Afro-textured hair chart below is the most commonly used chart to help determine hair types: Different ethnic groups have observable differences in the structure, density, and growth rate of hair. With regard to structure, all human hair has the same basic chemical composition in terms of keratin protein content. Franbourg "et al." have found that Black hair may differ in the distribution of lipids throughout the hair shaft. Classical afro-textured hair has been found to be not as densely concentrated on the scalp as other follical types. Specifically, the average density of afro-textured hair was found to be approximately 190 hairs per
Protein A due to the high purity and yield which are achieved in a easily and reliably achieved. This forms the basis for a general antibody purification "platform" which simplifies manufacturing operations and reduces the time and effort required to develop purification processes. A typical mAb purification process is shown at right. Albeit the long history of protein A chromatography for the production of antibodies, the process is still being improved today. Continuous chromatography, more precisely periodic counter-current chromatography, enormously increases the productivity of the purification step. Protein A Protein A is a 42 kDa surface protein originally found in the cell