The phrase "are often modified by" is correct and usable in written English.
It can be used when discussing how certain elements, such as words or phrases, can be changed or adjusted by other elements in a sentence or context.
Example: "In English grammar, adjectives are often modified by adverbs to provide more detail."
Alternatives: "are frequently altered by" or "are commonly adjusted by".
Temperatures are often modified by sea winds.
Additionally, those proteins are often modified by the covalent attachment of hydrocarbon chains.
Applied clays and clay minerals are often modified by cation exchange with inorganic cations (soda- and acid-activation) and organic cations, mainly long-chain alkylammonium ions.
An acquired character is a response to the environment; an inherited character is produced by genes transmitted from parent to offspring (their expressions are often modified by environmental conditions).
Polymer surfaces are often modified by thin layers of protein-like collagen or fibronectin to improve their biocompatibility [14].
Primary transcript RNAs are often modified by enzymes after transcription.
To increase its activity and stability, this basic catalyst was often modified by different oxide additives.
Ultimately what it shows is this: that the idealism of the founding generation was sometimes compromised by a fair measure of cynicism; that compassion was often modified by calculated self-interest; that tolerance and decency sometimes were replaced by callous narrow-mindedness and ugly expediency.
The carboxy-terminal CCVM motif of PRL-3 belongs to a broad class of proteins containing a CAAX motif, which is often modified by post-prenylation.
DNA of prokaryotic and eukaryotic cells and their viruses is often modified by methylation, carried out by S-adenosyl-L-methionine (AdoMet -dependent DNAdoMet -dependentses (MTases).
These tags are often modified or removed by some post-processing software, DICOM-not-compliant software, or during anonymization of the patient data in DICOM.
