Performance of an adaptive homodyne receiver in the presence of multipath, Rayleigh-fading and time-varying quadrature errors

In this paper, we carry out a detailed performance analysis of the blind source separation based I/Q corrector operating at the baseband. Performance of the digital I/Q corrector is evaluated not only under time-varying phase and gain errors but also in the presence of multipath and Rayleigh fading channels. Performance under low-SNR and different modulation formats and constellation sizes is also evaluated. What is more, BER improvement after correction is illustrated. The results indicate that the adaptive algorithm offers adequate performance for most communication applications hence, reducing the matching requirements of the analog front-end enabling higher levels of integration.

Presence and characterisation of ecotin in F. necrophorum

Fusobacterium necrophorum is a causative agent of Lemierre’s syndrome (LS) in humans. LS is characterised by thrombophlebitis of the jugular vein and bacteraemia. Disseminated intravascular coagulation is also a documented symptom. F. necrophorum is a Gram-negative, anaerobic bacterium known to possess virulence genes such as a haemolysin, filamentous haemagglutinin and leukotoxin, which target host blood components. Ecotin is a serine protease inhibitor that has not previously been characterised in F. necrophorum, but in E.coli has been shown to have a potent anticoagulant effect. Next generation and Sanger sequencing were used to confirm the presence of the ecotin gene in the genomes of a collection of F. necrophorum clinical and reference strains. When translated, it was found to be a highly conserved protein made up of159 amino acids. Enzyme/substrate inhibition assays demonstrated that F. necrophorum ecotin inhibits human plasma kallikrein and human neutrophil elastase in a dose-dependent manner. Data will also be presented on the anticoagulant effects of ecotin during activated partial thromboplastin time, thrombin time and prothrombin time tests on human donor blood. The mechanisms for how this organism reaches the bloodstream and the significance of this serine protease inhibitor during F. necrophorum infections remain to be elucidated