44 research outputs found
Transiting Exoplanet Studies and Community Targets for JWST's Early Release Science Program
This is a white paper that originated from an open discussion at the Enabling Transiting Exoplanet Science with JWST workshop held November 16 - 18, 2015 at STScI (http://www.stsci.edu/jwst/science/exoplanets). Accepted for publication in PASPThis is the author accepted manuscript. The final version is available from IOP Publishing via the DOI in this record.The James Webb Space Telescope will revolutionize transiting exoplanet atmospheric science due to its capability for continuous, long-duration observations and its larger collecting area, spectral coverage, and spectral resolution compared to existing space-based facilities. However, it is unclear precisely how well JWST will perform and which of its myriad instruments and observing modes will be best suited for transiting exoplanet studies. In this article, we describe a prefatory JWST Early Release Science (ERS) program that focuses on testing specific observing modes to quickly give the community the data and experience it needs to plan more efficient and successful future transiting exoplanet characterization programs. We propose a multi-pronged approach wherein one aspect of the program focuses on observing transits of a single target with all of the recommended observing modes to identify and understand potential systematics, compare transmission spectra at overlapping and neighboring wavelength regions, confirm throughputs, and determine overall performances. In our search for transiting exoplanets that are well suited to achieving these goals, we identify 12 objects (dubbed "community targets") that meet our defined criteria. Currently, the most favorable target is WASP-62b because of its large predicted signal size, relatively bright host star, and location in JWST's continuous viewing zone. Since most of the community targets do not have well-characterized atmospheres, we recommend initiating preparatory observing programs to determine the presence of obscuring clouds/hazes within their atmospheres. Measurable spectroscopic features are needed to establish the optimal resolution and wavelength regions for exoplanet characterization. Other initiatives from our proposed ERS program include testing the instrument brightness limits and performing phase-curve observations.(Abridged)K.B.S. recognizes support from the Sagan Fellowship Program, supported by NASA and administered by the NASA Exoplanet Science Institute (NExScI)
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The transiting exoplanet community early release science program for JWST
The transiting exoplanet community early release science program for JWST
The James Webb Space Telescope (JWST) presents the opportunity to transform
our understanding of planets and the origins of life by revealing the
atmospheric compositions, structures, and dynamics of transiting exoplanets in
unprecedented detail. However, the high-precision, time-series observations
required for such investigations have unique technical challenges, and prior
experience with other facilities indicates that there will be a steep learning
curve when JWST becomes operational. In this paper we describe the science
objectives and detailed plans of the Transiting Exoplanet Community Early
Release Science (ERS) Program, which is a recently approved program for JWST
observations early in Cycle 1. The goal of this project, for which the obtained
data will have no exclusive access period, is to accelerate the acquisition and
diffusion of technical expertise for transiting exoplanet observations with
JWST, while also providing a compelling set of representative datasets that
will enable immediate scientific breakthroughs. The Transiting Exoplanet
Community ERS Program will exercise the time-series modes of all four JWST
instruments that have been identified as the consensus highest priorities,
observe the full suite of transiting planet characterization geometries
(transits, eclipses, and phase curves), and target planets with host stars that
span an illustrative range of brightnesses. The observations in this program
were defined through an inclusive and transparent process that had
participation from JWST instrument experts and international leaders in
transiting exoplanet studies. Community engagement in the project will be
centered on a two-phase Data Challenge that culminates with the delivery of
planetary spectra, time-series instrument performance reports, and open-source
data analysis toolkits in time to inform the agenda for Cycle 2 of the JWST
mission
The unfolded protein response in immunity and inflammation.
The unfolded protein response (UPR) is a highly conserved pathway that allows the cell to manage endoplasmic reticulum (ER) stress that is imposed by the secretory demands associated with environmental forces. In this role, the UPR has increasingly been shown to have crucial functions in immunity and inflammation. In this Review, we discuss the importance of the UPR in the development, differentiation, function and survival of immune cells in meeting the needs of an immune response. In addition, we review current insights into how the UPR is involved in complex chronic inflammatory diseases and, through its role in immune regulation, antitumour responses.This work was supported by the Netherlands Organization for Scientific Research Rubicon grant 825.13.012 (J.G.); US National Institutes of Health (NIH) grants DK044319, DK051362, DK053056 and DK088199, and the Harvard Digestive Diseases Center (HDDC) grant DK034854 (R.S.B.); National Institutes of Health grants DK042394, DK088227, DK103183 and CA128814 (R.J.K.); and European Research Council (ERC) Starting Grant 260961, ERC Consolidator Grant 648889, and the Wellcome Trust Investigator award 106260/Z/14/Z (A.K.).This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nri.2016.6
Role of leucocyte caspase-1 activity in epidural-related maternal fever: a single-centre, observational, mechanistic cohort study
BACKGROUND: Epidural-related maternal fever (ERMF) has been reported in ∼26% of labouring women. The underlying mechanisms remain unclear. We hypothesised that ERMF is promoted by bupivacaine disrupting cytokine production/release from mononuclear leucocytes [mononuclear fraction (MNF)]. We examined whether bupivacaine (i) reduces caspase-1 activity and release of the anti-pyrogenic cytokine interleukin (IL)-1 receptor antagonist (IL-1ra), and (ii) is pro-inflammatory through mitochondrial injury/IL-1β. METHODS: In labouring women, blood samples were obtained before/after epidural analgesia was implemented. Maternal temperature was recorded hourly for the first 4 h of epidural analgesia. Time-matched samples/temperatures were obtained from labouring women without epidural analgesia, pregnant non-labouring, and non-pregnant women. The primary clinical outcome was change in maternal temperature over 4 h after the onset of siting epidural catheter/enrolment. The secondary clinical outcome was development of ERMF (temperature ≥ 38°C). The effect of bupivacaine/saline on apoptosis, caspase-1 activity, intracellular IL-1ra, and plasma IL-1ra/IL-1β ratio was quantified in MNF from labouring women or THP-1 monocytes (using flow cytometry, respirometry, or enzyme-linked immunosorbent assay). RESULTS: Maternal temperature increased by 0.06°C h-1 [95% confidence interval (CI): 0.03-0.09; P=0.003; n=38] after labour epidural placement. ERMF only occurred in women receiving epidural analgesia (five of 38; 13.2%). Bupivacaine did not alter MNF or THP-1 apoptosis compared with saline control, but reduced caspase-1 activity by 11% (95% CI: 5-17; n=10) in MNF from women in established labour. Bupivacaine increased intracellular MNF IL-1ra by 25% (95% CI: 10-41; P<0.001; n=10) compared with saline-control. Epidural analgesia reduced plasma IL-1ra/IL-1β ratio (mean reduction: 14; 95% CI: 7-30; n=30) compared with women without epidural analgesia. CONCLUSIONS: Impaired release of anti-pyrogenic IL-1ra might explain ERMF mechanistically. Immunomodulation by bupivacaine during labour could promote ERMF
Influence of M. tuberculosis lineage variability within a clinical trial for pulmonary tuberculosis.
Recent studies suggest that M. tuberculosis lineage and host genetics interact to impact how active tuberculosis presents clinically. We determined the phylogenetic lineages of M. tuberculosis isolates from participants enrolled in the Tuberculosis Trials Consortium Study 28, conducted in Brazil, Canada, South Africa, Spain, Uganda and the United States, and secondarily explored the relationship between lineage, clinical presentation and response to treatment. Large sequence polymorphisms and single nucleotide polymorphisms were analyzed to determine lineage and sublineage of isolates. Of 306 isolates genotyped, 246 (80.4%) belonged to the Euro-American lineage, with sublineage 724 predominating at African sites (99/192, 51.5%), and the Euro-American strains other than 724 predominating at non-African sites (89/114, 78.1%). Uneven distribution of lineages across regions limited our ability to discern significant associations, nonetheless, in univariate analyses, Euro-American sublineage 724 was associated with more severe disease at baseline, and along with the East Asian lineage was associated with lower bacteriologic conversion after 8 weeks of treatment. Disease presentation and response to drug treatment varied by lineage, but these associations were no longer statistically significant after adjustment for other variables associated with week-8 culture status