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International audience; OBJECTIVES: To provide an overview of the spectrum, characteristics and outcomes of neurologic manifestations associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: We conducted a single-centre retrospective study during the French coronavirus disease 2019 (COVID-19) epidemic in March-April 2020. All COVID-19 patients with de novo neurologic manifestations were eligible. RESULTS: We included 222 COVID-19 patients with neurologic manifestations from 46 centres in France. Median (interquartile range, IQR) age was 65 (53-72) years and 136 patients (61.3%) were male. COVID-19 was severe or critical in 102 patients (45.2%). The most common neurologic diseases were COVID-19-associated encephalopathy (67/222, 30.2%), acute ischaemic cerebrovascular syndrome (57/222, 25.7%), encephalitis (21/222, 9.5%) and Guillain-Barré syndrome (15/222, 6.8%). Neurologic manifestations appeared after the first COVID-19 symptoms with a median (IQR) delay of 6 (3-8) days in COVID-19-associated encephalopathy, 7 (5-10) days in encephalitis, 12 (7-18) days in acute ischaemic cerebrovascular syndrome and 18 (15-28) days in Guillain-Barré syndrome. Brain imaging was performed in 192 patients (86.5%), including 157 magnetic resonance imaging (70.7%). Among patients with acute ischaemic cerebrovascular syndrome, 13 (22.8%) of 57 had multiterritory ischaemic strokes, with large vessel thrombosis in 16 (28.1%) of 57. Brain magnetic resonance imaging of encephalitis patients showed heterogeneous acute nonvascular lesions in 14 (66.7%) of 21. Cerebrospinal fluid of 97 patients (43.7%) was analysed, with pleocytosis found in 18 patients (18.6%) and a positive SARS-CoV-2 PCR result in two patients with encephalitis. The median (IQR) follow-up was 24 (17-34) days with a high short-term mortality rate (28/222, 12.6%). CONCLUSIONS: Clinical spectrum and outcomes of neurologic manifestations associated with SARS-CoV-2 infection were broad and heterogeneous, suggesting different underlying pathogenic processes.

Several algorithms are currently provided to alleviate effects of range overlaid echoes and velocity aliasing in the radar. In this paper, a novel and simple, yet very effective method based on Barker code is presented to solve the range ambiguity problem in high PRF radars. The novelty of this algorithm is derived from the fact that each transmitted pulse is coded with a different circular shifted version of Barker code of length four. Encoding the transmitted pulses in such a way provides the receiver of the potential to resolve up to four overlaid pulses. The direct consequence of this capability is the augmentation of the unambiguous range up to four times. On the top of that, the traditional goal of using the Barker code namely, enhancing the range resolution of the radar is still maintained. To prove the superiority of our algorithm over the existing algorithms in the literature, we conduct some simulations in the context of weather radars. The results indicate obviously that our algorithm outperforms the SZ phase coding technique. The latter has been considered as the one that yields the best performance among its competitors within the family of phase coding techniques.