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151.
Elsa Froufe Duarte V. Gonçalves Amílcar Teixeira Ronaldo Sousa Simone Varandas Mohamed Ghamizi Alexandra Zieritz Manuel Lopes-Lima 《Organisms Diversity & Evolution》2016,16(3):597-611
Many doubts still exist about which freshwater mussel Unio species inhabit Northwest Africa. While some authors refer to the presence of Unio delphinus in the Atlantic North African basins of Morocco, a recent International Union for Conservation of Nature (IUCN) assessment performed on Moroccan Unio species, recognised the existence of a distinct species, Unio foucauldianus, with a critically endangered conservation status. The present study delivered new genetic, morphological, and geographical distribution data on two Unio species (i.e. U. delphinus and U. foucauldianus) greatly increasing the almost non-existent data on these taxa. Bayesian phylogenetic analysis revealed two highly supported geographically concordant clades, which diverged by 3.2?±?0.6 % (uncorrected p distance): the first distributed across Iberia and corresponding to U. delphinus, and the second distributed across Morocco, corresponding to U. foucauldianus. These results were corroborated by the analysis of ten newly developed microsatellite loci as well as shell morphometry. We suggest that the IUCN critically endangered conservation status of U. foucauldianus should be revised and probably down-listed since its actual distribution is much wider than previously described. Phylogenetic relationships with the other Unio species were resolved, showing that U. delphinus and U. foucauldianus fall inside the pictorum lineage. The estimated molecular rate reported herein (0.265?±?0.06 % per million years) represents the first for the Unionida and could be used as a reference in future studies. 相似文献
152.
Gulnar Azevedo e Silva Lenildo de Moura Maria Paula Curado Fabio da Silva Gomes Ubirani Otero Leandro Fórnias Machado de Rezende Regina Paiva Daumas Raphael Mendon?a Guimar?es Karina Cardoso Meira Iuri da Costa Leite Joaquim Gon?alves Valente Ronaldo Ismério Moreira Rosalina Koifman Deborah Carvalho Malta Marcia Sarpa de Campos Mello Thiago Wagnos Guimar?es Guedes Paolo Boffetta 《PloS one》2016,11(2)
Many human cancers develop as a result of exposure to risk factors related to the environment and ways of life. The aim of this study was to estimate attributable fractions of 25 types of cancers resulting from exposure to modifiable risk factors in Brazil. The prevalence of exposure to selected risk factors among adults was obtained from population-based surveys conducted from 2000 to 2008. Risk estimates were based on data drawn from meta-analyses or large, high quality studies. Population-attributable fractions (PAF) for a combination of risk factors, as well as the number of preventable deaths and cancer cases, were calculated for 2020. The known preventable risk factors studied will account for 34% of cancer cases among men and 35% among women in 2020, and for 46% and 39% deaths, respectively. The highest attributable fractions were estimated for tobacco smoking, infections, low consumption of fruits and vegetables, excess weight, reproductive factors, and physical inactivity. This is the first study to systematically estimate the fraction of cancer attributable to potentially modifiable risk factors in Brazil. Strategies for primary prevention of tobacco smoking and control of infection and the promotion of a healthy diet and physical activity should be the main priorities in policies for cancer prevention in the country. 相似文献
153.
Ronaldo S. da Silva Fabiano Corrêa Lucas P. de Oliveira Lisandro J. S. Vieira 《Zeitschrift fur angewandte Ichthyologie》2019,35(2):622-624
We analyzed the length‐weight relation (LWRs) of 14 species of fish, sampled in 30 sandy beaches along the Acre river, encompassing approximately 300 km of the river between the municipalities of Brasileia and Rio Branco, Acre state, Brazil, during the draught period in 2017 (August and September). For sampling, we used a picaré type trawl with 9 m of length, 2 m of height and 5 mm mesh between opposing knots, during the day and night periods. New information was made available for eight fish species. 相似文献
154.
155.
Invasive bivalves may cause great ecological, evolutionary, and economic impacts in freshwater ecosystems. Species such as Corbicula fluminea, Dreissena bugensis, Dreissena polymorpha, Limnoperna fortunei, and Sinanodonta woodiana are widely distributed hyper-successful invaders, but several others not yet invasive (or at least not considered as such) may become so in the near future. These species can affect hydrology, biogeochemical cycling, and biotic interactions through several mechanisms, with impacts ranging from individuals to ecosystems. Freshwater invasive bivalves can create no-analog ecosystems, posing serious difficulties for management, but new techniques are becoming available which may enhance options to detect early introductions and mitigate impacts. Although knowledge about the biology of these bivalves has increased considerably in the last two decades, several fundamental gaps still persist; we suggest new research directions that are worth exploring in the near future. 相似文献
156.
Marco Aurelio M. Freire Jean Faber Nelson Alessandretti M. Lemos Jose Ronaldo Santos Pedro Fran?a Cavalcanti Ramon Hypolito Lima Edgard Morya 《PloS one》2015,10(6)
The development of therapeutic approaches to improve the life quality of people suffering from different types of body paralysis is a current major medical challenge. Brain-machine interface (BMI) can potentially help reestablishing lost sensory and motor functions, allowing patients to use their own brain activity to restore sensorimotor control of paralyzed body parts. Chronic implants of multielectrodes, employed to record neural activity directly from the brain parenchyma, constitute the fundamental component of a BMI. However, before this technique may be effectively available to human clinical trials, it is essential to characterize its long-term impact on the nervous tissue in animal models. In the present study we evaluated how chronic implanted tungsten microelectrode arrays impact the distribution and morphology of interneurons reactive to calcium-binding proteins calbindin (CB), calretinin (CR) and parvalbumin (PV) across the rat’s motor cortex. Our results revealed that chronic microelectrode arrays were well tolerated by the nervous tissue, with recordings remaining viable for up to 6 months after implantation. Furthermore, neither the morphology nor the distribution of inhibitory neurons were broadly impacted. Moreover, restricted microglial activation was observed on the implanted sites. On the whole, our results confirm and expand the notion that tungsten multielectrodes can be deemed as a feasible candidate to future human BMI studies. 相似文献
157.
158.
Ana Paula B. Moreira Gwen Duytschaever Luciane A. Chimetto Tonon Graciela M. Dias Milene Mesquita Margo Cnockaert Ronaldo B. Francini-Filho Paul De Vos Cristiane C. Thompson Fabiano L. Thompson 《Current microbiology》2014,69(4):405-411
Three novel isolates (A-354T, A-328, and A-384) were retrieved from apparently healthy scleractinian Madracis decactis in the remote St Peter & St Paul Archipelago, Mid-Atlantic Ridge, Brazil. The novel isolates formed a distinct lineage based on the phylogenetic reconstruction using the 16S rRNA and pyrH gene sequences. They fell into the Mediterranei clade and their closest phylogenetic neighbour was V. mediterranei species, sharing upto 98.1 % 16S rRNA gene sequence similarity. Genomic analysis including in silico DDH, MLSA, AAI and genomic signature distinguished A-354T from V. mediterranei LMG 19703 (=AK1) with values of 33.3, 94.2, 92 %, and 11.3, respectively. Phenotypically, the novel isolates can be differentiated from V. mediterranei based on the four following features. They do not grow at 8 % NaCl; use d-gluconic acid but not l-galactonic acid lactone as carbon source; and do not have the fatty acid C18:0. Differentiation from both the other Mediterranei clade species (V. maritimus and V. variabilis) is supported by fifteen features. The novel species show lysine decarboxylase and tryptophan deaminase, but not gelatinase and arginine dihydrolase activity; produce acetoin; use α-d-lactose, N-acetyl-d-galactosamine, myo-Inositol, d-gluconic acid, and β-hydroxy-d,l-butyric acid; and present the fatty acids C14:0 iso, C15:0 anteiso, C16:0 iso, C17:0 anteiso, and C17:1x8c . Whole-cell protein profiles, based on MALDI-TOF, showed that the isolates are not clonal and also distinguished them from the closes phylogenetic neighbors. The name Vibrio madracius sp. nov. is proposed to encompass these novel isolates. The G+C content of the type strain A-354T (=LMG 28124T=CBAS 482T) is 44.5 mol%. 相似文献
159.
Nest orientation in social insects has been intensively studied in warmer and cooler climates, particularly in the northern
hemisphere. Previous studies have consistently shown that species subjected to these climatic conditions prefer to select
mostly southern locations where the nests can gain direct sunlight. However, very little is known on nest orientation in tropical
and subtropical social insects. We studied nest orientations initiated by swarms throughout a year in a Brazilian swarm-founding
wasp, Polybia
paulista von Ihering (Hymenoptera: Polistinae). Swarms selected various orientations as nest sites, but there was a particular trend
in that swarms in the winter period (May–August) preferred to build northward-facing nests. This preference is opposite from
that of social wasps observed in the northern hemisphere. Colonies of this species can potentially last for many years with
continuous nesting, but nesting activities of colonies during the winter are severely limited due to cool temperature and
a shortened day length. Northward-facing nests are warmer through the gain of direct solar heat during the winter period;
consequently, choosing northward-facing sites may be advantageous for swarms in terms of a shortened brood development and
shortened time needed to increase metabolic rates during warm-up for flight. 相似文献
160.
Amorim EP Vilarinhos AD Cohen KO Amorim VB Dos Santos-Serejo JA Silva SO Pestana KN Dos Santos VJ Paes NS Monte DC Dos Reis RV 《Genetics and molecular biology》2009,32(1):96-103
The aim of this work was to evaluate the carotenoid content and genetic variability of banana accessions from the Musa germplasm collection held at Embrapa Cassava and Tropical Fruits, Brazil. Forty-two samples were analyzed, including 21 diploids, 19 triploids and two tetraploids. The carotenoid content was analyzed spectrophotometrically and genetic variability was estimated using 653 DArT markers. The average carotenoid content was 4.73 μg.g (-1) , and ranged from 1.06 μg.g (-1) for the triploid Nanica (Cavendish group) to 19.24 μg.g (-1) for the triploid Saney. The diploids Modok Gier and NBA-14 and the triploid Saney had a carotenoid content that was, respectively, 7-fold, 6-fold and 9-fold greater than that of cultivars from the Cavendish group (2.19 μg.g (-1)). The mean similarity among the 42 accessions was 0.63 (range: 0.24 to 1.00). DArT analysis revealed extensive genetic variability in accessions from the Embrapa Musa germplasm bank. 相似文献