The Study of Quantum Interference in Metallic Photonic Crystals Doped with Four-Level Quantum Dots

In this work, the absorption coefficient of a metallic photonic crystal doped with nanoparticles has been obtained using numerical simulation techniques. The effects of quantum interference and the concentration of doped particles on the absorption coefficient of the system have been investigated. The nanoparticles have been considered as semiconductor quantum dots which behave as a four-level quantum system and are driven by a single coherent laser field. The results show that changing the position of the photonic band gap about the resonant energy of the two lower levels directly affects the decay rate, and the system can be switched between transparent and opaque states if the probe laser field is tuned to the resonance frequency. These results provide an application for metallic nanostructures in the fabrication of new optical switches and photonic devices

Inhibition of penetration of canine zonae pellucidae by homologous spermatoza in vitro using monoclonal antibodies raised against porcine zonae

Ten monoclonal antibodies (MAbs) raised against porcine zonae pellucidae (PZP) were checked for their reactivity against zonae of other species. Two (MAbs A<SUB>6</SUB> and C<SUB>10</SUB>) out of six MAbs checked reacted with canine zonae as ascertained by indirect immunofluorescence. One of these cross-reactive MAbs (A<SUB>6</SUB>) inhibited the penetration of canine ZP by canine spermatozoa in an in vitro assay by 62.5% and 22% at 10 μ g/ml and 1 μg/ml, concentration, respectively. Epitopes recognized by MAbs A<SUP>6</SUP> and C<SUB>10</SUB> are present on the 55-kDa glycoprotein of PZP as determined by Western blotting experiments. None of the ten anti-PZP MAbs reacted with zonae of the bonnet monkey, hamster or rabbit. Of the six MAbs checked, none showed cross-reactivity against mouse and cat zonae, and of four checked, none reacted with guinea pig zonae. Only one of the ten showed slight reactivity with human zonae