Orientation map

Randle, V. and Engler, O. (2000) Macrotexture, Microtexture and Orientation Mapping (Gordon Breach, New York). 

Figure 18 Quantitative

The program CGF ([Har]) generates 3-valent orientable maps with specified genus and />vector. 

Rats who are learning maze navigation will often show correlated firing of neuron pairs in the area of the brain known as the hippocampus, and this firing increases as they learn, as if neurons were making a physical link to represent the animal s orientational maps. The cross-correlation re-emerges at sleep onset, as if the rat s brain, like the brain of the Tetris ox Alpine Rarer player, was repeating in sleep the cerebral code from its daytime experience. The cellular and molecular basis of this phenomenon can now be studied. 

Electron backscatter diffraction (EBSD) — The focused electron beam of Scanning Electron Microscopes (SEM) can be used to detect the crystallographic orientation of the top layers of a sample. The backscattered electrons (information depth 40-70 nm at 25 kV accelerating potential, lateral resolution around 200 nm) provide characteristic diffraction patterns (Kikuchi lines) on a phosphor screen. The patterns are recorded by a CCD-camera and interpreted by software. The position of the unit cell of the sample is determined by the corresponding Euler angles. In scanning mode, the software produces a surface orientation mapping that consists of... 

Other names instead of EBSD are Backscatter Kikuchi Diffraction (BKD), Electron Backscatter Pattern Technique (EBSP), Orientation Imaging Microscopy (OIM ), or Automated Crystal Orientation Mapping (ACOM). In combination with electrochemical studies only ex situ applications are possible. 

Figure 50.10. Diffusion tensor imaging results from a mouse brain imaging study at 7 T. (A) mean diffusisivity (D ) (B) Fractional Anisotropy (FA), (C) Color coded FA orientation map.

Fig. 8.11. (a) -(c) SEM images of three types of surface microstructure in range of 355-600 pm obtained by the drop tube method, (d)-(f) EBSP crystallographic orientation maps for cross-sections of typical samples, which corresponds with Fig. 8.3a—c, respectively... 

Obermayer K, Blasdel GG. 1997. Singularities in primate orientation maps. Neural Comput 9 555-575. 

Schummers J, Marino J, Sur M. 2002. Synaptic integration by VI neurons depends on location within the orientation map. Neuron 36(5) 969-978. 

Fiber orientation mapping provides information on white matter tract structure, integrity, and connectivity... 

Figure 18 Schematic rendering of the two surfaces of section IX nd Xq used to define the n-map for a double-weil system. We associate each map with a potential minimum, likely to be associated with an attractive PODS. As the trajectory winds through phase space, we record its iocation as it passes each plane with the proper orientation (mapped points are indicated by an asterisk ( )).

Hsu, E.W., Muzikant, A.L., Matulevicius, S.A. et al.. Magnetic resonance myocardial fiber-orientation mapping with direct histological correlation. Am. J. Physiol, 274, HI627 HI634, 1998. 

Fig. 4.1 The crystal structure of hematite as seen looking down the [001] direction (left) and the [8] direction (right). Oxygen anions are dark gray and iron cations are light gray. The unit cell is outlined, and the orientation map is shown for each view...

Examinations of the microstructure were carried out on an optical microscope Leica QWin and in the scanning electron microscope SEM XL30, Philips. In order to illustrate microstructures (the phase contrast and crystallographic orientation maps) backscattered electrons (BSE) and diffractions of them (EBSD) in SEM were used. For observations of surface morphology secondary electrons (SE) were used. 

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