Magnitude Of Temperature Decrease Research Articles

Thoracotomy for lung lesion does not affect the accuracy of esophageal temperature

BackgroundThere are several sites for measuring body temperature. Correct reading of core temperature is imperative for patients undergoing major operations under anesthesia. In certain situations, the sites of measurement may be close to the surgical area, and thus the measurement is easily prejudiced by the influence environment. We hypothesized that the body temperature, if monitored in the esophagus, would be lower than obtained from the tympanic membrane during thoracotomy for lung pathology under general anesthesia. Materials and methodsThe study involved 32 patients, of American Society of Anesthesiologists (ASA) physical status I or II, who were to undergo elective thoracotomy for lung disorders. General anesthesia was induced with fentanyl, propofol, and rocuronium and maintained with sevoflurane in oxygen. The tympanic membrane probe was placed prior to when general anesthesia was administered, and the esophageal probe was inserted after administration of general anesthesia. Both the individualized temperatures were recorded at 5-minute intervals, and were compared at each change of surgical situation. ResultsThe tympanic membrane temperature was higher than esophageal temperature after initiation of one-lung ventilation (OLV) with statistical significance. The magnitude of decrease in temperature between two individualized temperatures, as compared from start of OLV, was greater in tympanic membrane temperature, especially at 30 minutes after OLV (p < 0.02, difference = –0.09 ± 0.22) and at the time point of the lowest temperature (p = 0.002, difference = −0.14 ± 0.24). There was no clinical difference of situation found (difference > 0.5°C) in the measuring sequences. ConclusionThe accuracy of esophageal temperature seemed not to be affected during thoracotomy for lung lesion, in comparison with that of tympanic temperature. From clinical viewpoints, the monitoring of esophageal temperature could be more reliable in such surgical situation.

Temperature variation in liquid infiltration and defiltration in a MCM41

In a calometric measurement of infiltration and defiltration of pressurized liquid in a hydrophobic MCM41, it is observed that in nanopores the energy change between solid and liquid phases is dependent on the direction of liquid motion: liquid infiltration is exothermic and liquid defiltration is endothermic. The sorption curves and the temperature variation are insensitive to the loading rate. The magnitude of temperature decrease in defiltration is smaller than the temperature increase in infiltration, fitting well with the hysteresis of the sorption curve. These phenomena can be attributed to the confinement effect of nanopore walls and the thermally/mechanically aided surface diffusion of liquid molecules.

On the magnitude of temperature decrease in the equatorial regions during the Last Glacial Maximum

On the magnitude of temperature decrease in the equatorial regions during the Last Glacial Maximum

On the magnitude of temperature decrease in the equatorial regions during the Last Glacial Maximum

Based on the data of temperature changes revealed by means of various palaeothermometric proxy indices, it is found that the magnitude of temperature decrease became large with altitude in the equatorial regions during the Last Glacial Maximum. The direct cause of this phenomenon was the change in temperature lapse rate, which was about (0.1 ±0.05)℃/100 m larger in the equator during the Last Glacial Maximum than at present. Moreover, the analyses show that CLIMAP possibly underestimated the sea surface temperature decrease in the equatorial regions during the Last Glacial Maximum.