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E A Roth

Publications and source records attributed to E A Roth.

20 records · Page 2Linked to original sources
PubMed1981

Demography and computer simulation in historic village population reconstruction.

"Demographic anthropology has given rise to methodological advances in the analysis of single community populations. However, the obstacles of small data bases and incomplete vital-event registration remain. This paper details one approach to these problems; the principles of community demography are incorporated with computer simulation methodology, with the goals of validating the internal consistency of and determining demographic secular trends from data commonly utilized in anthropological investigations." The approach is tested on data for the 250 inhabitants of Old Crow Village, Yukon Territory, Canada, in 1978.

Americas↗
PubMedDate not supplied

Severe local hypothermia from laparoscopic gas evaporative jet cooling: a mechanism to explain clinical observations.

BACKGROUND AND OBJECTIVES: Explanations for laparoscopic-induced hypothermia fail to explain clinical observations. It is possible that water evaporation occurs from the jet stream of gas inflation resulting in tissue surface super-cooling leading to tissue damage and drying. METHODS: Theoretical calculations based on thermal conductivity, mass transfer effects and heat flux considerations correlated closely with synthetic and tissue experiments. Thermocouple measurements at a rate of 15 data points per second were performed. RESULTS: Cooling rates of 10 to 25 degrees centigrade per second for high flow rates were found based on gas flow rate and effective size of gas delivery site. These rapid temperature drops extended beyond a 2 cm2 diameter. CONCLUSIONS: Evaporative cooling accounts for significant hypothermia. The cooling is dependent on the lack of water vapor in the gases currently used during laparoscopy. Cooling rates are independent of height from tissue and geometry of delivery port. Heating and hydrating the gas to a physiologic condition eliminates hypothermia and tissue dessication.

Culture Techniques↗