Context. The SPHERE “planet finder” is an extreme adaptive optics (AO) instrument for high resolution and high contrast observations at the Very Large Telescope (VLT). We describe the Zurich Imaging ...Polarimeter (ZIMPOL), the visual focal plane subsystem of SPHERE, which pushes the limits of current AO systems to shorter wavelengths, higher spatial resolution, and much improved polarimetric performance. Aims. We present a detailed characterization of SPHERE/ZIMPOL which should be useful for an optimal planning of observations and for improving the data reduction and calibration. We aim to provide new benchmarks for the performance of high contrast instruments, in particular for polarimetric differential imaging. Methods. We have analyzed SPHERE/ZIMPOL point spread functions (PSFs) and measure the normalized peak surface brightness, the encircled energy, and the full width half maximum (FWHM) for different wavelengths, atmospheric conditions, star brightness, and instrument modes. Coronagraphic images are described and the peak flux attenuation and the off-axis flux transmission are determined. Simultaneous images of the coronagraphic focal plane and the pupil plane are analyzed and the suppression of the diffraction rings by the pupil stop is investigated. We compared the performance at small separation for different coronagraphs with tests for the binary α Hyi with a separation of 92 mas and a contrast of Δm ≈ 6m. For the polarimetric mode we made the instrument calibrations using zero polarization and high polarization standard stars and here we give a recipe for the absolute calibration of polarimetric data. The data show small (< 1 mas) but disturbing differential polarimetric beam shifts, which can be explained as Goos-Hähnchen shifts from the inclined mirrors, and we discuss how to correct this effect. The polarimetric sensitivity is investigated with non-coronagraphic and deep, coronagraphic observations of the dust scattering around the symbiotic Mira variable R Aqr. Results. SPHERE/ZIMPOL reaches routinely an angular resolution (FWHM) of 22−28 mas, and a normalized peak surface brightness of SB0 − mstar ≈ −6.5m arcsec−2 for the V-, R- and I-band. The AO performance is worse for mediocre ≳1.0″ seeing conditions, faint stars mR ≳ 9m, or in the presence of the “low wind” effect (telescope seeing). The coronagraphs are effective in attenuating the PSF peak by factors of > 100, and the suppression of the diffracted light improves the contrast performance by a factor of approximately two in the separation range 0.06″−0.20″. The polarimetric sensitivity is Δp < 0.01% and the polarization zero point can be calibrated to better than Δp ≈ 0.1%. The contrast limits for differential polarimetric imaging for the 400 s I-band data of R Aqr at a separation of ρ = 0.86″ are for the surface brightness contrast SBpol( ρ)−mstar ≈ 8m arcsec−2 and for the point source contrast mpol( ρ)−mstar ≈ 15m and much lower limits are achievable with deeper observations. Conclusions. SPHERE/ZIMPOL achieves imaging performances in the visual range with unprecedented characteristics, in particular very high spatial resolution and very high polarimetric contrast. This instrument opens up many new research opportunities for the detailed investigation of circumstellar dust, in scattered and therefore polarized light, for the investigation of faint companions, and for the mapping of circumstellar Hα emission.
The impact of stellar multiplicity on the evolution of planet-forming disks is still the subject of debate. Here we present and analyze disk structures around ten multiple stellar systems that were ...included in an unbiased, high spatial resolution survey performed with ALMA of 32 protoplanetary disks in the Taurus star-forming region. At the unprecedented spatial resolution of ~0.12′′ we detect and spatially resolve the disks around all primary stars, and those around eight secondary and one tertiary star. The dust radii of disks around multiple stellar systems are smaller than those around single stars in the same stellar mass range and in the same region. The disks in multiple stellar systems also show a steeper decay of the millimeter continuum emission at the outer radius than disks around single stars, suggestive of the impact of tidal truncation on the shape of the disks in multiple systems. However, the observed ratio between the dust disk radii and the observed separation of the stars in the multiple systems is consistent with analytic predictions of the effect of tidal truncation only if the eccentricities of the binaries are rather high (typically >0.5) or if the observed dust radii are a factor of two smaller than the gas radii, as is typical for isolated systems. Similar high-resolution studies targeting the gaseous emission from disks in multiple stellar systems are required to resolve this question.
ABSTRACT We present the results of ALMA band 7 observations of dust and CO gas in the disks around 7 objects with spectral types ranging between M5.5 and M7.5 in Upper Scorpius OB1, and one M3 star ...in Ophiuchus. We detect unresolved continuum emission in all but one source, and the 12CO J = 3 − 2 line in two sources. We constrain the dust and gas content of these systems using a grid of models calculated with the radiative transfer code MCFOST, and find disk dust masses between 0.1 and 1 M⊕, suggesting that the stellar mass/disk mass correlation can be extrapolated for brown dwarfs (BDs) with masses as low as 0.05 M . The one disk in Upper Sco in which we detect CO emission, 2MASS J15555600, is also the disk with the warmest inner disk, as traced by its H-4.5 photometric color. Using our radiative transfer grid, we extend the correlation between stellar luminosity and mass-averaged disk dust temperature, originally derived for stellar mass objects, to the BD regime to , applicable to spectral types of M5 and later. This is slightly shallower than the relation for earlier spectral type objects and yields warmer low-mass disks. The two prescriptions cross at 0.27 L , corresponding to masses between 0.1 and 0.2 M depending on age.
Abstract Fecal calprotectin (FC) is a simple, non-invasive and reproducible test, which has been described to be highly elevated in patients with active inflammatory bowel diseases. Recently, few ...authors have reported increased levels of FC in SSc patients, although the relationship between FC levels and the degree of gastrointestinal involvement has not yet been determined in patients with SSc. Thus, this prospective study aimed to: 1) determine the prevalence of increased fecal calprotectin (FC) levels in unselected patients with systemic sclerosis (SSc); 2) make prediction about which SSc patients exhibit increased levels of FC; and 3) evaluate the correlation between increased levels of FC and digestive symptoms, and gastrointestinal involvement, including the presence of small intestinal bacterial overgrowth (SIBO) using glucose H2 /CH4 breath test. 125 consecutive patients with SSc underwent FC levels and glucose H2 /CH4 breath test. All of the patients with SSc also completed a questionnaire on digestive symptoms, and a global symptom score (GSS) was calculated. 93 (74.4%) patients had abnormal levels of FC (> 50 μg/g); 68 patients (54.4%) exhibited highly elevated levels of FC (> 200 μg/g). A marked correlation was found between abnormal FC levels and GSS score of digestive symptoms, esophageal involvement and delayed gastric emptying. Moreover, we found a strong association between abnormal levels of FC and the presence of SIBO on glucose H2 /CH4 breath test, with the higher correlation between the presence of SIBO and the level of FC ≥ 275 μg/g with an area under the receiver operating characteristic curve of 0.97 ± 0.001 (CI: 0.93–0.99; p < 10 − 6 ); the sensitivity of FC level ≥ 275 μg/g for predicting SIBO was as high as 0.93, while the specificity was 0.95. Finally, eradication of SIBO was obtained in 52.4% of the SSc patients with a significant improvement of intestinal symptoms. Finally, after 3 months of rotating courses of alternative antibiotic therapy, eradication of SIBO was associated with significant decrease of FC levels in SSc patients. The current study underscores that abnormal FC levels were correlated with gastrointestinal impairment, especially SIBO. Because FC levels ≥ 275 μg/g were markedly associated with the presence of SIBO, our findings suggest that FC may be a helpful test in identifying the group of SSc patients at high risk for SIBO requiring glucose breath test to detect SIBO. Finally, we also suggest that FC levels may be helpful in SSc patients to assess SIBO eradication, as long-term antibiotic therapy is costly and carries risks such as the onset of pseudo-membranous colitis and SIBO-related antibiotic resistance.
Abstract The aims of the present study were to: compare the characteristics between antisynthetase syndrome (ASS) patients with anti-Jo1 antibody and those with anti-PL7/PL12 antibody. The medical ...records of 95 consecutive patients with ASS were reviewed. Seventy-five of these patients had anti-Jo1 antibody; the other patients had anti-PL7 (n = 15) or anti-PL12 (n = 5) antibody. At ASS diagnosis, the prevalence of myalgia (p = 0.007) and muscle weakness (p = 0.02) was significantly lower in the group of anti-PL7/PL12-positive patients than in those with anti-Jo1 antibody; median value of CK (p = 0.00003) was also lower in anti-PL7/PL12 patients. Anti-Jo1 positive patients developed more rarely myositis resolution (21.3% vs. 46.2%); in addition, the overall recurrence rate of myositis was higher in anti-Jo1 positive patients than in patients with anti-PL7/PL12 antibody (65.9% vs. 19.4%). Anti-Jo1-positive patients, compared with those with anti-PL7/PL12 antibody, more often experienced: joint involvement (63.3%vs. 40%) and cancer (13.3% vs. 5%). By contrast, anti-PL7/PL12 positive patients, compared with those with anti-Jo1 antibody, more commonly exhibited: ILD (90% vs. 68%); in anti-PL7/PL12 positive patients, ILD was more often symptomatic at diagnosis, and led more rarely to resolution of lung manifestations (5.6% vs. 29.4%). Finally, the group of anti-PL7/PL12 positive patients more commonly experienced gastrointestinal manifestations related to ASS (p = 0.02). Taken together, although anti-Jo1 positive patients with ASS share some features with those with anti-PL7/PL12 antibody, they exhibit many differences regarding clinical phenotype and long-term outcome. Our study underscores that the presence of anti-Jo1 antibody results in more severe myositis, joint impairment and increased risk of cancer. On the other hand, the presence of anti-PL7/PL12 antibody is markedly associated with: early and severe ILD, and gastrointestinal complications. Thus, our study interestingly indicates that the finding for anti-Jo1 and anti-PL7/PL12 antibodies impacts both the long-term outcome and prognosis of patients with ASS.
We present scattered light images of the TW Hya disk performed with the Spectro-Polarimetric High-contrast Exoplanet REsearch instrument in Polarimetric Differential Imaging mode at 0.63, 0.79, 1.24, ...and 1.62 m. We also present H2/H3-band angular differential imaging (ADI) observations. Three distinct radial depressions in the polarized intensity distribution are seen, around 85, 21, and 6 au.21 The overall intensity distribution has a high degree of azimuthal symmetry; the disk is somewhat brighter than average toward the south and darker toward the north-west. The ADI observations yielded no signifiant detection of point sources in the disk. Our observations have a linear spatial resolution of 1-2 au, similar to that of recent ALMA dust continuum observations. The sub-micron-sized dust grains that dominate the light scattering in the disk surface are strongly coupled to the gas. We created a radiative transfer disk model with self-consistent temperature and vertical structure iteration and including grain size-dependent dust settling. This method may provide independent constraints on the gas distribution at higher spatial resolution than is feasible with ALMA gas line observations. We find that the gas surface density in the "gaps" is reduced by 50% to 80% relative to an unperturbed model. Should embedded planets be responsible for carving the gaps then their masses are at most a few 10 . The observed gaps are wider, with shallower flanks, than expected for planet-disk interaction with such low-mass planets. If forming planetary bodies have undergone collapse and are in the "detached phase," then they may be directly observable with future facilities such as the Mid-Infrared E-ELT Imager and Spectrograph at the E-ELT.
Objective
To assess the long‐term outcome of esophageal complications in the group of patients receiving intravenous immunoglobulins (IVIG) for the treatment of severe steroid‐refractory esophageal ...involvement related to polymyositis/dermatomyositis (PM/DM).
Methods
We retrospectively reviewed the medical records of 73 patients (39 with PM, 34 with DM) with steroid‐resistant esophageal involvement. Esophageal involvement was evaluated by clinical and manometric investigations.
Results
Seventy‐three patients with steroid‐refractory esophageal involvement related to PM/DM received IVIG therapy (2 gm/kg monthly). The median interval between PM/DM diagnosis and the onset of esophageal complications was 6 months. The most common clinical manifestations revealing esophageal dysfunction were dysphagia (69.9%), coughing while eating (61.6%), and gastroesophageal reflux into the pharynx and/or mouth (34.2%). Twenty‐five patients exhibited life‐threatening esophageal complications requiring exclusive enteral feeding; 33 patients (45.2%) with esophageal impairment developed aspiration pneumonia. Sixty patients (82.2%) exhibited resolution of esophageal clinical manifestations, leading to a return to normal oral feeding and ablation of feeding enteral tubes. Four other patients (5.5%) improved, although they still experienced mild dysphagia intermittently. Because of impaired cricopharyngeal muscle relaxation, another patient successfully underwent cricopharyngeal myotomy. Eight patients died from aspiration pneumonia (n = 6) and cancer (n = 2). Muscle weakness, thoracic myopathy, and aspiration pneumonia were independent predictive factors of IVIG‐treated esophageal complications in PM/DM patients.
Conclusion
Our findings indicate that IVIG should be considered in life‐threatening esophageal impairment complicating steroid‐resistant PM/DM. We also suggest that combined therapy of IVIG and high‐dose steroids may be the first‐line therapy in PM/DM patients with life‐threatening esophageal manifestations.
Context. Understanding the diversity of planets requires studying the morphology and physical conditions in the protoplanetary disks in which they form. Aims. We aim to study the structure of the ~10 ...Myr old protoplanetary disk HD 100453, to detect features that can trace disk evolution and to understand the mechanisms that drive these features. Methods. We observed HD 100453 in polarized scattered light with VLT/SPHERE at optical (0.6 μm, 0.8 μm) and near-infrared (1.2 μm) wavelengths, reaching an angular resolution of ~0.02′′, and an inner working angle of ~0.09′′. Results. We spatially resolve the disk around HD 100453, and detect polarized scattered light up to ~0.42′′ (~48 au). We detect a cavity, a rim with azimuthal brightness variations at an inclination of ~38° with respect to our line of sight, two shadows and two symmetric spiral arms. The spiral arms originate near the location of the shadows, close to the semi major axis. We detect a faint feature in the SW that can be interpreted as the scattering surface of the bottom side of the disk, if the disk is tidally truncated by the M-dwarf companion currently seen at a projected distance of ~119 au. We construct a radiative transfer model that accounts for the main characteristics of the features with an inner and outer disk misaligned by ~72°. The azimuthal brightness variations along the rim are well reproduced with the scattering phase function of the model. While spirals can be triggered by the tidal interaction with the companion, the close proximity of the spirals to the shadows suggests that the shadows could also play a role. The change in stellar illumination along the rim induces an azimuthal variation of the scale height that can contribute to the brightness variations. Conclusions. Dark regions in polarized images of transition disks are now detected in a handful of disks and often interpreted as shadows due to a misaligned inner disk. However, the origin of such a misalignment in HD 100453, and of the spirals, is still unclear, and might be due to a yet-undetected massive companion inside the cavity, and on an inclined orbit. Observations over a few years will allow us to measure the spiral pattern speed, and determine if the shadows are fixed or moving, which may constrain their origin.
ABSTRACT
HD 163296 is a Herbig Ae/Be star known to host a protoplanetary disc with a ringed structure. To explain the disc features, previous works proposed the presence of planets embedded into the ...disc. We have observed HD 163296 with the near-infrared (NIR) branch of SPHERE composed by IRDIS (InfraRed Dual-band Imager and Spectrograph) and IFS (integral field spectrograph) with the aim to put tight constraints on the presence of substellar companions around this star. Despite the low rotation of the field of view during our observation we were able to put upper mass limits of few MJup around this object. These limits do not allow to give any definitive conclusion about the planets proposed through the disc characteristics. On the other hand, our results seem to exclude the presence of the only candidate proposed until now using direct imaging in the NIR even if some caution has to be taken considered the different wavelength bands of the two observations.
Aims. The aim of this work is to study the structure of the protoplanetary disk surrounding the Herbig Ae star HD 163296. Methods. We used high-resolution and high-sensitivity ALMA observations of ...the CO(3–2) emission line and the continuum at 850 μm, as well as the three-dimensional Monte Carlo radiative transfer code, MCFOST, to model the data presented in this work. Results. The CO(3–2) emission unveils for the first time at submillimeter frequencies the vertical structure details of a gaseous disk in Keplerian rotation, showing the back and front sides of a flared disk. Continuum emission at 850 μm reveals a compact dust disk with a 240 AU outer radius and a surface brightness profile that shows a very steep decline at radius larger than 125 AU. The gaseous disk is more than two times larger than the dust disk, with a similar critical radius but with a shallower radial profile. Radiative transfer models of the continuum data confirm the need for a sharp outer edge to the dust disk. The models for the CO(3–2) channel map require the disk to be slightly more geometrically thick than previous models suggested, and that the temperature at which CO gas becomes depleted (i.e., frozen out) from the outer regions of the disk midplane is T < 20 K, in agreement with previous studies.
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