Domain: Healthcare — Pathophysiology
Target concept: Coagulative necrotic myocardial tissue

Video generation prompt: A tissue section of coagulative necrosis of myocardium, stained with hematoxylin and eosin, was placed on the experimental table for observation of myocardial cell morphology under a light microscope.

Evaluation guide:
(i) Target concept: Histologic identification of coagulative necrosis in myocardium via H&E-stained light microscopy.
Minimum mechanism: Ischemic insult → protein denaturation → preservation of tissue scaffold → cellular detail loss → characteristic staining shift (hypereosinophilia) + nuclear degradation + sharp necrosis-viability interface.
(ii)Storyline: Frame 1–2: Static wide shot showing experimental table with H&E-stained myocardial tissue section centered. Frame 3–5: Cut or zoom to stable close-up of tissue section under microscope field-of-view, maintaining fixed viewpoint. Frame 6–10: Continuous observation of histologic features: (a) adjacent zones of viable myocardium (striated, pale pink cytoplasm, blue nuclei) and necrotic zone (non-striated, intense pink cytoplasm, shrunken/fragmented nuclei); (b) sharp demarcation between zones; (c) absence of inflammatory infiltrate or liquefaction. Perspective must be consistent with light microscope eyepiece view (flat 2D plane, no parallax, no depth cues beyond focus plane); all features must be fully in-focus and unoccluded.

Manual:
Experimental Procedure
1. Place H&E-stained myocardial tissue section flat on experimental table.
2. Position light microscope adjacent to slide, eyepiece facing observer.
3. Observe myocardial cell morphology under microscope.
Observation of Experimental Phenomena
- Myocardial tissue shows elongated, striated cardiomyocytes with central nuclei.
- Necrotic zone exhibits sharply demarcated, uniformly hyper-eosinophilic (intense pink) cytoplasm, loss of striations, and nuclear pyknosis/karyorrhexis.
- Viable myocardium adjacent shows normal striations and pale pink cytoplasm with distinct blue-purple nuclei.
Summary of Experimental Principles
Coagulative necrosis in myocardium results from ischemic injury causing denaturation of structural proteins; preserved tissue architecture with loss of cellular detail, characteristic H&E staining pattern (hypereosinophilia, nuclear disintegration), and sharp border with viable tissue.

Prompt Grounding rubric:
level_1: No tissue section visible; no microscope present; no experimental table shown; none of the required objects (myocardial tissue section, H&E-stained slide, light microscope, experimental table) appear.
level_2: At least one required object appears (e.g., a generic slide or microscope), but the myocardial tissue section is absent, unstained, or incorrectly labeled; placement on table is missing; observation action is not depicted.
level_3: All required objects are present: H&E-stained myocardial tissue section placed on experimental table, light microscope positioned adjacent to it; camera view shows both objects in same scene; no action sequence shown, but static composition satisfies prompt-specified setup.
level_4: All required objects present and correctly identified: H&E-stained myocardial tissue section placed centrally on experimental table, light microscope placed adjacent to it, eyepiece oriented toward viewer; the camera shows this wide setup, then transitions via a single cut or zoom to a stable close-up matching the microscope's eyepiece field of view, holding each viewpoint fixed without extra camera motion; no object enters/exits frame abruptly.
level_5: All required objects present, correctly identified, and spatially arranged as specified: tissue section placed flat on table surface, microscope placed adjacent (not overlapping), eyepiece aligned with viewer's implied line of sight; the camera holds the wide setup shot fixed, then makes one clean cut or smooth zoom to a stable close-up matching the microscope's eyepiece field of view and holds that viewpoint fixed for the remainder of the clip; no occlusion, no repositioning of the slide or microscope, no substitution (e.g., no digital overlay, no cartoon rendering).

Scientific and Causal Correctness rubric:
level_1: Tissue section shows no cellular morphology; color is monochromatic, non-H&E (e.g., all blue, all pink, grayscale, or unnatural hues); no myocardial architecture visible; no necrosis features present.
level_2: Section shows generic tissue structure but lacks myocardial specificity (e.g., no cross-striations, no intercalated discs, no cardiomyocyte shape); staining is partially H&E-like but misassigned (e.g., nuclei pink, cytoplasm blue); no coagulative necrosis features visible.
level_3: Section shows myocardial tissue architecture: elongated, striated cardiomyocytes with centrally located nuclei; H&E staining is broadly correct (nuclei blue-purple, cytoplasm pink-red); coagulative necrosis is indicated by at least one of the following: loss of striations, hypereosinophilia (intense uniform pink cytoplasm), nuclear pyknosis/karyorrhexis, or sharply demarcated necrotic zone; but not all features present or fully consistent.
level_4: Section shows myocardial tissue with correct architecture and H&E staining; coagulative necrosis is clearly present and fully consistent with pathophysiology: (a) sharply demarcated zone of necrosis adjacent to viable myocardium, (b) loss of cross-striations, (c) homogeneously hyper-eosinophilic (intense pink) cytoplasm, (d) nuclear changes (pyknosis, karyolysis, or karyorrhexis) visible; no contradictory features (e.g., neutrophil infiltration, liquefaction, or granulation tissue).
level_5: All four coagulative necrosis histopathological features fully present and unambiguously visible: (a) sharp interface between necrotic and viable myocardium, (b) complete loss of striations within necrotic zone, (c) uniform intense eosinophilia (pink) without vacuolization or granularity in necrotic myocytes, (d) definitive nuclear alterations (pyknosis OR karyorrhexis OR karyolysis) visible in ≥3 adjacent cardiomyocytes in necrotic zone; staining fidelity matches standard H&E reference: nuclei deep blue-purple, cytoplasm pale to medium pink, background near-white; zero contradictory histologic elements.

Spatiotemporal Consistency rubric:
level_1: Catastrophic spatiotemporal break: the myocardial tissue slide vanishes from the table and reappears in a different spot, or hovers above the table before snapping down onto it; the microscope's body spins a half-turn between one frame and the next; the room lighting strobes on and off repeatedly; the slide visibly splits into two pieces, or the edge of the table dissolves partway through the clip.
level_2: Several clearly visible breaks: the tissue slide slides sideways on the table with no hand or mechanism shown moving it; the microscope's eyepiece points a different direction than it did a moment earlier; the dark patch cast by the microscope's base relocates to the opposite side of the microscope while the room's light source stays in the same place; the tabletop surface bulges, warps, or momentarily disappears; the overall brightness of the scene jumps up or down more than twice during the clip.
level_3: One small flaw: for a brief, sub-second moment the myocardial tissue section is partly hidden by a hand or by the microscope's base before becoming fully visible again; or the edge of the slide lifts slightly off the table and then settles back flat; or the shadow beneath the microscope base looks briefly uneven without any other change. No slide or microscope ever disappears, duplicates, or changes position.
level_4: No object vanishes, duplicates, or changes position without cause; during the initial wide shot, the slide and microscope keep the same spatial relationship (microscope positioned beside the slide, eyepiece facing the viewer); the transition to the close-up eyepiece view is a single clean cut or smooth zoom, not a jarring cut with intermediate flickers; once in the close-up, the viewpoint holds fixed for the remainder of the clip; the shadow cast by the microscope base points the same direction throughout the wide shot; the myocardial tissue image shows no warping, stretching, or morphing; if the slide or microscope settles slightly at the start, that motion looks smooth and gradual rather than sudden.
level_5: The wide establishing shot and the close-up eyepiece shot are each perfectly steady, with no drift, jitter, or handheld shake within either shot; the single transition between them is a clean cut or smooth zoom with no visual glitch; the slide, microscope, and table stay fully visible and completely still throughout the wide shot, and the tissue image stays completely still throughout the close-up, with none of them changing position, size, or angle within a shot; the shadow beneath the microscope base and the overall brightness stay identical in direction and strength throughout the wide shot; there is no flicker, no shaking, and no stretching of the myocardial tissue image or slide edge, and no motion blur appears on objects that are supposed to be perfectly still.