Karyotypic similarity among Barycholos temetzi and five species of the genus Eleutherodactylus from southeastern Brazil (Anura, Brachycephalidae)

Comparative cytogenetic analyses were carried out in six species of Brachycephalidae from southeastern Brazil. Barycholos ternetzi, Eleutherodactylus binotatus, Eleutherodactylus guentheri, Eleutherodactylus juipoca, Eleutherodactylus parvus and Eleutherodactylus sp. have 2n = 22 karyotypes with a marked variation in the morphology of chromosome pairs 8, 10 and 11, which are of telocentric or metacentric types, resulting in FN = 38, 40 and 44. Eleutherodactylus have a single chromosome pair bearing Ag-NOR, i.e. pair 1 in E. binotatus, pair 6 in E. guentheri and E. parvus, and pair 11 in E. juipoca and Eleutherodactylus sp. In contrast, B. ternetzi showed Ag-positive sites in the chromosome pairs 1, 4, 5, 9 and 11, and only one to three labelings per metdphase in each individual. Nevertheless, the main chromosome pair with Ag-NOR in the species seems to be the 11th, like in E. juipoca and Eleutherodactylus sp. The NOR site was confirmed by fluorescence in situ hybridization (FISH) technique in E. binotatus and in B. ternetzi, bearing 1p1p and 9p11p11p Ag-NOR pattern, respectively. All the species exhibited predominantly centromeric C-banding pattern, but interstitial bands have also been observed in some cases. In E. binotatus, there is an indication of geographical difference in the distribution of the interstitial C-bands. The fluorochromes GC-specific chromomycin A(3) (CMA(3)) and AT-specific 4',6-diamidino-2-phenylindole (DAPI), with distamycin A (DA) counterstaining, provided the molecular content of some repetitive regions in the karyotypes of the species. One male of E. binotatus presented an extensive heteromorphism, involving at least five different pairs, probably as a consequence of multiple reciprocal translocations. Such rearrangements might be responsible for the multivalent chain seen in the meiosis of this specimen, as well as in another male, although not exhibiting chromosome heteromorphism. The remaining males and those belonging to the other species have always shown 11 bivalents in diplotene and metaphase I cells. In all male specimens, metaphases II presented 11 chromosomes. Despite the observed discrepancies, the five species of Eleutherodactylus have a great uniformity in the 2n = 22 karyotypes, suggesting an assemblage of species from southeastern and southern Brazil, in contrast to northern and northeastern assemblage which is characterized by higher diploid numbers. Undoubtedly, B. ternetzi could be included in that proposed assemblage, due to its karyotypic similarity with the Eleutherodactylus species, as evidenced in the present study. This fact strongly supports the close relationships of both genera, previously inferred on the basis of several characters shared by their species. (C) 2006 Elsevier Ltd. All rights reserved.

Karyotypic Data on 28 Species of Scinax (Amphibia: Anura: Hylidae): Diversity and Informative Variation

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparative cytogenetics of eight species of Cycloramphus (Anura, Cycloramphidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cytogenetics of four Omophoita species (Coleoptera, Chrysomelidae, Alticinae): A comparative analysis using mitotic and meiotic cells submitted to the standard staining and C-banding technique

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Chromosome evolution in three Brazilian Leptodactylus species (Anura, Leptodactylidae), with phylogenetic considerations

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Karyotype characterization, constitutive heterochromatin and nucleolus organizer regions of Paranaita opima (Coleoptera, Chrysomelidae, Alticinae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Intrageneric karyotypic divergence in Scythrophrys and new insights into the relationship with Paratelmatobius (Anura, Leptodactylidae)

Three populations of Scythrophrys from Brazil were studied cytogenetically. The karyotype found in Piraquara (Parana State) and Sao Bento do Sul (Santa Catarina State) (karyotype 1) differed from that of Rancho Queimado (Santa Catarina State) (karyotype 11) in NOR location and in the occurrence of some C-bands. In karyotype I, pair 5 contained NOR-bearing chromosomes, while in karyotype 11 the NOR occurred in pair 10. This difference probably accounts for the inverted classification of pairs 5 and 6 in these karyotypes, which appear to be homologous, as suggested by the presence of heterochromatic markers. These karyotypes also differed in the size of the non-centromeric C-bands in pairs 1 and 8. Comparison of the Scythrophrys karyotypes with those of the related genus Paratelmatobius revealed several similarities, especially between karyotype 11 of Scythrophrys and that of P. poecilogaster. Both karyotypes had a NOR in pair 10, so it was inferred to be present also in the common ancestor for these genera. The non-centromeric C-bands in pairs 7, 10, and in pair 5 of karyotype I and pair 6 of karyotype II of Scythrophrys are characters exclusively found in this genus.

Similaridade cariotípica entre Barycholos ternetzi e cinco espécies do gênero Eleutherodactylus do Sudoeste do Brasil (Anura, Leptodactylidae, Eleutherodactylinae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cooper pair dispersion relation in two dimensions

The Cooper pair binding energy vs. center-of-mass-momentum dispersion relation for Bose-Einstein condensation studies of superconductivity is found in two dimensions for a renormalized attractive delta interaction. It crosses over smoothly from a linear to a quadratic form as coupling varies from weak to strong.

Dietary macronutrients, endocrine functioning and intermediary metabolism in broiler chickens - Pair wise substitutions between protein, fat and carbohydrate

Three pens of male broiler chicks were raised under standard conditions and fed from 7 to 42 days of age three isocaloric diets each with 15.8; 19.6 and 19.5% of CP; and 51, 51, and 44% of CHO; and 6.5; 3.0 and 7.7% of fat, and designated as the low protein (LowCP), low lipid (LowL) and low carbohydrate (LowCHO) diets, respectively. Body weights and feed intake were monitored weekly and blood samples were collected at the same time for posterior analysis of hormone and metabolite content. Chickens fed the LowCP diet were characterized by a reduced body weight gain and feed intake and poorer feed conversion efficiency compared to those fed the LowL and LowCHO diets, which were very similar in this respect. Plasma corticosterone and glucose levels and creatine kinase activity were not significantly changed by diet composition. LowCP chickens were characterised by the lowest plasma T-4 and uric acid levels (indicative for reduced protein breakdown and lower protein ingestion) but highest plasma triglyceride levels (congruent with their higher fat deposition) compared to the LowL and LowCHO chickens. LowL chickens had on average higher plasma T-3 and free fatty acid levels compared to the LowCP and LowCHO chickens.In conclusion, a limited substitution of carbohydrate for fat in iso-nitrogenous, iso-energetic diets has no pronounced effects on plasma hormone and metabolite levels, except for the elevation in T-3 (may enhance glucose uptake) and free fatty acid levels in the plasma of the chickens fed the LowL diet. The protein content of the diet has a greater impact on zootechnical performance, and underlying endocrine regulation of the intermediary metabolism compared to the dietary lipid and CHO fraction. (C) 2003 Elsevier B.V. All rights reserved.

Search for resonant pair production of neutral long-lived particles decaying to bb̄ in pp̄ collisions at s=1.96TeV

We report on a first search for resonant pair production of neutral long-lived particles (NLLP) which each decay to a bb̄ pair, using 3.6fb-1 of data recorded with the D0 detector at the Fermilab Tevatron collider. We search for pairs of displaced vertices in the tracking detector at radii in the range 1.6-20cm from the beam axis. No significant excess is observed above background, and upper limits are set on the production rate in a hidden-valley benchmark model for a range of Higgs boson masses and NLLP masses and lifetimes. © 2009 The American Physical Society.

Search for pair production of excited top quarks in the lepton plus jets final state

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for the associated production of the Higgs boson with a top-quark pair

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Measurement of prompt J/psi pair production in pp collisions at root s = 7 Tev

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)