8 research outputs found
Transfer of Visual Learning Between a Virtual and a Real Environment in Honey Bees: The Role of Active Vision
International audienc
Data_Sheet_3_Transfer of Visual Learning Between a Virtual and a Real Environment in Honey Bees: The Role of Active Vision.PDF
<p>To study visual learning in honey bees, we developed a virtual reality (VR) system in which the movements of a tethered bee walking stationary on a spherical treadmill update the visual panorama presented in front of it (closed-loop conditions), thus creating an experience of immersion within a virtual environment. In parallel, we developed a small Y-maze with interchangeable end-boxes, which allowed replacing repeatedly a freely walking bee into the starting point of the maze for repeated decision recording. Using conditioning and transfer experiments between the VR setup and the Y-maze, we studied the extent to which movement freedom and active vision are crucial for learning a simple color discrimination. Approximately 57% of the bees learned the visual discrimination in both conditions. Transfer from VR to the maze improved significantly the beesâ performances: 75% of bees having chosen the CS+ continued doing so and 100% of bees having chosen the CSâ reverted their choice in favor of the CS+. In contrast, no improvement was seen for these two groups of bees during the reciprocal transfer from the Y-maze to VR. In this case, bees exhibited inconsistent choices in the VR setup. The asymmetric transfer between contexts indicates that the information learned in each environment may be different despite the similar learning success. Moreover, it shows that reducing the possibility of active vision and movement freedom in the passage from the maze to the VR impairs the expression of visual learning while increasing them in the reciprocal transfer improves it. Our results underline the active nature of visual processing in bees and allow discussing the developments required for immersive VR experiences in insects.</p
Image_1_Transfer of Visual Learning Between a Virtual and a Real Environment in Honey Bees: The Role of Active Vision.pdf
<p>To study visual learning in honey bees, we developed a virtual reality (VR) system in which the movements of a tethered bee walking stationary on a spherical treadmill update the visual panorama presented in front of it (closed-loop conditions), thus creating an experience of immersion within a virtual environment. In parallel, we developed a small Y-maze with interchangeable end-boxes, which allowed replacing repeatedly a freely walking bee into the starting point of the maze for repeated decision recording. Using conditioning and transfer experiments between the VR setup and the Y-maze, we studied the extent to which movement freedom and active vision are crucial for learning a simple color discrimination. Approximately 57% of the bees learned the visual discrimination in both conditions. Transfer from VR to the maze improved significantly the beesâ performances: 75% of bees having chosen the CS+ continued doing so and 100% of bees having chosen the CSâ reverted their choice in favor of the CS+. In contrast, no improvement was seen for these two groups of bees during the reciprocal transfer from the Y-maze to VR. In this case, bees exhibited inconsistent choices in the VR setup. The asymmetric transfer between contexts indicates that the information learned in each environment may be different despite the similar learning success. Moreover, it shows that reducing the possibility of active vision and movement freedom in the passage from the maze to the VR impairs the expression of visual learning while increasing them in the reciprocal transfer improves it. Our results underline the active nature of visual processing in bees and allow discussing the developments required for immersive VR experiences in insects.</p
Image_2_Transfer of Visual Learning Between a Virtual and a Real Environment in Honey Bees: The Role of Active Vision.pdf
<p>To study visual learning in honey bees, we developed a virtual reality (VR) system in which the movements of a tethered bee walking stationary on a spherical treadmill update the visual panorama presented in front of it (closed-loop conditions), thus creating an experience of immersion within a virtual environment. In parallel, we developed a small Y-maze with interchangeable end-boxes, which allowed replacing repeatedly a freely walking bee into the starting point of the maze for repeated decision recording. Using conditioning and transfer experiments between the VR setup and the Y-maze, we studied the extent to which movement freedom and active vision are crucial for learning a simple color discrimination. Approximately 57% of the bees learned the visual discrimination in both conditions. Transfer from VR to the maze improved significantly the beesâ performances: 75% of bees having chosen the CS+ continued doing so and 100% of bees having chosen the CSâ reverted their choice in favor of the CS+. In contrast, no improvement was seen for these two groups of bees during the reciprocal transfer from the Y-maze to VR. In this case, bees exhibited inconsistent choices in the VR setup. The asymmetric transfer between contexts indicates that the information learned in each environment may be different despite the similar learning success. Moreover, it shows that reducing the possibility of active vision and movement freedom in the passage from the maze to the VR impairs the expression of visual learning while increasing them in the reciprocal transfer improves it. Our results underline the active nature of visual processing in bees and allow discussing the developments required for immersive VR experiences in insects.</p
Data_Sheet_2_Transfer of Visual Learning Between a Virtual and a Real Environment in Honey Bees: The Role of Active Vision.PDF
<p>To study visual learning in honey bees, we developed a virtual reality (VR) system in which the movements of a tethered bee walking stationary on a spherical treadmill update the visual panorama presented in front of it (closed-loop conditions), thus creating an experience of immersion within a virtual environment. In parallel, we developed a small Y-maze with interchangeable end-boxes, which allowed replacing repeatedly a freely walking bee into the starting point of the maze for repeated decision recording. Using conditioning and transfer experiments between the VR setup and the Y-maze, we studied the extent to which movement freedom and active vision are crucial for learning a simple color discrimination. Approximately 57% of the bees learned the visual discrimination in both conditions. Transfer from VR to the maze improved significantly the beesâ performances: 75% of bees having chosen the CS+ continued doing so and 100% of bees having chosen the CSâ reverted their choice in favor of the CS+. In contrast, no improvement was seen for these two groups of bees during the reciprocal transfer from the Y-maze to VR. In this case, bees exhibited inconsistent choices in the VR setup. The asymmetric transfer between contexts indicates that the information learned in each environment may be different despite the similar learning success. Moreover, it shows that reducing the possibility of active vision and movement freedom in the passage from the maze to the VR impairs the expression of visual learning while increasing them in the reciprocal transfer improves it. Our results underline the active nature of visual processing in bees and allow discussing the developments required for immersive VR experiences in insects.</p
Data_Sheet_1_Transfer of Visual Learning Between a Virtual and a Real Environment in Honey Bees: The Role of Active Vision.PDF
<p>To study visual learning in honey bees, we developed a virtual reality (VR) system in which the movements of a tethered bee walking stationary on a spherical treadmill update the visual panorama presented in front of it (closed-loop conditions), thus creating an experience of immersion within a virtual environment. In parallel, we developed a small Y-maze with interchangeable end-boxes, which allowed replacing repeatedly a freely walking bee into the starting point of the maze for repeated decision recording. Using conditioning and transfer experiments between the VR setup and the Y-maze, we studied the extent to which movement freedom and active vision are crucial for learning a simple color discrimination. Approximately 57% of the bees learned the visual discrimination in both conditions. Transfer from VR to the maze improved significantly the beesâ performances: 75% of bees having chosen the CS+ continued doing so and 100% of bees having chosen the CSâ reverted their choice in favor of the CS+. In contrast, no improvement was seen for these two groups of bees during the reciprocal transfer from the Y-maze to VR. In this case, bees exhibited inconsistent choices in the VR setup. The asymmetric transfer between contexts indicates that the information learned in each environment may be different despite the similar learning success. Moreover, it shows that reducing the possibility of active vision and movement freedom in the passage from the maze to the VR impairs the expression of visual learning while increasing them in the reciprocal transfer improves it. Our results underline the active nature of visual processing in bees and allow discussing the developments required for immersive VR experiences in insects.</p
Myocarditis and Pericarditis in Adolescents after First and Second doses of mRNA COVID-19 Vaccines
International audienceNo abstract availabl
Compliance with antibiotic therapy guidelines in french paediatric intensive care units: a multicentre observational study
Abstract Background Bacterial infections (BIs) are widespread in ICUs. The aims of this study were to assess compliance with antibiotic recommendations and factors associated with non-compliance. Methods We conducted an observational study in eight French Paediatric and Neonatal ICUs with an antimicrobial stewardship programme (ASP) organised once a week for the most part. All children receiving antibiotics for a suspected or proven BI were evaluated. Newbornsâ<â72Â h old, neonatesâ<â37 weeks, ageââ„â18 years and children under surgical antimicrobial prophylaxis were excluded. Results 139 suspected (or proven) BI episodes in 134 children were prospectively included during six separate time-periods over one year. The final diagnosis was 26.6% with no BI, 40.3% presumed (i.e., not documented) BI and 35.3% documented BI. Non-compliance with antibiotic recommendations occurred in 51.1%. The main reasons for non-compliance were inappropriate choice of antimicrobials (27.3%), duration of one or more antimicrobials (26.3%) and length of antibiotic therapy (18.0%). In multivariate analyses, the main independent risk factors for non-compliance were prescribingââ„â2 antibiotics (OR 4.06, 95%CI 1.69â9.74, pâ=â0.0017), duration of broad-spectrum antibiotic therapyââ„â4 days (OR 2.59, 95%CI 1.16â5.78, pâ=â0.0199), neurologic compromise at ICU admission (OR 3.41, 95%CI 1.04â11.20, pâ=â0.0431), suspected catheter-related bacteraemia (ORs 3.70 and 5.42, 95%CIs 1.32 to 15.07, pâ<â0.02), a BI site classified as âotherâ (ORs 3.29 and 15.88, 95%CIs 1.16 to 104.76, pâ<â0.03), sepsis with â„â2 organ dysfunctions (OR 4.21, 95%CI 1.42â12.55, pâ=â0.0098), late-onset ventilator-associated pneumonia (OR 6.30, 95%CI 1.15â34.44, pâ=â0.0338) and â„â1 risk factor for extended-spectrum ÎČ-lactamase-producing Enterobacteriaceae (OR 2.56, 95%CI 1.07â6.14, pâ=â0.0353). Main independent factors for compliance were using antibiotic therapy protocols (OR 0.42, 95%CI 0.19â0.92, pâ=â0.0313), respiratory failure at ICU admission (OR 0.36, 95%CI 0.14â0.90, pâ=â0.0281) and aspiration pneumonia (OR 0.37, 95%CI 0.14â0.99, pâ=â0.0486). Conclusions Half of antibiotic prescriptions remain non-compliant with guidelines. Intensivists should reassess on a day-to-day basis the benefit of using several antimicrobials or any broad-spectrum antibiotics and stop antibiotics that are no longer indicated. Developing consensus about treating specific illnesses and using department protocols seem necessary to reduce non-compliance. A daily ASP could also improve compliance in these situations. Trial Registration ClinicalTrials.gov: number NCT04642560. The date of first trial registration was 24/11/2020