Caracterização molecular de mutantes de bananeira da cv. terra por meio de marcadores ISSR.

A técnica de indução de mutação por irradiação tem sido muito empregada em programas de melhoramento de plantas visando a seleção de mutantes com características agronômicas desejáveis. Os marcadores moleculares são importantes ferramentas para a detecção dos efeitos da radiação gama com precisão, uma vez que, com o advento das técnicas modernas de biologia molecular, surgiram diversos métodos de detecção de polimorfismo genético direto; ou seja, em nível de DNA. O maior interesse na aplicação dos marcadores genéticos no melhoramento vegetal é a perspectiva de estabelecer ligações entre os marcadores e os genes que controlam determinada característica (OLIVEIRA et al., 1996).pdf 159

Caracterização agronômica e molecular de mutantes de bananeira 'Pacovan'.

A indução de mutação por raios gama, juntamente com as técnicas de cultivo in vitro, constitui uma ferramenta para os programas de melhoramento visando à redução do porte em bananeira. Essa técnica de mutação induzida tem como objetivo promover o melhoramento de uma única característica governada por um ou poucos genes, conservando as outras características do fenótipo original. Os ISSRs (Inter Simple Sequence Repeats) são marcadores dominantes e reproduzíveis, com a vantagem de gerar grandes quantidades de bandas, sendo amplamente distribuídos ao longo do genoma de eucariontes (FANG & ROOSE, 1997). O objetivo deste trabalho foi selecionar mutantes putativos com porte reduzido da cultivar Pacovan submetida a irradiação com raios gama e estimar a variabilidade genética mediante a utilização de marcadores moleculares ISSR.pdf 159

Ocorrência de injurias mecânicas durante as operações pós-colheita e sua influência na qualidade de manga Tommy Atkins destinada ao mercado europeu.

O objetivo deste estudo foi reconhecer e caracterizar os principais danos na manga Tommy Atkins, identificar os pontos ou etapas do processo no packing house que favorecem sua ocorrência e avaliar sua influência na qualidade do fruto

GRAVITY: the Calibration Unit

We present in this paper the design and characterisation of a new sub-system of the VLTI 2nd generation instrument GRAVITY: the Calibration Unit. The Calibration Unit provides all functions to test and calibrate the beam combiner instrument: it creates two artificial stars on four beams, and dispose of four delay lines with an internal metrology. It also includes artificial stars for the tip-tilt and pupil guiding systems, as well as four metrology pick-up diodes, for tests and calibration of the corresponding sub-systems. The calibration unit also hosts the reference targets to align GRAVITY to the VLTI, and the safety shutters to avoid the metrology light to propagate in the VLTI-lab. We present the results of the characterisation and validtion of these differrent sub-units.Comment: 12 pages, 11 figures. Proceeding of SPIE 9146 "Optical and Infrared Interferometry IV

Interference Phenomenon for the Faddeevian Regularization of 2D Chiral Fermionic Determinants

The classification of the regularization ambiguity of 2D fermionic determinant in three different classes according to the number of second-class constraints, including the new faddeevian regularization, is examined and extended. We found a new and important result that the faddeevian class, with three second-class constraints, possess a free continuous one parameter family of elements. The criterion of unitarity restricts the parameter to the same range found earlier by Jackiw and Rajaraman for the two-constraints class. We studied the restriction imposed by the interference of right-left modes of the chiral Schwinger model ($\chi QED_{2}$) using Stone's soldering formalism. The interference effects between right and left movers, producing the massive vectorial photon, are shown to constrain the regularization parameter to belong to the four-constraints class which is the only non-ambiguous class with a unique regularization parameter.Comment: 15 pages, Revtex. Final version to be published in Phys. Rev.

The GRAVITY metrology system: modeling a metrology in optical fibers

GRAVITY is the second generation VLT Interferometer (VLTI) instrument for high-precision narrow-angle astrometry and phase-referenced interferometric imaging. The laser metrology system of GRAVITY is at the heart of its astrometric mode, which must measure the distance of 2 stars with a precision of 10 micro-arcseconds. This means the metrology has to measure the optical path difference between the two beam combiners of GRAVITY to a level of 5 nm. The metrology design presents some non-common paths that have consequently to be stable at a level of 1 nm. Otherwise they would impact the performance of GRAVITY. The various tests we made in the past on the prototype give us hints on the components responsible for this error, and on their respective contribution to the total error. It is however difficult to assess their exact origin from only OPD measurements, and therefore, to propose a solution to this problem. In this paper, we present the results of a semi-empirical modeling of the fibered metrology system, relying on theoretical basis, as well as on characterisations of key components. The modeling of the metrology system regarding various effects, e.g., temperature, waveguide heating or mechanical stress, will help us to understand how the metrology behave. The goals of this modeling are to 1) model the test set-ups and reproduce the measurements (as a validation of the modeling), 2) determine the origin of the non-common path errors, and 3) propose modifications to the current metrology design to reach the required 1nm stability.Comment: 20 pages, 19 figures. Proceeding of SPIE 9146 "Optical and Infrared Interferometry IV

New possibilities for the gauging of chiral bosons

We study a new mechanism for the electromagnetic gauging of chiral bosons showing that new possibilities emerge for the interacting theory of chiral scalars. We introduce a chirally coupled gauge field necessary to mod out the degree of freedom that obstructs gauge invariance in a system of two opposite chiral bosons soldering them together.Comment: 11 pages, Latex. Accepted for publication in Physical Review

New remarks on the linear constraint self-dual boson and Wess-Zumino terms

In this work we prove in a precise way that the soldering formalism can be applied to the Srivastava chiral boson (SCB), in contradiction with some results appearing in the literature. We have promoted a canonical transformation that shows directly that the SCB is composed of two Floreanini-Jackiw's particles with the same chirality which spectrum is a vacuum-like one. As another conflictive result we have proved that a Wess-Zumino term used in the literature consists of the scalar field, once again denying the assertion that the WZ term adds a new degree of freedom to the SCB theory in order to modify the physics of the system.Comment: 6 pages, Revtex. Final version to appear in Physical Review

Identificação e análise da expressão de genes relacionados com o mal-do-Panamá em bananeira, por meio de PCR em Tempo Real.

A banana é a fruta mais consumida no mundo. No Brasil é cultivada em todo país, destacando-se como cultura de maior expressão econômica. Dentre as doenças que ocorrem o 'mal-do-Panamá', causado pelo fungo Fusarium oxysporum f.sp. cubense (Foc), altamente destrutivo limitando a produção