Influence of vision on short-term sound localization training with non-individualized HRTF

International audiencePrevious studies have demonstrated that it is possible for humans to adapt to new HRTF, non-individualized or altered, in a short time period. While natural adaptation, through sound exposure, takes several weeks [1], some training programs have been employed to accelerate adaptation and improve performance on sound localization in a few days (see [2] for a review). The majority of these training programs are based on audio-visual positional or response feedback learning [3] (participants correct their answer after seeing the target position), or on active learning, for example through audio-proprioceptive manipulations [4] (blindfolded participants actively explore the sphere around them by playing a mini sonified version of hot-and-cold game). While all training programs are based on a bimodal coupling (audio-vision [3] or audio-proprioception [4]), they are rarely based on a trimodal one. Therefore, if vision is not necessary for adaptation [4], and audio-visual training can even be less efficient than other methods [1,2], the role of vision in short-term audio localization training remains unclear, especially when action and proprioception are already involved. Our study compares two versions of active trainings: an audio-proprioceptive one and an audio-visuo-proprioceptive one. We hypothesize that combining all modalities leads to better adaptation inducing better performances and a longer remaining effect.The experiment is developed in virtual reality using a HTC Vive as a head- and hand-tracker. 3D audio spatialization is obtained through Steam Audio’s non-individualized built-in HRTF. When applicable, 3D visual information is displayed directly on the Vive screen. A total of 36 participants, equally distributed in 3 groups (G1 to G3), participate in this between-subject design study.G1 is a control group receiving no training session, while the 2 other groups receive a training session of 12 minutes during 3 consecutive days. All the participants also had to perform 5 sound localization tests (no feedback, hand-pointing techniques, 2 repetitions × 33 positions, frontal space): one before the experiment, one after each training session, and the last one 1 week after the first day in order to evaluate the remaining effect. G2 receives an audio-proprioceptive training as exposed in [4]. Participants have to freely scan the space around them with their hand-held Vive controller to find an animal sound hidden around them. The controller-to-target angular distance is sonified and spatialized at the controller position. No visual information is provided. G3 receives the same task as in G2 but, a visual representation of a sphere is also displayed at the hand position during all training sessions (audio-visuo-proprioceptive situation). We measure the angular error in azimuth and elevation during localization tests. Performances are also analyzed in interaural polar coordinate system to discuss front/back and up/down confusion errors. Data from training sessions are logged (total number of found animals and detailed sequence of hand positions) to evaluate how training and vision influence scanning strategy. The experimental phase is taking place right now (10 participants have completed it for the moment) and extends until the end of April. Complete results will be available for the final version of the paper in June. References [1] Carlile, S., and Blackman, T. Relearning auditory spectral cues for locations inside and outside the visual field. J. Assoc. Res. Otolaryngol. 15, 249–263 (2014)[2] Strelnikov, K., Rosito, M., and Barrone, P. Effect of audiovisual training on monaural spatial hearing in horizontal plane. PLoS ONE 6:e18344 (2011)[3] Mendonça, C. A review on auditory space adaptation to altered head-related cues. Front. Neurosci. 8, 219 (2014)[4] Parseihian, G. & Katz, B.F.G. Rapid head-related transfer function adaptation using a virtual auditory environment. J. Acous. Soc. of America 131, 2948–2957 (2012

a retrospective multicenter study

Funding This study was supported in part by a grant from the French government through the « Programme Investissement d’Avenir» (I-SITE ULNE) managed by the Agence Nationale de la Recherche (coVAPid project). Prof. Ignacio Martin-Loeches has been supported by SFI (Science Foundation Ireland), Grant number 20/COV/0038. The funders of the study had no role in the study design, data collection, analysis or interpretation, writing of the report or deci sion to submit for publication.BACKGROUND: Ventilator-associated pneumonia (VAP) is common in patients with severe SARS-CoV-2 pneumonia. The aim of this ancillary analysis of the coVAPid multicenter observational retrospective study is to assess the relationship between adjuvant corticosteroid use and the incidence of VAP. METHODS: Planned ancillary analysis of a multicenter retrospective European cohort in 36 ICUs. Adult patients receiving invasive mechanical ventilation for more than 48 h for SARS-CoV-2 pneumonia were consecutively included between February and May 2020. VAP diagnosis required strict definition with clinical, radiological and quantitative microbiological confirmation. We assessed the association of VAP with corticosteroid treatment using univariate and multivariate cause-specific Cox's proportional hazard models with adjustment on pre-specified confounders. RESULTS: Among the 545 included patients, 191 (35%) received corticosteroids. The proportional hazard assumption for the effect of corticosteroids on the incidence of VAP could not be accepted, indicating that this effect varied during ICU stay. We found a non-significant lower risk of VAP for corticosteroid-treated patients during the first days in the ICU and an increased risk for longer ICU stay. By modeling the effect of corticosteroids with time-dependent coefficients, the association between corticosteroids and the incidence of VAP was not significant (overall effect p = 0.082), with time-dependent hazard ratios (95% confidence interval) of 0.47 (0.17-1.31) at day 2, 0.95 (0.63-1.42) at day 7, 1.48 (1.01-2.16) at day 14 and 1.94 (1.09-3.46) at day 21. CONCLUSIONS: No significant association was found between adjuvant corticosteroid treatment and the incidence of VAP, although a time-varying effect of corticosteroids was identified along the 28-day follow-up.publishersversionpublishe

The Romantic Socialist Origins of Humanitariamism

“Humanitarian” (humanitaire) came into use in French contemporaneously with the emergence of romantic socialism, and in the context of the rebuilding of post-revolutionary French society and its overseas empire beginning in the 1830s. This article excavates this early idea of humanitarianism, documenting an alternative genealogy for the term and its significance that has been overlooked by scholars of both socialism and humanitarianism. This humanitarianism identified a collective humanity as the source of its own salvation, rather than an external, well-meaning benefactor. Unlike liberal models of advocacy, which invoked individualized actors and recipients of their care, socialists privileged solidarity within their community and rejected the foundational logic of liberal individualism. In tracing this history, this article considers its importance for contemporary debates about humanitarianism’s imperial power dynamics

Ocean acidification and temperature rise: effects on calcification during early development of the cuttlefish Sepia officinalis

This study investigated the effects of seawater pH (i.e., 8.10, 7.85 and 7.60) and temperature (16 and 19 °C) on (a) the abiotic conditions in the fluid surrounding the embryo (viz. the perivitelline fluid), (b) growth, development and (c) cuttlebone calcification of embryonic and juvenile stages of the cephalopod Sepia officinalis. Egg swelling increased in response to acidification or warming, leading to an increase in egg surface while the interactive effects suggested a limited plasticity of the swelling modulation. Embryos experienced elevated pCO2 conditions in the perivitelline fluid (>3-fold higher pCO2 than that of ambient seawater), rendering the medium under-saturated even under ambient conditions. The growth of both embryos and juveniles was unaffected by pH, whereas 45Ca incorporation in cuttlebone increased significantly with decreasing pH at both temperatures. This phenomenon of hypercalcification is limited to only a number of animals but does not guarantee functional performance and calls for better mechanistic understanding of calcification processes

Consistent patterns of common species across tropical tree communities

Trees structure the Earth’s most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1,2,3,4,5,6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth’s 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world’s most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.Publisher PDFPeer reviewe

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

SARS-CoV-2 susceptibility and COVID-19 disease severity are associated with genetic variants affecting gene expression in a variety of tissues

Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component. Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci (eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene), including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)