Multimode Hong-Ou-mandel interference.

We consider multimode two-photon interference at a beam splitter by photons created by spontaneous parametric down-conversion. The resulting interference pattern is shown to depend upon the transverse spatial symmetry of the pump beam. In an experiment, we employ the first-order Hermite-Gaussian modes in order to show that, by manipulating the pump beam, one can control the resulting two-photon interference behavior. We expect these results to play an important role in the engineering of quantum states of light for use in quantum information processing and quantum imaging.

[Immune response produced by anti-rabies vaccines in marmosets (Callithrix sp)]. / Resposta imune produzida por vacinas anti-rábicas em sagüis (Callithrix sp).

In order to evaluate the immune response produced by rabies vaccines in new world nonhuman primates, thirty marmosets (Callithrix sp) were divided into five groups of six individuals and submitted to five different antirabies vaccination schemes using two distinct commercially available animal vaccines. The first was produced in suckling mouse brain (Fuenzalida and Palacios), and the second in NIL-2 cell culture. Post-vaccine serological monitoring was carried out periodically. The results showed that the Fuenzalida and Palacios vaccine was not able to protect the animals when using a single dose or even with a booster. But when submitted to a vaccination routine similar to that used for humans, the marmosets showed detectable antibodies, and only one succumbed to rabies after being challenged. In addition, the vaccine produced in NIL-2 cell culture induced high antibody levels in all vaccinated animals and all animals survived the viral challenge.