Video microscopy

Particles can be manipulated in suspension using strongly focused laser beams ( optical tweezers ) [25] or magnetic fields [26] and by collecting statistics on tire particle movements using video microscopy, infonnation on the particle interactions can be obtained. 

S. InouH, Video Microscopy, Plenum Publishing Corp., New York, 1986. 

The classical polarizing light microscope as developed 150 years ago is still the most versatile, least expensive analytical instrument in the hands of an experienced microscopist. Its limitations in terms of resolving power, depth of field, and contrast have been reduced in the last decade, in which we have witnessed a revolution in its evolution. Video microscopy has increased contrast electronically, and thereby revealed structures never before seen. With computer enhancement, unheard of resolutions are possible. There are daily developments in the X-ray, holographic, acoustic, confocal laser scanning, and scanning tunneling micro-... 

Unlike solid electrodes, the shape of the ITIES can be varied by application of an external pressure to the pipette. The shape of the meniscus formed at the pipette tip was studied in situ by video microscopy under controlled pressure [19]. When a negative pressure was applied, the ITIES shape was concave. As expected from the theory [25a], the diffusion current to a recessed ITIES was lower than in absence of negative external pressure. When a positive pressure was applied to the pipette, the solution meniscus became convex, and the diffusion current increased. The diffusion-limiting current increased with increasing height of the spherical segment (up to the complete sphere), as the theory predicts [25b]. Importantly, with no external pressure applied to the pipette, the micro-ITIES was found to be essentially flat. This observation was corroborated by numerous experiments performed with different concentrations of dissolved species and different pipette radii [19]. The measured diffusion current to such an interface agrees quantitatively with Eq. (6) if the outer pipette wall is silanized (see next section). The effective radius of a pipette can be calculated from Eq. (6) and compared to the value found microscopically [19]. 

In video microscopy, for instance, background is normally subtracted using differential interference contrast (DIC) [18]. This technique, which requires a number of manipulations from the user, may now be automated using a new method called polarization-modulated (PMDIC) [19,20], It requires the introduction of a liquid crystal electro-optic modulator and of a software module to handle difference images. PMDIC has been shown to bring improvements in imaging moving cells, which show a low contrast, as well as thick tissue samples. 

ED Salmon, P Tran. In G Sluder and DE Wolf, eds. Video Microscopy. New York Academic Press, 1998, Chapter 9. 

Mechanical functions of cells require interactions between integral membrane proteins and the cytoskeleton 29 The spectrin-ankyrin network comprises a general form of membrane-organizing cytoskeleton within which a variety of membrane-cytoskeletal specializations are interspersed 29 Interaction of rafts with cytoskeleton is suggested by the results of video microscopy 29... 

Video microscopy allows study of molecular mechanisms through direct observation of organelle movements while precise control of experimental conditions is maintained. Fast axonal transport continues unabated in isolated axoplasm from giant axons of the squid Loligo pealeii for hours [14]. Video microscopy applied to isolated axoplasm permits a more rigorous dissection of the molecular mechanisms for fast axonal transport... 

Brady, S. T., Lasek, R. J. and Allen, R. D. Video microscopy of fast axonal transport in isolated axoplasm A new model for study of molecular mechanisms. Cell Motil. 5 81-101, 1985. 

Weiss DG, Marie W, Wick RA. Video microscopy, in Light Microscopy in Biology A Practical Approach (Lacey AJ, ed.), IRL Press, Oxford, UK, 1989, pp. 221-278. 

Callow ME, Callow JA, Pickett-Heaps JD, Wetherbee R (1997) Primary adhesion ofEnteromorpha (Chlorophyta, Ulvales) propagules Quantitative settlement studies and video microscopy. J Phycol 33 938-947... 

Gastrointestinal Peristalsis (number and amplitude of the contractions) Video microscopy of fluorescent diets Farber et al. 211 Wallace and Pack212... 

Video microscopy has permitted direct observation of microtubule assembly/disassembly dynamics in vitro. Horio and HotanP first used dark-field optics to observe the growth and shrinkage phases, but so-called Allen video-enhanced contrast microscopy has become most convenient. 

Video microscopy with crossed polarizers permits the direct and non-invasive observahon of the nucleahon and growth process for many substances, and thus the study of the hme evoluhon of the spherulite radius R t). When the growth is controlled by diffusion the radius of the spherulites increases as R t) a while when the growth is determined by a nucleation-controlled process (incorporahon of atoms or molecules to the surface of the crystalline part) the radius increases linearly with hme, R t) a t. 

Figure 10.9 Video-microscopy images of positively charged CL/DNA complexes in the (A) iiand(B) phases, and interacting with negatively charged giant (G) vesicles (C and D). In all cases, complexes were viewed in (DIC) (left), lipid fluorescence (middle), and DNA fluorescence (right). The scale bar for DIC is 3 gpm for (A) (B), and 20 ppm...

Video-microscopy images of positively charged CL/DNA complexes in the (A) and (B) 184... 

Inoue, S. 1986. Video Microscopy . Plenum Press, New York. 

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