Domain: Healthcare — Pathology
Target concept: Cellular Injury (Hypoxic Injury)

Video generation prompt: Cells were incubated in an oxygen-free buffer and continuously observed under a light microscope for morphological changes.

Evaluation guide:
(i) Target concept: Cellular morphological response to acute oxygen deprivation.
Minimum mechanism: Cells must be metabolically active at baseline, immersed in an inert, non-hypotonic, non-toxic oxygen-free aqueous buffer, with no external energy input or chemical perturbation; injury must arise solely from ATP depletion-induced ion pump failure.
(ii)Storyline: Frame 1: Static microscope view showing healthy adherent or suspended cells with crisp edges and granular cytoplasm in clear buffer inside sealed chamber. Frame 2–3: Cells retain position but begin losing edge definition; cytoplasm appears less granular, more homogeneous. Frame 4–5: Clear emergence of intracellular vacuoles; cells become more spherical. Frame 6–10: Progressive rounding and generalized swelling; membranes remain intact but increasingly blurred, with no lysis, no movement, no color change. Perspective: Fixed-stage, high-magnification, brightfield microscopy view; entire sequence must occur within same focal plane and field-of-view without camera motion or focus shift.

Manual:
Experimental Procedure
1. Place cultured mammalian cells into a sealed chamber filled with oxygen-free buffer.
2. Mount chamber on light microscope stage and focus on a representative field of cells.
3. Observe continuously for morphological changes over time.
Observation of Experimental Phenomena
Healthy cells appear phase-bright with sharp borders and granular cytoplasm; under hypoxia, they progressively swell, lose refractility, develop cytoplasmic vacuoles, and round up — all while remaining intact and motionless.
Summary of Experimental Principles
Hypoxic injury depletes ATP, impairing Na+/K+ pumps → osmotic swelling → loss of microvilli and organelle integrity → cytoplasmic vacuolation → eventual membrane failure.

Prompt Grounding rubric:
level_1: No sealed incubation chamber is visible; no oxygen-free buffer is shown; no cells appear in the microscope view; there is no indication of continuous or time-lapse observation.
level_2: Only some of the required elements appear together incorrectly: e.g., cells are shown without any buffer or chamber, a buffer-filled chamber appears with no cells inside, or the microscope view shows objects unrelated to cells in buffer.
level_3: A sealed chamber holding oxygen-free buffer is visible, cells are suspended or adherent within that buffer, and this is all shown within one static brightfield microscope field of view; the objects are correctly co-located, though no time progression is shown yet.
level_4: Everything in score 3 holds, and additionally the video shows the same field of view across time: an early frame shows cells with sharp, well-defined borders, and later frames show the same cells (not replaced, not repositioned) with less-defined borders, consistent with real-time observation under a fixed microscope view.
level_5: Everything in score 4 holds, and additionally the cells' appearance changes continuously within this single, unbroken shot: no cut, zoom, pan, or camera/focus change occurs at any point, and no extraneous labels, timestamps, or overlays are added to the microscope image.

Scientific and Causal Correctness rubric:
level_1: The cells show no visible change in appearance across the whole video, or they change in ways inconsistent with hypoxic injury (e.g., cells vanish, divide, burst apart suddenly, or turn an unnatural color such as blue or red); or the buffer itself changes color or clarity, implying no causal link between the absence of oxygen and any change in the cells.
level_2: Cells do change, but in ways that contradict ATP-depletion injury: e.g., cells shrink and become shriveled (an apoptotic/necrotic pattern, not swelling), cells rupture apart almost instantly rather than gradually, or cells actively move around the field (motility requires ATP, which should be depleted); or the buffer visibly bubbles or evaporates, which is inconsistent with a sealed anaerobic chamber.
level_3: Cells progressively deteriorate while staying fully immersed in the still buffer: an early frame shows intact plasma membranes with granular cytoplasm, and a later frame shows reduced refractility, visible cytoplasmic vacuoles, and more rounded cell shape; there is no cell division, no active movement, and no artificial staining involved.
level_4: Everything in score 3 holds, and additionally the changes occur in the expected order for hypoxic injury (swelling and rounding appear before vacuoles form, and vacuoles form before membrane definition blurs further), with no recovery or re-sharpening of the cells at any point; features specific to a different injury pathway, such as chromatin condensation or nuclear fragmentation (which mark apoptosis rather than hypoxic/ischemic injury), are absent.
level_5: Everything in score 4 holds, and additionally every visible change traces back to the lack of oxygen: the buffer stays clear and motionless throughout with no visible convection currents, the cells never actively move or crawl, and the deterioration matches textbook reversible hypoxic injury (cell and organelle swelling, loss of surface microvilli, membrane blebbing, and cytoplasmic vacuolation are all consistent with this), with no sign of osmotic-shock artifacts, pH-driven swelling, or heat-induced distortion.

Spatiotemporal Consistency rubric:
level_1: Cells suddenly jump to different positions between frames; the video cuts from bright to completely dark with no transition; the chamber disappears and reappears; or the microscope view suddenly rotates or flips.
level_2: The video flickers or strobes repeatedly; frames are duplicated or skipped enough to make the motion jerky; compression artifacts visibly distort the cells' shape between frames; or the cast shadow on the chamber wall changes direction from one frame to the next with nothing to explain why.
level_3: The chamber's edges stay fixed in the frame, and the cells keep the same positions relative to each other and to the chamber walls; the direction and brightness of the light on the chamber stay the same throughout; no cell breaks apart and reassembles.
level_4: Everything in score 3 holds, and additionally cell swelling looks like smooth, rounded expansion with no jagged or broken cell boundary appearing during the growth; vacuoles appear gradually inside the cell body rather than suddenly at the cell edge; the buffer surface stays flat and undisturbed, without ripples or flow patterns that a static, sealed incubation would not produce.
level_5: Everything in score 4 holds, and additionally there is no ghosting trail behind moving cell boundaries, no motion blur implausible at this magnification, no shift in relative position between the chamber wall and the cells, all cells stay in the same focus plane throughout, and the swelling progression plays out smoothly with no strobing or freeze-frame effect.