Photochemically produced SO2 in the atmosphere of WASP-39b

S.-M.T. is supported by the European Research Council advanced grant EXOCONDENSE (no. 740963; principal investigator: R. T. Pierrehumbert). E.K.H.L. is supported by the SNSF Ambizione Fellowship grant (no. 193448). X.Z. is supported by NASA Exoplanet Research grant 80NSSC22K0236. O.V. acknowledges funding from the ANR project ‘EXACT’ (ANR-21-CE49-0008-01), from the Centre National d’Études Spatiales (CNES) and from the CNRS/INSU Programme National de Planétologie (PNP). L.D. acknowledges support from the European Union H2020-MSCA-ITN-2109 under grant no. 860470 (CHAMELEON) and the KU Leuven IDN/19/028 grant Escher. This work benefited from the 2022 Exoplanet Summer Program at the Other Worlds Laboratory (OWL) at the University of California, Santa Cruz, a programme financed by the Heising-Simons Foundation. T.D. is an LSSTC Catalyst Fellow. J.K. is an Imperial College Research Fellow. B.V.R. is a 51 Pegasi b Fellow. L.W. is an NHFP Sagan Fellow. A.D.F. is an NSF Graduate Research Fellow.Photochemistry is a fundamental process of planetary atmospheres that regulates the atmospheric composition and stability1. However, no unambiguous photochemical products have been detected in exoplanet atmospheres so far. Recent observations from the JWST Transiting Exoplanet Community Early Release Science Program2,3 found a spectral absorption feature at 4.05 μm arising from sulfur dioxide (SO2) in the atmosphere of WASP-39b. WASP-39b is a 1.27-Jupiter-radii, Saturn-mass (0.28 MJ) gas giant exoplanet orbiting a Sun-like star with an equilibrium temperature of around 1,100 K (ref. 4). The most plausible way of generating SO2 in such an atmosphere is through photochemical processes5,6. Here we show that the SO2 distribution computed by a suite of photochemical models robustly explains the 4.05-μm spectral feature identified by JWST transmission observations7 with NIRSpec PRISM (2.7σ)8 and G395H (4.5σ)9. SO2 is produced by successive oxidation of sulfur radicals freed when hydrogen sulfide (H2S) is destroyed. The sensitivity of the SO2 feature to the enrichment of the atmosphere by heavy elements (metallicity) suggests that it can be used as a tracer of atmospheric properties, with WASP-39b exhibiting an inferred metallicity of about 10× solar. We further point out that SO2 also shows observable features at ultraviolet and thermal infrared wavelengths not available from the existing observations.Publisher PDFPeer reviewe

IBD risk loci are enriched in multigenic regulatory modules encompassing putative causative genes.

GWAS have identified >200 risk loci for Inflammatory Bowel Disease (IBD). The majority of disease associations are known to be driven by regulatory variants. To identify the putative causative genes that are perturbed by these variants, we generate a large transcriptome data set (nine disease-relevant cell types) and identify 23,650 cis-eQTL. We show that these are determined by ∼9720 regulatory modules, of which ∼3000 operate in multiple tissues and ∼970 on multiple genes. We identify regulatory modules that drive the disease association for 63 of the 200 risk loci, and show that these are enriched in multigenic modules. Based on these analyses, we resequence 45 of the corresponding 100 candidate genes in 6600 Crohn disease (CD) cases and 5500 controls, and show with burden tests that they include likely causative genes. Our analyses indicate that ≥10-fold larger sample sizes will be required to demonstrate the causality of individual genes using this approach

Testing the flexibility of cognitive control using electrophysiological correlates of stimulus-response compatibility

Testing the Flexibility of Cognitive Control using Electrophysiological Correlates of Stimulus-Response Compatibility At work, at home, and on the road, people are more and more often required to make fast decisions and give immediate responses, making it essential to understand the factors that influence human performance. This work investigated how human beings use cognitive control in increasingly complex tasks, aiming to understand how the brain responds in predictable and unpredictable situations. Scientists have developed several techniques for investigating such cognitive functions, and this work combined behavioural and electrophysiological methods: stimulus-response compatibility and EEG. Stimulus-response compatibility (SRC) concerns the relationship between stimuli (such as a red traffic light) and responses (such as pressing the brake), and especially the ease with which a particular stimulus lends to a particular response. We can manipulate SRC, and thus task complexity, by designing tasks with different combinations of stimuli and responses. The effects of task complexity on the brain can then be detected in EEG (electrophysiological measures recorded from the scalp) during experimental tasks. Event Related Potentials (ERPs) offer a means to investigate the precise timing of interference (with more difficult tasks/SRC) and potential measures of cognitive control. The results of four experiments revealed how cognitive control can reduce or increase interference associated with SRC and task difficulty, depending on response strategies and on how predictable a specific type of interference is. Chapters 2 and 3 compared interference induced by the location of the stimulus or by additional ‘distractor’ stimuli, and performance and ERP results suggested that resolving each type of interference relies on different strategies. Chapters 4 and 5 demonstrate how people can reduce interference using proactive (preparatory) control, but how preparing for the most likely or most difficult task can lead to performance detriments and late correction (reactive control) on the unprepared task. In other words, control strategies seem to play an essential role in determining how quickly and accurately we can respond to changing task demands. However, the final discussion relates the experiments to more recent studies, theories and computational modeling, concluding that multiple strategies could still be accountable to a general control mechanism that is most effective with constant updating

Diagnostic accuracy of the SNAP and Spec canine pancreatic lipase tests for pancreatitis in dogs presenting with clinical signs of acute abdominal disease

Objectives To (i) assess the clinical diagnostic accuracy of SNAP canine pancreatic lipase (cPL) and specific canine pancreatic lipase (Spec cPL) and (ii) assess the agreement of an abnormal test result between SNAP cPL and Spec cPL in dogs presenting with acute abdominal disease. Design Prospective observational cohort study. Setting University teaching hospital emergency center. Animals Thirty-eight client-owned dogs that presented with acute abdominal disease, with a known final diagnosis between March 2009 and April 2010. Dogs were retrospectively assigned into 2 groups, dogs with acute pancreatitis (AP) (Group 1) and dogs without AP (Group 2). Interventions Paired serum samples obtained within 24 hours of presentation were analyzed using the SNAP cPL test and Spec cPL assay. Measurements and Results SNAP cPL clinical sensitivity and specificity was 82% (9/11 dogs of group 1) and 59% (16/27 dogs of group 2), respectively. Spec cPL clinical sensitivity and specificity was 70% (7/10 dogs of group 1) and 77% (20/26 dogs of group 2), respectively. Accuracy of the SNAP and Spec cPL for a clinical diagnosis of pancreatitis was found to be 66% and 75%, respectively. Agreement between a positive SNAP (cPL ≥ 200 μg/L) and a clinical diagnosis pancreatitis resulted in κ = 0.33. Agreement between an increased Spec (cPL ≥ 400 μg/L) and a clinical diagnosis of pancreatitis resulted in a κ = 0.43. The agreement between SNAP and Spec cPL (cPL ≥ 200 μg/L) for the entire cohort resulted in κ = 0.78. Conclusion SNAP cPL and Spec cPL results may provide a "false positive" diagnosis of pancreatitis in up to 40% of dogs presenting with acute abdominal disease. There is good overall agreement between SNAP cPL and Spec cPL; however, there were 4/38 dogs with positive SNAP cPL and "normal" Spec cPL

Proactive and reactive control in S-R compatibility: A brain potential analysis

We investigated how proactive and reactive control facilitates performance in mixed stimulus-response compatibility (SRC) tasks. SRC effects were eliminated in mixed tasks and reversed following incompatible trials. In mixed tasks, early preferential response activation was present in stimulus-locked lateralized readiness potentials (LRPs) but reduced following incompatible trials. In event-related potentials (ERPs), stimulus-locked N2 was enhanced in all mixed trials but was not significantly influenced by the preceding trial. A response-locked fronto-central negative component (N-120), peaking just before the response, was largest for mixed compatible trials preceded by incompatible trials. This N-120 was paired with an enhancement to the peak of the response-locked LRP. Proactive control is involved in selection of an S-R mapping via the indirect route of a dual-route model. Reactive control corrects the S-R mapping, particularly when alternating between S-R mappings