Phase Referencing in Optical Interferometry

One of the aims of next generation optical interferometric instrumentation is to be able to make use of information contained in the visibility phase to construct high dynamic range images. Radio and optical interferometry are at the two extremes of phase corruption by the atmosphere. While in radio it is possible to obtain calibrated phases for the science objects, in the optical this is currently not possible. Instead, optical interferometry has relied on closure phase techniques to produce images. Such techniques allow only to achieve modest dynamic ranges. However, with high contrast objects, for faint targets or when structure detail is needed, phase referencing techniques as used in radio interferometry, should theoretically achieve higher dynamic ranges for the same number of telescopes. Our approach is not to provide evidence either for or against the hypothesis that phase referenced imaging gives better dynamic range than closure phase imaging. Instead we wish to explore the potential of this technique for future optical interferometry and also because image reconstruction in the optical using phase referencing techniques has only been performed with limited success. We have generated simulated, noisy, complex visibility data, analogous to the signal produced in radio interferometers, using the VLTI as a template. We proceeded with image reconstruction using the radio image reconstruction algorithms contained in AIPS IMAGR (CLEAN algorithm). Our results show that image reconstruction is successful in most of our science cases, yielding images with a 4 milliarcsecond resolution in K band. (abridged)Comment: 11 pages, 36 figure

The mass-loss return from evolved stars to the Large Magellanic Cloud V. The GRAMS carbon-star model grid

The total dust return rate from AGB and RSG star outflows is an important constraint to galactic chemical evolution models. However, this requires detailed radiative transfer (RT) modeling of individual stars, which becomes impractical for large data sets. Another approach is to select the best-fit spectral energy distribution (SED) from a grid of dust shell models, allowing for a faster determination of the luminosities and mass-loss rates for entire samples. We have developed the Grid of RSG and AGB ModelS (GRAMS) to measure the mass-loss return from evolved stars. The models span the range of stellar, dust shell and grain properties relevant to evolved stars. In this paper we present the carbon-star grid and compare our results with data of Large Magellanic Cloud (LMC) carbon stars from the SAGE and SAGE-Spec programs. We generate spherically symmetric dust shell models using the 2Dust code, with hydrostatic models for the central stars. We explore five values of the inner radius R_in of the dust shell (1.5, 3, 4.5, 7 and 12 R_star). We use amorphous carbon dust mixed with 10% silicon carbide by mass. The grain sizes follows a KMH distribution. The models span 26 values of 11.3 um optical depth, ranging from 0.001 to 4. For each model, 2Dust calculates the output SED from 0.2 to 200 um. Over 12,000 models have dust temperatures below 1800 K. The GRAMS synthetic photometry is in good agreement with SAGE photometry for LMC carbon-rich and extreme AGB star candidates, as well as spectroscopically confirmed carbon stars from the SAGE-Spec study. Our models reproduce the IRAC colors of most of the extreme AGB star candidates, consistent with the expectation that a majority of these enshrouded stars have carbon-rich dust. Finally, we fit the SEDs of some well-studied carbon stars and compare the resulting luminosities and mass-loss rates with those from previous studies.Comment: 16 pages, 13 figures, accepted for publication in Astronomy & Astrophysic

Phase Closure Image Reconstruction for Future VLTI Instrumentation

Classically, optical and near-infrared interferometry have relied on closure phase techniques to produce images. Such techniques allow us to achieve modest dynamic ranges. In order to test the feasibility of next generation optical interferometers in the context of the VLTI-spectro-imager (VSI), we have embarked on a study of image reconstruction and analysis. Our main aim was to test the influence of the number of telescopes, observing nights and distribution of the visibility points on the quality of the reconstructed images. Our results show that observations using six Auxiliary Telescopes (ATs) during one complete night yield the best results in general and is critical in most science cases; the number of telescopes is the determining factor in the image reconstruction outcome. In terms of imaging capabilities, an optical, six telescope VLTI-type configuration and ~200 meter baseline will achieve 4 mas spatial resolution, which is comparable to ALMA and almost 50 times better than JWST will achieve at 2.2 microns. Our results show that such an instrument will be capable of imaging, with unprecedented detail, a plethora of sources, ranging from complex stellar surfaces to microlensing events.Comment: 11 pages, 26 figure

EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2016 update

Recent insights in rheumatoid arthritis (RA) necessitated updating the European League Against Rheumatism (EULAR) RA management recommendations. A large international Task Force based decisions on evidence from 3 systematic literature reviews, developing 4 overarching principles and 12 recommendations (vs 3 and 14, respectively, in 2013). The recommendations address conventional synthetic (cs) disease-modifying antirheumatic drugs (DMARDs) (methotrexate (MTX), leflunomide, sulfasalazine); glucocorticoids (GC); biological (b) DMARDs (tumour necrosis factor (TNF)-inhibitors (adalimumab, certolizumab pegol, etanercept, golimumab, infliximab), abatacept, rituximab, tocilizumab, clazakizumab, sarilumab and sirukumab and biosimilar (bs) DMARDs) and targeted synthetic (ts) DMARDs (Janus kinase (Jak) inhibitors tofacitinib, baricitinib). Monotherapy, combination therapy, treatment strategies (treat-to-target) and the targets of sustained clinical remission (as defined by the American College of Rheumatology-(ACR)-EULAR Boolean or index criteria) or low disease activity are discussed. Cost aspects were taken into consideration. As first strategy, the Task Force recommends MTX (rapid escalation to 25 mg/week) plus short-term GC, aiming at >50% improvement within 3 and target attainment within 6 months. If this fails stratification is recommended. Without unfavourable prognostic markers, switching to—or adding—another csDMARDs (plus short-term GC) is suggested. In the presence of unfavourable prognostic markers (autoantibodies, high disease activity, early erosions, failure of 2 csDMARDs), any bDMARD (current practice) or Jak-inhibitor should be added to the csDMARD. If this fails, any other bDMARD or tsDMARD is recommended. If a patient is in sustained remission, bDMARDs can be tapered. For each recommendation, levels of evidence and Task Force agreement are provided, both mostly very high. These recommendations intend informing rheumatologists, patients, national rheumatology societies, hospital officials, social security agencies and regulators about EULAR's most recent consensus on the management of RA, aimed at attaining best outcomes with current therapies

Racial differences in systemic sclerosis disease presentation: a European Scleroderma Trials and Research group study

Objectives. Racial factors play a significant role in SSc. We evaluated differences in SSc presentations between white patients (WP), Asian patients (AP) and black patients (BP) and analysed the effects of geographical locations.Methods. SSc characteristics of patients from the EUSTAR cohort were cross-sectionally compared across racial groups using survival and multiple logistic regression analyses.Results. The study included 9162 WP, 341 AP and 181 BP. AP developed the first non-RP feature faster than WP but slower than BP. AP were less frequently anti-centromere (ACA; odds ratio (OR) = 0.4, P < 0.001) and more frequently anti-topoisomerase-I autoantibodies (ATA) positive (OR = 1.2, P = 0.068), while BP were less likely to be ACA and ATA positive than were WP [OR(ACA) = 0.3, P < 0.001; OR(ATA) = 0.5, P = 0.020]. AP had less often (OR = 0.7, P = 0.06) and BP more often (OR = 2.7, P < 0.001) diffuse skin involvement than had WP.AP and BP were more likely to have pulmonary hypertension [OR(AP) = 2.6, P < 0.001; OR(BP) = 2.7, P = 0.03 vs WP] and a reduced forced vital capacity [OR(AP) = 2.5, P < 0.001; OR(BP) = 2.4, P < 0.004] than were WP. AP more often had an impaired diffusing capacity of the lung than had BP and WP [OR(AP vs BP) = 1.9, P = 0.038; OR(AP vs WP) = 2.4, P < 0.001]. After RP onset, AP and BP had a higher hazard to die than had WP [hazard ratio (HR) (AP) = 1.6, P = 0.011; HR(BP) = 2.1, P < 0.001].Conclusion. Compared with WP, and mostly independent of geographical location, AP have a faster and earlier disease onset with high prevalences of ATA, pulmonary hypertension and forced vital capacity impairment and higher mortality. BP had the fastest disease onset, a high prevalence of diffuse skin involvement and nominally the highest mortality

Digital ulcers predict a worse disease course in patients with systemic sclerosis

none120noneMihai, Carina*; Landewé, Robert; Van Der Heijde, Désirée; Walker, Ulrich A.; Constantin, Paul I.; Gherghe, Ana Maria; Ionescu, Ruxandra; Rednic, Simona; Allanore, Yannick; Avouac, Jéroˆme; Czirják, László; Hachulla, Eric; Riemekasten, Gabriela; Cozzi, Franco; Airò, Paolo; Cutolo, Maurizio; Mueller-Ladner, Ulf; Matucci-Cerinic, Marco; Launay, David; Dobrota, Rucsandra; Sfrent-Cornateanu, Roxana; Zingarelli, Stefania; Pigatto, Erika; Cuomo, Giovanna; Caramaschi, Paola; Ananieva, Lidia; Ullman, Susanne; Iversen, Line; Gurman, Alexandra Balbir; Braun-Moscovici, Yolanda; Carreira, Patricia E.; Joven, Beatriz E.; Minier, Tünde; Guiducci, Serena; Bellando-Randone, Silvia; Pellerito, Raffaele; Hunzelmann, Nicolas; Tarner, Ingo H.; Radominski, Sebastião Cezar; De Souza Müller, Carolina; Iannone, Florenzo; Henes, Jörg; Bancel, Dominique Farge; Damjanov, Nemanja; Ostojic, Predrag; Pozzi, Maria Rosa; Hesselstrand, Roger; Denton, Christopher; Krasowska, Dorota; Tikly, Mohammed; Riccieri, Valeria; Cantatore, Francesco Paolo; Corrado, Ada; Da Silva, José Antonio Pereira; Salvador, Maria João; Tyndall, Alan; Gabrielli, Armando; Distler, Oliver; Jordan, Suzan; Heitmann, Stefan; Burkhardt, Harald; Himsel, Andrea; Rozman, Blaz; Smith, Vanessa; Keyser, Filip De; Kalitena, Dusanka Martinovic; Radic, Mislav; Filipescu, Ileana; Petcu, Ana; Vlachoyiannopoulos, Panayiotis; Kucharz, Eugene J.; Widuchowska, Malgorzata; Kopec-Medrek, Magdalena; Kotulska, Anna; Szücs, Gabriella; Stankovic, Aleksandra; Stamenkovic, Bojana; Selmi, Carlo Francesco; Santis, Maria De; Marasini, Bianca; Coleiro, Bernard; Santamaria, Vera Ortiz; Westhovens, René; Becvár, Radim; Novak, Srdan; Engelhart, Merete; Meroni, Pierluigi; Ingegnoli, Francesca; Zeni, Silvana; Sulli, Alberto; Distler, Jörg; Yavuz, Sule; Montecucco, Carlomaurizio; Eyerich, Kilian; Krummel-Lorenz, Brigitte; Zenone, Thierry; Midtvedt, Øyvind; Chizzolini, Carlo; Seidel, Matthias; Oleszowsky, Mara; Üprus, Maria; Opriş, Daniela; Groseanu, Laura; Bielecka, Otylia Kowal; Antonio, Zea Mendoza; Szechinski, Jacek; Morovic-Vergles, Jadranka; Scorza, Raffaella; Puppo, Francesco; Mathieu, Alessandro; Anic, Branimir; Stork, Jiri; Stebbings, Simon; Inanc, Murat; Hasler, Paul; Von Mühlen, Carlos Alberto; Aringer, Martin; Popa, Sergei; Li, Mengtao; Rosato, EdoardoMihai, Carina; Landewé, Robert; Van Der Heijde, Désirée; Walker, Ulrich A.; Constantin, Paul I.; Gherghe, Ana Maria; Ionescu, Ruxandra; Rednic, Simona; Allanore, Yannick; Avouac, Jéroˆme; Czirják, László; Hachulla, Eric; Riemekasten, Gabriela; Cozzi, Franco; Airò, Paolo; Cutolo, Maurizio; Mueller-Ladner, Ulf; Matucci-Cerinic, Marco; Launay, David; Dobrota, Rucsandra; Sfrent-Cornateanu, Roxana; Zingarelli, Stefania; Pigatto, Erika; Cuomo, Giovanna; Caramaschi, Paola; Ananieva, Lidia; Ullman, Susanne; Iversen, Line; Gurman, Alexandra Balbir; Braun-Moscovici, Yolanda; Carreira, Patricia E.; Joven, Beatriz E.; Minier, Tünde; Guiducci, Serena; Bellando-Randone, Silvia; Pellerito, Raffaele; Hunzelmann, Nicolas; Tarner, Ingo H.; Radominski, Sebastião Cezar; De Souza Müller, Carolina; Iannone, Florenzo; Henes, Jörg; Bancel, Dominique Farge; Damjanov, Nemanja; Ostojic, Predrag; Pozzi, Maria Rosa; Hesselstrand, Roger; Denton, Christopher; Krasowska, Dorota; Tikly, Mohammed; Riccieri, Valeria; Cantatore, Francesco Paolo; Corrado, Ada; Da Silva, José Antonio Pereira; Salvador, Maria João; Tyndall, Alan; Gabrielli, Armando; Distler, Oliver; Jordan, Suzan; Heitmann, Stefan; Burkhardt, Harald; Himsel, Andrea; Rozman, Blaz; Smith, Vanessa; Keyser, Filip De; Kalitena, Dusanka Martinovic; Radic, Mislav; Filipescu, Ileana; Petcu, Ana; Vlachoyiannopoulos, Panayiotis; Kucharz, Eugene J.; Widuchowska, Malgorzata; Kopec-Medrek, Magdalena; Kotulska, Anna; Szücs, Gabriella; Stankovic, Aleksandra; Stamenkovic, Bojana; Selmi, Carlo Francesco; DE SANTIS, MARIA LINA; Marasini, Bianca; Coleiro, Bernard; Santamaria, Vera Ortiz; Westhovens, René; Becvár, Radim; Novak, Srdan; Engelhart, Merete; Meroni, Pierluigi; Ingegnoli, Francesca; Zeni, Silvana; Sulli, Alberto; Distler, Jörg; Yavuz, Sule; Montecucco, Carlomaurizio; Eyerich, Kilian; Krummel-Lorenz, Brigitte; Zenone, Thierry; Midtvedt, Øyvind; Chizzolini, Carlo; Seidel, Matthias; Oleszowsky, Mara; Üprus, Maria; Opriş, Daniela; Groseanu, Laura; Bielecka, Otylia Kowal; Antonio, Zea Mendoza; Szechinski, Jacek; Morovic-Vergles, Jadranka; Scorza, Raffaella; Puppo, Francesco; Mathieu, Alessandro; Anic, Branimir; Stork, Jiri; Stebbings, Simon; Inanc, Murat; Hasler, Paul; Von Mühlen, Carlos Alberto; Aringer, Martin; Popa, Sergei; Li, Mengtao; Rosato, Edoard