Domain: Healthcare — Microbiology-Immunology
Target concept: Vibrio cholerae Detection (Alkaline Peptone Water Colorimetric Method)

Video generation prompt: A technician prepared a test tube containing alkaline peptone water, inoculated it with a sample of Vibrio cholerae using a sterile loop, gently mixed the contents, and then placed the test tube in a 37°C incubator for enrichment culture.

Evaluation guide:
(i) Target concept: Visual verification of selective enrichment of Vibrio cholerae in alkaline peptone water via turbidity development.
Minimum mechanism: Bacterial growth must be represented solely by homogeneous, non-sedimenting turbidity in a pale yellow liquid medium, emerging only after several hours of incubation at 37°C, never within seconds of placement, and requiring prior inoculation, mixing, and an explicit time-lapse indicator to bridge the multi-hour gap.
(ii)Storyline: [Frame 0–2] Sterile loop approaches test tube containing pale yellow liquid → [Frame 3–4] Loop tip contacts liquid surface and withdraws → [Frame 5–6] Tube undergoes gentle swirling motion while held upright → [Frame 7] Tube is placed into incubator cavity and the door closes → [Time-lapse cue] An on-screen caption or dissolve transition marks several hours of elapsed incubation time (e.g., "6 hours later") → [Frame 8–9] When the tube is shown again, the liquid has transitioned from transparent pale yellow to uniformly cloudy (turbid); all events occur from a fixed frontal viewpoint with no occlusion and no unmarked cutaways; only the explicitly marked time-lapse break interrupts otherwise continuous, real-time viewing.

Manual:
Experimental Procedure
1. Hold sterile loop, dip into Vibrio cholerae sample, then transfer into alkaline peptone water in test tube.
2. Gently swirl tube to mix.
3. Place tube upright into 37°C incubator for several hours of enrichment.
Observation of Experimental Phenomena
Alkaline peptone water changes from clear pale yellow to uniformly turbid (cloudy) after several hours of incubation — the change is not visible within moments of placement and requires a depicted time-lapse to show.
Summary of Experimental Principles
Vibrio cholerae grows selectively in alkaline peptone water (pH 8.4–8.6), producing visible turbidity over several hours of incubation due to bacterial proliferation — a positive enrichment indicator.

Prompt Grounding rubric:
level_1: No test tube of liquid is shown; no sterile loop appears; no inoculation action is depicted; no incubator (or equivalent enclosed warming unit) appears at any point.
level_2: A liquid-filled tube, a loop-like tool, or an incubator-like unit appears, but the pieces don't connect to each other in the expected order: for example the tube goes into the incubator before the loop ever touches the liquid, or the loop appears with no matching tube of liquid.
level_3: A test tube holding liquid, a loop that visibly dips into and withdraws from that liquid, and an incubator that the tube is placed into all appear in the correct order: loop approaches the tube, loop touches the liquid, tube goes into the incubator.
level_4: Whatever earns a 3 is still present, and the loop looks clean going in (no visible residue on it beforehand), the tube stays upright and steady while being swirled, the incubator's door is shown closed once the tube is inside, and no unrelated props (gloves, labels, timers) dominate the shot.
level_5: Whatever earns a 4 is still present, and the loop only appears on screen during the inoculation step, the tube stays in the same spot on the bench before and after swirling, the tube goes straight into the incubator without being repositioned partway through, and the tube, loop, and incubator all look like the same objects (same shape, same color, same panel design) from the first frame they appear to the last.

Scientific and Causal Correctness rubric:
level_1: The liquid isn't pale yellow at the start, or it's already cloudy before any inoculation happens, or the loop deposits a colored clump or solid material rather than a clean liquid sample, or no turbidity ever develops even after a depicted time-lapse.
level_2: The liquid starts pale yellow and mixing is shown, but there's no time-lapse device at all before any implied turbidity: the tube looks cloudy within moments of being placed in the incubator, or the video ends right after placement with the liquid still unchanged and no cue that time has passed, leaving no way to judge whether the culture actually grew.
level_3: The liquid starts pale yellow; the loop makes clean contact and withdraws; some indicator of elapsed incubation time (a caption, a dissolve, or an equivalent time-skip cue) appears after the tube is placed in the incubator; when the tube is shown again, the liquid has become uniformly turbid; turbidity appears only after that marked time gap, not within moments of placement.
level_4: Everything required at the 3 level holds, and the turbidity is even throughout the liquid with no floating clumps, streaks, or a separate film on top; the liquid's base hue stays in the pale-yellow family rather than shifting to green, pink, or brown; no bubbling or gas pockets appear.
level_5: Everything required at the 4 level holds, and the turbidity looks even from the top of the liquid column to the bottom, with no clearly lighter or darker patch anywhere in the tube, and nothing (a floating layer, settled grains) suggests the sample separated into layers instead of clouding uniformly.

Spatiotemporal Consistency rubric:
level_1: The tube suddenly appears in a different spot or facing a different way than the moment before; the loop vanishes mid-motion and reappears somewhere else; the incubator changes size or shape between shots; the room lighting swings from bright to dark with no explanation.
level_2: The tube shakes hard during swirling and never settles; the loop's motion skips: it appears already inside the liquid without crossing the air-to-liquid boundary first; the incubator door opens or shuts at an unnaturally fast or jerky speed; a shadow cast by the tube or loop switches which way it falls between one moment and the next with nothing in the scene to explain it.
level_3: The tube, loop, and incubator stay visible throughout their relevant steps; the loop's approach, contact, and withdrawal read as one continuous motion; the tube sits still on the bench before being moved and sits still inside the incubator afterward; nothing flickers out of view or changes shape unexpectedly; the marked time-lapse break is the only interruption to otherwise continuous, real-time motion.
level_4: Everything required at the 3 level holds, and the swirling motion looks like a gentle rotation rather than shaking or tapping, the tube doesn't tip or spill while being swirled, the incubator's exterior door closes fully and smoothly, and there's no sudden viewpoint jump while the camera holds its position.
level_5: Everything required at the 4 level holds, and the loop keeps a steady angle relative to the tube through its entire approach-contact-withdrawal motion, the tube stays upright and centered before, during, and after swirling, the incubator door's closing motion doesn't reverse or stall partway, and the scene's perspective and proportions stay consistent from one moment to the next.