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The radial velocities of a young star are measured, revealing the presence of a planet of mass about three-quarters that of Jupiter, orbiting its host star very closely, and thus demonstrating that ‘hot Jupiters’ can migrate inwards in less than two million years. An inwardly migrating hot Jupiter Jean-François Donati et al . present evidence for a close-in giant planet (hot Jupiter) orbiting the 2-million-year-old Sun-like star V830 Tau. It is thought that hot Jupiters form in the outer part of the primordial disk from which both the central star and surrounding planets are born, and then migrate inwards. This new finding supports that theory by demonstrating the formation and rapid inward migration of a hot Jupiter around a young star. Hot Jupiters are giant Jupiter-like exoplanets that orbit their host stars 100 times more closely than Jupiter orbits the Sun. These planets presumably form in the outer part of the primordial disk from which both the central star and surrounding planets are born, then migrate inwards and yet avoid falling into their host star 1 . It is, however, unclear whether this occurs early in the lives of hot Jupiters, when they are still embedded within protoplanetary disks 2 , or later, once multiple planets are formed and interact 3 . Although numerous hot Jupiters have been detected around mature Sun-like stars, their existence has not yet been firmly demonstrated for young stars 4 , 5 , 6 , whose magnetic activity is so intense that it overshadows the radial velocity signal that close-in giant planets can induce. Here we report that the radial velocities of the young star V830 Tau exhibit a sine wave of period 4.93 days and semi-amplitude 75 metres per second, detected with a false-alarm probability of less than 0.03 per cent, after filtering out the magnetic activity plaguing the spectra. We find that this signal is unrelated to the 2.741-day rotation period of V830 Tau and we attribute it to the presence of a planet of mass 0.77 times that of Jupiter, orbiting at a distance of 0.057 astronomical units from the host star. Our result demonstrates that hot Jupiters can migrate inwards in less than two million years, probably as a result of planet–disk interactions 2 .

The European FP7 project DIANA has performed a coherent analysis of a large set of observational data of protoplanetary disks by means of thermo-chemical disk models. The collected data include extinction-corrected stellar UV and X-ray input spectra (as seen by the disk), photometric fluxes, low and high resolution spectra, interferometric data, emission line fluxes, line velocity profiles and line maps, which probe the dust, polycyclic aromatic hydrocarbons (PAHs) and the gas in these objects. We define and apply a standardized modeling procedure to fit these data by state-of-the-art modeling codes ( ProDiMo , MCFOST , MCMax ), solving continuum and line radiative transfer (RT), disk chemistry, and the heating and cooling balance for both the gas and the dust. 3D diagnostic RT tools (e.g., FLiTs) are eventually used to predict all available observations from the same disk model, the DIANA-standard model. Our aim is to determine the physical parameters of the disks, such as total gas and dust masses, the dust properties, the disk shape, and the chemical structure in these disks. We allow for up to two radial disk zones to obtain our best-fitting models that have about 20 free parameters. This approach is novel and unique in its completeness and level of consistency. It allows us to break some of the degeneracies arising from pure Spectral Energy Distribution (SED) modeling. In this paper, we present the results from pure SED fitting for 27 objects and from the all inclusive DIANA-standard models for 14 objects. Our analysis shows a number of Herbig Ae and T Tauri stars with very cold and massive outer disks which are situated at least partly in the shadow of a tall and gas-rich inner disk. The disk masses derived are often in excess to previously published values, since these disks are partially optically thick even at millimeter wavelength and so cold that they emit less than in the Rayleigh–Jeans limit. We fit most infrared to millimeter emission line fluxes within a factor better than 3, simultaneously with SED, PAH features and radial brightness profiles extracted from images at various wavelengths. However, some line fluxes may deviate by a larger factor, and sometimes we find puzzling data which the models cannot reproduce. Some of these issues are probably caused by foreground cloud absorption or object variability. Our data collection, the fitted physical disk parameters as well as the full model output are available to the community through an online database ( http://www.univie.ac.at/diana ).

Characteristics of the tropical oceanic environment (low productivity, little seasonality) and poor diversity of tropical seabird foraging methods and prey relative to temperate and polar species suggest that tropical seabirds overall encompass a narrow range of isotopic niches, with large overlaps among species. To test this hypothesis, we examined the stable carbon (δ13C) and nitrogen (δ15N) isotopic composition of blood and feathers of 5 seabird species from Europa Island, Mozambique Channel. While differences were small, blood δ13C and δ15N values characterized 5 distinct and non-overlapping trophic niches during the breeding period. Seabirds used 2 distinct foraging areas (δ13C), one used by sooty ternSterna fuscataand white-tailed tropicbirdPhaethon lepturusand one used by red-footed boobySula sulaand greatFregata minorand lesserF. arielfrigatebirds. Seabird species overall encompassed less than 1 trophic level (δ15N), which is in agreement with a diet mainly based on flying fish and squid. Feather δ13C and δ15N values showed that the trophic structure of the community was different during the breeding and non-breeding (moulting) periods, suggesting a shift in the feeding ecology when adult birds were no longer central-place foragers. The stable isotope method underlined sex-related (red-footed booby) and age-related (great frigatebird immatures and adults) feeding strategies. It also suggested that breeding adults could feed themselves on different prey than those given to their chicks (sooty tern). Within the tropical pelagic ecosystem, seabirds overall shared the same trophic level as large predatory fishes (albacore, yellowfin and skipjack tunas), but they had lower δ15N values than the deeper-dwelling bigeye tuna and swordfish. We conclude that analyzing stable isotope values in blood and feathers appears to be a promising alternative method for investigating food and feeding ecology of tropical seabirds year round, and for determining sex- and age-related differences in their foraging strategies. A limitation of the method is the lack of information on marine isoscapes; future studies aimed at isotopically characterizing the tropical marine environment could help to associate consumer signatures to geographic origins.

The objective of this study was to show that although transcutaneous electrical tibial nerve stimulation (TENS) is being increasingly used to treat fecal incontinence (FI), its efficacy has never been proved using controlled trials. In this randomized, double-blind, sham-controlled trial, 144 patients aged 30-82 years from nine centers were randomly assigned to receive either active or sham stimulations for 3 months. The primary end point was the response to treatment based on the number of incontinence and urgency episodes. Secondary end points were severity scores, quality of life scores, delay to postpone defecation, patient self-assessment of treatment efficacy, physician assessment of TENS efficacy, anorectal manometry, and adverse events. No statistically significant difference was seen between active and sham TENS in terms of an improvement in the median number of FI/urgency episodes per week. Thirty-four patients (47%) who received the active TENS treatment exhibited a >30% decrease in the FI severity score compared with 19 patients (27%) who received the sham treatment (odds ratio 2.4, 95% confidence interval 1.1-5.1, P=0.02). No differences in delay to postpone defecation, patient self-assessment of treatment efficacy, or anorectal manometry were seen between the two groups. The evaluating physicians rated the active stimulations as more effective than the sham stimulations (P=0.01). One minor therapy-related adverse event was observed (1.5%) (see Supplementary Consort 1b). We failed to demonstrate any benefit of TENS on our primary end-point.

The patterns of variations in fisheries time series are known to result from a complex combination of species and fisheries dynamics all coupled with environmental forcing (including climate, trophic interactions, etc.). Disentangling the relative effects of these factors has been a major goal of fisheries science for both conceptual and management reasons. By examining the variability of 169 tuna and billfish time series of catch and catch per unit effort (CPUE) throughout the Atlantic as well as their linkage to the North Atlantic Oscillation (NAO), we find that the importance of these factors differed according to the spatial scale. At the scale of the entire Atlantic the patterns of variations are primarily spatially structured, whereas at a more regional scale the patterns of variations were primarily related to the fishing gear. Furthermore, the NAO appeared to also structure the patterns of variations of tuna time series, especially over the North Atlantic. We conclude that the patterns of variations in fisheries time series of tuna and billfish only poorly reflect the underlying dynamics of these fish populations; they appear to be shaped by several successive embedded processes, each interacting with each other. Our results emphasize the necessity for scientific data when investigating the population dynamics of large pelagic fishes, because CPUE fluctuations are not directly attributable to change in species' abundance.

ABSTRACT We describe a large-scale far-infrared line and continuum survey of protoplanetary disk through to young debris disk systems carried out using the ACS instrument on the Herschel Space Observatory. This Open Time Key program, known as GASPS (Gas Survey of Protoplanetary Systems), targeted ∼250 young stars in narrow wavelength regions covering the [OI] fine structure line at 63 μm the brightest far-infrared line in such objects. A subset of the brightest targets were also surveyed in [OI]145 μm, [CII] at 157 μm, as well as several transitions of H2O and high-excitation CO lines at selected wavelengths between 78 and 180 μm. Additionally, GASPS included continuum photometry at 70, 100 and 160 μm, around the peak of the dust emission. The targets were SED Class II-III T Tauri stars and debris disks from seven nearby young associations, along with a comparable sample of isolated Herbig AeBe stars. The aim was to study the global gas and dust content in a wide sample of circumstellar disks, combining the results with models in a systematic way. In this overview paper we review the scientific aims, target selection and observing strategy of the program. We summarise some of the initial results, showing line identifications, listing the detections, and giving a first statistical study of line detectability. The [OI] line at 63 μm was the brightest line seen in almost all objects, by a factor of ∼10. Overall [OI]63 μm detection rates were 49%, with 100% of HAeBe stars and 43% of T Tauri stars detected. A comparison with published disk dust masses (derived mainly from sub-mm continuum, assuming standard values of the mm mass opacity) shows a dust mass threshold for [OI]63 μm detection of ∼10-5 M⊙. Normalising to a distance of 140 pc, 84% of objects with dust masses ≥10-5 M⊙ can be detected in this line in the present survey; 32% of those of mass 10-6-10-5 M⊙, and only a very small number of unusual objects with lower masses can be detected. This is consistent with models with a moderate UV excess and disk flaring. For a given disk mass, [OI] detectability is lower for M stars compared with earlier spectral types. Both the continuum and line emission was, in most systems, spatially and spectrally unresolved and centred on the star, suggesting that emission in most cases was from the disk. Approximately 10 objects showed resolved emission, most likely from outflows. In the GASPS sample, [OI] detection rates in T Tauri associations in the 0.3-4 Myr age range were ∼50%. For each association in the 5-20 Myr age range, ∼2 stars remain detectable in [OI]63 μm, and no systems were detected in associations with age >20 Myr. Comparing with the total number of young stars in each association, and assuming a ISM-like gas/dust ratio, this indicates that ∼18% of stars retain a gas-rich disk of total mass ∼1 MJupiter for 1-4 Myr, 1-7% keep such disks for 5-10 Myr, but none are detected beyond 10-20 Myr. The brightest [OI] objects from GASPS were also observed in [OI]145 μm, [CII]157 μm and CO J = 18 - 17, with detection rates of 20-40%. Detection of the [CII] line was not correlated with disk mass, suggesting it arises more commonly from a compact remnant envelope.

Global-scale studies of marine food webs are rare, despite their necessity for examining and understanding ecosystem level effects of climate variability. Here we review the progress of an international collaboration that compiled regional diet datasets of multiple top predator fishes from the Indian, Pacific and Atlantic Oceans and developed new statistical methods that can be used to obtain a comprehensive ocean-scale understanding of food webs and climate impacts on marine top predators. We loosely define top predators not as species at the apex of the food web, but rather a guild of large predators near the top of the food web. Specifically, we present a framework for world-wide compilation and analysis of global stomach-contents and stable-isotope data of tunas and other large pelagic predatory fishes. To illustrate the utility of the statistical methods, we show an example using yellowfin tuna in a “test” area in the Pacific Ocean. Stomach-contents data were analyzed using a modified (bagged) classification tree approach, which is being prepared as an R statistical software package. Bulk δ 15 N values of yellowfin tuna muscle tissue were examined using a Generalized Additive Model, after adjusting for spatial differences in the δ 15 N values of the baseline primary producers predicted by a global coupled ocean circulation-biogeochemical-isotope model. Both techniques in tandem demonstrated the capacity of this approach to elucidate spatial patterns of variations in both forage species and predator trophic positions and have the potential to predict responses to climate change. We believe this methodology could be extended to all marine top predators. Our results emphasize the necessity for quantitative investigations of global-scale datasets when evaluating changes to the food webs underpinning top ocean predators under long-term climatic variability.

We still do not understand how planets form or why extrasolar planetary systems are so different from our own Solar System. However, the past few years have dramatically changed our view of the disks of gas and dust around young stars. Observations with the Atacama Large Millimeter/submillimeter Array and extreme adaptive-optics systems have revealed that most—if not all—disks contain substructure, including rings and gaps1–3, spirals4–6, azimuthal dust concentrations7 and shadows cast by misaligned inner disks5,8. These features have been interpreted as signatures of newborn protoplanets, but the exact origin is unknown. Here we report the kinematic detection of a few-Jupiter-mass planet located in a gas and dust gap at 130 au in the disk surrounding the young star HD 97048. An embedded planet can explain both the disturbed Keplerian flow of the gas, detected in CO lines, and the gap detected in the dust disk at the same radius. While gaps appear to be a common feature in protoplanetary disks2,3, we present a direct correspondence between a planet and a dust gap, indicating that at least some gaps are the result of planet–disk interactions.Pinte et al. report the kinematic detection of a few-Jupiter-mass planet orbiting at 130 au from the young star HD 97048. The radial position of the planet coincides with a gap in both the gas and dust components of the protoplanetary disk, showing that at least some gaps can be linked to the presence of planets.

For a comprehensive understanding of planetary formation and evolution, we need to investigate the environment in which planets form: circumstellar disks. Here we present high-contrast imaging observations of V4046 Sagittarii, a 20-Myr-old close binary known to host a circumbinary disk. We have discovered the presence of rotating shadows in the disk, caused by mutual occultations of the central binary. Shadow-like features are often observed in disks1,2, but those found thus far have not been due to eclipsing phenomena. We have used the phase difference due to light travel time to measure the flaring of the disk and the geometrical distance of the system. We calculate a distance that is in very good agreement with the value obtained from the Gaia mission’s Data Release 2 (DR2), and flaring angles of α = (6.2 ± 0.6)° and α = (8.5 ± 1.0)° for the inner and outer disk rings, respectively. Our technique opens up a path to explore other binary systems, providing an independent estimate of distance and the flaring angle, a crucial parameter for disk modelling.Moving shadows have been seen on the circumbinary disk around V4046 Sgr, cast by eclipses of the central binary system. Using geometrical arguments, the degree of flaring of the disk and the distance to the system have been calculated.

DNA sequence variations within the 22q11 DiGeorge chromosomal region are likely to confer susceptibility to psychotic disorders. In a previous report, we identified several heterozygous alterations, including a complete deletion, of the proline dehydrogenase ( PRODH) gene, which were associated with moderate hyperprolinemia in a subset of DSM III schizophrenic patients. Our objective was (i) to determine whether hyperprolinemia is associated with increased susceptibility for any of three psychiatric conditions (schizophrenia, schizoaffective disorder and bipolar disorder) and (ii) to establish a correlation between hyperprolinemia and PRODH genotypes. We have conducted a case–control study including 114 control subjects, 188 patients with schizophrenia, 63 with schizoaffective disorder and 69 with bipolar disorder. We report that, taking into account a confounding effect due to valproate treatment, hyperprolinemia is a risk factor for DSM IIIR schizoaffective disorder ( P =0.02, Odds ratio=4.6, 95% confidence interval 1.3–16.3). We did not detect 22q11 interstitial deletions associated with the DiGeorge syndrome among the 320 patients of our sample and we found no association between common PRODH polymorphisms and any of the psychotic disorders. In contrast, we found that five rare PRODH alterations (including a complete PRODH deletion and four missense substitutions) were associated with hyperprolinemia. In several cases, two variations were present simultaneously, either in cis or trans in the same subject. A total of 11 from 30 hyperprolinemic subjects bore at least one genetic variation associated with hyperprolinemia. This study demonstrates that moderate hyperprolinemia is an intermediate phenotype associated with certain forms of psychosis.