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Full-Text Articles in Life Sciences
Optimization And Application Of Jet-Freezing, T. Müller, S. Moser, M. Vogt, C. Daugherty, M. V. Parthasarathy
Optimization And Application Of Jet-Freezing, T. Müller, S. Moser, M. Vogt, C. Daugherty, M. V. Parthasarathy
Scanning Microscopy
Cryofixation is considered to be the best method for immobilizing biological material in its natural state. In jet-freezing, the specimen typically is sandwiched between two carriers and kept in place while a coolant is moved very rapidly against the opposite surfaces. The JFD 030 jet-freezing device has been used to optimize the operating parameters. The course of the temperature in place of a specimen was measured with thermocouples and recorded by an IBM-compatible personal computer using a specifically developed software program. Mean cooling rates, over the temperature range of 273K to 173K, achievable with different cryogens, including the non-flammable HCFC …
Contributions Of Electron Microscopy To The Study Of The Hypertrophic Scar And Related Lesions, C. Ward Kischer
Contributions Of Electron Microscopy To The Study Of The Hypertrophic Scar And Related Lesions, C. Ward Kischer
Scanning Microscopy
Prior to 1969, only one study of the hypertrophic scar had been done using electron microscopy, and that one used electron diffraction. Since that time, studies using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been integral in establishing not only the characteristics of this lesion but in formulating the reasons why the scar develops and how it resolves. The first SEM studies demonstrated a homogeneous, dense dermal matrix which supported the conclusion that the hypertrophic scar and keloid reflected excess collagen. These same studies were integral in identifying the collagen nodule as the basic anatomical unit of …
Observations On The Enamel Of Odontomas, Carla Marchetti, Cesare Piacentini, Paolo Menghini, Marcella Reguzzoni
Observations On The Enamel Of Odontomas, Carla Marchetti, Cesare Piacentini, Paolo Menghini, Marcella Reguzzoni
Scanning Microscopy
The morphological study of odontomas provides an alternative model for observing the formation of dental tissues, since different maturing stages are present simultaneously. Investigations were performed on decalcified samples (using light microscopy and transmission electron microscopy) and on undecalcified samples of complex odontoma enamel (using transmission electron microscopy). Simultaneous presence of prismatic enamel at various maturing stages with different structural characteristics was observed. Such enamel was sometimes associated with layers of ameloblastic cells with characteristics of cells in functional activity. In other sites, the enamel did not present a prismatic structure but it appeared as unstructured material clusters with abundant …
Casting With Mercox-Methylmethacrylic Acid Mixtures Causes Plastic Sheets On Elastic Arteries. A Scanning And Transmission Electron Microscopic Study, Seyedhossein Aharinejad, Peter Böck
Casting With Mercox-Methylmethacrylic Acid Mixtures Causes Plastic Sheets On Elastic Arteries. A Scanning And Transmission Electron Microscopic Study, Seyedhossein Aharinejad, Peter Böck
Scanning Microscopy
Lungs and systemic vessels of rats were cast with Mercox, both undiluted and diluted with monomeric methylmethycrylate (MMA; v:v/4:1), and studied by scanning electron microscopy (SEM). A sheet, less than 5 μm thick, surrounded the surface of cast pulmonary arteries and the aorta, when using diluted Mercox. This envelope was absent when casts were prepared with undiluted Mercox. Transmission electron microscopy (TEM) of unmacerated cast arteries showed all constituents of the vascular wall. Sections of thoroughly macerated vascular casts, however, still showed elastic lamellae in the vascular wall region, whereas muscular components and endothelial lining were completely digested. It is …
Transmission Electron Microscopy And Nanoprobe Analysis Of Ferroelectric Thin Films, Maria Huffman, Mowafak M. Al-Jassim, Chuck Echer
Transmission Electron Microscopy And Nanoprobe Analysis Of Ferroelectric Thin Films, Maria Huffman, Mowafak M. Al-Jassim, Chuck Echer
Scanning Microscopy
Thin-film ceramic materials have a variety of electronic applications. Several deposition techniques are currently being used to produce such films with specific properties. For example, rf-sputtered ferroelectric perovskite films, with total thicknesses less than 0.5 μ.m, are being integrated with semiconductor devices as elements for non-volatile memories. Since there is a definite need to characterize these thin films after deposition, electron microscopy has been utilized as one of the most powerful techniques available for examining their morphology and microstructure. Transmission electron microscopy (TEM) examination of these oxides proved difficult. New TEM sample preparation techniques had to be developed in order …