## Problem 050 — rank:62

**Title:** Cell–cell signalling inference

**Added binding assumptions (LaTeX):**

```latex
For the corrected transport-then-binding model, positions and cell types are fixed on the observation window and receptor availability is evaluated at reception time $t$. Moving cells require a space--time kernel. If $K$ instead includes receptor-memory or downstream signaling, specify that full state law rather than placing the receptor factor at an unexplained time. Expression-only data do not identify secretion or receptor occupancy without their measurement model.
```

**Direct edits:** 1. **Fresh external checks:** None; supplied sources retained as provenance.