Infiltration Macroscopic

Taken together, these biochemical and cellular transformations within the degenerating IVD result in macroscopic changes manifest as a dehydrated and fibrous NP, disorganized AF lamellae, and an inconspicuous boundary between the NP and AF. Concentric and/or radial annular tears, and NP fissure formations are also observed within the severely degenerated IVD, and an overall reduction in the central disc height may occur [11, 31]. Additionally, blood vessels and nerve endings have been found to infiltrate into the center of the disc, which may harbor inflammatory cells and their mediators. 

For applications where only mechanical properties are relevant, it is often sufficient to use resins for the filling and we end up with carbon-reinforced polymer structures. Such materials [23] can be soft, like the family of poly-butadiene materials leading to rubber or tires. The transport properties of the carbon fibers lead to some limited improvement of the transport properties of the polymer. If carbon nanotubes with their extensive propensity of percolation are used [24], then a compromise between mechanical reinforcement and improvement of electrical and thermal stability is possible provided one solves the severe challenge of homogeneous mixing of binder and filler phases. For the macroscopic carbon fibers this is less of a problem, in particular when advanced techniques of vacuum infiltration of the fluid resin precursor and suitable chemical functionalization of the carbon fiber are applied. 

Wood is built up of parallel columns of cells. Around these cells, cellulose embedded in lignin is wrapped. If wood is heated to temperatures above 600 °C (the exact temperature depends on the type of wood) in an inert atmosphere, then the polyaromatic biopolymers are broken down and what remains is a carbon skeleton with the anatomy of wood, both at a microscopic and macroscopic level. This skeleton facilitates the infiltration of, for instance, silicon and the reaction to silicon carbide. 

The application of ceramics has infiltrated almost all fields in the last 20 years, because of their advantages over metals due to their strong ionic or covalent bonding. But it is just this bonding nature of ceramics that directly results in their inherent brittleness and difficulty in machining. In other words, ceramics show hardly any macroscopic plasticity at room temperature or at low temperatures like metals. Hence, superplasticity at room temperature is a research objective for structural ceramics. In recent years, many researches have been carried out to investigate nanophase ceramic composites. 

This condition presents with diarrhoea the colonic mucosa is macroscopically normal but histologically shows either lymphocytic infiltration of the mucosa (lymphocytic colitis) or subendothelial fibrosis (collagenous colitis). Treatment with aminosalicylate induces remission in about 50% and corticosteroid may also be needed. 

Primary liver tumours can be categorized according to macroscopic criteria. The solitary coarse-granulomatous type is predominantly found in the right lobe, while the nodular multi-granulomatous type is most common in cirrhosis. The diffuse infiltrative type is relatively rare... 

Open-pore microcellular aluminium foams can be produced by a process known as replication . This consists in infiltration of NaCl powder preforms by a melt, which is then solidified to form a composite. The NaCl is subsequently leached out with water, to leave a network of open pores, of volume fraction roughly varying between 65 and 90% [15], The foams can be produced to feature good microstructural homogeneity over a comparatively wide range of metal alloy compositions, pore size and component shape. They furthermore serve as attractive model materials for the investigation of microstructure/property relations in metal foams because of their macroscopically uniform and fine-scale microstructure, and because the metal making the foam can be varied with relatively wide latitude and produced free of internal defects. 

White, I., and M.J. Sully. 1987. Macroscopic and microscopic capillary length and time scales from field infiltration. Water Resour. Res. 23 1514-1522. 

It has been shown that the ILG model can adequately simulate well-established macroscopic flow regimes, like Poiseuille s law (Di Pietro et al., 1994). The ILG model was also applied to study evaporation in porous media (Pot, 1994), infiltration in two-dimensional saturated and non-saturated porous media with macropores (Di Pietro, 1996) and water storage in roughed infiltrating and non-infiltrating surfaces (Garcia Sanchez et al., 1996). 

Macroscopic Appearance and Strength Characteristics. No difference in structural appearance can be seen in wood where only the pit membranes have been destroyed. Prolonged storage may, however, result in discoloration because of infiltration of substances from the water or chemical reactions. Strength losses, if any, are small. 

After 24 hours, the epidermal lesions are less intense, even if the macroscopic reaction is still very pronounced. There is an acanthosis. The infiltrate is still very extensive and the extravasations still very marked. 

In conclusion, although it is often difficult to distinguish macroscopically between the reactions due to the different eczematogens, this distinction becomes easier under microscopic examination when one considers the differences in the epidermal lesions (spongiosis, acanthosis, necrosis), the quality of the infiltrate, and the magnitude of this infiltration. 

In the first group, there are practically no epidermal lesions and there is a diffuse infiltrate (Fig. 36) whereas in the other 2 groups, the epidermal and dermal lesions are similar to those usually seen in eczema due to DNCB (Fig. 37). Hence, the macroscopic and microscopic tests do not correspond. 

Thus the results of the histological examination do not coincide with the aspect of the macroscopic lesions. However, we should keep in mind that, when we judge a macroscopic reaction, we appreciate only the dermal reactions while with a histological examination, the degree of the epidermal lesions and the nature of the infiltrate are also realized. 

Gastrointestinal In the acetic acid-induced colitis rat model for inflammatory bowel disease, lithium 20 mg/kg given 1 hour before the acetic acid ameliorated the macroscopic and microscopic gut abnormalities, including reduced neutrophil infiltration, reduced myeloperoxidase activity, and reduced lipid peroxidation [73 ]. 

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