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Studies of the tissues of the human olfactory mucosa have been performed to investigate olfactory dysfunction and, more recently, olfactory mucosa has attracted a novel interest of investigators because it can be used as an early marker of neurodegenerative conditions of the brain and as a source of multipotent neural stem cells, with applications in regenerative medicine. The olfactory mucosa is readily available to the otolaryngologist, but the harvesting of this tissue must be safe, effective, and reliable, obtaining as little tissue as necessary, while avoiding unnecessary harm to the remaining olfactory tissue and function. The purpose of this review is to summarize the results of the most important studies and knowledge with regard to the human olfactory mucosa and its applications, emphasizing the issue of the distribution of the olfactory mucosa in the nasal cavities. [ABSTRACT FROM AUTHOR]

Abstract: A series of HBEA samples were prepared by dealumination through steaming or treatment by hydrochloric acid of a parent commercial zeolite. Treatments with acid solutions were shown to cause a rapid dissolution of the extraframework Al (EFAL) species, especially the monomeric ones and a slow dissolution of the framework Al (FAL) atoms of bridging OH groups and structure defects. Steaming at high temperatures (500–700 °C) causes both an extraction of FAL atoms and a significant increase in the degree of polymerization of the EFAL species. A quantitative distribution of the various Al species of the parent HBEA zeolite was established. The nature of the hydroxylated Al species responsible for the IR bands in the OH region was specified: the band at 3607 cm–1 was ascribed to bridging OH groups responsible for the Brønsted acidity, that at 3660 cm–1 to monomeric and polymeric EFAL species, that at 3680 cm–1 to hydroxylated EFAL clusters resulting from acid extraction of Lewis framework defects; that at 3780 cm–1 to both monomeric EFAL species and framework defects with Lewis acidity. To cite this article: F.R. Ribeiro and al., C. R. Chimie 8 (2005). [Copyright &y& Elsevier]