A broadband thermal emission spectrum of the ultra-hot Jupiter WASP-18b

Close-in giant exoplanets with temperatures greater than 2,000 K (''ultra-hot Jupiters'') have been the subject of extensive efforts to determine their atmospheric properties using thermal emission measurements from the Hubble and Spitzer Space Telescopes. However, previous studies have yielded inconsistent results because the small sizes of the spectral features and the limited information content of the data resulted in high sensitivity to the varying assumptions made in the treatment of instrument systematics and the atmospheric retrieval analysis. Here we present a dayside thermal emission spectrum of the ultra-hot Jupiter WASP-18b obtained with the NIRISS instrument on JWST. The data span 0.85 to 2.85 $\mu$m in wavelength at an average resolving power of 400 and exhibit minimal systematics. The spectrum shows three water emission features (at $>$6$\sigma$ confidence) and evidence for optical opacity, possibly due to H$^-$, TiO, and VO (combined significance of 3.8$\sigma$). Models that fit the data require a thermal inversion, molecular dissociation as predicted by chemical equilibrium, a solar heavy element abundance (''metallicity'', M/H = 1.03$_{-0.51}^{+1.11}$ $\times$ solar), and a carbon-to-oxygen (C/O) ratio less than unity. The data also yield a dayside brightness temperature map, which shows a peak in temperature near the sub-stellar point that decreases steeply and symmetrically with longitude toward the terminators.Comment: JWST ERS bright star observations. Uploaded to inform JWST Cycle 2 proposals. Manuscript under review. 50 pages, 14 figures, 2 table

Early Release Science of the exoplanet WASP-39b with JWST NIRCam

Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining the dominant chemical processes at work and, if in equilibrium, revealing planet formation histories. Transmission spectroscopy provides the necessary means by constraining the abundances of oxygen- and carbon-bearing species; however, this requires broad wavelength coverage, moderate spectral resolution, and high precision that, together, are not achievable with previous observatories. Now that JWST has commenced science operations, we are able to observe exoplanets at previously uncharted wavelengths and spectral resolutions. Here we report time-series observations of the transiting exoplanet WASP-39b using JWST's Near InfraRed Camera (NIRCam). The long-wavelength spectroscopic and short-wavelength photometric light curves span 2.0 - 4.0 $\mu$m, exhibit minimal systematics, and reveal well-defined molecular absorption features in the planet's spectrum. Specifically, we detect gaseous H$_2$O in the atmosphere and place an upper limit on the abundance of CH$_4$. The otherwise prominent CO$_2$ feature at 2.8 $\mu$m is largely masked by H$_2$O. The best-fit chemical equilibrium models favour an atmospheric metallicity of 1-100$\times$ solar (i.e., an enrichment of elements heavier than helium relative to the Sun) and a sub-stellar carbon-to-oxygen (C/O) ratio. The inferred high metallicity and low C/O ratio may indicate significant accretion of solid materials during planet formation or disequilibrium processes in the upper atmosphere.Comment: 35 pages, 13 figures, 3 tables, Nature, accepte

Early Release Science of the Exoplanet WASP-39b with JWST NIRSpec G395H

Measuring the abundances of carbon and oxygen in exoplanet atmospheres is considered a crucial avenue for unlocking the formation and evolution of exoplanetary systems. Access to an exoplanet's chemical inventory requires high-precision observations, often inferred from individual molecular detections with low-resolution space-based and high-resolution ground-based facilities. Here we report the medium-resolution (R$\sim$600) transmission spectrum of an exoplanet atmosphere between 3-5 $\mu$m covering multiple absorption features for the Saturn-mass exoplanet WASP-39b, obtained with JWST NIRSpec G395H. Our observations achieve 1.46x photon precision, providing an average transit depth uncertainty of 221 ppm per spectroscopic bin, and present minimal impacts from systematic effects. We detect significant absorption from CO$_2$ (28.5$\sigma$) and H$_2$O (21.5$\sigma$), and identify SO$_2$ as the source of absorption at 4.1 $\mu$m (4.8$\sigma$). Best-fit atmospheric models range between 3 and 10x solar metallicity, with sub-solar to solar C/O ratios. These results, including the detection of SO$_2$, underscore the importance of characterising the chemistry in exoplanet atmospheres, and showcase NIRSpec G395H as an excellent mode for time series observations over this critical wavelength range.Comment: 44 pages, 11 figures, 3 tables. Resubmitted after revision to Natur

Early Release Science of the exoplanet WASP-39b with JWST NIRISS

Transmission spectroscopy provides insight into the atmospheric properties and consequently the formation history, physics, and chemistry of transiting exoplanets. However, obtaining precise inferences of atmospheric properties from transmission spectra requires simultaneously measuring the strength and shape of multiple spectral absorption features from a wide range of chemical species. This has been challenging given the precision and wavelength coverage of previous observatories. Here, we present the transmission spectrum of the Saturn-mass exoplanet WASP-39b obtained using the SOSS mode of the NIRISS instrument on the JWST. This spectrum spans $0.6 - 2.8 \mu$m in wavelength and reveals multiple water absorption bands, the potassium resonance doublet, as well as signatures of clouds. The precision and broad wavelength coverage of NIRISS-SOSS allows us to break model degeneracies between cloud properties and the atmospheric composition of WASP-39b, favoring a heavy element enhancement ("metallicity") of $\sim 10 - 30 \times$ the solar value, a sub-solar carbon-to-oxygen (C/O) ratio, and a solar-to-super-solar potassium-to-oxygen (K/O) ratio. The observations are best explained by wavelength-dependent, non-gray clouds with inhomogeneous coverage of the planet's terminator.Comment: 48 pages, 12 figures, 2 tables. Under review at Natur

Identification of carbon dioxide in an exoplanet atmosphere

Carbon dioxide (CO2) is a key chemical species that is found in a wide range of planetary atmospheres. In the context of exoplanets, CO2 is an indicator of the metal enrichment (that is, elements heavier than helium, also called ‘metallicity’), and thus the formation processes of the primary atmospheres of hot gas giants. It is also one of the most promising species to detect in the secondary atmospheres of terrestrial exoplanets. Previous photometric measurements of transiting planets with the Spitzer Space Telescope have given hints of the presence of CO2, but have not yielded definitive detections owing to the lack of unambiguous spectroscopic identification. Here we present the detection of CO2 in the atmosphere of the gas giant exoplanet WASP-39b from transmission spectroscopy observations obtained with JWST as part of the Early Release Science programme. The data used in this study span 3.0–5.5 micrometres in wavelength and show a prominent CO2 absorption feature at 4.3 micrometres (26-sigma significance). The overall spectrum is well matched by one-dimensional, ten-times solar metallicity models that assume radiative–convective–thermochemical equilibrium and have moderate cloud opacity. These models predict that the atmosphere should have water, carbon monoxide and hydrogen sulfide in addition to CO2, but little methane. Furthermore, we also tentatively detect a small absorption feature near 4.0 micrometres that is not reproduced by these models

The acute effect of LifeMoves� on blood pressure, heart rate, respiratory rate, and perceived stress

Chronic stress is a prevalent problem; stress management techniques such as yoga and meditation are advocated to reduce the detrimental effects of stress. LifeMoves�, a novel stress management technique, guides the participant through upper body movements choreographed to meditative music. The objective of this study was to quantify the acute effects of LifeMoves� participation on psychological and physiological markers of stress. 27 volunteers completed the study. Participation included three, 20-minute practice sessions of LifeMoves� and chair yoga and three testing sessions. During testing, subjects performed 10 minutes of LifeMoves�, chair yoga, or sitting quietly. Blood pressure, heart rate, and respiratory rate were measured and perceived stress assessed on a VAS prior to and following each testing session. Paired t-tests were conducted to assess the effects of each condition on markers of stress and repeated measures ANOVA to evaluate differences between conditions. Systolic BP, RR, and perceived stress decreased but HR and diastolic BP did not change with treatment. There were no differences in the pre-post changes of any variable among the conditions. This study demonstrates that a brief practice of LifeMoves�, chair yoga, or sitting quietly can acutely lower physiological and psychological measures of stress

Rationale and study design of the MyHEART study: A young adult hypertension self-management randomized controlled trial

Young adults (18-39 year-olds) with hypertension have a higher lifetime risk for cardiovascular disease. However, less than 50% of young adults achieve hypertension control in the United States. Hypertension self-management programs are recommended to improve control, but have been targeted to middle-aged and older populations. Young adults need hypertension self-management programs (i.e., home blood pressure monitoring and lifestyle modifications) tailored to their unique needs to lower blood pressure and reduce the risks and medication burden they may face over a lifetime. To address the unmet need in hypertensive care for young adults, we developed MyHEART (My Hypertension Education And Reaching Target), a multi-component, theoretically-based intervention designed to achieve self-management among young adults with uncontrolled hypertension. MyHEART is a patient-centered program, based upon the Self-Determination Theory, that uses evidence-based health behavior approaches to lower blood pressure. Therefore, the objective of this study is to evaluate MyHEART\u27s impact on changes in systolic and diastolic blood pressure compared to usual care after 6 and 12 months in 310 geographically and racially/ethnically diverse young adults with uncontrolled hypertension. Secondary outcomes include MyHEART\u27s impact on behavioral outcomes at 6 and 12 months, compared to usual clinical care (increased physical activity, decreased sodium intake) and to examine whether MyHEART\u27s effects on self-management behavior are mediated through variables of perceived competence, autonomy, motivation, and activation (mediation outcomes). MyHEART is one of the first multicenter, randomized controlled hypertension trials tailored to young adults with primary care. The design and methodology will maximize the generalizability of this study. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03158051

Chemical Profiling of A‐to‐I RNA Editing Using a Click‐Compatible Phenylacrylamide

Straightforward methods for detecting adenosine-to-inosine (A-to-I) RNA editing are key to a better understanding of its regulation, function, and connection with disease. We address this need by developing a novel reagent, N-(4-ethynylphenyl)acrylamide (EPhAA), and illustrating its ability to selectively label inosine in RNA. EPhAA is synthesized in a single step, reacts rapidly with inosine, and is "click"-compatible, enabling flexible attachment of fluorescent probes at editing sites. We first validate EPhAA reactivity and selectivity for inosine in both ribonucleosides and RNA substrates, and then apply our approach to directly monitor in vitro A-to-I RNA editing activity using recombinant ADAR enzymes. This method improves upon existing inosine chemical-labeling techniques and provides a cost-effective, rapid, and non-radioactive approach for detecting inosine formation in RNA. We envision this method will improve the study of A-to-I editing and enable better characterization of RNA modification patterns in different settings

Effect of a telephone health coaching intervention on hypertension control in young adults: the MyHEART randomized clinical trial

Importance: Uncontrolled hypertension (ie, a 24-hour ambulatory systolic blood pressure of ≥130 mm Hg and diastolic blood pressure of ≥80 mm Hg or clinic systolic blood pressure of ≥140 mm Hg and diastolic blood pressure of ≥90 mm Hg) in young adults is a US public health burden. Objective: To evaluate the effect of a telephone coaching and blood pressure self-monitoring intervention compared with usual care on changes in systolic and diastolic blood pressures and behaviors at 6 and 12 months. Design, setting, and participants: This randomized clinical trial included male and female participants aged 18 to 39 years with uncontrolled hypertension confirmed by 24-hour ambulatory blood pressure testing. This was a geographically diverse, multicentered study within 2 large, Midwestern health care systems. Data were collected from October 2017 to February 2022 and analyzed from February to June 2022. Interventions: The My Hypertension Education and Reaching Target (MyHEART) intervention consisted of telephone coaching every 2 weeks for 6 months, with home blood pressure monitoring. Control participants received routine hypertension care. Main outcomes and measures: The co-primary clinical outcomes were changes in 24-hour ambulatory and clinic systolic and diastolic blood pressure at 6 and 12 months. The secondary outcomes were hypertension control (defined as ambulatory systolic blood pressure \u3c130 mm Hg and diastolic blood pressure \u3c80 mm Hg or clinic systolic blood pressure \u3c140 mm Hg and diastolic blood pressure \u3c90 mm Hg) and changes in hypertension self-management behavior. Results: A total of 316 participants were randomized (159 to the control group and 157 to the intervention group) from October 2017 to December 2020. The median (IQR) age was 35 (31-37) years, 145 of 311 participants (46.6%) were female, and 166 (53.4%) were male; 72 (22.8%) were Black, and 222 (70.3%) were White. There were no differences in baseline characteristics between groups. There was no significant difference between control and intervention groups for mean 24-hour ambulatory systolic or diastolic blood pressure or clinic systolic or diastolic blood pressure at 6 or 12 months. However, there was appreciable clinical reduction in blood pressures in both study groups (eg, mean [SD] change in systolic blood pressure in intervention group at 6 months, -4.19 [9.77] mm Hg; P \u3c .001). Hypertension control did not differ between study groups. Participants in the intervention group demonstrated a significant increase in home blood pressure monitoring at 6 and 12 months (eg, 13 of 152 participants [8.6%] checked blood pressure at home at least once a week at baseline vs 30 of 86 [34.9%] at 12 months; P \u3c .001). There was a significant increase in physical activity, defined as active by the Godin-Shephard Leisure-Time Physical Activity Questionnaire, in the intervention group at 6 months (69 of 100 [69.0%] vs 51 of 104 [49.0%]; P = .004) but not at 12 months (49 of 86 [57.0%] vs 49 of 90 [54.4%]; P = .76). There was a significant reduction in mean (SD) sodium intake among intervention participants at 6 months (3968.20 [1725.17] mg vs 3354.72 [1365.75] mg; P = .003) but not 12 months. There were no significant differences in other dietary measures. Conclusions and relevance: The MyHEART intervention did not demonstrate a significant change in systolic or diastolic blood pressures at 6 or 12 months between study groups; however, both study groups had an appreciable reduction in blood pressure. Intervention participants had a significant reduction in dietary sodium intake, increased physical activity, and increased home blood pressure monitoring compared with control participants. These findings suggest that the MyHEART intervention could support behavioral changes in young adults with uncontrolled hypertension. Trial registration: ClinicalTrials.gov Identifier: NCT03158051 . OBJECTIVE: To evaluate the effect of a telephone coaching and blood pressure self-monitoring intervention compared with usual care on changes in systolic and diastolic blood pressures and behaviors at 6 and 12 months. DESIGN, SETTING, AND PARTICIPANTS: This randomized clinical trial included male and female participants aged 18 to 39 years with uncontrolled hypertension confirmed by 24-hour ambulatory blood pressure testing. This was a geographically diverse, multicentered study within 2 large, Midwestern health care systems. Data were collected from October 2017 to February 2022 and analyzed from February to June 2022. INTERVENTIONS: The My Hypertension Education and Reaching Target (MyHEART) intervention consisted of telephone coaching every 2 weeks for 6 months, with home blood pressure monitoring. Control participants received routine hypertension care. MAIN OUTCOMES AND MEASURES: The co-primary clinical outcomes were changes in 24-hour ambulatory and clinic systolic and diastolic blood pressure at 6 and 12 months. The secondary outcomes were hypertension control (defined as ambulatory systolic blood pressure \u3c130 mm Hg and diastolic blood pressure \u3c80 mm Hg or clinic systolic blood pressure \u3c140 mm Hg and diastolic blood pressure \u3c90 mm Hg) and changes in hypertension self-management behavior. RESULTS: A total of 316 participants were randomized (159 to the control group and 157 to the intervention group) from October 2017 to December 2020. The median (IQR) age was 35 (31-37) years, 145 of 311 participants (46.6%) were female, and 166 (53.4%) were male; 72 (22.8%) were Black, and 222 (70.3%) were White. There were no differences in baseline characteristics between groups. There was no significant difference between control and intervention groups for mean 24-hour ambulatory systolic or diastolic blood pressure or clinic systolic or diastolic blood pressure at 6 or 12 months. However, there was appreciable clinical reduction in blood pressures in both study groups (eg, mean [SD] change in systolic blood pressure in intervention group at 6 months, -4.19 [9.77] mm Hg; P \u3c .001). Hypertension control did not differ between study groups. Participants in the intervention group demonstrated a significant increase in home blood pressure monitoring at 6 and 12 months (eg, 13 of 152 participants [8.6%] checked blood pressure at home at least once a week at baseline vs 30 of 86 [34.9%] at 12 months; P \u3c .001). There was a significant increase in physical activity, defined as active by the Godin-Shephard Leisure-Time Physical Activity Questionnaire, in the intervention group at 6 months (69 of 100 [69.0%] vs 51 of 104 [49.0%]; P = .004) but not at 12 months (49 of 86 [57.0%] vs 49 of 90 [54.4%]; P = .76). There was a significant reduction in mean (SD) sodium intake among intervention participants at 6 months (3968.20 [1725.17] mg vs 3354.72 [1365.75] mg; P = .003) but not 12 months. There were no significant differences in other dietary measures. CONCLUSIONS AND RELEVANCE: The MyHEART intervention did not demonstrate a significant change in systolic or diastolic blood pressures at 6 or 12 months between study groups; however, both study groups had an appreciable reduction in blood pressure. Intervention participants had a significant reduction in dietary sodium intake, increased physical activity, and increased home blood pressure monitoring compared with control participants. These findings suggest that the MyHEART intervention could support behavioral changes in young adults with uncontrolled hypertension. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03158051