This LaTeX source code does not contain a research paper. Rather, it defines a large number of journal options that can be passed to the \DeclareOption command.
Specifically, it allows an author to specify a journal name, which will then automatically set various macros used for typesetting papers for that journal, such as:
- @journalfull: The full journal name
- @journalshort: The short journal name/abbreviation
- @doiabbr: The abbreviation used in DOIs for that journal
- @ISSN: The ISSN number for the journal
- @continuouspages: Whether to number pages continuously across articles
So in summary, this code defines journal metadata and typesetting options for many MDPI journals to facilitate preparing papers for submission to those journals. There is no main contribution or research content.