Domain: Healthcare — Pathophysiology
Target concept: Jaundice in Hepatic Failure

Video generation prompt: Injecting carbon tetrachloride (a hepatotoxin) into rabbits, observe changes in the color of the sclera and skin, and measure serum bilirubin levels.

Evaluation guide:
(i) Target concept: Hepatotoxin-induced jaundice as a visual biomarker of hepatic failure, depicted as a symbolic time-lapse compression of a process that in reality takes roughly one to three days to become visible after a single carbon tetrachloride injection; the video is not meant to depict real elapsed time, but to compress the injection and the resulting scleral/skin/serum yellowing into one illustrative sequence.
Minimum mechanism: Carbon tetrachloride must be administered *first*; the yellowing of sclera, skin, and serum must appear only afterward, standing in for the multi-day interval during which hepatocellular injury impairs bilirubin conjugation and clearance, requiring intact ocular anatomy, functional dermal translucency, and serum protein binding capacity, even though the video itself compresses that interval.
(ii)Storyline (time-lapse compression: on-screen duration does not represent real elapsed time): [Segment 1] Rabbit at rest, sclera white, skin pink, syringe approaches flank. [Segment 2] Syringe needle contacts and inserts into the flank (visible skin indentation); this stands in for the CCl4 injection that in reality precedes visible jaundice by roughly one to three days. [Segment 3, marked as a later time-lapse stage via a fade, dissolve, or other explicit visual cue] Sclera begins yellowing at the inner canthus and spreads outward; skin yellowing appears on the pinnae. [Segment 4] A serum vial enters frame holding yellow-tinged liquid. Across segments, the rabbit, syringe/vial, and sclera/skin keep a consistent relative composition and lighting within each segment, but a clearly marked time-lapse transition (not a literal unbroken instant) separates the injection from the later yellowing, so the compressed timeline reads as intentional rather than implying jaundice appears within seconds of injection.

Manual:
Experimental Procedure
1. Inject carbon tetrachloride solution into rabbit"s flank using sterile syringe.
2. Observe sclera and skin for yellow discoloration.
3. Collect serum sample and place in transparent vial.
Observation of Experimental Phenomena
- Sclera changes from white to uniform yellow.
- Skin (especially pinnae and abdomen) changes from pink to uniform yellow.
- Serum in vial appears pale-to-moderate yellow-tinged, translucent.
Summary of Experimental Principles
Carbon tetrachloride induces hepatocellular necrosis → impaired bilirubin conjugation and excretion → accumulation of unconjugated and conjugated bilirubin → yellow pigmentation of sclera/skin (jaundice) and yellow serum (hyperbilirubinemia).

Prompt Grounding rubric:
level_1: No rabbit appears anywhere in the clip; no injection action is ever shown; the sclera and skin are never visible; no serum vial or blood-sample container appears; none of the three core elements (rabbit, syringe, serum vial) show up at all.
level_2: A rabbit is shown but nothing ever touches it; or a syringe appears but never makes contact with the rabbit's flank; or sclera and skin are visible but no injection is ever depicted; or a vial appears with no visual link to a blood or serum sample.
level_3: The rabbit is shown with a syringe contacting its flank; the sclera and skin are visible in that segment or a later one; a serum vial also appears somewhere in the clip; a clearly marked time-lapse transition (such as a fade or dissolve) separates the injection moment from a later observation moment, rather than everything being crammed into one implausibly short continuous take.
level_4: Everything required for score 3 holds, and in addition the syringe visibly punctures the flank rather than just resting against the skin, the serum vial appears in the segment that comes after the injection (not before it), and the transition marking the jump from the injection moment to the later stage is visually legible rather than an abrupt, unexplained cut to an unrelated-looking scene.
level_5: Everything required for score 4 holds, and in addition the rabbit, syringe, and serum vial keep the same relative arrangement (which side of the frame each one is on) across the injection segment and the later segment, the serum vial is clearly recognizable as a blood-derived sample (e.g., labeled or held in a way consistent with a lab sample), and the time-lapse marker is clear enough that a viewer can tell the later segment represents a later point in time rather than the next few seconds.

Scientific and Causal Correctness rubric:
level_1: No causal link appears at all: the sclera and skin stay white and pink for the entire clip; no yellow tint ever shows up; the serum vial holds a clear or reddish liquid instead of anything yellow-tinged; the injection has no visible effect on any of these features.
level_2: Yellow coloration shows up before the injection happens, or with no connection to it at all (e.g., the rabbit already looks jaundiced at the start); the serum vial holds an obviously non-biological liquid such as plain water or a blue or green dye; or the sclera and skin turn an incorrect color such as purple, gray, or green rather than yellow.
level_3: Yellow discoloration only appears in the segment that follows the injection, never before it; the sclera and skin both take on a fairly even yellow tone rather than looking blotchy, orange, or red; the serum vial holds a translucent, yellow-tinged liquid consistent with a bilirubin rise; the sequence reads as: injection, then later yellowing of sclera and skin, then yellow-tinged serum.
level_4: Building on the 3-point bar, the yellow intensity of the sclera is roughly in line with the yellow intensity of the skin, without one looking far more saturated than the other; the serum vial's liquid is an even yellow with no visible sediment, layering, or cloudiness that would be out of place for dissolved bilirubin; nothing in the scene contradicts liver failure: for instance, the rabbit isn't shown with healthy pink mucous membranes or otherwise normal coloring elsewhere while its sclera reads yellow.
level_5: Building on the 4-point bar, the yellowing visibly starts near the inner corner of the eye and spreads outward across the sclera, and on the skin it shows up most clearly on the ears, matching the pattern typically seen in rabbit models; the serum in the vial looks pale-to-moderate yellow rather than deep amber or brown, consistent with a moderate bilirubin elevation; no unrelated color change (such as a bluish tinge, paleness, or reddening) appears anywhere that would contradict the jaundice/liver-failure picture.

Spatiotemporal Consistency rubric:
level_1: The rabbit seems to vanish and come back as a different animal or in an unrelated pose with nothing visually connecting the two; the syringe jumps to a new position with no motion at all; the segment showing yellowing uses such a different camera angle, framing, or rabbit pose that it's unclear it's even the same rabbit; the serum vial simply appears in frame with no hand or motion bringing it in; the lighting jumps from bright to dark, or a shadow snaps to a new direction, with nothing in the scene to explain it.
level_2: The rabbit, syringe, and later scene are recognizably connected, but the switch from the injection moment to the later yellowing/serum moment is an unmarked hard cut rather than a clear fade, dissolve, or other time cue, so it reads like an editing mistake instead of an intentional time jump; the close-up of the sclera and the full-body shot of the rabbit use such different zoom levels that the rabbit looks like a different size across the cut; the serum vial enters with unnatural motion (floating in, spinning, or scaling up abruptly); the lighting shifts abruptly within what's supposed to be a single continuous moment.
level_3: Within each segment of the clip, the rabbit, syringe, and serum vial keep the same relative arrangement (rabbit centered, syringe approaching from one side, vial appearing later without switching sides); nothing vanishes or teleports within a segment; the syringe's approach to the flank is one smooth, continuous motion ending in contact, not a jump; the switch from the injection segment to the later yellowing segment is marked clearly enough (a fade, dissolve, or similar cue) that it reads as an intentional time jump rather than a broken cut; the rabbit's body shape and proportions stay consistent and undistorted throughout.
level_4: Building on the 3-point bar, the syringe's approach to the flank follows a smooth, direct path with no hesitation, reversal, or overshoot; once the time-lapse cue moves the video into the later segment, the yellowing of sclera and skin is shown building up gradually across that segment rather than snapping instantly from white/pink to full yellow; the serum vial stays still and fully visible once it enters the frame; the lighting within each individual segment stays steady rather than flickering or shifting from moment to moment.
level_5: Building on the 4-point bar, the camera framing within each segment stays fixed, with no noticeable pan, tilt, zoom, or dolly; the rabbit shows small signs of being a live animal (subtle body movement) in the earlier segment; the syringe's puncture of the flank causes a brief, localized dimple in the skin that settles back smoothly; the yellow coloration in the later segment builds up gradually across that segment rather than jumping straight to its final shade within a single frame.