"expands upon earlier" is a perfectly correct and usable phrase in written English.
You can use it to describe an idea, event, or concept that goes further than a previous one. For example, "The new treaty expands upon earlier agreements by strengthening environmental protection regulations."
This work expands upon earlier implementations by incorporating voltage magnitudes and reactive power into the system model utilized by MPC.
The new doorman program expands upon earlier presentations that she gave to a human resources class for doormen sponsored by their union.
The legislation expands upon earlier "crack house" laws, allowing authorities to crack down events that "knowingly and intentionally" encourage drug use.
This investigation expands upon earlier work studying the association of hypoglycemia with mortality in the critically ill.
This observation is in agreement with and expands upon earlier reports of noise-induced increases in cleaved caspase-9 (CC9) and EndoG translocation.
We analyze previously unpublished data to refine and expand upon earlier hypotheses regarding implications for hominin anatomy and social behavior.
The findings expand upon earlier research that associates maternal obesity with a number of negative developmental effects.
A recent poll by the National Academy for Social Insurance (NASI) reinforced and expanded upon earlier poll findings when it showed that, by large majorities, Americans would rather raise taxes -- including on themselves - in order to expand Social Security's benefits.
Importantly, this study incorporates institution-dwelling OSC and longitudinal follow-up to expand upon earlier studies in the POFO population.
We expand upon earlier studies to show that mitochondria donate their membranes to form autophagosomes during basal and drug-induced autophagy.
Our study also included extra-gonadal GCTs and a large series of ovarian GCTs of different histological types, and therefore we were able to expand upon earlier findings in these tumours.
