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Biology subjects

Danion, F.

Publications and source records attributed to Danion, F..

3 recordsLinked to original sources

The influence of virtual visual stimulus amplitude to induce standing postural responses

Upright postural control during movement relies on multisensory integration. Yet, the frequency-specific contribution of vision remains poorly characterized in virtual reality (VR). This study investigated how multi-sine visual stimulation amplitude delivered in VR influences standing postural responses. Fifteen healthy adults stood on a force plate wearing a VR headset. Visuo-postural coupling was assessed through coherence and gain analyses between a multi-sine signal (10 sinusoids, 0.12 to 1 Hz) oscillating a virtual environment in one of four amplitudes (0.5, 1, 2, 4 degrees peak-to-peak) and the anteroposterior whole-body angle. All amplitudes elicited measurable postural responses. Increasing amplitude significantly increased postural oscillation and tended to increase coherence, while gain significantly decreased. These results are consistent with a nonlinear control system. The 2 degrees amplitude elicited the largest gain with significant coherence across all stimulated frequencies, suggesting it is suitable for studying visual contributions to postural control during movement execution.

neuroscience↗

3D-ARM-Gaze: a public dataset of 3D Arm Reaching Movements with Gaze information in virtual reality

3D-ARM-Gaze is a public dataset designed to provide natural arm movements together with visual and gaze information when reaching objects in a wide reachable space from a precisely controlled, comfortably seated posture. Participants were involved in picking and placing objects in various positions and orientations in a virtual environment, whereby a specific procedure maximized the workspace explored while ensuring a consistent seated posture. The dataset regroups more than 2.5 million samples recorded from 20 healthy participants performing 14 000 single pick-and-place movements (700 per participant). While initially designed to explore novel prosthesis control strategies based on natural eye-hand and arm coordination, this dataset will also be useful to researchers interested in core sensorimotor control, humanoid robotics, human-robot interactions, as well as for the development and testing of associated solutions in gaze-guided computer vision.

bioinformatics↗

Evaluation of the performance of SARS-CoV-2 serological tools and their positioning in COVID-19 diagnostic strategies.

Rapid and accurate diagnosis is crucial for successful outbreak containment. During the current coronavirus disease 2019 (COVID-19) public health emergency, the gold standard for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection diagnosis is the detection of viral RNA by reverse transcription (RT)-PCR. Additional diagnostic methods enabling the detection of current or past SARS-CoV-2 infection would be highly beneficial to ensure the timely diagnosis of all infected and recovered patients. Here, we investigated several serological tools, i.e., two immunochromatographic lateral flow assays (LFA-1 (Biosynex COVID-19 BSS) and LFA-2 (COVID-19 Sign IgM/IgG)) and two enzyme-linked immunosorbent assays (ELISAs) detecting IgA (ELISA-1 Euroimmun), IgM (ELISA-2 EDI) and/or IgG (ELISA-1 and ELISA-2) based on well-characterized panels of serum samples from patients and healthcare workers with PCR-confirmed COVID-19 and from SARS-CoV-2-negative patients. A total of 272 serum samples were used, including 62 serum samples from hospitalized patients (panel 1 and panel 3), 143 serum samples from healthcare workers (panel 2) diagnosed with COVID-19 and 67 serum samples from negative controls. Diagnostic performances of each assay were assessed according to days after symptom onset (dso) and the antigenic format used by manufacturers. We found overall sensitivities ranging from 69% to 93% on panels 1 and 2 and specificities ranging from 83% to 98%. The clinical sensitivity varied greatly according to the panel tested and the dso. The assays we tested showed poor mutual agreement. A thorough selection of serological assays for the detection of ongoing or past infections is advisable.

microbiology↗