Lorentz-violating nonminimal coupling contributions in mesonic hydrogen atoms and generation of photon higher-order derivative terms

We have studied the contributions of Lorentz-violating CPT-odd and CPT-even nonminimal couplings to the energy spectrum of the mesonic hydrogen and the higher-order radiative corrections to the effective action of the photon sector of a Lorentz-violating version of the scalar electrodynamics. By considering the complex scalar field describes charged mesons (pion or kaon), the non-relativistic limit of the model allows to attain upper-bounds by analyzing its contribution to the mesonic hydrogen energy. By using the experimental data for the $1S$ strong correction shift and the pure QED transitions $4P \rightarrow 3P$, the best upper-bound for the CPT-odd coupling is $<10^{-12}\text{eV}^{-1}$ and for the CPT-even one is $<10^{-16}\text{eV}^{-2}$. Besides, the CPT-odd radiative correction to the photon action is a dimension-5 operator which looks like a higher-order Carroll-Field-Jackiw term. The CPT-even radiative contribution to the photon effective action is a dimension-6 operator which would be a higher-order derivative version of the minimal CPT-even term of the standard model extension

Coupling vortex dynamics with collective excitations in Bose-Einstein Condensates

Here we analyze the collective excitations as well as the expansion of a trapped Bose-Einstein condensate with a vortex line at its center. To this end, we propose a variational method where the variational parameters have to be carefully chosen in order to produce reliable results. Our variational calculations agree with numerical simulations of the Gross-Pitaevskii equation. The system considered here turns out to exhibit four collective modes of which only three can be observed at a time depending of the trap anisotropy. We also demonstrate that these collective modes can be excited using well established experimental methods such as modulation of the s-wave scattering length

Incidência do Pineapple Mealybug wilt Associated VÍrus, PMWAV no Banco Ativo de Germoplasma de abacaxi in vitro da Embrapa Mandioca e Fruticultura.

O abacaxi (Ananas comosus var. comosus) é uma das frutas tropicais mais apreciadas no mundo. O Brasil, como um dos centros de origem e diversidade genética, tem se preocupado com a conservação de germoplasma desta importante fruteira. O abacaxizeiro por ser de propagação vegetativa, possui a vantagem da multiplicação clonal do material de plantio, entretanto, esta prática favorece a disseminação de doenças como as viroses. O PMWaV (Pineapple mealybug wilt-associated virus) é um vírus que infecta o abacaxi causando a doença denominada popularmente de ?Mucha do abacaxi?. O vírus transmitido pela cochonilha Dysmicoccus brevipes, e atualmente, acredita-se que a doença seja causada por um complexo viral, denominados PMWaV-1, PMWaV-2 e PMWaV-3, que se diferenciam pela sequência e organização do genoma. O PMWV pertence a família Closteroviridae, gênero Ampelovirus, possui partícula alongada flexuosa e genoma de RNA fita simples com aproximadamente 14Kb. Além dos danos diretos na produção da planta, a contaminação dos acessos do Banco Ativo de Germoplasma -BAG é um fator preocupante. Diante disto, o objetivo deste trabalho foi a avaliar a incidência do PMWaV-1,2,3 nos acesso do BAG in vitro da Embrapa Mandioca e Fruticultura.PDF. 094