Greening the operating room.

BACKGROUND: Climate change will affect most populations in the next decades and put the health of billions of people at risk. Health care facilities represent a significant source of pollution around the world and contribute to environmental changes. To address this topic, we performed a review of the available literature on tactics to reduce operating room (OR) waste and the potential of these strategies to impact the environment. DATA SOURCES: A literature search was performed querying PubMed, Web of Science, and Science Direct. No comparative data were found; most were opinion papers, white papers, and case studies. For this reason, we proceeded with a narrative review, which provides an overview of the evidence on this topic and identifies areas for future research. RESULTS: This systematic review summarizes the available literature on the 5 "Rs" of waste management: reduction, reusing, recycling, rethinking, and renewable energies. CONCLUSIONS: Surgery has a unique opportunity to transition to more environmentally-friendly operating room strategies, which may help decrease waste and lessen the impact of climate change.

Mathematical accuracy of Aztec land surveys assessed from records in the Codex Vergara.

Land surveying in ancient states is documented not only for Eurasia but also for the Americas, amply attested by two Acolhua-Aztec pictorial manuscripts from the Valley of Mexico. The Codex Vergara and the Códice de Santa María Asunción consist of hundreds of drawings of agricultural fields that uniquely record surface areas as well as perimeter measurements. A previous study of the Codex Vergara examines how Acolhua-Aztecs determined field area by reconstructing their calculation procedures. Here we evaluate the accuracy of their area values using modern mathematics. The findings verify the overall mathematical validity of the codex records. Three-quarters of the areas are within 5% of the maximum possible value, and 85% are within 10%, which compares well with reported errors by Western surveyors that postdate Aztec-Acolhua work by several centuries.