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1.
Water Sci Technol ; 58(7): 1415-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18957754

RESUMO

This study attempted to investigate the impact of HRT of treated leachate recirculation on hydrolysis solubilization rate of coffee pulp in an acidogenic reactor. Coffee pulp presents more than 70% of organic matter and around of 30% of lignin and cellulose. Five lab scale reactors of 20 litres were used. Each reactor was fed with 5 kg of fresh coffee pulp and anaerobic sludge was used as inoculate. HRT of 0.5, 1, 3 and 10 days were applied. Each experiment shows that Total, Soluble and VFA COD appear rapidly in the removed leachate. HRT have a great impact on hydrolytic rate with an optimal value of 32,000 mg x L(-1) x d(-1).Low HRT increases hydrolysis rate and in consequence reduces duration of the hydrolytic phase. Also composition and concentration of VFA are influenced by HRT. Low ones favour acetic acid production and high ones permit the production of butyric. Low HRT generates leachate more easily fermentable. Efficiency of solubilization and acidification are independent of the HRT and present average values of 78% and 65% respectively. By batch feeding solid and continuous recirculation of treated leachate, HRT and SRT could be dissociated, where solid had a very high retention without problems of load, mixing and inhibition, and liquid could be recirculated with a very high rate. Under these low HRT condition, the first reactor of a two stage anaerobic system could reduces the hydrolysis duration of organic solid waste like coffee pulp and generate an optimal leachate for the methanization process.


Assuntos
Café/química , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Celulose/química , Celulose/metabolismo , Café/metabolismo , Hidrólise , Cinética , Lignina/química , Lignina/metabolismo , Esgotos/química , Esgotos/microbiologia , Solubilidade
2.
Pharmacol Biochem Behav ; 59(4): 903-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9586847

RESUMO

One-trial conditioning of the proboscis extension reflex (PER) in honeybees was used to examine the qualitative effects of two muscarinic antagonists, atropine and pirenzepine, on the acquisition and retrieval of memory following intracranial injection. The main result of this study is that atropine, at a relatively high concentration of 10(-2) M, impairs memory retrieval but not acquisition of memory after a single olfactory conditioning trial (at this concentration, there is no effect of atropine on the sensorimotor components of the PER). This result is in agreement with the effects of scopolamine, reported in a previously published article. Pirenzepine, at the same concentration as atropine, had no effect on either acquisition or retrieval of memory. These results suggest that blockade of muscarinic-like receptors, except those that bind to pirenzepine, induces solely an impairment of memory retrieval.


Assuntos
Atropina/farmacologia , Abelhas/fisiologia , Condicionamento Clássico/efeitos dos fármacos , Antagonistas Muscarínicos/farmacologia , Pirenzepina/farmacologia , Olfato/efeitos dos fármacos , Animais , Atropina/administração & dosagem , Encéfalo , Injeções , Antagonistas Muscarínicos/administração & dosagem , Pirenzepina/administração & dosagem , Reflexo/efeitos dos fármacos
3.
Behav Brain Res ; 63(2): 145-9, 1994 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-7999297

RESUMO

The role of the cholinergic system on learning abilities and memory performance has been investigated in the honeybee. The behavioural experiment was the olfactory conditioning of the proboscis extension reflex, elicited by an antennal sucrose stimulation. Intracranial scopolamine (0.5 mg/kg) or saline injections (0.25 microliter) were given at different times before or after a one trial learning session in order to interfere with acquisition of information, storage or recall processes. Neither scopolamine injections, ranging from 20 min to 5 min prior to the acquisition task, nor post-trial drug injections given in the same time-window, impaired the retention performance measured one hour after conditioning. Scopolamine injected 20 min after a learning session induced a time-dependent decrease of information retrieval, as was seen in retention testing performed from 5 min to one hour after injection. Then, the amnestic effect of intracranial scopolamine injection seems to be related to a specific and temporary inhibition of recall processes. We can conclude that, in the present task, muscarinic-like receptors are involved in information retrieval but not in acquisition or consolidation processes.


Assuntos
Abelhas/efeitos dos fármacos , Condicionamento Clássico/efeitos dos fármacos , Rememoração Mental/efeitos dos fármacos , Escopolamina/farmacologia , Olfato/efeitos dos fármacos , Animais , Comportamento Apetitivo/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Injeções , Receptores Colinérgicos/efeitos dos fármacos , Receptores Muscarínicos/efeitos dos fármacos , Retenção Psicológica/efeitos dos fármacos
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