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

Transmission spectroscopy1,2,3 of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations’ relatively narrow wavelength range and spectral resolving power, which precluded the unambiguous identification of other chemical species—in particular the primary carbon-bearing molecules6,7. Here we report a broad-wavelength 0.5–5.5 µm atmospheric transmission spectrum of WASP-39b8, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, measured with the JWST NIRSpec’s PRISM mode9 as part of the JWST Transiting Exoplanet Community Early Release Science Team Program10,11,12. We robustly detect several chemical species at high significance, including Na (19σ), H2O (33σ), CO2 (28σ) and CO (7σ). The non-detection of CH4, combined with a strong CO2 feature, favours atmospheric models with a super-solar atmospheric metallicity. An unanticipated absorption feature at 4 µm is best explained by SO2 (2.7σ), which could be a tracer of atmospheric photochemistry. These observations demonstrate JWST’s sensitivity to a rich diversity of exoplanet compositions and chemical processes

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

The Saturn-mass exoplanet WASP-39b has been the subject of extensive efforts to determine its atmospheric properties using transmission spectroscopy1,2,3,4. However, these efforts have been hampered by modelling degeneracies between composition and cloud properties that are caused by limited data quality5,6,7,8,9. Here we present the transmission spectrum of WASP-39b obtained using the Single-Object Slitless Spectroscopy (SOSS) mode of the Near Infrared Imager and Slitless Spectrograph (NIRISS) instrument on the JWST. This spectrum spans 0.6–2.8 μm in wavelength and shows several water-absorption bands, the potassium resonance doublet and 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, favouring a heavy-element enhancement (‘metallicity’) of about 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 also best explained by wavelength-dependent, non-grey clouds with inhomogeneous coverageof the planet’s terminator

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 (for example, refs. 1,2) 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, which, 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 micrometres, exhibit minimal systematics and reveal well defined molecular absorption features in the planet’s spectrum. Specifically, we detect gaseous water in the atmosphere and place an upper limit on the abundance of methane. The otherwise prominent carbon dioxide feature at 2.8 micrometres is largely masked by water. The best-fit chemical equilibrium models favour an atmospheric metallicity of 1–100-times solar (that is, an enrichment of elements heavier than helium relative to the Sun) and a substellar C/O ratio. The inferred high metallicity and low C/O ratio may indicate significant accretion of solid materials during planet formation (for example, refs. 3,4,) or disequilibrium processes in the upper atmosphere (for example, refs. 5,6)

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 systems1,2. Access to the chemical inventory of an exoplanet requires high-precision observations, often inferred from individual molecular detections with low-resolution space-based3,4,5 and high-resolution ground-based6,7,8 facilities. Here we report the medium-resolution (R ≈ 600) transmission spectrum of an exoplanet atmosphere between 3 and 5 μm covering several absorption features for the Saturn-mass exoplanet WASP-39b (ref. 9), obtained with the Near Infrared Spectrograph (NIRSpec) G395H grating of JWST. Our observations achieve 1.46 times 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 CO2 (28.5σ) and H2O (21.5σ), and identify SO2 as the source of absorption at 4.1 μm (4.8σ). Best-fit atmospheric models range between 3 and 10 times solar metallicity, with sub-solar to solar C/O ratios. These results, including the detection of SO2, underscore the importance of characterizing the chemistry in exoplanet atmospheres and showcase NIRSpec G395H as an excellent mode for time-series observations over this critical wavelength rang

Research on Cognitive Domain in Geoscience Learning: Temporal and Spatial Reasoning

The geosciences are characterized by their particular application of and reliance on temporal and spatial reasoning. Geoscientists must be able to apply their knowledge across a variety of scales. The ability to engage with this kind of task represents a great shift in thinking from where most students begin their studies, be that in K-12 or college. In order to understand how people\u27s ability to spatial and temporal reasoning changes over time requires identification of what skills are essential, assessment of those skills, and then exploration of the impacts of different targeted interventions in geoscience contexts. While more is known about how people reason spatially as compared with temporally, there are still significant gaps in our understanding of spatial reasoning in the geosciences. There are opportunities to build on lessons learned from previous investigations of spatial thinking (e.g. the Spatial Intelligence and Learning Center), including how a community can investigate a specific line of reasoning. There is also a need to build on established research from other domains, from anthropology to cognitive science to physics. In this chapter the authors identified and describe three grand challenges to better understand the need for and growth of spatial and temporal reasoning in geoscience education. These include identifying what reasonings or skills are essential to the geosciences (both broadly and within subdisciplines), and the intertwined challenge of how to assess those reasonings and use those results to improve on what students are learning from their geoscience experiences

Brief report: Characteristics of antidepressant use in patients with heart failure

Paul J Mills1, Joel E Dimsdale1, Suzi Hong1, Geoffrey Van Den Brande2, Laura Redwine2, Barry H Greenberg2, Thomas Rutledge11Department of Psychiatry; 2Department of Medicine, University of California San Diego, La Jolla, CA, USABackground: Depression is common in heart failure (HF), but there is little data on the characteristics of antidepressant use in patients with HF.Objective: To survey basic information on antidepressant prescription characteristics, use, effectiveness, and follow-up.Methods: Observational study in two outpatient cardiology clinics of 37 NYHA class I–IV HF patients taking antidepressant medication.Results: Thirty-one percent of prescriptions for antidepressants were obtained from psychiatrists, 58% from primary care physicians, and 8% from cardiologists. The majority of patients (87%) reported regularly taking their antidepressant medication as prescribed, however 48% reported never having had the dosage of their antidepressant medication adjusted. Only 53% of the patients reported that the medication had helped their mood “almost entirely” or “mostly” back to normal since starting their antidepressants, while the remaining patients reported that their mood was only “halfway” or “somewhat” back to normal or that the medication had not helped their depression at all. Among a subset of 10 patients who completed the Beck Depression (BDI) inventory, 6 still had depressed mood (BDI ≥ 10).Conclusion: The findings from this survey study provide insight into the characteristics of antidepressant use in patients with HF and argue for better follow up of HF patients who are prescribed antidepressants.Keywords: heart failure, antidepressant medication, adherence, effectivenes

Agricultural Microcredit and Household Vulnerability in Rural Malawi

textabstractSixteen girls with Turner syndrome (TS) were treated for 4 years with biosynthetic growth hormone (GH). The dosage was 4IU/m2 body surface s.c. per day over the first 3 years. In the 4th year the dosage was increased to 61 U/m2 per day in the 6 girls with a poor height increment and in 1 girl oxandrolone was added. Ethinyl oestradiol was added after the age of 13. Mean (SD) growth velocities were 3.4 (0.9), 7.2 (1.7), 5.3 (1.3), 4.3 (2.0) and 3.6 (1.5) cm/year before and in the 1st, 2nd, 3rd and 4th year of treatment. Skeletal maturation advanced faster than usual in Turner patients especially in the youger children. Although the mean height prediction increased by 5.6 cm and 11 of the 16 girls have now exceeded their predicted height, the height of the 4 girls who stopped GH treatment exceeded the predicted adult height by only 0 to 3.4 cm

Design and Process Development for Smart Phone Medication Dosing Support System and Educational Platform in HIV/Aids-TB Programs in Zambia

The widespread adoption of cell phones and other mobile platforms represents an opportunity to extend the benefits of personalized, point-of-care, healthcare applications to providers and patients in the developing world. However, the challenges facing the effective deployment of mobile health care applications are complex, and thus require a scalable, flexible, and configurable approach. A service-oriented-architecture-based conceptual framework is proposed to address the challenges of developing and deploying mobile health care applications. A particular emphasis of the framework is a service-agent-modeling-based composite process-personalization support that is needed to support the diverse and adaptable needs of the users

Phosphonium-based polythiophene conjugated polyelectrolytes with different surfactant counterions: thermal properties, self-assembly and photovoltaic performances

© 2020 Society of Industrial Chemistry Phosphonium-based polythiophene conjugated polyelectrolytes (CPEs) with three different counterions (dodecylsulfate, octylsulfate and perfluorooctane sulfonate) are synthesized to determine how the nature of the counterion affects the thermal properties, the self-assembly in thin films and the performance as the cathode interfacial layer in polymer solar cells (PSCs). The counterion has a significant effect on the thermal properties of the CPEs, affecting both their glass transition and crystalline behaviour. Grazing-incidence wide-angle X-ray scattering studies also indicate that changing the nature of the counterion influences the microstructural organization in thin films (face-on versus edge-on orientation). The affinity of the CPEs with the underlying photoactive layer in PSCs is highly correlated with the counterion species. Finally, in addition to an increase of the power conversion efficiency of ca 15% when using these CPEs as cathode interfacial layers in PSCs, a higher device stability is noted, compared to a reference device with a calcium interlayer. © 2020 Society of Industrial Chemistry