1,514 research outputs found

    Scattered light mapping of protoplanetary disks

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    High-contrast scattered light observations have revealed the surface morphology of several dozens of protoplanetary disks at optical and near-infrared wavelengths. Inclined disks offer the opportunity to measure part of the phase function of the dust grains that reside in the disk surface which is essential for our understanding of protoplanetary dust properties and the early stages of planet formation. We aim to construct a method which takes into account how the flaring shape of the scattering surface of an (optically thick) protoplanetary disk projects onto the image plane of the observer. This allows us to map physical quantities (scattering radius and scattering angle) onto scattered light images and retrieve stellar irradiation corrected (r^2-scaled) images and dust phase functions. We apply the method on archival polarized intensity images of the protoplanetary disk around HD 100546 that were obtained with VLT/SPHERE in R'-band and VLT/NACO in H- and Ks-band. The brightest side of the r^2-scaled R'-band polarized intensity image of HD 100546 changes from the far to the near side of the disk when a flaring instead of a geometrically flat disk surface is used for the r^2-scaling. The decrease in polarized surface brightness in the scattering angle range of ~40-70 deg is likely a result of the dust phase function and degree of polarization which peak in different scattering angle regimes. The derived phase functions show part of a forward scattering peak which indicates that large, aggregate dust grains dominate the scattering opacity in the disk surface. Projection effects of a protoplanetary disk surface need to be taken into account to correctly interpret scattered light images. Applying the correct scaling for the correction of stellar irradiation is crucial for the interpretation of the images and the derivation of the dust properties in the disk surface layer.Comment: Accepted for publication in A&A, 6 pages, 3 figure

    Organic molecules in the protoplanetary disk of DG Tau revealed by ALMA

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    Planets form in protoplanetary disks and inherit their chemical compositions. It is thus crucial to map the distribution and investigate the formation of simple organics, such as formaldehyde and methanol, in protoplanetary disks. We analyze ALMA observations of the nearby disk-jet system around the T Tauri star DG Tau in the o-H2_2CO 31,2−21,13_{1,2}-2_{1,1} and CH3_3OH 3−2,2−4−1,43_{-2,2}-4_{-1,4} E, 50,5−40,45_{0,5}-4_{0,4} A transitions at an unprecedented resolution of ∼0.15"\sim0.15", i.e., ∼18\sim18 au at a distance of 121 pc. The H2_2CO emission originates from a rotating ring extending from ∼40\sim40 au with a peak at ∼62\sim62 au, i.e., at the edge of the 1.3mm dust continuum. CH3_3OH emission is not detected down to an r.m.s. of 3 mJy/beam in the 0.162 km/s channel. Assuming an ortho-to-para ratio of 1.8-2.8 the ring- and disk-height-averaged H2_2CO column density is ∼0.3−4×1014\sim0.3-4\times10^{14} cm−2^{-2}, while that of CH3_3OH is <0.04−0.7×1014<0.04-0.7\times10^{14} cm−2^{-2}. In the inner 4040 au no o-H2_2CO emission is detected with an upper limit on its beam-averaged column density of ∼0.5−6×1013\sim0.5-6\times10^{13} cm−2^{-2}. The H2_2CO ring in the disk of DG Tau is located beyond the CO iceline (RCO∼30_{\rm CO}\sim30 au). This suggests that the H2_2CO abundance is enhanced in the outer disk due to formation on grain surfaces by the hydrogenation of CO ice. The emission peak at the edge of the mm dust continuum may be due to enhanced desorption of H2_2CO in the gas phase caused by increased UV penetration and/or temperature inversion. The CH3_3OH/H2_2CO abundance ratio is <1<1, in agreement with disk chemistry models. The inner edge of the H2_2CO ring coincides with the radius where the polarization of the dust continuum changes orientation, hinting at a tight link between the H2_2CO chemistry and the dust properties in the outer disk and at the possible presence of substructures in the dust distribution.Comment: 8 pages, 6 figures, accepted for publication on A&A Letter

    AB0704 TELEMEDICINE AT THE TIME OF COVID-19: THE EXPERIENCE WITH RA PATIENTS TREATED WITH JAK-INHIBITORS

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    Background:The spread of COVID-19, the lockdown, the limited access to care reevaluated the role of tele-consultation and self-assessment.Objectives:Our aim was to evaluate in a cohort of Rheumatoid Arthritis (RA) patients treated with JAK-inhibitors (JAKi): the self-assessed disease activity during lockdown, the lockdown impact on fatigue, anxiety, depression and the prevalence of Covid-19.Methods:We enrolled RA patients treated with baricitinib or tofacitinib. At baseline (BL) and follow-up we collected: patients' demographic data, composite disease activity indices (CDAI, DAS28CRP), global assessment (PGA), pain visual analogue scale (VAS), FACIT (functional assessment of chronic illness therapy) and a self-rating scale for disease impact on anxiety and depression (Zung-A/D). Patients were instructed on how to perform self-assessment through video-material and fulfilled the online form of "Rheumatoid Arthritis Impact of Disease" (RAID)1 and "RA Disease Activity Index" (RADAI). To capture the pandemic effect, we compared patients in different status (remission, low, moderate and high-disease activity) at the last in-person visit (preCoV) through the DAS28CRP and CDAI, to the tele-health visit (THV), measured by the RAID. BL and pre-CoV ZUNG-A, ZUNG-D, FACIT questionnaires were compared with the online results during the pandemic. Exposure, tests and symptoms of Covid-19 were recorded. Data were expressed as mean±standard deviation or median(IQR) according to distribution.Results:Twenty patients (median age 58.2±11.9 and mean disease duration 153.5 ± 112.7 months) were treated with tofacitinib and 27 with baricitinib. The median time-lapse between the pre-CoV visit and the THV was 12 (IQR 4) weeks. DAS28CRP and CDAI significantly decreased from BL to pre-CoV visit. During the last in-person visit, 21 patients (48.83%) were in remission, 9 (20.93%) in low disease activity; according to the RAID, 15 (31.91%) and 7 (14.89%) patients were respectively in remission and low disease activity during the THV (Table A). PGA and pain significantly decreased from BL to pre-Cov visit but worsened during the lockdown (Table A). FACIT remaining stable during THV. At THV, we detected a significant improvement of anxiety from BL (Zung-A) and a tendency to lower depression scores compared to BL (Table A). JAKi showed a good safety profile considering Covid-19 symptoms, none of the patients was diagnosed with SarsCoV2 infection.Conclusion:This is the first study on virtual assessment in RA patients treated with JAKi. The unique social experiment of the pandemic impaired the clinical response already achieved before the lockdown, without a collateral worseling of FACIT, anxiety and depression.References:[1]Gossec L, et al. Ann Rheum Dis. 2009[2]Stucki G, et al. Arthritis Rheum. 1995Table A.DAS28, CDAI, RAID scores and patient-reported outcomes assessment at baseline and during the follow-upBLpre-CoVTHVDISEASE ACTIVITYN (%)N (%)N (%)REMISSIONDAS280 (0%)21 (48.8%)CDAI0 (0%)10 (22.7%)RAID15 (31.9%)LOW DISEASEDAS281(2.1%)9 (20.9%)CDAI7(14.8%)23 (52.2%)RAID7 (14.9%)MODERATEDAS2833 (70.2%)12 (27.9%)CDAI17 (37.1%)8 (18.1%)RAID13 (27.6%)HIGHDAS2813 (27.6%)1 (2.3%)CDAI23 (48.9%)3 (6.8%)RAID12 (25.5%)GH70 (30)20 (49.5)*45 (45)*#Pain70 (28)25 (45.5)*40 (48.5)*#Zung A37 (9)37 (10.2)35 (14)*Zung-D39 (17)39 (13)*38 (12)FACIT11.5 (17.2)8 (19.5)7(15)* p≤0.001 vs BL# p ≤0.04vs preCoVData expressed as median (IQR)Disclosure of Interests:Cristina Garufi: None declared, Francesca Romana Spinelli Speakers bureau: Abbvie, Eli Lilly, Consultant of: Gilead/Galapagos, Eli Lilly, Grant/research support from: Pfizer, Silvia Mancuso: None declared, Fulvia Ceccarelli: None declared, Fabrizio Conti Speakers bureau: Abbvie, Eli Lilly, Sanofi, Pfizer, Consultant of: Gilead/Galapago

    Weekly epirubicin plus lonidamine in advanced breast carcinoma

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    : Lonidamine has been demonstrated to potentiate the cytotoxic activity of several antineoplastic drugs, for example anthracyclines. Moreover, epirubicin is considered one of the most active drugs in advanced breast cancer, although optimal dose and schedule remains to be defined. In the present study we have treated 51 patients with advanced breast cancer with a combination of lonidamine (450 mg/day orally from day 1 throughout treatment) and epirubicin (25 mg/m2 i.v.) administered according to a weekly schedule for 24 weeks. Objective responses were observed in 29 out of 51 patients (57%; CR 16%, PR 41%). Liver metastases responded in eight out of 12 evaluable patients (67%). Average response duration was 12.4 months and median overall survival was 23 months (range 1-90+). Toxicity was negligible. The combination of weekly epirubicin and lonidamine is feasible and active in advanced breast cancer patients

    Constraining the mass of the planet(s) sculpting a disk cavity. The intriguing case of 2MASS J16042165-2130284

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    The large cavities observed in the dust and gas distributions of transition disks may be explained by planet-disk interactions. At ~145 pc, 2MASS J16042165-2130284 (J1604) is a 5-12 Myr old transitional disk with different gap sizes in the mm- and μ\mum-sized dust distributions (outer edges at ~79 and at ~63 au, respectively). Its 12^{12}CO emission shows a ~30 au cavity. This radial structure suggests that giant planets are sculpting this disk. We aim to constrain the masses and locations of plausible giant planets around J1604. We observed J1604 with the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) at the Very Large Telescope (VLT), in IRDIFS\_EXT, pupil-stabilized mode, obtaining YJH- band images with the integral field spectrograph (IFS) and K1K2-band images with the Infra-Red Dual-beam Imager and Spectrograph (IRDIS). The dataset was processed exploiting the angular differential imaging (ADI) technique with high-contrast algorithms. Our observations reach a contrast of ΔK,YH\Delta K, YH ~12 mag from 0.15" to 0.80" (~22 to 115 au), but no planet candidate is detected. The disk is directly imaged in scattered light at all bands from Y to K, and it shows a red color. This indicates that the dust particles in the disk surface are mainly ≳0.3 μ\gtrsim0.3\,\mum-sized grains. We confirm the sharp dip/decrement in scattered light in agreement with polarized light observations. Comparing our images with a radiative transfer model we argue that the southern side of the disk is most likely the nearest. This work represents the deepest search yet for companions around J1604. We reach a mass sensitivity of ≳2−3MJup\gtrsim 2-3M_{Jup} from ~22 to ~115 au according to a hot start scenario. We propose that a brown dwarf orbiting inside of ~15 au and additional Jovian planets at larger radii could account for the observed properties of J1604 while explaining our lack of detection.Comment: 10 pages, 7 Figures. Accepted for publication in A&A . Abridged abstrac

    Cetuximab plus chronomodulated irinotecan, 5-fluorouracil, leucovorin and oxaliplatin as neoadjuvant chemotherapy in colorectal liver metastases: POCHER trial

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    Background:We assessed the effectiveness of cetuximab plus chronomodulated irinotecan, 5-fluorouracil (5-FU), leucovorin (FA) and oxaliplatin (L-OHP) (chrono-IFLO) administered as neoadjuvant chemotherapy to increase the resectability of colorectal liver metastases.Methods:This was a phase II prospective trial with rate of liver metastases resection as primary end point. Forty-three patients with unresectable metastases were enroled: 9 with metastases &gt;5 cm; 29 with multinodular (4) disease; 1 with hilar location; 4 with extrahepatic lung disease. Treatment consisted of cetuximab at day 1 plus chronomodulated irinotecan 5-FU, FA and L-OHP for 2-6 days every 2 weeks. After the first 17 patients, doses were reduced for irinotecan to 110 mg m 2, 5-FU to 550 mg m 2 per day and L-OHP to 15 mg m 2 per day.Results:Macroscopically complete resections were performed in 26 out of 43 patients (60%) after a median of 6 (range 3-15) cycles. Partial response was noticed in 34 patients (79%). Median overall survival was 37 months (95% CI: 21-53 months), with a 2-year survival of 68% in the entire population, 80.6% in resected patients and 47.1% in unresected patients (P=0.01). Grade 3/4 diarrhoea occurred in 93% and 36% of patients before and after dose reduction.Conclusion:Cetuximab plus chrono-IFLO achieved 60% complete resectability of colorectal liver metastases. © 2010 Cancer Research UK All rights reserved

    Detection of Sharp Symmetric Features in the Circumbinary Disk Around AK Sco

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    The Search for Planets Orbiting Two Stars (SPOTS) survey aims to study the formation and distribution of planets in binary systems by detecting and characterizing circumbinary planets and their formation environments through direct imaging. With the SPHERE Extreme Adaptive Optics instrument, a good contrast can be achieved even at small (<300 mas) separations from bright stars, which enables studies of planets and disks in a separation range that was previously inaccessible. Here, we report the discovery of resolved scattered light emission from the circumbinary disk around the well-studied young double star AK Sco, at projected separations in the ~13--40 AU range. The sharp morphology of the imaged feature is surprising, given the smooth appearance of the disk in its spectral energy distribution. We show that the observed morphology can be represented either as a highly eccentric ring around AK Sco, or as two separate spiral arms in the disk, wound in opposite directions. The relative merits of these interpretations are discussed, as well as whether these features may have been caused by one or several circumbinary planets interacting with the disk.Comment: 10 pages, 3 figures, accepted for publication in ApJ Letters. Minor (proof-level) corrections implemented in this versio
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