|
|
|
| Registros recuperados: 36 | |
|
|
| Carvalho,Luciana R. de; Sant'Anna,Célia L.; Gemelgo,Marcina C.P.; Azevedo,Maria Teresa de P.. |
| Billings and Guarapiranga Reservoirs were deeply affected by environmental disturbances, which more evident consequence are the cyanobacterial blooms. Microcystins are the most common cyanotoxin in freshwaters and more than 70 types are known. Different methods for microcystins analysis in water can be used, among which ELISA and HPLC are the most frequently employed. However, less sophisticated and more economic methods can also be used. This is the case of planar chromatography (thin-layer chromatography) method previously used in cyanotoxins purification but gradually replaced by others. Posterior optimization of the microcystin chromatography conditions and because of its simplicity, rapidity, efficiency and low cost, this method is again considered an... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cyanobacteria; Drinking water; Microcystins; Planar chromatography; Reservoirs. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-84042007000100014 |
| |
|
|
| Duarte,Silvana; Araújo,Francisco Gerson; Bazzoli,Nilo. |
| In this work we describe the gonad morphology and spawning season of Hypostomus affinis (Steindachner, 1877) in a tropical reservoir based on 55 males and 125 females. Our aim was to assess eventual adaptations in reproductive tactics developed by this riverine species inhabiting an oligotrophic reservoir with low habitat complexity, few rocks and few other preferred consolidated substrata. We described the stages of cells of reproductive lineage, gonadal development and some reproductive traits which were compared with information in the available literature. Cells from the spermatogenic lineage were spermatogonia, spermatocytes, spermatids and spermatozoa, and cells from the oocytarian lineage were primary oocytes, previtelogenic oocytes, cortical... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Brazil; Fish reproduction; Reproductive biology; Reservoirs; Tactics. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000500005 |
| |
|
|
| Duarte,Silvana; Paiva,Marco A. R.; Lara,Camila C.; Bemquerer,Marcelo P.; Araújo,Francisco Gerson. |
| The enzymatic activities involved in the digestion of proteins and carbohydrates were compared among three organs of the digestive track of two Siluriformes fish species, and between two areas: a reservoir, and an area downriver of it. Our aim was to test the hypothesis that the digestive organs of species with varied feeding habits have different enzymatic activities, and that the enzymatic activity differs among seasons and environmental conditions. The iliophagous/herbivorous species Hypostomus auroguttatus Kner, 1854 had higher trypsin-like, chymotrypsin-like peptidase and β-glucosidase activity in the intestine when compared with the omnivorous species Pimelodus maculatus Lacepède, 1803, whereas the latter had more hepatic trypsin-like activity than... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Enzymatic activity; Fishes; Physiology; Reservoirs; Siluriformes; Peptidases; Β-glucosidase. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702013000300006 |
| |
|
|
| Perbiche-Neves,Gilmar; Rocha,Carlos E.F. da; Nogueira,Marcos G.. |
| Species richness and geographical distribution of Cyclopoida freshwater copepods were analyzed along the "La Plata" River basin. Ninety-six samples were taken from 24 sampling sites, twelve sites for zooplankton in open waters and twelve sites for zooplankton within macrophyte stands, including reservoirs and lotic stretches. There were, on average, three species per sample in the plankton compared to five per sample in macrophytes. Six species were exclusive to the plankton, 10 to macrophyte stands, and 17 were common to both. Only one species was found in similar proportions in plankton and macrophytes, while five species were widely found in plankton, and thirteen in macrophytes. The distinction between species from open water zooplankton and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: La Plata River basin; Reservoirs; Rivers; Zooplankton. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702014000300005 |
| |
|
|
| Santos,Júlio César Neves dos; Andrade,Eunice Maia de; Araújo Neto,José Ribeiro de; Meireles,Ana Célia Maia; Palácio,Helba Araújo de Queiroz. |
| Water body eutrophication process has been a serious problem around the world, especially in semiarid and arid region where main approach to storage water is reservoir. The aim of this work was to investigate the spatial and seasonal variability in water quality of a reservoir in a semi-arid tropical region with regards to its trophic state, and to identify the sources of nutrient input to the reservoir. Essa pesquisa foi realizada no reservatório Orós, segundo maior do estado do Ceará-Brasil. This research was developed in the Orós reservoir, the second one most important reservoir in Ceará State, Brazil. Samples were collected bimonthly during the period April 2008 to April 2010, from sex sampling points representing the outlet of tributaries, and one... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water resources; Reservoirs; Water quality. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902014000100005 |
| |
|
|
| Santos,Luciano Neves dos; Gonzalez,Alejandra Filippo; Araújo,Francisco Gerson. |
| The diet of Cichla monoculus (Bloch & Schneider, 1801) in Lajes's Reservoir, a major impoundment in Rio de Janeiro State, Brazil, was assessed, from fishes collected in 1994,1996 and 1999/2000. Gut contents in individuals was analyzed by the index of relative importance (IRI) which deals with numerical, gravimetrical and frequency of occurrence. Cichla monoculus showed a strong piscivorous habits feeding on Cichlidae, Characidae and Pimelodidae, in decreasing order of importance, with a remarkable cannibalism on young-of-the-year. Others minor items in the diet were Macrobrachium sp. and Odonata. Changes in feeding composition varied with reservoir's zones and seasons, with higher diversity in Autumn and peaks of cannibalism in lower zone during... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cichla; Trofic ecology; Diet; Reservoirs; Freshwater fish; Condition factor; Feeding habits. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752001000500015 |
| |
|
| |
|
|
| Goes Filho,Adbeel. |
| This paper presents the practical application of concepts, and some methods of risk analysis, to check the possibility of overcoming a water level of project in the spillway of dam Orós, by excess of influent flow. Also evaluated the empirical formulas contained in the original design. Due to the difficulty of obtaining design data from the dam, since the end of construction date of January, 11, 1961, we minimize the effects of some variables in the calculations, leading us to the consequent simplification of the scenario under study. For a better evaluation and characterization of the setting, some variables in the model such as water level, accumulation and flow of the spillway, had updated their data to June 28, 2011. We have demonstrated the importance... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Risk analysis; Public dams; Reservoirs; Water resources management. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000100405 |
| |
|
| |
|
|
| Martins,Isabela; Sanches,Barbara; Kaufmann,Philip Robert; Hughes,Robert M.; Santos,Gilmar Bastos; Molozzi,Joseline; Callisto,Marcos. |
| Reservoirs are artificial ecosystems with multiple functions having direct and indirect benefits to humans; however, they also cause ecological changes and influence the composition and structure of aquatic biota. Our objectives were to: (1) assess the environmental condition of Nova Ponte Reservoir, Minas Gerais state, southeastern Brazil; and (2) determine how the aquatic biota respond to disturbances. A total of 40 sites in the littoral zone of the reservoir were sampled to characterize physical and chemical habitat, land use, and benthic macroinvertebrate and fish assemblages. The predominant type of land cover near the reservoir was natural vegetation. A total of 29 fish species and 39 macroinvertebrate taxa were collected, including eight alien... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Reservoirs; Water quality; Bioindicators; Physical habitat; Environmental quality. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032015000100103 |
| |
|
| |
|
| |
|
|
| ESPÍNDOLA,E. L. G.; MATSUMURA-TUNDISI,T.; RIETZLER,A. C.; TUNDISI,J. G.. |
| With the purpose of analyzing the horizontal distribution of the zooplankton community of the Tucuruí Reservoir in the State of Pará, Brazil, collections were made at 16 stations during August 1988. The stations cover the regions called Caraipé (C), Araçagi (B) and Ararão (A), and represent the different compartments of this ecosystem in regard to the morphometry and the presence or absence of "flooded forest". Our findings showed the existence of three compartments with different limnological characteristics determined as a function of the system's morphometry, a factor that may have influenced the horizontal circulation of the reservoir's water and, consequently, led to physical, chemical and biological differences at each of the sampled stations. All... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Zooplankton; Horizontal distribution; Spatial heterogeneity; Reservoirs. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0034-71082000000200001 |
| |
|
| |
|
|
| Dorneles,Elaine Maria Seles; Pellegrin,Aiesca Oliveira; Péres,Igor Alexandre Hany Fuzeta Schabib; Mathias,Luis Antônio; Mourão,Guilherme; Bianchi,Rita de Cassia; Olifiers,Natalie; Rocha,Fabiana Lopes; Lage,Andrey Pereira. |
| A serological survey in free-ranging crab-eating foxes (Canidae: Cerdocyon thous) and brown-nosed coatis (Procyonidae: Nasua nasua) was performed in the Nhecolândia sub-region of the Brazilian Pantanal to evaluate the presence of anti-smooth Brucella antibodies on those wild populations. The detection of anti-smooth Brucella antibodies was performed by the Rose Bengal Test (RBT) as screening test and the Fluorescence Polarization Assay (FPA) as a confirmatory test. The frequency of smooth Brucella seropositive animals were 13.2% (5/38, 95% CI: 4.4% - 28.1%) for crab-eating foxes and 8.8% (3/34, 95% CI: 1.9% -23.7%) for brown-nosed coatis. No association was found between seropositivity for brucellosis and gender or age. The results of this study suggest... |
| Tipo: Info:eu-repo/semantics/report |
Palavras-chave: Brazil; Brucella; Pantanal; Cerdocyon thous; Nasua nasua; Reservoirs; Epidemiology. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782014001202193 |
| |
|
|
| Toledo,Zorayda; Simaluiza,Rosa Janneth; Fernández,Heriberto. |
| ABSTRACT: Occurrence and antimicrobial resistance profiles of Campylobacter jejuni and C. coli strains isolated from fecal samples of dogs, pigs, cows and hens in southern Ecuador were studied. Of the 250 samples studied, 84 (33.6%) were Campylobacter positive, with C. jejuni being more frequent (78.6%) than C. coli (21.4%), with the exception of porcine samples, from which C. coli was the only species isolated. Multidrug resistance was reported in 10 Campylobacter strains (11.9%), four C. jejuni and six C. coli, and was always associated with nalidixic acid and ciprofloxacin resistance. All of the amoxicillin-resistant strains were susceptible to amoxicillin-clavulanic acid and were therefore beta-lactamase producers. However, one strain of C. jejuni... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Campylobacter; Reservoirs; Domestic animals; Antimicrobial resistance. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018001100450 |
| |
| Registros recuperados: 36 | |
|
|
|
