RESUMO
Short-term and long-term effects of Cd(II) on wastewater biological nitrogen and phosphorus removal were investigated with respect to microorganism abundances, enzyme activities, and polyhydroxyalkanoates (PHAs) and glycogen transformations. Though no obvious effects on wastewater biological nutrient removal were observed after short-term exposure, the long-term exposure of 10 mg L(-)(1) Cd(II) inhibited nitrification and phosphorus uptake. Compared with the absence of Cd(II), the presence of 10 mg L(-1) of Cd(II) decreased total nitrogen and phosphorus removal efficiencies from 97% and 98% to 88% and 18%, respectively. Mechanism studies revealed that Cd(II) affected the transformations of intracellular PHAs and glycogen, and the activities of oxidoreductase and polyphosphate kinase, resulted in the decrease of nitrite oxidizing bacteria and polyphosphate accumulating organisms abundance, which might be the major reason for the negative effects of long-term exposure to 10 mg L(-1) Cd(II) on biological nitrogen and phosphorus removal.
Assuntos
Bactérias/efeitos dos fármacos , Compostos de Cádmio/toxicidade , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Águas Residuárias , Poluentes Químicos da Água/toxicidade , Purificação da Água/métodos , Aerobiose , Anaerobiose , Bactérias/enzimologia , Compostos de Cádmio/análise , Nitrificação , Esgotos/microbiologia , Águas Residuárias/química , Águas Residuárias/microbiologia , Poluentes Químicos da Água/análiseRESUMO
OBJECTIVE: To observe the distribution of the blood vessels in the integument tissue of the channel area of legs. METHODS: The integument tissue of the lower limbs in the 12 cadavers were dissected with macro-and micro-dissection, radiographical technique of systemic artery and technique of image pattern analysis to observe and analyze the origins, branches and anastomoses in the integument tissues along the channels of legs. RESULTS: The distributional density of the blood vessels in the integument tissues of legs along the channel area of the three-yin meridians of the foot, the Gallbladder Meridian, and the Urinary Bladder Meridian was higher than that in the other parts. They formed an obvious nutrient vascular chain on the arteriogram. The distributional density in the channel area of the Stomach Meridian was not obviously increased and the obvious nutrient vascular chain could not be seen. CONCLUSION: An obvious nutrient vascular chain is formed in the integument tissue along the channel area of legs except the Stomach Meridian.