Dendritic patterns

Lamina IV is composed of heterogeneous sized cells and is less densely packed than lamina III due to the number of nerve axons passing in this layer. At least three types of neurons have been identified in lamina IV, based on different dendritic projection patterns and these include SCT and PSDC cells. Another cell type has been described which has a dendritic pattern similar to SCT and PSDC, but with local axon terminations. Somas of STT cells are also found in lamina IV. 

Figure 2.2. (a) Coiled whisker of rutile in cabochon-cut quartz (courtesy of E. A. Jobbins). (b) Crysotile crystals resembling stacked ice cream cones. (Transmission electron microphotograph taken by K. Yada.) (c) Pyrolusite polycrystalline dendritic pattern formed along a bedding plane of sedimentary rock. 

Connection between Transport Processes and Solid Microstructure. The formation of cellular and dendritic patterns in the microstructure of binary crystals grown by directional solidification results from interactions of the temperature and concentration fields with the shape of the melt-crystal interface. Tiller et al. (21) first described the mechanism for constitutional supercooling or the microscale instability of a planar melt-crystal interface toward the formation of cells and dendrites. They described a simple system with a constant-temperature gradient G (in Kelvins per centimeter) and a melt that moves only to account for the solidification rate Vg. If the bulk composition of solute is c0 and the solidification is at steady state, then the exponential diffusion layer forms in front of the interface. The elevated concentration (assuming k < 1) in this layer corresponds to the melt that solidifies at a lower temperature, which is given by the phase diagram (Figure 5) as... 

Fig. 1.10 S ubstance crystallising in dendritic patterns [25 b] (Fr chet dendron of the second generation)...

Akum BF, Chen M, Gunderson SI, Riefler GM, Scerri-Hansen MM, et al. 2004. Cypin regulates dendritic patterning in hippocampal neurons by promoting microtubule assembly. 

Chen M, Lucas KG, Akum BF, Balasingam G, Stawicki TM, et al. 2005. A novel role for snapin in dendritic patterning Interaction with cypin. Mol Bio Cell 16 5103-5114. 

Hydrothermal, low temperature precipitation, and vapor deposition produce different crystal habits and sizes due to differences in growth rates, diffusion rates, and surface energy. Most Fe-Mn oxide-hydroxide phases are formed at low temperatures (below 100° C), but several are known to form unde hydrothermal conditions (above 100° C and up to several kbars pressure). Larger crystals are produced from hydrothermal processes as transport is much more rapid, and solubility of the growing phase in the growth medium (solution) is high. The latter growth process can produce crystals up to 10 cm in size. Ice crystals (snowflakes) are the most commonly observed vapor deposition-produced natural phases. These usually show complex dendritic patterns caused by rapid... 

Rakic P. 1972. Extrinsic cytological determinants of basket and stellate cell dendritic pattern in the cerebellar molecular layer. J Comp Neurol 146 335-354. 

As already noted, when the LE phase is expanded, bubbles of gas grow and thin lamellae of fluid are left between them, forming a two-dimensional foam structure (Fig. 10a) in which the size of the cells and the distribution of the number of sides changes with time. Dendritic structures (Fig. 21) are observed in the LE-LC transition region when the monolayer is compressed, or in temperature quenches from the LE one-phase region into the two-phase region. In the case of fatty acids,only circular islands are observed at low temperature, even with rapid compression. The temperature threshold for the appearance of dendritic patterns is quite sharp. Such structures are also found in phospholipid monolayers. ... 

Scheibel M, Scheibel A, Walberg F, Brodal A (1956) Areal distribution of axonal and dendritic patterns in inferior olive. J. Comp. Neurol, 106, 21-50. 

A number of experimental and simulation work has been carried out in recent decades which obviously improved the elementary knowledge about the growth of dendritic crystal patterns. Some modem technique has also been has investigated which can replicate the true geometry of dendrites and validated experimentally both in space and time scales. This has led to elucidate new pattern formation mechanisms which broaden the scope of our understanding in dendritic pattern formation in diverse held of material science. 

Dendritic patterns are one of the most frequently observed forms in both abiotic systems and biological systems. Examples include the roots and branches of trees, snow crystals, neurons, and capillary vessels. Dendrimers are macromolecules, which are based on repeatedly branched building blocks from a core molecule. The name dendrimer, comes from the Greek dendron, meaning... 

Stainless steels Kalling s reagent Develops dendritic pattern. Darkens ferrite and martensite, austenite light, does not attack carbides. 

Ramos, B., Gaudilliere, B., Bonni, A., et al., 2007. Transcription factor Sp4 regulates dendritic patterning during cerebellar maturation. Proc. Natl. Acad. Sci. USA 104, 9882-9887. 

The model was tested for many cases of electrically enhanced and non-enhanced filtration. The location of each particle in each dendrite was recorded. The resulting data can only be usefully discussed if presented in graphical form. Plots of two views of each simulation were generated. Because each simulation must be considered as a single event of a random process, it was necessary to generate many plots for the same simulation conditions. The dendrite patterns included in this report were chosen as typical examples of various sets of simulation conditions. 

Deposition in Fibrous Media With Dendrite Pattern, AIChE J., vol. 23, pp. 192, 1977. 

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