Comparative study of CH+ and SH+ absorption lines observed towards distant star-forming regions

Aims. The HIFI instrument onboard Herschel has allowed high spectral resolution and sensitive observations of ground-state transi- tions of three molecular ions: the methylidyne cation CH+, its isotopologue 13CH+, and sulfanylium SH+. Because of their unique chemical properties, a comparative analysis of these cations provides essential clues to the link between the chemistry and dynamics of the diffuse interstellar medium. Methods. The CH+, 13CH+, and SH+ lines are observed in absorption towards the distant high-mass star-forming regions (SFRs) DR21(OH), G34.3+0.1, W31C, W33A, W49N, and W51, and towards two sources close to the Galactic centre, SgrB2(N) and SgrA*+50. All sight lines sample the diffuse interstellar matter along pathlengths of several kiloparsecs across the Galactic Plane. In order to compare the velocity structure of each species, the observed line profiles were deconvolved from the hyperfine structure of the SH+ transition and the CH+, 13CH+, and SH+ spectra were independently decomposed into Gaussian velocity components. To analyse the chemical composition of the foreground gas, all spectra were divided, in a second step, into velocity intervals over which the CH+, 13CH+, and SH+ column densities and abundances were derived. Results. SH+ is detected along all observed lines of sight, with a velocity structure close to that of CH+ and 13CH+. The linewidth distributions of the CH+, SH+, and 13CH+ Gaussian components are found to be similar. These distributions have the same mean ( ~ 4.2 km s-1) and standard deviation (\sigma(\delta\u{psion}) ~ 1.5 km s-1). This mean value is also close to that of the linewidth distribution of the CH+ visible transitions detected in the solar neighbourhood. We show that the lack of absorption components narrower than 2 km s-1 is not an artefact caused by noise: the CH+, 13CH+, and SH+ line profiles are therefore statistically broader than those of most species detected in absorption in diffuse interstellar gas (e. g. HCO+, CH, or CN). The SH+/CH+ column density ratio observed in the components located away from the Galactic centre spans two orders of magnitude and correlates with the CH+ abundance. Conversely, the ratio observed in the components close to the Galactic centre varies over less than one order of magnitude with no apparent correlation with the CH+ abundance. The observed dynamical and chemical properties of SH+ and CH+ are proposed to trace the ubiquitous process of turbulent dissipation, in shocks or shears, in the diffuse ISM and the specific environment of the Galactic centre regions

Neoadjuvant Osimertinib for the Treatment of Stage I-IIIA Epidermal Growth Factor Receptor–Mutated Non–Small Cell Lung Cancer: A Phase II Multicenter Study

PurposeTo assess the safety and efficacy of the third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor osimertinib as neoadjuvant therapy in patients with surgically resectable stage I-IIIA EGFR-mutated non-small cell lung cancer (NSCLC).Patients and methodsThis was a multi-institutional phase II trial of neoadjuvant osimertinib for patients with surgically resectable stage I-IIIA (American Joint Committee on Cancer [AJCC] V7) EGFR-mutated (L858R or exon 19 deletion) NSCLC (ClinicalTrials.gov identifier: NCT03433469). Patients received osimertinib 80 mg orally once daily for up to two 28-day cycles before surgical resection. The primary end point was major pathological response (MPR) rate. Secondary safety and efficacy end points were also assessed. Exploratory end points included pretreatment and post-treatment tumor mutation profiling.ResultsA total of 27 patients were enrolled and treated with neoadjuvant osimertinib for a median 56 days before surgical resection. Twenty-four (89%) patients underwent subsequent surgery; three (11%) patients were converted to definitive chemoradiotherapy. The MPR rate was 14.8% (95% CI, 4.2 to 33.7). No pathological complete responses were observed. The ORR was 52%, and the median DFS was 40.9 months. One treatment-related serious adverse event (AE) occurred (3.7%). No patients were unable to undergo surgical resection or had surgery delayed because of an AE. The most common co-occurring tumor genomic alterations were in TP53 (42%) and RBM10 (21%).ConclusionTreatment with neoadjuvant osimertinib in surgically resectable (stage IA-IIIA, AJCC V7) EGFR-mutated NSCLC did not meet its primary end point for MPR rate. However, neoadjuvant osimertinib did not lead to unanticipated AEs, surgical delays, nor result in a significant unresectability rate

The UKIRT Hemisphere Survey: Definition and Full J-band Data Release

This paper defines the UK Infra-red Telescope (UKIRT) Hemisphere Survey (UHS) and release of the complete J-band dataset. The UHS provides continuous coverage in the northern hemisphere from a declination of 0 deg to 60 deg by combining the existing Large Area Survey, Galactic Plane Survey and Galactic Clusters Survey conducted under the UKIRT Infra-red Deep Sky Survey (UKIDSS) programme with a new additional ~12,700 sq.deg area not covered by UKIDSS. This data release includes J-band imaging and source catalogues over the new area, which, together with UKIDSS, completes the J-band UHS coverage over the full ~17,900 sq.deg area. 98 per cent of the data in this release have passed quality control criteria, the remaining 2 per cent being scheduled for re-observation. The median 5-sigma point source sensitivity of the released data is 19.6 mag (Vega). The median full width at half-maximum of the point spread function across the dataset is 0.75 arcsec. In this paper, we outline the survey management, data acquisition, processing and calibration, quality control and archiving as well as summarising the characteristics of the released data products. The data are initially available to a limited consortium with a world-wide release scheduled for August 2018

A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope

Globular clusters with their large populations of millisecond pulsars (MSPs) are believed to be potential emitters of high-energy gamma-ray emission. Our goal is to constrain the millisecond pulsar populations in globular clusters from analysis of gamma-ray observations. We use 546 days of continuous sky-survey observations obtained with the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope to study the gamma-ray emission towards 13 globular clusters. Steady point-like high-energy gamma-ray emission has been significantly detected towards 8 globular clusters. Five of them (47 Tucanae, Omega Cen, NGC 6388, Terzan 5, and M 28) show hard spectral power indices $(0.7 < \Gamma <1.4)$ and clear evidence for an exponential cut-off in the range 1.0-2.6 GeV, which is the characteristic signature of magnetospheric emission from MSPs. Three of them (M 62, NGC 6440 and NGC 6652) also show hard spectral indices $(1.0 < \Gamma < 1.7)$, however the presence of an exponential cut-off can not be unambiguously established. Three of them (Omega Cen, NGC 6388, NGC 6652) have no known radio or X-ray MSPs yet still exhibit MSP spectral properties. From the observed gamma-ray luminosities, we estimate the total number of MSPs that is expected to be present in these globular clusters. We show that our estimates of the MSP population correlate with the stellar encounter rate and we estimate 2600-4700 MSPs in Galactic globular clusters, commensurate with previous estimates. The observation of high-energy gamma-ray emission from a globular cluster thus provides a reliable independent method to assess their millisecond pulsar populations that can be used to make constraints on the original neutron star X-ray binary population, essential for understanding the importance of binary systems in slowing the inevitable core collapse of globular clusters.Comment: Accepted for publication in A&A. Corresponding authors: J. Kn\"odlseder, N. Webb, B. Pancraz

Framing the concept of satellite remote sensing essential biodiversity variables: challenges and future directions

Although satellite-based variables have for long been expected to be key components to a unified and global biodiversity monitoring strategy, a definitive and agreed list of these variables still remains elusive. The growth of interest in biodiversity variables observable from space has been partly underpinned by the development of the essential biodiversity variable (EBV) framework by the Group on Earth Observations – Biodiversity Observation Network, which itself was guided by the process of identifying essential climate variables. This contribution aims to advance the development of a global biodiversity monitoring strategy by updating the previously published definition of EBV, providing a definition of satellite remote sensing (SRS) EBVs and introducing a set of principles that are believed to be necessary if ecologists and space agencies are to agree on a list of EBVs that can be routinely monitored from space. Progress toward the identification of SRS-EBVs will require a clear understanding of what makes a biodiversity variable essential, as well as agreement on who the users of the SRS-EBVs are. Technological and algorithmic developments are rapidly expanding the set of opportunities for SRS in monitoring biodiversity, and so the list of SRS-EBVs is likely to evolve over time. This means that a clear and common platform for data providers, ecologists, environmental managers, policy makers and remote sensing experts to interact and share ideas needs to be identified to support long-term coordinated actions

New Petro‐aggression in the Middle East: Saudi Arabia in the Spotlight

That hydrocarbon abundance may lead to more violence is an established truism in the literature on the resource curse. Looking at the Middle East, however, the literature relates bellicose state behaviour entirely to oil-producing revolutionary republics. Instead, dynastic monarchies are claimed to be the more peacefully behaving actors. Current developments turn this conclusion upside down, however. Since 2015 at the latest, the foreign policy of Saudi Arabia, the leading monarchy in the Middle East, has transformed from multi-dependence to petro-aggression. By discussing this striking transformation, the paper puts forward a framework looking at the interaction of three crucial dimensions: first, the decreasing power projection towards the Middle East by the United States, the decade-long hegemon, due to gradual changes in world energy markets and war fatigue at home; second, the lasting fiscal potency of the Saudi regime; and, third, the personalization of the Saudi monarchy under King Salman as a historically contingent result of transferring power to the generation of Ibn Saud's grandsons

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy