383 research outputs found
REPRODUCTION AND HABITAT OF TEN BRAZILIAN FROGS (ANURA)
Basic data on habitat, behavior, and reproduction arelacking for most Neotropical frog species and even highertaxonomic groups (Crump 1974; Haddad and Prado2005), particularly for those restricted to the AtlanticForest. Basic reproductive features are the basis of comparativestudies on evolution of major natural historyfeatures (Harvey and Pagel 1998), such as the interspecific relationship between body size and egg number/size (Salthe and Duellman 1973, Crump 1974, Stearns1992). Here, we present data on habitat, reproductivebehavior and quantitative parameters such as adult sizes,egg numbers/sizes of ten sympatric frogs of an altitudinalAtlantic Forest site in Southeastern Brazil
Status of This Memo
This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2006). A mobile node needs at least the following information: a home address, a home agent address, and a security association with home agent to register with the home agent. The process of obtaining this information is called bootstrapping. This document discusses issues involved with how the mobile node can be bootstrapped for Mobile IPv6 (MIPv6) and various potential deployment scenarios for mobile node bootstrapping
ITS-rDNA phylogeny of Colletotrichum spp. causal agent of apple glomerella leaf spot.
Several diseases have affected apple production, among them there is Glomerella leaf spot (GLS) caused by Colletotrichum spp. The first report of this disease in apple was in plants nearby citrus orchards in São Paulo State, Brazil. The origin of this disease is still not clear, and studies based on the molecular phylogeny could relate the organisms evolutionarily and characterize possible mechanisms of divergent evolution. The amplification of 5.8S-ITS (Internal Transcribed Spacer) of rDNA of 51 pathogenic Colletotrichum spp. isolates from apples, pineapple guava and citrus produced one fragment of approximately 600 bases pairs (bp) for all the isolates analyzed. The amplified fragments were cleaved with restriction enzymes, and fragments from 90 to 500bp were obtained. The sequencing of this region allowed the generation of a phylogenetic tree, regardless of their hosts, and 5 isolated groups were obtained. From the "in silico" comparison, it was possible to verify a variation from 93 to 100% of similarity between the sequences studied and the Genbank data base. The causal agent of GLS is nearly related (clustered) to isolates of pineapple guava and to the citrus isolates used as control
Reproductive behavior of Cycloramphus dubius Miranda-Ribeiro (Amphibia, Anura, Leptodactylidae)
Cycloramphus dubius Miranda-Ribeiro. 1920 is a frog species from the coastal Atlantic Forest in Southeastern Brazil. It uses waterfalls of forested rivulets as breeding sites. The eggs are placed outside of water, between rock crevices or roots constantly wetted by water dripping. Clutches have about 60 eggs, and the tadpoles grow attached to rocks, out of water. Males of this species exhibit parental care, biting and/or pushing away strange objects approaching the egg masses. Two types of calls were identified in the spectrograms. The advertisement calls consist of juxtaposed pulses lasting 200ms; the aggressive calls, also have the short pulses structure, and last around 300ms. The aggressive calls are emitted during territorial invasion.233237Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Scinax cruentommus (Anura: Hylidae) in the upper Rio Negro drainage, Amazonas state, Brazil, with the redescription of its advertisement call
Scinax cruentommus (Anura: Hylidae) na bacia do alto Rio Negro, Amazonas, Brasil, com a redescrição do seu canto de anúncio. Nós apresentamos o primeiro registro de Scinax cruentommus no alto Rio Negro, Amazonas, Brasil. Nós também redescrevemos o seu canto de anúncio e fazemos comparações acústicas com os dados disponÃveis para outras espécies do Clado de Scinax ruber da bacia amazônica. Com a obtenção de novos dados para S. cruentommus, os parâmetros acústicos suplementaram a sua diagnose congenérica em relação à s outras espécies amazônicas do Clado de S. ruber além das caracterÃsticas propostas em sua descrição original.Scinax cruentommus (Anura: Hylidae) in the upper Rio Negro drainage, Amazonas state, Brazil, with the redescription of its advertisement call. We provide the first record for Scinax cruentommus from the upper Rio Negro, Amazonas state, Brazil. We also redescribe its advertisement call and make acoustic comparisons with available data for other species of the Scinax ruber Clade in the Amazon Basin. With the assessment of further data on S. cruentommus, the acoustic traits have supplemented its congeneric diagnosis in comparison with the other Amazonian species of the S. ruber Clade besides the features proposed in its original description
Physico-chemical analysis of Albian (Lower Cretaceous) amber from San Just (Spain) : implications for palaeoenvironmental and palaeoecological studies
Amber from a Lower Cretaceous outcrop at San Just, located in the Eastern Iberian Peninsula (Escucha Formation, Maestrat Basin), was investigated to evaluate its physico-chemical properties. Thermogravimetric (TG) and Differential Thermogravimetric (DTG) analyses, infra-red spectroscopy, elemental and C-isotope analyses were performed. Physico-chemical differences between the internal light nuclei and the peripheral darker portions of San Just amber can be attributed to processes of diagenetic alteration that preferentially took place in the external amber border colonized by microorganisms (fungi or bacteria) when the resin was still liquid or slightly polymerized. δ13Camber values of different pieces of the same sample, from the nucleus to the external part, are remarkably homogeneous, as are δ13Camber values of the darker peripheral portions and lighter inner parts of the same samples. Hence, neither invasive microorganisms, nor diagenetic alteration changed the bulk isotopic composition of the amber. δ13C values of different amber samples range from -21.1‰ to -24‰, as expected for C3 plant-derived material. C-isotope analysis, coupled to palaeobotanical, TG and DTG data and infra-red spectra, suggests that San Just amber was exuded by only one conifer species, belonging to either the Cheirolepidiaceae or Aracauriaceae, coniferous families probably living under stable palaeoenvironmental and palaeoecological conditions
Hot-spot consensus of fluoroquinolone-mediated DNA cleavage by Gram-negative and Gram-positive type II DNA topoisomerases
Bacterial DNA gyrase and topoisomerase IV are selective targets of fluoroquinolones. Topoisomerase IV versus gyrase and Gram-positive versus Gram-negative behavior was studied based on the different recognition of DNA sequences by topoisomerase–quinolone complexes. A careful statistical analysis of preferred bases was performed on a large number (>400) of cleavage sites. We found discrete preferred sequences that were similar when using different enzymes (i.e. gyrase and topoisomerase IV) from the same bacterial source, but in part diverse when employing enzymes from different origins (i.e. Escherichia coli and Streptococcus pneumoniae). Subsequent analysis on the wild-type and mutated consensus sequences showed that: (i) Gn/Cn-rich sequences at and around the cleavage site are hot spots for quinolone-mediated strand breaks, especially for E. coli topoisomerases: we elucidated positions required for quinolone and enzyme recognition; (ii) for S. pneumoniae enzymes only, A and T at positions −2 and +6 are discriminating cleavage determinants; (iii) symmetry of the target sequence is a key trait to promote cleavage and (iv) the consensus sequence adopts a heteronomous A/B conformation, which may trigger DNA processing by the enzyme–drug complex
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