164 research outputs found
Electrolytic removal of metals using a flow-through cell with a reticulated vitreous carbon cathode
The aim of the present study was to establish an electrolytic method for the removal of metals from wastewater using a three dimensional, reticulated vitreous carbon cathode. During the development of the experimental set up, particular attention was paid to the electrolyte flow rate and to the cathode porosity. The electrolytic cell employed potential values in such a way that the metals reduction reaction occurred under mass transport control. These potentials were determined by hydrodynamic voltammetry on a vitreous carbon rotating disc electrode. The cell proved to be efficient in removing copper, zinc and lead and it was able to reduce the levels of these metals from 50 mg/L to 0.1 mg/L.O objetivo do presente trabalho foi estabelecer um processo eletrolítico para remover metais de efluentes aquosos usando um catodo tridimensional de carbono vítreo reticulado. Durante o desenvolvimento do trabalho foi estudado a influência do fluxo do eletrólito e da porosidade do eletrodo. A célula eletrolítica utilizou potenciais tais que a reação de redução ocorreu sob controle de transporte de massa. A célula demonstrou eficiência na remoção de chumbo, zinco e cobre, reduzindo a concentração desses metais de 50 mg.L-1 a 0,1 mg.L-1 em 20 min de recirculação da solução.48749
Species of Bursaphelenchus Fuchs, 1937 (Nematoda: Parasitaphelenchidae) and other nematode genera associated with insects from Pinus pinaster in Portugal
Insects associated with maritime pine, Pinus pinaster, in Portugal were collected
and screened for the presence of Bursaphelenchus species. Nematodes were
identified using Internal Transcribed Spacers-Restriction Fragment Length
Polymorphism (ITS-RFLP) analysis of dauer juveniles and morphological
identification of adults that developed from dauer juveniles on fungal cultures
or on cultures in pine wood segments at 26 C. Several associations are
described: Bursaphelenchus teratospicularis and Bursaphelenchus sexdentati are
associated with Orthotomicus erosus; Bursaphelenchus tusciae, B. sexdentati and/or
Bursaphelenchus pinophilus with Hylurgus ligniperda and Bursaphelenchus hellenicus
with Tomicus piniperda, Ips sexdentatus and H. ligniperda. An unidentified
Bursaphelenchus species is vectored by Hylobius sp. The previously reported
association of Bursaphelenchus xylophilus with Monochamus galloprovincialis
was confirmed. The association of Bursaphelenchus leoni with Pityogenes sp. is
not definitively established and needs further studies for clarification.
Other nematode genera besides Bursaphelenchus were found to be associated
with the insects sampled, including two different species of Ektaphelenchus, Parasitorhabditis
sp., Parasitaphelenchus sp., Contortylenchus sp. and other unidentified
nematodes. The Ektaphelenchus species found in O. erosus is morphologically
similar to B. teratospicularis found in the same insect; adults of both the species
are found in cocoon-like structures under the elytra of the insects.
Introduction
Approximately one third of the nematodes belonging to
the order Aphelenchida Siddiqi, 1980 are associated with
insects (Poinar, 1983). These nematodes establish a variety
of associations with the insects, which may be
described as commensalism, e.g. phoresy (to the benefit
of the nematode but not affecting the insect), mutualism
(both the organisms benefit) or parasitism (nematodes
benefit at the expense of the insect) (Giblin-Davis,
2004).
Most Bursaphelenchus Fuchs, 1937 species are mycetophagous,
feeding on fungi in the galleries of bark beetles
and thu
Antihypertensive therapeutic potential of citronellal
Cardiovascular effects induced by citronellal in rats were investigated in this study. In LNAME hypertensive rats, the oral acute administration of citronellal (200 mg/kg) was able to significantly reduce the blood pressure. In normotensive rats, citronellal (5-40 mg/kg, i.v.) induced hypotension, which was not affected by pre-treatment with atropine, hexamethonium, L-NAME or indomethacin, and bradycardia, which was abolished by atropine and hexamethonium, but not by L-NAME or indomethacin. ECG records revealed that citronellal induced sinoatrial block, which was abolished after atropine. In intact rings of rat mesenteric artery pre-contracted with phenylephrine (10 μM), citronellal (10 –6 to 10 –1 M) was able to induce relaxations (Emax = 106.3 ± 9.4 %) that were not affected by endothelium removal or after pre-contraction with KCl 80 mM. In conclusion, these results demonstrate that citronellal reduces blood pressure. Furthermore, citronellal induces endothelium-independent vasorelaxation in rat artery that appears to involve inhibition of Ca2+ influx.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Hypoglycemic activity of polysaccharide fractions containing ß-glucans from extracts of Rhynchelytrum repens (Willd.) C.E. Hubb., Poaceae
Escherichia coli and Salmonella ser. Saintpaul natural co-infection in a free-living ruddy ground dove (Columbina talpacoti): a case report
Influência da cobertura vegetal do solo na qualidade dos frutos de videira 'Niagara Rosada'
Efeito de óleos essenciais como alternativa no controle de Colletotrichum gloeosporioides, em pimenta
Interação genótipo x ambiente e estimativas de parâmetros genéticos dos pesos aos 205 e 365 dias de idade de bovinos Nelore
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