Genetic structuring and fixed polymorphisms in the gene period among natural populations of Lutzomyia longipalpis in Brazil

Citation: Costa, C. R. L., Freitas, M. T. D., Figueiredo, C. A. S., Aragao, N. C., da Silva, L. G., Marcondes, C. B., . . . Balbino, V. D. (2015). Genetic structuring and fixed polymorphisms in the gene period among natural populations of Lutzomyia longipalpis in Brazil. Parasites & Vectors, 8, 9. doi:10.1186/s13071-015-0785-6Background: Even one hundred years after being originally identified, aspects of the taxonomy of the sand fly Lutzomyia longipalpis, the principal vector of Leishmania infantum in the Americas, remain unresolved for Brazilian populations of this vector. The diversity of morphological, behavioral, biochemical, and ethological characters, as well as the genetic variability detected by molecular markers are indicative of the presence of a complex of species. Methods: In this study, a 525 bp fragment of the period gene was used to evaluate sympatric populations of L. longipalpis. A combination of probabilistic methods such as maximum likelihood and genetic assignment approach to investigate sympatric species of L. longipalpis were applied in three populations of Northeast Brazil. Results: Fixed polymorphisms in geographically isolated populations of L. longipalpis from two localities in the state of Ceara and one in the state of Pernambuco, Brazil, was identified in a 525 bp fragment of the gene period (per). Our results suggest a direct relationship between the number of spots found in males' tergites and the genetic variation in cryptic species of L. longipalpis. The fragment used in this study revealed the nature of the ancestral morphotype 1S. Conclusion: New polymorphisms were identified in the gene per which can be used as a genetic barcode to sympatric taxonomy of L. longipalpis. The per gene fragment confirmed the presence of two siblings species of L. longipalpis in Sobral and showed that these same species are present in two other localities, representing an expansion within the L. longipalpis species complex with regards to the states of Ceara and Pernambuco

Relações entre gênese de solos halomórficos e dinâmica fluvial no Pantanal da Nhecolândia, MS.

No Pantanal da Nhecolândia, lagoas salinas, e os solos Salino-Sódicos a elas associadas, estão sofrendo degradação provavelmente devido ao aporte de águas doces das inundações sazonais. Este trabalho teve como objetivo estudar os solos relacionados a lagoas em degradação, a partir de descrições morfológicas detalhadas e de análises químicas laboratoriais, a fim de estabelecer relações genéticas com os solos Salino-Sódicos das salinas. Observou-se que os solos de duas lagoas em degradação (uma salobra e uma já com água doce) apresentam, em profundidade, horizontes semelhantes ao Btnx presentes nos Solos Salino-Sódicos. Estes horizontes profundos são esverdeados, endurecidos e, geralmente, possuem os maiores valores de pH, porcentagem de sódio trocável (PST) e condutividade elétrica na pasta saturada (CEp), e os menores valores de Al+3+H+ trocáveis do perfil. Estes dados apontam para a ação do processo de solodização nos solos das lagoas salobra e doce, com origem de Solonetz Solodizados ou, ainda, de solos que apresentam resquícios de solo halomórfico, mas não atendem mais aos critérios para serem classificados como tal. A forte lixiviação dos íons devido ao estabelecimento de canais de água doce intermitentes (vazantes) nas áreas das lagoas salinas é a principal responsável pela degradação dos Solos Salino-Sódicos e pelo estabelecimento da solodização

Análise de parâmetros morfológicos, físicos e químicos de solos associados à lagoas de água doce, Pantanal da Nhecolândia.

A sub-região da Nhecolândia do Pantanal Mato-Grossense é composta por lagoas de água doce, situadas em regiões de vazantes e de lagoas salinas localizadas no interior de cordilheiras, havendo predominância de solos halomórficos no entorno das salinas. O objetivo deste trabalho é estudar as características morfológicas e químicas dos solos de uma lagoa de água doce (baías) situada no Pantanal da Nhecolândia, a fim de aumentar o conhecimento sobre os solos associados a este elemento da paisagem. Em campo, os horizontes foram descritos em trincheiras e tradagens e as amostras coletadas foram enviadas para análises de pH; bases trocáveis, Al3+, H++Al3+, CTC (direta) e CE por meio de extrato de pasta saturada. Comparando-se os parâmetros químicos da baía estudada com os de uma lagoa salina próxima, foi possível constatar similaridades tanto morfológicas quanto químicas, o que sugere que, no passado, os solos da baía eram provavelmente do tipo Salino-Sódico como os da salina. Deve ter ocorrido processos de intensa perda de cátions por lixiviação, com a transformação dos solos Salino-Sódicos das salinas em Sódicos ou, majoritariamente, em solos com características não mais halomórficas nas baías

A spectroscopy approach to the study of virus infection in the endophytic fungus Epichloë festucae

<p>Abstract</p> <p>Background</p> <p>In this work we propose a rapid method based on visible and near-infrared (Vis-NIR) spectroscopy to determine the occurrence of double-stranded RNA (dsRNA) viruses in <it>Epichloë festucae </it>strains isolated from <it>Festuca rubra </it>plants. In addition, we examined the incidence of infections by <it>E. festucae </it>in populations of <it>F. rubra </it>collected in natural grasslands of Western Spain.</p> <p>Methods</p> <p>Vis-NIR spectra (400-2498 nm) from 124 virus-infected and virus-free <it>E. festucae </it>isolates were recorded directly from ground and freeze-dried mycelium. To estimate how well the spectra for uninfected and infected fungal samples could be differentiated, we used partial least-squares discriminant analysis (PLS1-DA) and several data pre-treatments to develop calibration models.</p> <p>Results</p> <p>Applying the best regression model, obtained with two sampling years and using standard normal variate (SNV) combined with first derivative transformation to a new validating data set (42 samples), we obtained a correct classification for 75% of the uninfected isolates and up to 86% of the infected isolates.</p> <p>Conclusions</p> <p>The results obtained suggest that Vis-NIR spectroscopy is a promising technology for detection of viral infections in fungal samples when an alternative faster approach is desirable. It provides a tool adequately exact and more time- and cost-saving than the conventional reference analysis.</p

Shark fossil diversity (Squalomorphii, Squatinomorphii, and Galeomorphii) from the Langhian of Brielas (Lower Tagus Basin, Portugal)

The fossiliferous marine Miocene sediments of the Lower Tagus Basin (Portugal) present a great diversity of Chondrichthyes forms. The current study focuses on the fossil sharks from the Langhian Vc unit of the Brielas section, located in the Setúbal Peninsula. A total of 384 isolated fossil teeth were analysed and ascribed to 17 species from the Orders Hexanchiformes, Squaliformes, Squatiniformes, Lamniformes, and Carcharhiniformes. Centrophorus granulosus and Iago angustidens are described for the first time in Portuguese sediments, whereas Pachyscyllium dachiardii and Rhizoprionodon ficheuri represent only their second reported occurrence. Galeorhinus goncalvesi was already known from the Portuguese uppermost Miocene (Alvalade Basin), but it is now recognized in older sediments. Furthermore, the new material seems to include the first reported occurrence of Hexanchus cf. agassizi in Miocene sediments. As a whole, these new findings support the previous palaeoenvironment characterization of a warm infralittoral setting gradually deepening to a circalittoral one, where seasonal upwelling phenomena could have occurred

Long- and short-range correlations and their event-scale dependence in high-multiplicity pp collisions at 1as = 13 TeV

Two-particle angular correlations are measured in high-multiplicity proton-proton collisions at s = 13 TeV by the ALICE Collaboration. The yields of particle pairs at short-( 06\u3b7 3c 0) and long-range (1.6 < | 06\u3b7| < 1.8) in pseudorapidity are extracted on the near-side ( 06\u3c6 3c 0). They are reported as a function of transverse momentum (pT) in the range 1 < pT< 4 GeV/c. Furthermore, the event-scale dependence is studied for the first time by requiring the presence of high-pT leading particles or jets for varying pT thresholds. The results demonstrate that the long-range \u201cridge\u201d yield, possibly related to the collective behavior of the system, is present in events with high-pT processes as well. The magnitudes of the short- and long-range yields are found to grow with the event scale. The results are compared to EPOS LHC and PYTHIA 8 calculations, with and without string-shoving interactions. It is found that while both models describe the qualitative trends in the data, calculations from EPOS LHC show a better quantitative agreement for the pT dependency, while overestimating the event-scale dependency. [Figure not available: see fulltext.