T-duality of axial and vector dyonic integrable models

A general construction of affine nonabelian (NA)-Toda models in terms of the axial and vector gauged two loop WZNW model is discussed. They represent integrable perturbations of the conformal sigma -models (with tachyons included) describing (charged) black hole type string backgrounds. We study the off-critical T-duality between certain families of axial and vector type integrable models for the case of affine NA-Toda theories with one global U(1) symmetry. In particular we find the Lie algebraic condition defining a subclass of T-selfdual torsionless NA-Toda models and their zero curvature representation. (C) 2001 Academic Press.

Tonometria, paquimetria e comprimento axial ocular em cães glaucomatosos submetidos à ablação uveal intravítrea

Estudaram-se as alterações tonométricas, paquimétricas e de comprimento axial em cães com glaucoma submetidos à ablação uveal intravítrea. Foram avaliados 13 olhos irreversivelmente cegos de cães que apresentavam glaucoma crônico unilateral, nos quais realizou-se a ablação uveal intra-vítrea, por meio de injeção na câmara vítrea de 0,5ml de sulfato de gentamicina (40mg/ml) associado a 0,3ml de fosfato de dexametasona (4mg/ml). As mensurações da pressão intra-ocular (Po), espessura corneana e eixo axial com tonometria de aplanação, paquimetria ultra-sônica e ultra-sonografias modos A e B foram realizadas no dia da ablação (M0) e após uma (M1), quatro (M4), oito (M8), 12 (M12), 24 (M24) e 48 semanas (M48). A Po diminuiu significativamente em todos os momentos em relação ao M0, com aumento da espessura corneana ao longo do experimento. Nas avaliações ultra-sonográficas notou-se diminuição significativa do bulbo ocular a partir de M4, com medidas ultra-sonográficas modo A significativamente maiores que as do modo B. O procedimento foi efetivo na redução da Po e na diminuição do eixo axial, demonstrando ser viável no controle do glaucoma crônico em olhos irreversivelmente cegos, e ser uma alternativa à enucleação e inserção de prótese ocular.

Genetic divergence among Psidium accessions based on biochemical and agronomic variables

Sessenta e nove acessos de Psidium, coletados em seis estados brasileiros, foram analisados para dois métodos não hierárquicos de agrupamento e por componentes principais (CP), visando orientar programas de melhoramento. Foram analisadas as variáveis ácido ascórbico, β-caroteno, licopeno, fenóis totais, flavonóides totais, atividade antioxidante, acidez titulável, sólidos solúveis, açúcares solúveis totais, teor de umidade, diâmetro lateral e transversal do fruto, peso da polpa e das sementes/fruto, número e produção de frutos/planta. Foram observados agrupamentos específicos para os acessos de araçazeiros no método de Tocher e do k-means e na dispersão tridimensional dos quatro CPs. Os acessos de araçazeiros foram separados dos de goiabeira. Não foi observado nenhum agrupamento específico por estado de coleta, indicando a inexistência de barreiras na propagação dos acessos de goiabeira. As análises sugerem a prospecção de maior número de amostras de germoplasma num menor número de regiões, bem como acessos divergentes com alto teor de compostos nutricionais.

Cytogenetic divergence between two sympatric species of Characidium (Teleostei, Characiformes, Crenuchidae) from the Machado River, Minas Gerais, Brazil

Cytogenetic studies were performed on two sympatric species of Characidium, C. gomesi and C. cf. zebra, from the Grande River basin, Minas Gerais State, Brazil. Although both species had a chromosome number of 50 with a karyotype exclusively consisting of meta- and submetacentric chromosomes, interspecific diversity was detected concerning the size of the two first chromosome pairs of the karyotypes. Active nucleolus organizer regions (NORs) were located at the terminal position on the long arm of the 17th pair of C. gomesi and at subterminal position on the long arm of the 23rd pair of C. cf. zebra. For both species the fluorochrome CMA3 stained only the NOR-bearing pair of chromosomes. The heterochromatin pattern also showed some differentiation between these species restricted to the centromeric or pericentromeric region of C. cf. zebra and practically absent in C. gomesi. These data are discussed concerning chromosome diversification in this fish group.

Panoramic evaluation of mesiodistal axial inclinations of maxillary anterior teeth in orthodontically treated subjects

The objectives of this study were to evaluate, through panoramic radiographs, the mesiodistal axial inclinations of the maxillary anterior teeth at the beginning and end of nonextraction orthodontic treatment, and to compare the results with the mesiodistal axial inclinations of a control sample with normal (acceptable) occlusions. Methods: the experimental sample consisted of 40 white patients (20 male, 20 female; mean age, 14 years) with Class I maloccusions who were treated orthodontically with a standard edgewise (not preadjusted) technique without extractions. The mean treatment period was 1.6 years. The control sample comprised 42 white subjects (14 male, 28 female; age range, 12-17 years) with untreated normal (acceptable) occlusions. Panoramic radiographs were taken of the patients at the beginning (T1) and end (T2) of treatment. The mean values of the mesiodistal axial inclination at T1 were compared with the mean values at T2, and both were compared with the mesiodistal axial inclinations of the control sample. Results- the mesiodistal axial inclinations of the maxillary anterior teeth of the experimental group at T1 were different from those of the control group for 50% of the evaluated teeth. In contrast, the inclinations at T2 were consistent with the normal anatomical configuration of the controls. Conclusions: the panoramic radiograph is an effective tool for evaluating the mesiodistal axial inclinations of maxillary anterior teeth.

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.

MAPPING CORRELATION-FUNCTIONS OF SCHWINGER AND AXIAL MODELS

We show that all Green's functions of the Schwinger and axial models can be obtained one from the other. In particular, we show that the two models have the same chiral anomaly. Finally it is demonstrated that the Schwinger model can keep gauge invariance for an arbitrary mass, dispensing with an additional gauge group integration.

Analysis of cement slurries by inductively coupled plasma optical emission spectrometry with axial viewing

The feasibility of Portland cement analysis by introduction of slurries in an inductively coupled plasma optical emission spectrometer (ICP-OES) with axial viewing has been evaluated. After a fast manual grinding of the cement samples, owing to the pulverized state of this material, 0.1% m/v slurries were prepared in 1% v/v HCl. The calibration was performed adopting two strategies: one based on slurries prepared from different masses (50, 75, 100 and 125 mg) of a Portland cement standard reference material (NIST SRM 1881), and the other one based on aqueous reference solutions. A complete analysis of cement for major (Al, Ca, Fe, Mg and Si), minor and trace elements (Mn, P, S, Sr and Ti) was accomplished. Both strategies led to accurate results for commercial Portland cement samples, except for Si and Ti. for which the calibration with aqueous reference solutions resulted in low values. Applying a paired t-test it was shown that most results were in agreement at a 95% confidence level with a conventional fusion decomposition procedure. The ICP-OES with axial viewing and end-on gas configuration for removal of the recombination plasma zone was effective for cement slurry analysis without any undesirable particle deposition in the pre-optics interface and without severe spectral interferences. (C) 2002 Elsevier B.V. B.V. All rights reserved.

Structural behaviour of three-pile caps subjected to axial compressive loading

This work presents a comparative analysis about the behaviour of pile caps supported by 3 piles subjected to axial loading. Piles with 20 cm and 30 cm diameters were analysed. The main reinforcement was maintained in all the specimens, however, the arrangement of the secondary reinforcement varied. The main reinforcement consisted of steel bars connecting the piles. The secondary reinforcement was made up of: (a) bars going through the piles and through the projection of the column, (b) bars forming a network, and (c) vertical and horizontal stirrups. The main objective was the observation of the pile cap behaviour regarding the cracks and the modes of rupture. The real scale specimens were subjected to experimental tests until failure by rupture. Instruments were placed with the aim to obtain the displacement of the bases, the strains in the main and secondary reinforcement bars, in the compression struts, in the lower and upper nodal zones and in the sides of the caps. None of the caps reached failure by rupture with a load less than 1.12 times the theoretical load. The specimens ruptured due to the cracking of the compression strut and/or the yielding of the reinforcement bars in one direction.

Axial-schwinger model

We consider an extension of the axial model where local gauge symmetries are taken into account. The result is a mixing of the axial and Schwinger models. The anomaly of the axial current is calculated by means of the Fujikawa path integral technique and the model is also solved. Besides the well-known features of the particular models (axial and Schwinger) an effective interaction of scalar and gauge fields via a topological current is obtained. This term is responsible for the appearance of massive poles in the propagators that are different from those of both models.

Axial anomaly through analytic regularization

In this work we consider the two-point Green's functions in (1 + 1)-dimensional quantum electrodynamics and show that the correct implementation of analytic regularization gives a gauge invariant result for the vacuum polarization amplitude and the correct coefficient for the axial anomaly.

Double Higgs production and quadratic divergence cancellation in little Higgs models with T-parity

We analyze double Higgs boson production at the Large Hadron Collider in the context of Little Higgs models. In double Higgs production, the diagrams involved are directly related to those that cause the cancellation of the quadratic divergence of the Higgs self-energy, providing a robust prediction for this class of models. We find that in extensions of this model with the inclusion of a so-called T-parity, there is a significant enhancement in the cross sections as compared to the Standard Model. © SISSA 2006.

Genetic divergence in Eucalyptus spp. clones by molecular RAPD markers

The genetic divergence in 20 Eucalyptus spp. clones was evaluated by multivariate techniques based on 167 RAPD markers, of which 155 were polymorphic and 12 monomorphic. The measures of genetic distances were obtained by the arithmetic complement of the coefficients of Jaccard and of Sorenso-Nei and Li and evaluated by the hierarchical methods of Single Linkage clustering and Unweighted Pair Group Method with Arithmetic Mean (UPGMA). Independent of the dissimilarity coefficient, the greatest divergence was found between clones 7 and 17 and the smallest between the clones 11 and 14. Clone clustering was little influenced by the applied procedure so that, adopting the same percentage of divergence, the UPGMA identified two groups less for the coefficient of Sorenso-Nei and Li. The clones evidenced considerable genetic divergence, which is partly associated to the origin of the study material. The clusters formed by the UPGMA clustering algorithm associated to the arithmetic complement of Jaccard were most consistent.

Genetic divergence in sesame based on morphological and agronomic traits

The evaluation of diversity in germplasm collections is important for both plant breeders and germplasm curators to optimize the use of the variability available. Diversity can be estimated by different genetic markers. The purpose of this study was to estimate the genetic divergence of 30 morphological and agronomic traits in 108 sesame genotypes by multivariate analysis. The Cole-Rodgers index was used to establish the dissimilarity matrices. The principal component analysis identified the traits that contributed most to the divergence and the genotypes were clustered by Tocher's optimization. Despite the narrow genetic basis, the markers were efficient to characterize the genotypes and identify the most similar groups or duplicate and divergent genotypes. Greatest variation was found for the traits number of capsules per plant and grain yield.