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Sanches E.A.,Sao Paulo State University | Caneppele D.,Companhia Energetica de Sao Paulo CESP | Okawara R.Y.,Consultoria Tecnica em Aquicultura MPA | Damasceno D.Z.,Sao Paulo State University | And 2 more authors.
Neotropical Ichthyology | Year: 2016

The Steindachneridion parahybae is an endangered catfish from Brazil and strategies applied for gametes optimization are necessary. The aim of this study was to assess inseminating doses and water volume upon the fertilization, hatching rates and percentage of normal larvae in S. parahybae. Was used a randomized design in factorial scheme (4×4) with four inseminating doses: 1.0×104, 1.0×105, 1.0×106, 1.0×107 spermatozoa oocyte-1 and four volumes of water: 1, 35, 65 and 95mL of water g-1 of oocytes. The combination of doses and volumes were performed in triplicates (n=48). Each incubator (1.5L of useful volume) with 1g of oocytes was considered as an experimental unit. Significant interaction between inseminating doses and volumes of water to the values of the fertilization rates and quadratic effect of doses and volume for the values of hatching rates were observed. The doses and volumes did not influence the percentage of normal larvae (87.70±5.06%). It is recommended the use of 5.5×106 spermatozoa oocyte-1 and 1mL of water g-1 of oocytes during in vitro fertilization procedure. These results allowed us to develop new biotechnological strategies applied to the conservation of S. parahybae. © 2016, Sociedade Brasileira de Ictiologia. All rights reserved. Source

Honji R.M.,University of Sao Paulo | Tolussi C.E.,University of Sao Paulo | Mello P.H.,University of Sao Paulo | Caneppele D.,Companhia Energetica de Sao Paulo CESP | Moreira R.G.,University of Sao Paulo
Neotropical Ichthyology | Year: 2012

Steindachneridion parahybae is a freshwater catfish endemic to the Paraíba do Sul River and is classified as an endangered Neotropical species. An increasing number of conservation biologists are incorporating morphological and physiological research data to help conservation managers in rescue these endangered species. This study investigated the embryonic and larval development of S. parahybae in captivity, with emphasis in major events during the ontogeny of S. parahybae. Broodstocks were artificially induced to reproduce, and the extrusion occurred 200-255 degree-hours after hormonal induction at 24°C. Larval ontogeny was evaluated every 10 minutes under microscopic/stereomicroscopic using fresh eggs samples. The main embryogenic development stages were identified: zygote, cleavage, including the morula, blastula, gastrula phase, organogenesis, and hatching. The extruded oocytes showed an average diameter of 1.10 ± 0.10 mm, and after fertilization and hydration of eggs, the average diameter of eggs increased to about 1.90 ± 0.60 mm, characterized by a large perivitelline space that persisted up to embryo development, the double chorion, and the poles (animal and vegetative). Cell division started about 2 minutes after fertilization (AF), resulting in 2, 4, 8 (4 × 2 arrangement of cells), 16 (4 × 4), 32 (4 × 8) and 64 (2 × 4 × 8) cells. Furthermore, the blastula and gastrula stages followed after these cells divisions. The closed blastopore occurred at 11 h 20 min AF; following the development, the organogenetic stages were identified and subdivided respectively in: early segmentation phase and late segmentation phase. In the early segmentation phase, there was the establishment of the embryonic axis, and it was possible to distinguish between the cephalic and caudal regions; somites, and the optic vesicles developed about 20 h AF. Total hatching occurred at 54 h AF, and the larvae average length was 4.30 ± 0.70 mm. Gradual yolk sac reduction was observed during the first two days of larval development. The first feeding occurred at the end of the second day. During the larval phase, cannibalism, heterogeneous larval growth and photophobia were also observed. This information will be important in improving the artificial reproduction protocols of S. parahybae in controlled breeding programs. © 2012 Sociedade Brasileira de Ictiologia. Source

Andrade J.G.P.,University of Campinas | Barbosa P.S.F.,University of Campinas | Luvizotto E.,University of Campinas | Zuculin S.,Companhia Energetica de Sao Paulo CESP | And 2 more authors.
IOP Conference Series: Earth and Environmental Science | Year: 2014

The energy generated by wind or solar photovoltaic (PV system) can be used by PSP to accumulate water in the upper reservoir, in the form of potential energy to be used later, during periods of high energy demand. This procedure offers the advantage of enabling the use of intermittent renewable energy source in times of growing needs of the electric power supply. The location of the PSP, the environmental aspects involved, their possible use for various purposes (stability of the power system at peak times, associate the turbine water for public supply purposes, among others) and the discussion of regulatory issues needs to be debated in the current context, where environmental issues require reliable sources of power generation and demand shows strong growth rates. A dynamic model is used to analyze the behavior of a PSP proposal for a site in Brazil, analyzing a complete cycle of its operation as a pump or turbine. The existing difficulties to use this proposal based on existing regulatory policies are also discussed, and a list of recommended adjustments is provided to allow the penetrations of PSP projects in the Brazilian institutional framework, coupled with other intermittent energy sources. © Published under licence by IOP Publishing Ltd. Source

Ferreira D.G.,State University Londrina | Souza-Shibatta L.,State University Londrina | Shibatta O.A.,State University Londrina | Sofia S.H.,State University Londrina | And 4 more authors.
Reviews in Fish Biology and Fisheries | Year: 2016

Over the past few decades, South American Rivers, including the Paraná River system, have been intensely impacted by dam constructions. To mitigate adverse impacts, fish passages were incorporated into two large dams on the Paraná River (Itaipu and Porto Primavera) to reestablish longitudinal connectivity, which is very important for conserving populations of migratory fish species. The aim of this study was to estimate genetic diversity, population differentiation and gene flow, using microsatellites markers and mitochondrial haplotypes (d-loop), in populations of Prochilodus lineatus, a long distance migratory species commonly found in Paraná River basin drainages. Samples were obtained from six locations in the Upper and Middle Paraná River: Porto Primavera Reservoir, downstream of the Porto Primavera Reservoir, four tributaries of this reservoir (Pardo, Peixe, Verde and Aguapeí Rivers) and in the Iguaçu River, downstream of the Itaipu dam. High genetic diversity was observed in all samples, as expected for species with large population sizes and high migration rates. However, the influence of other factors, such as secondary contacts, fish passages and restocking were also suggested. In general, evidence of spatial population structuring was not found, even though there were two large dams in the study area. This could also be attributed to the brief period that has elapsed since the dams were built, the influence of migratory and reproductive patterns and the possible contributory effects of the fish passages. Furthermore, the absence of population structuring also corroborates existing information that emphasizes the importance of unimpeded tributaries for conserving migratory fish populations in fragmented watersheds. © 2016 Springer International Publishing Switzerland Source

Sousa T.,FDTE Foundation for the Technological Development of the Engineering Sciences | Tahan C.M.V.,FDTE Foundation for the Technological Development of the Engineering Sciences | Jardini J.A.,FDTE Foundation for the Technological Development of the Engineering Sciences | Rosa J.A.D.O.,Companhia Energetica de Sao Paulo CESP | And 2 more authors.
IEEE Latin America Transactions | Year: 2010

The restructuring of electrical sector based on the market resulted in the separation of generation, transmission and distribution agents and in the operation costs discrimination. This process lead to the necessity to separate the different services provided by the agents with the objective of organize by function and to define methodologies to identify who offers and who uses these services, as well as methodologies of remuneration to same ones. In this way, the present work presenting studies and methodologies to remunerate some Ancillary Services, such as: Black-start, Active Power Reserve, Special Protection Systems and Reactive Power Support. The studies and methodologies proposed were accomplished starting from the Ancillary Services provided by large Brazilian generation agents. Source

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