Marlice Botelho Costa

Realization of All-Optical Logic Gates in a Triangular Triple-Core Photonic Crystal Fiber

We propose an all-optical logical gate based in a triple-core photonic fiber crystal operating with two ultrashort fundamental soliton pulses of 100 fs, with pulse amplitude modulation in the modality of amplitude shift keying (PAM-ASK) with binary amplitude modulation. In particular, we examine the performance of a triple-core PCF coupler to execute two-input logical functions. The pulse propagation is modelled by an extended nonlinear Schroedinger equation including the terms associated with the anomalous group-velocity dispersion (GVD) and the third-order dispersion (β3), as well as the nonlinear effects of self-phase modulation (SPM), cross-phase modulation (XPM), self-steepening, and intrapulse Raman scattering (IRS) in a lossless configuration. Our results indicate the possibility of getting logical operations by controlling the phase difference between the input pulses.

Resistência de genótipos de feijoeiro a Bemisia tabaci biótipo B

The study of bean genotypes resistant to the whitefly Bemisia tabaci (Genn.) B biotype (Hemiptera: Aleyrodidae) has been of great importance due to the damage caused by this pest. In this research, bean genotypes were evaluated regarding at- tractiveness to whitefly adults, the preference for oviposition in free-choice and non choice tests, egg-to-adult development time and characterized for the presence, type and number of trichomes. The experiments were carried out under greenhouse conditions initially evaluating 100 bean genotypes. The non-preference type of resistance for feeding and/or antibiosis was observed in the genotypes ARC-3, IAC-Alvorada and Canario 101, and the emergence of adults was strongly influenced by the genotypes. It was also observed a moderate negative correlation between the number of eggs and the number of glandular trichomes, as well as a very strong positive correlation between the number of eggs and the number of unciform non-glandular trichomes.