339 research outputs found
Avaliação de genótipos de milho doce sob irrigação por aspersão no Baixo Parnaíba.
bitstream/item/72159/1/CPAMN-COM.-TEC.-10-93.pd
Marcadores moleculares para análise genética de germoplasma de pereira: uso na organização dos recursos genéticos e no melhoramento genético.
O objetivo deste estudo foi o de ajustar as metodologias científicas para a obtenção de marcadores microssatélites e RAPD para análise genética do germoplasma conservado em coleções de pera, visando à organização dos recursos genéticos da espécie do Brasil e ao apoio de atividades de melhoramento genético.bitstream/item/73908/1/Circular-Tecnica-93-online.pd
The Chromo-Dielectric Soliton Model: Quark Self Energy and Hadron Bags
The chromo-dielectric soliton model (CDM) is Lorentz- and chirally-invariant.
It has been demonstrated to exhibit dynamical chiral symmetry breaking and
spatial confinement in the locally uniform approximation. We here study the
full nonlocal quark self energy in a color-dielectric medium modeled by a two
parameter Fermi function. Here color confinement is manifest. The self energy
thus obtained is used to calculate quark wave functions in the medium which, in
turn, are used to calculate the nucleon and pion masses in the one gluon
exchange approximation. The nucleon mass is fixed to its empirical value using
scaling arguments; the pion mass (for massless current quarks) turns out to be
small but non-zero, depending on the model parameters.Comment: 24 pages, figures available from the author
Generalized Dynamic Scaling for Critical Magnetic Systems
The short-time behaviour of the critical dynamics for magnetic systems is
investigated with Monte Carlo methods. Without losing the generality, we
consider the relaxation process for the two dimensional Ising and Potts model
starting from an initial state with very high temperature and arbitrary
magnetization. We confirm the generalized scaling form and observe that the
critical characteristic functions of the initial magnetization for the Ising
and the Potts model are quite different.Comment: 32 pages with15 eps-figure
Caracterização preliminar do cacho e da qualidade da uva de onze clones putativos da cultivar "Moscato Branco".
O cacho da cultivar ?Moscato Branco? apresenta compacidade elevada, o que favorece a ocorrência de podridões. Onze clones putativos da cultivar ?Moscato Branco? foram coletados na Serra Gaúcha e estão sendo avaliados para confirmar diferenças em relação à cultivar original
Characterization of Neofabraea actinidiae and N. brasiliensis as causal agents of apple bull's-eye rot in southern Brazil.
The causal agents of apple bull?s-eye rot in southern Brazil have recently been described as Neofabraea actinidiae and N. brasiliensis. Isolates of both species were evaluated for response of mycelial growth index (MGI) to different temperatures, enzyme production, mycelial growth inhibition and effective concentrations (EC 50 and EC 100 ) of the fungicides tri fl umizole, pyrimethanil and thiophanate methyl, as well as aggres- siveness on fruits of "Fuji " hybrid and " Pink Lady " . There was signi ficantly lower mycelium growth in N. brasiliensis compared with N. actinidiae at all temperatures tested. Neither species grew at 3 and 32°C. There were minor differences in production of enzymes in the two species, with all N. brasiliensis isolates showing no production of pectolyase at pH 7. The lowest EC 50 and EC 100 values were observed with thiophanate methyl. In general, " Fuji " fruits were more susceptible to Neofabraea infection and had larger lesions, while N. brasiliensis isolates showed greater aggressiveness on " Fuji " hybrid and " Pink lady " fruits compared with N. actinidiae
Optimal number of pigments in photosynthetic complexes
We study excitation energy transfer in a simple model of photosynthetic
complex. The model, described by Lindblad equation, consists of pigments
interacting via dipole-dipole interaction. Overlapping of pigments induces an
on-site energy disorder, providing a mechanism for blocking the excitation
transfer. Based on the average efficiency as well as robustness of random
configurations of pigments, we calculate the optimal number of pigments that
should be enclosed in a pigment-protein complex of a given size. The results
suggest that a large fraction of pigment configurations are efficient as well
as robust if the number of pigments is properly chosen. We compare optimal
results of the model to the structure of pigment-protein complexes as found in
nature, finding good agreement.Comment: 20 pages, 7 figures; v2.: new appendix, published versio
Análise do polimorfismo da região ITS do rDNA de Cylindrocarpon spp., agente causal do pé-preto da videira utilizando endonucleases.
o pé-preto da videira é uma doença caracterizada pelo declfnio e morte de plantas, causada pelo fungo Cylindrocarpon spp. A análise morfológica e molecular (marcadores RAPO) de isolados coIetados em videiras com sintomas de pé-preto na Região Sul do Brasil revelou grande variabilidade genética e resultou na identificação da espécie C. desfrucfans como agente causal da doença. Estudos moleculares recentes da região ITS de isolados coletados de diversos pafses e identificados como C. destructans sugerem que estes isolados sejam um complexo de várias espécies.Resumo
Identificação de acessos de pereira por meio de Marcadores Moleculares SSR.
Os marcadores microssatélites são freqüentemente multialélicos e segregam de modo co-dominante, amplificando regiões repetitivas do DNA, por meio de iniciadores específicos. Estas características fazem destes marcadores uma excelente escolha para a solução de problemas de rotina em laboratório, como questões de identificação genética de materiais, como nos casos da cultivar Japonesa e das cultivares William's e Ya-li, suspeitas de terem sido trocadas durante o período de micropropagação.Resumo
Finite Size Scaling and Critical Exponents in Critical Relaxation
We simulate the critical relaxation process of the two-dimensional Ising
model with the initial state both completely disordered or completely ordered.
Results of a new method to measure both the dynamic and static critical
exponents are reported, based on the finite size scaling for the dynamics at
the early time. From the time-dependent Binder cumulant, the dynamical exponent
is extracted independently, while the static exponents and
are obtained from the time evolution of the magnetization and its higher
moments.Comment: 24 pages, LaTeX, 10 figure
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