Neurons are about as polarized as cells ever get. Their axonal process can extend a distance that is up to a million times the diameter of the nerve cell body. Axons have none of the ribosomal machinery responsible for protein synthesis, so all neuronal proteins and peptides must be manufactured near the nucleus and carried out to the periphery. This distribution involves at least two distinct mechanisms, fast axonal transport, moving at almost 500 mm per day, and slow axonal transport, moving only 0.1 to 3 mm per day. It turns out that proteins of the neuronal cytoskeleton, along with many soluble cytosolic proteins, are transported exclusively by the slower process.

The particle size of organic pigments used in modern coatings is extremely fine. Since these individual pigment crystals are typically less than 1 μm in size, they are difficult, if not impossible, to characterize and identify by microscopical means. The occurrence of occasional pigment aggregates may help identify a pigment to a microscopist who is familiar with a variety of known pigments under controlled conditions. More often, however, such observations provide a qualitative basis for comparison of questioned and known paints without leading to identification of the specific pigments involved. Microscopic observations of this type are assisted by the use of a high-magnification oil immersion objective and condenser with numerical apertures of 1.25 or greater.

Most of the applications in microscopic image analysis are still salved by a heuristic method that focuses on the specificity of each problem. This is particularly true for applications involving color images. Because of this, the design of robust algorithms has remained time consuming and is usually performed by an image analysis expert with many years of experience. How then can the knowledge of the expert be transferred to the less specialized microscopist? How can the specificity of a typical application be related to general color image analysis tools?

Only a general approach can work towards decreasing the heuristic aspect of the design phase and help the common user perform image analysis without the assistance of an expert.

There has been a recent uproar about falsified data in biomedical research. This occurs with some regularity, and even Congress has been aroused recently with the justification that the perpetrators and the universities where they worked had received public grant monies. The incidents may have been relatively few in numbers, but the fires have been fanned by the media. Less publicized, but perhaps more disturbing is the apparent conflict of interest spread by many new biotechnology companies. Researchers who develop and evaluate their products are frequently given substantial chunks of the companies whose products they are testing.

High Angle Dark Field Imaging, or Z contrast imaging, is an Imaging method. It takes advantage of the useful fact that if one uses the high angle scattering intensities and eliminates the elastic scattered (diffracted) beams from the image (by using a Howie type angular dark field detector), the remaining image will be characterized by, if the probe used is on the order of the atomic dimensions, intensity modulations that reveal atom positions and relative atomic number. In simple terms, the image will display Z-contrast at the atomic level and can differentiate columns of heavy atoms from columns of lighter ones.