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A super-Earth with atmosphere 'Super-Earths' are extrasolar planets about two to ten times the mass of the Earth, too small to be considered 'Jupiters'. Observations from the MEarth Project — using two 40-cm (16-inch) telescopes that will eventually be part of an eight-telescope array — have now identified a super-Earth (GJ 1214b) transiting a nearby low mass star. GJ 1214b has a mass 6.55 times that of the Earth and a radius of 2.68 'Earths'. As the star is small and only 13 parsecs away, the planetary atmosphere is available for direct study with current observatories. A population of extrasolar planets has been uncovered with minimum masses of 1.9–10 times the Earth's mass, called super-Earths, but atmospheric studies can be precluded by the distance and size of their stars. Here, observations of the transiting planet GJ 1214b are reported; it has a mass 6.55 times that of the Earth and a radius 2.68 times the Earth's radius. The star is small and only 13 parsecs away, permitting the study of the planetary atmosphere with current observatories. A decade ago, the detection of the first 1 , 2 transiting extrasolar planet provided a direct constraint on its composition and opened the door to spectroscopic investigations of extrasolar planetary atmospheres 3 . Because such characterization studies are feasible only for transiting systems that are both nearby and for which the planet-to-star radius ratio is relatively large, nearby small stars have been surveyed intensively. Doppler studies 4 , 5 , 6 and microlensing 7 have uncovered a population of planets with minimum masses of 1.9–10 times the Earth’s mass ( M ⊕ ), called super-Earths. The first constraint on the bulk composition of this novel class of planets was afforded by CoRoT-7b (refs 8 , 9 ), but the distance and size of its star preclude atmospheric studies in the foreseeable future. Here we report observations of the transiting planet GJ 1214b, which has a mass of 6.55 M ⊕ and a radius 2.68 times Earth’s radius ( R ⊕ ), indicating that it is intermediate in stature between Earth and the ice giants of the Solar System. We find that the planetary mass and radius are consistent with a composition of primarily water enshrouded by a hydrogen–helium envelope that is only 0.05% of the mass of the planet. The atmosphere is probably escaping hydrodynamically, indicating that it has undergone significant evolution during its history. The star is small and only 13 parsecs away, so the planetary atmosphere is amenable to study with current observatories.

Recently, an ionized cloud of gas was discovered plunging towards the supermassive black hole, SgrA*, at the centre of the Milky Way. The cloud is being tidally disrupted along its path to closest approach at ∼3,100 Schwarzschild radii from the black hole. Here we show that the observed properties of this cloud of gas can naturally be produced by a proto-planetary disc surrounding a low-mass star, which was scattered from the observed ring of young stars orbiting SgrA*. As the young star approaches the black hole, its disc experiences both photoevaporation and tidal disruption, producing a cloud. Our model implies that planets form in the Galactic centre, and that tidal debris from proto-planetary discs can flag low-mass stars, which are otherwise too faint to be detected. Recent observations have uncovered a cloud of ionized gas falling into the supermassive black hole at the centre of our galaxy. Murray-Clay and Loeb present a model that may explain these observations, in which the cloud is produced from the proto-planetary disc around a low-mass star orbiting the black hole.

Chronic obstructive pulmonary disease (COPD) are managed predominantly in primary care. However, key opportunities to optimize treatment are often not realized due to unrecognized disease and delayed implementation of appropriate interventions for both diagnosed and undiagnosed individuals. The COllaboratioN on QUality improvement initiative for achieving Excellence in STandards of COPD care (CONQUEST) is the first-of-its-kind, collaborative, interventional COPD registry. It comprises an integrated quality improvement program focusing on patients (diagnosed and undiagnosed) at a modifiable and higher risk of COPD exacerbations. The first step in CONQUEST was the development of quality standards (QS). The QS will be imbedded in routine primary and secondary care, and are designed to drive patient-centered, targeted, risk-based assessment and management optimization. Our aim is to provide an overview of the CONQUEST QS, including how they were developed, as well as the rationale for, and evidence to support, their inclusion in healthcare systems. The QS were developed (between November 2019 and December 2020) by the CONQUEST Global Steering Committee, including 11 internationally recognized experts with a specialty and research focus in COPD. The process included an extensive literature review, generation of QS draft wording, three iterative rounds of review, and consensus. Four QS were developed: 1) identification of COPD target population, 2) assessment of disease and quantification of future risk, 3) non-pharmacological and pharmacological intervention, and 4) appropriate follow-up. Each QS is followed by a rationale statement and a summary of current guidelines and research evidence relating to the standard and its components. The CONQUEST QS represent an important step in our aim to improve care for patients with COPD in primary and secondary care. They will help to transform the patient journey, by encouraging early intervention to identify, assess, optimally manage and followup COPD patients with modifiable high risk of future exacerbations.

The increased severity of disease associated with the NAP1 strain of Clostridium difficile has been attributed to mutations to the tcdC gene which codes for a negative regulator of toxin production. To assess the role of hyper-production of Toxins A and B in clinical isolates of Clostridium difficile, two NAP1-related and five NAP1 non-related strains were compared. Sequencing was performed on tcdC, tcdR, and tcdE to determine if there were differences that might account for hyper-production of Toxin A and Toxin B in NAP1-related strains. Biological activity of Toxin B was evaluated using the HFF cell CPE assay and Toxin A biological activity was assessed using the Caco-2 Trans-membrane resistance assay. Our results confirm that Toxin A and Toxin B production in NAP1-related strains and ATCC 43255 occurs earlier in the exponential growth phase compared to most NAP1-nonrelated clinical isolates. Despite the hyper-production observed in ATCC 43255 it had no mutations in tcdC, tcdR or tcdE. Analysis of the other clinical isolates indicated that the kinetics and ultimate final concentration of Toxin A and B did not correlate with the presence or lack of alterations in tcdC, tcdR or tcdE. Our data do not support a direct role for alterations in the tcdC gene as a predictor of hyperproduction of Toxin A and B in NAP1-related strains.

Hereditary influences account for a substantial proportion of the variance in many cognitive abilities. However, there is increasing recognition that the relative importance of genetic and environmental influences may vary across different socioeconomic levels. The overall goal of the present study was to examine whether parental education has a moderating effect on genetic and environmental influences of general cognitive ability in early adulthood (age 19.6 ± 1.5). Participants were 5,955 male twins from the Vietnam Era Twin (VET) Registry. Significant effects of parental education on mean level of general cognitive ability scores were found, but a model without moderating effects of parental education on genetic or environmental influences on cognitive scores proved to be the best fitting model. Some, but not all, previous studies have found significant moderating effects; however, no consistent pattern emerged that could account for between-study differences regarding moderating effects on genetic and environmental influences.

RationaleProgressive lung function (LF) decline in patients with asthma contributes to worse outcomes. Asthma exacerbations are thought to contribute to this decline; however, evidence is limited with mixed results.MethodsThis historical cohort study of a broad asthma patient population in the Optimum Patient Care Research Database, examined asthma patients with 3+eligible post-18th birthday peak expiratory flow rate (PEF) records (primary analysis) or records of forced expiratory flow in 1 s (FEV1) (sensitivity analysis). Adjusted linear growth models tested the association between mean annual exacerbation rate (AER) and LF trajectory.ResultsWe studied 1 09 182 patients with follow-up ranging from 5 to 50 years, of which 75 280 had data for all variables included in the adjusted analyses. For each additional exacerbation, an estimated additional −1.34 L/min PEF per year (95% CI −1.23 to –1.50) were lost. Patients with AERs >2/year and aged 18–24 years at baseline lost an additional −5.95 L/min PEF/year (95% CI −8.63 to –3.28) compared with those with AER 0. These differences in the rate of LF decline between AER groups became progressively smaller as age at baseline increased. The results using FEV1 were consistent with the above.ConclusionTo our knowledge, this study is the largest nationwide cohort of its kind and demonstrates that asthma exacerbations are associated with faster LF decline. This was more prominent in younger patients but was evident in older patients when it was related to lower starting LF, suggesting a persistent deteriorating phenotype that develops in adulthood over time. Earlier intervention with appropriate management in younger patients with asthma could be of value to prevent excessive LF decline.

This book builds on the authors' previous title Understanding and Managing Risk Attitude but this time looks exclusively at the challenges of understanding and managing those attitudes adopted by groups of people when faced with making decisions that they perceive as risky and important. The book makes the link between risk management and decision-making explicit, building on existing work from the economic and risk psychology schools but taking a pragmatic, practitioner-focused approach that is relevant to all decision-making groups in any situation. The insights in Managing Group Risk Attitude are derived from the authors' own applied research. Details of the research methods and findings are included in the book in support of a practical model and steps to manage risk attitude using applied emotional literacy. Ruth Murray-Webster and David Hillson have written a practical book for all decision-makers, supported by actual research by practitioners and underpinned by the seminal research of leading academics.

Background The concept of control is gaining importance in the field of allergic rhinitis (AR), with a visual analogue scale (VAS) score being a validated, easy and attractive tool to evaluate AR symptom control. The doctors’ perception of a VAS score as a good tool for evaluating AR symptom control is unknown, as is the level of AR control perceived by physicians who treat patients. Methods 307 voluntarily selected physicians attending the annual (2013) European Academy of Allergy and Clinical Immunology (EAACI) meeting completed a digital survey. Delegates were asked to (1) estimate how many AR patients/week they saw during the season, (2) estimate the proportion of patients they considered to have well-, partly- and un-controlled AR, (3) communicate how they gauged this control and (4) assess how useful they would find a VAS as a method of gauging control. 257 questionnaires were filled out completely and analysed. Results EAACI delegates reported seeing 46.8 [standard deviation (SD) 68.5] AR patients/week during the season. They estimated that 38.7 % (SD 24.0), 34.2 % (SD 20.2) and 20.0 % (SD 16.34) of their AR patients had well-controlled (no AR symptoms), partly-controlled (some AR symptoms), or un-controlled-(moderate/severe AR symptoms) disease despite taking medication [remainder unknown (7.1 %)]. However, AR control was assessed in many ways, including symptom severity (74 %), frequency of day- and night-time symptoms (67 %), activity impairment (57 %), respiratory function monitoring (nasal and/or lung function; 40 %) and incidence of AR exacerbations (50 %). 91 % of delegates felt a simple VAS would be a useful tool to gauge AR symptom control. Conclusions A substantial portion of patients with AR are perceived as having uncontrolled or partly controlled disease even when treated. A simple VAS score is considered a useful tool to monitor AR control.

A newborn star is encircled by a remnant disc of gas and dust. A fraction of the disc coalesces into planets. Another fraction spirals inward and accretes onto the star 1 . Accreting gas not only produces observed ultraviolet radiation, but also drags along embedded planets, helping to explain otherwise mysterious features of observed extrasolar systems. What drives disc accretion has remained uncertain. The magneto-rotational instability (MRI), driven by coupling between magnetic fields and disc rotation, supplies a powerful means of transport 2 , but protoplanetary disc gas might be too poorly ionized to couple to magnetic fields 1 , 2 , 3 , 4 , 5 , 6 . Here we show that the MRI explains the observed accretion rates of newly discovered transitional discs 7 , 8 , which are swept clean of dust inside rim radii of ∼10  AU . Stellar coronal X-rays ionize the disc rim, activating the MRI there. Gas flows steadily from the rim to the star, at a rate set by the depth to which X-rays ionize the rim wall. Blown out by radiation pressure, dust largely fails to accrete with gas. Our picture supplies one concrete setting for theories of how planets grow and have their orbits shaped by disc gas 9 , and when combined with photo-evaporative disc winds 10 provides a framework for understanding how discs dissipate.

Empirical constraints of fundamental properties of protoplanetary disks are essential for understanding planet formation and planetary properties 1 , 2 . Carbon monoxide (CO) gas is often used to constrain disk properties 3 . However, estimates show that the CO gas abundance in disks is depleted relative to expected values 4 – 7 , and models of various disk processes impacting the CO abundance could not explain this depletion on observed ~1 Myr timescales 8 – 14 . Here we demonstrate that surface energy effects on particles in disks, such as the Kelvin effect, that arise when ice heterogeneously nucleates onto an existing particle can efficiently trap CO in its ice phase. In previous ice formation models, CO gas was released when small ice-coated particles were lofted to warmed disk layers. Our model can reproduce the observed abundance, distribution and time evolution of gaseous CO in the four most studied protoplanetary disks 7 . We constrain the solid and gaseous CO inventory at the midplane and disk diffusivities and resolve inconsistencies in estimates of the disk mass—three crucial parameters that control planetary formation. A model of CO ice formation in protoplanetary disks shows that surface energy effects, such as the Kelvin effect, in ice nucleation and condensation must be considered to reproduce the observed distribution, abundances and evolution of gaseous CO.