, Aporrectodea Longa: Morphological And Quantitative X-Ray Microanalysis Of Cryosectioned Chloragogenous Tissue, A. J. Morgan, C. Winters
Diapause In The Earthworm, Aporrectodea Longa: Morphological And Quantitative X-Ray Microanalysis Of Cryosectioned Chloragogenous Tissue, A. J. Morgan, C. Winters
Scanning Microscopy
The earthworm, Aporrectodea longa, which experiences an apparent obligatory physiological resting state (“diapause”) in the temperate Summer, was collected monthly from February through to October. Morphological examination of the chloragocytes, and quantitative electron probe X-ray microanalysis of their constituent chloragosome granules prepared by cryoultramicrotomy and air-dried/smearing, were undertaken over this period. Worms entered diapause in May, and emerged from it between August and September. The long-term energy stores in the form of lipid, in addition to the more usual polysaccharide (glycogen) reserves, were accumulated by early diapause; the lipid was gradually consumed during diapause. In addition, the structure and composition …
A Scanning Electron Microscopic Study Of The Morphology Of Scyphidia Physarum Lachmann, 1856 (Ciliophora: Peritrichida), A. Warren
Scanning Microscopy
The morphology of Scyphidia physarum was investigated by scanning electron microscopy (SEM). Both contracted and uncontracted zooids were examined. The pellicular striations encircled the body at mean intervals of 1.1 µm. Pores were randomly distributed over the body surface with a mean density of 21 pores per 100 µm 2. The telotroch band was represented by three closely spaced striations. The adoral ciliature consisted of a single row of cilia in the haplokinety and three rows in the polykinety. The two sets of cilia were separated by a pellicular ridge. At the end of each row of cilia was a …
Advanced Sem Techniques To Characterize Coal Minerals, Christopher J. Zygarlicke, Edward N. Steadman
Advanced Sem Techniques To Characterize Coal Minerals, Christopher J. Zygarlicke, Edward N. Steadman
Scanning Microscopy
Research at the University of North Dakota Energy and Environmental Research Center (EERC) has focused on methods to characterize the inorganic components in coals. Because the scanning electron microscope and electron probe microanalysis system (SEM/EPMA) provide both morphologic and chemical information, the SEM/EPMA system is well-suited to the characterization of discrete minerals in coal. Computer-controlled scanning electron microscopy (CCSEM), along with simultaneous automated digital image collection, is one means of gaining more detailed insight into coal mineralogy. Computer-stored images of coal surfaces already analyzed for minerals using CCSEM can be reanalyzed to discern mineral morphologies and coal-to-mineral associations. Limitations may …
Ultrastructural Investigations Of The Bone And Fibrous Connective Tissue Interface With Endosteal Dental Implants, David E. Steflik, Ralph V. Mckinney, Allen L. Sisk, David L. Koth, Baldev B. Singh, Gregory R. Parr
Ultrastructural Investigations Of The Bone And Fibrous Connective Tissue Interface With Endosteal Dental Implants, David E. Steflik, Ralph V. Mckinney, Allen L. Sisk, David L. Koth, Baldev B. Singh, Gregory R. Parr
Scanning Microscopy
The interface between the tissues of the oral cavity and ceramic and titanium cylindrical endosteal dental implants was investigated with correlated light microscopy, transmission electron microscopy and scanning electron microscopy. This study suggested that mandibular bone can directly interface and form an intimate association with one-stage endosteal dental implants. This potential attachment matrix is composed of a composite of calcified bone, and an osteoid unmineralized matrix in association with an apparent osteogenic connective tissue. Further, results from this study suggested that at a level inferior to the junctional epithelium, and superior to the level of crestal bone, fibrous connective tissue …
Crystal Morphology Of Shortenings And Margarines, P. Chawla, J. M. Deman, A. K. Smith
Crystal Morphology Of Shortenings And Margarines, P. Chawla, J. M. Deman, A. K. Smith
Food Structure
An improved method is proposed for isolation of fat crystals with isobutanol, followed by fixation using osmium tetroxide vapours or cryo-fixation and visualization in the Scanning Electron Microscope (SEM). The cryo-fixation method revealed the presence of well defined needle-shaped or rod-shaped fat crystals. The osmium fixed crystals did not appear as distinct. The crystals existed as single crystals, platelets and spherulites. Polarized light micrographs did not show the details of the crystal morphology that were observed in the SEM.
Morphological Changes Of Hair Cell Stereocilia And Tectorial Membrane In Guinea Pigs With Experimentally Induced Hydrops, Sven Rydmarker, K. C. Horner
Morphological Changes Of Hair Cell Stereocilia And Tectorial Membrane In Guinea Pigs With Experimentally Induced Hydrops, Sven Rydmarker, K. C. Horner
Scanning Microscopy
Endolymphatic hydrops was surgically induced in guinea pigs. Atrophy of middle and short stereocilia on the outer hair cells in the upper 13 mm of the cochlea was systematically observed by scanning electron microscopy in guinea pigs with hydrops between 5-22 months. Light microscope and scanning electron microscope observations indicated that the tectorial membrane in the apical three turns was often abnormally elevated, and could be vertically positioned in longstanding hydrops. The atrophy of outer hair cell middle and short stereocilia and the elevation of the tectorial membrane certainly contribute to the pathophysiology of experimental hydrops and might be implicated …
A Monograph Of Sabal (Arecaceae: Coryphoideae), Scott Zona
A Monograph Of Sabal (Arecaceae: Coryphoideae), Scott Zona
Aliso: A Journal of Systematic and Floristic Botany
This monographic study of the New World genus Sabal (Arecaceae: Coryphoideae) recognizes 15 species. In addition to defining species limits and distributions, the study addresses broader questions concerning likely modes of speciation in the group and biogeographic radiation. The systematic treatment incorporates results from extensive field work and studies of leaf anatomy and flavonoid phytochemistry, ecology and biogeography, and morphology. Distribution maps and a key to the taxa are provided. Solutions are offered for the many nomenclatural problems that existed in the genus. A phylogenetic hypothesis, the first for the genus, is proposed. Moreover, phytochemical and anatomical features are examined …