The phrase "are maintained by different" is correct and usable in written English.
It can be used when discussing how various entities or systems keep or uphold certain standards, practices, or conditions.
Example: "The records are maintained by different departments to ensure accuracy and accountability."
Alternatives: "are upheld by various" or "are managed by distinct".
Although most Web sites are maintained by different agencies, some features are similar.
Seismic information is commonly shared across networks, and stored in heterogeneous databases that are maintained by different and autonomous groups.
There are a number of reasons why there can be a tax lot in PLUTO that does not match the DTM; the most common reason is that the various source files are maintained by different departments and divisions with varying update cycles and criteria for adding and removing records.
Currently at Partners, relevant terminology services are maintained by different teams.
To further complicate matters, murine studies have identified multiple pluripotent states that are maintained by different signalling networks [ 22].
Integrity and stability of the intestinal epithelium is maintained by different types of specialized cell contacts.
As the technique used has limited spatial resolution, the authors could only conclude that the processing of action words was maintained by "different parts of frontocentral cortex, possibly including the prefrontal, premotor and motor areas" ([23], p. 889).
Textbook knowledge indicates that the life of the cell is maintained by different organelles and proteins which have different functions.
Methylation of CG and CWG sites is maintained by different mechanisms: CG sites are maintained by a plant homolog of mammalian Dnmt1 acting on hemi-methylated DNA after replication [ 57] whereas methylation of CNG sites (N is any nucleotide) is maintained by other mechanisms.
They are expected to be maintained by different means of reproductive isolation that prevent the minority cytotype from losing too many gametes in crosses with the majority cytotype, which eventually would lead to its extirpation (minority cytotype exclusion principle; Levin, 1975; Husband, 2000).
