Maya calendar the land of Yucatán into 13 'kingdoms'. 1897 text by Cyrus Thomas Maya calendar The Maya calendar is a system of calendars used in pre-Columbian Mesoamerica and in many modern communities in the Guatemalan highlands, Veracruz, Oaxaca and Chiapas, Mexico. The essentials of the Maya calendar are based upon a system which had been in common use throughout the region, dating back to at least the 5th century BCE. It shares many aspects with calendars employed by other earlier Mesoamerican civilizations, such as the Zapotec and Olmec and contemporary or later ones such as the Mixtec and Aztec calendars. By
Mesoamerican nephropathy the same fashion or quantities as in Mesoamerica. However, heat stress measurements have not been assessed in these countries and cannot be compared, and CKD cases could be underreported, just like in the Mesoamerican region before the first description of the disease back in 2002. In any case, there are important differences between these Caribbean and Atlantic countries and the Mesoamerican Pacific coastlands, differences including A large (nearly 38,000 workers, 5 year follow up) prospective study of occupational heat stress and Kidney Disease from Thailand in 2012 found a 5-fold increased risk (adjusted odds ratio) for CKD in heat stress