Les atteintes cardiaques au cours de la leptospirose

PARIS7-Xavier Bichat (751182101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Blind Spectrum Sensing Using Symmetry Property of Cyclic Autocorrelation Function: From Theory to Practice

International audienceSpectrum sensing has been identi ed as the key step of the cognition cycle and the most important function for the establishment of cognitive radio. In this paper, we propose to implement and test the classical energy detection and a novel blind cyclostationnary feature detector based on the symmetry property of the cyclic autocorrelation function (CAF) on the real USRP/GNU Radio platform. Both detection algorithms are employed to blindly sense spectrum for opportunistic access. This study shows that the blind cyclostationnary feature detector outperforms classical energy detector while guarantying an acceptable complexity compared to the ED simplicity. Moreover, di erent experimental results indicate that the blind sensing detector can achieve high detection probability at a low false alarm probability under real channel conditions and low signal-to-noise ratio (SNR)

Empirical antibiotic therapy modalities for Enterobacteriaceae bloodstream infections in older patients and their impact on mortality: a multicentre retrospective study

International audiencePurpose: Enterobacteriaceae (EB) bloodstream infections (BSI) are frequent and serious in older patients. Physicians are faced with the dilemma of prescribing early appropriate empirical antibiotics to limit the risk of death, and sparing broad-spectrum antibiotic prescription. The aim of the study was to assess the rate of appropriate empirical antibiotics prescription to treat EB BSI in older patients and its impact on survival.Methods: This study conducted in 49 centres enrolled retrospectively up to the 10 last consecutive patients aged 75 years and over and treated for EB BSI. Factors related to in-hospital death were investigated using logistic regression.Results: Among the 487 enrolled patients (mean age 86 ± 5.9 years), 70% had at least one risk factor of being infected by third-generation cephalosporins (3GC)-resistant strain; however, only 13.8% of EB strains were resistant to 3GC. An empirical antimicrobial treatment was initiated for 418 patients (85.8%), and for 86% (n = 360/418) of them, it was considered appropriate. In-hospital mortality was 12.7% (n = 62) and was related to the severity of infection (OR 3.17, CI 95% 1.75-5.75), while a urinary portal of entry was protective (OR 0.34, CI 95% 0.19-0.60). Neither the absence of nor inappropriate empirical antibiotics prescription was associated with increased mortality.Conclusion: While patients enrolled in this study were at risk of being infected by multidrug-resistant bacteria, yet mainly treated with 3GC, empirical antibiotics prescription was appropriate in most cases and did not influence mortality