A robust contour detection operator with combined push-pull inhibition and surround suppression

Contour detection is a salient operation in many computer vision applications as it extracts features that are important for distinguishing objects in scenes. It is believed to be a primary role of simple cells in visual cortex of the mammalian brain. Many of such cells receive push-pull inhibition or surround suppression. We propose a computational model that exhibits a combination of these two phenomena. It is based on two existing models, which have been proven to be very effective for contour detection. In particular, we introduce a brain-inspired contour operator that combines push-pull and surround inhibition. It turns out that this combination results in a more effective contour detector, which suppresses texture while keeping the strongest responses to lines and edges, when compared to existing models. The proposed model consists of a Combination of Receptive Field (or CORF) model with push-pull inhibition, extended with surround suppression. We demonstrate the effectiveness of the proposed approach on the RuG and Berkeley benchmark data sets of 40 and 500 images, respectively. The proposed push-pull CORF operator with surround suppression outperforms the one without suppression with high statistical significance

Evaluation of reactivation of HSV1, HHV6, CMV and EBV in a population of patients undergoing allogeneic bone marrow transplantation

Herpes viruses are recognized as important pathogens as a result of viral reactivation in immunocompromised hosts, especially in patients undergoing bone marrow transplantation. Objectives of this study were the assessment of the reactivation of herpes virus HSV1, HHV6, CMV and EBV and the correlation between viral reactivation and progression of transplantation in a population of patients undergoing allogeneic bone marrow transplantation at Fondazione IRCCS Ospedale Maggiore Ca’ Granda Policlinico, Milan. Viral DNA was detected and quantified by Real Time PCR in a population of 35 patients undergoing allogeneic bone marrow transplantation. The viral reactivation was observed in 7 patients for HSV1 (20%), 6 patients for HHV6 (17.1%), 11 patients for CMV (31.4%) and 4 patients for EBV (11.4%). Difference in the incidence of aGVDH between patients with viral reactivation versus those for which there was no reactivation was statistically significant. These data confirm the importance of monitoring viral load for the management of antiviral therapy in order to prevent CMV disease and complications related to herpes viruses reactivation