How much less likely is it that someone who is not a resident of Paris, working in an academic or medical field, is to know what the acronyms mean?
Surely one could take a guess from looking at "Assistance Publique–Hopitaux de Paris (AP–HP)", what "AP-HP" might mean?
1. Go to Google
2. Type in Hôpitaux de Paris (AP-HP). The circonflexe and the parentheses can be omitted.
3. Study the hits.
4. Surmise from the summaries that AP may stand for Assistance Publique.
5. Notice likewise that HP may stand for Hôpitaux de Paris.
6. Further notice that there is listed, not very far fromthe top, a Wikipedia entry in English for "Assistance Publique – Hôpitaux de Paris".
7. Read the summary at the top of the entry which says:
"The Assistance publique – Hôpitaux de Paris (AP-HP) is the public hospital system (établissement public de santé) of the city of Paris and its suburbs. Its headquarters are in the 4th arrondissement of Paris.
It is the largest hospital system in Europe and one of the largest in the world, it provides health care, teaching, research, prevention, education and emergency medical service in 52 branches of medicine. It employs more than 90,000 people (including 15,800 physicians) in 44 hospitals and receives more than 5.8 million annual patient visits.
The AP-HP is linked with the University of Paris and its seven colleges of medicine, two of odontology and two of pharmacy."
8. Possibly read the rest of the entry.
9. Repeat for UPMC Paris and discover what Université de Paris Pierre et Marie Curie is.