Spatial structure is sometimes abstracted into a general network of interactions. The journal is abstracted and indexed in PubMed, Meta, and Scopus. The journal is abstracted and indexed in EBSCO's Business Source Complete database. The syntax of Z39.50 is abstracted from the underlying database structure. In nearly all artistic media, simpler shapes were adopted and once natural designs were abstracted. The concept of surface has been abstracted and formalized in mathematics, specifically in geometry. Objects are broken up, analyzed, and re-assembled in an abstracted form. The direct product can be abstracted to an arbitrary category. The study of kinship may be abstracted to binary relations between people. Complex service-assemblies are abstracted behind simple URI interfaces. Scales can be abstracted from performance or composition. Depending on the interpretation of the following verse, Muslim scholars have abstracted different opinions. These are usually abstracted as point-like particles, even though they have volumes, shapes, structures, etc. In general, methyl and methylene H atoms are abstracted much more easily than methine hydrogens. This bidirectional data flow can be abstracted with an ordinary serial line.