| Feature | Low-Quality PDF (Dangerous) | High-Quality PDF (Essential) | | :--- | :--- | :--- | | | Blurry OCR (Optical Character Recognition) errors; "Bromelain" becomes "Brorneiain". | Vectorized or 300+ DPI scan; every chemical term is legible. | | Diagrams | Missing or pixelated charts. | Clear graphs showing enzyme activity vs. temperature/pH levels. | | References | Citations missing or links broken. | Hyperlinked footnotes to PubMed and Biblioteca Nacional de España . | | Formatting | Cut-off margins; lost paragraphs. | Preserved original layout; bookmarks for chapters. |