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Gomes P.C.,Instituto Agronomico Do Parana | Lopera-Barrero N.M.,State University Londrina | Vargas L.,State University of Maringa | Streit Junior D.P.,Federal University of Rio Grande do Sul | And 3 more authors.
Semina:Ciencias Agrarias | Year: 2013

The aim of this study was to evaluate the genetic diversity of Salminus brasiliensis collected three times in the passage ladder of the hydropower plant Canoas I, in the Paranapanema River (Brazil). Fish samples were collected on 14 (CI14), 18 (CI18) and 25 (CI25) February 2008. Eight primers using RAPD technique were evaluated. Seventy-nine in 105 fragments amplified using these primers were polymorphic fragments (75.2%), 32 had frequencies with significant differences (P<0.05), 10 had low frequencies, 25 were excluded, and four were fixed fragments. One exclusive fragment was found in the CI14 sample. High values for polymorphic fragments and genetic diversity index of Shannon were observed for the CI14 and CI18. Low ancestry levels among the groups were indicated by the FST values that indicated high genetic differentiation. In all the three groups, the estimates of the number of migrants by generation (Nm) indicated low levels of gene flow. Most of the genetic variation was found within the groups through the AMOVA analysis, which was confirmed by the results of the identity and genetic distance. The results indicate high variability within the groups and genetic differentiation among them. Source

de Almeida F.S.,State University Londrina | Lopes C.M.,Federal University of Rio Grande do Sul | Orsi M.L.,State University Londrina | Sirol R.N.,Companhia Paulista de Forca e Luz | Sodre L.M.K.,State University Londrina
Acta Scientiarum - Animal Sciences | Year: 2013

The preservation of the genetic variability of hatchery stocks used to supplement natural populations is a priority. Current study employed RAPD markers to examine the genetic diversity of dourado samples from the middle Paranapanema river and from the broodstock used in the stock enhancement program of the Aquaculture and Hydrobiology Station at the Salto Grande Hydroelectric Power Plant. Nineteen RAPD primers were analyzed, which generated 299 bands and the latter were used for genetic analysis. The percentage of polymorphic fragments was higher in stock captured in the Paranapanema river than from fry stocks. The genetic diversity was lower in the broodstock than in natural population. Amova results showed that most interpopulation genetic variation lay within stocks (83.9%) and not between them (16.1%). Moderate genetic differentiation (FST = 0.16) was reported. Nevertheless, differentiation decreased when the four fry stocks were mixed and analyzed as a single population (FST = 0.07). Instead of releasing each lot separately into the water, mixing specimens produced in the various fry stocks before releasing them in the river would be more feasible. The restocked population will have a genetic structure closer to natural populations. Source

Lopera-Barrero N.M.,State University Londrina | Alvarez C.A.R.,National University of La Plata | Del Pilar Rodriguez-Rodriguez M.,State University of Maringa | Povh J.A.,Federal University of Mato Grosso do Sul | And 2 more authors.
Semina:Ciencias Agrarias | Year: 2014

The objective of this study was to estimate the genetic diversity and the paternity of Brycon orbignyanus offspring's obtained with the extrusion and semi-natural reproductive systems, by microsatellites markers. The four loci used produced 11 alleles, being observed three alleles (BoM1, BoM5 and BoM7) and two alleles (BoM2) for locus present in the parental and in the offspring of both reproductive systems. In the offspring of the extrusion system low frequency alleles was observed for the locus BoM5 (allele B = 0.095) and BoM7 (allele C = 0.059) and there was a decrease of genetic variability (observe heterozygosity-Ho = 0.900 and 0.823; Shannon index-IS = 0.937 and 0.886; Nei genetic diversity-DGN = 0.604 and 0.566, respectively). For the offspring of the semi-natural system the allele frequencies stayed stable being verified an unequal frequency for each locus. The genetic variability in the offspring was preserved, being corroborated by the Ho values (0.975 and 0.945), IS (0.927 and 0.924) and DGN (0.593 and 0.581) for parental and offspring, respectively. Deviations were observed (P <0.01) in the Hardy-Weinberg equilibrium and linkage disequilibrium for the two reproductive systems. The inbreeding coefficient (Fis) it showed deficit of heterozygote in the offspring of the extrusion system. Multiple paternity and differed reproductive contributions in the composition of the families in the offspring in the two reproductive systems was observed, with the presence of reproductive dominance in the semi-natural system. Source

Fornari D.C.,Federal University of Rio Grande do Sul | Streit D.P.,Federal University of Rio Grande do Sul | Tonissi L.B.,Profissional Liberal | Povh J.A.,Federal University of Mato Grosso do Sul | And 2 more authors.
Semina:Ciencias Agrarias | Year: 2014

The aim of this study was to evaluate cryoprotectants for cooling embryos of B. orbignyanus. 1400 embryos were selected, in the post-gastrulation and subjected to cooling to -8°C with different combinations of intracellular cryoprotectants (methanol and 9% DMSO or associated 4.5%) combined with extracellular cryoprotectants (sucrose and glucose, 17%) diluted in distilled water to complete 100%. For each treatment, 200 embryos were placed in glass tubes and submitted to the cooling process. After the proposed time, the embryos were removed and transferred to four-liter incubation to hatching of the larvae. The results obtained from solutions containing glucose were inefficient. The treatments with association of DMSO showed no satisfactory results. For cooling of B. orbignyanus embryos at -8°C it is suggested to use a cryoprotectant solution containing 17% sucrose associated with 9% methanol. Source

Matsuo I.B.M.,University of Sao Paulo | Jardini J.A.,University of Sao Paulo | Hokama W.S.,Companhia Paulista de Forca e Luz
IEEE Latin America Transactions | Year: 2015

It is important that electrical networks have high levels of reliability in order to maintain the ideal agility and maintenance for better functioning. This fact combined with the increasing amount of information available in modern digital relays advances the idea of implementing systems that assist achieve fast and correct decisions on the protection system functioning. The purpose of this project was to implement a system that responds in an automated manner to protection-related events in distribution substations, providing a quick and complete diagnosis. The work has two foci. The first is the communication system based on an IEC61850/OPC server and the process automation through a client program. The second is an expert system that analyzes protection-related events based on data collected from the relays. An important result was the possibility of generating a correct diagnosis based on different data sets. This is extremely important, since one cannot expect exactly the same set of information for analysis, which should not prevent the delivery of a diagnosis. This system was installed in a substation of Companhia Paulista de Força e Luz, a Brazilian power distribution utility. © 2015 IEEE. Source

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