Résumé
Experiments were conducted to study sexual isolation among two natural populations of Drosophila ananassae maintained at 18 °C and 24 °C for 12 generations in the laboratory to see the effect of this environmental variable on behavioural isolation. Multiple choice technique was used and matings were observed directly in Elens Wattiaux mating chamber. Results showed sexual isolation among strains that were maintained at different temperatures, indicating that temperature may have affected the mating behaviour of the flies which resulted in the induction of ethological isolation among the strains.
Résumé
We quantified the combined effects of three food levels (0.01 X106, 0.1 X106 and 1.0X106 cells ml-1) and three temperature levels (15, 20 and 25oC) on the somatic and the clonal population growth of two cladocerans Ceriodaphnia dubia and Daphnia pulex for 24 to 42 days. The somatic growth data showed that both the cladoceran species began to increase their body size within 3 days and remained stable beyond a week. Food density had a significant effect on the body size of C. dubia while for D. pulex, food level and temperature as well as their interaction had significant effect on the body size. The population growth of both the cladoceran species was affected by temperature. At 15oC, C. dubia showed little growth at the highest food density, while at low food level, there was some increase in the population abundances, especially after a long lag phase of about 2 weeks. At 15oC and under the lowest tested food level, the population of D. pulex did not increase beyond the inoculation density. Optimal population growth of D. pulex was observed at intermediate temperature and at 1.0X106 cells ml-1 of food level while for C. dubia 25oC and the highest food level yielded highest growth. At low food level and low temperature, the rate of population increase (r) of C. dubia was much lower than that of D. pulex at comparable conditions. On the hand, at higher food levels and temperature regimes, the r of D. pulex was much higher than that of C.dubia. Regardless of the food levels and temperature, the r of C. dubia varied from 0.03 to 0.07 while that of D. pulex varied from 0.01 to 0.08 day-1.
Résumé
Un carbón bituminoso alto volátil del departamento de Cundinamarca (Colombia), se licuó en presencia de un catalizador polimetálico en un reactor discontinuo de 500 mL a 370, 410 y 450 °C, en atmósfera de hidrógeno, usando tetralina como solvente dador de hidrógeno y tiempo de residencia de 1 h. El uso del catalizador incrementó la conversión del carbón y el rendimiento hacia la fracción de aceites a medida que aumentó la temperatura. El máximo rendimiento a aceites obtenido fue del 67% a 450 °C.
A high volatile bituminous coal from the Department of Cundinamarca (Colombia), was liquefied in the presence of a polymetallic catalyst in a 500 mL batch reactor at 370, 410 and 450 °C under hydrogen atmosphere, using tetralin as hydrogen donor solvent and residence time of 1 h. When the catalyst was used and the temperature increased, the coal conversion and the oil yield increased too. The maximum oil yield obtained was 67% at 450 °C.
Um carvão betuminoso alto volátil do Departamento de Cundinamarca foi liquefeito na presença de um catalisador polimetálico num reactor de 500 mL a 370,410 e 450 °C em atmosfera de hidrogênio, usando tetralina como doador de hidrogênio do solvente e tempo de residencia de 1 h. O uso do catalisador aumentou a conversão do carvão e rendimento de óleo com o aumento da temperatura. O rendimento máximo de óleo obtido foi de 67% a 450 °C.
Résumé
This study focused on the evaluation of the specific biological heat potential (hb) of a food-processing artificial wastewater in the autothermal thermophilic aerobic treatment (ATAT) system. A novel experimental method was developed to evaluate the hb value by using the heat balance model under the steady state. This system was daily fed with oily and artificial wastewater at 21460 mg l-1 COD. The sludge retention time (SRT) was controlled at 15 days. The results showed that the average values of hb were 3.25 to 3.63 kcal g-1-COD-removed for the artificial wastewater. The values of true growth yield (Y0) were 0.08 to 0.19 mg-MLSS mg-1-COD for the food-processing wastewater at different temperatures. The COD removal efficiency was 77 to 91%, and it was decreased as temperature increased. But, the oil and grease (O and G) removal efficiency was 50 to 69%, and increased as temperature increased. These results might indicate that oil and grease become more soluble and accessible to microorganisms at high temperatures. The study indicated the temperature effect constant (Æ) of van’t Hoff- Arrhenius law was 0.958, which explained and showed typical characteristics in the low sludge yield of an ATAT process.
Résumé
Aiming to evaluate the effect of different temperatures of storage and bean genotypes, Phaseolus vulgaris L., on the expression of resistance to the bean weevil, Acanthoscelides obtectus (Say), tests were carried out with the genotypes Arc.1S, Arc.1, Arc.2, Arc.4 and Carioca Pitoco. Grains of Arc.1S and Arc.2 expressed resistance to A. obtectus at 20ºC, 25ºC and 30ºC; the resistance of Arc.1 was reduced as the storage temperature increased from 25ºC to 30ºC. The interaction genotypes x temperatures was significant, indicating that the increase of temperature affects the expression ofresistance. The 20ºC temperature was the most suitable to allow bean genotypes to be discriminate in terms of resistance.
Visando avaliar os efeitos de diferentes temperaturas de armazenamento e de genótipos de feijoeiro, Phaseolus vulgaris L., sobre a expressão da resistência ao caruncho, Acanthoscelides obtectus (Say), realizaram-se ensaios com os genótipos Arc.1S, Arc.1, Arc.2, Arc.4 e Carioca Pitoco. Os grãos de Arc.1S e Arc.2 expressaram resistência a A. obtectus nas temperaturas de 20ºC, 25ºC e 30°C; a resistência do genótipo Arc.1 diminuiu à medida que a temperatura de armazenamento foi elevada de 25ºC para 30ºC. A interação genótipos x temperaturas foi significativa, indicando que a elevação da temperatura afeta a expressão da resistência. A temperatura de 20ºC foi a mais adequada para discriminar os genótipos de feijoeiro, quanto a resistência.
Résumé
OBJECTIVE: To investigate the patterns of the temperature effect on motor nerve conduction parameters according to various warming methods and to obtain the most valuable method of warming in clinical setting. METHOD: Twenty normal subjects were studied. After limb cooling in cold water, the cooled hands were warmed by hot pack, fan heater, and whirl pool. The median motor responses were recorded at abdnctor pollicis brevis after the stimulation at the wrist during warming at 1 min interval until the temperature increment reached plateau. We measured the temperature changes and conduction parameters were measured at each examination. RESULTS: The time constants for temperature increment and distal motor latency, duration, area of compound muscle action potentials showed shorter tendency by hot pack and whirl pool than by fan heater (p<0.05). For the measurement of distal motor latency, time constant of whirl pool (2.49 1.21 min) was shorter than that of fan heater (7.12 3.12 min) or hot pack (5.96 1.98 min) (p<0.05). CONCLUSION: These findings suggest that the use of whirl pool is the most effective method for warming of the cooled limb.