Laminar structures

Reelin is an extracellular matrix protein, which is secreted by neuronal cells and binds to two lipoprotein receptors (VLDLR and ApoER2) that relay the Reelin signal inside target neurons by docking the tyrosine kinase adapter disabled-1 (Dabl). This allows neurons to complete migration and adopt their ultimate positions in laminar structures in the central nervous system. In... 

Both columnar and laminar structures are optically active to polarized light and usually have similar physical properties. 

What molecular machinery controls these forms of synaptic plasticity One of the most studied brain regions is the CA1 region of the hippocampus the CA1 region is not only crucial for memory formation (profound amnesia in patient R. B with selective CA1 lesion), but also exhibits a well-organized laminar structure ideal for electrophysio-logical recording. 

Observation of the nature of the corrosion products on buried glass goes back at least as far as Brewster (1863), who reported the characteristic flakiness and surface iridescence. Under the microscope he observed a fine laminar structure with a range of thicknesses between 0.3 and 15 pm, which he deduced... 

Diy EVOH/PP-g-maleic mldehyde (MAH) blend, obtained by moulded injection also evidenced good barrier properties for toluene. This property is improved by increasing EVOH concentration which determines both size and deformation of the minor phase increase, indicating that the laminar structure becomes more pronounced [296], But even the laminar structure is maximized a moulded injection sample is not likely to reach a permeability as low as expected for a multilayered system [296],... 

Good methanol/gasoline fuel permeation resistance together with clearly defined MPAPVA and MPA laminar structures were found in containers blow-molded from PE/PMPAPVA and PE/MPA blends, respectively, with an optimum CP of about 20 wt% [302],... 

Black phosphorus is the third major adotropic form of phosphorus. It occurs in two forms, one is an amorphous modification having a laminar structure similar to graphite and the other is an orthorhombic crystalline form. The density of black phosphorus may vary between 2.20 to 2.69 g/cm. Black phosphorus is obtained from white phosphorus by heating the latter at 220°C under an extremely high pressure of about 10,000 atm. 

In laminar structures such as the cerebral and cerebellar cortices, glial cells of a specialized nature, which are... 

Figure 10. Electron micrograph of brain lipid surface film formed in presence of Ca2+ and ATP. Presence of myelin-like laminar structure indicated by arrow, X 22,500...

The vitrinite without any sheets appears to correspond to what Brown, Cook, and Taylor (2) have called vitrinite A that with sheets appears to correspond to vitrinite B. The existence of this kind of laminar structure helps to explain the observation that vitrinite B has a higher volatile matter yield than vitrinite A although some of the coking properties of the two vitrinite types seem fairly similar. Many of the coking properties in fact appear to be primarily related to the matrix vitrinite. 

In hardness anisotropy determination, maximum differences are observed in minerals of lower symmetry or fibrous and laminar structure. The degree of anisotropy is estimated through the coefficient of anisotropy... 

Design of asymmetric laminar structures tailored for specific use. 

The super-fine dispersoids with laminar structure and a low modulus could be expected to play a crucial role in improving the machinability of ceramics and their mechanical properties. Among the various nanocomposites, h-BN reinforced composites showed excellent corrosion resistance to molten metal... 

In summary, the arthropod cuticle is not chitinous and can probably best be described as a plasticized, protein sheet, variously subdivided to give a laminar structure by (a) the addition of waxes at the outer surfaces and chitin in the inner parts, and (b) hardening due to impregnation with calcium salts or further polymerization with polyphenols, or both. 

The hippocampus is a symmetrical structure located inside the medial temporal lobe on both sides of the human brain. In cross-sections, the hippocampus consists of two interlocking sheets of cortex with three distinct sub-regions the dentate gyrus, the hippocampus proper (CAl—CA3) and the subic-ulum. The hippocampus has a highly defined laminar structure with visible layers of pyramidal cells arranged in rows. A striking feature of hippocampus is its connection circuitry. 

The retina has a highly organized laminar structure that is similar in all vertebrate species (Figure 11.IB Dowling, 1987 RocUeck, 1998). It is oriented so that photoreceptors lie at the back, adjacent to the RPE. Thus, to reach the... 

The same laminate system was used by all laboratories, namely a laminar structure with five layers based on polypropylene (PP), an adhesive, an ethylene vinyl alcohol (EVOH) layer another adhesive and another polypropylene layer. This is designated PP/adh/EVOH/adh/PP and was used in both fixed arm peel tests and T-peel tests. Peel specimen were 15 mm in width and a notional 100 mm in length. The peel arms were PP/adh (with a thickness of 51pm) and EVOH/adh/PP (with a thickness of 75pm). Although there is no rigorous value for modulus for such multi-layered arms, we have obtained a tensile modulus value for each arm and assumed the materials of the arms to be uniform for the purposes of our calculations. 

The pyrolysis reactions take place at temperatures between 800 and 3000°C, both in the gas phase and on the substrate surface. Their property mix can be varied within wide limits by appropriate choice of process parameters. The production of an isotropic structure is just as possible as the obtaining of spiral, columnar or extremely anisotropic laminar structures. Graphite whiskers can also be produced. 

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