RESUMO
Objective To investigate the characteristic of growth and development of vegetable at hypobaric environment and offer the cultivating technique of controlled ecological life support system for higher plant.Methods The means of comparative measurement was adopted to study the growth and physiological characteristic of lettuce under low and normal pressure(40.0 kPa,101.0 kPa),which was carried out with the low pressure plant-cultivating facility.Results Compared with normal pressure,germination rate of lettuce seed was eliminated by 7.62% under total pressure 40.0 kPa and oxygen partial pressure 8.4 kPa conditions;harvest time of lettuce was delayed,so biomass harvested at the same time reduced by 13.67% and content of total saccharide declined;the average rates of photosynthesis and transpiration were lower than those at normal pressure in 30 days after planting(DAP),but which reversed after that;release of C2H4 and shoot height reduced by 38.79% and 11.68%,but leaf area,ratio of root to total biomass and root vigor increased by 15.43%,2.57% and 40.53%,respectively.Conclusion Seed germination,growth and development of lettuce are affected in some degree at total pressure 40.0 kPa and oxygen partial pressure 8.4 kPa,some measures should be adopted to regulate the growth of lettuce.
RESUMO
La hipoxia secundaria al ambiente -hipobárico de la altura tiene un efecto sobre la saturación arterial de oxígeno. Material y método: se determinó hematocrito y gases sanguíneos en sangre arterial radial derecha de niños sanos de 7 a 14 días de edad, nacidos de madres que cursaron embarazo y parto en la altura (3.600 metros sobre el nivel del mar). Objetivo: determinar saturación arterial de oxígeno en niños sanos de 7 a 14 días de edad, nacidos a 3.600 metros sobre el nivel del mar. Resultados: en una muestra de 60 niños, el hematocrito fue de 50 ± 7,64, similar al encontrado a nivel del mar. La saturación de oxígeno, de 85,34 ± 10,45 comparada con valores de 95 ± 5 encontrados a nivel del mar; es significativamente más baja (p< 0,001) Discusión: se debe tomar en cuenta este valor de referencia de saturación de oxígeno en el tratamiento de niños de edad neonatal en la altura, particularmente si tienen una patología que puede alterar la saturación de oxígeno.
Hypoxia secondary to the hypobaric environment at high altitude has an effect on blood gases. Methods: packed red cell volume (PRC) and blood gases were measured on arterial blood obtained from the right radial artery from healthy children 7 to 14 days old, born of mothers who underwent pregnancy and delivery at high altitude (3,600 meters above sea level). Objective: to determine arterial oxygen saturation in healthy children 7 to 14 days of age, born at 3600 meters above sea level. Results: in a sample of 60 infants, PRC was 50 ± 7,64, similar to the values described at sea level. Oxygen saturation was 85,34 ± 10,45; compared to 95 ± 5 at sea level. The difference was statistically significant (p< 0,001) Discussion: these reference values have to be taken into account when treating young infants at high altitude, particularly those that have an illness that can modify oxygen saturation.